Use of diamond sensors for a high-flux, high-rate X-ray pass-through diagnostic.

X-ray free-electron lasers (XFELs) deliver pulses of coherent X-rays on the femtosecond time scale, with potentially high repetition rates. While XFELs provide high peak intensities, both the intensity and the centroid of the beam fluctuate strongly on a pulse-to-pulse basis, motivating high-rate beam diagnostics that operate over a large dynamic range. The fast drift velocity, low X-ray absorption and high radiation tolerance properties of chemical vapour deposition diamonds make these crystals a promising candidate material for developing a fast (multi-GHz) pass-through diagnostic for the next generation of XFELs. A new approach to the design of a diamond sensor signal path is presented, along with associated characterization studies performed in the XPP endstation of the LINAC Coherent Light Source (LCLS) at SLAC. Qualitative charge collection profiles (collected charge versus time) are presented and compared with those from a commercially available detector. Quantitative results on the charge collection efficiency and signal collection times are presented over a range of approximately four orders of magnitude in the generated electron-hole plasma density.

Emotional and coping responses to serial killings. The Gainesville murders.

Forensic experts have focused more on the psychological profile of a serial killer rather than on the pronounced effects on the community at large. Coping with a stressful event is thought to influence emotional states. However, little empirical understanding of this process exists. The present study examined changes in psychological factors 9 days after the occurrence of serial killings in a college community. Multivariate analyses of variance conducted on the variables of stress, anxiety, physical symptoms, and depression revealed a significant difference between the group tested after the murders and a cross-sectional cohort group. Univariate analyses revealed that the study class was significantly more depressed compared with the cohort group. The study class was also significantly more depressed compared with their own responses 1 year before the killings. For both classes, depression was significantly correlated with certain coping styles, including escape-avoidance and accept responsibility. Results have implications for certain coping behaviors (i.e., avoidant behaviors), such as that leaving the community may have been maladaptive and perhaps diverted attention from the more necessary active problem-solving behaviors (e.g., increasing security) in addition to increasing depression.

Psychological and physical benefits of circuit weight training in law enforcement personnel.

The effects of circuit weight training on mood, perceived stress, job satisfaction, and physical symptoms were investigated in a sample of state law enforcement officers. Forty-three male officers who were not regularly exercising were assigned to either 4 months of circuit weight training or a wait-list control condition. Four months of circuit weight training led to a significant increase in strength on cardiovascular fitness. Subjects also demonstrated significant improvements in mood, including decreases in somatization, anxiety, depression, and hostility. Circuit weight training also resulted in a decrease in reports of physical symptoms and in improvements in job satisfaction. Results indicated that subjects who dropped out of the exercise training program evidenced significantly greater anxiety, depression, and hostility at pretreatment than subjects who completed the program. These findings suggest that circuit weight training programs may contribute to important psychological benefits.

Assessment of quality of life as observed from the baseline data of the Studies of Left Ventricular Dysfunction (SOLVD) trial quality-of-life substudy.

The improvement of aspects of a patient's quality of life may be as important as prolonging survival in evaluating clinical trials of heart failure. The purpose of this study was to analyze the psychometric properties of the baseline measures from the quality-of-life substudy from the Studies of Left Ventricular Dysfunction (SOLVD) trial. The measures included the 6-Minute Walk Test, Dyspnea Scale, Living with Heart Failure, Physical Limitations, Psychologic Distress and Health Perceptions, as reported by both patients and staff. Cognitive functioning, such as Vocabulary, Digit Span and Trails Making, was also assessed. Patients were classified as New York Heart Association class I (n = 158) versus II or III (n = 150). The internal consistencies (i.e., reliabilities) of the self-report measures were high, except for the Health Perceptions of Class II or III patients. Reliability of the SOLVD quality-of-life battery was confirmed by significantly better life quality among New York Heart Association class I patients versus class II or III patients combined on the Walk Test, Physical Limitations, Dyspnea, Living with Heart Failure, Psychologic Distress and staff perceptions of patient health. In accordance with prior studies, the measures were uncorrelated with left ventricular ejection fraction. By demonstrating strong internal consistencies, reliability based on physician reports, and independence of ejection fraction levels, use of this quality-of-life assessment battery in this and other clinical trials of compromised ventricular functioning is supported.

Lumbar strengthening in chronic low back pain patients. Physiologic and psychological benefits.

The effects of exercise for isolated lumbar extensor muscles were examined in 54 chronic low-back pain patients. Subjects were randomly assigned to a 10-week exercise program (N = 31) or a wait-list control group (N = 23). Results indicated a significant increase in isometric lumbar extension strength for the treatment group and a significant reduction in reported pain compared with the control group (P 0.05). Treated subjects reported less physical and psychosocial dysfunction whereas the control group increased in pain, and physical and psychosocial dysfunction. There were no concomitant changes in reported daily activity levels. These results show that lumbar extension exercise is beneficial for strengthening the lumbar extensors and results in decreased pain and improved perceptions of physical and psychosocial functioning in chronic back pain patients. However, these improvements were not related to changes in activities or psychological distress.

Perceived social support, social skills, and quality of relationships in bulimic women.

The impaired relationship between bulimics and their environment may be important factors in the onset and perpetuation of bulimia. This study explored specific aspects of the bulimic's social network and interpersonal relationships as well as individual difference variables that might mediate her ability to obtain support or perceive this as adequate. Ss were 21 bulimic women and 21 control Ss who completed self-report measures assessing perceived social support, the quality of relationships, social skills, and psychopathology. Bulimics reported less perceived support from friends and family, more negative interactions and conflict, and less social competence. Differences in negative interactions remained significant after controlling for overall psychopathology, and level of conflict was an important predictor of group membership. In addition, bulimics were rated as less socially effective by observers unaware of their group membership. Results highlight the need for further investigation of the quality and type of interactions in bulimic women's lives.

An examination of hardiness and neuroticism as potential moderators of stress outcomes.

The perception of stress is believed to result in negative consequences as a result of complex interactions among a number of variables. This study of a random sample of 234 male highway patrol officers examined the relationship among stress measures (perception of stress, report of daily hassles, and items unique to police work) and the specific consequences of stress (burnout, physical symptoms, and job dissatisfaction). Our hypothesis was that hardiness and neuroticism would moderate the relationship between stress and its consequences and that the Perceived Stress Scale (PSS) would emerge as a significant predictor of the strain experienced. The two moderator variables we examined exerted clearer main effects, rather than moderating influences, on the outcome measures. The authors found that the PSS was an important and significant predictor of stress-induced consequences.

Supportive and problematic social interactions: a social network analysis.

Assessed the number of sources of supportive and problematic social interactions in the total social network as well as the number who were the sources of consistently supportive or problematic interactions in a sample of 2nd year medical students. Number of problematic interaction sources was hypothesized to be more predictive of psychological and physical well-being than number of supportive interaction sources. Results showed that total supportive and total problematic interaction sources were equally predictive of life satisfaction. The presence of at least one individual who is a consistent source of problematic interactions was most predictive of lower life satisfaction. Results indicate the importance of studying both supportive and problematic social interactions. They also suggest that interactions with individuals that are consistently problematic may negatively impact upon well-being.

Cardiovascular reactivity and silent ischemia in response to mental stress in symptomatic and asymptomatic coronary artery disease patients: results of a pilot study.

The current study was designed to examine cardiovascular reactivity to psychological tasks and its relationship to provocation of ischemia in asymptomatic coronary artery disease (CAD) patients with documented silent ischemia and those with painful ischemia. ECG, heart rate, and blood pressure responses to mental stress were collected for 13 patients with coronary artery disease (CAD) and for 6 healthy control subjects. Six of the CAD patients were asymptomatic (documented silent ischemia and no history of angina), while the remaining 7 were symptomatic (history of angina). Three types of mental stress were employed: white noise (a passive stressor), digits repeated backwards (an active stressor), and a math task plus white noise (active + passive stressor). Results indicate that significant increases in heart rate and blood pressure, but not silent ischemic episodes, were induced by the mental stress tasks. In addition, patients with documented exercise-induced and ambulant silent ischemia showed trends of blunted autonomic responsiveness to the stressors. On the digits backwards task, the CAD patients with silent ischemia showed significantly lower diastolic blood pressure responses compared with controls or angina patients. Findings suggest that ischemic episodes are not easily induced by brief mental stress. However, results indicate that asymptomatic CAD patients with silent ischemia may be lacking in autonomic responsiveness, particularly in terms of peripheral resistance, to mental stress in comparison with health controls and symptomatic ischemic patients. Further investigation is needed to explore how patients with silent ischemia typically respond autonomically to mental stress and how blunted reactivity may relate to the provocation of unrecognized ischemic episodes.

Psychologic assessment of candidates for heart transplantation: toward a normative data base.

Psychologic variables appear to play a role in mediating outcome of heart surgery and organ transplantation. Psychologic data, therefore, can be useful in providing optimal care for transplant candidates during hospitalization and recovery. Psychologic assessment of transplantation candidates is difficult because of the lack of normative data specific to this population. This problem is addressed in the present article. A standard protocol for the assessment of heart transplant candidates is described and some preliminary normative data on the tests used in this protocol are presented.

Silent myocardial ischemia. Rationale for management.

Recent studies show that in many coronary artery disease patients with any form of angina, myocardial infarction, or positive exercise tests but no symptoms, most of the ischemic episodes are silent. Furthermore, evidence is building to suggest that in many patient groups, silent ischemia relates to prognosis. Numerous therapies, including nitroglycerin or isosorbide dinitrate, have been shown to modify silent ischemia and its associated risks. Studies indicate that frequency and perhaps duration of silent ischemic episodes can be modified by treatment with beta-adrenergic blockers or calcium antagonists alone or, even more effectively, with a combination of both types of agent. Many ischemic episodes persist, however, when therapy is directed only at reduction of angina. Evidence suggests that some characteristics of silent ischemia predict prognosis, whereas angina characteristics do not. Until additional data about prognosis and the influence of treatment on prognosis are available, the appropriate focus seems to be improvement of outcome in those patients who are at highest risk, rather than only reduction of chest pain.

An examination of the factor structure and convergent and discriminant validity of the SCL-90R in an outpatient clinic population.

This study investigated the factor structure of the SCL-90R using an outpatient psychology clinic population. Six relatively homogeneous and stable factors were identified: Depression, Somatization, Anger-Hostility, Paranoid-Psychoticism, Phobic Anxiety, and Obsessive-Compulsive. However, a principal component analysis revealed that the first factor accounted for a large percentage of the variance, suggesting that this instrument measures a general dimension of psychopathology. In addition, significant correlations between the SCL-90R symptom dimensions and both the BDI and several MMPI scales were found. The results of the study lead to questions regarding the utility of the SCL-90R.

Beta-adrenergic blockers in silent myocardial ischemia.

Factors contributing to the development of exercise-induced painful ischemia, such as actions of the central nervous system and catecholamines, have been well identified, but the mechanisms by which nonexercise-related silent episodes of ischemia are provoked are unknown. Possible mechanisms receiving much study in recent years are those having the potential to influence the myocardial oxygen supply-demand relation. Beta-adrenergic receptor stimulations, by increasing myocardial oxygen demand through augmentation of heart rate and contractility (beta 1), may mediate responses that cause ischemia or perpetuate ischemic episodes induced by other means. Other receptors (beta 2) may mediate coronary and peripheral vascular constriction, limiting myocardial oxygen supply and further increasing myocardial oxygen demand. Studies have investigated the effect of beta blockade on ischemic episodes in patients with a variety of clinical forms of coronary heart disease. Beta blockade has been shown to reduce the frequency and duration of silent and painful ischemic episodes in patients with effort angina and rest angina. The data suggest that heart rate and perhaps other changes observed with use of beta blockade play an important role in silent ischemia; heart rate at specific times throughout the day, particularly in the late A.M., and the increase in heart rate seen in conjunction with silent ischemic episodes are all decreased with administration of beta blockade. Results of a recent study focusing only on silent ischemia showed that beta-blocker treatment with metoprolol, compared with placebo, significantly reduced total silent ischemic time (frequency and duration of episodes) in all periods examined.

Heart transplantation candidates: psychological evaluation.

Most medical centers that perform heart transplantation have established medical review boards that consider medical, psychosocial, and financial factors in choosing appropriate candidates. The psychological evaluation described here can furnish clinically useful baseline data regarding the patient's emotional and cognitive functioning, and identify other individual and family variables that may affect patient compliance and the outcome of transplantation.

Diagnostic issues in eating disorders: two cases of atypical eating disorder.

Two cases with significant eating disturbances are described. Both possess several characteristic symptoms of anorexia but lack a primary drive for thinness or body image disturbances. Similarly, neither engaged in recurrent episodes of binge eating which is typical of bulimia. The authors propose the differential diagnoses of atypical eating disorder rather than conversion disorder as a more descriptive and accurate diagnostic label.

The relationship of anxiety to childhood depression.

In order to investigate the relationship between anxiety and depression in emotionally disturbed children, 30 hospitalized inpatient children were individually administered the Children's Depression Inventory (CDI), the Children's Manifest Anxiety Scale-Revised (CMAS-R), and the State-Trait Anxiety Inventory for Children (STAIC). Results indicated a significant relationship between CDI scores, the CMAS-R and its factors, and the STAIC. Correlations between the various factors of anxiety and depression suggest a complex relationship between the two constructs. Stepwise regression analyses indicated further the complexity of this relationship. Results were discussed in terms of the possible differential role which the different anxiety factors play in depression.