EMC/FDTD/MD simulation of carrier transport and electrodynamics in two-dimensional electron systems

We present the implementation and application of a multiphysics simulation technique to carrier dynamics under electromagnetic excitation in supported two-dimensional electronic systems. The technique combines ensemble Monte Carlo (EMC) for carrier transport with finite-difference time-domain (FDTD) for electrodynamics and molecular dynamics (MD) for short-range Coulomb interactions among particles. We demonstrate the use of this EMC/FDTD/MD technique by calculating the room-temperature dc and ac conductivity of graphene supported on SiO2.Comment: Part of JCEL special issue on Multiscale and Multiphysics Modelin

Screening for Antibacterial Activity of Andrographis paniculata Used in Malaysian Folkloric Medicine: A Possible Alternative for the Treatment of Skin Infections

In this study non-polar (dichloromethane) and polar (MeOH & aqueous) extracts of A. paniculata (whole plant) were evaluated for in vitro antibacterial activity against 12 skin disease causing bacterial strains (7 gram positive strains; Staphylococcus saprophyticus, Staphylococcus epidermis, Staphylococcus aureus, Streptococcus pyogenes, Bacillus anthracis, Micrococcus luteus, Enterococcus faecalis) and 5 gram negative strains; Proteus mirabilis, Proteus vulgaris, Klebsiella pneumoniae, Neisseria meningitis, Pseudomonas aeruginosa ) using the disc diffusion method at three concentrations; 1000, 500, and 250 μg/disc respectively in order to ascertain its folkloric claim to treat skin infections. The extracts showed significant antibacterial activities against both the Gram-positive and Gram-negative bacterial strains tested. Highest significant antibacterial activity was exerted by the MeOH extract against E. faecalis at 1000 μg/disc (24.00 ± 0.00 mm) and the least activity by the DCM extract against N. meningitis at 250 μg/disc (6.00 ± 0.00mm). The minimum inhibitory concentration ranged between 150 μg /mL and 300 μg /mL depending on microorganism and various extracts. Presence of phytochemicals such as terpenoids, tannins, flavonoids, saponins, alkaloids, amino acids and steroids were observed. These results candidly suggest the presence of promising antibacterial substances in the polar as well as non-polar extracts which could be potential phytomedicine for the treatment of skin infections caused by pathogenic bacterial strains. These findings explicitly support its traditional claims and form a strong basis for further efforts to explore A. paniculata’s antibacterial potential to treat skin frailties efficaciously. Our results confer the utility of this plant extracts in developing a novel broad spectrum antimicrobial agent

Geochemical investigations of a Portion Obu Hill Marble Deposit Okpella, Edo-State, Nigeria

The Obhu marble deposit is located at latitude 7o 21´ 31.2´´ to 7o 21´ 34.9´´ and longitude 6o 25´ 11.6´´ to 6o 25´ 18.0´´. The geochemical investigations of a portion of the Obhu hill marble deposit was aimed at investigating the reserve estimate in tonnage, rock mass/overburden volume and the geochemical composition of the deposit. This study was conducted by using vertical electrical sounding (VES) geophysical method to obtain the geo-electric parameters of the deposit, and to determine the reserve estimate of the Marble deposit of study area. The result shows that the reserve tonnage is 4.6 x 106 Tons and rock mass reserve/overburden volume ratio is 9:1.The chemical analysis were compared with the RMRDC of Nigeria for each element suitable for production of cement, fertilizer, iron, steel and other industrial uses. The MgO values of the samples 1 and 2 does not falls within the acceptable value of 6 % of RMRDC, with the exception of sample 3 which falls within the acceptable limit. CaO, Al2O3 and P2O5 values of the samples falls within the acceptable limits of RMRDC and so suggest that the marble can be put to industrial use, while the Fe2O3 content of sample 2 and 3 makes them probably not best suited for industrial use, except for sample 1 having a lower value of 1.85 %. The silica SiO2 content values for the three samples exceeded the recommended standard of RMRDC of 5 %. This result reveals that the marble deposit is suitable for most industrial use

Oxytocin increases eye contact during a real-time, naturalistic social interaction in males with and without autism.

Autism spectrum conditions (autism) affect ~1% of the population and are characterized by deficits in social communication. Oxytocin has been widely reported to affect social-communicative function and its neural underpinnings. Here we report the first evidence that intranasal oxytocin administration improves a core problem that individuals with autism have in using eye contact appropriately in real-world social settings. A randomized double-blind, placebo-controlled, within-subjects design is used to examine how intranasal administration of 24 IU of oxytocin affects gaze behavior for 32 adult males with autism and 34 controls in a real-time interaction with a researcher. This interactive paradigm bypasses many of the limitations encountered with conventional static or computer-based stimuli. Eye movements are recorded using eye tracking, providing an objective measurement of looking patterns. The measure is shown to be sensitive to the reduced eye contact commonly reported in autism, with the autism group spending less time looking to the eye region of the face than controls. Oxytocin administration selectively enhanced gaze to the eyes in both the autism and control groups (transformed mean eye-fixation difference per second=0.082; 95% CI:0.025-0.14, P=0.006). Within the autism group, oxytocin has the most effect on fixation duration in individuals with impaired levels of eye contact at baseline (Cohen's d=0.86). These findings demonstrate that the potential benefits of oxytocin in autism extend to a real-time interaction, providing evidence of a therapeutic effect in a key aspect of social communication.We are grateful to the Autism Research Trust (ART) for funding the consumable costs of this study. BA was supported by the Wellcome Trust. SBC and BC were supported by the MRC during the period of this work. This study was conducted in association with the NIHR CLAHRC-EoE, and the EU-AIMS IMI. MVL was supported by a postdoctoral fellowship from the British Academy. MH was supported by the Deutsche Forschungsgemeinschaft (DFG, HE 5310/1-1) and the European Neuroscience Network NEUREX.This is the final published version. It first appeared at http://www.nature.com/tp/journal/v5/n2/full/tp2014146a.html

Mudanças físicas e químicas durante a maturação de frutos de amora preta

Blackberry (Rubus L.) is a naturally growing fruit in Anatolia. Consumption of fresh and frozen blackberries has increased in the past few years in Turkey. The aim of this study is to analyze blackberry at three levels of ripeness taking into account some physical and chemical properties (color, dry matter, soluble solids, total sugar, titratable acidity, pH, total phenolics, total anthocyanin, and minerals) in order to understand this behavior during the ripening process. Blackberry fruits were harvested at green, red and ripe (mature) stages. The determination of fruit maturity was based on fruit surface color. The dry matter, total phenolics and Hunter L, b values decreased but soluble solids, total sugar and total anthocyanins increased with maturity. In the early fruit ripening stages, pH decreased, titratable acidity and Hunter a value increased while in the later stages, pH increased, titratable acidity and Hunter a value decreased considerably. Analysis of variance revealed (P < 0.01) differences in these parameters based on ripeness stages. No remarkable changes in potassium, calcium, zinc and manganese concentrations occured during the development of fruits. Differences were observed for magnesium (P < 0.01), iron (P < 0.01) and copper (P < 0.05) during ripening of blackberry.Amora preta (blackberry, Rubus L.) é uma fruta que cresce naturalmente na península de Anatolia. O consumo de suas frutas frescas ou congeladas aumentou nos últimos anos na Turquia. Este estudo teve por objetivo analisar amoras pretas colhidas em três níveis de maturação, levando em conta propriedades físicas e químicas das frutas (cor, matéria seca, sólidos solúveis, açúcar total, acidez titulável, pH, fenóis totais, antocianina total e sais minerais) para melhor compreender o processo de maturação. As frutas foram colhidas nos estágios verde, vermelho e maduro. A determinação do estágio maduro foi baseada na cor da superfície das frutas. A materia seca, os fenóis totais e os valores de Hunter L, b diminuiram mas os sólidos solúveis, açúcares totais e total de antocianina decresceram em função do nível de maturação. Nos estágios iniciais de maturação, o pH decresceu, a acidez titulável e o valor a de Hunter aumentaram enquanto nos estágios posteriores o pH aumentou, a acidez titulável e o valor a de Hunter decresceram consideravelmente. A análise de variância revelou diferenças nestes parâmetros (P < 0,01), baseada nos estágios de maturação. Não houve mudanças marcantes nos conteúdos de potássio, calico e magnésio durante o desenvolvimento dos frutos. Diferenças foram obsevadas para magnésio (P < 0,01), ferro (P < 0,01) e cobre (P < 0,05) durante a maturação das amoras pretas

Partial purification and characterization of alkaline proteases from the Black Sea anchovy (Engraulis encrasicholus) digestive tract

Alkaline proteases from the digestive tract of anchovy were partially purified by ammonium sulfate fractionation, dialysis and Sephadex G-75 gel filtration. The purification fold and yield were 6.23 and 4.49%, respectively. The optimum activities of partially purified alkaline proteases were observed at 60°C and at pH 11.0. The alkaline proteases were stable within the temperature range of 40 to 50°C and pH range of 9.0 to 11.0. They were inhibited by the serine-protease inhibitor phenylmethylsulfonyl fluoride (PMSF) and trypsin specific inhibitor benzamidine, but were not inhibited by the β-mercaptoethanol. The enzymes were slightly activated by metal ions such as Na+ and Ba2+ and inhibited by Cu2+, Zn2+, K+ and Mn2+ at different degrees. The molecular weight of the partially purified enzyme was 24 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).Key words: Alkaline proteases, Engraulis encrasicholus, purification, characterization, digestive tract

Teachers’ Record Keeping as Related to Teachers Job Performance in Cross River State Secondary Schools, Nigeria

This research investigated the influence of principal’s inspection of teachers’ record keeping strategy on teachers’ job performance in Cross River State, Nigeria. Subjects involved six hundred and sixty (660) teachers and three thousand, three hundred senior secondary school students which were randomly selected from two hundred and thirty two (232) secondary schools in Cross River State. Data was collected with Principals’ Instructional Supervisory Strategies Questionnaire (PISSQ) and Teachers’ Job Performance Scale Questionnaire (TJPSQ). The result of analysis utilizing one-way analysis of variance (ANOVA) indicated that principal’s inspection of record keeping strategy significantly influenced teachers’ job performance. It is recommended that regular supervision which must include teachers’ record keeping strategy be regularly organized by government to enhance teachers’ job performance