93 research outputs found

    Transformations with improved asymptotic approximations and their accuracy

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    Suppose that a statistic SS is asymptotically distributed as a distribution function G(x)G(x) as some parameter ϵ0\epsilon\to 0. We consider monotone transformations of SS in order to improve the asymptotic approximation. The transformations proposed here preserve monotonicity and give transformed statistics T(S)T(S) whose distribution function is coincident with G(x)G(x) up to the order O(ϵr1)O(\epsilon^{r-1}). It may be observed that the proposed transformations give a significant improvement to approximations. Further, we shall also consider error bounds for the remainder term of an asymptotic expansion for the distribution of T(S)T(S). Finally, some applications of the findings are demonstrated for some test statistics

    Development of a 20-item questionnaire for drinking behavior pattern (DBP-20) toward personalized behavioral approaches for alcohol use disorder

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    Although screening tools are available for alcohol use disorders (AUD), such as the Alcohol Use Disorders Identification Test (AUDIT), these tools do not directly characterize individual drinking behavior for patients with AUD. Therefore, the aim of this study was to develop a new self-report questionnaire to identify the characteristics of drinking behavior patterns in patients with AUD. The study team developed a self-administered 20-item questionnaire for drinking behavior pattern (DBP-20) based on semistructured interviews of patients with AUD. The DBP-20 and AUDIT were administered to 232 patients with AUD and 222 normal drinkers (1 ≤ AUDIT <20) as controls. Exploratory factor analysis of the DBP-20 was conducted for patients with AUD, followed by comparisons of its item and subscale scores between patients with AUD and controls. Correlations of AUDIT with total and subscale scores of the DBP-20 were also analyzed. Receiver operating characteristic (ROC) analyses for the DBP-20 and its subscales were performed to distinguish patients with AUD from controls. Exploratory factor analysis revealed a multidimensional 4-factor model of the DBP-20: coping with negative affect, automaticity, enhancement, and social use. Significant differences in DBP-20 total and subscale scores were observed for patients with AUD versus controls for all factors, except the social use subscale. Both the coping with negative affect and automaticity subscale scores as well as total DBP-20 scores were highly correlated with AUDIT scores. Total DBP-20 scores showed the greatest sensitivity, negative predictive value, and area under the ROC curve to distinguish patients with AUD from normal drinkers. Drinking as a means of coping with negative affect and automaticity may be specific for patients with AUD. DBP-20 may help patients with AUD to be aware of their own targeted problematic drinking behaviors and to seek their personalized behavioral approaches in a collaborative relationship with therapists

    Effects of attitudes towards ambiguity on subclinical depression and anxiety in healthy individuals

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    This study aims to examine the effects of multidimensional attitudes towards ambiguity on subclinical depression and anxiety in healthy individuals. Attitudes Towards Ambiguity Scale, consisting of four clusters (enjoyment, anxiety, exclusion, and noninterference), Self-Rating Depression Scale, and State-Trait Anxiety Inventory–trait version were administered to 1019 Japanese volunteers. The result of a regression analysis suggested that the score of Attitudes Towards Ambiguity Scale–enjoyment factor significantly contributed to the Self-Rating Depression Scale score while that of Attitudes Towards Ambiguity Scale–anxiety factor significantly contributed to the State-Trait Anxiety Inventory–trait score. Among attitudes toward ambiguity, enjoyment may have protective effects against subclinical depression whereas anxiety can enhance anxiety-trait in nonclinical individuals

    Attitudes towards Ambiguity in Japanese Healthy Volunteers

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    Multi-dimensional structure of the Attitudes Towards Ambiguity Scale (ATAS: original Japanese version) and its relationship with the Acceptance and Action Questionnaire (AAQ) were investigated. We administered the ATAS and the Japanese version of the AAQ to 1019 Japanese healthy volunteers (513 females and 506 males; age range 18–78 years). Trial of exploratory factor analysis extracted four distinct clusters (Enjoyment; α = .83, Anxiety; α = .75, Exclusion; α = .75, and Noninterference; α = .65) from the ATAS item pool, suggestive of diversity in cognitive/ emotional/ behavioral responses to ambiguity. Confirmative factor analysis showed similar goodness in fit indices between the new four-factor model in the present study and the original five-factor model in our previous study (Nishimura 2007). Considering interpretability by using large number of representative samples with general population in the present study, we adopted the four-factor model. The ATAS Anxiety subscale was negatively correlated with the AAQ willingness subscale (r = −.39, p < .001), while the ATAS Enjoyment subscale was positively correlated with the AAQ Action subscale (r = .40, p < .001). It is thus suggested that one who enjoys ambiguous situations can adopt two distinct attitudes: Excluding ambiguity from active resolution, or not interfering with ambiguity due to good tolerance of this experience, which can lead to positive and flexible commitments in life. In contrast, one who tends to be anxious about ambiguity may be characterized by exclusion-based attitudes due to intolerance of ambiguity, leading to lowered acceptance of their feelings and of the reality of circumstances. Cognitive/emotional attitudes towards ambiguity may affect acceptance of inner experience and active commitment to reality

    Potential of Genomic Selection in Mass Selection Breeding of an Allogamous Crop: An Empirical Study to Increase Yield of Common Buckwheat

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    To evaluate the potential of genomic selection (GS), a selection experiment with GS and phenotypic selection (PS) was performed in an allogamous crop, common buckwheat (Fagopyrum esculentum Moench). To indirectly select for seed yield per unit area, which cannot be measured on a single-plant basis, a selection index was constructed from seven agro-morphological traits measurable on a single plant basis. Over 3 years, we performed two GS and one PS cycles per year for improvement in the selection index. In GS, a prediction model was updated every year on the basis of genotypes of 14,598–50,000 markers and phenotypes. Plants grown from seeds derived from a series of generations of GS and PS populations were evaluated for the traits in the selection index and other yield-related traits. GS resulted in a 20.9% increase and PS in a 15.0% increase in the selection index in comparison with the initial population. Although the level of linkage disequilibrium in the breeding population was low, the target trait was improved with GS. Traits with higher weights in the selection index were improved more than those with lower weights, especially when prediction accuracy was high. No trait changed in an unintended direction in either GS or PS. The accuracy of genomic prediction models built in the first cycle decreased in the later cycles because the genetic bottleneck through the selection cycles changed linkage disequilibrium patterns in the breeding population. The present study emphasizes the importance of updating models in GS and demonstrates the potential of GS in mass selection of allogamous crop species, and provided a pilot example of successful application of GS to plant breeding

    Label-free single-particle imaging of the influenza virus by objective-type total internal reflection dark-field microscopy.

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    Here we report label-free optical imaging of single particles of the influenza virus attached on a glass surface with a simple objective-type total internal reflection dark-field microscopy (TIRDFM). The capability of TIRDFM for the imaging of single viral particles was confirmed from fine correlation of the TIRDFM images with fluorescent immunostaining image and scanning electron microscopy image. The density of scattering spots in the TIRDFM images showed a good linearity against the virus concentration, giving the limit of detection as 1.2×10(4) plaque-forming units per milliliter. Our label-free optical imaging method does require neither elaborated sample preparation nor complex optical systems, offering a good platform for rapid and sensitive counting of viral particles
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