Hello everyone, welcome back to another session in dentistry and more. Today's topic is parodontal ligament. Parodontal ligament is one of the four components of parodontium. So parodontium is a structure which supports the tooth. So it includes two hard tissues and two soft tissues. Hard tissues are cementum and alveolar board. Soft tissues are ginjeva and parodontal ligament. Ginjeva we are already covered. So today's session is about parodontal ligament. So let's get into the details of parodontal ligament. So parodontal ligament the name itself gives an idea. Peri means around and don't means tooth. So the structures which is around the tooth. So the ligament which is surrounding the tooth is parodontal ligament. So as I mentioned it is one of the four components of parodontium. So it is defined as the parodontal ligament is a connective tissue that surrounds the root and connects it to the bone. So this orange color is parodontal ligament. So it is a connective tissue that surrounds the root and connects it to bone. So it starts from root to the bone and it communicates with the marrow spaces through vascular channels in the bone. So it is something or it is a connective tissue which surrounds the root and connects it to the bone. It is given by Caranza and it has got many names. The synonyms include parodontal membrane, alveolar dental ligament, desmodont, perisemum, gum forces or dental periosteum. So this is a very important essay in dental histology. So this is very frequently asked essay and there are lots of short notes will be asked from this chapter. So you might get a question like explain about gum forces and write about its principal fibers or draw a neat picture and explain about its structure function. So you might be knowing the complete answer of parodontal ligament but you might not be knowing that gum forces is parodontal ligament. So always make sure that you remember all these names such as parodontal membrane, alveolar dental ligament because it connects alveolar bone and tooth, desmodont, perisemum because it covers the symptom, gum forces and dental periosteum. So these are the synonyms of parodontal ligament. Now let us see the extension of parodontal membrane. So this is the parodontal membrane I have drawn in orange color lines. So it extends from coronal direction it is continuous with lamina property of gingiva. So you will be knowing what is lamina property of gingiva because in the gingiva session we had well covered the connective tissue part of gingiva. So this is the this pink color is the connective tissue part of gingiva. So it is continuous with or it is associated with lamina property of gingiva at the coronal side. So this is the crown part, this is the root part. So we say this is the coronal side, this is the apical side. So on coronal side it is continuous with lamina property and it is demarcated by the alveolar crest fiber. So here it is alveolar crest fiber because this is a bone, this is a tip of the bone on a alveolar crest. So such fibers are demarcating this coronal extension of parodontal ligament and at the root apex it merges with the dental pulp. So at the root apex, see this is the root apex and this pink color is a pulp. So at the root apex it merges with the dental pulp. And it ranges in width from 0.15 to 0.38 mm. So 0.15 to 0.38 mm is the width of parodontal ligament, this is the width 0.15 to 0.38. So next is the shape of parodontal ligament. So it is thinnest around the middle third of the root. So this is a root portion. So this is middle portion, it is thinnest around the middle portion or middle third of the root with an R glass appearance. This is an R glass appearance. It is broadened at the coronal and apical side but it is thinnest at the middle third of root. Okay, so this is a coronal third, this is a middle third, this is apical third. So it is thinnest at the middle third. So it looks like an R glass with widened coronal and apical third. And we have a radio opaque boundaries of parodontal ligament. So when we take an X-ray, so we can see an empty space. So parodontal ligament will be shown in X-ray as radio loosened area, that means it is completely black. So there is no structure within it. So the X-ray will not produce any image. So it will be very black in color which is known as radio loosened. But it has two white borders which is known as radio opaque borders. So what are those white borders? One is a alveolar bone and other one is a cementum. So it is outlined by alveolar bone and cementum. So in radiograph it looks like a radio loosened area with radio opaque boundaries. So it is between cementum, this is cementum and alveolar bone. So these are the mineralized structures. So it will appear as radio opaque or white areas. So it appears as black area between two white lines, that is radio loosened area between radio opaque lines. So the average width changes based on the age around 10 to 15 years, it is around 0.21 mm and 30 to 50, 30 to 50.21 mm in 10 to 15 years and 0.18 mm around 30 to 50 years and it is around 0.15. So as the age increases the width of this perirondal ligament decreases and also it changes according to time of eruption at function or hyperfunction. Time of eruption it is around 0.1 to 0.5, it is very highest at function it is around 0.2 to 0.3, this one 0.15 to 0.3 but hyperfunction it again reduces. Now let us move on to the development of perirondal ligament. How does it develop? So we have seen develops from dental follicles. So hope you remember our bell stage, advanced bell stage of tooth formation. We have what stage, gap stage, bell stage. We have learned dentine and pulp develops from dental papilla and cementum, perirondal ligament, alveolar bone develops from dental follicle or dental sac. So it is developed from dental follicle. So what happens? It begins with root formation and prior to the tooth eruption. So at later bell stage when amylogenesis and dentinogenesis are well advanced the internal and external lamina so we know that the internal and external lamina when the stratum intermedium collapses the outer enamel epithelium and inner enamel epithelium approximates and it becomes two layer cells, two layer epithelium with outer enamel and inner enamel epithelium. So it forms or at the cervical loop of enamel organ it becomes bent and makes this double layered epithelial root sheath and this root sheath which proliferates epically and forms the future root and forms the future root. So this is how it forms outer enamel epithelium, inner enamel epithelium it bent at root portion or the cervical portion and it proliferates epically so you know what is epically towards the root epically and forms the future root. So what happens? There will be hard wicks epithelial root sheath at advance bell stage which covers the root area. So this root sheath is continuous so this root sheath is continuous. So it loses its structural integrity and forms the remnants which is known as epithelial rest of molasses. So epithelial rest of molasses forms. So once epithelial rest of molasses forms what happens there will be connective tissue. So there will be the connective tissue, okay this is all let it be connective tissue of dandelion follicle. So from dandelion follicle the connective tissue cells from dandelion follicle migrate to the newly formed root of dentine. So it will be like this. So the remnants gives the endurance, gives the pathway of proliferation towards the root dentine, okay. Before it was a hard wicks epithelial root sheath. It was a continuous layer after that it loses its structural integrity. So the dandelion follicle which is present outside continuous proliferation happens and it goes between the epithelial rest of molasses and forms a periodontal ligament. So that is how it forms and dandelion follicle cell basically produces fibroblasts, cementoblasts and osteoblasts. This is collagen, this is cementum and this is bone, okay. Collagen is a principal fibre of peritontal ligament. So ultimately dandelion follicle give rise to peritontal ligament, cementum and alveolar bone. So as the root formation continues cells in the peripholecular meson give rise to, there will be active synthesis of collagen fibres and this collagen fibres assemble and it forms as a bundle on the bone and cemental surface, okay. So it becomes bundles. So from the dental follicle there will be active synthesis and this fibres will be formed and it will be attached to cementum and bone. So this is how it happens. This is alveolar bone proper. This is a peritontal ligament space and this is a root cementum. So as the growth happens this is a root cemental area, this is the alveolar bone area, there will be a continuous proliferation, mitosis happens and ultimately it joins and it become peritontal ligament. So we have a mature peritontal ligament, three areas that is bone, bone related region bone related region and the middle region and the cementum related region. The bone related region is basically very rich in cells and the middle zone is fewer cells with thinner collagen fibres and the cemental related region which is dense and ordered collagen fibres are present. So bone related region associated with alveolar bone proper, middle region it is thinner and thick bundles of fibres are seen in cemental region because this is a tooth area, this is a bone area see this is a tooth, this is a bone. So this is the picture I have showing here just opposite here it is a cementum is a alveolar bone but here it is alveolar bone here is a cementum. So this is just expanded picture. If I draw this picture it will be like this. So this is how it forms, this is enlarged version of this area but only thing you need to think opposite this is alveolar bone this is root but here it is a root this is alveolar bone. So that is how it forms you can see the various formation one the toothy reps where this is covered within the ginger bar. So there is little bit of periodontal ligament formation as the toothy reps there will be more and more periodontal ligament formation when it is completely replete the bundles will be formed and principle fibres will be completely around the root. So what are the functional changes happens in periodontal ligament? So the basically periodontal ligament is always subjected to change when there is increased functional limit the width may increase as much 50% of the present width because more function more functional limit more stress it need to bear so it will increase its width up to 50% it can increase and fibre bundles also increase in thickness when there is a increased functional demand. Well when functional demand decreases the narrowing of periodontal ligament and decrease in number and thickness of fibres happens. So it can modify itself based on the functional changes. So that is the beginning part of periodontal ligament I have explained to you about its extension its shape and the in detail about the development. So you need to study properly about the tooth formation that is but stage cap stage and bell stage then only it is easy to understand if you don't know that chapter properly it's very difficult because you need to what is Hadoic epithelial rest of Hadoic epithelial root treat and epithelial rest of molasses and how this collagion fibres starting from dental follicle to the cemento man bone. So it is a very important chapter because this is commonly asked essay question so the short notes might be Hadoic epithelial root treat, epithelial cell rest of molasses so all these might come as short notes. So next thing is the structural elements that is cells and extracellular elements. So this is the introduction part development extension shapes and how the periodontal ligament changed according to the functional demands. Now we move on to the structure the cells and extracellular elements of periodontal ligament. Thank you. So now we have the structure of periodontal ligament. So we have basically two categories one is cells and the next one is extracellular substance. So under cells we have basically five categories. The first category is synthetic cells the cells which produces other cells that is osteoblasts which produces bone fibroblast, cementoblast. The second one is resoptive cell which distract the cell, osteoclast fibroblast and cementoclast which distracts bone fibres and cementum. Third one is progenitor cell then epithelial rest of molasses and differential. So the basic differential muscle macrophages and snuffles. So synthetic cells we have osteoblast fibroblast cementoblast resoptive cell the destructive cells osteoclast fibroclast and cementoclast this is blast means create, blast means distract. Progenitor cell epithelial rest of molasses we have seen when the sheath was disrupted the hard wicks epithelial root sheath once it loses its continuity the remnants will be on the periodontal ligament as epithelial rest of molasses and the common differential and in extracellular substances that means the main bulk of substances we have fibres and ground substances in fibres we have collagen fibres and oxytalin fibres in ground substances we have glycosaminoglycans and glycoproteins. Now we will move on to the our principle or the chief component of cells sector that is synthetic cell that is fibroblast which is the architect which is a builder which is a caretaker of periodontal ligament which is very predominant in the periodontal ligament. So basically it originates from cemental surface and also from alveolar bone surface. Cemental surface it originates from ectomation kind of investing layer of dental papilla and dental follicle from the cemental surface whereas the alveolar bone side it is originated from peri vascular meson kind. So both sides it originates towards the cemental surface it is originates from the ectomation kind we have seen in dental papilla and dental follicle and in alveolar bone side it is originated from peri vascular meson kind. So these cells which is oriented with their long axis parallel to the direction of collagen fibres. So how the collagen fibres are oriented so it just follows the long axis parallel to the collagen fibres and which is aligned along between collagen fibres and appearance governed by the surrounding matrix. So these fibroblast of periodontal ligament generate an organizational pattern as they have the ability to both synthesize and shape the proteins of extracellular matrix. So it has both the properties that is the ability to synthesize and shape the proteins of extracellular matrix. So these proteins also it can shape and it can synthesize, synthesize other elements also. So the certain fibres or the fibrils form bundles to get inserted into tooth and bone which is known as sharp piece fibres. This is very important sharp piece fibres. Commonly asked short note so what is sharp piece fibres? So certain fibres or fibres in fibroblast it gets bundled or it gets forms in a bundle and get inserted into tooth and bone. So once it is embedded in the wall of alveolus or tooth these fibres calcify to certain degree which fibres sharpies fibres calcify to certain degree and are associated with an abundance of collagenous proteins found in the bone. So these proteins are known as osteopontin and bone silo protein. So these are associated with sharpies fibres. So what are the functions of fibroblast? Okay not osteoblast, functions of fibroblast. So the first function is to synthesize collagen. First is a collagen synthesize then synthesize fibres. Organized fibres network can generate force on tooth eruption, produce extracellular matrix of periodontal ligament which has capacity to give rise to cementoblast and osteoblast. So fibroblast can give rise to osteoblast and also cementoblast. It maintains a normal width of periodontal ligament which is synthesized and shaped the proteins of extracellular matrix I mentioned earlier in which collagen fibres form bundles and insert into the bone or tooth as sharpies fibres. So it can shape the extra cellular matrix proteins. So it regulates collagen turnover by phagocytosis, phagocytosing the old collagen fibres. Now we will move on to the second synthetic cell that is osteoblast. These cells covers the periodontal surface of alveolar bone which line the tooth socket and our cuboidal in shape with prominent round nucleus at the base cell end of the cell which has rough endoplasmic reticulum, mitochondria and vesicles which are very active and abundant in osteoblast. Microfilaments are prominent beneath the cell membrane and the cell contacts one another through dysmosomes and tight junction. What about cementoblast? Cementoblast they line the surface of cementum which are cuboidal with large vesicle nucleus with one or more nuclei and all the organelles required for proteins in the cesan secretion are present in cementoblast. There are two types of cells that is cells with cytoplasmic process and cells without cytoplasmic process. So cells actively depositing cellular cementum exhibit the cytoplasmic processes and basophilic cytoplasm but whereas a cellular cementum producing cells with which it doesn't have prominent cytoplasmic processes. So these are the two types of cells which you seen in cementoblast type cells. Now let's see the resopty cell. Those are osteoclast, fibroclast and cementoclast. So next we have resopty cells. Resopty cells are nothing but which distracts the cells which is doing the function just opposite of synthetic cells. They create this resopty cells. They distract the cells. So the most common one is osteoclast which basically they resorb on and tend to be very large and multi-nucleated but can also be small and mononuclear. So these multi-nucleated osteoclast are formed by fusion of precursor cells similar to circulating monocytes. The part of plasma membrane lying adjacent which is being resorbed is raised in characteristic folds. So you can see the folds over here, the folds. So this is known as ruffled or striated border. So the part of plasma membrane lying adjacent to bone that is being resorbed is raised in characteristic folds which is known as ruffled or striated border. So these are found against the bony surface occupying shallow depression which is known as how ships lacunae. So there are many short notes will be coming from this one. The ruffled or striated border how ships lacunae and one more thing we have that is clear zone. So you can see this area which is devoid of all the organelles. So this ruffled border is separated from the rest of plasma membrane by a zone specialized membrane that is closely applied to the bone. So it is separated from the rest of plasma membrane by a zone of specialized membrane which is very closely applied to the bone and the underlying is a cytoplasm. This is a cytoplasm which tend to be devoid of organelles and that is known as clear zone. So you know still class we have learned what is ruffled or striated border that is this particular appearance that plasma which is plasma cells, plasma membrane which is close to the bone and it is being resorbed which gives that because resorption will not happen in a linear fashion it will be folding in a foldable fashion it happens. And this seen in a particular depression that is this osteoclast seen in particular depression known as how ships lacunae and there will be a clear zone which is a cytoplasm which is devoid of organelles. Whereas a cemento-clast, cemento-clast the peculiar thing about cemento-clast there does not remodel. So these cemento-clast are not usually found in the periodontal argument because it does not remodel. So these cells seen when there is pathological conditions or during resorption of deciduous teeth and when regressive forces are applied because we forcefully apply forces that forces are being applied on orthodontic therapy. So in orthodontic therapy we apply forces that is intentional forces and that cases we can see cemento-clast. So these cemento-clast resemble osteoclast and are located in depression and cementum resembling how ships lacunae. So this is not usually seen in periodontal argument it comes when there is a pathological problem resorption of deciduous bone and the orthodontic forces. And one more thing these cells not only just resorpt cementum but also they can destroy dentine and enamel. So this is also known as odendoclast. So odendome means tooth. So clast is something which is destructing structure. So this is also known as odendoclast because it destruct enamel and dentine. Now we have our third category. So we finished fibroclast is nothing but cell switch destruct fibbus or collagen. So osteoblast creates bone, fibroblast creates collagen, cemento-blast creates cementum, osteoclast destruct bone and fibroclast destruct collagen, cemento-clast destruct cementum. Now we are moving on to our third cell which is progenitor cell. So progenitor cell is all connected tissue including PDL which contains progenitor cells that have the capacity to undergo mitotic division. So mitosis is the basis of replication of cells. So these are undifferentiated mesenchymal cells that have a perivascular location within around 5 micrometers of blood vessels. So when stimulated appropriately these cells undergo mitosis and what are the cells will be formed. So we have fibroblast, osteoblast or cemento-blast that in turn produces collagen, bone and cementum. So progenitor cells are the cells which produces osteoblast, fibroblast and cemento-blast. So this should be here progenitor as a primitive cells that itself give rise to osteoblast, fibroblast, cemento-blast. So that is the synthetic cell of synthetic cell we can say. And we have epithelial rest of molasses. We already discussed it. There will be epithelial ruci that is half weeks epithelial ruci which undergo lysis and there will be epithelial rest of molasses because it loses its continuity and the epithelial rest will be seen along the root surface as like strands or islands or tubular structures which will be parallel to the surface of root which has around 25 micrometre in diameter. So their function is not yet clear but they could be involved in periodontal repair and regeneration. So it is most numerous in apical and cervical areas children it is very numerous as we age the number reduces these cells may proliferate to form am tumors. And one more thing we have the cells that the epithelial rest of cells undergo calcification to become cementicals. So what all we learnt? We learnt ruffle or striated border, how ships lack on it, clear zone, odendoclast and cementicals. These all are shock notes. So osteoclast, osteoplast, fibroblast, fibroclast progenitor cell, epithelial rest of molasses hardwicks, epithelial root sheath cementicals all will be asked for shock notes. So this is a very common SA periodontal recommend so we have not done so we are into our cells. Now we go to the defense cells. So defense cells are common defense cells we have mast cell, e-snow fill and macrophages. Now we need to study the extracellular substances. So we had seen the basic structure the basic origin and its shape after that we moved to the structural cell. Structural cell we have structure and we have cells and extracellular proteins. We finished cells now we have extracellular substances. Now let's see the extracellular substances. So extracellular substances we have fibres and ground substances. In fibres we have collagen elastic reticular, secondary fibres, oxitalin fibres and also in different fibres plexus. So the collagen fibres are the main fibres which is the basic types are type 1 and type 3 the 70% age belongs to type 1 and it is uniformly distributed in the ligament whereas type 3 which accounts for around 20% age found in periphery of sharpies fibres and type 4 and type 7 which are associated with epithelial cell rest and blood vessels. So type 13 which is associated with PDL when the ligament is completely functional and the collagen is gathered to form bundles and approximately 5 micrometer diameter and these bundles are termed as principal fibres so principal fibres are very important the next video I will be doing the principal fibres so within each collagen bundle the subunits are present which is known as collagen fibrills so fibrills combine to form fibres now we have the turnover rate of collagen this is faster than all other connective tissue collagen present in the connective tissue because it is highestly seen in pedodontal ligament the turnover of collagen and the rate appears to be highest towards root apex and the collagen on both side has lower turnover rate than that on the bone side where it shows higher turnover rate so towards the bone side it has having higher turnover rate and now we are moving on to ground substances principal fibres will be dealt in next video the major glycosaminoglycans are contributing sulphate, dermatone sulphate, heparin sulphate, hyaluronic acid and keratin sulphate so glycoproteins we have various type fibronectin these glycoproteins are densely packed proteins with extracellular matrix and they have been localized in the calcified sections of human pedodontal ligament the most common is fibronectin it promotes attachment of cells to substratum especially to collagen it is expressed strongly along attachment sites of collagen fibres to cementum but not bone in addition to its function it is also having functions such as blood coagulation wound healing and chemotaxis so it promotes cell addition to collagen it is associated with collagen fibres to cementum next we have tenacin it is also known as cytotactin it is the other glycoprotein identified in the pedodontal ligament it is found mostly in healing wounds unlike fibronectin it is not uniformly distributed throughout the PDL but is concentrated between the less densely packed collagen fibres near cementum and alveolar bone so laminin is a glycoprotein component of basement membrane of epithelial cell rest of molasses which has properties like cell adhesion, migration and differentiation so these are the basic extracellular substances which are glycosaminoglycans we have many types and also the glycoproteins now let's move on to the principle fibres of pedodontal ligament so pedodontal principle fibres so these fibres are collagenous in nature and it follows a wavy pattern so you can see a wavy pattern when viewed in a longitudinal section this is the cross section this is the longitudinal section so you can see a wavy pattern so they are thought to contribute the regulation of mineralization and tissue cohesion at sites of increased biomechanical strain so when there is a strain so in orthodontic movement when there is strain and stress there will be remodelling and changes in the pedodontal ligaments or the fibres so we have basically five groups principle fibres they are alveolar crest group horizontal group, oblique group apical group and interradicular group it's a very important topic in pedodontal ligament it might be asked as a short note or a long essay so let's see the five principle fibres alveolar crest, horizontal group, oblique group apical group and interradicular group so I have drawn all these the green colour is apical the black colour is oblique the pink colour is horizontal the violet is interradicular the orange is alveolar crest so let's see one by one alveolar crest group is extends obliquely from cementum this is a cementum just beneath the junctional epithelium to the alveolar crest and to the fibres layer of periosteum covering the alveolar bone so this is the alveolar bone and it is a crest so it is starting from the cementum that is oblique you can see this is not horizontal this is not perpendicular this is at an angle ok so this is oblique this is horizontal this is oblique so it extends from cementum just beneath the junctional epithelium and to the alveolar crest so this is alveolar crest and to the fibres layer of periosteum covering the alveolar bone the horizontal fibres they extend from cementum to alveolar bone in horizontal direction at right angle to the long axis of tooth so this is a long axis of tooth and horizontal is at right angle which is starting from cementum to the alveolar bone and it occupy 10-15% of coronal root surface now we have oblique group oblique group it is the largest group of fibres and it is around 80-85% of root surface it extends from cementum in a coronal direction oblique to bone so it is extends from cementum going at oblique direction towards the bone ok so this is the alveolar crest group which is running oblique direction this is the oblique group is the largest periodontal ligament fibres and it is running from cementum to alveolar bone it is around 80-85% of total root surface now we have apical group so this is apical group the apical fibres radiate in a rather irregular fashion from cementum from cementum to the apical region of socket and they do not occur in incompletely formed roots these may occur in incompletely formed roots but apical will not occur until and unless the root formation is complete so this is going in irregular fashion from the cementum to the alveolar to the socket ok so this is apical group and the last one is interradicular group so this is interradicular group this violet one they fan out from cementum to the tooth in the forkation areas of multirooted tooth ok so this is like multirooted tooth they fan out from cementum to the forkation areas now let's see what are the functions of these fibres the alveolar crest are involved in retaining the tooth in the socket which opposes lateral forces forces and it prevents extrusion and intrusion extrusion is moving away from the socket and intrusion is moving towards the socket so it prevents extrusion and intrusion of tooth protect deeper periodontal ligament structures the horizontal group is restraining the lateral tooth movement whereas the oblique group which bear the vertical masturbatory stresses and transform them into tension on alveolar bone and resist intrusive forces so intrusive forces is towards apex so it resists vertical masturbatory forces and the next one is apical group so the basic function of apical group fibres are it prevents tooth tipping and it resists lexation it protect blade, lymph and also place to the tooth since it is at the apical position and the inter radical group which helps in resisting tipping, talking and lexation movements of the tooth so these are the principle fibres of periodontal ligament it's a very important topic so alveolar crest horizontal oblique apical and inter radical you need to draw this picture very neatly and explain the origin and its end and the basic functions now we have various other fibres that is sharpies fibres we already seen these sharpies fibres they are collagen bundles of periodontal ligament embedded into cementum and alveolar bone the orientation is similar to that of adjacent periodontal ligament bundles and they are more numerous but smaller at their attachment into cementum than alveolar bone these fibres in cellular cementum will be fully mineralized but in cellular cementum it is partially mineralized and few sharpies fibres pass uninterruptedly through bone of alveolar process which is known as trans alveolar fibres trans alveolar fibres are nothing but sharpies fibres which pass uninterruptedly through bone of alveolar process and the next one is intermediate plexus so intermediate plexus in the beginning it was believed that principle fibres follow a wavey course from cementum to bone and are joined in the mid region of the periodontal space giving rise to a zone of distinct appearance which is known as intermediate plexus which is starting from cementum to bone in a wavey course at the middle region a peculiar appearance periodontal space giving a zone of distinct appearance which is known as intermediate plexus in recent time the concept has little bit changed so the recent concept is that fibres cross the entire width of periodontal space but branches and join neighboring fibres to form a complex three dimensional network so forming a three dimensional network is the reason for that peculiar appearance of that mid region next is elastic fibres elastic fibres there are three types of elastic fibres which are histochemically and ultrastructurally different they are mature elastic fibres eulene fibres and oxytalene fibres eulene fibres and oxytalene fibres have been described as immature elastic fibres so mature elastic fibres they consist of microfibrillar component which is surrounding an amorphous core of elastin protein whereas oxytalene fibres they are microfibres which run in apicocoronal direction to bend and attach to cervical third of fruit and thus the function of oxytalene fibres basically unknown but it has role in supporting blood vessels of periodontal ligament and there is also tooth supporting function eulene fibres are bundles of microfibres embedded in small amount of amorphous elastin their basic functions regulate vascular flow and role in tooth support and facilitate fibroblast attachment and migration the reticular fibres they are immature collagen fibres with staining properties and are related to basement membrane of blood vessels and epithelial cells which is adjacent to periodontal ligament whereas the secondary fibres they represent the newly formed collagenous element but still it is not incorporated into the principal fibres so located between these principal fibres they are basically non directional and randomly oriented they appear to transverse the periodontal ligament space in corona apical and are often associated with the vasculature and nervous elements but so that is all about principal fibres so we have seen the principal fibres and other fibres so next we have the functions of periodontal ligament so principal fibres are very important question it might be asked as short assay or long assay and even a short knot either any group of principal fibres so I will come up with functions of periodontal ligament so now we are into the last segment of our periodontal ligament so this session is about functions of periodontal ligament so there are basically 5 types of functions physical functions, formative and remodelling function nutritional function, homeostatic function and sensory functions in physical functions the first thing is it provides a soft tissue casing to protect the vessels and nerves from injury by mechanical forces so it protects it because it act as a casing and protects the underlying nerves and vessels the second physical function is the occlusal forces to the bone the bone is transmitted the force is happening at the occlusal side and it is transmitted to the bone so when there is a force so when there is a force it will be transmitted to the bone so it will be transmitted to the bone and attachment of teeth to the bone as we had seen and maintenance of the gingival tissue in the proper relationship with the teeth and resistance to the impact of occlusal forces they are the physical functions it provides casing, it transmit forces, it attach the teeth to the bone it maintain the gingival tissues and it resist the impact of occlusal forces so basically there are various theories which explains this the forces how the force is transmitted to the bones through periodontal ligament the first theory is tension theory then the viscoelastic theory and one more theory we have thixotropic theory so what is tension theory? when a force is applied to the crown principal fibres first unfolds and straightens then transmit the force to the alveolar bone which causes elastic deformation of the bone socket then finally the alveolar bone has reached its limit the load is transmitted to the basal bone so this is the alveolar bone then we have a basal bone that is mandible and maxilla so that is the tension theory basically says that the principal fibres of periodontal ligament are the major factors in supporting the tooth and transmitting the forces to the bone so the principal fibres unfolds it transmits to the alveolar bone alveolar bone elastic formation changes happens and it reaches a limit then it transmit to the basal bone but many investigators find this theory insufficient to explain the experimental evidence then came the viscoelastic theory according to this theory what happens when a force is applied on the tooth there is a change in extracellular fluid so extracellular fluid which fluid from periodontal ligament escapes to this marrow spaces because the tooth will be compressed when force is there the tooth will be compressed so fluid will be escaping to the marrow spaces so depletion of fluid so the fibres absorbs and it becomes titan so fluid will be into this marrow spaces the fibres absorb the pressure and it titans blood vessels stenosis so arterial back pressure created ballooning of vessels and then passage of blood ultra-filtrates into the tissues so the lost fluid replenished so this is a viscoelastic theory when force applied the fluid enters into marrow spaces then there will be tightening of this fibres blood vessels stenosis arterial back pressure created ballooning of vessels then passage of blood ultra-filtrates into the tissues so the lost fluid replenished so according to this theory the displacement of tooth is largely controlled by the fluid moments with fibres having only secondary role so the intentional theory was explaining the primary cause is due to the principal fibres so there is a big difference between tangential theory and viscoelastic theory viscoelastic theory is an accepted one and the next theory we have thixotropic theory so it says that the PDL has rheologic behavior of a thixotropic cell and fluoride when it applies pressure it becomes liquid when applied pressure it becomes gel when there is no pressure it is semi-solid again so this is commonly used technique in fluoride application fluoride gel application mostly they are in semi-solid state but when we put it in the trays and apply pressure it becomes liquid or it becomes gel type and it enters into the internal spaces so the presence of organized collagen fibres makes this theory unacceptable so the most accepted one is viscoelastic theory and the second function is formative and remodeling the cells of PDL which participate in formation and resorption of cement and bond which occurs in physiologic tooth movement, accommodation of pyridontium to occlusion forces and also in repair of injuries and remodeling the three-dimensional organization of fibre mesh work is adapted to accommodate for positional change of tooth when there is changes in functional state happens it relates to the adaptability of pyridontal ligament tissues both these process can occur simultaneously and may therefore be indistinguishable the formation and remodeling so this PDL is constantly undergoing remodeling all cells and fibres are broken down and replaced by new bone or new ones and mitotic activity can be observed in fibroblast and other cells third function is nutritional PDL supplies nutrients to cement and bond ginger by the blood vessels which provide all the anabolides and other substances to cement and bond and ginger and which removes catabolides fourth function is homeostatic which is the adaptability to rapidly changing applied forces and its capacity to maintain its width at constant diameter that is a constant diameter throughout the life it is evident that the cells of PDL have the ability to resolve and synthesize extra cellular substances of connected tissue alveolar bone and cement so that is homeostatic property then we have sensory function though the pyridontal ligament is abundantly supplied with sensory neurofibers which is capable of repair of transmitting tactile pressure and pain sensation by the trigeminal pathway so basically four types of neural terminations are seen most efficient in proprioceptive mechanism so four neural terminations are free nerve endings then roughening like mechanoreceptors which is seen in the apical area and miscellaneous copper cells which is seen at the middle and spindle like pressure and vibration endings which is also seen at epics so which are the four one is free nerve endings which is basically elicit pain and roughening mechanoreceptors which is seen at the apical area miscellaneous copper cells mechanoreceptors seen at the middle third and spindle like pressure and vibration endings which is also seen at epics now we need to study the age changes in pyridontal ligament so what are the changes happening over the age so increase in collagen fibrosis and decreasing in cellularity there will be areas of hyalinization the sporadic mineralization of fibres may also occur decrease in the number of pyridontal fibres cellularity and formation of multi-nucleated fibroblasts decrease in collagen synthesis the surface of pyridontal alveolar bones are dragged and uneven and become irregular in nature replacement of some of the PDL space by fat cells so there are many changes happens as age progresses and width of pyridontal ligament space for non-functioning teeth it is narrower than that of functional teeth and with increasing age less teeth are present the force acting on the remaining teeth may increase and an increasing width of the pyridontal ligament space with age seen with those particular teeth so that is all about pyridontal ligament functions we have five functions physical, formative, remodeling nutritional, homeostatic sensory functions and the tension theory viscoelastic theory and tixotropic theory we have seen and the most accepted one is viscoelastic theory that is saying the fluid movements is cause for transmission of force now last but not the least we need to study the blood supply which is basically inferior and superior alveolar arteries which has three sources like apical vessels that is dental artery which supply dental pulp then the trans alveolar vessels trans alveolar vessels which is penetrating vessels from alveolar bone and the third one is intraceptal vessels which is anastomosing vessels from the ginger in nerve supply we have sensory and autonomic nerves that is basically trigeminal nerve the nerve endings we have four types, roughenies endings miscellaneous corpuscles free nerve endings also we have seen an encapsulated spindle type roughenies endings found near the root apex appear as dendritic and in terminal expansion among the PDL fibro bundles they are mechanoreceptors miscellaneous corpuscles seen at mid root for tactile perception encapsulated spindle type which is a temperature receptor associated with root apex the lymphatic drainage which follow the course of blood vessels ok so that's all about periodontal ligament we had covered in four sessions first session was the basic structure its formation second session was its cells extracellular material third session was the principal fibres and the last session was about the function age changes, blood cell linear supply and lymphatic drainage so we finished periodontal ligament it was a lengthy chapter lots of questions will be asked so we have covered dendriva and periodontal ligament those are the soft tissues of periodontium now we will move on to the cementum and alveoli which are the two hard tissue components of periodontium ok so I will come up with cementum in my next session, thank you


A federal high court in Lagos rules that married certificates issued by Iqoyi Registry were worthless. A federal government says otherwise, will seek to find answers. Niger's debt profile rises to 38.005 trillion between July 1st and September 30th, 2021. Just how do we stay afloat? The National University's commission ranks University of Ibarra on as force in its latest 2021 ranking. And we'll be taking a look at the dailies with an analyst to review them. Many thanks for joining us on the breakfast and plus TV Africa. I am Justin Akadone. And I am Massey Bopo. It's good to have you join us this beautiful morning. Alright then, as always, we'll start off with what's trending across our social media spaces and the world of Nigerian and indeed also maybe the world in a re-talking about. And the first one we will focus on this morning is the Omicron variant and of course the red list and fortunately, as it were, Niger and other countries have been removed from that list which was put by the United Kingdom. Osama said it is some chairing news but over time we have had to discuss on the show here and it was out of them all the talks or the conversation or the negotiations and of course an outcry that eventually the UK government took Nigeria off the red list. Massey. Well, it's a very good one that we have been taking off the red list but it doesn't also stop the fact that there are still some issues and some consents that we need to address and if you actually look at it, it feels like the spin of war doesn't feel like the spin of war and I'm thinking that for us to get to that point, you know, we need to begin to put our acts together for political power equals economic power. So if we sought our economy, if we have some economic might and strength and we're able to put our house together and fix ourselves, I'm not sure that, you know, in the future we'll probably have a reputation of all of this. So well, it's a good one. It's a very good one. I mean, a lot of people for once have actually supported this government for that particular action of reciprocating the gesture that was done by the United Kingdom. If you look at it in all ramification, it's not fair, you know, it's so unjust. If you're saying you're putting this country and all of these countries, especially, you know, in Africa, on that red list, you want to begin to also look at the other countries and find out why are we on the red list and why are they not on the red list because they seem to have more cases, you know, than some of the countries in the continent. So scientifically, it is not, you know, correct. And in all fairness, it is not correct. So it's a good one that we have been taking out, but the issues, you know, that probably will lead to all of this needs to be addressed. We need to begin to put our arcs together. We can constantly be very dependent, you know, on the West for everything that we want. And, you know, COVID-19 should be, I'm hoping that it should have been, or should be, an eye-opener for everyone. Well, it is an eye-opener for everyone. And we should, or Africans, that is not the blimp because we were the ones who discovered the variant here. I mean, we just felt as though we're being punished for, you know, trying to save the world as it were. In South Africa, they were really forthcoming. They were not in denial. When they found that particular or discovered the Omicron variant, they announced it to the world. I didn't even say any reason why we should be, you know, punished as it were. But some other issues actually came out of all of this. And, you know, there was this issue between an airpiece and, of course, and, you know, Emirate airline, there's this bilateral service agreement popularly called AMBASA. Before now, it was a Nigerian gave the UAE, the United Emirates, rather, about 21 spots, and we heard that we did not even get commensurate, you know, slots, you know, to fly within that particular space. But from what we understand right now, our slots to airpiece has actually increased to about seven. And the issue of diplomacy, you know, came to the front burner in all of this. You know, yesterday, you know, it was almost like a heated argument between both some guests that we had that, you know, one of them was saying that we should avoid using some words. We, which connotes that countries are actually at war when they talk about diplomacy. So we should not retaliate, you know, in other words. But the good thing is that right now, we are particularly off that list and, you know, Nigerians can, you know, actually fly, you know, into the United Kingdom. Another story trending right now is that then Nations and Premier University, that's at the University of Ibadan. And from the latest ranking released by the Nigerian University Commission, the University of Ibadan, you know, came talks out of all the universities in Nigeria. Mercy, did you graduate from UI? No, I did not. But, you know, UI is a very permanent university. And from 2016, UI has actually been, you know, topping 100, you know, in the world, if I'm not mistaken. Now, under a lot of factors, there are a lot of things that are actually working out for them. For the fact that, yes, they are actually, you know, if you look at the time that we're actually established, we're looking at 1932, or regionally established. And of course, they gained full independence in 1962. That's also one thing that is working for them. Another factor also, because, you know, with all of this ranking, there would be some criteria that would be used. But, you know, generally speaking, I feel that the UI is such a great university with 13 faculties, best in medicine, best in economies. And you want to go on, the least is endless. So I think they do deserve it. And I'm hoping that all other universities in Nigeria, you know, would actually look at what UI is doing and see how they can replicate. Well, it is a good thing that the University of Ibadan has actually ranked them first out of all the universities in Nigeria. But then again, we should move away from just, you know, being the first in Nigeria, you know, because the last time I saw such rankings across the world, Nigeria was nowhere to be found amongst the top 100. It is really not something that we should be, you know, talking about, because if we're not in the first one... I think it was 1,000. You know, from 2016, UI would always represent Nigeria in the 1,000. So what we need to... I'm just being first, 1,100. 1,000 is way far and massive. All universities were 1,000. But the fact that we even made it to 1,000 is something to appreciate. We can do better. So basically, to the point that we need to, you know, step up educational standards and for structural development in our investor systems so that Nigerians can actually, you know, reach ahead in pride and say that whatever I can get from the University of California, you know, can be gotten here in Nigeria. So we don't really need to, you know, all travel out to get the better education as we try. Because before now, back in the day, we used to have exchange students come to Nigeria, you know, to learn from our universities. And we also do some sort of exchange programs with other investors. But lately, I mean... I don't even want to talk about... I don't want to talk about, you know, the curriculum. I don't want to talk about the curriculum. I would like to stay with the learning environment because the environment on its own has a lot to impact. The environment on its own would tell. I mean, that's why you would hear a lot of people say, traveling is such an adventure. When you travel, it's important that you take out time to travel, you know, within the country, outside of the country because by traveling, you are educated. So, first of all, let's look at our learning environment. I'm hoping that we can do better. I really do not know, but the couple of universities that I've actually visited, it is really horrible. I mean, talking about the infrastructure, you look at the classrooms or the lecture rooms, as you want to put it, some of them do not... Some people, you would be shocked that a lot of people still sit, students still sit on the floor, these days, you know, to take lectures when we're in the 21st century. I don't want to go, you know, through the entire... I mean, the nine years of how the infrastructure of our, you know, higher institutions are in, you know, the part of the country. I mean, in some part of the country, if not all. Really, really bad. And sometimes you hear, we have labs. How many of these labs are functional? The chemical... I don't want to say it, but probably saying this might just, you know, put everyone. I remember a time where I had to be told to imagine that there was a computer.  Imagine that there was a monitor. Now, the good thing, I was privileged... I used to work privileged. I was privileged to have seen, you know, a computer, a laptop, or see a monitor prior to this time. So imagine someone who was not seen or doesn't have access to a laptop or computer, and then you tell them to imagine. How do you imagine what you don't even know? You have to have a very vivid imagination to be able to achieve that.  I don't know how it is right now. Back in the day when I left, when I left school, we did a course in management information system, MIS.  This was like in 2000, 2001, you know. So we did a course in management information system. So we're being told about the computer parts and everything. The only thing I got to see mercy was a diskette.  It was that bad, you know. I want to believe that things have changed, though, but I'm not going to change. Oh, my darling, I would be sorry to say that things would not change. Maybe it will not change. I want to believe that each student should have a computer. If you're studying computer science without a computer or a laptop, I don't know what you do. I'm just saying that if you look at what we're just talking about basic infrastructure now and the learning environment, you go to some of these universities. They don't even have power supply. I mean, the lecturers are just, you know, somewhere and they have a lot of work to do. But you don't have power supply. They don't have power supply. They're just there and you're expecting them to assess students in that condition. They could be very aggressive. Everywhere is very hot. The whole learning place, you go to the lecture rooms. There are really nothing to write to them about.  And I'm like, what are you doing in school? He said, everywhere is lit because there's light. There's power. That would be the word. Everywhere is lit. So how many of the universities can we say that, you know, the learning environment is very conducive and we can compete with our contemporaries not outside of the world entirely but within, you know, West African region. Let's even say for Ghana. Let's even talk about access to internet. Let's even talk about a lot of issues and not to even talk about the curriculum. So there's a lot to go. But if you also look at it, you will look at our budget. It just shows you that we don't even pay attention. It is not even necessary for us. And because wherever you put your money, wherever your hat is, your money would definitely go. So money's not going there. It just shows that our hat is not even there. I want to give almost a big congratulations to the University of Ibar for actually achieving that particular fit. Being the first ranked among some other investors in Nigeria. This is a call to the entire Nigeria University assistant to opt your game. So aside from getting UI top, other investors too would be upgraded. And of course our children and our students would have a very conducive atmosphere to learn and they can actually compete favorably amongst their peers across the world. It is the breakfast on the plus TV Africa. We'll take a quick break and I call it kola wali or tsundi kola wali be joining us without the press, off the press in a moment, be joining us again.


Hi again, in this lesson we're going to talk about async function in Python programming language. Let's say that we want to define async function, let's call it async function Hi with argument for example name and let's say that our async function returns hello or hi, better say hi plus that name. And let's define similar normal function in Python programming language, let's call it hi and let's put exact the same argument name and let's say return hi plus name. Let's say that we want to run our function to call it, let's call our normal Python function hi and let's put as an argument name John and we will get result hi John. But what will happen if we try to call our async function and provide to it same argument? We will get some answer as coroutine object, a hi and some part of memory, it doesn't matter. The thing that is very interesting in this case is that async function is not as normal function. You can call it as a normal function but you must provide some other function to call your async function, that async function needs to be driven by some other function. So let's define another function that will drive our async function, I'll call it with funny name drive async hi and I will provide coroutine as an argument, our coroutine will be our a hi function. First we need to send with our coroutine something, but I don't want to send anything special so my coroutine will send none. And we want to catch our exception, stop iteration as e and we will return e.value. So we have our function with which our a hi async function will be driven. So if we want to call our async function we will say drive that is funny name just for better understanding how things works, we will call our function and as coroutine we will put our async function a hi and we'll provide as an argument john. Okay we will get an error but if we try to call it again we will get an answer. The reason for this warning is because at first coroutine a hi was never awaited, that's because we called our function here and we get something which is not expected at starting point but every time if you want to call any time your function you can call it with no problem. That's all in this lesson, thanks for watching, happy coding.


This is another concept which has made it around in the world that something else should motivate you to do what you're doing. If what you're doing is significant enough, you don't need any other thing to motivate you. What you're doing is truly significant to life. Why do you need another motivation to make that happen? If you really understand and experience that what you're doing is truly important for every life around you, you don't need a motivation, life just goes on. See, does your heartbeat need a motivation to keep it going? I'm asking you. All the life processes is not asking for any motivation, isn't it? Monsoon's coming, any motivation? No, it's coming year after year because the natural process is going on. Simply like that, in you and me, life is on. What I'm telling you is, if you're doing something which is aligned with the fundamental life process of who you are, this can find a million expressions, it need not be just spiritual teaching. It can find a million expressions that what you're doing is aligned with your fundamental life process, then you will not need anything to motivate you. Simply as a part of life, it will just happen. How much you do simply depends on how much time you invested on upgrading yourself. The problem with the world right now is, people are always trying to upgrade their activity. If you upgrade your activity without upgrading yourself, you are bound to break up somewhere.  Suppose you hit the right kind of speed, all the four wheels will go in four different directions. It won't hold up. If you want to be in that kind of speed and that kind of track, you must repair the machine. Upgradation of this one is important. If you upgrade yourself, activity will simply happen. Many people around me, you know many times think I'm superhuman because of that activity that I perform, this is not about being superhuman. If you explore the possibilities of being human, if you explore the possibilities of the immensity of being human, you will realize you don't have to be a superhuman. Being human itself is super. So you will not need any external drive or some other inspiration. The very process of life will do it.


Hey guys, welcome back to our channel. My name is Andrea with food inventory adventures in food And I am here today with the recipe for chicken stew Now I first discovered this recipe when I lived in South Carolina chicken stew is a milk-based stew with chicken onions and Canned milk and butter and it is absolutely delicious.  I've got my celery and parsley If you decide not to make your own stock then you're going to want to boil your chicken in about six cups of chicken broth And I am using about three and a half Pounds of chicken pieces. I have a preference for dark meat. So that's what I'm using You can use chicken breast if you want or a whole chicken But I would definitely recommend that you use bone-in chicken in order to get that flavor So I'm going to cover this and let it cook and then I will come back and show you next steps So I let my chicken cook and then I shredded it and that's the important step about Chicken stew is that you really want to shred your meat. You don't want it to be in chunks So I shredded it and then I strained the chicken stock. So now I'm going to add the chicken stock back in and if you were making just the traditional I'm just turning up my heat a little bit to a medium if you were making a Traditional chicken stew at this point you would add a large or medium onion You would dice it up very finely. You would add it in here and then you would add your canned milk Chicken stew is kind of like chicken and dressing or turkey and dressing Everyone does it a little bit differently. So the way that my former co-worker used to do it was just with the chicken broth The onion and then she would add in some canned milk and some Cajun seasoning like I said Mine has a little bit of a twist. So I am butter. I forgot you had a stick of butter So I've got my chicken broth in here or stock in here. I've got my chicken I'm gonna add my canned milk. Oh that's in there and I'm going to add a can of drained regular corn Going to add in my potatoes and I'm using two potatoes. You can use less or like I said none Just whatever your preference is and then you're going to add in your stick of butter And you're just gonna let this simmer until the potatoes are done. So about 30 or 40 minutes So I will come back and show you what it looks like So here is the chicken stew I let it cook for about 45 minutes or just until your potatoes are forked tender So here it is and this is not a thick stew So don't expect it to be a thick stew because it's not but it is very very rich You know, it has that one full stick of butter and you don't want to use margarine in this You do want to use the butter. You can see the butter floating in there so it does have all the butter in there and it has the Canned milk and I forgot to show you that I did add some Cajun seasoning to it My co-worker used to add Cajun seasoning to hers And this is a brand that we like slap your mama people traditionally traditionally eat this with crackers And then they sprinkle hot sauce in it So anyway, I hope you guys enjoyed this video If you did please make sure to give us a thumbs up and if you have not subscribed to our channel I certainly hope you'll do so. Thanks so much for watching and we'll see you guys next time


Okay, so let's get started. As a reminder, use the sketched app, rate the talks to select which of the speakers will be the winner for the Oculus or the Nintendo Switch sponsored by IBM. And also, that will give you an entry that you'll be able to write your name. I'm going to raffle for one of the two. We haven't decided which one is for the speaker and participants. So, wait for the noise. So, let's get started with the first talk is the KNCLI. I'm excited to see this one. I'm a fan of the KNCLI, the one-stop shop by David and David. Thank you guys. Hello, everyone. Welcome to the presentation, KN, the one-stop shop for Knative. I'm Naveed, software engineer at VMware, and I've been working on KNCLI. So, I have here with me David. Yeah, hello. So, I am actually David, one of the working group leads in Knative Client, working with Redhead currently and just a background story we used to work with Naveed. I have joined the serverless team in Redhead and unfortunately he left to VMware, but we were colleagues and we are still like good friends. So, back to the presentation then. So, my first slide is trying to answer the common question that could be asked is KN yet another CLI tool and what is the value proposition to use KN instead of Cube CTL and plain YAMLs. So, I think that team was ongoing pretty much with other representations from functions guys and like the developer-oriented talks that maybe not everybody is fan of YAML and YAMLs at all and all the declarative stuff and for that KN is trying to be a bit different with imperative style of commands and with the proposition that we really know what KNative is about and we know the resources, we are typed for it and we would like to help the either beginners but also like veterans that are trying to do a lot of stuff with KNAT resources, deploying services, traffic management, then going to integrations with eventing sources, triggers, brokers, like to cover everything from the first like first class citizen support for KNative. All right, so why KN is one-stop shop? So, we'll see like how to get started with KN and KNative in like a few minutes. So, this is how you install KN. We have it with distorts on brew package managers. You just do brew install KN and it gets you KN installed. As you do KN version, you can see that you'll see what all KNative serving and eventing version it supports. Note that this is showing the versions of serving and eventing that we support, not the ones that you have installed. All right, and let's take a quick look at how you can get started with KNative setup. If you are new to KNative, you have a working docker set up on your local machine. So, we have, you know, I'm going to give a sneak peek into the quick start plug-in that Carlos and Paula has been working. So, this can get you started with KNative in five minutes. So, you install the plug-in quick start and you just do KN quick start kind. You can also do mini cube. So, this is how, you know, it takes. So, just take a look at the last, second last line.  This is just a quick installation of like, how does the serving and eventing installation looks like? So, we are passed through the installation and let's take a look at, you know, how, you know, KN interacts with KNative. So, it just works everywhere. So, KN strictly works with the API contract of KNative. So, whether you have Kubernetes cluster on any of the Kubernetes provider, you just install KNative APIs, serving and eventing APIs on top and you're ready to go. Apart from that, as David mentioned, like we have rich ecosystem of plug-ins. So, we do have special use case plug-ins which can work with directly with KNative APIs or it can work with the Kubernetes cluster that you have. So, any specific requirements on the Kubernetes distribution that can be expanded to KN via the plug-ins. But KN, if you bring up a, can you do installation on OpenShift or on Tanzu or on EKS, KN can just strictly work. All right. So, going directly into serving support, I will just quickly recap and remind that serving is serving the application workloads for the serverless applications actually and with the scale to zero capability. I don't, well, I don't want to reiterate any that was already said about the serving. So, I will just keep it KN-centric from now on. So, we do offer the standard like CRUD operations for all the serving resources with like an extensive service configuration support and I have a slide prepared with all the flags that we have for the services. There is a couple dozens of them and it might be pretty hard to keep with all the annotation formats or anything you would like to do with your services with regard to configurations and all the options you would like to set up. So, we are trying to offer the convenient way for the developers to power through the help messages and quickly find the correct flag without the additional knowledge of the full formats and so on. So, with the traffic management support, we are also trying to ease up the burden with deployments of new revisions and splitting the traffic into multiple revisions with percentages going to each one of those and so on. That will be hopefully better shown in a demo later. And one of the like things that we really, that are really keen on for the KN is like wait for ready support. So, that's built into our every, like every KN service create command would by default wait for the service to be ready, which seems to be very handy when you are trying to develop a new and create and deploy a new KNATU service and just get that instant feedback if it is working or not, if it will eventually get ready and be prepared for you or there is a problem like an image pool maybe or whatever might be. So, with other features, there is an apply command very much the same as the Cube CTL with that regard that it is able to actually merge our KNATU custom resources. So, it is something extra that it's pretty hard to do with just plain as Cube CTL. And finally, we are not like ditching all the YAML support and there is a way to actually generate a lot of or actually generate those outputs that we would normally do on the back end in a github mode. So, you could store that get the YAMLs, edit them by yourself or just see the plainly see the outputs and use them in a version mode that you would just keep it in your github repository and work from there. So, this slide should illustrate our offering for the serving part of KNATU. As you can see, we have that format of noun as a name for the resource and then a verb to manipulate it. And I will show you a few examples of very basic service create command as first. It's as easy as calling a name of the service and the source of the image you would like to create. This one is update of the service with a new target environment variable and traffic splitting to 50%. So, the previous one would get 50% and the new one created would get another 50%. And as I have mentioned, there is an extensive list of all the flags that almost didn't make it to the slides. And finally, I haven't mentioned that in the first serving slide. We have also support for something like adding a multi-container service. So, you are essentially just building it through normal UNIX pipes. So, container add will actually generate that chunks of YAMLs and will feed it to containers through the pipe. And that can be pretty handy if you are working with a lot of containers that we would like to specify for the one service. Thanks, David. So, now we're going to see KeyN supports all the native resources of eventing that has like sources, broker, subscriptions and channels, the complete credit operations for all these resources. It also supports all the sources that KeyNative provides, the EPS of a source, container source and ping source. And with the extensible mechanism of plugins, we are also able to do the credit operations on the extended sources, for example, Apache Kafka and Kamblitz. So, we'll see like how you can expand KeyNative with plugins to also support these extended sources in the ecosystem. Here we see the KeyN support for all the eventing resources that KeyNative eventing provides. So, as you can see, for channels and subscriptions, we have complete credit operation support, beside on sources, like we have list and list types, commands which will list you all the types of sources available in your cluster so that you can do the credit operations on them. And then since we have like one more layer of self commands for source, so you can work with specific sources in your cluster, like EPS source and binding. And for all of them, we support the credit operations. Here is a quick example to give you a sneak peek, like how you can achieve the diagram that's presented above YK and KMN without writing a single YML file. So, as you can see here, we are trying to build a couple of sources that's sending events to a broker. And then we have a couple of triggers, which will be triggered based on a particular filter that we can embed in the cloud events itself. And then we have a couple of interested things that want to subscribe, you know, that we want to land events to. So, as you can see, we'll start from the left, we'll create a couple of things there. So, the green boxes maps to the green commands. So, you create a couple of services, S1 and S2. And then the broker create is simply KeyN broker create. It will use whatever you have configured by default in your cluster, if it's empty channel or some other broker implementation. Then we create a couple of triggers here, where we say that when a filter on cloud events that are of type, say ping is equal to 2. So, this is the filter that we are using that will identify the cloud events that we are interested in. And finally, we are seeing here the sync. With the sync flag, you say, like, what would be the destination of these cloud events? And with broker, we are mentioning that we want to receive the event from this broker. Finally, we are sending events here with the ping source default source. And we want to specify, we want to send the destination of these events to the broker. And here this C override stands for cloud event override. So, with the default parameters that land in them, you know, that has in the cloud event, we are saying that also add ping is equal to one additional key value in the cloud event, so that, you know, trigger can filter on it. And we are saying this is the additional data that we want to send to it. I think that's all. Once this is in place, you know, your events triggered from the sources are then received in sync. So, if you want to implement all of that using YAML, so you'll have a bunch of YAMLs that you need to create in order, but KN gives you this easy to use CLI options. We'll see the demo of this later. Let's move to plugins. So, KN provides kubectl like plugin architecture. You just need to have your plugins with a prefix KN plugin so that KN can understand it. And you can put it in your path or a directory that you can specify in your config directory. So, with that, you know, KN plugin prefix all the binaries. KN provides a command structure for how your plugin would be invoked. For example, if you are doing a Kafka source plugin, so you would say KN plugin source Kafka. So, you will have KN source Kafka command available. We also have inlining mechanism. So, if there is a vendor who has a plugin specific to their Kubernetes distribution, they can inline the plugin right in KN and produce a binary. We'll see how that's done. Decide like we have a bunch of plugins in place. The quick start plugin that we saw earlier is also one of the plugins that's around. As you can see here, we have an admin plugin that gives you all the utilities to work with Kubernetes cluster, a diagram plugin, a function plugin that we just saw the presentation earlier. And as you can see, the last two ones are the extended additional ecosystem sources of eventing like Kafka and Kamblet. So, you would be able to invoke the plugin like KN source Kafka and all the commands beneath it. All right. So, how do you do the plugin inlining? So, on the plugin source, you mentioned that, you know, these are the metadata of the plugins. And on the KN side, you need to specify, you need to wire this plugin in your KN source. And after once that's done, you just do go mod window. So, it pulls in your plugin source code and builds it together.  All right. Over to David. Okay. So, we are closing to the demo side. Here is the like the overview of what we will see on a pre-recorded video. It's a very basic like a processing service broker and even display service just to display the services eventually. What we are going to do is create every resource with KN commands, create triggers to define the relationships, to define filters. And finally, we will try to, there are two implementations and we do have like environment variable feature switch to switch to fast processing for the new implementation. And we will redirect like 50% of it to our service. And if we are finally happy with what we see and what we have tested from that like AB testing, first, we can redirect the whole traffic to the latest revision and how that should work in practice. Okay. I will increase the quality. Hopefully, that will look a bit better. Okay. So, we are calling in a, I'm sorry, I can pause now. Okay. So, we are currently in the KN service create first. As you can see, there is a bit more output than just that service was created because it is running in a synchronous mode. So, we are waiting until the service actually reports that it is ready. And afterwards, we just describe the service to get maybe a bit more details like what's the URL, what image it is running and like the, you can see also the revision split and some of the statuses as well. So, we do the same for the event display service. I won't pause for that. I will just keep it going. So, describe the event display as well. Afterwards, we are creating the broker here. That's not synchronous. So, it is not telling us too much. Just describe command can tell us that it is ready. On the right-hand side, I am setting up the logging monitoring with service log plugin. So, also through everything is done through KN commands. So, as you can see, we are watching the process service log up here. And on the bottom left, bottom right, we are having the event display. So, right now, we are creating the triggers. One will trigger, one will filter messages going from broker to processing service. And the processing service is actually set up to reply back to the broker with different type of cloud event that we will filter then through the event display. Right now, I am going to invoke the event plugin that is very handy to actually test your setup or just to produce events into brokers or into other kinds of things that are addressable. And you can, there is the event plugin is one of the plugins that are released with KN altogether and consumed through homebrew tabs. And there is a build command to build up your cloud events if you would like to have a bit more fields. Right now, I am just specifying the type here. And like one of the fields is KN8Ucon. And hopefully, we will see that processed on the right side. And it took about five seconds. And finally, we see that the message was received on the event display side. So, then we are going to the traffic split. So, there was a traffic split or the traffic flag refactoring recently that allows us to actually mesh everything together in a way that we are updating the service with a new environment variable that will create a new revision. But we are also specifying that for that new revision that will be created, it should receive the 50% of traffic. So, in one command, you are getting like both operations all together. So, through describe, we should see that we have now 50-50 split for the two replicas. And finally, the script is going to create 10 events or send 10 events into our processing service. And you can see that the starting is the name of revision and which revision is like processing the received event. So, there is some split. And the second revision is actually pretty fast compared to the first one and doing more work on it. Yeah. So, that's wrap of our demo. And I think we can go directly to questions or, oh, okay. Sorry. So, the roadmap. What we are actually looking for to do in the client realm. There is a feature track for the context sharing for plugins that would be especially helpful for something like functions. Because functions can be run as a standalone binary but also as a K-native plugin. And the idea is that functions and KN would be aware of each other to share the common things like service name and so on. So, you could operate if you are in a functions context, operate on that, pre-creating functions for your function and so on. Other than that, we have the broker spec management that is going to be implemented that we need to actually really think about how to approach because every broker might have a different solution for the configuration, either from config map to custom resource. So, we need some good UX, how to actually approach it. And from other things, the plugin discovery and management is another big thing. And I think Max is working on the plugin to actually better search for plugins. So, that would be nice to have. And liveness and readiness probe, we don't have that support for serving and we are looking for it. Okay. And now we can continue the questions. That's interesting. We have questions. We have one question. Thank you gentlemen for the presentation. So, last year I had to develop two plugins for KN and maybe some feedback for you or things have changed and improved since then. So, what I was struggling with is standard patterns like listing, JSON formatted output. So, basically I was going back to the KN code base and copied over a lot of libraries and some internal code path to follow the same like KN broker list, KN broker describe. I think there's a lot of pattern that these plugins should be reusing. Can you hear me? Okay. Because you were. And just to make it easier to use for these plugin developers and have documentation or shared libraries like the KN package, KNative package, right? If you build on these sources, I just go to the package and I use the signals package to follow the conventions there. And it would be great to have that for some of the plugins either on a documentation or shareable like libraries code. Same for authentication, plugins need to do authentication and I had to reinvent a lot of stuff. Yeah. So, we do have, we do, we did set up a client PKG on the main KNative organization, but we haven't been doing a great job moving a lot of shared code there. So, like our approach would be that anything that would be valuable sharing with plugins would be consumed from client PKG and client would then depend on client PKG as well for all those common toolings or common utilities that could be shared. So, yeah, it's on the road map for it. And also like contributions are always welcome. We do struggle a little bit with with actually the main power to do that. So, yeah. But it, we are thinking about it and it is on the road map. Thanks for the feedback, Meg. Okay. Good. Thank you. Thank you. Thank you.