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81.
82.
In a resource-limited world, organisations attempting to reduce the impact of health or behaviour issues need to choose carefully how to allocate resources for the highest overall impact. However, such choices may not always be obvious. Which has the biggest impact? A large change to a small number of individuals, or a small change to a large number of individuals? The challenge is identifying the issues that have the greatest impact on the population so potential interventions can be prioritised. We addressed this by developing a score to quantify the impact of health conditions and behaviour problems in a population of working guide dogs using data from Guide Dogs, UK. The cumulative incidence of different issues was combined with information about their impact, in terms of reduction in working life, to create a work score. The work score was created at population-level to illustrate issues with the greatest impact on the population and to understand contributions of breeds or crossbreeds to the workforce. An individual work deficit score was also created and means of this score used to illustrate the impact on working life within a subgroup of the population such as a breed, or crossbreed generation. The work deficit scores showed that those removed for behavioural issues had a greater impact on the overall workforce than those removed for health reasons. Additionally trends over time illustrated the positive influence of interventions Guide Dogs have made to improve their workforce. Information highlighted by these scores is pertinent to the effort of Guide Dogs to ensure partnerships are lasting. Recognising that the scores developed here could be transferable to a wide variety of contexts and species, most notably human work force decisions; we discuss possible uses and adaptations such as reduction in lifespan, quality of life and yield in production animals. 相似文献
83.
Impacts of climate variability on tree demography in second growth tropical forests: the importance of regional context for predicting successional trajectories
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María Uriarte Naomi Schwartz Jennifer S. Powers Erika Marín‐Spiotta Wenying Liao Leland K. Werden 《Biotropica》2016,48(6):780-797
Naturally regenerating and restored second growth forests account for over 70% of tropical forest cover and provide key ecosystem services. Understanding climate change impacts on successional trajectories of these ecosystems is critical for developing effective large‐scale forest landscape restoration (FLR) programs. Differences in environmental conditions, species composition, dynamics, and landscape context from old growth forests may exacerbate climate impacts on second growth stands. We compile data from 112 studies on the effects of natural climate variability, including warming, droughts, fires, and cyclonic storms, on demography and dynamics of second growth forest trees and identify variation in forest responses across biomes, regions, and landscapes. Across studies, drought decreases tree growth, survival, and recruitment, particularly during early succession, but the effects of temperature remain unexplored. Shifts in the frequency and severity of disturbance alter successional trajectories and increase the extent of second growth forests. Vulnerability to climate extremes is generally inversely related to long‐term exposure, which varies with historical climate and biogeography. The majority of studies, however, have been conducted in the Neotropics hindering generalization. Effects of fire and cyclonic storms often lead to positive feedbacks, increasing vulnerability to climate extremes and subsequent disturbance. Fragmentation increases forests’ vulnerability to fires, wind, and drought, while land use and other human activities influence the frequency and intensity of fire, potentially retarding succession. Comparative studies of climate effects on tropical forest succession across biogeographic regions are required to forecast the response of tropical forest landscapes to future climates and to implement effective FLR policies and programs in these landscapes. 相似文献
84.
Badgers prefer cattle pasture but avoid cattle: implications for bovine tuberculosis control
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Rosie Woodroffe Christl A. Donnelly Cally Ham Seth Y. B. Jackson Kelly Moyes Kayna Chapman Naomi G. Stratton Samantha J. Cartwright 《Ecology letters》2016,19(10):1201-1208
Effective management of infectious disease relies upon understanding mechanisms of pathogen transmission. In particular, while models of disease dynamics usually assume transmission through direct contact, transmission through environmental contamination can cause different dynamics. We used Global Positioning System (GPS) collars and proximity‐sensing contact‐collars to explore opportunities for transmission of Mycobacterium bovis [causal agent of bovine tuberculosis] between cattle and badgers (Meles meles). Cattle pasture was badgers’ most preferred habitat. Nevertheless, although collared cattle spent 2914 collar‐nights in the home ranges of contact‐collared badgers, and 5380 collar‐nights in the home ranges of GPS‐collared badgers, we detected no direct contacts between the two species. Simultaneous GPS‐tracking revealed that badgers preferred land > 50 m from cattle. Very infrequent direct contact indicates that badger‐to‐cattle and cattle‐to‐badger M. bovis transmission may typically occur through contamination of the two species’ shared environment. This information should help to inform tuberculosis control by guiding both modelling and farm management. 相似文献
85.
Qu Wei-Min Huang Zhi-Li Mochizuki Takatoshi Eguchi Naomi Chen Jiang-Fan Schwarzschild Michael A. Fink Stephen J. Urade Yoshihiro Hayaishi Osamu 《Sleep and biological rhythms》2016,2(1):S55-S55
Sleep and Biological Rhythms - 相似文献
86.
Traditional ecological theory predicts that specialisation can promote speciation; hence, recently derived species are specialists. However, an alternative view is that new species have broad niches, which become narrower and specialised over time. Here, we test these hypotheses using avian brood parasites and three different measures of host specialisation. Brood parasites provide an ideal system in which to investigate the evolution of specialisation, because some exploit more than 40 host species and others specialise on only one. We find that young brood parasite species are smaller and specialise on a narrower range of host sizes, as expected, if specialisation is linked with the generation of new species. Moreover, we show that highly virulent parasites are more specialised, supporting findings in other host–parasite systems. Finally, we demonstrate that different measures of specialisation can lead to different conclusions, and specialisation indices should be designed taking into account the biology of each system. 相似文献
87.
Shutao Zheng Qing Liu Rong Ma Doudou Tan Tongxue Shen Xiao Zhang Xiaomei Lu 《Cell biology international》2019,43(6):634-641
KIAA1377 has been found to be linked with lymph node metastasis in esophageal squamous cell carcinoma (SCC) in our previous study; however, the regulation of KIAA1377 remains far from understood. Herein, to understand the regulation of KIAA1377 from the angle of microRNA (miRNA)–messenger RNA (mRNA) modulation in the setting of SCC cells, the basal level of KIAA1377 was determined by quantitative real‐time polymerase chain reaction (qRT‐PCR) and western blot analysis in KYSE‐150 and HeLa cells; biological roles of KIAA1377 contributing in the proliferation, migration, and invasion were evaluated using 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyl‐2H‐tetrazolium bromide (MTT), wound‐healing and Transwell assays, respectively, after KIAA1377 was knocked out mediated by the CRISPR‐Cas9 system. Bioinformatic prediction revealed that let‐7b‐5p was a putative miRNA regulating KIAA1377, which was ensuingly validated by the luciferase reporter assay; after which, variation of KIAA1377 expression was further verified by qRT‐PCR and western blot analysis. Moreover, the biological roles of let‐7b‐5p in proliferation, migration, and invasion of KYSE‐150 and HeLa cells were also evaluated. It was exhibited that KIAA1377 was able to promote the proliferation and motility of both KYSE‐150 and HeLa cells, which can be reverted by re‐expression of let‐7b‐5p. The luciferase reporter assay verified that let‐7b‐5p can diametrically target KIAA1377. Collectively, our data demonstrated that let‐7b‐5p can directly but negatively regulate KIAA1377 in SCC cell lines, Ecal109, and HeLa cells. 相似文献
88.
Jelena Petrovic Yeqiao Zhou Maria Fasolino Naomi Goldman Gregory W. Schwartz Maxwell R. Mumbach Son C. Nguyen Kelly S. Rome Yogev Sela Zachary Zapataro Stephen C. Blacklow Michael J. Kruhlak Junwei Shi Jon C. Aster Eric F. Joyce Shawn C. Little Golnaz Vahedi Warren S. Pear Robert B. Faryabi 《Molecular cell》2019,73(6):1174-1190.e12
89.
90.
The aorta-gonad-mesonephros (AGM) region is a primary source of definitive hematopoietic cells in the midgestation mouse embryo. In cultures of dispersed AGM regions, adherent cells containing endothelial cells are observed first, and then non-adherent hematopoietic cells are produced. Here we report on the characterization of hematopoietic cells that emerge in the AGM culture. Based on the expression profiles of CD45 and c-Kit, we defined three cell populations: CD45(low) c-Kit(+) cells that had the ability to form hematopoietic cell colonies in methylcellulose media and in co-cultures with stromal cells; CD45(low) c-Kit(-) cells that showed a granulocyte morphology; CD45(high) c-Kit(low/-) that exhibited a macrophage morphology. In co-cultures of OP9 stromal cells and freshly prepared AGM cultures, CD45(low) c-Kit(+) cells from the AGM culture had the abilities to reproduce CD45(low) c-Kit(+) cells and differentiate into CD45(low) c-Kit(-) and CD45(high) c-Kit(low/-) cells, whereas CD45(low) c-Kit(-) and CD45(high) c-Kit(low/-) did not produce CD45(low) c-Kit(+) cells. Furthermore, CD45(low) c-Kit(+) cells displayed a long-term repopulating activity in adult hematopoietic tissue when transplanted into the liver of irradiated newborn mice. These results indicate that CD45(low) c-Kit(+) cells from the AGM culture have the potential to reconstitute multi-lineage hematopoietic cells. 相似文献