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121.
S. Tweddle C. James H. Daniels D. Davies P. Harvey N. James J. Mossman E. Woolf 《Computers & Education》2000,35(4)
This paper is an assessment of the use of CancerHelp UK, a Web site developed as a resource for people living with cancer. Attitudes to the use of the site were examined through interviews with 23 patients and relatives in a two-phase pilot study. The analysis of the data was conducted within a framework derived from activity theory which focused on individual perspectives, purposes and outcomes and the processes involved in use. Our findings show that the process of using the site and the characteristics of the medium were regarded as beneficial, although some inexperienced computer users needed some help. There were positive cognitive and affective outcomes for those who had independently chosen to use the site. However, there were differences in process and outcome between independent users and participants who had been invited to use the resource for evaluation purposes. The study raises questions about the use and evaluation of the World Wide Web for teaching and learning through an informal learning activity. The response of participants to the use of CancerHelp UK indicates that the resource is both useful and usable. The authors suggest that the availability of the Web as a means for learning about cancer may challenge the traditional transmission-based practice of the medical consultation. 相似文献
122.
Thoits Peggy A.; Hohmann Ann A.; Harvey Mary R.; Fletcher Bill 《Canadian Metallurgical Quarterly》2000,19(3):264
This field experiment examined effects of a support intervention on the physical and mental health of coronary artery bypass graft (CABG) surgery patients. Control participants (N?=?90) received usual hospital care; experimental participants (N?=?100) also received visits from a "similar other" while in the hospital. Similar others were Veterans Administration veterans who had CABG surgery previously and were trained in simple supportive techniques. Outcomes were assessed prior to surgery and at 1, 6, and 12 months afterwards. Unexpectedly, the intervention generally had no effects on participants' well-being. Further analysis showed that participants who talked often with fellow cardiac patients in the hospital ("de facto similar others") experienced improvements in their physical and emotional well-being over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Lemuel W Taylor Colin D Wilborn Travis Harvey Jennifer Wismann Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2007,4(1):10-9
Background
The purpose of this study was to examine the effects of a functional coffee beverage containing additional caffeine, green tea extracts, niacin and garcinia cambogia to regular coffee to determine the effects on resting energy expenditure (REE) and hemodynamic variables. 相似文献124.
The complexity of a social group may influence the vocal behavior of group members. Recent evidence in Carolina chickadees, Poecile carolinensis, indicated that one component of social complexity, group size, influenced the complexity of the "chick-a-dee" call, a vocalization functioning in social cohesion. Individuals in larger social groups used calls with greater information than did individuals in smaller social groups. Here, the authors review this earlier work, and describe a recent study indicating that social interactions between females and males within female-male pairs of chickadees were associated with rates of chick-a-dee call production in the males. Together, these studies suggest that the nature and complexity of social interactions among members of chickadee social groups influence chick-a-dee calling behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
125.
Effects of temperature changes on bacterial populations in three aquatic systems were studied in the Thermal Effects Laboratory of the USAEC's Savannah River Laboratory. At monthly intervals for 12 months, total plate counts and diversity of heterotrophic, mesophilic bacteria were determined from a natural stream, two artificial streams, and two outdoor ponds. Water for artificial systems was drawn from the natural stream.Effects of changes in ambient temperature were analyzed in natural and artificial streams and in an unheated pond. A second pond was heated above natural stream temperature. Temperature elevation resulted in increased total plate counts in each system. Bacterial diversity increased in all systems during the initial 3–4°C increase in temperature. However, a reduction in diversity occurred when temperature was maintained 4–10°C above the initial ambient temperature. Changes were observed in both nutritional types and genera. 相似文献
126.
Harvey JE 《Applied optics》1995,34(19):3715-3726
Residual surface roughness over the entire range of relevant spatial frequencies must be specified and controlled in many high-performance optical systems. This is particularly true for enhanced reflectance multilayers if both high reflectance and high spatial resolution are desired. If we assume that the interfaces making up a multilayer coating are uncorrelated at high spatial frequencies (microroughness) and perfectly correlated at low spatial and midspatial frequencies, then the multilayer can be thought of as a surface power spectral density (PSD) filter function. Multilayer coatings thus behave as a low-pass spatial frequency filter acting on the substrate PSD, with the exact location and shape of this cutoff being material and process dependent. This concept allows us to apply conventional linear systems techniques to the evaluation of image quality and to the derivation of optical fabrication tolerances for applications utilizing enhanced reflectance x-ray multilayers. 相似文献
127.
Invasive sea lamprey (Petromyzon marinus) remain an important source of fish mortality in the Laurentian Great Lakes, yet assessing their impact is hindered by lack of quantitative diet information. We examined nitrogen and carbon stable isotope ratios (δ15N and δ13C) of sea lamprey and host species in six ecoregions of Lake Superior, mainly in 2002–2004. Data implied that most sea lamprey fed primarily on upper trophic level species, including forms of lake trout (Salvelinus namaycush). However, in Ontario waters, particularly semi-enclosed Black Bay, sea lamprey relied heavily on lower trophic levels, such as coregonines (Coregonus spp.) and suckers (Catostomus spp.). Sea lamprey δ15N and δ13C generally increased with sea lamprey size, implying dependence on higher trophic levels later in life. Most parasitic sea lamprey that we captured were attached to either lean lake trout (35% of observed attachments), lake whitefish (Coregonus clupeaformis; 25%), or cisco (C. artedii; 25%); the latter sea lamprey were typically < 15 g. Survey- and fishery-dependent wounding rate data compiled from 1986–2005 suggest that lean and siscowet lake trout were selectively parasitized by sea lamprey, which is consistent with our stable isotope data. Our results largely support the notion that lake trout are the principal host species in Lake Superior. However, stable isotope evidence that sea lamprey feed at lower trophic levels in some regions argues for comprehensive monitoring of sea lamprey impacts throughout the fish community in systems that sea lamprey have invaded. 相似文献
128.
Mike Spillane Ryan Schoch Matt Cooke Travis Harvey Mike Greenwood Richard Kreider Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2009,6(1):6-14
Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester is alleged
to increase creatine bio-availability. This study examined how a seven-week supplementation regimen combined with resistance
training affected body composition, muscle mass, muscle strength and power, serum and muscle creatine levels, and serum creatinine
levels in 30 non-resistance-trained males. In a double-blind manner, participants were randomly assigned to a maltodextrose
placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were orally ingested at a
dose of 0.30 g/kg fat-free body mass (approximately 20 g/day) for five days followed by ingestion at 0.075 g/kg fat free mass
(approximately 5 g/day) for 42 days. Results showed significantly higher serum creatine concentrations in PLA (p = 0.007)
and CRT (p = 0.005) compared to CEE. Serum creatinine was greater in CEE compared to the PLA (p = 0.001) and CRT (p = 0.001)
and increased at days 6, 27, and 48. Total muscle creatine content was significantly higher in CRT (p = 0.026) and CEE (p
= 0.041) compared to PLA, with no differences between CRT and CEE. Significant changes over time were observed for body composition,
body water, muscle strength and power variables, but no significant differences were observed between groups. In conclusion,
when compared to creatine monohydrate, creatine ethyl ester was not as effective at increasing serum and muscle creatine levels
or in improving body composition, muscle mass, strength, and power. Therefore, the improvements in these variables can most
likely be attributed to the training protocol itself, rather than the supplementation regimen. 相似文献
129.
A previously undescribed cause of abnormal uterine bleeding is presented. Nine of 310 women evaluated by sonohysterography for abnormal bleeding demonstrated an 8 to 17 mm gap in the anterior lower uterine segment myometrium at the site of prior cesarean deliveries. All women were premenopausal and had a history of 2 to 12 days of postmenstrual spotting. Presumably a lack of coordinated muscular contractions occurs around the cesarean scar, allowing the defect to collect menstrual debris. Subsequently, the debris leaches out through the cervix for several days after the majority of menstrual flow has ceased. 相似文献
130.
Bone tumors of the coracoid process of the scapula are rare, and diagnosis and treatment often are delayed. The records of 18 patients with bone tumors of the coracoid process were reviewed. Histologic types included eight cases of ordinary chondrosarcoma, three cases of dedifferentiated chondrosarcoma, two cases of osteoid osteoma, and one case each of osteosarcoma, plasmacytoma, lymphoma, giant cell tumor, and aneurysmal bone cyst. All 18 patients had shoulder pain, and eight of them had been treated with steroid injections for nonneoplastic conditions. Radiologically, chondrosarcoma did not always show clear cortical destruction, and one giant cell tumor had features mimicking those of chondrosarcoma. Five patients (three with dedifferentiated chondrosarcoma, one with chondrosarcoma, one with plasmacytoma) died of disease. The coracoid process was the site with a markedly high proportion of chondrosarcomas. Bone tumors of the coracoid process may be difficult to detect on plain radiographs. In the patient with persistent shoulder pain unresponsive to the selected treatment, additional imaging studies should be considered to eliminate the possibility of a bone lesion. 相似文献