日本冲绳本岛临海民居风景防护林的构建及对中国新民居建设的启示

为加快推进中国农村新民居建设,完善相关配套建设措施,笔者借鉴日本在防灾减灾理论和方法方面处于世界前列,以法律的形式保证规划先行的经验,通过对冲绳本岛相关历史资料分析、民意调查和实地调查,以及福木起源的追溯,福木数量和防护林密度的测算等,论证了福木风景防护林映衬红瓦木造建筑为冲绳典型集落(即村庄、村落)特征.风景防护林的构建源自于村民抵御自然灾害的本能和政府保一方平安的责任意识,最后发展为保护村民生活环境、保障社会安定的基础.同时防护林使冲绳自然环境更显生态美观,促进了旅游业的兴旺,旅游已成为冲绳的支柱产业.     

Nonlinear regression modeling via regularized radial basis function networks

The problem of constructing nonlinear regression models is investigated to analyze data with complex structure. We introduce radial basis functions with hyperparameter that adjusts the amount of overlapping basis functions and adopts the information of the input and response variables. By using the radial basis functions, we construct nonlinear regression models with help of the technique of regularization. Crucial issues in the model building process are the choices of a hyperparameter, the number of basis functions and a smoothing parameter. We present information-theoretic criteria for evaluating statistical models under model misspecification both for distributional and structural assumptions. We use real data examples and Monte Carlo simulations to investigate the properties of the proposed nonlinear regression modeling techniques. The simulation results show that our nonlinear modeling performs well in various situations, and clear improvements are obtained for the use of the hyperparameter in the basis functions.     

Government Partisanship and Human Well-Being

This paper shows that the partisan composition of government is strongly related to the well-being of citizens, measured by the reported level of life satisfaction and suicide rates in industrial countries. Our analysis, using survey data of 14 nations between 1980 and 2002, shows that the presence of left-leaning parties in government is associated with an increase the level of individual life satisfaction. The relationship holds true even after controlling for the effects of macroeconomic variables such as gross domestic product, unemployment rates and government welfare policies. Our panel data analysis of 21 nations between 1980 and 2004 also shows that suicide rates decrease when a country experiences a shift to more left-leaning government. The increased presence of right-wing parties in government has a negligible effect on suicide rates.     

Fate of a mutant emerging at the initial stage of evolution

A simple system was constructed and used in the experimental elucidation of the fate of a mutant emerging in a population. ThreeEscherichia coli strains having the same genetic background except for their glutamine synthetase gene were used as model competitors. The difference in the enzyme gene were introduced by random mutation. Competition between these bacterial strains was carried out and observed in a continuous liquid culture. In most cases, the competitors stably coexist either in a steady state or in an oscillating state. In addition, the competition between the strains was found to be a deterministic process and not a stochastic one. These results showed that an emerging mutant in a population, be it a closely related one to the original members, can attain a state of stable coexistence even in a homogeneous environment. The ability of each of the emerging mutants to maintain its stable coexistence with the original population gives rise to the accumulation of various mutants in a population. Therefore, evolution starts from gradual accumulation of various mutants in the population, which in turn leads to the diversification of the population. As our experimental system is a minimum model for the various competitions in the natural ecosystem, the observed competitive coexistence is proposed to be a general phenomenon in nature.     

The Finite-Sample Performance of White's Test for Heteroskedasticity Under Stochastic Regressors

We study the finite-sample properties of White's test for heteroskedasticity in stochastic regression models where explanatory variables are random and not given. We investigate by simulation the effect of non independence of explanatory variables and error term and heteroskedasticity on White's test. A standard bootstrap method in the computationally convenient form is found to work well with respect to the size and power.     

Clinical trial of treatment with saikokaryukotsuboreito for eugonadal patients with late-inset hypogonadism-related symptoms

The purpose of this study was to evaluate the efficacy and safety of saikokaryukotsuboreito (SKRBT), which is widely used for a variety of clinical conditions, neuropsychiatric disorders, for patients with LOH-related symptoms. Twenty-two eugonadal patients over 40 years of age with LOH-related symptoms were included in this study. SKRBT was given orally to these patients three times daily to a total of 7.5 g/day for more than two months. Laboratory and endocrinological profiles were reviewed, and LOH symptoms were judged by means of several health assessment instruments such as the Aging Males' Symptoms (AMS) scale, Self-rated Depression Scale (SDS), International Prostate Symptom Score (IPSS), and King's Health Questionnaire (KHQ). Total AMS scores and AMS subscores were significantly decreased after the treatment. The KHQ, general health perception and impact on life scores were also significantly decreased, although no significant improvement was observed in other KHQ factors or the SDS score or IPSS. The serum concentrations of testosterone fractions did not change with treatment. Laboratory values did not change, and no adverse effects were identified after treatment. We conclude that SKRBT may be considered for treatment of patients with LOH-related symptoms for eugonadal patients.     

How small can the difference among competitors be for coexistence to occur

Closely related competitors comprising ofEscherichia coli strains having the same metabolic system and differing only with a few bases on the glutamine synthetase gene in the plasmid pKGN were previously shown to coexist in a chemostat. The differences among these closely related competitors can be considered large enough to allow coexistence as the level of enzyme activity is different. To bring the difference among competitors to the slightest possible, the mutation was introduced on the noncoding region of the plasmid pKGN harbored in the wild-type strain (strain W). The new strain, strain W’, carries the plasmid pKGN’ with a 4-base insertion at theHind III site in the polycloning site of pKGN. As the noncoding region is a nucleotide segment that is not translated into amino acids, the relatedness between strains W and W’ is the closest possible from the genetic point of view. Interestingly, though both strains are almost identical, they can coexist stably in a chemostat irrespective of the initial population size. These experimental results suggest that in the natural ecosystem, no matter how akin competitors are, coexistence is not impossible.     

Matrix decomposition in meta-analysis for extraction of adverse event pattern and patient-level safety profile

The purpose of assessing adverse events (AEs) in clinical studies is to evaluate what AE patterns are likely to occur during treatment. In contrast, it is difficult to specify which of these patterns occurs in each patient. To tackle this challenging issue, we constructed a new statistical model including nonnegative matrix factorization by incorporating background knowledge of AE-specific structures such as severity and drug mechanism of action. The model uses a meta-analysis framework for integrating data from multiple clinical studies because insufficient information is derived from a single trial. We demonstrated the proposed method by applying it to real data consisting of three Phase III studies, two mechanisms of action, five anticancer treatments, 3317 patients, 848 AE types, and 99,546 AEs. The extracted typical treatment-specific AE patterns coincided with medical knowledge. We also demonstrated patient-level safety profiles using the data of AEs that were observed by the end of the second cycle.     

Search for Alternatives and Collaboration with Incumbents: Two-Sided Sourcing Behavior in Business Markets*

Sourcing strategies in business markets have been considered separately and the practice of two-sided sourcing behavior—engaging in search for alternative suppliers and collaboration with an incumbent supplier—has not been examined. To fill that gap, we first identify boundary conditions under which the poor performance of an incumbent supplier intensifies an original equipment manufacturer's (OEM) search and collaboration. Then, we examine how an OEM's two-sided sourcing behavior influences one of the critical elements of sourcing performance: the responsiveness of the incumbent supplier. Our proposed hypotheses were tested with data from a national survey of 539 OEM purchasing managers in the Japanese electronics industry. The analysis results indicate three main findings. First, two environmental conditions—pace of technological change and volume uncertainty—have contrasting influences on the link between incumbent supplier performance and an OEM's search and collaboration. While uncertainty from the upstream channel (pace of technological change) enhances an OEM's search and collaboration, uncertainty from the downstream channel (volume uncertainty) lowers an OEM's search and collaboration. Second, an OEM's dependence on its incumbent supplier has differential effects: an OEM reduces search as its dependence on incumbent supplier increases, while it enhances collaboration as its dependence on incumbent supplier increases. Third, while search alone has a negative effect on responsiveness of an incumbent supplier, engaging in two-sided sourcing behavior (i.e., combining search with collaboration) has a positive effect on responsiveness of the incumbent supplier.     

A Simulation Study of White's Test for Heteroskedasticity in Fixed and Stochastic Regression Models

We study the finite-sample properties of White's test for heteroskedasticity in fixed and stochastic regression models. We compare by simulation White and bootstrap methods when the underlying distribution is symmetric as well as asymmetric. The superior performance of the bootstrap method in small samples does not hold when the underlying distribution is asymmetric.