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31.
The B-matrix method, which systematically analyses the dynamic response of non-symmetric rigid bodies, such as golf putters, is described. The three-dimensional translational and rotational accelerations of the putter face are represented by linear equations of input forces and moments represented in matrix form. The elements of the 6 × 6 B-matrix physically represent the acceleration intensity factors. This method is applied to the analysis of the putter face control mechanism. The input forces and moments are obtained by the inverse dynamics method, whilst special attention is paid to the putter face rotation, i.e. the angular acceleration around the axis of the shaft, $ \dot{w}_{ox} . $ The contribution of input forces and moments on $ \dot{w}_{ox} $ is discussed quantitatively. The results demonstrate that $ \dot{w}_{ox} $ is present even if the input force and moment are applied perpendicularly to the shaft. A cancelling mechanism to correct this motion is discussed based on the B-matrix method.  相似文献   
32.

Objective

The ideal medication for the treatment of acid-related diseases, e.g., peptic ulcers, stress-related gastric bleeding, functional dyspepsia, and gastroesophageal reflux disease, should have a rapid onset of action to promote hemostasis and relieve the symptoms. The aim of our study was to investigate the inhibitory effects on gastric acid secretion of a single oral administration of a proton pump inhibitor, omeprazole 20 mg, and an H2-receptor antagonist, roxatidine 75 mg.

Methods

Ten Helicobacter pylori-negative male subjects participated in this randomized, two-way crossover study. Intragastric pH was monitored continuously for 6 h after single oral administration of omeprazole 20 mg and roxatidine 75 mg. Each administration was separated by a 7-d washout period.

Results

During the 6-h study period, the average pH after administration of roxatidine was higher than that after administration of omeprazole (median: 4.45 vs. 2.65; P=0.0367). Also during the 6-h study period, a longer duration of maintenance at pH above 2, 5, and 6 was observed after administration of roxatidine 75 mg than after administration of omeprazole 20 mg (median: 90.6% vs. 55.2%, P=0.0284; 43.7% vs. 10.6%, P=0.0125; 40.3% vs. 3.3%, P=0.0125; respectively).

Conclusions

In Helicobacter pylori-negative healthy male subjects, oral administration of roxatidine 75 mg increased the intragastric pH more rapidly than that of omeprazole 20 mg.  相似文献   
33.
Abstract

The aim of this study was to investigate the effects of sleep deprivation on autonomic and endocrine functions during the day and on exercise tolerance in the evening. Ten healthy young males completed two, 2-day control and sleep deprivation trials. For the control trial, participants were allowed normal sleep from 23:00 to 07:00 h. For the sleep deprivation trial, participants did not sleep for 34 h. Autonomic activity was measured from 19:00 h on day 1 to 16:00 h on day 2 by frequency-domain measures of heart rate variability. Endocrine function was examined by measuring adrenocorticotropic hormone and cortisol from venous blood samples collected on day 2 at 09:00, 13:00, and 17:00 h and immediately after an exercise tolerance testing. Autonomic regulation, particularly parasympathetic regulation estimated from the high-frequency component of heart rate variability analysis, was significantly higher in the sleep deprivation trial than in the control trial in the morning and afternoon of day 2. Plasma adrenocorticotropic hormone concentrations were significantly higher at 09:00 and 13:00 h of day 2 under sleep deprivation. Heart rate during exercise was significantly lower following sleep deprivation. Therefore, the effects of sleep deprivation on autonomic regulation depend on the time of the day.  相似文献   
34.
This essay will shed light on the reasons why Brazilian football player Zico has become the ‘God of Soccer’ in Japan by discussing Zico’s unique character and actions and the social condition surrounding him, as well as the role played by the image of a hero held by the Japanese. The study uses the existing literature on Zico’s tenure in Japan along with Zico’s own writings and anecdotes to reflect upon his legacies from various angles. While it emphasizes the ability of an interpreter in constructing Zico’s image, it also encapsulates the key moments and images Zico elicited in Japan, including his brilliant style of play, his memorable hat-trick in his opening J-League match and his figure as a father of Japanese football. The essay will try to show that Zico’s emphasis on the importance of family, as in building a ‘Zico Family’, as well as his strong sense of obligation, professionalism and integrity contributed to creating his image as a legendary human being in Japan.  相似文献   
35.
Studies about mass media framing have found divergent levels of influence on public opinion; moreover, the evidence suggests that issue attributes can contribute to this difference. In the case of climate change, studies have focused exclusively on developed countries, suggesting that media influence perceptions about the issue. This study presents one of the first studies of media coverage in a developing country. It examines newspapers' reporting in Peru during the Fifth Latin America, Caribbean and European Union Summit in May 2008. The study focuses on the frames and the sources to provide an initial exploratory assessment of the coverage. The results show that the media relied mostly on government sources, giving limited access to dissenting voices such as environmentalists. Additionally, a prominence of "solutions" and "effects" frames was found, while "policy" and "science" frames were limited. The results could serve as a reference point for more comprehensive studies.  相似文献   
36.
The aim of the present study was to examine the relationships between muscle cross-sectional area (CSA) and muscular strength in terms of knee extension and flexion, hip extension and flexion, and hip abduction and adduction among well-trained soccer players. Fourteen university soccer players participated in the study, who had previously been divided into two groups based on ability (Group A: above-average ability; Group B: average ability). Maximal isokinetic and concentric muscular strength was measured in knee extension/flexion, hip extension/flexion and hip abduction/adduction using an isokinetic dynamometer at 1.57 and 4.19 rad x s(-1) (3.14 rad x s(-1)) in both the dominant and non-dominant leg. The CSAs of the thigh, gluteus muscles and iliopsoas muscles were calculated based on magnetic resonance imaging. There was no significant difference between the two groups in muscle CSA and isokinetic strength. Although there were some statistically significant differences between the dominant and non-dominant leg in terms of CSA and strength (P < 0.05-0.01), these were small and negligible. Apart from a non-significant relationship between the CSAs of the adductor muscles and hip adductor strength (r < 0.26, N.S.), the CSA of the other muscle groups correlated with maximal isokinetic strength (r = 0.38-0.64, P < 0.05). These results suggest that no difference in muscle characteristics (in terms of muscle CSA and strength) was apparent among well-trained soccer players, even between the dominant and non-dominant leg. There is also a case that the anatomical function of a single (or group of) muscle(s) may not be reflected by the strength-CSA relationship depending on the movements (such as hip adduction-adductor muscle CSA). Thus, further studies are required to develop methods to assess neuromuscular function in relation to muscle morphology among soccer players.  相似文献   
37.
We examined the ontogeny of the infant rhesus monkey's defensive behaviors and the ability to modulate them in response to specific environmental cues. Rhesus infants in 4 age groups (N = 8 per group) were briefly separated from their mothers and tested under 3 conditions: alone, in the presence of a human who averted his gaze, and in the presence of a human staring at them. Infants as young as 0 to 2 weeks displayed defensive behaviors but did not selectively respond to the human's presence or direction of gaze. By 9 to 12 weeks of age, infants modulated their responses in relation to the parameters of the threat. At this age, infant rhesus monkeys undergo cognitive and emotional changes associated with brain development similar to those in human infants 7 to 12 months old. This also is the time when human infants engage in complex emotional and behavioral responses to threatening situations. Understanding the development and expression of defensive behaviors in infant monkeys should be applicable to similar issues in emotional development of human infants.  相似文献   
38.
Most attacks by rat colony members on strange intruders are made by a single dominant male. Such dominance, and the attack behaviors themselves, develop in a relatively fixed sequence over sessions with strange intruders. The entire sequence of attack on intruders occurs earlier in the intruder sessions for older rat colonies than in those for newly established colonies: conversely, more attack is seen in colonies with prior intruder experience than for intruder-naive colonies of equivalent age. Thus both experience within the colony and specific experience with strange intruders influence the rate of development of attack on intruders by dominant colony rats.  相似文献   
39.
By using unique survey data, we conduct a detailed study of the gender salary gap within economics departments in Japan. Despite the presence of rigid pay scales emphasizing age and experience, there is a 7% gender salary gap after controlling for rank and detailed personal, job, institutional and human capital characteristics. This gender salary gap exists within ranks. We find no gender promotion differences. In addition, we find a concentration of the salary gap in public universities and in research oriented universities. Our results show no evidence that the gender salary gap is reducing over time, and reject the hypothesis that females’ choice between household work and market activities is responsible for the gender salary gap.  相似文献   
40.
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