Coincidence analysis to search for inspiraling compact binaries using TAMA300 and LISM data

Japanese laser interferometric gravitational wave detectors, TAMA300 and LISM, performed a coincident observation during 2001. We perform a coincidence analysis to search for inspiraling compact binaries. The length of data used for the coincidence analysis is 275 hours when both TAMA300 and LISM detectors are operated simultaneously. TAMA300 and LISM data are analyzed by matched filtering, and candidates for gravitational wave events are obtained. If there is a true gravitational wave signal, it should appear in both data of detectors with consistent waveforms characterized by masses of stars, amplitude of the signal, the coalescence time and so on. We introduce a set of coincidence conditions of the parameters, and search for coincident events. This procedure reduces the number of fake events considerably, by a factor $\sim 10^{-4}$ compared with the number of fake events in single detector analysis. We find that the number of events after imposing the coincidence conditions is consistent with the number of accidental coincidences produced purely by noise. We thus find no evidence of gravitational wave signals. We obtain an upper limit of 0.046 /hours (CL $= 90$) to the Galactic event rate within 1kpc from the Earth. The method used in this paper can be applied straightforwardly to the case of coincidence observations with more than two detectors with arbitrary arm directions.Comment: 28 pages, 17 figures, Replaced with the version to be published in Physical Review

Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004

We analyze the data of TAMA300 detector to search for gravitational waves from inspiraling compact star binaries with masses of the component stars in the range 1-3Msolar. In this analysis, 2705 hours of data, taken during the years 2000-2004, are used for the event search. We combine the results of different observation runs, and obtained a single upper limit on the rate of the coalescence of compact binaries in our Galaxy of 20 per year at a 90% confidence level. In this upper limit, the effect of various systematic errors such like the uncertainty of the background estimation and the calibration of the detector's sensitivity are included.Comment: 8 pages, 4 Postscript figures, uses revtex4.sty The author list was correcte

地域包括ケアシステムにおける訪問看護ステーションの経営状況と事業所特性及び地域特性，経営管理との関連―全国と群馬県の比較―

目的：全国及び群馬県の訪問看護ステーション（以下，ST）の経営状況と事業所特性及び地域特性，経営管理との関連を明らかにし，比較検討する． 方法：全国2,000人及び群馬県163人のST管理者を対象とし，自記式質問紙調査を実施した．有効回答は全国473人，群馬県55人で，経営状況と各項目との関連はχ2検定及びKruskal-Wallis検定を，さらに経営状況を目的変数とするロジスティック回帰分析を行った． 結果：全国では，看護師常勤・看護師非常勤・事務職員非常勤の従業者数，1人1日平均訪問回数，北海道・東北地域，収支のモニタリングが黒字に関連していた．群馬県では関連がみられず，全国に比して赤字のST割合が多く，経営管理の得点が低かった． 結論：経営状況の改善には，ST規模の拡大やST管理者の収支のモニタリングに焦点を当てた行動の有効性が示唆された．群馬県では，経営管理に関する分析の強化が必要である．Objectives: The financial status of home-visit nursing stations (STs) was analyzed in relation to business office characteristics, local community characteristics and business management, and the results between Gunma Prefecture and all prefectures in Japan were compared. Methods: A self-administered questionnaire survey was completed by 163 ST managers in Gunma Prefecture and 2000 ST managers from all over Japan. Valid responses were collected from 55 managers from Gunma Prefecture and 473 managers from all over Japan. The association between management status with each variable was analyzed by the chisquare test and Kruskal-Wallis test. In addition, logistic regression analysis was carried out with the status of management as the dependent variable. Results: For STs all prefectures in Japan, profitable business (black-ink balance) was associated with the number of employees (full-time nurses, part-time nurses and part-time clerical staff), the mean number of care receiver homes visited daily by each nurse, the district (Hokkaido/Tohoku) and revenue/expenditure balance monitoring. In Gunma Prefecture, the percentage of red-ink operation STs was higher and the score for business management was lower than in all prefectures in Japan. Conclusions: These results suggest that management actions focusing on expansion of the scale of STs and on revenue/ expenditure balance monitoring by ST managers are effective in improving the status of management. In Gunma Prefecture, reinforcement of how to analyze business management is needed.原

Daytime nap and nighttime breastfeeding are associated with toddlers\u27 nighttime sleep

The purpose of the present study is to examine the association between toddlers\u27 sleep arrangements and their nighttime sleep duration and other sleep variables. For this investigation, we performed a study in which child activity and sleep levels were recorded using actigraphy. The parents of 1.5-year-old toddlers (n = 106) were asked to attach an actigraphy unit to their child’s waist with an adjustable elastic belt and complete a sleep diary for 7 consecutive days. Questionnaires were used to assess the sleep arrangements of the toddlers. There was a significant negative correlation between nap duration and nighttime sleep duration, suggesting that longer nap sleep induces shorter nighttime sleep duration. Among the sleep arrangements, such as nighttime breastfeeding or co-sleeping, only nighttime breastfeeding predicted shorter nighttime sleep duration. Our findings indicate that shorter naps induce a longer nighttime sleep in 1.5-year-old toddlers while nighttime breastfeeding decreases their nighttime sleep duration

Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses

We present data-analysis schemes and results of observations with the TAMA300 gravitational-wave detector, targeting burst signals from stellar-core collapse events. In analyses for burst gravitational waves, the detection and fake-reduction schemes are different from well-investigated ones for a chirp-wave analysis, because precise waveform templates are not available. We used an excess-power filter for the extraction of gravitational-wave candidates, and developed two methods for the reduction of fake events caused by non-stationary noises of the detector. These analysis schemes were applied to real data from the TAMA300 interferometric gravitational wave detector. As a result, fake events were reduced by a factor of about 1000 in the best cases. The resultant event candidates were interpreted from an astronomical viewpoint. We set an upper limit of 2.2x10^3 events/sec on the burst gravitational-wave event rate in our Galaxy with a confidence level of 90%. This work sets a milestone and prospects on the search for burst gravitational waves, by establishing an analysis scheme for the observation data from an interferometric gravitational wave detector

Sleep maturation influences cognitive development of preterm toddlers

Our recent study on full-term toddlers demonstrated that daytime nap properties affect the distribution ratio between nap and nighttime sleep duration in total sleep time but does not affect the overall total amount of daily sleep time. However, there is still no clear scientific consensus as to whether the ratio between naps and nighttime sleep or just daily total sleep duration itself is more important for healthy child development. In the current study, to gain an answer to this question, we examined the relationship between the sleep properties and the cognitive development of toddlers born prematurely using actigraphy and the Kyoto scale of psychological development (KSPD) test. 101 premature toddlers of approximately 1.5 years of age were recruited for the study. Actigraphy units were attached to their waist with an adjustable elastic belt for 7 consecutive days and a child sleep diary was completed by their parents. In the study, we found no significant correlation between either nap or nighttime sleep duration and cognitive development of the preterm toddlers. In contrast, we found that stable daily wake time was significantly associated with better cognitive development, suggesting that sleep regulation may contribute to the brain maturation of preterm toddlers

Preterm toddlers have low nighttime sleep quality and high daytime activity.

A number of studies have been made on the sleep characteristics of children born preterm in an attempt to develop methods to address the sleep problems commonly observed among such children. However, the reported sleep characteristics from these studies vary depending on the observation methods used, i.e., actigraphy, polysomnography and questionnaire. In the current study, to obtain reliable data on the sleep characteristics of preterm-born children, we investigated the difference in sleep properties between 97 preterm and 97 term toddlers of approximately 1.5 years of age using actigraphy. Actigraphy units were attached to the toddlers’ waists with an adjustable elastic belt for 7 consecutive days, and a child sleep diary was completed by their parents. In the study, we found that preterm toddlers had more nocturnal awakenings and more daytime activity, suggesting that preterm-born children may have a different process of sleep development in their early development