Hoop Conjecture and Black Holes on a Brane

The initial data of gravity for a cylindrical matter distribution confined to a brane are studied in the framework of the single-brane Randall-Sundrum scenario. In this scenario, the 5-dimensional nature of gravity appears in the short-range gravitational interaction. We find that a sufficiently thin configuration of matter leads to the formation of a marginal surface, even if the configuration is infinitely long. This implies that the hoop conjecture proposed by Thorne does not hold on the brane: Even if a mass $M$ does not become compacted into a region whose circumference ${\cal C}$ in every direction satisfies ${\cal C}> 4\pi GM$, black holes with horizons can form in the Randall-Sundrum scenario.Comment: 7 pages, 1 figure, To be published in Progress of Theoretical Physics Supplement No. 148 "Brane World: New Perspective in Cosmology

Building of minimum air temperature forecast system using the Internet -Design of the forecast website-

　The purpose of this study is to build a forecast system for predicting at minimum air temperature in the next morning from the meteorological data, such as air temperature, humidity, and the amount of solar radiation, in a field in the evening on the previous day. The meteorological data are sent to a relay server, and then, transferred to a PC in our laboratory of Okayama University by executing the computer program to import the data which are used to calculate the predicted values of minimum air temperature. The predicted minimum air temperatures are released for the farmers on the website in the server of Okayama University. The website is also created by our laboratory. As a result, the predicted minimum air temperatures agreed with the measured ones

Method for predicting minimum air temperature in the next morning using local meteorological observation data - Improvement on minimum air temperature forecasting system utilizing the Internet -

We have developed a minimum air temperature forecasting system using local meteorological observation data in order to prevent or mitigate the frost damage. In this paper, the correlation between the meteorological factors and the decrease in air temperature during the night was shown. Then minimum air temperature was predicted by the multiple regression equation that uses air temperature and humidity at 18:00 as explanatory variables. As the result, the root mean square error (RMSE) was 2.8°C. When the difference of air temperature between 17:00 and 18:00 was used for the prediction instead of humidity, the RMSE was 3.5°C. Next, the prediction was carried out only in clear nights, then the equation that use air temperature and humidity at 18:00 showed that the RMSE was 1.3°C. Although the predictive accuracy of the equations for clear nights is low on cloudy or rainy nights, we can forecast safely on frosty nights by using those equations in combination with the equations for all nights

Estrogenic Activities of Fatty Acids and a Sterol Isolated from Royal Jelly

We have previously reported that royal jelly (RJ) from honeybees (Apis mellifera) has weak estrogenic activity mediated by interaction with estrogen receptors that leads to changes in gene expression and cell proliferation. In this study, we isolated four compounds from RJ that exhibit estrogenic activity as evaluated by a ligand-binding assay for the estrogen receptor (ER) β. These compounds were identified as 10-hydroxy-trans-2-decenoic acid, 10-hydroxydecanoic acid, trans-2-decenoic acid and 24-methylenecholesterol. All these compounds inhibited binding of 17β-estradiol to ERβ, although more weakly than diethylstilbestrol or phytoestrogens. However, these compounds had little or no effect on the binding of 17β-estradiol to ERα. Expression assays suggested that these compounds activated ER, as evidenced by enhanced transcription of a reporter gene containing an estrogen-responsive element. Treatment of MCF-7 cells with these compounds enhanced their proliferation, but concomitant treatment with tamoxifen blocked this effect. Exposure of immature rats to these compounds by subcutaneous injection induced mild hypertrophy of the luminal epithelium of the uterus, but was not associated with an increase in uterine weight. These findings provide evidence that these compounds contribute to the estrogenic effect of RJ

Preferable Forms of Relaxation for Health Promotion, and the Association between Recreational Activities and Self-perceived Health

Little research has been done on the association between relaxation and health. In the present study, by conducting a nationwide cross-sectional survey, we aimed to obtain scientific data on the preferable forms of relaxation for health promotion, and to clarify the associations between specific recreational activities and self-perceived mental and physical health. We selected 4,000 households by stratified random sampling from across Japan in November 2009 and used the interview method to collect data (number of subjects:2,206). The questionnaire contained items on sleep, recreation status, recreational activities, and self-perceived mental and physical health status. We obtained responses from 1,224 adults (response rate:55.5%). Insufficient rest from sleep, short sleep duration (＜6h/day), ineffective use of free time, and less free time used for activities other than rest showed independent positive associations with poor mental and physical health. The results of the logistic regression analyses showed significantly low adjusted odds ratios with regard to the status of poor mental and physical health for outings/walking among men (0.33 [95% confidence interval;0.16-0.68] and 0.49 [0.26-0.90], respectively), and for community activities among women (0.19 [0.04-0.79] and 0.27 [0.09-0.77], respectively). Relaxation for the promotion of health should include both passive relaxation (rest) and active relaxation (recreation). In addition, ensuring sufficient sleep duration is important for passive relaxation, and engaging in outings/walking for men and community activities for women are important for active relaxation

Fast Ad-Hoc Search Algorithm for Personalized PageRank

Personalized PageRank (PPR) is a typical similarity metric between nodes in a graph, and node searches based on PPR are widely used. In many applications, graphs change dynamically, and in such cases, it is desirable to perform ad hoc searches based on PPR. An ad hoc search involves performing searches by varying the search parameters or graphs. However, as the size of a graph increases, the computation cost of performing an ad hoc search can become excessive. In this paper, we propose a method called Castanet that offers fast ad hoc searches of PPR. The proposed method features (1) iterative estimation of the upper and lower bounds of PPR scores, and (2) dynamic pruning of nodes that are not needed to obtain a search result. Experiments confirm that the proposed method does offer faster ad hoc PPR searches than existing methods

A Research on the Effect of a Teacher Training Program for Freshmen,“The Visit to Their Old High School”

岡山大学は全学の教職課程を担う「教師教育開発センター」を平成22年度に創設し、学部の枠を超えた教員養成教育の質保証に取り組んでいる。教育実習事前事後指導や教育実習ならびに教職実践演習（平成25年度から実施）等を中心とする「全学教職コア・カリキュラム」の企画・運営だけではなく、これらの科目の教育成果とその課題を検証し、FD的視点に基づくカリキュラム開発と改善とを進めている。「母校訪問」とは、教育学部以外の学生（文学部、法学部、経済学部、理学部、工学部、環境理工学部、農学部、マッチングプログラムコース）のうち、改正後の教育職員免許法が適用される平成22 年度以降入学生（現１、２年生）を対象に、センターが独自に開発した１年次生対象のプログラムである。本稿ではその成果と課題の検証を通して、いわゆる「開放制」と「大学における教員養成」の原則に基づいた教員養成教育の可能性を検討する

Photopumped laser oscillation and charge-injected luminescence from organic semiconductor single crystals of a thiophene/phenylene co-oligomer

This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in APPLIED PHYSICS LETTERS. 87:221113(2005) and may be found at https://doi.org/10.1063/1.2138361 .ArticleAPPLIED PHYSICS LETTERS. 87:221113(2005)journal articl

Parthenogenetic mosaicism: generation via second polar body retention and unmasking of a likely causative PER2 variant for hypersomnia

Background Parthenogenetic mosaicism is an extremely rare condition identified only in five subjects to date. The previous studies indicate that this condition is mediated by parthenogenetic activation and is free from a specific phenotype ascribed to unmaking of a maternally inherited recessive variant in the parthenogenetic cell lineage. Results We examined a 28-year-old Japanese 46,XX female with Silver-Russell syndrome and idiopathic hypersomnia. The results revealed (1) predominance of maternally derived alleles for all the differentially methylated regions examined; (2) no disease-related copy-number variant; (3) two types of regions for all chromosomes, i.e., four BAF (B-allele frequency) band regions with single major microsatellite peaks of maternal origin and single minor microsatellite peaks of non-maternal (paternal) origin, and six BAF band regions with single major microsatellite peaks of maternal origin and two minor microsatellite peaks of maternal and non-maternal (paternal) origin; (4) an unmasked extremely rare PER2 variant (c.1403G>A:p.(Arg468Gln)) with high predicted pathogenicity; (5) mildly affected local structure with altered hydrogen bonds of the p.Arg468Gln-PER2 protein; and (6) nucleus-dominant subcellular distribution of the p.Arg468Gln-PER2 protein. Conclusions The above findings imply that the second polar body retention occurred around fertilization, resulting in the generation of the parthenogenetic cell lineage by endoreplication of a female pronucleus and the normal cell lineage by fusion of male and female pronuclei, and that the homozygous PER2 variant in the parthenogenetic cells is the likely causative factor for idiopathic hypersomnia