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151.
施栋涛  赵冲  尹东红  陈阳  常亚青 《生态学报》2022,42(10):4160-4168
海胆在海藻床生态系统结构和功能调控中发挥重要作用。深入理解流速对海胆摄食和生长的影响具有重要的生态学研究价值。研究了长时间(49 d)不同流速(2 cm/s, 10 cm/s和20 cm/s)对光棘球海胆幼胆(Mesocentrotus nudus,壳径:约20 mm)摄食行为、摄食量和生长的影响,以评估不同流速下,海胆摄食行为和生长的差异。实验结果表明,流速对光棘球海胆的存活无显著影响,但显著影响其生长。2 cm/s下海胆的壳径和体重显著大于10和20 cm/s。在实验开始后的第2周和第3周,2 cm/s下海胆的体重和壳径已显著高于20 cm/s。流速显著影响光棘球海胆的摄食量(P<0.001)和觅食行为(20 cm/s,P=0.004),但口器咬合行为未受显著影响(P=0.113)。管足附着时间在流速为10 cm/s和20 cm/s下显著长于其在2 cm/s。同样的,相较于2 cm/s(P=0.02)和10 cm/s(P=0.03),20 cm/s的流速可显著削弱光棘球海胆的翻正行为。综上,高流速(20 cm/s)通过影响海胆管足活动削弱其觅食行为(而非摄食行为),进而降低其...  相似文献   
152.
意大利蜜蜂和中华蜜蜂为蓝莓授粉的行为比较研究   总被引:1,自引:0,他引:1  
应用意大利蜜蜂和中华蜜蜂为蓝莓授粉,对其授粉行为和活动方式进行了比较研究。结果表明:(1)采集过程中意蜂和中蜂的行为存在差异,意蜂头部探进铃铛花,将喙伸入花管中吸食花蜜,头部粘附花粉,花粉一部分被收集到花粉框,另一部分被带到其他花上;中蜂采集行为不同,一部分采集蜂探入铃铛花采食,采集时间短暂,另一部分采集蜂停靠在花托部位,采食花瓣掉落的花朵,不易粘附花粉和携带花粉。(2)授粉活动方式不同,意大利蜜蜂每分钟平均访花数为5.05±0.14次,中华蜜蜂为4.77±0.13次,两者差异不显著;而意蜂单次访花时间为9.16±0.43 s极显著长于中蜂的4.89±0.22 s,意蜂较中蜂在花朵的采集时间长,采集间隔时间短,而中蜂较意蜂寻找花朵的时间长,采集间隔时间长。单位面积意蜂采集蜂数量为平均12.00±0.90头,中蜂采集蜂数量平均为1.73±0.42头,两者差异极显著。同时意蜂蓝莓花粉携粉率27.51%,中蜂采集蓝莓花粉携粉率为11.38%,意蜂的授粉蜂数量及授粉专一性优于中蜂。本研究阐明了蓝莓花期不同蜂种的授粉行为及活动方式,据此得出意蜂为蓝莓授粉的行为和活动特性优越于中蜂,两者相比意蜂具有更高的授粉效率。  相似文献   
153.
2006 年9 ~11 月在四川省若尔盖县铁布自然保护区,对四川梅花鹿发情期的声行为进行了初步观测,结果表明:在发情期,四川梅花鹿的发声行为可分为雌、雄鹿的报警叫声,雄鹿的吼叫声和求偶叫声。雌鹿的报警叫声持续时间257 ~ 539 ms,频率范围1409. 5 ~ 4474. 6 Hz,主频率3534. 8 ±89.12 Hz;雄鹿的报警叫声持续时间136 ~187 ms,频率范围271.8 ~3910.5 Hz,主频率3244.3 ±79.32 Hz;两者在持续时间、最低频率、最高频率上差异极显著(P < 0.01),在间隔时间上差异不显著(P = 0.624)。吼叫是雄鹿的主要发情行为之一。雄鹿每次吼叫1 声,持续时间1580 ~4972 ms,频率范围234.6 ~6171.4 Hz,主频率2264.6 ± 166.44 Hz。雄鹿吼叫声的主频率存在显著的个体差异(P <0.01)。在整个吼叫过程中,一只雄鹿的吼叫常会引起周围其它雄鹿的吼叫反应。雄鹿每日吼叫的次数与其在繁殖群中的等级序列有关,不同序列等级雄鹿的吼叫频次存在显著差异(P<0.01)。雄鹿的吼叫声在白天和夜晚均能听到,但主要发生在06:00 ~ 08:00、17:00 ~ 19:00 和01:00 ~ 03:00 三个时间段。四川梅花鹿雄鹿的求偶叫声有4 种,其生物学意义与发情炫耀、追逐、激惹和爬跨等行为有关。  相似文献   
154.
日本三角涡虫摄食行为的影响因素   总被引:3,自引:0,他引:3  
研究了光强度、温度变化、食物种类、饥饿程度以及破坏耳突对日本三角涡虫(Dugesia japonica)涡虫摄食行为的影响。弱光和低温最利于涡虫摄食;4种人工饲料中,涡虫偏爱食熟的鸡蛋蛋黄;在一定范围内,饥饿时间长短与摄食强度呈正相关;破坏耳突后涡虫的摄食能力基本消失,“脑”对涡虫摄食是否有作用尚待进一步研究。  相似文献   
155.
We provide here the first bottom-up review of the lived experience of mental disorders in adolescents co-designed, co-conducted and co-written by experts by experience and academics. We screened first-person accounts within and outside the medical field, and discussed them in collaborative workshops involving numerous experts by experience – representing different genders, ethnic and cultural backgrounds, and continents – and their family members and carers. Subsequently, the material was enriched by phenomenologically informed perspectives and shared with all collaborators. The inner subjective experience of adolescents is described for mood disorders, psychotic disorders, attention-deficit/hyperactivity disorder, autism spectrum disorders, anxiety disorders, eating disorders, externalizing disorders, and self-harm behaviors. The recollection of individuals’ past histories also indexes the prodromal (often transdiagnostic) features predating the psychiatric diagnosis. The experience of adolescents with mental disorders in the wider society is described with respect to their family, their school and peers, and the social and cultural context. Furthermore, their lived experience of mental health care is described with respect to receiving a diagnosis of mental disorder, accessing mental health support, receiving psychopharmacological treatment, receiving psychotherapy, experiencing peer support and mental health activism, and achieving recovery. These findings can impact clinical practice, research, and the whole society. We hope that this co-designed, co-conducted and co-written journey can help us maintain our commitment to protecting adolescents’ fragile mental health, and can help them develop into a healthy, fulfilling and contributing adult life.  相似文献   
156.
2007年5月下旬至6月下旬,针对新组群并放归于卡拉麦里有蹄类保护区第二放归点的普氏野马(Equus przewalskii)繁殖群,采用焦点动物取样法和全事件记录法,观测记录了组群和放归初期繁殖群内个体间的争斗行为(攻击行为和屈服行为),以优势指数法确定繁殖群内的个体等级序列。结果表明,新组群内个体的年龄与攻击行为发出次数不存在显著的相关性(r=0.60,t=1.62,rr0.05),攻击与屈服行为次数也无显著的相关性(r=0.56,t=1.41,rr0.05)。各个体之间从最初组群到野放争斗行为日趋减少,社群等级逐渐建立并趋于稳定。  相似文献   
157.
The weaning period for gray whale (Eschrichtius robustus) calves is important for maternal instruction and learning. We examined observational and acoustic data from a foraging site for evidence of calf development and mother-young information transfer. Site survey data demonstrated an initial prioritization of calf protection by using shallow shoreline areas. Foraging in more open water was only noted in late summer, perhaps an indicator of the maturation of the calf. Other indicators of development were found in acoustic recordings made over two summers. Motherese call types have been reported from recordings made in breeding lagoons, but have not before been described outside of calving regions. They were present in recordings from this study site, predominantly in the early summer and not heard past late July. We suggest vocal repertoire may evolve as the calf ages, and more adult calling behaviors eventually replace motherese. Long-term mark-recapture analyses demonstrated a high return of calves to the area to forage in summers subsequent to weaning, suggesting maternally inherited prey preference and site use behaviors. From our findings we suggest a calf's first summer is a highly critical period for development and may be formative in shaping future behaviors and habitat use patterns.  相似文献   
158.
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159.
The aim of this study was to increase understanding of the associations between different dimensions of morningness–eveningness, depressive symptoms, and emotional eating in the general population. The participants were 25-to-74-year-old Finnish men (n?=?2325) and women (n?=?2699) from the National FINRISK Study conducted in 2007. The Center for Epidemiological Studies – Depression Scale and the Three-Factor Eating Questionnaire-R18 were used to measure depressive symptoms and emotional eating. Chronotype was assessed with a shortened version of Horne and Östberg’s Morningness–Eveningness Questionnaire (MEQ). Structural equation modeling was used as an analytical approach. Confirmatory factor analysis indicated a two-factor structure for the six-item MEQ with separate factors for morning alertness and circadian preference for daily activities (r?=?0.65). Higher alertness in the morning and preference for morning hours were both related to lower depressive symptoms (βtotal effect?=??0.36 and ?0.11, respectively) and emotional eating (βtotal effect?=??0.20 and ?0.09; βindirect effect through depressive symptoms = ?0.12 and ?0.04, respectively), even though the relationships with morning alertness were stronger. However, the associations of circadian preference with depressive symptoms and emotional eating were reversed after adjustment for morning alertness. Finally, among participants who rarely or never experienced sleeping sufficiently, those in the lowest (i.e. eveningness) and higher (i.e. morningness) circadian preference/morning alertness quartiles had the highest depressive symptom scores. In conclusion, the findings emphasize the importance of separating between different dimensions of chronotype when examining its relationships with psychological factors such as depressive symptoms and overeating tendencies.  相似文献   
160.
Objective: To investigate the influence of patient obesity on primary care physician practice style. Research Methods and Procedures: This was a randomized, prospective study of 509 patients assigned for care by 105 primary care resident physicians. Patient data collected included sociodemographic information, self‐reported health status (Medical Outcomes Study Short Form‐36), evaluation for depression (Beck Depression Index), and satisfaction. Height and weight were measured to calculate the BMI. Videotapes of the visits were analyzed using the Davis Observation Code (DOC). Results: Regression equations were estimated relating obesity to visit length, each of the 20 individual DOC codes, and the six DOC Physician Practice Behavior Clusters, controlling for patient health status and sociodemographics. Obesity was not significantly associated with the length of the visit, but influenced what happened during the visit. Physicians spent less time educating obese patients about their health (p = 0.0062) and more time discussing exercise (p = 0.0075). Obesity was not related to discussions regarding nutrition. Physicians spent a greater portion of the visit on technical tasks when the patient was obese (p = 0.0528). Mean pre‐visit general satisfaction for obese patients was significantly lower than for non‐obese patients (p = 0.0069); however, there was no difference in post‐visit patient satisfaction. Discussion: Patient obesity impacts the medical visit. Further research can promote a greater understanding of the relationships between obese patients and their physicians.  相似文献   
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