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61.
Abstract: Aerial surveys have been used to estimate abundance of several wild bird species including wild turkeys (Meleagris gallopavo). We used inflatable turkey decoys at 3 study sites in the Texas Rolling Plains to simulate Rio Grande wild turkey (M. g. intermedia) flocks. We evaluated detectability of flocks and errors in counting flock size during fixed-wing (Cessna 172) aerial surveys using logistic and linear regression models. Flock detectability was primarily influenced by flock size and vegetative cover, and errors in counting flock size were primarily influenced by size of flocks. We conducted computer simulations to evaluate the accuracy and precision of fixed-wing aerial surveys and examined power to detect trends in population change. Our simulations suggested abundance estimates from fixed-wing aerial surveys may be underestimated by 10-15% (2.0-4.8% CV). Power analyses suggested that fixed-wing aerial surveys can provide sufficient power (>0.80) to detect a population change of 10-25% over a 4-5-year period. We concluded fixed-wing aerial surveys are feasible on ecoregion scales.  相似文献   
62.
米小其  邓学建  郭克疾  牛艳东  周毅 《四川动物》2007,26(2):377-378,I0007
2005年1~2月,在Nikon体视镜下对挂榜山小鲵的早期胚胎发育过程进行了观察,对不同发育时期进行了数码拍照。根据胚胎发育的外部形态及典型特征将挂榜山小鲵早期胚胎发育过程分为21个时期。在水温6.5~10℃的条件下,受精卵历时1134h孵化出膜,初孵幼鲵全长约16.50mm。  相似文献   
63.
Our newly developed underwater high definition video camera system took the first live images of adults of the mesopelagic large squid, Taningia danae, between 240 and 940 m deep off Ogasawara Islands, western North Pacific. The resulting footage includes attacking and bioluminescence behaviours, and reveals that T. danae is far from the sluggish neutrally buoyant deep-sea squid previously suspected. It can actively swim both forward and backward freely by flapping its large muscular triangular fins and changes direction quickly through bending its flexible body. It can attain speeds of 2-2.5 ms(-1) (7.2-9 km h(-1)) when attacking bait rigs. They emitted short bright light flashes from their large arm-tip photophores before final assault, which might act as a blinding flash for prey as well as a means of measuring target distance in a dark deep-sea environment. They also emitted long and short glows separated by intervals while wandering around the double torch lights attached to the bait rig, suggestive of potential courtship behaviours during mating.  相似文献   
64.
In this study, we report on an in situ monitoring system of living cultured cells using infrared absorption spectroscopy in the geometry of multiple internal reflections (MIR-IRAS). In order to observe living cultured cells, the temperature in the sample chamber of a FT-IR spectrometer was maintained at 37 °C and a humidified gas mixture containing 5% CO2 was introduced into the sample chamber. Human breast cell line MCF-7 cultured on Si MIR prisms were placed in the sample chamber and infrared spectra of MCF-7 cells were collected for 5 h. It was found that the adhesion and metabolism of MCF-7 cells could be monitored by the absorption intensity of amide-II protein band (1,545 cm−1) and also by the absorption intensities of CH x bands (2,700–3,100 cm−1). These results suggest that our system is useful for a nondestructive and non-label monitoring of cell viability. Our method based on infrared absorption spectroscopy has a potential for bioscreening application.  相似文献   
65.
66.
郭慧  王兵  牛香 《生态学报》2015,35(20):6829-6837
森林生态系统定位观测研究站可为森林经营和生态效益评估提供基础数据。以湖北省为例,设计森林生态系统定位观测研究网络的指标体系,基于球状模型进行普通克里格插值,与GIS的空间叠置分析相耦合,生成湖北省生态地理区划和生态功能区划;建立森林生态站网络规划的有效分区,进行森林生态站站点布设,构建了湖北省森林生态系统定位观测研究网络;总结讨论了该网络的合理性和保障措施、与其它生态站网络的比较和网络规划的局限性。结果表明:该网络将湖北省划分成12个分区,共布设16个森林生态站,其中计划建设12个生态站,已经建设4个生态站;不仅可以监测湖北省81.8%的森林面积,88.9%的生态功能区面积,98.2%的重点生态功能区面积和87.5%的生物多样性保护优先区面积,而且9个森林生态站分布与湖北省4个重点生态功能区和3个生物多样性保护优先区相匹配。该网络可以实现森林生态系统生态要素的连续观测与清查,为森林生态服务功能和生态效益评估,以及重大生态工程提供数据支撑和辅助决策分析依据。  相似文献   
67.
Extreme climatic events can trigger abrupt and often lasting change in ecosystems via the reduction or elimination of foundation (i.e., habitat‐forming) species. However, while the frequency/intensity of extreme events is predicted to increase under climate change, the impact of these events on many foundation species and the ecosystems they support remains poorly understood. Here, we use the iconic seagrass meadows of Shark Bay, Western Australia – a relatively pristine subtropical embayment whose dominant, canopy‐forming seagrass, Amphibolis antarctica, is a temperate species growing near its low‐latitude range limit – as a model system to investigate the impacts of extreme temperatures on ecosystems supported by thermally sensitive foundation species in a changing climate. Following an unprecedented marine heat wave in late summer 2010/11, A. antarctica experienced catastrophic (>90%) dieback in several regions of Shark Bay. Animal‐borne video footage taken from the perspective of resident, seagrass‐associated megafauna (sea turtles) revealed severe habitat degradation after the event compared with a decade earlier. This reduction in habitat quality corresponded with a decline in the health status of largely herbivorous green turtles (Chelonia mydas) in the 2 years following the heat wave, providing evidence of long‐term, community‐level impacts of the event. Based on these findings, and similar examples from diverse ecosystems, we argue that a generalized framework for assessing the vulnerability of ecosystems to abrupt change associated with the loss of foundation species is needed to accurately predict ecosystem trajectories in a changing climate. This includes seagrass meadows, which have received relatively little attention in this context. Novel research and monitoring methods, such as the analysis of habitat and environmental data from animal‐borne video and data‐logging systems, can make an important contribution to this framework.  相似文献   
68.
目的:观察治疗肩锁关节脱位的不同手术方式的治疗效果,以确定最佳的手术方法。方法:将60例肩锁关节脱位病人随机分为治疗组和对照组,分别采用缝合锚结合联合腱外侧半肌腱反转移位重建喙锁韧带辅助颈腕吊带制动的治疗方法及克氏针张力带内固定方法,术后3个月及6个月对患者进行JOA总体情况评定、JOA评分比较、肩锁关节疼痛VAS评定情况比较及安全性评价。结果:应用缝合锚结合联合腱外侧半肌腱反转移位重建喙锁韧带辅助颈腕吊带制动治疗肩锁关节脱位3个月及6个月后JOA总体评定情况结果及.JOA评分结果优于克氏针张力带治疗方法;应用缝合锚结合联合腱外侧半肌腱反转移位重建喙锁韧带辅助颈腕吊带制动治疗肩锁关节脱位3个月及6个月后肩锁关节疼痛程度均轻于同时期克氏针张力带治疗方法。结论:缝合锚结合联合腱外侧半肌腱反转移位重建喙锁韧带辅助颈腕吊带制动治疗肩锁关节脱位是一种安全有效的临床治疗方法。  相似文献   
69.
目的:通过临床研究探讨电针治疗膝关节骨性关节炎的最佳参数,为临床提供更加规范性的治疗,进一步提高电针疗效。方法:将符合膝关节骨性关节炎诊断标准的73例单膝患者随机分为电针疏波组、密波组两组,均针刺患侧膝眼穴,疏波组接2Hz连续波治疗,密波组接40Hz连续波治疗,采用WOMAC评分对两组治疗后疼痛、僵硬、躯体功能进行评估,同时判断1个疗程及3个疗程治疗效果。结果:经统计学处理,完成第一疗程后,两组疼痛评分比较,P均<0.01,说明两组在疼痛疗效上存在差异。而两组僵硬和躯体功能评分的比较,P>0.05,显示两组没有统计学意义。第3疗程后,两组WOMAC总分比较,P均<0.01,具有极显著性差异,第3疗程症状积分低于第1疗程,说明第3疗程后症状改善优于第1疗程。结论:电针疏波组在改善疼痛上优于密波组;第3疗程后,总体症状改善情况优于第1疗程。  相似文献   
70.
It has recently been suggested that the mechanism for lifting liquid from a bowl into the oral cavity during lapping is fundamentally different in cats and dogs: cats use adhesion of liquid to the tongue tip while dogs 'scoop' with their backwardly curled tongue. High-speed light videos and X-ray videos show that on the contrary, both cats and dogs use the mechanism of adhesion. Liquid is transported through the oral cavity to the oesophagus, against gravity, on the surface of the tongue as it is drawn upwards, then a tight contact between the tongue surface and palatal rugae traps liquid and prevents its falling out as the tongue is protruded. At least three cycles are needed for intraoral transport of liquid in the dog.  相似文献   
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