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A key factor for the success or failure of a dental implant is the manner in which stresses are transferred to the surrounding bone. This depends on the type of loading, bone–implant interface, the shape and characteristics of the implant surface and the quality and quantity of the surrounding bone. This study was done to evaluate the pattern of stress distribution with two different implant designs in four different densities of bone using 3D finite element analysis. Graphic pre-processing software Ansys version 10 was used for creating the geometric configuration of a section of the mandible with a missing first molar. Eight 3D models of this section restored with implant-supported all ceramic crowns were created. Four of these models were created to simulate a single threaded implant placed in four different densities of bone (D1, D2, D3 and D4). The other four models were created to simulate a single cylindrical implant placed in four different densities of bone (D1, D2, D3, and D4). The Poisson’s ratio (μ) and Young’s modulus (E) of elasticity of the material were incorporated into the model. An average vertical load of 400 N was applied on the occlusal surface of the first molar between the buccal cusp, central fossa and the marginal ridge. Maximum Von Mises stresses in all the eight models were observed at the crestal region or neck of the implant. The stresses observed were more for the threaded implants in all the four densities of bone when compared to that of the cylindrical implants. The study concluded that the cylindrical implant design was more favorable in softer bone than the threaded implant design.

Aims and objectives To evaluate and compare the effect of fiber reinforcement on the dimensional changes of heat-cured poly (methyl methacrylate) resin after processing and immersion in water. Materials and methods Three different heat-cure resins were selected for the present study: (1) Nonreinforced heat-cure methyl methacrylate resin, (2) High Impact heat-cured methyl methacrylate resin and (3) Fiberglass reinforced methyl methacrylate resin. Ninety samples were prepared using three different resins and denture bases obtained for the same. The amount of space between the tissue surface and the cast in the anterior, middle and posterior regions is measured after processing and immersion in water for 17 days using a traveling microscope having a least count of 0.001 cm. Results Mean and standard deviation were calculated for the dimensional changes and were subjected to statistical analysis (Student t-test, unpaired). Among the three groups of resins, fiber reinforced heat-cured methyl methacrylate resin was found to be statistically highly significant in terms of dimensional changes when compared with the nonreinforced and high impact heat-cured resins. Conclusion Dimensional changes were evident in all the planes in the three groups studied and were in the following decreasing order—fiberglass reinforced heat-cured poly (methyl methacrylate) resin, high impact heat-cured poly (methyl methacrylate) resin and nonreinforced heat-cured poly (methyl methacrylate) resin. Clinical significance The fibers are added in order to increase the strength of acrylic resin. Considering only the strength may in turn affect the dimensional accuracy of the acrylic resin resulting in loss of retention and stability, affecting the fit of the denture. How to cite this article Ranganath LM, Shet RGK, AG Rajesh, Abraham S. The Effect of Fiber Reinforcement on the Dimensional Changes of Poly Methyl Methacrylate Resin after Processing and after Immersion in Water: An in vitro Study. J Contemp Dent Pract 2011;12(4):305-317.

Background: Patients with Human Immunodeficiency Virus (HIV) infection are predisposed to numerous opportunistic infections due to decreased cell mediated immunity, Tuberculosis being most common. Low CD4 count is associated with low immunity and higher risk of tuberculosis.Methods: Author conducted a retrospective study in the department of Pulmonary medicine in a tertiary care teaching hospital during January to December 2017. Author collected data of all the patients with HIV diagnosed with Tuberculosis from the ART centre. Author collected demographic details including age, sex, symptoms at presentation, details of diagnosis of TB including type of tuberculosis, CBNAAT results, CD4 count at the diagnosis of TB, details of ART therapy and ATT therapy and outcomes of treatment.Results: Eighty one patients with HIV-TB co- infection were included in the study. Males (70.37%) were more affected than females. Mean age of the study group was 39.97±10 years. Sixty one patients (75.4%) were diagnosed with Pulmonary Tuberculosis and 20 (24.6%) patients were diagnosed with extra pulmonary TB. Mean CD4 counts of the cohort was 226±110/µl. Eighty percent of patients developed Tuberculosis with CD4 count

Meiotic products in higher plants should undergo a determined number of mitotic cycles before differentiating gametes. This creates a unique meiosis-mitosis interface, traverse of which is an absolute requirement for gametophyte development. In the absence of cytokinesis during megasporogenesis - as seen in the bisporic and tetrasporic types - the haploid nuclei produced by meiosis are driven to undergo mitotic cycles within the same cell. Similarly, the last of the mitotic cycles leads to a unique type of cell wall formation resulting in cellularization of the coenocytic female gametophyte, creating a mitosis-cellularization interface. Cell cycle regulation in terms of the molecules that interface with these two key spatio-temporal developmental settings should be of interest to both cell and developmental biologists. High throughput techniques of functional genomics are required for both interpretation of female gametophyte evolution and success of the biotechnological initiatives of transferring apomixis-related genes to crop plants.

Electronmicroscopic study has revealed a dicentric chromosome in the root tip cells of diploid Aloe vera, hitherto unreported in somatic cells of plants. The morphological aspects are described and the implications of such structural features of the dicentric are addressed in a functional perspective. It is also proposed that the presence of two functional kinetochores need not invariably lead to chromosome instability and loss.

The underlying mechanisms responsible for elimination of three of the four meiotic products during microsporogenesis in sedges have remained obscure. Although programmed cell death (PCD) is known to be an integral part of plant development, several aspects, such as the enormous size difference between functional and eliminated cells, nuclear viability of the smaller cells targetted for elimination and the possible dangers of employing PCD-like mechanisms during gametophyte development point to a novel way of selective cell elimination associated with asymmetric division. This paper throws some light on the possible roles of cell plate dynamics and cell fate determinants in pseudomonad development. The rarity and significance of asymmetric division with morphogenetic consequences associated with meiosis are discussed in the context of generally prevalent, mitosis- associated asymmetric divisions during development.

The widespread use of block-based interframe motion estimation for video sequence compression in both MPEG and H.263 standards is due to its effectiveness and simplicity of implementation. Nevertheless, the high computational complexity of the full-search algorithm has motivated a host of suboptimal but faster search strategies. A popular example is the three-step search (TSS) algorithm. However, its uniformly spaced search pattern is not well matched to most real-world video sequences in which the motion vector distribution is nonuniformly biased toward the zero vector. Such an observation inspired the new three-step search (NTSS) which has a center-biased search pattern and supports a halfway-stop technique. It is faster on average, and gives better motion estimation as compared to the well-known TSS. Later, the four-step search (4SS) algorithm was introduced to reduce the average case from 21 to 19 search points, while maintaining a performance similar to NTSS in terms of motion compensation errors. We propose a novel unrestricted center-biased diamond search (UCBDS) algorithm which is more efficient, effective, and robust than the previous techniques. It has a best case scenario of only 13 search points and an average of 15.5 block matches. This makes UCBDS consistently faster than the other suboptimal block-matching techniques. This paper also compares the above methods in which both the processing speed and the accuracy of motion compensation are tested over a wide range of test video sequences.

The permanent translocation heterozygote, Rhoeo spathacea shows a characteristic ring of all chromosomes at metaphase-I of male meiosis. Elimination of bivalent formation completely due to extreme heterozygosity poses a special problem for reductional division at meiosis-I where the maternal and the paternal sets need to be separated to different poles. Unlike bivalent meiosis, the functions of SC formation, pairing and recombination required for reductional segregation have to be fulfilled by only telomeres which are the only areas of contact among the chromosomes in the ring. The participation of telomeres in these events assumes significance in view of the balanced lethal gene system imposed by translocation heterozygosity, and the particular requirement that only alternate chromosomes segregated to the same pole results in fertile pollen. This paper throws some light on the telomere functions in R. spathacea in the light of our present understanding of telomere biology. The prospects of using R. spathacea as a model organism to dissect molecular aspects of several telomere related functions are also discussed.

Aim To evaluate the influence of salivary contamination during dentin bonding procedures on shear bond strength and to investigate the effect of contaminant-removing treatments on the recovery of bond strength for two dentin-bonding agents. Materials and methods Seventy-seven human maxillary and mandibular molars were randomly divided into two groups for total-etch adhesive (Single bond-3M ESPE, USA) and self-etch primer (UniFil Bond-GC, Tokyo, Japan) and subjected to contamination with saliva. The data for each group were subjected to one-way analysis of variance (ANOVA) followed by the Student Newman-Keuls test to make comparisons among the groups (p < 0.05). Results Salivary contamination had less adverse effect on the shear bond strength of single bond total-etch adhesive when it was blot dried or washed. UniFil bond was tolerant of salivary contamination, except when contamination occurred after application of the primer. Conclusion In single bond adhesive, when the etched surface is contaminated by saliva, blotting the surface and applying the primer can recover the bond strength. Complete drying of the salivary contaminated surface should be avoided. In the UniFil bond groups, the repriming treatment (UF-V and UF-VI) resulted in the recovery of shear bond strength in the specimens contaminated after priming. Clinical significance The results of this study showed that total- etch adhesive (single bond) was not affected by salivary contamination on the etched surface when the bonding surface was kept moist. Self-etch adhesive (UniFil bond) also tolerated salivary contamination except when the contamination occurred after application of the primer. How to cite this article Justin RM, Paranthaman H, Rajesh AG, Varghese RP, Ranganath LM. Effect of Salivary Contamination on the Bond Strength of Total-etch and Selfetch Adhesive Systems: An in vitro Study. J Contemp Dent Pract 2012;13(5):655-660.

Objective The purpose of this study was to evaluate, using scanning electron microscopy (SEM), the morphological and structural changes of the enamel induced by three bleaching agents namely old McInnes solution, modified McInnes solution and 10% carbamide peroxide gel at different time intervals. Materials and methods Fifteen freshly extracted noncarious human central incisors with intact enamel surface were selected. The teeth were sectioned at the cementoenamel junction separating the crown portion from the root using a diamond separating disk. Following this, the samples were subjected to three different bleaching agents: Group 1: Old McInnes solution, group 2: modified McInnes solution and group 3: 10% carbamide peroxide for a period of 15, 30 and 60 minutes, 24 and 30 hours time interval. The sample stubs were subjected to scanning electron microscope and were photographed at 2000 and 10,000 magnifications. Conclusion The present study revealed no indication of either etching or significant change in surface morphology of enamel when evaluated under scanning electron microscope after 6 weeks treatment with various bleaching agents. Clinical significance Morphological alterations in bleached enamel are both concentration and time dependent. How to cite this article Rajesh AG, Ranganath LM, Kumar KSP, Rao BS. Surface Morphological Changes in Human Enamel Following Bleaching: An in vitro Scanning Electron Microscopic Study. J Contemp Dent Pract 2012;13(3):405-415.

Saliva plays a vital role in oral health as patients strive to maintain a healthy dentition throughout their lives. It is nature's primary defense mechanism for the oral environment, and is particularly important for protecting exposed tooth surfaces. While internal protection for dentin comes from odontoblasts and the dental pulp, the body's external protection for enamel comes from saliva. The noninvasive nature of salivary testing has made it an effective alternative to blood and urine testing and home testing kits have made it possible for people to monitor their own health using this diagnostic medium. This paper presents what saliva can reveal about general and oral health as well as highlights the current use and potential clinical and research applications, of diagnostics based on oral fluids. Clinical significance Early detection always minimizes the need for more invasive treatment. It prevents oral health disease at an early stage and provides a good oral health in rejuvenated state. If you stick and follow regular professional care, prevention maintenance appointments, prevention counseling, good home care and oral hygiene, diet habits you will be free from oral health illness and you can experience the harmonious and rejuvenated state of good oral health. How to cite this article Ranganath LM, Shet RGK, Rajesh AG. Saliva: A Powerful Diagnostic Tool for Minimal Intervention Dentistry. J Contemp Dent Pract 2012;13(2):240-245.

Karyotypes of six species of Barleria L. occurring in South India viz., B. acuminata, B. buxifolia, B. gibsoni, B. involucrata var. elata, B. noctiflora and B. strigosa are studied. All the six species have the same chromosome number of 2n=40. However, each species is distinct in respect of relative positions of centromere, presence/absence and position of satellites and total haploid chromatin length. The diagnostic value of the karyomorphological details in these taxa is discussed.

A central question in biology is how cell fate is specified during development of a multicellular organism. Flowering plants use two major pathways of asymmetric cell divisions in a spatio-temporal manner to achieve required cellular differentiation. In the 'one mother--two different daughters' pathway, a mother cell mitotically divides to produce two daughter cells of different size and fate. By contrast, the 'coenocyte-cellularization' pathway involves formation of a coenocyte, nuclear migration to specific locations of the coenocyte and cellularization of these nuclei by unique wall forming processes. Given that cell fate determinants play a key role in establishing cell identity, their allocation to daughter cells in the two pathways needs to be understood in terms of the unique cell cycle regulatory mechanisms involved. Most of the information available on cell fate determination in flowering plants is in the form of genes identified from mutant analysis. Novel techniques of interrogating individual plant cells in vivo are necessary to advance the extant knowledge from genetics to functional genomics data bases.

A central question in biology is how cell fate is specified during development of a multicellular organism. Flowering plants use two major pathways of asymmetric cell divisions in a spatio-temporal manner to achieve required cellular differentiation. In the 'one mother--two different daughters' pathway, a mother cell mitotically divides to produce two daughter cells of different size and fate. By contrast, the 'coenocyte-cellularization' pathway involves formation of a coenocyte, nuclear migration to specific locations of the coenocyte and cellularization of these nuclei by unique wall forming processes. Given that cell fate determinants play a key role in establishing cell identity, their allocation to daughter cells in the two pathways needs to be understood in terms of the unique cell cycle regulatory mechanisms involved. Most of the information available on cell fate determination in flowering plants is in the form of genes identified from mutant analysis. Novel techniques of interrogating individual plant cells in vivo are necessary to advance the extant knowledge from genetics to functional genomics data bases.

Plant development shows a fascinating range of asymmetric cell divisions. Over the years, however, cellular differentiation has been interpreted mostly in terms of a mother cell dividing mitotically to produce two daughter cells of different fates. This popular view has masked the significance of an entirely different cell fate specification pathway, where the mother cell first becomes a coenocyte and then cellularizes to simultaneously produce more than two specialized daughter cells. The "one mother - two different daughters" pathways rely on spindle-assisted mechanisms, such as translocation of the nucleus/spindle to a specific cellular site and orientation of the spindle, which are coordinated with cell-specific allocation of cell fate determinants and cytokinesis. By contrast, during "coenocyte-cellularization" pathways, the spindle-assisted mechanisms are irrelevant since cell fate specification emerges only after the nuclear divisions are complete, and the number of specialized daughter cells produced depends on the developmental context. The key events, such as the formation of a coenocyte and migration of the nuclei to specific cellular locations, are coordinated with cellularization by unique types of cell wall formation. Both one mother - two different daughters and the coenocyte-cellularization pathways are used by higher plants in precise spatial and time windows during development. In both the pathways, epigenetic regulation of gene expression is crucial not only for cell fate specification but also for its maintenance through cell lineage. In this review, the focus is on the coenocyte-cellularization pathways in the context of our current understanding of the asymmetric cell divisions. Instances where cell differentiation does not involve an asymmetric division are also discussed to provide a comprehensive account of cell differentiation.

This paper reviews the signalling and mobility management issues in wireless ATM networks and explains how some of those issues are addressed in the Wireless ATM Research Project (WARP) (Acharya and Raychaudhury, 1996) using a new approach to network signalling called open signalling (Acharya et al., 1997).

Programmed cell death (PCD) is an integral part of both animal and plant development. In animals, model systems such as Caenorhabditis elegans, Drosophila melanogaster, and mice have shown a general cell death profile of induction, caspase mediation, cell death, and phagocytosis. Tremendous strides have been made in cell death research in animals in the past decade. The ordering of the C. elegans genes Ced-3, 4 and 9, identification of caspase-activated DNase that degrades nuclear DNA during PCD, identification of signal transduction modules involving caspases as well as the caspase-independent pathway, and the involvement of mitochondria are some of the findings of immense value in understanding animal PCDs. Similarly, the caspase inactivation mechanisms of infecting viruses to stall host cell death give a new dimension to the viral infection process. However, plant cell death profiles provide an entirely different scenario. The presence of a cell wall that cannot be phagocytosed, absence of the hallmarks of animal PCDs such as DNA laddering, formation of apoptotic bodies, a cell-death-specific nuclease, a biochemical machinery of killer enzymes such as caspases all point to novel ways of cell elimination. Large gaps in our understanding of plant cell death have prompted speculative inferences and comparisons with animal cell death mechanisms. This paper deals with both animals and plants for a holistic view on cell death in eukaryotes.

Reports on Medical education consistently confirm a cluster of findings regarding primary care and Behavioural medicine: a large percentage of patients with psychosocial problems first present to primary care physicians; managed care and health economics accelerate demands and time constraints; medical students receive few opportunities to develop effective basic skills in establishing therapeutic relationships with patients and measuring progress over time. A unique opportunity occurred to test a new student training model. The course is one year long and built into the required primary care continuity clinic: one half day per week preceptorship. Key features of the curriculum include: orientation to the common behavioural issues, use of brief rating scales for screening and referral, interdisciplinary team training, preceptors teach and monitor the therapeutic process and problem based didactic skills workshops in clinical management. Evaluations include video tape analysis of skills, patient logs, use of psychological rating scales, and end of year tests using performance exams (clinical simulations). Implications for curriculum design and assessment will be discussed.

Two interspecific F1 hybrids of Citrus species were examined for inheritance of leaf phenolic compounds. Both the hybrids revealed a reduced number of compounds compared with those of the parents. In addition, the spot pattern of each taxon offered a basis for analysis of inheritance pattern. Due to the production of clones with a consequent reduction in the number of sexual offspring by nucellar embryony in these plants, the unusual pattern of inheritance observed in the hybrids could not be categorized as either a product of disturbed Mendelian ratios or as transgressive segregation affecting only a few individuals in the segregating generations.

In this paper, Genetic Algorithm (GA) is used for identifying two bioprocesses. Bioprocesses are highly nonlinear systems and hence conventional techniques such as Recursive Least Squares (RLS) cannot be used to identify these systems. Systems chosen for identification are fed batch fermentor and bioreactor. Simulation results are presented for the above cases and are found to be satisfactory.

In the normal fuzzy logic control (FLC) system, both the membership functions and the rule sets are usually decided upon subjectively, case by case. The application of Genetic Algorithm(GA) could lead to proper selection of membership functions and rule base objectively. In this paper, the optimisation of membership functions of a FLC for a fed-batch fermentor is carried out with help of Genetic Algorithm (GA). Results are found to be satisfactory.