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991.
Huermann Rosalia; Crook Lyon Rachel E.; Heath Melissa Allen; Fischer Lane; Potkar Kirti 《Dreaming》2009,19(2):85
In this study, 49 public school mental health practitioners (school counselors, school psychologists, and school social workers) completed a survey about working with students’ dreams. The majority of these practitioners reported having at least one student bring up dreams during counseling, more frequently with troubling dreams and nightmares or when coping with grief. Results showed that practitioners were less likely to talk about dreams with students who had been identified with an adjustment disorder, psychosis, or eating disorder; those who were oppositional or ill; and those who struggled with substance abuse problems. Although most practitioners did not feel competent working with children’s dreams and reported minimal training in dream work, they were interested in learning more about children’s dreams and potential uses of dream work in supportive counseling. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
Drought perturbation driven by the El Niño Southern Oscillation (ENSO) is a principal stochastic variable determining the dynamics of lowland rain forest in S.E. Asia. Mortality, recruitment and stem growth rates at Danum in Sabah (Malaysian Borneo) were recorded in two 4-ha plots (trees ≥ 10 cm gbh) for two periods, 1986–1996 and 1996–2001. Mortality and growth were also recorded in a sample of subplots for small trees (10 to <50 cm gbh) in two sub-periods, 1996–1999 and 1999–2001. Dynamics variables were employed to build indices of drought response for each of the 34 most abundant plot-level species (22 at the subplot level), these being interval-weighted percentage changes between periods and sub-periods. A significant yet complex effect of the strong 1997/1998 drought at the forest community level was shown by randomization procedures followed by multiple hypothesis testing. Despite a general resistance of the forest to drought, large and significant differences in short-term responses were apparent for several species. Using a diagrammatic form of stability analysis, different species showed immediate or lagged effects, high or low degrees of resilience or even oscillatory dynamics. In the context of the local topographic gradient, species’ responses define the newly termed perturbation response niche. The largest responses, particularly for recruitment and growth, were among the small trees, many of which are members of understorey taxa. The results bring with them a novel approach to understanding community dynamics: the kaleidoscopic complexity of idiosyncratic responses to stochastic perturbations suggests that plurality, rather than neutrality, of responses may be essential to understanding these tropical forests. The basis to the various responses lies with the mechanisms of tree-soil water relations which are physiologically predictable: the timing and intensity of the next drought, however, is not. To date, environmental stochasticity has been insufficiently incorporated into models of tropical forest dynamics, a step that might considerably improve the reality of theories about these globally important ecosystems. 相似文献
994.
Anastasija?ZaikoEmail author Darius?Daunys Sergej?Olenin 《Helgoland Marine Research》2009,63(1):85-94
Habitat engineering role of the invasive zebra mussel Dreissena polymorpha (Pallas) was studied in the Curonian lagoon, a shallow water body in the SE Baltic. Impacts of live zebra mussel clumps and
its shell deposits on benthic biodiversity were differentiated and referred to unmodified (bare) sediments. Zebra mussel bed
was distinguished from other habitat types by higher benthic invertebrate biomass, abundance, and species richness. The impact
of live mussels on biodiversity was more pronounced than the effect of shell deposits. The structure of macrofaunal community
in the habitats with >103 g/m2 of shell deposits devoid of live mussels was similar to that found within the zebra mussel bed. There was a continuous shift
in species composition and abundance along the gradient ‘bare sediments—shell deposits—zebra mussel bed’. The engineering
impact of zebra mussel on the benthic community became apparent both in individual patches and landscape-level analyses. 相似文献
995.
The aim of this study was to quantify the effect of bottom and suspended mussel cultures, cultured in different physical environments,
on the sedimentary environmental conditions and thereby the biodiversity structure of the associated macrofaunal community.
We compared two bottom cultures (Limfjorden: microtidal, wind-driven; Oosterschelde: macrotidal) and one suspended culture
(Ria de Vigo in an upwelling coastal region). The sedimentary environmental conditions (mud fraction, POC, PON, phosphorus
content, chl a breakdown products) were significantly elevated underneath and surrounding bottom and suspended cultures compared to culture-free
sediments that were nearby and hydrodynamically similar. The relative change in environmental conditions was more pronounced
in the Oosterschelde compared to Limfjorden, most likely due to differences in hydrodynamic forcing and characteristics of
the mussel bed. The effect of the suspended cultures in Ria de Vigo on the surrounding sediments was influenced by local topographic
and hydrodynamic conditions. The impact of mussels on the benthic community due to biodeposition was clearly seen in the community
structure. The species composition changed from species which are typically present in sandy environments to more small opportunistic
species, which are typically present in organically enriched sediments. The impact of bottom cultures on the benthic community
due to changes in the habitat under the presence of mussels was positive, especially in the Oosterschelde where an increase
in the number of epibenthic species was seen. The influence of bottom cultures on the sedimentary environment and on the macrobenthic
community seems to be very local. Within the mussel site in Limfjorden, differences were detected between sites where none
or almost no mussels were present with sites where mussels were very abundant. 相似文献
996.
Gerhard‐Wilhelm Weber Süreyya Özöğür‐Akyüz Erik Kropat 《Birth defects research. Part C, Embryo today : reviews》2009,87(2):165-181
An emerging research area in computational biology and biotechnology is devoted to mathematical modeling and prediction of gene‐expression patterns; it nowadays requests mathematics to deeply understand its foundations. This article surveys data mining and machine learning methods for an analysis of complex systems in computational biology. It mathematically deepens recent advances in modeling and prediction by rigorously introducing the environment and aspects of errors and uncertainty into the genetic context within the framework of matrix and interval arithmetics. Given the data from DNA microarray experiments and environmental measurements, we extract nonlinear ordinary differential equations which contain parameters that are to be determined. This is done by a generalized Chebychev approximation and generalized semi‐infinite optimization. Then, time‐discretized dynamical systems are studied. By a combinatorial algorithm which constructs and follows polyhedra sequences, the region of parametric stability is detected. In addition, we analyze the topological landscape of gene‐environment networks in terms of structural stability. As a second strategy, we will review recent model selection and kernel learning methods for binary classification which can be used to classify microarray data for cancerous cells or for discrimination of other kind of diseases. This review is practically motivated and theoretically elaborated; it is devoted to a contribution to better health care, progress in medicine, a better education, and more healthy living conditions. Birth Defects Research (Part C) 87:165–181, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
997.
Objective: This study examined experiences of weight stigmatization, sources of stigma, coping strategies, psychological functioning, and eating behaviors in a sample of 2671 overweight and obese adults. Research Methods and Procedures: The total sample was partitioned into two subsamples for investigation. Sample I was comprised of 2449 adult women, and Sample II was a matched sample of adult men and women (N = 222) that was disaggregated to investigate gender differences. Both samples completed an online battery of self‐report questionnaires measuring frequency of weight stigmatization and coping responses to deal with bias, the most common sources of the bias, symptoms of depression, self‐esteem, attitudes about weight and obesity, and binge eating behaviors. Results: Experiences of weight stigmatization, in many forms and across multiple occasions, was common in both samples. A variety of coping strategies were used in response. More frequent exposure to stigma was related to more attempts to cope and higher BMI. Physicians and family members were the most frequent sources of weight bias reported. No gender differences were observed in types or frequency of stigmatization. Frequency of stigmatization was not related to current psychological functioning, although coping responses were associated with emotional well‐being. Discussion: These findings raise questions about the relationship between stigma and psychological functioning and have important implications for obesity treatment and stigma reduction intervention efforts, both of which are discussed. 相似文献
998.
Rothert K Strecher VJ Doyle LA Caplan WM Joyce JS Jimison HB Karm LM Mims AD Roth MA 《Obesity (Silver Spring, Md.)》2006,14(2):266-272
Objective: To assess the efficacy of a Web‐based tailored behavioral weight management program compared with Web‐based information‐only weight management materials. Research Methods and Procedures: Participants, 2862 eligible overweight and obese (BMI = 27 to 40 kg/m2) members from four regions of Kaiser Permanente's integrated health care delivery system, were randomized to receive either a tailored expert system or information‐only Web‐based weight management materials. Weight change and program satisfaction were assessed by self‐report through an Internet‐based survey at 3‐ and 6‐month follow‐up periods. Results: Significantly greater weight loss at follow‐up was found among participants assigned to the tailored expert system than among those assigned to the information‐only condition. Subjects in the tailored expert system lost a mean of 3 ± 0.3% of their baseline weight, whereas subjects in the information‐only condition lost a mean of 1.2 ± 0.4% (p < 0.0004). Participants were also more likely to report that the tailored expert system was personally relevant, helpful, and easy to understand. Notably, 36% of enrollees were African‐American, with enrollment rates higher than the general proportion of African Americans in any of the study regions. Discussion: The results of this large, randomized control trial show the potential benefit of the Web‐based tailored expert system for weight management compared with a Web‐based information‐only weight management program. 相似文献
999.
Kathleen Sullivan Eric van Heugten Kimberly Ange‐van Heugten Matthew H. Poore Ellen S. Dierenfeld Barbara Wolfe 《Zoo biology》2010,29(4):457-469
The objectives of the present research were to conduct a survey to investigate the health history and feeding practices of giraffe in captivity in North America and to obtain samples of hay, concentrate, browse, urine, and serum to compare across zoos, possible factors relating to the development of urolithiasis. Forty‐one out of 98 institutions contacted responded, representing 218 giraffe. All responding zoos fed concentrate and alfalfa hay was the primary forage. Sixty‐five percent of zoos fed browse and 43 different species of browse were listed. Six zoos reported a history of urolithiasis, seven reported wasting syndrome, and 10 reported sudden death. The median daily amount (as fed) of concentrate and hay offered were 5.45 kg (range of 2.73–9.55 kg) and 6.82 kg (range of 2.53–12.50 kg), respectively. The concentrate:hay ratio of the offered diet ranged from 0.22 to 3.47 with a median value of 0.79. Forty‐three percent of the institutions offered a ratio greater than 1:1. Samples of concentrate and hay (six zoos), serum (five zoos), and urine (seven zoos) were obtained for chemical analyses. Analyzed nutrient content of the consumed diet, measured by weighing feed and orts for three consecutive days, met recommendations for giraffe, but was excessive for crude protein and P. Concentrate:hay and serum P were positively correlated (r=0.72; P<0.05). High dietary P content and a high level of concentrate relative to hay may be contributing factors to urolith formation and warrant further investigation. Zoo Biol 29:457–469, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
1000.
Sephra N. Rampersad 《Journal of Phytopathology》2010,158(5):329-333
This study investigated the natural occurrence of Verticillium dahliae (Kleb.) infection in pumpkin (Cucurbita pepo L.) seed. The mean incidence of infection was found to be 21.0%. Isolates recovered from seeds were pathogenic to pumpkin (cultivar ‘Jamaican squash’). Surface sterilization by immersion in 0.6% sodium hypochlorite for 20 min eradicated V. dahliae from infected pumpkin seeds without affecting germinability. Plating of seed components revealed that the fungus was present in the seed coat but not in the embryo or cotyledons. In a growing‐on test, 25% of 6‐week‐old plants grown from untreated seeds were infected. Germination and production of normal seedlings were unaffected by V. dahliae infection of seeds. Verticillium dahliae in pumpkin seed was found to be external and transmissible to plants. The findings of this study are important in devising disease control strategies. 相似文献