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991.
OBJECTIVE: Children and adolescents of the Gaza Strip have been subjected to continuous violence since the eruption of the second Intifada (Uprising). Little is known, however, about the psychological effects of this violence on children and adolescents of Gaza. Thus, the purpose of the present investigation was to evaluate and describe the psychological effects of exposure of war-like circumstances on this population. METHOD: Participants for this study were 229 Palestinian adolescents living in the Gaza Strip who were administered measures of post-traumatic stress disorder (PTSD), depression, anxiety, and coping. RESULTS: Of the 229 participants, 68.9% were classified as having developed PTSD, 40.0% reported moderate or severe levels of depression, 94.9% were classified as having severe anxiety levels, and 69.9% demonstrated undesirable coping responses. A canonical discriminant analysis revealed that adolescents diagnosed with PTSD tended to be those who reported the highest levels of depression, anxiety, and positive reappraisal coping, and the lowest levels of seeking guidance and support coping. CONCLUSIONS: These results indicate that a significant proportion of Palestinian adolescents living in the Gaza Strip are experiencing serious psychological distress.  相似文献   
992.
This article reports on the findings of an international online survey of early career researchers (ECRs) with regard to their authorship and peer review, attitudes, and practices, which sought to discover how the new wave of researchers were utilizing these key aspects of the scholarly communications system. A questionnaire was developed on the back of a 3‐year longitudinal, qualitative study and was distributed through publisher lists, social media networks, university networks, and specialist ECR membership organizations. Identical English, Polish, Russian, Chinese, Spanish, and French versions of the questionnaire were used. Results from 1,600 respondents demonstrated that 82.7% had co‐authored a paper, and most had performed a variety of authorship tasks. Almost half the respondents reported being subject to various authorship policies, although a quarter said they were not aware of any such policies. Almost all Chinese ECRs reported being subject to authorship policies, but only a third of UK ECRs reported the same. Three‐quarters of ECRs had experience in responding to peer review, and half had been peer reviewers. Half the respondents had a good experience of review and viewed it as a valuable way to improve their authorship skills. However, there was some criticism of some shortcoming such as lengthy peer review and superficial or uninformed comments by reviewers. Double‐blind review was the preferred methodology, and there were few suggestions for how to improve the review process.  相似文献   
993.
A study from the Harbingers research project provides a comprehensive assessment of the main features of the scholarly communications system as viewed by early career researchers (ECRs) in the final year of the study (2018). Aspects covered are: discovery and access, authorship practices, peer review, publishing strategies, open access publishing, open data, sharing, collaboration, social media, metrics, impact, reputation, libraries, publishers, and scholarly transformations. Nearly 120 science and social science researchers from seven countries were questioned about these 16 aspects. It was found that some scholarly features work well for ECRs, and in this category can be included: discovery and access, authorship practices, sharing, collaboration, and publishers. Reputation, publishing strategies, and impact are more problematical, and they, in turn, cause tensions regarding some other factors – social media, open access, and open data. Of the rest, libraries are largely invisible, and ECRs have conflicting views concerning ethical behaviour. Few envisage that transformational change will take place in the next 5 years.  相似文献   
994.
A mixed analysis of the perceived characteristics of effective college faculty members was conducted through surveying 615 students, predominantly Hispanic, enrolled in courses at two southwest Hispanic‐serving universities. Beliefs were identified that led to 29 prevailing themes: Knowledgeable; Understanding; Communication; Teaches Well; Caring; Organised; Flexibility; Positive Attitude; Patience; Experience in the Classroom; Fair; Helping; Respectful; Open‐minded; Builds Relationships; Passion for the Job; Service; Makes Learning Interesting; Uses Different Modalities; Fun; Motivating; Intelligent; Involving Students; Being Available; Friendly; Connects with the Real World; Listening; Creativity; and Challenges Student. Of these themes, knowledgeable, Understanding, Communication and Teaches Well received the highest endorsements and are congruent with student evaluations that are components of promotion and tenure decisions.  相似文献   
995.
Prostate carcinoma is the most frequently diagnosed malignancy and the second leading cause of death as a result of cancer in men in the US and other parts of the world. There are conflicting reports on the serum levels of testosterone and 17β-estradiol (E2) in benign prostatic hyperplasia (BPH) and prostate cancer. This study was designed to evaluate the serum concentrations of these hormones in patients with these disorders. Serum levels of prostate specific antigen (PSA), total testosterone and estradiol were determined in 228 subjects comprising of 116 subjects with BPH, 62 subjects with prostate cancer (CaP) and 50 age-matched apparently healthy controls, using ELISA methods. PSA levels were significantly elevated (p < 0.05) in BPH subjects than controls, while there was no significant difference (p > 0.05) in testosterone and estradiol levels of these subjects. PSA and estradiol levels were significantly higher (p < 0.05) in CaP subjects than in controls, while there was no observed significant difference (p > 0.05) in testosterone levels. CaP subjects had significantly raised PSA, testosterone, and estradiol levels than BPH subjects. The mean molar ratio of testosterone: E2 was lowest among CaP patients (134:1) and highest among controls (166:1). Significant positive correlation between PSA and 17β-estradiol was observed in prostate disorders (BPH and CaP patients: r = 0.347; p = 0.000). Significant negative correlations between testosterone and PSA were also observed among BPH patients (r = −0.221, p = 0.049) and control subjects (r = −0.490, p = 0.000). No significant correlation existed between testosterone and PSA in CaP patients (r = 0.051, p = 0.693). Correlations between age and estradiol in both BPH and CaP were not significant (p > 0.05). This study has shown that, there was a significant increase in serum estradiol in CaP subjects, while the testosterone levels in both BPH and CaP subjects were not different from those of controls.  相似文献   
996.
Older persons receiving services in community settings, rather than Nursing Homes, are at risk of social isolation. Computer mediated communication offers technological resources that recipients of Home and Community-Based Services (HCBS) might use to reduce their social isolation. The present study involved personal interviews with 40 HCBS clients regarding their interest in communicating with members of their social networks and using computers. At the time of the interview, 30 of the 40 participants did not use computers and reported cost, lack of training, physical limitations, lack of interest and access, and fraud as the reasons for not using computers. After watching a videotape illustrating an easy-to-use computer interface that allows older persons to communicate with families and friends, 90% reported that it would be helpful for people like them. Participants said such a computer would be helpful because it would make communication with friends and family easy, it could accommodate visual and manual disabilities, and would be interesting. Eighty-five percent said they would use a system like the one they were shown if it were available to them.  相似文献   
997.
This article used several data sets from a large-scale state testing program to examine the feasibility of combining general and modified assessment items in computerized adaptive testing (CAT) for different groups of students. Results suggested that several of the assumptions made when employing this type of mixed-item CAT may not be met for students with disabilities that have typically taken alternate assessments based on modified achievement standards (AA-MAS). A simulation study indicated that the abilities of AA-MAS students can be underestimated or overestimated by the mixed-item CAT, depending on students’ location on the underlying ability scale. These findings held across grade levels and test lengths. The mixed-item CAT appeared to function well for non-AA-MAS students.  相似文献   
998.
This study aims to (1) determine whether isometric training at a short vs. long quadriceps muscle length affects concentric torque production; (2) examine the relationship between muscle hypertrophy and concentric torque; and (3) determine whether changes in fascicle length are associated with changes in concentric torque.

Sixteen men performed isometric training at a short (SL, n = 8) or a long muscle length (LL, n = 8). Changes in maximal concentric torque were measured at 30, 60, 90, 120, 180, 240 and 300 rad · s?1. The relationships between the changes in concentric torque, cross-sectional area, volume and fascicle length were tested.

Concentric torque increased significantly after training only in LL and at angular velocities of 30 and 120 rad · s?1 by 12–13% (P < 0.05). Muscle size increased in LL only, the changes were correlated (r = 0.73–0.93, P < 0.05) with the changes in concentric torque. Vastus lateralis (VL) fascicle length increased in both groups (5.4 ± 4.9%, P = 0.001) but the change was not correlated with changes in concentric torque in either group.

Isometric training-induced increases in muscle size and concentric torque were best elicited by training at long muscle lengths. These results highlight a clear muscle length dependence of isometric training on dynamic torque production.  相似文献   
999.
The purpose of this investigation was to analyse the concurrent validity and reliability of an iPhone app (called: My Jump) for measuring vertical jump performance. Twenty recreationally active healthy men (age: 22.1 ± 3.6 years) completed five maximal countermovement jumps, which were evaluated using a force platform (time in the air method) and a specially designed iPhone app. My jump was developed to calculate the jump height from flight time using the high-speed video recording facility on the iPhone 5 s. Jump heights of the 100 jumps measured, for both devices, were compared using the intraclass correlation coefficient, Pearson product moment correlation coefficient (r), Cronbach’s alpha (α), coefficient of variation and Bland–Altman plots. There was almost perfect agreement between the force platform and My Jump for the countermovement jump height (intraclass correlation coefficient = 0.997, P < 0.001; Bland–Altman bias = 1.1 ± 0.5 cm, P < 0.001). In comparison with the force platform, My Jump showed good validity for the CMJ height (= 0.995, P < 0.001). The results of the present study showed that CMJ height can be easily, accurately and reliably evaluated using a specially developed iPhone 5 s app.  相似文献   
1000.
The aim of this study was to determine the role played by the entry-and-stretch phase in the coordination of swimming, at the different paces of race. Three national level swimmers (two men and one woman) were recorded, in lateral and bottom views, in three swimming paces: sprint (50 m and 100 m), middle-distance (200 m and 400 m) and long-distance (800 m and 1500 m). Anatomical landmark positions were obtained by manual digitalisation of the videos. Computational fluid dynamics and experimental studies (with a strain gauge balance and particle image velocimetry method) were used to measure and to calculate the external forces applied to the hand and to the forearm and to visualise the flow around the profile. Entry-and-stretch is the phase which varies the most according to the swimming pace. This phase can be decomposed into two sub-phases: one, the extension forward coordinated with the insweep of the opposite arm, and another one, the rotation downward coordinated with the upsweep. Results show that, at the three paces, this phase is not propulsive and could contribute essentially to maintain the horizontal balance of the body.  相似文献   
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