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991.
This study investigated the influence of environmental factors on the foraging cycle, breeding activity, settlement and growth of the opisthobranch Hydatina physis using laboratory trials and field observations. Results showed that H. physis follows a nocturnal circadian rhythm mediated by photic intensity and modulated by food availability. The adults foraged between 1900 and 0530 h, with an activity peak between 2000 and 2200 h, and remained inactive and burrowed in the sand during the day. This pattern was clearly influenced by cloud cover, rain and laboratory manipulated light:dark cycle. The reproduction of H. physis was primarily influenced by the lunar cycle. For 4 consecutive months, hermaphroditic reciprocal copulation, preceded by pre-copulatory courtship behaviour, occurred at night 5–7 d before the full moon. Spawning occurred 3–5 d later for up to 5 consecutive nights, the egg mass gradually decreasing in size with each spawning. An overcast sky or rain prevented or delayed both copulation and egg release. Settlement of veligers was largely influenced by the nature of the substrate. In multiple-choice experiments, settlement occurred predominantly on sand containing cirratulid polychaetes. The juveniles reached ca. 3.9 mm in shell length after 5.5 months growth.  相似文献   
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In dormant embryos of Pyrus malus L. cv. Golden delicious laid flat on water agar and cultured under light, inhibition of growth, chlorophyll synthesis and pro-plastid development in the upper cotyledon was complete, whereas they occurred to a notable degree in the cotyledon in contact with the medium particularly between days 5 and 9 of culture. Radioimmunoassay of endogenous ABA showed a marked difference between the two cotyledons during the first days of culture: on day 2 the level in the upper cotyledon could be 8 times higher than in the lower cotyledon. Experiments using isolated cotyledons showed that this early difference may be responsible for the subsequent divergence in development of the two cotyledons. The effects of exogenous ABA differed depending on the physiological state of the material: when applied at the start of culture ABA inhibited subsequent development, but if applied after 5 days of incubation, when plastid differentiation was already established, ABA no longer prevented growth and only partially inhibited chlorophyll production. The results suggest a direct causal relationship between the levels of endogenous ABA and cotyledon development.  相似文献   
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Assessment of anxiety symptoms in autism spectrum disorders (ASD) is a challenging task due to the symptom overlap between the two conditions as well as the difficulties in communication and awareness of emotions in ASD. This motivates the development of a physiological marker of anxiety in ASD that is independent of language and does not require observation of overt behaviour. In this study, we investigated the feasibility of using indicators of autonomic nervous system (ANS) activity for this purpose. Specially, the objectives of the study were to 1) examine whether or not anxiety causes significant measurable changes in indicators of ANS in an ASD population, and 2) characterize the pattern of these changes in ASD. We measured three physiological indicators of the autonomic nervous system response (heart rate, electrodermal activity, and skin temperature) during a baseline (movie watching) and anxiety condition (Stroop task) in a sample of typically developing children (n = 17) and children with ASD (n = 12). The anxiety condition caused significant changes in heart rate and electrodermal activity in both groups, however, a differential pattern of response was found between the two groups. In particular, the ASD group showed elevated heart rate during both baseline and anxiety conditions. Elevated and blunted phasic electrodermal activity were found in the ASD group during baseline and anxiety conditions, respectively. Finally, the ASD group did not show the typical decrease in skin temperature in response to anxiety. These results suggest that 1) signals of the autonomic nervous system may be used as indicators of anxiety in children with ASD, and 2) ASD may be associated with an atypical autonomic response to anxiety that is most consistent with sympathetic over-arousal and parasympathetic under-arousal.  相似文献   
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Estuarine tapertail anchovy (Coilia nasus, junior synonym C. ectenes) is a widely distributed and commercially important aquaculture species, although its growth in aquaculture settings is so slow as to pose a serious practical problem. In order to understand the molecular mechanisms of growth, we cloned the myostatin gene in C. nasus (CnMSTN) by homologous cloning methods. Its full-length cDNA is 2252 bp, with a 1125-bp open reading frame (ORF) that encodes a 374-amino acid protein. The CnMSTN protein is predicted to contain domains typical of MSTN, including a TGFb-propeptide domain and a TGFB domain. Gene expression patterns were detected by RT-qPCR. CnMSTN is expressed strongly in the muscle and brain, and comparatively lower in the gills, liver, spleen, intestine, trunk kidney and head kidney. The effects of stress on the muscle and brain MSTN levels were evaluated by RT-qPCR. CnMSTN in the muscle was positively regulated by loading and transport stress, but brain CnMSTN expression was not affected. We found NaCl could reduce the death rate caused by loading and transporting stress, and in this group, CnMSTN mRNA expression in the muscle revealed increased, but decreased in the brain. Further, in the fasting experiment, the CnMSTN mRNA revealed decrease in the muscle, on the contrary, it showed increase in the brain. Selection upon variants of the MSTN gene has shown great potential in breeding work for mammals, and our results provide the basic knowledge for breeding of C. nasus.  相似文献   
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Patient experience reflects quality of care from the patients’ perspective; therefore, patients’ experiences are important data in the evaluation of the quality of health services. The development of an abbreviated, reliable and valid instrument for measuring inpatients’ experience would reflect the key aspect of inpatient care from patients’ perspective as well as facilitate quality improvement by cultivating patient engagement and allow the trends in patient satisfaction and experience to be measured regularly. The study developed a short-form inpatient instrument and tested its ability to capture a core set of inpatients’ experiences. The Hong Kong Inpatient Experience Questionnaire (HKIEQ) was established in 2010; it is an adaptation of the General Inpatient Questionnaire of the Care Quality Commission created by the Picker Institute in United Kingdom. This study used a consensus conference and a cross-sectional validation survey to create and validate a short-form of the Hong Kong Inpatient Experience Questionnaire (SF-HKIEQ). The short-form, the SF-HKIEQ, consisted of 18 items derived from the HKIEQ. The 18 items mainly covered relational aspects of care under four dimensions of the patient’s journey: hospital staff, patient care and treatment, information on leaving the hospital, and overall impression. The SF-HKIEQ had a high degree of face validity, construct validity and internal reliability. The validated SF-HKIEQ reflects the relevant core aspects of inpatients’ experience in a hospital setting. It provides a quick reference tool for quality improvement purposes and a platform that allows both healthcare staff and patients to monitor the quality of hospital care over time.  相似文献   
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