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101.
102.
We argue that affect plays a vital role in attitudes toward organ donation and that reluctance to become an organ donor is likely to be related to the experience of affective ambivalence. Assessing the affect associated with organ donation could help to predict donor-relevant decisions. Results of a confirmatory factor analysis on 464 students showed that affective evaluations can be distinguished both from cognitive evaluations and from overall evaluations. As expected, affective evaluations revealed ambivalence (using the ‘Griffin’ measure of ambivalence) toward organ donation, whereas the two other types of evaluations did not. Results of a follow-up study using logistic regression (n?=?85), showed that affective evaluations predicted donor-relevant decisions six months later. The present findings support the proposal to include separate affective evaluations in measures of attitudes to organ donation. More general implications for the measurement and structure of attitudes in health related domains are discussed.  相似文献   
103.
Prismatic dislocation loops are the primary manifestation of radiation damage in crystals, and contribute to the phenomenon of radiation embrittlement. This undesirable effect, most serious for materials used in high-dose environments such as next-generation fission and future fusion reactors, results from the strong interaction between gliding dislocations, the carriers of plasticity, with the population of radiation-induced prismatic loops. Ferritic–martensitic steels, the most promising candidate materials for future high-dose applications, are based on iron and are known to become highly elastically-anisotropic at the high temperatures (>500°C) at which they must operate. In this article, we develop a novel modelling approach based on anisotropic elasticity theory to predict the shapes of prismatic loops in anisotropic crystals, paying particular attention to the technologically important case of α-iron. The results are compared with transmission electron microscope observations of the damage structure sustained by ultra-high-purity iron irradiated to a dose of approximately two displacements per atom.  相似文献   
104.
Helium retention in metals is related to their atomic structure and the type of defects they contain. In order to investigate the dependence of helium retention on structure, amorphous Fe79B16Si5 and crystalline FeBSi alloys were irradiated by helium ions at room temperature. In the crystalline alloy irradiated with 5 keV He+ ions, three types of helium trapping sites were found: surface defects produced by the irradiation, interstitial-type dislocation loops, and voids. Although these defects did not exist in the amorphous FeBSi alloy, we did observe thermal desorption peaks related to all three types. In addition, helium was released during the crystallization of amorphous FeBSi that had been irradiated by He+ ions.  相似文献   
105.
Healthy untrained men (N = 11) were asked to perform 10 series of 12 repetitions of knee eccentric extension (EE) at 160° per second. Quadriceps muscle torques evoked by electrical stimulation at 20 Hz (P20) and 100 Hz (P100), maximal voluntary isometric contraction torque (MVC), maximal isokinetic concentric torque (IT) at 30° per second, voluntary activation index (VA), simple reaction time (RTs), complex reaction time (RTc), and torque variability at 30% of MVC were measured before EE, immediately after EE, and 60 min and 24 hr after EE. MVC, IT, P20, P100, and VA decreased significantly after EE and remained depressed 24 hr later. Torque variability increased significantly after EE. Average RTs and RTc did not change after EE, whereas intraindividual variability in RTs and RTc increased significantly after EE.  相似文献   
106.
The authors investigated whether and, if so, how velocity information is used to control predictive manual pointing movements and saccades. Participants (N = 6) intercepted an occluded moving target as if it were still visible. They kept their eyes fixated while the target moved. The target traveled over a fixed distance and changed its velocity on the way. The presentation time of the final velocity was varied. Both the eye and the hand overshot the slow target and undershot the fast target, particularly when the duration of the final velocity was short. Thus, responses were biased in the direction of the target's initial velocity. The error seemed to arise because participants did not take their latency into account when aiming at the target. Instead, they strategically aimed farther ahead when the target was fast. Amplitude was also more related to the position of velocity change than to final velocity duration. Both findings suggest that target velocity is not extrapolated but that individuals add an increment to the position of velocity change.  相似文献   
107.
Almost 60,000 people in the United States with end stage renal disease are waiting for a kidney transplant. Because of the scarcity of organs from deceased donors live kidney donors have become a critical source of organs; in 2001, for the first time in recent decades, the number of live kidney donors exceeded the number of deceased donors. The paradigm used to justify putting live kidney donors at risk includes the low risk to the donor, the favorable risk-benefit ratio, the psychological benefits to the donor, altruism, and autonomy coupled with informed consent; because each of these arguments is flawed we need to lessen our dependence on live kidney donors and increase the number of organs retrieved from deceased donors.

An “opting in” paradigm would reward people who agree to donate their kidneys after they die with allocation preference should they need a kidney while they are alive. An “opting in” program should increase the number of kidneys available for transplantation and eliminate the morally troubling problem of “organ takers” who would accept a kidney if they needed one but have made no provision to be an organ donor themselves. People who “opt in” would preferentially get an organ should they need one at the minimal cost of donating their kidneys when they have no use for them; it is a form of organ insurance a rational person should find extremely attractive.

An “opting in” paradigm would simulate the reciprocal altruism observed in nature that sociobiologists believe enhances group survival. Although the allocation of organs based on factors other than need might be morally troubling, an “opting in” paradigm compares favorably with other methods of obtaining more organs and accepting the status quo of extreme organ scarcity. Although an “opting in” policy would be based on enlightened self-interest, by demonstrating the utilitarian value of mutual assistance, it would promote the attitude that self-interest sometimes requires the perception that we are all part of a common humanity.  相似文献   
108.
读者在阅读中面临如何选择眼跳落点位置的问题。研究者在有词间空格的字母文字中(如英语和德语)发现人们倾向于将眼跳落在词中心偏左的位置,这个位置被称为偏好注视位置(preferred viewing location,PVL)。中文文本并没有空格来标记词边界信息,这使得中文阅读的眼跳目标选择机制更加复杂。近年来,研究者从中央凹—副中央凹动态调节的角度研究了阅读中眼跳目标选择的机制。结果发现在中文阅读中眼跳目标选择受到中央凹和副中央凹信息加工的共同影响,而副中央凹的加工直接决定了眼跳落点位置。  相似文献   
109.
The bisection of lines positioned radially (with the two ends of the line close and far, with respect to the participant's body) has been less investigated than that of lines placed horizontally (with their two ends left and right, with respect to the body's midsagittal plane). In horizontal bisection, patients with left neglect typically show a rightward bias for both lines and words, greater with longer stimuli. As for radial bisection, available data indicate that neurologically unimpaired participants make a distal error, while results from right‐brain‐damaged patients with left spatial neglect are contradictory. We investigated the bisection of radially oriented words, with the prediction that, during bisection, linguistic material would be recoded to its canonical left‐to‐right format in reading, with the performance of neglect patients being similar to that for horizontal words. Thirteen right‐brain‐damaged patients (seven with left spatial neglect) and fourteen healthy controls were asked to manually bisect 40 radial and 40 horizontal words (5–10 letters), and 80 lines, 40 radial and 40 horizontal, of comparable length. Right‐brain‐damaged patients with spatial neglect exhibited a proximal bias in the bisection of short radial words, with the proximal part corresponding to the final right part of horizontally oriented words. This proximal error was not found in patients without neglect and healthy controls. For bisection, short radial words may be recoded to the canonical orthographic horizontal format, unveiling the impact of left neglect on radially oriented stimuli.  相似文献   
110.
Therapy resistance of approximately one‐third of patients with Gilles de la Tourette syndrome (GTS) requires consideration of alternative therapeutic interventions. The article demonstrates the role of the cerebellum in neuropsychiatric disorders and GTS in particular, specifically its role in functions relating to motor and cognitive symptoms. Certain circuits in the cerebellum have been shown to undergo learning‐induced changes during conditioning, with cells in the cortex of the cerebellum appearing to decrease their activity whilst those in deep nuclei seem to do the inverse. Evidence exists showing that abnormal excitability of the motor cortex via the cerebellum could be expected to participate in motor tics in GTS possibly due to aberrations in certain structures of involved circuits. The role of the cerebellum in learning and plasticity processes renders it a strategic and valuable structure to consider for brain stimulation when investigating potential treatment options for neuropsychiatric disorders such as GTS. This article puts forth the concept of using non‐invasive and invasive brain stimulation techniques as a novel platform for non‐pharmacological neuromodulation of GTS symptoms.  相似文献   
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