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Spatial and temporal variation in artisanal catches of dolphinfish Coryphaena hippurus off north‐eastern Brazil 下载免费PDF全文
The sampling of fish from the artisanal fleet operating with surface lines off north‐eastern Brazil was carried out between 1998 and 2000. Generalized linear models (GLMs) were used to standardize mean abundance indices using catch and fishing effort data on dolphinfish Coryphaena hippurus and to identify abundance trends in time and space, using 1215 surface line deployments. A standard relative abundance index (catch per unit effort, CPUE) was estimated for the most frequent vessels used in the sets, employing factors and coefficients generated in the GLMs. According to the models, C. hippurus catches are affected by the operating characteristics and power of different fishing vessels. These differences highlight the need for standardization of catch and effort data for artisanal fisheries. The highest mean abundance values for C. hippurus were off the state of Rio Grande do Norte, with an increasing tendency in areas with greater depths and more distant from the coast, reaching maximal values in areas whose depths range from 200 to 500 m. The highest mean abundance values occurred between April and June. The higher estimated abundance of C. hippurus in this period off the state of Rio Grande do Norte and within the 200–500 m depth range may be related to a migration pattern of food sources, as its main prey, the flying fish Hirundichthys affinis, uses floating algae as refuge and to deposit its pelagic eggs. 相似文献
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Odilo Engel Sabine Kolodziej Ulrich Dirnagl Vincent Prinz 《Journal of visualized experiments : JoVE》2011,(47)
Stroke is among the most frequent causes of death and adult disability, especially in highly developed countries. However, treatment options to date are very limited. To meet the need for novel therapeutic approaches, experimental stroke research frequently employs rodent models of focal cerebral ischaemia. Most researchers use permanent or transient occlusion of the middle cerebral artery (MCA) in mice or rats.Proximal occlusion of the middle cerebral artery (MCA) via the intraluminal suture technique (so called filament or suture model) is probably the most frequently used model in experimental stroke research. The intraluminal MCAO model offers the advantage of inducing reproducible transient or permanent ischaemia of the MCA territory in a relatively non-invasive manner. Intraluminal approaches interrupt the blood flow of the entire territory of this artery. Filament occlusion thus arrests flow proximal to the lenticulo-striate arteries, which supply the basal ganglia. Filament occlusion of the MCA results in reproducible lesions in the cortex and striatum and can be either permanent or transient. In contrast, models inducing distal (to the branching of the lenticulo-striate arteries) MCA occlusion typically spare the striatum and primarily involve the neocortex. In addition these models do require craniectomy. In the model demonstrated in this article, a silicon coated filament is introduced into the common carotid artery and advanced along the internal carotid artery into the Circle of Willis, where it blocks the origin of the middle cerebral artery. In patients, occlusions of the middle cerebral artery are among the most common causes of ischaemic stroke. Since varying ischemic intervals can be chosen freely in this model depending on the time point of reperfusion, ischaemic lesions with varying degrees of severity can be produced. Reperfusion by removal of the occluding filament at least partially models the restoration of blood flow after spontaneous or therapeutic (tPA) lysis of a thromboembolic clot in humans.In this video we will present the basic technique as well as the major pitfalls and confounders which may limit the predictive value of this model. 相似文献
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R.P. Bateman E. Hidalgo J. García C. Arroyo G.M. ten Hoopen V. Adonijah & U. Krauss 《The Annals of applied biology》2005,147(2):129-138
This article describes two field trials carried out at La Lola, Costa Rica, to assess control measures against frosty pod rot of cocoa (Theobroma cacao) caused by Moniliophthora (Crinipellis) roreri. In the first, factorial, trial the control agents were applied using motorised mistblowers (MMs) and hydraulic sprayers fitted with a narrow angle cone nozzle. There was an interaction between agents and application methods; together with previous application data for the most active fungicide (copper hydroxide), these trials indicate that best yields are achieved with sprays that maximise deposits on pods. We describe the droplet size spectra produced by a Stihl SR400 MM under a range of conditions because this has become the standard method of fungicide application in this series of trials at La Lola. The factor that had the largest effect on droplet size spectrum was the presence or the absence of a detachable baffle plate in front of the air‐shear nozzle. In both trials described here, MMs were fitted with baffle plates, a formulation pump and restrictor transmitting 550 mL min?1 to deliver an estimated equivalent of 190 L ha?1. Copper hydroxide as prophylactic applications at 1500 g a.i. ha?1 have, to date, shown the most consistent (but incomplete) improvement in healthy pod yield. Use of copper fungicides may be cost effective when farm‐gate cocoa prices exceed approximately $1.25 kg?1. In these trials, isolates of the hyperparasitic fungi Clonostachys byssicola and Trichoderma asperellum and two off‐patent triazole fungicides (bitertanol and triadimenol) made no significant improvement to healthy yields. The systemic oxathiin fungicide flutolanil, at a dosage of 300 g a.i. ha?1, appears to protect pods substantially at early stages but gives proportionately less control of M. roreri than copper at later stages of pod development. 相似文献
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Leo Breedveld 《Journal of Industrial Ecology》2000,4(2):35-48
In light of the European Directive on Integrated Pollution Prevention and Control (IPPC Directive), traditional environmental regulation can be improved using the framework of industrial ecology. The objective of the IPPC Directive is to achieve a high level of protection of the environment as a whole (Article 1) by applying the best available techniques (BAT). In essence, the IPPC Directive obliges member states of the European Union to include considerations such as resources, energy, waste, and multimedia emissions when permitting industrial installations. This is a marked contrast to traditional environmental regulation that focuses on individual media of an individual site. In order to take all considerations into account, an integrated assessment of technologies is needed, for which a standard method is currently lacking.
In this article, a systematic approach is introduced for the integrated assessment of IPPC technologies using life-cycle assessment (LCA), a form of environmental assessment that can be broadened to an overall assessment of environmental, economic, and social aspects. This systematic approach has proven to be successful for the environmental assessment of the described cases. It is suggested here that weighting can be omitted for the evaluation of IPPC technologies. Leaving the weighting step to competent authorities of member states and allowing them to consider local issues provides maximum opportunity for the subsidiarity and flexibility principles of the IPPC Directive. 相似文献
In this article, a systematic approach is introduced for the integrated assessment of IPPC technologies using life-cycle assessment (LCA), a form of environmental assessment that can be broadened to an overall assessment of environmental, economic, and social aspects. This systematic approach has proven to be successful for the environmental assessment of the described cases. It is suggested here that weighting can be omitted for the evaluation of IPPC technologies. Leaving the weighting step to competent authorities of member states and allowing them to consider local issues provides maximum opportunity for the subsidiarity and flexibility principles of the IPPC Directive. 相似文献
109.
Diversity, vitality and activities of intestinal lactic acid bacteria and bifidobacteria assessed by molecular approaches 总被引:9,自引:0,他引:9
While lactic acid bacteria and bifidobacteria have been scientifically important for over a century, many of these are marketed today as probiotics and have become a valuable and rapidly expanding sector of the food market that is leading functional foods in many countries. The human gastro-intestinal tract with its various compartments and complex microbiota is the primary target of most of these functional foods containing lactic acid bacteria and bifidobacteria (LAB&B). In addition, their use as vectors for delivery of molecules with therapeutic value to the host via the intestinal tract is being studied. This review focuses on molecular approaches for the investigation of the diversity of lactic acid bacteria and bifidobacteria in the human intestine, as well as tracking of probiotic bacteria within this complex ecosystem. Moreover, methodologies to determine the viability of the lactic acid bacteria and bifidobacteria and molecular approaches to study the mechanisms by which they adapt, establish and interact with the human host via the digestive tract, are described. 相似文献
110.
Immunohistochemical localization of IAA and ABP1 in strawberry shoot apexes during floral induction 总被引:6,自引:0,他引:6
By using an anti-indole-acetic acid (anti-IAA) monoclonal antibody and an anti-auxin-binding protein 1 (anti-ABP1) polyclonal
antibody, IAA and ABP1 were immunohistochemically localized in strawberry (Fragaria ananassa Duch.) shoot apexes during floral induction. The spatial distribution patterns of endogenous IAA and ABP1 and their dynamic
changes during floral induction were investigated. In addition, the affect of 1-N-naphthylphtalamic acid (NPA) on IAA distribution during floral induction was also analyzed. The results showed that IAA was
present in the shoot apexes throughout the floral induction process, gradually concentrating in the shoot apical meristem
(SAM). The distribution of ABP1 and its dynamic changes were similar to those of IAA. In addition, the ABP1 immune signal
in SAM gradually increased as floral induction developed. On a morphological level, these results indicate both the spatial
distribution and dynamic changes in endogenous IAA and ABP1 during the floral induction process. The close correlation found
between IAA and ABP1 indicates that a cooperation occurs during the regulation of floral induction. The results also suggest
that IAA was the significant agent for floral induction, and that SAM might be the place of the main action. Treatment with
NPA during floral induction prevented the accumulation of IAA in the SAM, delayed the process of floral differentiation and
induced an abnormal flower development. It is likely that IAA in the shoot apex is produced in young leaves and transported
through the vascular tissues to the SAM and other places of function. Finally, an appropriate amount of IAA in the SAM and
normal polar auxin transport are essential for floral induction and differentiation in strawberries. 相似文献