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71.
A contemporary issue of major concern is the millions of people fleeing homelands owing to political and socioeconomic challenges and seeking assistance elsewhere throughout the world. An effective response to this crisis includes support models that meet the various needs of refugee populations. In the complex system of humanitarian action, aid workers, among a multiplicity of actors, are the most important assets. This study utilised an inclusion–exclusion theoretical lens to examine the impact of their workplace experiences on activities in the context of the refugee crisis in Lebanon. In-depth interviews were held with 36 humanitarian practitioners, representing five international organisations that are involved in refugee aid programmes in the country. The study led to a new understanding of the link between inclusion and exclusion and the effectiveness of the humanitarian response to emergencies. In addition, it yielded new insights into apprehension about the national–international divide and its consequences for humanitarian assistance.  相似文献   
72.
We used acoustic telemetry to examine the small-scale movement patterns of yellowfin tuna (Thunnus albacares) in the California Bight at the northern extent of their range. Oceanographic profiles of temperature, oxygen, currents and fluorometry were used to determine the relationship between movements and environmental features. Three yellowfin tuna (8 to 16 kg) were tracked for 2 to 3 d. All three fish spent the majority of their time above the thermocline (18 to 45 m in depth) in water temperatures >17.5 °C. In the California Bight, yellowfin tuna have a limited vertical distribution due to the restriction imposed by temperature. The three fish made periodic short dives below the thermocline (60 to 80 m), encountering cooler temperatures (>11 °C). When swimming in northern latitudes, the depth of the mixed layer largely defines the spatial distribution of yellowfin tuna within the water column. Yellowfin prefer to spend most of their time just above the top of the thermocline. Oxygen profiles indicated that the tunas encountered oceanic water masses that ranged most often from 6.8 to 8.6 mg O2 l−1, indicating no limitation due to oxygen concentrations. The yellowfin tuna traveled at speeds ranging from 0.46 to 0.90 m s−1 (0.9 to 1.8 knots h−1) and frequently exhibited an oscillatory diving pattern previously suggested to be a possible strategy for conserving energy during swimming. Received: 14 February 1997 / Accepted: 14 April 1997  相似文献   
73.
74.
Following initial experiments presented elsewhere (2IOPS), the bacterial degradation of two vegetable oils was investigated in some detail. the number of aerobic and anaerobic heterotrophic bacteria, oil degrading and sulphate reducing bacteria were quantified during simulated spills on a salt marsh. the sediment fatty acid composition was also studied using GC-MS analysis. Degradation of linseed and sunflower oils was concomitant with an increase in the numbers of aerobic and anaerobic bacteria. Fatty acids analysis revealed preferential degradation of the principal components of the oils (18:3ω3 for linseed oil and 18:2ω6 for sunflower oil). the presence of several isomers of the usual polyunsaturated fatty acids was also detected. the identification of some of these new fatty acids has been carried out. Possible pathways of degradation of these vegetable oils are suggested.  相似文献   
75.
This study presents an evaluation of a participatory bird census (PBC) project that has been administered to coffee farmers in Colombia. Our objectives were (1) to evaluate the effect of the PBC project on conservation knowledge, attitudes, and behaviors of coffee farmers and (2) to learn about the barriers farmers perceive toward adopting conservation practices. We conducted 261 interviews on four groups to control for the effects of involvement with an environmental coffee certification program (Rainforest Alliance??RA) and the PBC project. The four groups were (1) non-PBC participant, non-RA certified; (2) PBC participant, non-RA certified; (3) non-PBC participant, RA certified; and (4) PBC participant, RA certified. PBC participant/RA and PBC participant/non-RA were more knowledgeable about migratory and threatened birds. PBC participant/RA, PBC participant/non-RA, and non-PBC participant/RA groups believed they had the skills to perform bird conservation practices on their farms. A majority of respondents indicated that they were performing bird conservation practices and had positive attitudes toward birds. Farmers believed that lack of environmental awareness and lack of knowledge were the main barriers to perform bird conservation practices. Evaluating participatory programs with Colombian farmers can reveal environmental literacy improvements, but self-reported surveys may not be adequate to ascertain attitude changes and adoption of conservation practices. Direct observations on individual farms would be required to determine the impacts on such outreach efforts. Bird conservation seems popular with Colombian coffee farmers, and outreach programs that give detailed biodiversity management information could help aid bird conservation efforts on coffee farms.  相似文献   
76.
Multiplex acoustic transmitters were used to monitor the depth, swimming speeds, body temperature and water temperature preference of six blue marlin, Makaira nigricans (Lacépède), near the Hawaiian islands in July and August 1989. The blue marlin ranged in size from 60 to 220 kg and were tracked for 1 to 5 d. All of the fish moved away from the point of capture and were followed up to 253 km from the island of Hawaii. The blue marlin tracked remained in the top 200 m of the water column, spending half the time in the upper 10 m, and rarely ventured below the thermocline. In the nearsurface waters the temperature was uniformly warm (25 to 27°C). The coldest water temperature, 17°C, was encountered on the deepest descent recorded (209 m). Depth changes occurred rapidly and excursions below 10 m were usually less than 60 min in duration. Muscle temperature was similar to water temperature except for a 2°C elevation in muscle temperature observed at the beginning of tracking one individual. This initial rise in body temperature was associated with the anaerobic muscle activity during capture and is an indication of the physiological stress involved in capture.  相似文献   
77.
ABSTRACT: The production of a documentary video in a graduate seminar offers advantages over the traditional term paper. These advantages derive from the nature of the videotape medium. The most distinct difference between a written document and a video production is the use of the video camera to record events. In using the camera, the student is required to become involved both in front of the video camera, for example, as an interviewer, and behind the camera as a camera operator. Next, as an editor, the student is required to review the events that she/he has taped for inclusion in the final product. By participating in these three roles, the student has the opportunity to learn interviewing skills while interacting with professionals in the field, to learn videotaping skills, and to see him/herself as he/she appears to others. The student can use the video feedback to improve his/her professional presentation; posture, dress, gestures, speech, and facial expressions all have an impact on how we are perceived by others. Additionally, the painstaking process of reviewing the taped material leads to an intimate knowledge of the topic, and the process of choosing portions out of entire interviews hones the ability to select the crucial or central themes and ideas from any discussion. Finally, the power of video lies in its ability to communicate information to a wide audience. Although the nature of video for the general public does not permit highly detailed or rigorous coverage of any topic, it is a major source of information. Accordingly, video is an important tool that can be used to inform the public about the importance of wise water resource management.  相似文献   
78.
Polychlorinated biphenyls (PCBs) are of environmental concern due to their toxic nature. Ionizing radiation has been suggested as a means to remediate PCB-contaminated samples in complex matrices. A set of experiments was performed to qualitatively and quantitatively determine the aromatic degradation products of 2-monochlorobiphenyl (2-MCB) in an aqueous system exposed to ionizing radiation. The degradation of 2-MCB was observed in aqueous samples that were exposed to radiation from a linear accelerator electron beam source. Analytical measurements performed by liquid chromatography (LC) equipped with an ultraviolet (UV) detector revealed that biphenyl, o-hydroxybiphenyl, p-hydroxybiphenyl, phenol, chlorobenzene, and other unidentified products were created after 2-MCB irradiation. These results suggest that sensitive and selective analytical methods will be required to account for all degradation products during ionizing radiation of aqueous PCB-contaminated samples.  相似文献   
79.
The analysis of mitochondrial DNA in loggerhead sea turtles (Caretta caretta) from eight foraging grounds in the Mediterranean and the adjoining Atlantic revealed deep genetic structuring within the western Mediterranean. As a consequence, the foraging grounds off the North-African coast and the Gimnesies Islands are shown to be inhabited mainly by turtles of the Atlantic stocks, whereas the foraging grounds off the European shore of the western Mediterranean are shown to be inhabited mainly by turtles from the eastern Mediterranean rookeries. This structuring is explained by the pattern of sea surface currents and water masses and suggests that immature loggerhead sea turtles entering the western Mediterranean from the Atlantic and the eastern Mediterranean remain linked to particular water masses, with a limited exchange of turtles between water masses. As the north of the western Mediterranean comprises mostly individuals from the highly endangered eastern Mediterranean rookeries, conservation plans should make it a priority to reduce the mortality caused by incidental by-catch in these areas.  相似文献   
80.
A novel transdisciplinary approach to investigate Global Change (GC) is presented. The approach rests on the decomposition of the intrigue dynamics of GC into patterns of civilization–nature interactions (syndromes) by an iterative scientific process of observations, data and system theoretical analyses, and modelling attempts. We illustrate the approach by a detailed analysis of the Sahel Syndrome, which describes the rural poverty driven overuse of natural resources. The investigation is performed by (i) identifying relevant symptoms and interlinkages which are characteristics for this pattern, and (ii) a qualitative model representing the internal dynamics of the essential flywheel. The geographical patchwork of the regions affected by the syndrome which is obtained by global data analysis, proves the high global relevance of this pattern. The qualitative model is employed for an evaluation of basic policy strategies debated in the context of rural poverty driven environmental degradation. It turns out that a mixed policy of combating poverty and introducing soil preserving agricultural techniques and practices is most promising to tackle the syndrome dynamics.  相似文献   
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