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Data Dependant Learners Ensemble Pruning  [cached]
Gang Zhang,Jian Yin,Xiaomin He,Lianglun Cheng
Journal of Software , 2012, DOI: 10.4304/jsw.7.4.919-926
Abstract: Ensemble learning aims at combining several slightly different learners to construct stronger learner. Ensemble of a well selected subset of learners would outperform than ensemble of all. However, the well studied accuracy / diversity ensemble pruning framework would lead to over fit of training data, which results a target learner of relatively low generalization ability. We propose to ensemble with base learners trained by both labeled and unlabeled data, by adopting data dependant kernel mapping, which has been proved successful in semi-supervised learning, to get more generalized base learners. We bootstrap both training data and unlabeled data, namely point cloud, to build slight different data set, then construct data dependant kernel. With such kernels data point can be mapped to different feature space which results effective ensemble. We also proof that ensemble of learners trained by both labeled and unlabeled data is of better generalization ability in the meaning of graph Laplacian. Experiments on UCI data repository show the effectiveness of the proposed method.
Diabetes and periodontitis  [cached]
Deshpande Kalyani,Jain Ashish,Sharma RaviKant,Prashar Savita
Journal of the Indian Society of Periodontology , 2010,
Abstract: The main aim of this review is to update the reader with practical knowledge concerning the relationship between diabetes mellitus and periodontal diseases. Exclusive data is available on the association between these two chronic diseases till date. Articles published on this relationship often provide the knowledge of definitions of diabetes mellitus and periodontal diseases, prevalence, extent, severity of periodontal disease, complications of diabetes along with the possible underlying mechanisms. The authors reviewed human epidemiological studies, cross-sectional observations and longitudinal cohort, case control that evaluated variables exclusively over the past 30 years and the predominant findings from the "certain" articles are summarized in this review. This review clarifies certain queries such as 1) Do periodontal diseases have an effect on the metabolic control of diabetes? 2) Does diabetes act as a risk factor of periodontitis? 3) What are the possible underlying mechanisms relating the connection between these two chronic diseases? 4) What is the effect of periodontal intervention on metabolic control of diabetes? After a thorough survey of literature, it was observed that diabetes acts as a risk factor in development of periodontitis as periodontitis is significantly aggravated in patients suffering from diabetes having long term hyperglycemia. Different mechanisms underlying the association between the accelerated periodontal disease and diabetes are emerging but still more work is required. Major efforts are required to elucidate the impact of periodontal diseases on diabetes. At the same time, patients are needed to be made aware of regular periodontal maintenance schedule and oral hygiene.
Periodontitis in HIV patients  [PDF]
Oseeva А.О.,Soboleva L.A.,Bulkina N.V.,Shuldyakov A. A.
Saratov Journal of Medical Scientific Research , 2011,
Abstract: The article presents the study of formation mechanisms and periodontitis course in patients with subclinical stage of HIV-infection. The examination of 45 patients has enabled the division of patients into three basic groups: patients with periodontitis and HIV-infection; patients with periodontitis; and HIV patients without periodontitis. It has been determined that the patients with periodontitis and subclinical HIV-infection have developed local inflammatory reaction with infection, activation of anti-inflammatory cytokines in parodontal recess fluid. It has been proved that the causative factor of frequent and durable relapses in parodontal pathology with clinical HIV-infection was the development of pathologic process with endotoxicosis syndrome and imbalance of lipid peroxidation and antioxidant system
Periodontitis in patients with focal tuberculosis  [PDF]
Alexandrova Е.А.,Lepilin A.V.,Kazimirova N.E.,Shuldyakov А.А.
Saratov Journal of Medical Scientific Research , 2010,
Abstract: The research goal is to investigate the mechanisms of formation and peculiarities of periodontitis in patients with focal tuberculosis. Patients with periodontitis and focal tuberculosis are proved to develop local inflammatory reaction with increased infection and activation of proinflammatory cytokines in parodontal pockets fluid. The main risk factor of frequent and durable recurrence of parodontal pathology in case of focal tuberculosis was the development of pathologic process as a cause of disbalance of lipid peroxidation and antioxidant system, endotoxicosis syndrome
The Relationship between Diabetes Mellitus and Periodontitis
Al Ameen Journal of Medical Sciences , 2011,
Abstract: Chronic gingivitis and periodontitis are common inflammatory conditions of the periodontal tissues. Given the ‘right’ concurrence of risk factors, a person with periodontitis can experience significant destruction of tooth-supporting bone, ultimately resulting in tooth loss. Poorly controlled diabetes is an important risk factor for periodontitis, and gingivitis and periodontitis are sometimes the first sign that a patient has diabetes. As severe periodontitis can lead to the loss of teeth, it is important that patients with diabetes practise good oral hygiene and have regular dental check-ups so that problems can be detected quickly
Evaluation of telomerase expression in chronic periodontitis  [cached]
Balaji T,Vettriselvi V,Paul Solomon,Rao Suresh
Indian Journal of Dental Research , 2010,
Abstract: Background : Human telomerase is a multi subunit ribonucleoprotein enzyme concerned with telomeric lengthening and homeostasis in man. This enzyme has been found to be elevated in inflammatory conditions like rheumatoid arthritis and silica injury lung. Since chronic periodontitis is also an inflammatory condition where immune cells and cytokines mediate tissue destruction, we set out to evaluate telomerase in gingival tissue samples from healthy subjects and chronic periodontitis patients by reverse transcriptase polymerase chain reaction. Materials and Methods : Gingival biopsies were obtained from eight healthy subjects and eight chronic periodontitis patients. Reverse transcriptase polymerase chain reaction (RTPCR) was carried out to evaluate telomerase gene expression in the samples. Results : None of the healthy gingival tissue samples expressed the telomerase gene while all the chronic periodontitis samples expressed it. The severe chronic periodontitis samples expressed the gene more intensely than the moderate chronic periodontitis samples. Conclusion : Various mechanisms have been explained to account for telomerase elevation in chronic periodontitis .This study helps us understand the role of telomerase in the pathogenesis of periodontal disease. It could be concluded that telomerase could be used as a marker to assess the severity of inflammation in chronic periodontitis.
Cosmic String in the BTZ Black Hole Background with Time-Dependant Tension  [PDF]
J. Sadeghi,H. M. Farahani,B. Pourhassan,S. M. Noorbakhsh
Physics , 2009, DOI: 10.1016/j.physletb.2011.07.054
Abstract: In this paper, we study the equation of circular loops with time-dependant tension in the BTZ black hole background. We obtain various cases where cosmic string loops finally collapse to form black holes. Also, we study effect of the BTZ black hole mass and angular momentum on the evolution of cosmic string loops. We find the critical values of initial radii as a limit for the cosmic string loops collapsing to form black holes.
Gene Polymorphisms in Chronic Periodontitis  [PDF]
Marja L. Laine,Bruno G. Loos,W. Crielaard
International Journal of Dentistry , 2010, DOI: 10.1155/2010/324719
Abstract: We aimed to conduct a review of the literature for gene polymorphisms associated with chronic periodontitis (CP) susceptibility. A comprehensive search of the literature in English was performed using the keywords: periodontitis, periodontal disease, combined with the words genes, mutation, or polymorphism. Candidate gene polymorphism studies with a case-control design and reported genotype frequencies in CP patients were searched and reviewed. There is growing evidence that polymorphisms in the IL1, IL6, IL10, vitamin D receptor, and CD14 genes may be associated with CP in certain populations. However, carriage rates of the rare -allele of any polymorphism varied considerably among studies and most of the studies appeared under-powered and did not correct for other risk factors. Larger cohorts, well-defined phenotypes, control for other risk factors, and analysis of multiple genes and polymorphisms within the same pathway are needed to get a more comprehensive insight into the contribution of gene polymorphisms in CP. 1. Introduction Periodontitis like many other common diseases (e.g., Crohn’s disease, cardiovascular diseases, diabetes) is considered to be a complex multifactorial disease. Typical for complex human diseases is that they mostly have a relatively mild phenotype and are slowly progressing and chronic in nature. Furthermore, these diseases are of relative late of onset (i.e., postjuvenile or adult onset) and are relatively common. The phenotype of the complex diseases is determined by both genetic and the environmental factors that affect the individual. Although pathogenic bacteria and various other environmental factors (e.g., smoking and stress) [1] are involved in pathogenesis of periodontitis, also genetic factors are evidenced in the aetiology of periodontitis [2, 3]. Understanding of the interplay between the host and oral bacteria is essential to the understanding of the pathogenesis of periodontal disease. Periodontopathic bacteria initiate and repeatedly attack the host, which subsequently reacts with immune response and may slowly destruct by the action of the inflammatory process itself. However, the presence of pathogenic subgingival bacteria alone does not result in periodontal destruction in most cases. Therefore, although bacteria are essential for the initiation of periodontitis, the amount of plaque and the species of bacteria does not necessarily correlate with disease severity [4]. Each person may have an individual dose dependend response to the bacterial challenge that determines his/her susceptibility to
Experimental chronic periodontitis morphogenesis  [PDF]
Schneider S.A.
Морфолог?я , 2011,
Abstract: Morphogenesis of periodontium tissue in a model of chronic periodontitis was studied. Adult Wistar rats wereused in a model; chronic periodontitis was developed through mastication-related loading decrease. Histological assessmentof periodontium tissue was conducted at Days 7, 14, 21 and 30. It was demonstrated that dystrophic tissue changes prevailover the inflammatory one in this particular experimental model. The structural elements of periodontium were involved intothe pathologic process in the following sequence: gingival mucosa connective tissue – Day 7, gingival epithelium – Day 14;periodontium of the tooth-gingival connection area – Day 21; bone tissue of the alveolar process of the jaw – Days 21-30.Inflammation was manifested at Day 30, only in areas of tooth-gingival connection.
Katiyar Aviral,Prajapati S.K.,Akhtar Ali,Gautam Ambarish
International Research Journal of Pharmacy , 2012,
Abstract: Periodontitis is an inflammatory disease of the supporting tissues of the teeth caused by groups of specific microorganisms. Aggressive forms of periodontitis can be localized or generalized. The concept that localized problem sites may be treated by local drug delivery appears attractive as the antimicrobial agent is delivered within periodontal pockets and the therapy is targeted on specific pathogenic microorganisms. This review highlights the use of mucoadhesive polymers in buccal drug delivery. Advantages associated with buccal drug delivery have rendered this route of administration useful for a variety of drugs. Characterization of critical properties such as the mucoadhesive strength, drug content uniformity, and permeation rate represent the major research areas in the design of buccal films. The present review describe approaches for local prevention of bacterial infections based on antibiotic-eluting medical devices.
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