Hydrogen-atom Attack on Phenol and Toluene is \u3cem\u3eortho\u3c/em\u3e-directed

The reaction of H + phenol and H/D + toluene has been studied in a supersonic expansion after electric discharge. The (1 + 1′) resonance-enhanced multiphoton ionization (REMPI) spectra of the reaction products, at m/z = parent + 1, or parent + 2 amu, were measured by scanning the first (resonance) laser. The resulting spectra are highly structured. Ionization energies were measured by scanning the second (ionization) laser, while the first laser was tuned to a specific transition. Theoretical calculations, benchmarked to the well-studied H + benzene → cyclohexadienyl radical reaction, were performed. The spectrum arising from the reaction of H + phenol is attributed solely to the ortho-hydroxy-cyclohexadienyl radical, which was found in two conformers (syn and anti). Similarly, the reaction of H/D + toluene formed solely the ortho isomer. The preference for the ortho isomer at 100–200 K in the molecular beam is attributed to kinetic, not thermodynamic effects, caused by an entrance channel barrier that is ∼5 kJ mol−1 lower for ortho than for other isomers. Based on these results, we predict that the reaction of H + phenol and H + toluene should still favour the ortho isomer under elevated temperature conditions in the early stages of combustion (200–400 °C)

Vertical Strained Impact Ionization MOSFET (VESIMOS) Technology Approach for Based Biosensor Applications using its Behavioral Model

This paper gives an overview about uniqueness characteristics of Vertical Strained Impact Ionization MOSFET (VESIMOS) technology act as bio-sensing devices. There are three proposed devices used VESIMOS technology which are Single Channel VESIMOS (SC-VESIMOS), Dual Channel (DC-VESIMOS), VESIMOS Incorporating Dielectric Pocket (VESIMOS-DP) are probably can become feasible candidates as biosensor devices. The selected devices from three structures was further analyzed for its behavioral model. The extracted parameter from the device simulations was used to design the circuitry model to represent the characteristic and behavior of the selected devices in circuit implementation. The best characteristic of the device shown by DC-VESIMOS and selected for further analysis. The behavioral model or equivalent circuit model of DC-VESIMOS used PSPICE circuit simulator. Main prerequisite of biosensor device are high sensitivity, faster response, and high reliability which represented by the VESIMOS structures. Low subthreshold swings present the sensitivity of the devices shown by DC-VESIMOS are 11.48 mV/dec and 10.53 mV/dec from TCAD and PSPICE results respectively

汉字笔顺教学描述研究 以2013/2014学年坤甸市以马内利中专二校十年级学生为例

摘要：汉字，是中华民族五千年文化的积淀，具有形、声、意的特点。很多非汉字文化圈的学生学习汉语都感觉十分困难，特别是在汉字书写 方面，更加难以把握汉字的笔画以及笔顺，容易造成汉字书写偏误。为了 提高以马内利中专2校学生的汉字书写能力以及寻求汉字书写教学的方法， 笔者通过问卷调查和实地调查访问的方式对以马内利中专2校生进行调查 研究，通过对以马内利2校学生的汉字笔画笔顺掌握情况和书写偏误进行 分析， 发现了问题所在，并提出了相关建议。 关键词： 汉字笔顺 ； 汉字教学 ； 汉字书写 Abstract : The Chinese character, which is a great cultural heritage of the five-thousand-years Chinese nation, is perfectly featured with different forms,pronunciations and meanings. However, most students who are not from sinosphere find it hard to learn Chinese, especially in handwriting which includes the character strokes and orders and easily causes clerical errors. Therefore, to improve student's handwriting of Chinese characters in SMK Immanuel 2 and seek the related education methods, I made a questionnaire survey and a field survey there to learn about the student's knowledge about strokes and orders of Chinese characters and the mistakes they made. Finally, I found the crux of the matter and proposed the related suggestions accordings to the result of the surveys

Delayed school progression and mental health problems in adolescence:A population-based study in 10,803 adolescents

Background Accumulating evidence suggests that several adult mental disorders, particularly psychoses, are preceded by impairments in cognitive function, reflected in scholastic underachievement. This study investigates the association between scholastic underachievement and general mental health problems in adolescence, using delay in school progression as a marker of poor scholastic performance.MethodCross-sectional secondary school survey comprising 10,803 adolescents. Participants completed the Strengths and Difficulties Questionnaire (SDQ) to assess mental health problems. The association of delayed school progression with the SDQ was investigated using logistic regression with SDQ as outcome and delayed school progression as primary exposure of interest while adjusting for socio-demographic characteristics, adverse life events, school-related factors, risk taking behaviour, healthy lifestyle and physical health.ResultsUnadjusted analysis showed an association between delayed school progression and total mental health problems (OR 1.83, 95% CI 1.27 - 2.63) in adolescents. After adjusting for other risk factors (socio-demographic factors and life events) in a logistic regression model the association between delayed school progression en mental health problems was attenuated (OR 1.33, 95% CI 0.86 - 2.05).ConclusionDelayed school progression is associated with general mental health problems in adolescence, but this relationship is heavily confounded by other factors. A causal relationship between impaired cognitive function such as poor scholastic performance and general mental health at adolescence is less likely and delayed school progression may merely be considered an indicator of risk for mental health problems.</p

Immunological detection of alkaline-diaminobenzidine-negative peroxisomes of the nematode Caenorhabditis elegans: Purification and unique pH optima of peroxisomal catalase

We purified catalase-2 of the nematode Caenorhabditis elegans and identified peroxisomes in this organism. The peroxisomes of C. elegans were not detectable by cytochemical staining using 3,3'-diaminobenzidine, a commonly used method depending on the peroxidase activity of peroxisomal catalase at pH 9 in which genuine peroxidases are inactive. The cDNA sequences of C. elegans predict two catalases very similar to each other throughout the molecule, except for the short C-terminal sequence; catalase-2 (500 residues long) carries a peroxisomal targeting signal 1-like sequence (Ser-His-Ile), whereas catalase-1 does not. The catalase purified to near homogeneity from the homogenate of C. elegans cells consisted of a subunit of 57 kDa and was specifically recognized by anti-(catalase-2) serum but not by anti-(catalase-1) serum. Subcellular fractionation and indirect immunoelectron microscopy of the nematode detected catalase-2 inside vesicles judged to be peroxisomes using morphological criteria. The purified enzyme (220 kDa) was tetrameric, similar to many catalases from various sources, but exhibited unique pH optima for catalase (pH 6) and peroxidase (pH 4) activities; the latter value is unusually low and explains why the peroxidase activity was undetectable using the standard alkaline diaminobenzidine- staining method. These results indicate that catalase-2 is peroxisomal and verify that it can be used as a marker enzyme for C. elegans peroxisomes

The role and challenges of cluster randomised trials for global health

Evaluating whether an intervention works when trialled in groups of individuals can pose complex challenges for clinical research. Cluster randomised controlled trials involve the random allocation of groups or clusters of individuals to receive an intervention, and they are commonly used in global health research. In this paper, we describe the potential reasons for the increasing popularity of cluster trials in low-income and middle-income countries. We also draw on key areas of global health research for an assessment of common trial planning practices, and we address their methodological shortcomings and pitfalls. Lastly, we discuss alternative approaches for population-level intervention trials that could be useful for research undertaken in low-income and middle-income countries for situations in which the use of cluster randomisation might not be appropriate