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1.
In this paper we analyze the fishing effort allocation of fishermen in the artisanal fisheries of the Turks and Caicos Islands (British West Indies). These fishermen use a free-diving technique to simultaneously exploit the local stocks of queen conch and spiny lobster. Using an integrated framework combining a set of analytical tools within a multi-disciplinary holistic approach, we attempt to identify the biological, economic, and social mechanisms which govern the fishermen's effort allocation between the two targeted stocks. The analysis shows that the seasonal dynamics of the whole system are essentially dictated by the very remunerative lobster fishery. Although this result tends to espouse the predictions of classical economic theory, a closer analysis reveals that the economic rationality approach does not entirely explain the observed fishermen behavior. Information from a series of socio-anthropological surveys shows that the fishermen's decision making is further influenced by collective and individual constraints related to the specific diving abilities required to operate in the two fisheries and by the socio-historico-cultural environment within which the fishing community has been evolving over the last century. 相似文献
2.
ABSTRACTLarge herds pose the risk of worsening human—cattle relationships by reducing human contact and thus increasing the risk of accidents. In a survey on 35 dairy farms in Switzerland and Germany, different aspects of human—cow relationships were investigated. The effects of size of herd compared to other factors are presented here. Size of herds in the study varied from eight to 92 cows. On 35 farms the behavior of stockpersons toward their cows was observed directly during milking; personality characteristics of stockpersons were obtained by self-report-inventories, and a questionnaire on management practices was completed. Cows' avoidance distances toward a person were measured, and the social behavior of herds was observed directly.Size of herd correlated significantly negatively with the percentage of cows with an avoidance distance of zero ( rs=-0.52, p≤0.01), but there was no correlation with the median of avoidance distances per herd. Concerning the behavior of stockpersons, size of herd showed a significant negative correlation with the intensity/quality of contact with the cows ( rs=-0.51, p≤0.05), and a slightly significant correlation with the total number of talking to/touching interactions with the cows in the milking parlor ( rs=-34, p≤0.05). Quality of handling was not affected by size of herd, but the ability of the stockpersons to identify cows ( rs=-0.59, p≤0.001), and the frequency of brushing cows decreased with increasing sizes of herd ( rs=-0.52, p≤0.01). In regression analysis, the influence of size of herd on the intensity/quality of contact (CON) was confirmed, but showed a much smaller effect than the personality or attitudes of the stockpersons. Additionally, size of herd had no effect on avoidance distances. This was due to the elimination of the effects of CON.The small influence of size of herd on human-animal relationship parameters was mediated by the intensity of contact with the cows, but is much less important compared to other factors, e.g. the personality and attitudes of stockpersons. Smaller herds facilitated good relationships between a stockperson and his/her cows, but good human—animal relationships were also possible in big herds, and were observed even in the biggest herd (92 cows). 相似文献
3.
Androgenesis is a form of uniparental reproduction leading to progenies inheriting only the paternal set of chromosomes. It has been achieved with variable success in a number of freshwater species and can be attained by artificial fertilization of genetically inactivated eggs following exposure to gamma (γ), X-ray or UV irradiation (haploid androgenesis) and by restoration of diploidy by suppression of mitosis using a pressure or thermal shock. The conditions for the genetic inactivation of the maternal genome in the European sea bass ( Dicentrarchus labrax L.) were explored using different combinations of UV irradiation levels and durations. UV treatments significantly affected embryo survival and generated a wide range of developmental abnormalities. Despite the wide range of UV doses tested (from 7.2 to 720 mJ.cm −2), only one dose (60 mJ.cm −2.min −1 with 1 min irradiation) resulted in a small percentage (14%) of haploid larvae at hatching in the initial trials as verified by flow cytometry. Microsatellite marker analyses of three further batches of larvae produced by using this UV treatment showed a majority of larvae with variable levels of paternal and maternal contributions and only one larva displaying pure paternal inheritance. The results are discussed also in the context of an assessment of the UV-absorbance characteristics of egg extracts in this species that revealed the presence of gadusol, a compound structurally related to mycosporine-like amino acids (MAAs) with known UV-screening properties. 相似文献
4.
Ocean acidification, the progressive change in ocean chemistry caused by uptake of atmospheric CO 2, is likely to affect some marine resources negatively, including shellfish. The Atlantic sea scallop ( Placopecten magellanicus) supports one of the most economically important single-species commercial fisheries in the United States. Careful management appears to be the most powerful short-term factor affecting scallop populations, but in the coming decades scallops will be increasingly influenced by global environmental changes such as ocean warming and ocean acidification. In this paper, we describe an integrated assessment model (IAM) that numerically simulates oceanographic, population dynamic, and socioeconomic relationships for the U.S. commercial sea scallop fishery. Our primary goal is to enrich resource management deliberations by offering both short- and long-term insight into the system and generating detailed policy-relevant information about the relative effects of ocean acidification, temperature rise, fishing pressure, and socioeconomic factors on the fishery using a simplified model system. Starting with relationships and data used now for sea scallop fishery management, the model adds socioeconomic decision making based on static economic theory and includes ocean biogeochemical change resulting from CO 2 emissions. The model skillfully reproduces scallop population dynamics, market dynamics, and seawater carbonate chemistry since 2000. It indicates sea scallop harvests could decline substantially by 2050 under RCP 8.5 CO 2 emissions and current harvest rules, assuming that ocean acidification affects P. magellanicus by decreasing recruitment and slowing growth, and that ocean warming increases growth. Future work will explore different economic and management scenarios and test how potential impacts of ocean acidification on other scallop biological parameters may influence the social-ecological system. Future empirical work on the effect of ocean acidification on sea scallops is also needed. 相似文献
5.
Abstract
The complementary DNA coding for European sea bass somatolactin was expressed in the pET-3a bacteria expression vector. The
recombinant somatolactin (rbSL) was purified by size exclusion chromatography, and 95% of the protein remained in the oxidized
form with negligible aggregation over prolonged cold storage. The identity of the recombinant protein was demonstrated by
Western blotting with a rabbit polyclonal antibody against gilthead sea bream somatolactin. The same antibody was utilized
in a radioimmunoassay procedure, using rbSL as standard and radioiodinated tracer. Curve displacements of pituitary and plasma
samples paralleled the rbSL standard, and the midrange of the assay (8 ng/ml) was low enough to measure in a consistent manner
the circulating SL concentration. To assess biological activity a single dose of rbSL (0.1 μg/g of body mass) was administered
to juvenile gilthead sea bream by intraperitioneal injection. In comparison with saline-treated fish, rbSL did not modify
the circulating amount of insulin-like growth factor I, whereas a 50% increase was found with the same dose of recombinant
trout growth hormone (rtGH). Hormone treatment did not modify nitrogen-ammonia excretion, but both rbSL and rtGH increased
carbon dioxide output and oxygen uptake, which in turn decreased the respiratory quotient (CO 2 output per O 2 uptake). This pattern of gas exchange suggests the enhancement of lipid catabolism, which is consistent with the observation
that both hormones were able to inhibit the hepatic activity of acetyl–coenzyme A carboxylase. These new insights provide
direct evidence for the involvement of fish somatolactin in energy homeostasis, which may serve to maintain the lipolytic
tonus in different physiologic states. 相似文献
6.
A calcium-activated neutral cysteine protease was purified to homogeneity from Dicentrarchus labrax white muscle using three steps: hydrophobic interaction, anion exchange, and gel filtration chromatographies. The purified
enzyme showed a native molecular weight of 124 kDa with an oligomeric structure (large subunit of 80 kDa and small subunit
of 24 kDa). It has been classified as a milli-calpain from its calcium sensitivity. Activity was maximal at pH 7.0, 24°C in
Tris buffer without NaCl as determined by means of a two-level experimental design and response surface methodology. Sea bass
calpain is neither glycosylated nor phosphorylated and shared some common cleavage specificities and activation and autolysis
mechanisms with other typical mammalian or invertebrates calpains. Calcium-induced activation and autolysis of calpain has
been characterized together with the effect of the strontium cation acting as a calcium analog. On the basis of its in vitro
properties, the contribution of the sea bass milli-calpain to the process of postmortem deterioration of fish muscle is discussed,
even though further information such as in vivo regulation or in vitro effects on myofibrils is required.
Received March 1, 2001; accepted July 9, 2001. 相似文献
8.
A long-term epidemiological study of Cryptosporidium molnari in aquacultured European sea bass (ESB) and gilthead sea bream (GSB) was performed in different types of facilities on the Atlantic, Cantabric, and Mediterranean coasts. Four types of studies were carried out. In study A, fish raised from juveniles to marketable size (ongrowing stage) were periodically sampled in three different types of cultures. Studies B and C focused on hatchery and nursery facilities. In study D, occasional samplings were performed during mortality or morbidity outbreaks. As a general trend, C. molnari was more prevalent in GSB than in ESB. Data on the distribution pattern of C. molnari in total sampled GSB (studies A, B, and D) had a variance higher than the mean (overdispersion). In GSB (study A), the type of ongrowing system (sea cages, earth ponds, or indoor tanks) was found to have no significant effect. There was a significant relationship between the presence of the parasite and both fish weight and season. The highest infection values were recorded in spring. Prevalence and intensity had convex weight profiles, with a peak in 30- to 100-g fish. In study D, the prevalence of infection was higher in fish recently introduced in sea cages and in preongrowing systems. In studies B and C, fish were almost never infected before entering the postlarval and nursery facilities. The parasite seems to enter the host mainly through the water in production steps with less stringent water treatment. Recirculation systems and fish cannibalism could contribute to oocyst concentration and dispersion in aquaculture facilities. 相似文献
9.
Shared representations, emotion comprehension, and emotion regulation constitute the basic macro components of social empathy. The present study integrated two different measures of empathic behavior in a social context: verbal self-report measures (empathic response, emotional involvement and emotional significance, and valence), and autonomic responses (facial expression-corrugator supercilii and zygomaticus major muscle-, SCR-skin conductance-, and HR-heart rate-). Participants (N?=?thirty-five) were presented with different interpersonal scene types (cooperation, non-cooperation, conflict, indifference). Different empathic sensitivity to these interpersonal situations was verified, since self-rating on empathy, emotional involvement and valence varied as a function of interpersonal context. Situation rated as more empathically significant were considered also as the most positive (cooperation) and negative (non cooperation and conflictual) and emotionally significant (high emotional significance of the scenes) in comparison with neutral scenes. Nevertheless, subjective empathic response and personal emotional involvement were found to be dissociated measures in non-cooperative condition. On the autonomic level, facial mimicry was linked to and coherent with the empathic response in cooperative, non-cooperative and conflictual conditions, whereas SCR and HR were increased only in response to cooperative and conflictual situation, rated as more involving by the subject. The convergence of these multidimensional measures was discussed: empirical evidences are far from able to warrant claims that processes of emotional contagion and simulation provide the sole, primary important way by which we come to know what others are feeling. 相似文献
10.
ObjectivesTo assess the impact of a standardized pre-operative telephone checklist on the rate of late cancellations of ambulatory surgery (AMBUPROG trial). DesignMulticenter, two-arm, parallel-group, open-label randomized controlled trial. Setting11 university hospital ambulatory surgery units in Paris, France. ParticipantsPatients scheduled for ambulatory surgery and able to be reached by telephone. InterventionA 7-item checklist designed to prevent late cancellation, available in five languages and two versions (for children and adults), was administered between 7 and 3 days before the planned date of surgery, by an automated phone system or a research assistant. The control group received standard management alone. Main Outcome MeasuresRate of cancellation on the day of surgery or the day before. ResultsThe study population comprised 3900 patients enrolled between November 2012 and September 2013: 1950 patients were randomized to the checklist arm and 1950 patients to the control arm. The checklist was administered to 68.8% of patients in the intervention arm, 1002 by the automated phone system and 340 by a research assistant. The rate of late cancellation did not differ significantly between the checklist and control arms (109 (5.6%) vs. 113 (5.8%), adjusted odds ratio [95% confidence interval] = 0.91 [0.65–1.29], (p = 0.57)). Checklist administration revealed that 355 patients (28.0%) had not undergone tests ordered by the surgeon or anesthetist, and that 254 patients (20.0%) still had questions concerning the fasting state. ConclusionsA standardized pre-operative telephone checklist did not avoid late cancellations of ambulatory surgery but enabled us to identify several frequent causes. Trial RegistrationClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT01732159","term_id":"NCT01732159"}}NCT01732159 相似文献
12.
The artisanal fisheries of Ecuador operate within one of the most dynamic and productive marine ecosystems of the world. This study investigates the catch composition of the Ecuadorian artisanal fishery for large pelagic fishes, including aspects of its spatio-temporal dynamics. The analyses of this study are based on the most extensive dataset available to date for this fishery: a total of 106,963 trip-landing inspection records collected at its five principal ports during 2008 ‒ 2012. Ecuadorian artisanal fisheries remove a substantial amount of biomass from the upper trophic-level predatory fish community of the eastern tropical Pacific Ocean. It is estimated that at least 135 thousand metric tons (mt) (about 15.5 million fish) were landed in the five principal ports during the study period. The great novelty of Ecuadorian artisanal fisheries is the “oceanic-artisanal” fleet component, which consists of mother-ship ( nodriza) boats with their towed fiber-glass skiffs ( fibras) operating with pelagic longlines. This fleet has fully expanded into oceanic waters as far offshore as 100°W, west of the Galapagos Archipelago. It is estimated that nodriza operations produce as much as 80% of the total catches of the artisanal fishery. The remainder is produced by independent fibras operating in inshore waters with pelagic longlines and/or surface gillnets. A multivariate regression tree analysis was used to investigate spatio-environmental effects on the nodriza fleet (n = 6,821 trips). The catch species composition of the nodriza fleet is strongly influenced by the northwesterly circulation of the Humboldt Current along the coast of Peru and its associated cold waters masses. The target species and longline gear-type used by nodrizas change seasonally with the incursion of cool waters (< 25°C) from the south and offshore. During this season, dolphinfish ( Coryphaena hippurus) dominates the catches. However, in warmer waters, the fishery changes to tuna-billfish-shark longline gear and the catch composition becomes much more diverse. 相似文献
13.
The International Journal of Life Cycle Assessment - Numerous policy instruments are applied to agricultural production in the European Union (EU27). Implementing them may significantly influence... 相似文献
15.
Halophytes are plant species that tolerate high salinity levels. To adapt to these particular abiotic conditions, they develop multiple physiological, biochemical and molecular mechanisms, including the biosynthesis of osmolytes, enzymes and specialized metabolites. The French Flanders coast of the North Sea is an ideal environment for this kind of plant. Amaranthaceae is one of the most represented botanical families of halophytes present on this coast, with 15 species belonging to 7 genera, namely Atriplex, Beta, Halimione, Kali, Oxybasis, Salicornia and Suaeda. Some of these species are well known as wild edible plants, and some are used in traditional medicine. This review examines the chemistry of these species and their potential for human health. 相似文献
16.
ABSTRACT. A new myxosporean, Sphaerospora dicentrarchi n. sp., was found in numerous organs of wild and cultured sea bass ( Dicentrarchus labrax L.). It is distinguished from all previously reported Sphaerospora spp. by the shape and small size of the spores, location in the host and its geographical distribution. Prevalence of infection was 100% and 83.5% in wild and cultured fish, respectively. Outstanding ultrastructural features are the presence of a binucleate sporoplasm, valvogenic spheroidal structures and capsulogenic lipid inclusions. Other data concerning ultrastructure and sporogenesis are presented. 相似文献
17.
In 1981 a new epidemic of about two-dozen heterogeneous diseases began to strike non-randomly growing numbers of male homosexuals and mostly male intravenous drug users in the US and Europe. Assuming immunodeficiency as the common denominator the US Centers for Disease Control (CDC) termed the epidemic, AIDS, for acquired immunodeficiency syndrome. From 1981-1984 leading researchers including those from the CDC proposed that recreational drug use was the cause of AIDS, because of exact correlations and of drug-specific diseases. However, in 1984 US government researchers proposed that a virus, now termed human immunodeficiency virus (HIV), is the cause of the non-random epidemics of the US and Europe but also of a new, sexually random epidemic in Africa. The virus-AIDS hypothesis was instantly accepted, but it is burdened with numerous paradoxes, none of which could be resolved by 2003: Why is there no HIV in most AIDS patients, only antibodies against it? Why would HIV take 10 years from infection to AIDS? Why is AIDS not self-limiting via antiviral immunity? Why is there no vaccine against AIDS? Why is AIDS in the US and Europe not random like other viral epidemics? Why did AIDS not rise and then decline exponentially owing to antiviral immunity like all other viral epidemics? Why is AIDS not contagious? Why would only HIV carriers get AIDS who use either recreational or anti-HIV drugs or are subject to malnutrition? Why is the mortality of HIV-antibody-positives treated with anti-HIV drugs 7–9%, but that of all (mostly untreated) HIV-positives globally is only 1–4%? Here we propose that AIDS is a collection of chemical epidemics, caused by recreational drugs, anti-HIV drugs, and malnutrition. According to this hypothesis AIDS is not contagious, not immunogenic, not treatable by vaccines or antiviral drugs, and HIV is just a passenger virus. The hypothesis explains why AIDS epidemics strike non-randomly if caused by drugs and randomly if caused by malnutrition, why they manifest in drug- and malnutrition-specific diseases, and why they are not self-limiting via anti-viral immunity. The hypothesis predicts AIDS prevention by adequate nutrition and abstaining from drugs, and even cures by treating AIDS diseases with proven medications. 相似文献
18.
The various techniques in common use for conservation and restorationof depleted sea turtle populations are reviewed, namely: banninginternational commerce; operating artificial hatcheries, bothin the natural beach environment and in styrofoam and othertypes of incubators; "head-starting" of hatchlings in captivity;protection of nesting females by means of beach patrols; andtranslocation of eggs or hatchlings to distant areas from whichturtles have been extirpated or to which it is desired to introducenew colonies. The difficulties of monitoring the results ofall of these techniques are discussed, and potential dangersor disadvantages of each approach are reviewed. It is concludedthat, until unequivocal data become available, turtle conservationistsshould continue to pursue common sense or logically sound restorationprograms, but should constantly re-evaluate their actions inthe light of the latest available knowledge and modify or desistfrom current approaches as necessary. 相似文献
19.
Low levels of pharmaceuticals have been detected in many countries in surface waters. As a wide range of pharmaceuticals can reach aquatic environments, a selection of molecules to survey is the first step before implementing a monitoring program. We used a simple equation to calculate Predicted Environmental Concentrations (PECs), adapted from the European Medicine Agency model used for the Environmental Risk Assessment (ERA) of human pharmaceutical. Excretion fractions for pharmaceuticals were determined for 76 compounds. Using year 2004 French drug consumption data, we determined aquatic PECs for 112 parent molecules and several metabolites. Considering excretion fractions of pharmaceuticals can lead to drastically reduce predicted concentrations reaching the aquatic environment and help to target environmentally relevant pharmaceuticals and metabolites. Calculated PECs using the described methodology are consistent with French field measurements. The simple model for calculating PECs can be used as a valuable estimation of the exposure. Risk quotient ratios were also calculated. Due to the lack of ecotoxicological data, the use of PEC/PNEC ratios is not enough informative to prioritize pharmaceuticals likely to pose a risk for surface waters. Alternative ways to prioritize risk to pharmaceuticals, combining PEC, pharmacological, and ecotoxicological data available from the literature, should be implemented. 相似文献
20.
This article proposes an integrated Health Impact Assessment/Strategic Environmental Assessment (HIA/SEA) framework that can be applied to fishery products regulations in Taiwan Strait. In recent years, many studies with regards to organochlorine pesticides (OCPs), especially DDT and its derivatives, in Taiwan's environment and aquatic biota indicated that DDT, DDD, and DDE in seafood, especially oysters, in the Kinmen, Manchu area near China's Fu-Tzien Province, had relatively high concentrations. It was discussed that this may be caused by distribution of OCPs in China's vicinity. In this study, the concentration of DDT, DDD, and DDE reported by many researchers in the last two decades were compared and analyzed. The concentrations of these three chemicals were found to be as high as hundreds of ng/g-dw in seafood produced in Kimmen and Machu near China, whereas those for seafood caught in Taiwan's coastal areas were not significant. The need for trade agreements or regulations on fishery was then discussed. According to the viewpoints of health and environmental sustainability, HIA methodologies were incorporated in the SEA to help identify and analyze the potential impacts on human health caused by OCPs in seafood consumed in Taiwan, which may be caused by the lack of trade regulation mechanisms between Taiwan and China. The integrated HIA-SEA framework for fishery trade agreements or regulations in Taiwan was thus proposed and the procedures were discussed. It is anticipated that the health of Taiwan's residents can be protected through implementing this and the human health perspective can be emphasized in the HIA-SEA procedures. 相似文献
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