Comparitive Evaluation of the Remineralizing Potential of Three Different Dentifrices: An In Vitro study evaluated using Micro CT and Microhardness Testing

This study was done to compare the remineralizing potential of three different remineralizing agents on demineralized tooth surfaces using micro CT and micro hardness evaluation. 45 enamel specimens with buccal surface facing upwards were embedded in acrylic resin blocks and they were divided into 3 groups having 15 specimens in each group. Baseline evaluations of the samples were done following which the specimens were then demineralized using McInne’s demineralizing solution in two cycles. After that remineralization procedure was done in two cycles using Casein phosphopeptide Amorphous calcium phosphate (CPP - ACP), 0.21% sodium fluoride - Tricalcium phosphate (f-TCP) and Calcium Sodium Phosphaosilicate (CSP) containing tooth pastes for groups I,II,III respectively. The specimens were evaluated for micro CT (ScancoTM) and Vicker’s Micro Hardness (SchimadzuTM) testing at baseline, after demineralization cycle 2 and remineralization 1 and 2 cycles for determining the mineral concentration and the surface microhardness respectively. During the entire procedure the specimens were stored in artificial saliva. In micro CT testing, specimens were scanned in horizontal thin sections at 100μm intervals and the digitalized images were captured by a computer at 1024x1024 pixels and the measurements were taken on three different locations and the mean of these measurements were used as the Linear Attenuation Coefficient values of the specimen that was expressed in mg/cm3. In microhardness testing, specimens were placed on the stage of tester, focused with 40x objective lens and a load of 100 g for 14 seconds was applied on the surface of specimen. The indentation formed was measured using the digital software and the average microhardness of the specimen was determined from five indentations and the values were expressed in VHN. The procedure was repeated for all the forty five specimens. Data were analysed statistically using Statistical Package for Social Sciences. (SPSS) version - 10. Data were expressed in its mean and standard deviation and were analysed using One way ANOVA, paired-T test and Post-Hoc Duncan’s Multiple Range test. It was observed that all the three remineralizing agents used in the study significantly increased the LAC and VHN values of the enamel specimens following 15 days and 30 days application. But when the three agents were compared, it was observed that CPP - ACP (Group – 1) showed the better remineralizing potential than the other two agents and there is no statistical significance between f-TCP (Group - II) and CSP (Group – III)

Four-Dimensional Imaging and Radiation Therapy: A Review of Challenges and Advancements in Clinical Practices

4-Dimensional Radiation therapy (4DRT) has been vastly developed in the past two decades. Motion management has become a vital part of high precision radiotherapy, wherein Stereotactic Body Radiation Therapy (SBRT) turns out to be a great boon for treating thoracic and abdominal tumours with confidence. In this review paper, we have analyzed the development of motion management strategies and the advancement of 4DRT.We have discussed the evolution of Internal target volume (ITV), 4D imaging techniques and the problems of breathing motion. In the second part, we have discussed various methods to tackle breathing motion. We also have reviewed the dosimetric aspects of 4D imaging and its clinical implications. In the last section, we have elaborated the 4D radiation therapy and recent advancements and practices.&nbsp

Effects of Fuel Unsaturation on Pollutant Emissions from the Laminar Flames of Prevaporized Petroleum and Biodiesel Blends in Air

Biodiesels, considered as alternative fuels to petroleum diesel, are defined as fatty acid methyl or ethyl esters derived from triglycerides of vegetable oils or animal fats. The utilization of biodiesels reduces greenhouse gas emissions, assists in sustainable energy development, and enhances energy independence due to the renewable and biodegradable nature of these fuels. Besides being close to environmentally carbon-neutral, biodiesels have properties similar to those of petroleum fuels with comparable energy content and can be blended with petroleum fuels and used in existing engines without major modifications. Furthermore, they contain fuel-bound oxygen while being free of aromatic content; therefore, blends of biodiesels and petroleum fuels present the capability of reducing soot emissions from engines. Blending of biodiesels with petroleum fuels is considered feasible in the near term due to limited current availability of the commercial biodiesels and the lack of experience on the long term effects of storage, handling, transportation and combustion of these biodiesels and blends on the engines and the environment. Several studies in engine literature have revealed that the use of biodiesels and their blends in a compression ignition engine resulted in an appreciable reduction in the emissions of particulate matter (PM), unburnt hydrocarbons (UHC) and CO, compared to the use of diesel fuel. However, in case of nitric oxides (NOx) emissions, the results are variable and case dependent. The average effect of biodiesel on NOx emission was seen to be small, but with a high variance, which resulted in difficulty in discerning a clear pattern. Nitric oxides are categorized as one of the key pollutants in engine emissions that can affect human respiratory system and vegetation. Therefore, it is crucial to understand the effect of various fuel and engine operating parameters on biodiesel NOx emissions to develop enhanced mitigation and abatement techniques for the widespread use of biodiesels in transportation. In engine literature, fuel unsaturation has been attributed to the observed change in NOx emissions with the use of biodiesels in compression ignition engines. Several results indicated the existence of a strong relationship between NOx emissions and iodine number, used as a measure of the fuel unsaturation of vegetable oils and fatty acid methyl esters. However, relevance of iodine number as a measure of total unsaturation of petroleum fuels like diesel, Jet A and their blends with biodiesels is debatable due to the significant differences in the reactivity of iodine with petroleum fuels. Bromine number, used as a measure of aliphatic unsaturation in petrofuel samples, does not account for the aromatic unsaturation from petroleum fuels. Hence, a common parameter that is relevant for both biodiesels and petroleum fuels needs to be identified to quantify the fuel unsaturation. A parameter, termed “Degree of Unsaturation (DOU),” which accounts for the total unsaturation of the fuel from all sources such as double and triple bonds, aromatics and other ring structures irrespective of the families of the fuels (alkanes, alkenes, alkynes, aromatics, ether or ester) that has been used in organic chemistry literature is proposed in this work and identified as a potential indicator of NOx emissions from biodiesel blends. In this dissertation work, experimental correlations between DOU and the NO emission index on a mass basis (EINO) in laminar flames of neat prevaporized fuels such as methyl oleate (MO), soy methyl ester (SME), canola methyl ester (CME), rapeseed methyl ester (RME), palm methyl ester (PME), heptane, toluene, diesel, JetA and petroleum/biodiesel blends at various equivalence ratios (Ф = 0.9, 1.0, 1.2 and 1.5) are developed. The NO emission index of flames of biodiesel/petroleum blends was found to increase with DOU, but with varying trends depending on their families of origin. The effects of DOU on EINO were significantly influenced by the equivalence ratio, with the maximum influence at an equivalence ratio of 1.2. At the equivalence ratio (Ф) of 1.2, EINO increased from 2.4 g/kg at a DOU value of 1.7 to 4.4 g/kg at a DOU of 3.0 among biodiesels and their blends with petroleum fuel; toluene flame (100% aromatic content with a DOU of 4) produced an EINO of 6.94 g/kg. It is found that both NO and CO emission indices from the tested flames are influenced by two major parameters - equivalence ratio and total fuel unsaturation. Further, the presence of fuel aromatic content and the family of fuel were observed to significantly influence NOx formation particularly near stoichiometric equivalence ratios. Based on both global and inflame emission results along with the numerical analysis of tested flames, it is concluded that fuel unsaturation, fuel aromatic content, equivalence ratio and family of the respective fuel, together influence the NOx emissions in flames. The net effects of these parameters at a given condition establish the amount of EINO produced from the corresponding flames due to the fuel chemistry effect alone. Hence, DOU provides a common platform to compare and quantify the effects of fuel unsaturation across different fuel families and can be employed as an indicator of NOx emissions. DOU can be evaluated based on the average molecular formula of the fuel alone without involving complex and expensive experimental procedures such as those involved in the measurement of iodine number. The propensity of a biofuel blend for NOx emissions during combustion can be quickly ascertained with the successful development of Degree of Unsaturation (DOU) parameter, thus, providing a valuable tool for fuel developers

Structural interrogation of phosphoproteome identified by mass spectrometry reveals allowed and disallowed regions of phosphoconformation

High-throughput mass spectrometric (HT-MS) study is the method of choice for monitoring global changes in proteome. Data derived from these studies are meant for further validation and experimentation to discover novel biological insights. Here we evaluate use of relative solvent accessible surface area (rSASA) and DEPTH as indices to assess experimentally determined phosphorylation events deposited in PhosphoSitePlus. Based on accessibility, we map these identifications on allowed (accessible) or disallowed (inaccessible) regions of phosphoconformation. Surprisingly a striking number of HT- MS/MS derived events (1461/5947 sites or 24.6%) are present in the disallowed region of conformation. By considering protein dynamics, autophosphorylation events and/or the sequence specificity of kinases, 13.8% of these phosphosites can be moved to the allowed region of conformation. We also demonstrate that rSASA values can be used to increase the confidence of identification of phosphorylation sites within an ambiguous MS dataset. While MS is a stand-alone technique for the identification of vast majority of phosphorylation events, identifications within disallowed region of conformation will benefit from techniques that independently probe for phosphorylation and protein dynamics. Our studies also imply that trapping alternate protein conformations may be a viable alternative to the design of inhibitors against mutation prone drug resistance kinases

PHYTOCHEMICAL SCREENING, GAS CHROMATOGRAPHY-MASS SPECTROMETRY (GC-MS) ANALYSIS OF PHYTOCHEMICAL CONSTITUENTS AND ANTIBACTERIAL ACTIVITY OF CORIANDRUM SATIVUM (L) SEEDS

Objective: The present study was carried out to evaluate the phytochemical screening, Gas Chromatography–Mass Spectrometry analysis of phyto-constituents and antibacterial activity of Coriandrum sativum (L.) seeds against the bacterial [Microbial Type Culture Collection (MTCC)] strains.Methods: Methanol, ethanol, ethyl acetate, acetone and water extracts of Coriandrum sativum (L) seeds were prepared using the Soxhlet apparatus. The antibacterial activity of various extracts of C. sativum seeds were identified by disc diffusion method against bacterial strains. The bioactive components of methanol and acetone fraction of C. sativum seeds were evaluated by Gas Chromatography-Mass Spectrometry (GC-MS) analysis. The minimal inhibitory concentration (MIC) values were obtained by the well diffusion method between the ranges of 1000µg/ml to 7.8µg/ml.Results: The preliminary phytochemical screening of various extracts of C. sativum revealed the presence of different Phyto-constituents. Methanol extract of C. sativum showed the maximum inhibition zone (20 mm) against Staphylococcus aureus and followed by Klebsiella pneumoniae (17 mm). The MIC values of methanol extract were found to be 62.5µg/ml against Staphylococcus aureus, Proteus mirabilis and Bacillus subtilis. In the GC-MS analysis of phyto-compounds, the methanol extracts showed fourteen bioactive fractions and eleven compounds from acetone extract.Conclusion: The methanol and acetone extracts of Coriandrum sativum seeds showed maximum inhibitory activity against the tested bacterial strains.Â

Mahimahi: A Lightweight Toolkit for Reproducible Web Measurement

This demo presents a measurement toolkit, Mahimahi, that records websites and replays them under emulated network conditions. Mahimahi is structured as a set of arbitrarily composable UNIX shells. It includes two shells to record and replay Web pages, RecordShell and ReplayShell, as well as two shells for network emulation, DelayShell and LinkShell. In addition, Mahimahi includes a corpus of recorded websites along with benchmark results and link traces (https://github.com/ravinet/sites). Mahimahi improves on prior record-and-replay frameworks in three ways. First, it preserves the multi-origin nature of Web pages, present in approximately 98% of the Alexa U.S. Top 500, when replaying. Second, Mahimahi isolates its own network traffic, allowing multiple instances to run concurrently with no impact on the host machine and collected measurements. Finally, Mahimahi is not inherently tied to browsers and can be used to evaluate many different applications. A demo of Mahimahi recording and replaying a Web page over an emulated link can be found at http://youtu.be/vytwDKBA-8s. The source code and instructions to use Mahimahi are available at http://mahimahi.mit.edu/

Classification of Metals used in the Sand Casting Process

The Sand Casting Process And The Different Methods Used To Cast The Metals Are The Subjects Of This Paper. Casting Is A Manufacturing Process For Creating Complex Material Shapes. A Large Classification Is Needed To Understand The Metals Used By Researches, Why They Were Used, And What The Most Commonly Used Metal For Their Research Is. We Studied And Understanded The Various Types Of Sand Casting Processes Used By The Researchers In This Review Paper. And We Categorized And Graded All The Papers We Reviewed And Classified Based On Their Respective Study Areas And Material Use