90 research outputs found

    Quantum Theoretical Study on Bond Energy

    Get PDF
    We have already studied the characteristic features of these bonds by idealizing the problem to the electronic structure of fictitious diatomic molecules. In this paper, we carry out the modified calculation in the casse of account of the modified bonding atomic orbitals. We conclude that in the case of λ=O (Heitler-Londn Approximation) the adiabatic potential curve takes minimum value

    Quantum theoretical study on bond angle for single bond between carbon atoms

    Get PDF
    We studied the characteristic features of single, double aud triple bonds between carbon atoms by idealizjng the problem to the electronic structure of fictitious diatomic molecules ≡C-C≡, =C=C= aud -C≡C-, where the "open" bonds of carbon atoms are represented by a suitably hybridized orbitals, associated with free spins. Using this general theory above merhoned, we study bond angle for single bond between carbon atoms. Thus we obtain the following result that in the case of tetrahedral bond angle, the single bond between carbon atoms is most stable

    The Molecular Structure of cis-4-Aza-A-homo-tetrahydro-a-santonin and trans-4- Aza- A- homo- tetrahydro-a-santonin Related to the Lactam Rule

    Get PDF
    Stereochemistry of the titled compounds was determined by X-ray structure analysis. The seven-membered lactam rings of both compounds are in a quasi-chair conformation which agrees with the lactam rule. The mean values of the C-NH-CO-C torsion angles are -6 ° and +5°, respectively, and these values also agree with Klyne\u27s hypothesis

    Comparison of V̇O2 for buoyancy and propulsion during swimming between male and female

    Get PDF
    体脂肪は人体の水中体重を小さくするから, 水泳には体脂肪の多いことが有利な条件となる可能性がある。本研究は水泳の際に浮くために使われるV̇O2と推進のために使われるV̇O2を測定し, 水中体重の大小が実際の水泳にどれほどの影響を与えているかという点について検討したものである。 男女各3名, 計6名の泳者に, 泳速が0.6, 0.8及び1.0m/secのクロール泳を行わせ, V̇O2を測定した。その際腰に錘をつけて水中体重を増加させ, あるいは滑車を介した錘で腰を引き上げるようにして水中体重を減少させ, 各水中体重において上記の測定を行った。V̇O2値を水中体重に対してプロットすることによって得られる回帰直線の勾配から浮くためのV̇O2を, またY切片から安静時V̇O2を差し引くことによって推進のためのV̇O2を求めた。 1 浮くために必要なV̇O2は泳速とは無関係であり, その平均値は男子の方(352±140ml/min)が女子のそれ(186±83ml/min)より有意に大であった。この差は水中体重に大きく依存していて, 単位水中体重当りに換算すると男女の値は接近した(男子: 117±46ml/min, 女子: 91±36ml/min)。 2 推進のために用いられるV̇O2は, 泳速の増加に伴って指数関数的に増大した。その増加率は男子よりも女子の方が大であったが, それは女子の水泳能力が男子のそれより劣ることに関連していると考えられる。 3 総V̇O2に対する推進のためのV̇O2の割合は, 男子よりも女子において大きく, この点女子の水中体重の小さいことは水泳において有利な条件になっている。男子の世界記録に対する女子のそれの比率は, 競泳の場合には競走の場合より大きいが, この差は女子の体脂肪の多いことが水泳では有利に作用していることに由来するものと考えられる。Body fat lessens underwater body weight and may offer an advantage for swimming performance. The present study was undertaken to measure separately V̇O2 for buoyancy and that for propulsion during swimming in the swimming flume and to elucidate the advantage of lower underwater body weight in female. Three male swimmers and three female swimmers participated as the subjects. V̇O2 was measured during free style swimming at a constant speed of 0.6, 0.8 and l.0m/sec.Underwater weight was increased stepwisely by loading an extra-weight around the subject's waist or decreased by suspending a weight which pulls the waist upward via a wire and pulleies. V̇O2 at a given speed depended proportionally on the underwater weight. V̇O2 for propu1sion was estimated by subtracting resting V̇O2 from the intercept on the ordinate, and V̇O2 for buoyancy was calculated from the slope. 1) V̇O2 for buoyancy was independent of swimming speed and the average value for female swimmers was much smaller than that for male swimmers (352±140m1/min for male, 186±83m1/min for female). This difference in V̇O2 for buoyancy depended largely on the difference in underwater weight as the calculated values of V̇O2 for buoyancy per kg of underwater weight revealed much smaller difference between sexes (117±46m1/min for male, 91±36m1/min for female). 2) V̇O2 for propulsion increased exponentially with increasing speed. The increasing rate was larger in female than in male. This is probably because of relative inferiority of swimming ability in the female group in this study. 3) The rate of propulsion V̇O2 to total V̇O2 during swimming was larger in female than in male. This represents the advantage of lower underwater weight in female for swimming. This result offers the probable explanation for the discrepancy which exists in male-female ratio of the world records between swimming and running

    Reproducibility and validity of food group intake in a short food frequency questionnaire for the middle-aged Japanese population

    Get PDF
    Purpose: The purpose of this study was to evaluate the reproducibility and validity of a short food frequency questionnaire (FFQ) for food group intake in Japan, the reproducibility and partial validity of which were previously confirmed for nutrients. Methods: A total of 288 middle-aged healthy volunteers from 11 different areas of Japan provided nonconsecutive 3-day weighed dietary records (DRs) at 3-month intervals over four seasons. We evaluated reproducibility based on the first (FFQ1) and second (FFQ2) questionnaires and their validity against the DRs by comparing the intake of 20 food groups. Spearman’s rank correlation coefficients (SRs) were calculated between energy-adjusted intake from the FFQs and that from the DRs. Results: The intake of 20 food groups estimated from the two FFQs was mostly equivalent. The median energy-adjusted SRs between the FFQ1 and FFQ2 were 0.61 (range 0.38–0.86) for men and 0.66 (0.45–0.84) for women. For validity, the median de-attenuated SRs between DRs and the FFQ1 were 0.51 (0.17–0.76) for men and 0.47 (0.23–0.77) for women. Compared with the DRs, the proportion of cross-classification into exact plus adjacent quintiles with the FFQ1 ranged from 58 to 86% in men and from 57 to 86% in women. According to the robust Z scores and the Bland–Altman plot graphs, the underestimation errors in the FFQ1 tended to be greater in individuals with high mean levels of consumption for meat for men and for other vegetables for both men and women. Conclusion: The FFQ demonstrated high reproducibility and reasonable validity for food group intake. This questionnaire is short and remains appropriate for identifying associations between diet and health/disease among adults in Japan

    Comparison of weighed food record procedures for the reference methods in two validation studies of food frequency questionnaires

    Get PDF
    Background: Although open-ended dietary assessment methods, such as weighed food records (WFRs), are generally considered to be comparable, differences between procedures may influence outcome when WFRs are conducted independently. In this paper, we assess the procedures of WFRs in two studies to describe their dietary assessment procedures and compare the subsequent outcomes. Methods: WFRs of 12 days (3 days for four seasons) were conducted as reference methods for intake data, in accordance with the study protocol, among a subsample of participants of two large cohort studies. We compared the WFR procedures descriptively. We also compared some dietary intake variables, such as the frequency of foods and dishes and contributing foods, to determine whether there were differences in the portion size distribution and intra- and inter-individual variation in nutrient intakes caused by the difference in procedures. Results: General procedures of the dietary records were conducted in accordance with the National Health and Nutrition Survey and were the same for both studies. Differences were seen in 1) selection of multiple days (non-consecutive days versus consecutive days); and 2) survey sheet recording method (individual versus family participation). However, the foods contributing to intake of energy and selected nutrients, the portion size distribution, and intra- and inter-individual variation in nutrient intakes were similar between the two studies. Conclusion: Our comparison of WFR procedures in two independent studies revealed several differences. Notwithstanding these procedural differences, however, the subsequent outcomes were similar

    Undergraduate educational environment, perceived preparedness for postgraduate clinical training, and pass rate on the National Medical Licensure Examination in Japan

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>We investigated the views of newly graduating physicians on their preparedness for postgraduate clinical training, and evaluated the relationship of preparedness with the educational environment and the pass rate on the National Medical Licensure Examination (NMLE).</p> <p>Methods</p> <p>Data were obtained from 2429 PGY-1 physicians-in-training (response rate, 36%) using a mailed cross-sectional survey. The Dundee Ready Education Environment Measure (DREEM) inventory was used to assess the learning environment at 80 Japanese medical schools. Preparedness was assessed based on 6 clinical areas related to the Association of American Medical Colleges Graduation Questionnaire.</p> <p>Results</p> <p>Only 17% of the physicians-in-training felt prepared in the area of general clinical skills, 29% in basic knowledge of diagnosis and management of common conditions, 48% in communication skills, 19% in skills associated with evidence-based medicine, 54% in professionalism, and 37% in basic skills required for a physical examination. There were substantial differences among the medical schools in the perceived preparedness of their graduates. Significant positive correlations were found between preparedness for all clinical areas and a better educational environment (all p < 0.01), but there were no significant associations between the pass rate on the NMLE and perceived preparedness for any clinical area, as well as pass rate and educational environment (all p > 0.05).</p> <p>Conclusion</p> <p>Different educational environments among universities may be partly responsible for the differences in perceived preparedness of medical students for postgraduate clinical training. This study also highlights the poor correlation between self-assessed preparedness for practice and the NMLE.</p

    Body mass index and colorectal cancer risk : A Mendelian randomization study

    Get PDF
    Traditional observational studies have reported a positive association between higher body mass index (BMI) and the risk of colorectal cancer (CRC). However, evidence from other approaches to pursue the causal relationship between BMI and CRC is sparse. A two-sample Mendelian randomization (MR) study was undertaken using 68 single nucleotide polymorphisms (SNPs) from the Japanese genome-wide association study (GWAS) and 654 SNPs from the GWAS catalogue for BMI as sets of instrumental variables. For the analysis of SNP-BMI associations, we undertook a meta-analysis with 36 303 participants in the Japanese Consortium of Genetic Epidemiology studies (J-CGE), comprising normal populations. For the analysis of SNP-CRC associations, we utilized 7636 CRC cases and 37 141 controls from five studies in Japan, and undertook a meta-analysis. Mendelian randomization analysis of inverse-variance weighted method indicated that a one-unit (kg/m2) increase in genetically predicted BMI was associated with an odds ratio of 1.13 (95% confidence interval, 1.06-1.20; P value <.001) for CRC using the set of 68 SNPs, and an odds ratio of 1.07 (1.03-1.11, 0.001) for CRC using the set of 654 SNPs. Sensitivity analyses robustly showed increased odds ratios for CRC for every one-unit increase in genetically predicted BMI. Our MR analyses strongly support the evidence that higher BMI influences the risk of CRC. Although Asians are generally leaner than Europeans and North Americans, avoiding higher BMI seems to be important for the prevention of CRC in Asian populations
    corecore