PCB布线设计(之五)

要解决信号完整性问题，最好有多个工具分析系统性能。如果在信号路径中有一个A/D转换器，那么当评估电路性能时，很容易发现三个基本问题：所有这三种方法都评估转换过程，以及转换过程与布     

Differential effects of yohimbine and naloxone on copulatory behaviors of male rats.

Prior research has demonstrated that both yohimbine, an alpha?-adrenergic antagonist, and naloxone, an opiate antagonist, facilitate components of copulatory behaviors in nonstressed male rats. In the present experiments, it is demonstrated that these drugs differentially affect copulatory behaviors when the behavioral testing situation contained an aversive element. Male rats received an injection of lithium chloride (0.3 M, 20 ml/kg, ip) immediately after each encounter with an estrous female. Consequently, male copulatory behaviors gradually declined during successive test sessions. These male rats also received ip injections of either yohimbine (2 mg/kg/ml), naloxone (4 mg/kg/ml), or isotonic saline 20 min prior to each copulation test. Yohimbine-treated rats were more likely to copulate than control rats during both acquisition and extinction of lithium chloride-induced associative inhibition of copulatory behavior. Conversely, naloxone-treated rats were less likely to copulate than control rats during both acquisition and extinction. Data are consistent with the hypothesis that yohimbine increases sexual motivation in the male rat and limit the generality of the excitatory effects of naloxone on copulatory behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Video-as-data: Technical and social aspects of a collaborative multimedia application

We studied the use of a collaborative multimedia system for coordinating teamwork among members of a neurosurgical team. We analyze the use of video within the operating room and the use of broadcast audio and video to other locations in the hospital to enable remote neurophysiological monitoring. We describe how the multimedia system was used in a real world work context, including its benefits and problems. We argue that video can be useful as more than just pictures of people talking to one another; video can be a rich tool to enable analysis and problem solving. We discuss privacy problems inherent in collaborative multimedia technology and describe how they played out in the hospital during the course of our study.     

Analysis of the association between marital relationships and health problems: An interactional perspective.

Reviews the evidence for a relationship between 3 types of marital variables (marital status, marital adjustment, and marital interaction) and health problems (etiology, course/outcome/treatment) as well as the effect that health problems have on marriage. The mechanisms responsible for these associations also are evaluated. The evidence suggests that marital variables affect health status but that the effect is indirect and nonspecific. The major explanatory model, the stress/social support hypothesis, has provided a broad conceptual framework rather than testable hypotheses. The results of the review suggest, however, that sufficient evidence exists for researchers to focus on exploring specific explanations. A hypothetical model is presented that includes interpersonal, intrapersonal, psychological, and physiological variables. This model is intended as a blueprint for exploration as well as a summary of available evidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

MODELING LONG-MEMORY PROCESSES FOR OPTIMAL LONG-RANGE PREDICTION

Abstract. We look at the implications of modeling observations from a fractionally differenced noise process using an approximating AR ( p ) model. The approximation is used because of computational difficulties in the estimation of the differencing parameter of the fractional noise model. Because the fractional noise process is long-range dependent, we assess the applicability of the approximating autoregressive (AR) model based on its long-range forecasting accuracy compared with that of the fractional noise model. We derive the asymptotic k -step-ahead prediction error for a fractional noise process modeled as an AR( p ) process and compare it with the k -step-ahead prediction error obtained when the model for the observed series is correctly specified as a fractional noise process and the fractional differencing parameter d is either known or estimated. We also assess the validity of the asymptotic results for a finite sample size via simulation. We see that AR models can be useful for long-range forecasting of long-memory data, provided that consideration is given to the forecast horizon when choosing an approximating model.     

Lightning arrester failure and ferroresonance on a distributionsystem

Since 1987 the Upper Peninsula Power Company (UPPCO) has been experiencing a large number of lightning arrester failures on a portion of their distribution system in southern Marquette County, Michigan, USA. It was in the area of the US Navy's extremely low frequency (ELF) antenna, where the distribution system had been reconfigured so that the transformers were connected line-to-line in order to eliminate interference from the antenna. A study determined that the system was susceptible to ferroresonance during single line faults under lightly loaded conditions and that the overvoltages experienced could be causing the lightning arrester failures. This conclusion was further strengthened by a statistical study which compared the actual number of failures to an expected number of failures, given the systems loading condition and fault rate     

The relevance of food for children's cognitive and behavioural health.

Explores 4 areas in which psychologists have contributed to an understanding of the relationship between food and children's behavior: (1) malnutrition and mental development, in which behavioral scientists have investigated the long-term sequelae of severe deprivation; (2) cognitive performance and mood, including discoveries about the effects of carbohydrates; (3) hyperactivity, arousal, and attention, in which B. F. Feingold's (1976) hypothesis has been evaluated; and (4) nonnutritive effects of dietary fiber in the treatment of recurrent abdominal pain and encopresis. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differentiation of Alzheimer's, Huntington's, and Parkinson's disease patients on the basis of verbal learning characteristics.

Examined the degree to which patients with dementia could be differentiated on the basis of their verbal learning characteristics. 83 patients with Parkinson's disease (PD), 22 with Huntington's disease (HD), and 22 with probable Alzheimer's disease were administered the California Verbal Learning Test. PD and HD Ss were divided into subgroups to control for the severity of overall memory impairment. Intrusions, perseverations, and rate of forgetting were the most discriminating variables. Profile differences between HD and PD were sufficiently robust to separate these 2 groups. Results do not support a simplistic cortical–subcortical dichotomy; rather, individual dementing syndromes have unique patterns of verbal learning performance that are distinct from one another. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Psychological profiles of violent and nonviolent maritally distressed couples.

Compared 42 couples seeking counseling who had equal levels of marital distress but different levels of violence. 32 couples had experienced at least 1 episode of physical assault in the last year. Measures included the Profile of Mood States, the Index of Self-Esteem, assessments of violence in family and peer milieus, and assessment of alcohol use. More violent males reported alcohol problems than distressed males. Women in violent couples were significantly more anxious, confused, fatigued, and marginally more depressed than maritally distressed women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)