Synthesis and characterization of targeted bar encapsulated polylactic-co-glycolic acid nanoparticles to inhibit porphyromonas gingivalis biofilm formation.

Periodontal disease is one of the most prevalent infectious diseases worldwide. Between 30-50% of the global adult population suffers from periodontal disease. Some form of periodontitis is present in 46% of American adults, corresponding to annual expenditures in excess of 14 billion dollars for treatment and prevention. Current treatments for periodontal diseases involve mechanical removal of plaque, correction of risk factors, gingival surgery and/or antibiotic therapy. To our knowledge there is no effective therapeutic approach that aims to limit pathogen colonization of the oral biofilm or re-colonization after treatment. Interaction of the pathogen Porphyromonas gingivalis with oral streptococci is critical in the pathogenesis of periodontal diseases. Our previous studies identified a peptide (BAR) that potently inhibited this interaction and reduced P. gingivalis virulence in vivo. However, BAR required higher concentrations and prolonged exposure in limiting P. gingivalis in a pre-established biofilm. This study is aimed at developing targeted BAR encapsulated poly(lactic-co-glycolic acid; PLGA) nanoparticles (NPs) to increase the efficacy of BAR to inhibit P. gingivalis colonization in a dual species biofilm. NPs encapsulating BAR were synthesized using double emulsion solvent evaporation technique. We generated NPs with particle size of 207±19 nm and zeta potential of -15mV. Loading and controlled release properties of NPs were determined using a fluorescently labeled BAR. We showed that BAR-NPs had a total payload of 14.12±0.39 µg/mL of BAR per mg of NP, resulting in the sustained-release of BAR for up to 4 hours. Furthermore, NPs encapsulating BAR peptide potently inhibited pre-formed P.gingivalis/ S. gordonii biofilm. These results suggest that enhanced inhibition of P. gingivalis was be obtained with BAR-NPs, identifying a novel therapeutic approach to effectively targeting P. gingivalis colonization of the oral cavity

The relationship between job burnout, organizational justice, transformational leadership and job performance among SJKT teachers in Perak

This study aims to examine the factors that affect job performance among teachers in Sekolah Jenis Kebangsaan Tamil (SJKT). The aim of the study was: (a) to determine whether job burnout affects the job performances (JP) of teachers in Sekolah Jenis Kebangsaan Tamil (SJKT) schools in Perak; (b) to determine whether organization justice (OJ) affects the teachers’ job performance; (c) to determine the leadership style (transformational) influences in the job performances of teachers. For the aim of this study, teachers from this school, about 105 teachers were selected as sample. To achieve this objective, data were collected by means of a questionnaire that examined various aspects of the job performances. Analysis of the data revealed that job burnout, organization justice, and the transformational leadership (TL) style varies greatly depending on the teachers output of the Sekolah Jenis Kebangsaan Tamil (SJKT) schools in Perak. Finally, based on the research results, the enlightenment of this research to the theoretical and practical contributions is discussed and suggestions for future research are put forward

Analysis of 200 cases of conduction disturbances in acute ST elevation Inferior wall myocardial infarction related to causal comparison

INTRODUCTION: Conduction defects are one of the immediate complications which occur following acute myocardial infarction .various Types of conduction defects occur during acute myocardial infarction. Atrioventricular blocks are more commonly associated with inferior wall myocardial infarction. Inferior wall myocardial infarction account for 40-50% of all acute myocardial infarction. Acute myocardial infarction associated with conduction disturbances means mortality and morbidity increases. Early recognition and prompt treatment will definitely reduce mortality. AIM: To analyze 200 cases of conduction disturbances in patients with acute ST elevation inferior wall myocardial infarction related to causal comparisons like Age, sex, smoking, alcoholism, hypertension, diabetes mellitus, total cholesterol , HDL, LDL level and COPD patients. To find out any association of each comparison group with ST elevation inferior wall myocardial infarction particularly on the risk of conduction disturbances. MATERIALS AND METHODS: In this observational cross sectional study. Total of 200 patients of acute inferior wall myocardial infarction with conduction disturbances admitted in intensive care unit of Coimbatore medical college hospital during one period from July 2016 June 2017. All the 200 cases were selected according to inclusion criteria. A proforma was used to record to obtain typical symptoms and risk factors. History of hypertension, diabetes, smoking, alcoholism, dyslipidemia and COPD were noted. To find out any association of each comparison group with ST elevation inferior wall myocardial infarction particularly on the risk of conduction disturbances. RESULTS: Total of 200 cases 37% of patients were in the age group of 61-70.34.5% of patients were 51-60 years of age. Male predominant. Smoking and alcoholic group > 55%.Hypertension and Diabetes mellitus are the important risk factor which is statistically significant. But dyslipidemia and COPD are not significantly correlated with conduction disturbances. Mean value of dyslipidemia was correlated with prognosis of the patient. CONCLUSION: Among the conduction disturbances sinus bradycardia is the commonest conduction disturbances followed by first degree heart block then complete heart block and second degree heart block. When Age increases conduction disturbances increases with male predominant. Hypertension and Diabetes mellitus are important and significant risk factor for conduction disturbances. Among hospital mortality sinus bradycardia group had high mortality because of need for immediate pacemaker. There is significant correlation between mean value of dyslipidemia and prognosis of conduction disturbances

Effective algorithms for pickup and delivery problem with loading restrictions and handling costs

The Pickup-and-Delivery problem is an important category of Vehicle Routing Problem with a lot of practical applications. In practice, the problems in this category often have to be solved with cargo loading/unloading restrictions. For example, shippers may incur cargo handling costs if a driver has to unload and reload pallets into the vehicle at shipment delivery sites. However, this cost can be eliminated by following the Last-In-First-Out (LIFO) order for cargo loading/unloading. Motivated by this application, we explore the Pickup-and-Delivery Problem (PDP) with LIFO loading restrictions in single and multi-vehicle settings. We also study the PDP with handling costs in single and multi-vehicle settings because strictly imposing the LIFO order might force the vehicles to travel long distances. For single-vehicle problems, we present multiple mathematical models and branch-and-cut algorithms. We also introduce new inequalities, warm start, and bound tightening procedures to enhance the scalability of our implementations. The multi-vehicle problems are formulated and solved with many practical considerations including vehicle capacity, customer time windows, and maximum on-road time for drivers. We also propose new heuristic algorithms which were very effective in solving the multi-vehicle problems. This dissertation also introduces new conditional integral separation procedures which could be applicable in large scale mathematical models outside the vehicle routing discipline

Decomposition Algorithms for the Elementary Shortest Path Problem in Networks Containing Negative Cycles

The Elementary Shortest Path Problem in Networks containing Negative Cycles (ESPPNC) is an NP-hard problem. Although there are exact formulation approaches to solve the ESPPNC, a decomposition setting for this problem has not been explored. In this thesis, two Decomposition and Branch-and-Cut (DBC) algorithms to solve the ESPPNC in directed networks are proposed. A master relaxation of the ESPPNC is presented and later strengthened by adding negative cycle elimination constraints in a branch-and-bound framework. The scalability of these approaches is analyzed by extracting their running times on two different test-beds. Also, the performance of these approaches is compared against the performance of an exact formulation on the same test-beds. From the results, the DBC approaches are able to solve all the instances much faster than the exact formulation approach, so the DBC algorithms scale much better than direct formulation in these test-beds. However, a pathological instance is also identified for which the direct formulation is the favorable approach.Industrial Engineering & Managemen

HOMOLOGY MODELING AND IN SILICO DOCKING ANALYSIS OF HUMAN MITOCHONDRIAL THYMIDINE KINASE 2 USING GRID-BASED LIGAND DOCKING WITH ENERGETICS

Objective:Mitochondrial disorders linked to Thymidine Kinase 2 (TK2) deficiency is associated to long term treatment with antiviral nucleoside analogues such as AZT (AZidoThymidine). The accumulation of AZT-TP (AZidoThymidine-TriPhosphate) is suggested to affect DNA polymerase, resulting in mtDNA (mitochondrial DNA) depletion. Thus a potent and selective inhibitor for TK2 is essential to be predicted. Methods: The human mitochondrial TK2was modeled usingModeller and the structure was evaluated using Ramachandran plot. The ligand molecule of both the derivatives of deoxythymidine and thioureawere optimized usingChemsketch and were further docked using GLIDE Schrödinger package 2009. Results: The docking results of both Deoxythymidine and Thiourea derivatives against the target TK2 were analyzed to find the ligands with good dock score and Glide energy. The ligands were selected and induced fit docking of both the derivatives were carried out and the interactions were observed usingPyMol. Conclusion: The present study indicates that deoxythymidine derivatives interact significantly and hence serve as selective inhibitors against Human Mitochondrial TK2. Â&nbsp

Spin-valley locking for in-gap quantum dots in a MoS2 transistor

Spins confined to atomically-thin semiconductors are being actively explored as quantum information carriers. In transition metal dichalcogenides (TMDCs), the hexagonal crystal lattice gives rise to an additional valley degree of freedom with spin-valley locking and potentially enhanced spin life- and coherence times. However, realizing well-separated single-particle levels, and achieving transparent electrical contact to address them has remained challenging. Here, we report well-defined spin states in a few-layer MoS$_2$ transistor, characterized with a spectral resolution of $\sim{50~\mu}$eV at ${T_\textrm{el} = 150}$~mK. Ground state magnetospectroscopy confirms a finite Berry-curvature induced coupling of spin and valley, reflected in a pronounced Zeeman anisotropy, with a large out-of-plane $g$-factor of ${g_\perp \simeq 8}$. A finite in-plane $g$-factor (${g_\parallel \simeq 0.55-0.8}$) allows us to quantify spin-valley locking and estimate the spin-orbit splitting ${2\Delta_{\rm SO} \sim 100~\mu}$eV. The demonstration of spin-valley locking is an important milestone towards realizing spin-valley quantum bits.Comment: 7 pages, 3 figure

Experimental investigation on split type window Air conditioner using HFC and HC mixture as ecofriendly refrigerant alternate to HCFC-22

This paper reports on an experimental study evaluating a window air conditioner's performance when R152a/R290/R600/R600a refrigerant mixture (by various mass percentages) is used as a possible alternative to R-22. Alternative refrigerants are local, cheap, and environmentally friendly. Unmodified R-22 window AC was charged with R152a/R290/R600/R600a. During the experiment, parameters such as coefficient of performance, refrigeration effect, pressure ratio, compressor discharge temperature, refrigerant mass flow rate, and compressor power are analyzed. The present work shows that R152a-15%/R290-15%/R600-35%/R600a-35% is the best-performing alternative refrigerant. Proposed blends and R22's performance were compared