Anti-microbial efficacy of root canal preparation in deciduous teeth with manual and rotary files: A randomized clinical trial.

Background: In a pulpectomy, the eradication of microbes from the primary root canal is accomplished through biomechanical preparation, which could be carried out with either manual or rotary instruments. Aims: The objective of this clinical trial was to evaluate the efficiency of manual K-files, H-files, and Kedo-S Square rotary files in reducing microbial flora after canal preparation in primary molars. Materials and Methods: This randomized clinical trial consisted of 45 primary molars requiring pulpectomy. The teeth were randomly allocated to one of the three groups: Group I: Manual K-files, Group II: Manual H-files, and Group III: Kedo-S Square rotary files, based on the type of instrumentation. Pre-and Post-instrumentation sampling was performed using clean absorbent paper points and kept in a clean Eppendorf tube having thioglycolate broth as the transport medium. Culturing was performed on agar media from which both aerobic and anaerobic microbial counts were estimated. Collected data were statistically analyzed using one-way analysis of variance (ANOVA) and Wilcoxon signed-rank test. Following root canal preparation, 87-89% reduction of the aerobic and anaerobic microbial load was noted in group I, whereas it was an 89-92% reduction in group II and a 93-95% reduction in group III. Results: Biomechanical preparation with Kedo-S Square rotary file showed higher efficacy in microbial reduction compared to manual instrumentation. Conclusion: Manual and rotary files were equally effective in removing root canal microbes. Biomechanical preparation with a KedoS Square rotary file resulted in greater microbial efficacy. Hence In children, effective root canal cleaning in a short period of time is a major consideration.

Using Citation Context to Improve the Retrieval of Research Article from Cancer Research Journals

Objective: In recent years, citation analysis tools provide many devices for finding or computing the citation score or impact factor for journals. It is important for the researchers to identify good journals for collecting research ideas discussed. A journal with a good impact factor value is preferably referred to by many researchers. In this research work, the author proposes a system for ranking journals on the basis of ideas and results cited in other papers. Methods: The work involves the cited content extractor for extracting the descriptive features mentioned about the cited paper. The cited content refers to the content in the article written by a citing paper and relating to the cited paper. The ranking system uses a citation score estimator for computing the overall weight of the descriptive cited content relating to a specific paper in the citing papers. The journal ranking system performs classification of the citation content with the evaluation of a citation score. The work that involves the citation content is classified under different categories as positively cited, negatively cited or neutral and unrelated. Results: Then the computed citation score is used for ranking the dealing with research on cancer research journals. The results of the ranking journals indicate that the particular ranked journal has been cited in the literature of many journals with a good descriptive content. Journal ranking system can be considered as a well-organized tool for ranking the cancer research scientific journal based on citation content and citation counting. Conclusion: This experimental cancer journal ranking method increases accuracy and effectiveness by using the citation content when compared with PageRank and HITS.

Comparison of the flow properties of aqueous suspension corticosteroid nasal sprays under differing sampling conditions.

Many aqueous suspension corticosteroid nasal sprays become less viscous when shaken and sprayed, then return to a more viscous state after application. This time-dependent, reversible loss of viscosity under shear (e.g., shaking or spraying) can be quantified in the rheological property of thixotropy. The flow properties of 5 corticosteroid nasal sprays were measured over a range of shear rates. The formulations tested included Nasonex, Vancenase AQ, Nasacort AQ, Rhinocort Aqua, and Flonase. The yield stress values, as well as an estimate of thixotropy, were compared by using three different sampling techniques, including one that simulated patient use (shaking for 30 sec, spraying, and immediately transferring the sample to the rheometer). The rheological properties of all products indicated that when initially shaken and dispensed, they flowed more freely, followed by recovery of viscosity that would likely inhibit the suspensions from flowing out of the nasal cavity. Under all three tested conditions, Nasonex exhibited the highest yield stress, the largest apparent initial and final viscosities, and the highest apparent thixotropy. The study protocol that simulated patient-use conditions produced the following rank order of measured thixotropy: Nasonex > Flonase > Vancenase AQ > Rhinocort Aqua > Nasacort AQ. The thixotropy of Nasonex was 3.4 to 21.4 times greater and the final viscosity was 3.2 to 17.4 times greater than the values of the other tested products.

Effect of metformin on nitric oxide synthase in genetically obese (ob/ob) mice.

Genetically obese (ob/ob) mice were employed for the study of the effect of metformin on activity and expression of nitric oxide synthase (NOS ) in vitro and in vivo. For in vitro analysis, mouse liver extracts were used. For the in vivo study, (ob/ob) and their control litter mates (ob/c) mice were injected with specified amounts of metformin and the expression of NOS in the adipose tissue and hypothalamus was measured by Western blotting. Results show that metformin exhibited a biphasic effect on NOS activity in vitro. Expression of metformin was differentially altered in the hypothalamus and adipose tissues of the normal and ob/ob animals that were treated with metformin. Further, a significant decrease in food intake occurred in the (ob/ob) mice that received metformin. This decrease in food intake was not accompanied by changes in serum glucose. At inhibitory concentrations, hypothalamic NOS expression changes differentially in normal and ob/ob mice. In normal mice, metformin stimulated NOS expression, while in ob/ob mice there was an inhibition. NOS expression increased in brown adipose tissue of metformin treated control mice, while no such increase was observed in ob/ob mice. No effect of metformin was observed in white adipose tissue of control or obese mice. Thus, metformin may produce anorectic effects through modulation of NOS.

A study of Malaiyur village ecosystem of Madurai district, Tamil Nadu (India).

The interaction between man and environment in Malaiyur, a hilly village of Madurai District (Tamil Nadu) was studied during the year 1998. The village is sustained on agriculture labour and hence occupies the lowest hierarchy with traditional occupation and the people may be categorised as 'ecosystem people'. The study suggests that the people has to be changed as 'Biosphere people' to protect the environmental degradation due to human activities.

Chaos in thermal pulse combustion.

An experimental thermal pulse combustor and a differential equation model of this device are shown to exhibit chaotic behavior under certain conditions. Chaos arises in the model by means of a progression of period-doubling bifurcations that occur when operating parameters such as combustor wall temperature or air/fuel flow are adjusted to push the system toward flameout. Bifurcation sequences have not yet been reproduced experimentally, but similarities are demonstrated between the dynamic features of pressure fluctuations in the model and experiment. Correlation dimension, Kolmogorov entropy, and projections of reconstructed attractors using chaotic time series analysis are demonstrated to be useful in classifying dynamical behavior of the experimental combustor and for comparison of test data to the model results. Ways to improve the model are suggested. (c) 1995 American Institute of Physics.