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Metazoan meiofauna and in particular nematode densities, diversity, community structure were studied in relation to water depth (20 m, 50 m, 500 m, 1000 m and 2000 m) along four bathymetric transects in the Western Indian Ocean off the Kenyan coast. Nematode densities ranged between 276–944 ind./10 cm2, which is comparable to values from other oligotrophic areas in the world. Densities was correlated with oxygen concentrations in the overlying water, since they were lowest at mid‐depth (500–1000 m) coinciding with the minimum oxygen level. Nematode community structure (at genus level) resembles communities found in temperate slope regions, which are also characterized by a low productivity. The community structure showed correlations with sediment composition, water depth and oxygen levels in the overlying water. Sediment composition was mainly important at the shelf where nematodes separated into a silty sediment‐dwelling community with high abundances of Daptonema, Dorylaimopsis, Terschellingia and Halalaimus, and a sandy sediment‐dwelling community characterised by high abundances of Microlaimus and Halalaimus. The genera Monhystera, Acantholaimus, Sabatieria, Molgolaimus and Halalaimus dominated the slope communities. The characteristic deep‐sea taxa, the monhysterids and Acantholaimus increased in relative abundance with increasing depth, to become dominant at the lower slope (2000 m). The upper (500 m) and mid‐slope (1000 m), which coincided with the lowest oxygen concentrations, were colonised by Sabatieria, a genus that is known to inhabit suboxic sediments. Diversity at the level of the genera showed an unimodal trend along the sampled gradient, with highest values at mid‐depth (500 m). Although the oxygen minimum at mid depths is much less pronounced than in adjacent areas, the results of this study suggest an impact on the present communities.  相似文献   
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Form C of the Multidimensional Health Locus of Control Scales (MHLC-C) was designed to investigate health-related control beliefs of persons with an existing medical condition. The aim of the present study was to examine the psychometric properties of this instrument in a culture characterized by external control beliefs and learned helplessness—contrary to the societal context of original test development. Altogether, 374 Hungarian patients with cancer, irritable bowel syndrome, diabetes, and cardiovascular and musculoskeletal disorders were enrolled in the study. Besides the MHLC-C, instruments measuring general control beliefs, anxiety, depression, self-efficacy, and health behaviors were also administered to evaluate the validity of the scale. Both exploratory and confirmatory factor analytic techniques were used to investigate the factor structure of the scale. Our results showed that the Hungarian adaptation of the instrument had a slightly different structure than the one originally hypothesized: in the present sample, a three-factor structure emerged where the items of the Doctors and the Others subscales loaded onto a single common component. Internal reliability of all three subscales was adequate (alphas between .71 and .79). Data concerning the instrument''s validity were comparable with previous results from Western countries. These findings may suggest that health locus of control can be construed very similarly to Western countries even in a post-communist society—regardless of the potential differences in general control beliefs.  相似文献   
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