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21.
BRYAN D. WATTS GLENN D. THERRES MITCHELL A. BYRD 《The Journal of wildlife management》2008,72(1):152-158
Abstract We conducted annual aerial surveys throughout the tidal reach of the Chesapeake Bay, USA, between 1977 and 2001 to estimate population size and reproductive performance for bald eagles (Haliaeetus leucocephalus). The population increased exponentially from 73 to 601 pairs with an average doubling time of 8.2 years. Annual population increase was highly variable and exhibited no indication of any systematic decline. A total of 7,590 chicks were produced from 5,685 breeding attempts during this period. The population has exhibited tremendous forward momentum such that >50% of young produced over the 25-year period were produced in the last 6 years. Rapid population growth may reflect the combined benefits of eliminating persistent biocides and active territory management. Reproductive rate along with associated success rate and average brood size increased throughout the study period. Average reproductive rate (chicks/breeding attempt) increased from 0.82 during the first 5 years of the survey to 1.50 during the last 5 years. Average success rate increased from 54.4% to >80.0% during the same time periods. The overall population will likely reach saturation within the next decade. The availability of undeveloped waterfront property has become the dominant limiting factor for bald eagles in the Chesapeake Bay. Maintaining the eagle population in the face of a rapidly expanding human population will continue to be the greatest challenge faced by wildlife biologists. 相似文献
22.
目的:探讨血流阻断的缺血预处理技术在肝癌切除术中的临床应用价值。方法:选取2010年4月至2013年7月我院收治的96名原发性肝癌并采用肝脏部分切除术进行治疗的患者,将患者随机分为观察组和对照组,每组各48例,观察组在肝脏部分切除术阻断肝门血流前先分别给予1个5 min缺血和再灌注的处理。对照组不采取任何干预措施。术前、术后1天、3天、7天时分别进行生化检查,并于术前及术后1h对Fas-mRNA表达、Caspasc-3活性及AI进行测定,观察记录患者术后的并发症情况、手术时间、术中出血量以及住院时间。结果:术后1天、3天、7天时两组间的AST、ALT、TBIL等生化指标的含量情况相比,观察组均显著优于对照组(P0.05);术后l d,两组患者ALB均有不同程度的降低,对照组低于观察组(P0.05);术后住院时间观察组为13.28±3.85天,对照组为19.48±4.92天,观察组明显低于对照组(P0.05);术后1h,两组患者的Fas-mRNA表达、Caspasc-3活性相比于阻断前均显著提高,但观察组提高幅度明显低于对照组,差异有统计学意义(P0.05);两组阻断前均未见肝细胞凋亡,术后l h时,两组组均可见肝细胞凋亡,且对照组明显高于观察组组(P0.05)。结论:血流阻断的缺血预处理技术具有操作简便、副作用小的重要特点,应用于肝癌切除术中在保护肝功能方面具有显著的优势。 相似文献
23.
《Somatosensory & motor research》2013,30(1):21-31
An investigation was made of the capacities of humans to detect, by actively touching with the fingertip, the presence of a single, small asperity on a very smooth background. The asperity consisted of either a raised dot having a diameter of 602, 231, or 40 μum, or an edge, each etched into a silicon wafer using the methods of contact photolithography. The height of each dot or edge was varied and the subject was asked to make a forced choice on each test trial as to which of two wafers, one of which was blank, contained the asperity. The mean detection threshold, or minimal height of asperity corresponding to a d' of 1.35, was lowest for edges (0.85 ± 0.22 μm, SD) and increased with decreases in the diameter of dot from 1.09 ± 0.19 μm for a diameter of 602 μm to 2.94 ± 1.19 μm and 5.97 ± 2.02 μm for diameters of 231 μm and 40 μm, respectively. The type of skin displacement required for the detection of these small asperities was believed to be a local lateral deformation of the papillary ridges. 相似文献
24.
An Improved CARV Process for Bioethanol Production from a Mixture of Sugar Beet Mash and Potato Mash
《Bioscience, biotechnology, and biochemistry》2013,77(3):602-604
A mixed mash of sugar beet roots and potato tubers with a sugar concentration of 23.7% w/v was used as a feedstock for bioethanol production. Enzymatic digestion successfully reduced the viscosity of the mixture, enabling subsequent heat pretreatment for liquefaction/sterilization. An energy-consuming thick juice preparation from sugar beet for concentration and sterilization was omitted in this new process. 相似文献
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ThuyTien Nguyen I. Ricardo Argueta-Morales Stephen Guimond William Clark Andres Ceballos Ruben Osorio 《Computer methods in biomechanics and biomedical engineering》2016,19(7):789-799
Stroke is the most devastating complication after ventricular assist device (VAD) implantation with a 19% incidence and 65% mortality in the pediatric population. Current pediatric VAD technology and anticoagulation strategies alone are suboptimal. VAD implantation assisted by computational methods (CFD) may contribute reducing the risk of cerebral embolization. Representative three-dimensional aortic arch models of an infant and a child were generated. An 8 mm VAD outflow-graft (VAD-OG) anastomosed to the aorta was rendered and CFD was applied to study blood flow patterns. Particle tracks, originating in the VAD, were computed with a Lagrangian phase model and the percentage of particles entering the cerebral vessels was calculated. Eight implantation configurations (infant = 5 and child = 3) and 5 particle sizes (0.5, 1, 2, 3, and 4 mm) were considered. For the infant model, percentage of particles entering the cerebral vessels ranged from 15% for a VAD-OG anastomosed at 90° to the aorta, to 31% for 30° VAD-OG anastomosis (overall percentages: X2 = 10,852, p < 0.0001). For the child model, cerebral embolization ranged from 9% for the 30° VAD-OG anastomosis to 15% for the 60° anastomosis (overall percentages: χ2 = 10,323, p < 0.0001). Using detailed CFD calculations, we demonstrate that the risk of stroke depends significantly on the VAD implantation geometry. In turn, the risk probably depends on patient-specific anatomy. CFD can be used to optimize VAD implantation geometry to minimize stroke risk. 相似文献
28.
Malika Virah-Sawmy Katherine J. Willis Lindsey Gillson 《Global Ecology and Biogeography》2009,18(1):98-110
Aim Coastal biodiversity hotspots are globally threatened by sea‐level rise. As such it is important to understand how ecosystems resist, respond and adapt to sea‐level rise. Using pollen, geochemistry, charcoal and diatom records in conjunction with previously published palaeoclimatic records, we investigated the mechanism, interactions and ecosystem response and resilience of Madagascar's littoral forest to late Holocene sea‐level rise. Location Sediment sequences were collected along the south‐east coast of Madagascar in two adjacent habitats in Mandena; the highly diverse littoral forest fragment and species‐poor Erica‐matrix. Methods We used a multi‐proxy approach to investigate the relative influence of environmental changes on the littoral ecosystem. We reconstructed past vegetation and fire dynamics over the past 6500 years at two sites in the littoral forest using fossil pollen and macrofossil charcoal contained in sedimentary sequences. Alongside these records we reconstructed past marine transgressions from the same sedimentary sequences using geochemical analyses, and a salinity and drought index through the analysis of fossil diatoms. Results Our findings indicated that it was the synergistic effect of sea‐level rise coupled with rainfall deficits that triggered a threshold event with a switch from two types of littoral forest (an open Uapaca forest and a closed littoral forest fragment) to an Erica–Myrica heath/grassland occurring in approximately less than 100 years. Resilience to sea‐level rise differed in the two adjacent habitats, suggesting that the littoral forest fragment was more resilient to the impacts of sea‐level change and aridity than the open Uapaca woodland. Conclusions We demonstrated that the littoral ecosystem was influenced by late Holocene sea‐level rise and climatic desiccation. While climate change‐integrated conservation strategies address the effects of climate change on species distribution and dispersal, our work suggests that more attention should be paid to the impacts of interactive climatic variables that affect ecosystem thresholds. 相似文献
29.
《Revista espa?ola de geriatría y gerontología》2020,55(1):11-17
Background and objectiveThe aim of this study was to determine the clinical and functional outcomes of patients discharged to nursing homes after a hip fracture.MethodsThe study included all patients admitted to a group of nursing homes after a hip fracture in 2016. A geriatric assessment protocol was applied, and patients were treated with a specific protocol for 90 days. They were assessed for nutritional status (Mini-Nutritional Assessment and Body Mass Index), pain (Visual Analogue Scale, and the PAINAD Scale), the presence of pressure ulcers, blood test (D vitamin, haemoglobin, proteins), and functional status (Barthel index and Functional Assessment Categories).ResultsOut of a total of 175 patients, 116 (75%) met the inclusion criteria. The mean age was 84.9 years old (±6.7 SD), and 91 (78.4%) were women. At admission, 73.8% of 65 residents had anaemia, 76.7% hypovitaminosis D, 88% malnutrition or «at risk of malnutrition», and 15.3% had pressure ulcers. After 90 days, the moderate-severe functional status (Barthel index < 60) was reduced from 90.4 to 39.6%, dependence due to gait from 97.3 to 36.1%, and moderate-severe pain from 88.9 to 14.4%. Most of the pressure ulcers healed (94.4%).ConclusionsPatients admitted to nursing homes after a hip fracture had poor clinical and functional status. This study shows that after 90 days from admission these patients had positive outcomes in terms of functionality, gait, pain control, and pressure ulcers healing. 相似文献
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