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41.
Evidence of farm-level synergies in mixed-farming systems in the Australian Wheat-Sheep Zone 总被引:1,自引:0,他引:1
Synergies are reported for mixed-enterprise farming systems in a benchmarking group in the Wheat-Sheep Zone in New South Wales, Australia. A stochastic input distance function is estimated and a measure of synergies is calculated, based on the second cross partial derivative of output variables in the distance function. Evidence is presented of strong synergies from complementarity between sheep and beef enterprises, sheep and crop enterprises, and beef and crop enterprises. 相似文献
42.
Milaja Nyknen Marie Louis Eileen Dillane Eric Alfonsi Simon Berrow Joanne O'Brien Andrew Brownlow Pablo Covelo Willy Dabin Rob Deaville Renaud de Stephanis Franois Gally Pauline Gauffier Simon N. Ingram Tamara Lucas Luca Mirimin Rod Penrose Emer Rogan Mnica A. Silva Benoit Simon‐Bouhet Oscar E. Gaggiotti 《水产资源保护:海洋与淡水生态系统》2019,29(Z1):197-211
43.
44.
Pauline Eadie 《Asia Pacific viewpoint》2019,60(1):94-107
After Typhoon Yolanda devastated the Philippines, ‘resilient’ was a term frequently used by the media, survivors, government officials and various other stakeholders in the city of Tacloban to describe those affected by the disaster. The focus of this article is therefore on how this term was articulated and experienced during this period. The analysis covers how resilience was discursively deployed to describe the condition of residents who were, in fact, often suffering from a double process of dispossession: once by the typhoon and once more by government policy and the inequitable distribution of relief goods and services due to the inadequacies of the disaster response. Despite these inadequacies, Tacloban was presented as ‘an exemplary centre’ of the post‐Typhoon Yolanda relief effort. I argue that the overarching rhetoric and strategies of resilience became rituals aimed at normalising modes of profit‐seeking and recreating the unequal socio‐economic status quo. These rituals occurred at multiple levels; however, the fortunes of Tacloban were indelibly intertwined with the political credibility and status pride of the Marcos/Romualdez family. I argue that ‘resilience’ is a complex, overused, manipulated and contested term and that a more transparent understanding of resilience for disaster relief and rehabilitation is needed. 相似文献
45.
This paper describes a modelling approach to the allocation of land as between forestry and agriculture in the context of hill and upland. The model can be used to examine objectively the outcome of some of the stated objectives and constraints concerned with integration. Examples in the use of the model are presented. 相似文献
46.
Yamaya Y Niizeki K Kim J Entin P Wagner H Wagner PD 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1429-1432
Two of 26 anesthetized dogs given the cardiac echo-enhancing agent Optison showed anaphylactoid responses (AR) related to the human albumin component of this agent. The episodes of AR were self-limited, and could be reproduced by human albumin injection alone. Gas exchange was maintained by mechanical ventilation and 5 cm H(2)O PEEP, and dispersion of ventilation remained normal during AR despite severe hypotension. We suggest that: (1) pre-screening by measuring blood pressure response to intravenous injection of small doses of Optison, and (2) availability of access to the airway in addition to emergency agents may be prudent preventive measures when Optison is used in animals to enhance echocardiographic imaging. 相似文献
47.
Peter A. Burrough John P. Wilson Pauline F.M. van Gaans Andrew J. Hansen 《Landscape Ecology》2001,16(6):523-546
Previous attempts to quantify topographic controls on vegetation have often been frustrated by issues concerning the number of variables of interest and the tendency of classification methods to create discrete classes though species have overlapping property sets (niches). Methods of fuzzy k-means classification have been used to address class overlap in ecological and geographical data but previously their usefulness has been limited when data sets are large or include artefacts that may occur through the derivation of topo-climatic attributes from gridded digital elevation models. This paper presents ways to overcome these limitations using GIS, spatial sampling methods, fuzzy k-means classification, and statistical modelling of the derived stream topology. Using data from a ca. 3600 km2 forested site in the Greater Yellowstone Area, we demonstrate the creation of meaningful, spatially coherent topo-climatic classes through a fuzzy k-means classification of topo-climatic data derived from 100 m gridded digital elevation models (DEMs); these classes were successfully extrapolated to adjacent areas covering a total of ca. 10000 km2. Independently derived land cover data and middle infrared corrected Landsat TM derived estimates of Normalised Difference Vegetation Index (M_NDVI) at 575 independently sampled sites were used to evaluate the topo-climatic classes and test their extrapolation to the larger area. Relations between topo-climatic classes and land cover were tested by 2 analysis which demonstrated strong associations between topo-climatic class and 11 of the 15 cover classes. Relations between M_NDVI and topo-climatic classes proved to be stronger than relations between M_NDVI and the independent cover classes. We conclude that the fuzzy k-means procedure yields sensible and stable topo-climatic classes that can be used for the rapid mapping of large areas. The value of these methods for quantifying topographic controls on biodiversity and the strength of their relations with computed NDVI values warrant further investigation. 相似文献
48.
Pauline Gauthier Anne‐Pauline Bellanger Fabienne Bozon Quentin Lepiller Catherine Chirouze Philippe Marguet 《Zoonoses and public health》2020,67(2):193-197
International tourism is steadily increasing, with 15% of travellers reporting health problems when they come back. Animal bites represent 2% of consulting causes, of which 20% are due to monkey bites. The Monkey B virus (Macacine alphaherpesvirus 1) is an alphaherpesvirus (Herpesviridae, genus Simplexvirus) enzootic in macaques (Genus Macaca). Zoonotic infections with the Monkey B virus following exposure to macaques are exceptionally rare, but can cause fatal encephalomyelitis in humans. An observational survey was undertaken in 2018 to assess the practice of French health professionals regarding infection risk after monkey bites. French health professionals practicing in vaccination and rabies centres were specifically targeted for this study. Standardized questionnaires were sent by email to a sample of French health professionals. They were asked to participate on a voluntary and anonymous basis. The questionnaires requested epidemiological details and included multiple‐choice questions about the infection management of monkey bites. The response rate was 33.5%. The frequency of monkey bites in 2017 was variable with a minority of centres managing more than 6 per year (12%), 46% managing 1–5 monkey bites and 42% none. Most of the monkey bites were described as occurring in South Asia at tourist sites, on naked upper limbs, shortly after the travellers arrived at their destination. Tetanus status verification, rabies post‐exposure prophylaxis and antibiotic therapy were said to be prescribed in most cases. Knowledge about the Monkey B virus was reported as scarce for 38% of the participants. The number of monkey bites managed per year per centre varied greatly but practices regarding infectious risk after monkey bites were generally homogeneous. The risk of Monkey B virus transmission did not readily come to mind in the differential diagnosis of infection risk for many French health professionals. 相似文献
49.
McNamara C Zinkernagel AS Macheboeuf P Cunningham MW Nizet V Ghosh P 《Science (New York, N.Y.)》2008,319(5868):1405-1408
Antigenically variable M proteins are major virulence factors and immunogens of the human pathogen group A Streptococcus (GAS). Here, we report the approximately 3 angstrom resolution structure of a GAS M1 fragment containing the regions responsible for eliciting type-specific, protective immunity and for binding fibrinogen, which promotes M1 proinflammatory and antiphagocytic functions. The structure revealed substantial irregularities and instabilities throughout the coiled coil of the M1 fragment. Similar structural irregularities occur in myosin and tropomyosin, explaining the patterns of cross-reactivity seen in autoimmune sequelae of GAS infection. Sequence idealization of a large segment of the M1 coiled coil enhanced stability but diminished fibrinogen binding, proinflammatory effects, and antibody cross-reactivity, whereas it left protective immunogenicity undiminished. Idealized M proteins appear to have promise as vaccine immunogens. 相似文献
50.
Anthony J. Conner Philippa J. Barrell Samantha J. Baldwin Annemarie S. Lokerse Pauline A. Cooper Astrid K. Erasmuson Jan-Peter Nap Jeanne M. E. Jacobs 《Euphytica》2007,154(3):341-353
The intragenic vector system involves identifying functional equivalents of vector components from the genome of a specific
crop species (or related species to which it can be hybridised) and using these DNA sequences to assemble vectors for transformation
of that plant species. This system offers an attractive alternative to current genetic engineering strategies where vectors
are based on DNA sequences that usually originate from bacteria. The construction of intragenic vectors enables the well-defined
genetic improvement of plants with all transferred DNA originating from within the gene pool already available to plant breeders.
In this manner genes can be introgressed into elite cultivars in a single step without linkage drag and without the incorporation
of foreign DNA. The resulting plants are non-transgenic, although they are derived using the tools of molecular biology and
plant transformation. The use of intragenic vectors for the transfer of genes from within the gene pools of crops may help
to alleviate some of the major public concerns over the deployment of GM crops in agriculture, notably the ethical issue associated
with the transfer of DNA across wide taxonomic boundaries. This paper reviews the progress toward the development and use
of intragenic vectors and the implications of their use for the genetic improvement of crops.
Dedicated to the late Hans Sandbrink for his enthusiasm in helping to develop intragenic vectors 相似文献