932 resultados para Most Productive Scale Size


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Bien que la plasticité ipsilesionnelle suite à un accident vasculo-cérébral (AVC) soit bien établie, la réorganisation du cortex contralésionnel et son effet sur la récupération fonctionnelle restent toujours non élucidés. Les études publiées présentent des points de vue contradictoires sur le rôle du cortex contralésionnel dans la récupération fonctionnelle. La taille de lésion pourrait être le facteur déterminant la réorganisation de ce dernier. Le but principal de cette étude fut donc d’évaluer l’effet des AVC de tailles différentes dans la région caudal forelimb area (CFA) du rat sur la réorganisation physiologique et la récupération comportementale de la main. Suite à une période de récupération spontanée pendant laquelle la performance motrice des deux membres antérieurs fut observée, les cartes motrices bilatérales du CFA et du rostral forelimb area (RFA) furent obtenues. Nous avons trouvé que le volume de lésion était en corrélation avec le niveau de récupération comportementale et l’étendue de la réorganisation des RFA bilatéraux. Aussi, les rats ayant de grandes lésions avaient des plus grandes représentations de la main dans le RFA de l’hémisphère ipsilésionnel et un déficit de fonctionnement plus persistant de la main parétique. Dans l’hémisphère contralésionnel nous avons trouvé que les rats avec des plus grandes représentations de la main dans le RFA avaient des lésions plus grandes et une récupération incomplète de la main parétique. Nos résultats confirment l’effet du volume de lésion sur la réorganisation du cortex contralésionnel et soulignent que le RFA est l’aire motrice la plus influencée dans le cortex contralésionnel.

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L’explosion de la nanotechnologie a permis l’intégration d’une multitude de nanoparticules dans des produits de consommation. Les nanoparticules d’argent (nAg) sont les plus utilisées à ces fins, selon les derniers recensements disponibles. La plupart des études toxicologiques, à ce jour, ont fait état de l’implication très évidente de l’ion Ag+ dans la toxicité aigüe des nAg; cependant, quelques études ont mis en évidence des effets toxicologiques dus aux nAg. Il y a un certain consensus à propos d’un risque de contamination des eaux douces via leur rejet par les effluents des réseaux d’aqueducs. Puisque les concentrations en Ag+ sont généralement très faibles dans les eaux douces (de l’ordre du pg L-1), de par la formation de complexes non-labiles avec des thiols (organiques et inorganiques) et des sulfures, la toxicité inhérente aux nAg pourrait ne pas être négligeable- comparativement aux tests en laboratoires. Cette étude s’intéressait donc aux mécanismes de bioaccumulation d’argent par l’algue verte C. reinhardtii suite à l’exposition à des nAg de 5 nm (enrobage d’acide polyacrylique). La bioaccumulation d’argent pour l’exposition à Ag+ servait de point de comparaison; également, les abondances de l’ARNm de l’isocitrate lyase 1 (ICL1) et de l’ARNm de Copper Transporter 2 (CTR2) étaient mesurées comme témoins biologiques de la bioaccumulation de Ag+. Les expériences ont été menées en présence d’un tampon organique (NaHEPES, 2 x 10-2 M; Ca2+, 5x 10-5 M) à pH de 7,00. Pour des expositions à temps fixe de 2 heures, la bioaccumulation d’argent pour nAg était supérieure à ce qui était prédit par sa concentration initiale en Ag+; cependant, il n’y avait pas de différence d’abondance des ARNm de ICL1 et de CTR2 entre nAg et Ag+. D’un autre côté, pour une exposition à temps variables, la bioaccumulation d’argent pour nAg était supérieure à ce qui était prédit par sa concentration initiale en Ag+ et une augmentation de l’abondance de l’ARNm de ICL1 était notée pour nAg. Cependant, il n’y avait aucune différence significative au niveau de l’abondance de l’ARNm de CTR2 entre nAg et une solution équivalente en Ag+. L’ajout d’un fort ligand organique (L-Cystéine; log K= 11,5) à une solution de nAg en diminuait radicalement la bioaccumulation d’argent par rapport à nAg-sans ajout de ligand. Par contre, l’abondance des ARNm de ICL1 et de CTR2 étaient stimulées significativement par rapport à une solution contrôle non-exposée à nAg, ni à Ag+. Les résultats suggéraient fortement que les nAg généraient des ions Ag+ au contact de C. reinhardtii.

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L’essence de la théorie du capital humain (Becker, 1964) prédit que l’investissement dans les activités visant à renforcer le potentiel productif des individus se traduit par une augmentation de leurs revenus tout au long de leur carrière (Benjamin, Gunderson et Riddell, 2002 : 245). Pour le groupe occupationnel constitué par les artistes, la littérature s’accorde pourtant pour dire que l’investissement en capital humain demeure rentable financièrement, mais à un niveau sensiblement moindre que pour les autres professions (Snooks, 1983; Filer, 1990; Rengers, 2002; Alper et Wassall, 2006). Nous exposons les théories du capital humain, des différences de salaire compensatoires (Smith, 1776) ainsi que la théorie hédonique des salaires (Rosen, 1974; Rosen et Thaler, 1975) afin d’atteindre deux objectifs. Premièrement, nous cherchons à vérifier empiriquement l’impact de l’acquisition de capital humain sur le revenu d’emploi autonome des artistes canadiens . Dans une autre perspective, nous souhaitons également évaluer la nature et la taille du différentiel de revenu d’emploi par rapport aux autres professions et investiguer les facteurs sur lesquels il repose. Le projet comble un vide dans la littérature portant sur les déterminants du revenu d’emploi des artistes canadiens et permet de réfléchir à l’orientation des politiques publiques culturelles entourant la formation académique de ceux-ci. Nous employons une analyse de régression multivariée sur des variables de capital humain en ayant recours aux données du recensement canadien de 2006 . Plus précisément, nous tentons de mesurer la relation associative entre le revenu de travail autonome exprimé sous forme de logarithme du salaire hebdomaire des artistes canadiens et la scolarité, l’expérience de travail, le sexe, le statut marital légal, la profession/spécialité artistique (classification selon la CNP-S, en vigueur en 2006), le statut d’immigrant, le statut de minorité visible, le fait d’être le principal soutien de la famille ainsi que la zone de résidence. Les résultats nous apprennent que la scolarité demeure rentable financièrement pour la majorité des spécialités artistiques, mais que des profils de scolarité précis ont avantage à être privilégiés selon la spécialité artistique. L’expérience de travail s’avère quant à elle moins rentable au niveau de la rémunération que chez les autres professions, tout comme elle est moins avantageuse financière pour les artistes issus des arts performatifs chez qui la carrière se termine habituellement assez tôt. En ce qui concerne l’effet des variables sociodémographiques, soulignons seulement que le fait d’être de sexe masculin est associé à de plus hauts revenus chez les artistes, mais dans une proportion moindre que chez les autres professions. Quant aux effets des statuts d’immigrant et de minorité visible sur le revenu d’emploi, ceux-ci varient mais demeurent moins pénalisants chez les artistes, ce qui suggère que le marché du travail culturel serait moins discriminant que le marché du travail traditionnel.

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La documentation sur les interventions de gratuité sélective des soins est encore insuffisante et surtout focalisée sur leurs effets au niveau de l’utilisation des services de santé ou de la réduction des dépenses catastrophiques. Leurs effets sociaux sont occultés par les recherches. L’originalité de cette thèse tient au fait qu’elle constitue la première recherche qui s’est consacrée à cela. Ses résultats sont structurés en quatre articles. Le premier article montre que la gratuité sélective des soins est socialement acceptée, car elle est vue comme contributive au renforcement du lien social. Toutefois, le choix des cibles bénéficiaires est remis en cause. Au nom d’arguments moraux et humanitaires, les communautés préfèrent inclure les personnes âgées dans le ciblage, quitte à les substituer aux plus pauvres, les indigents. Néanmoins, le ciblage des indigents n’a pas entrainé de stigmatisation. Le deuxième article souligne que la fourniture gratuite de soins aux populations par les villageois membres des comités de gestion des centres de santé a contribué au renforcement de leur pouvoir d’agir et celui de leur organisation. Cependant, pour que la participation communautaire soit effective, l’étude montre qu’elle doit s’accompagner d’un renforcement des compétences des communautés Le troisième article soutient que la suppression du paiement des soins a permis aux femmes de ne plus avoir besoin de s’endetter ou de négocier constamment avec leurs maris pour disposer de l’argent des consultations prénatales ou des accouchements. Ce qui a contribué à leur empowerment et rendu possible l’atteinte d’autres réalisations au plan sanitaire (augmentation des accouchements assistés), mais aussi social (renforcement de leur position sociale). Le quatrième article s’est intéressé à étudier la pérennité de ces interventions de gratuité des soins. Les résultats suggèrent que le degré de pérennité de la prise en charge des indigents (district de Ouargaye) est moyen correspondant au degré le plus élevé dans une organisation alors que celui de la gratuité des accouchements et des soins pour les enfants (districts de Dori et de Sebba) est précaire. Cette différence de pérennité est due principalement à la différence d’échelle (taille des populations concernées) et d’ampleur (inégalité des ressources en jeu) entre ces interventions. D’autres facteurs ont aussi influencé cette situation comme les modalités de mise en œuvre de ces interventions (approche projet à Dori et Sebba vs approche communautaire à Ouargaye) Au plan des connaissances, l’étude a mis en exergue plusieurs points dont : 1) l’importance de prendre en compte les valeurs des populations dans l’élaboration des réformes ; 2) la pertinence sociale du ciblage communautaire de sélection des indigents ; 3) la capacité des communautés à prendre en charge leurs problèmes de santé pourvu qu’on leur donne les ressources financières et la formation minimale ; 4) l’importance du processus de pérennisation, notamment la stabilisation des ressources financières nécessaires à la continuité d’une intervention et l’adoption de risques organisationnels dans sa gestion ; 5) l’importance de la suppression de la barrière financière au point de services pour renforcer l’empowerment des femmes et son corolaire leur recours aux services de soins.

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The studies were conducted in nine stations with varying ecological characteristics along Cochin backwaters and adjoining canals. Many workers opined that the distribution of rotifers is cosmopolitan. The significance of rotifers as first food for early larvae was indicated by Fujita. Aquaculture is a fast growing field in fisheries sector and it is gaining more importance as the fish landings and supply are getting irregular. A consistent supply of fish/shellfish can only be achieved through aquaculture. The success of any culture activity depends on the timely production of seeds of finfishes/shellfishes. The availability of wild seed is seasonal and erratic. So, a dependable source of seed of fishes and shellfishes is possible only through large scale production in hatchery. A successful seed production activity depends on the availability of a variety of suitable live feed organisms in sufficient quantities at the proper time for use in the larval stages. As the live feeds promote high growth rates, easy digestion, assimilation and the quality of not contaminating the culture water when compared to other artificial feeds, make the culture of live feed organisms the principal means of providing food for the larvae of finfishes and shellfishes. Rotifers are considered to be an excellent and indispensable food for larvae of many finfishes and crustaceans. It (1960) was the first to culture Brachionus plicatilis for feeding marine fish larvae, and now it is being extensively used as live feed in hatcheries all over the world. They are a group of microscopic organisms coming under the Phylum Rotifera which comprises of about 2000 species. Their slow swimming habits, ability to tolerate a wide range of salinities, parthenogenetic mode of reproduction and ability to get enriched easily, make rotifers an ideal live feed organism. The major factors such as temperature, salinity and food that influence the reproductive potential and thereby the population size of rotifer, Salinity is one of the most important aspect influencing the reproductive rate of rotifers. The feed type and feed concentration play a vital role in influencing the reproductive rate of rotifers. For culture of rotifers, the commonly used micro algae belong to Chlorella, Nannochloropsis, Isochrysis and Tetraselmis. While some studies have suggested that, algal diet has little effect on reproductive rates in 1979 while using the rotifer, Brachionus plicatilis as feed for the larvae of red sea bream, Pagrus major. It is generally accepted that rotifers play a pivotal role in the successful rearing of marine fish larvae.

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We are in the cutting edge of a new era of development without leaving any promises to next generation. But the scale and size of the problem are only partially blamed. The juggernaut of Globalisation has trampled upon whatever little hope we might have had making a quick transition to a less energy – intensive world. “Environment friendliness begins at home”. Our quest for productivity and profitability should progress simultaneous with our cooperative responsibility of leaving behind a clean and green earth for the generation to come. Climate change is the most pressing global environmental challenge being faced by humanity, with the quest for better productivity for our fragile ecosystem. It is too late to rely solely on reduction in Green house gas emissions to mitigate climate change although this is undoubtedly crucial. Coastal belts are more prone to these devastating impacts and its protection is an intensive filed of research. The present study describes how the colourful Carotenoids and Chlorophylls can be used in rapid hand on tool in conjunction with molecular biology to open sources and it also explores the fate of organic matter in the aquatic system and underlying sediments.

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One-pot acetalizations of cyclohexanone. acetophenone and benzophenone were carried out using methanol over H-montmorillonite clay (a mesoporous material). silica, alumina, and different zeolites such as HFAU-Y.HBeta, H-ZSM-5, and H-mordenite. In all the cases a single product-the corresponding dimethylacetal-was obtained in high yields. Hemiacetal formation was not observed with any catalyst. A comparison of catalytic activity indicated that montmorillonite K-10 is the most active catalyst for the reaction. As evidenced by the reaction time studies, the catalyst decay is greater over the zeolite catalyst than over the clay.

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A socio-economic research is required as an attempt to address the socio-economic issues facing small-scale fisheries. A study of the socio economic conditions of small-scale fishermen is a prerequisite for good design and successful implementation of effective assistance Programmes. It will provide an overall pidure of the structure, activities and standards of living of small-scale fisherfolk The study is confined to the coastal districts of Ernakulam, Thrissur and Malappuram districts. It also gives a picture of socio-economic conditions of the fisher folk in the study area. The variables that may depict the standard of living of the small-scale fisherfolk are occupational structure, family size, age structure, income, expenditure, education, housing and other social amenities. It attempts to see the asset creation of the fisherfolk with the help of government agencies, and the nature of savings and expenditure pattern of the fisherfolk. It also provides a picture of the indebtedness of the fisherfolk in the study area. The study analyses the schemes implemented by the government through its agencies, like Fisheries Department, Matsyaboard, and Matsyafed; and the awareness of fisherfolk regarding these schemes, their attitude and reactions, the extent of accessibility, and the viability of the schemes.

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This thesis entitled “Contribution of size fractions of planktonic algae to primary organic productivity in the coastal waters of cochin,south west coast of india”. Marine ecosystems planktonic algae are the most important primary producers on wliich considerable attention is being given on account of their supreme status in the marine food chain.The study of primary production in the Indian Ocean started With DANA (I928-30),, John Murray t I933-34). Discovery ( I934) and Albatross (I947-48) expeditions which tried to evaluate productivity from nutrients and standing crop of phytoplankton .The bioproductivity of the marine environment is dependent on various primary producers. ranging in size from picoplankton to larger macro phytoplankton. The quantity and quality of various size fractions of planktonic algae at any locality depend mainly on the hydrographic conditions of the area .In the coastal waters of Cochin- south west coast of lndia. Planktonic algal community is composed mainly of the diatoms, the dinoflagellates, the blue-green algae and the silicoflagellates, the former two contributing the major flora and found distributed in the all size fractions. The maximum number of species of diatoms at station 1 and station 2 was found in the pre-monsoon season.. The size groups of planktonic algae greater than 53 um are dominated by filamentous- chain forming and colonial diatoms. The coastal waters of Cochin. planktonic algae less than 53 um in size contribute significantly to primary productivity and the biodiversity of the microflora, indicating the presence of rich fishery resources in the south west coast of india.The study of different size fractions of planktonic algae and their relative contribution to the primary organic production is a useful tool for the estimation of the quantity and quality of fisheries.A deeper investigation on the occurrence of these microalgae and proper identification of their species would be of immense help for the assessment of the specificity and magnitude of fishery resources.

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The preceding discussion and review of literature show that studies on gear selectivity have received great attention, while gear efficiency studies do not seem to have received equal consideration. In temperate waters, fishing industry is well organised and relatively large and well equipped vessels and gear are used for commercial fishing and the number of species are less; whereas in tropics particularly in India, small scale fishery dominates the scene and the fishery is multispecies operated upon by nmltigear. Therefore many of the problems faced in India may not exist in developed countries. Perhaps this would be the reason for the paucity of literature on the problems in estimation of relative efficiency. Much work has been carried out in estimating relative efficiency (Pycha, 1962; Pope, 1963; Gulland, 1967; Dickson, 1971 and Collins, 1979). The main subject of interest in the present thesis is an investigation into the problems in the comparison of fishing gears. especially in using classical test procedures with special reference to the prevailing fishing practices (that is. with reference to the catch data generated by the existing system). This has been taken up with a view to standardizing an approach for comparing the efficiency of fishing gear. Besides this, the implications of the terms ‘gear efficiency‘ and ‘gear selectivity‘ have been examined and based on the commonly used selectivity model (Holt, 1963), estimation of the ratio of fishing power of two gear has been considered. An attempt to determine the size of fish for which a gear is most efficient.has also been made. The work has been presented in eight chapters

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Regional climate models are becoming increasingly popular to provide high resolution climate change information for impacts assessments to inform adaptation options. Many countries and provinces requiring these assessments are as small as 200,000 km2 in size, significantly smaller than an ideal domain needed for successful applications of one-way nested regional climate models. Therefore assessments on sub-regional scales (e.g., river basins) are generally carried out using climate change simulations performed for relatively larger regions. Here we show that the seasonal mean hydrological cycle and the day-to-day precipitation variations of a sub-region within the model domain are sensitive to the domain size, even though the large scale circulation features over the region are largely insensitive. On seasonal timescales, the relatively smaller domains intensify the hydrological cycle by increasing the net transport of moisture into the study region and thereby enhancing the precipitation and local recycling of moisture. On daily timescales, the simulations run over smaller domains produce higher number of moderate precipitation days in the sub-region relative to the corresponding larger domain simulations. An assessment of daily variations of water vapor and the vertical velocity within the sub-region indicates that the smaller domains may favor more frequent moderate uplifting and subsequent precipitation in the region. The results remained largely insensitive to the horizontal resolution of the model, indicating the robustness of the domain size influence on the regional model solutions. These domain size dependent precipitation characteristics have the potential to add one more level of uncertainty to the downscaled projections.

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A nanocomposite is a multiphase solid material where one of the phases has one, two or three dimensions of less than 100 nanometers (nm), or structures having nano-scale repeat distances between the different phases that make up the material. In the broadest sense this definition can include porous media, colloids, gels and copolymers, but is more usually taken to mean the solid combination of a bulk matrix and nano-dimensional phase(s) differing in properties due to dissimilarities in structure and chemistry. The mechanical, electrical, thermal, optical, electrochemical, catalytic properties of the nanocomposite will differ markedly from that of the component materials. Size limits for these effects have been proposed, <5 nm for catalytic activity, <20 nm for making a hard magnetic material soft, <50 nm for refractive index changes, and <100 nm for achieving superparamagnetism, mechanical strengthening or restricting matrix dislocation movement. Conducting polymers have attracted much attention due to high electrical conductivity, ease of preparation, good environmental stability and wide variety of applications in light-emitting, biosensor chemical sensor, separation membrane and electronic devices. The most widely studied conducting polymers are polypyrrole, polyaniline, polythiophene etc. Conducting polymers provide tremendous scope for tuning of their electrical conductivity from semiconducting to metallic region by way of doping and are organic electro chromic materials with chemically active surface. But they are chemically very sensitive and have poor mechanical properties and thus possessing a processibility problem. Nanomaterial shows the presence of more sites for surface reactivity, they possess good mechanical properties and good dispersant too. Thus nanocomposites formed by combining conducting polymers and inorganic oxide nanoparticles possess the good properties of both the constituents and thus enhanced their utility. The properties of such type of nanocomposite are strongly depending on concentration of nanomaterials to be added. Conducting polymer composites is some suitable composition of a conducting polymer with one or more inorganic nanoparticles so that their desirable properties are combined successfully. The composites of core shell metal oxide particles-conducting polymer combine the electrical properties of the polymer shell and the magnetic, optical, electrical or catalytic characteristics of the metal oxide core, which could greatly widen their applicability in the fields of catalysis, electronics and optics. Moreover nanocomposite material composed of conducting polymers & oxides have open more field of application such as drug delivery, conductive paints, rechargeable batteries, toners in photocopying, smart windows, etc.The present work is mainly focussed on the synthesis, characterization and various application studies of conducting polymer modified TiO2 nanocomposites. The conclusions of the present work are outlined below, Mesoporous TiO2 was prepared by the cationic surfactant P123 assisted hydrothermal synthesis route and conducting polymer modified TiO2 nanocomposites were also prepared via the same technique. All the prepared systems show XRD pattern corresponding to anatase phase of TiO2, which means that there is no phase change occurring even after conducting polymer modification. Raman spectroscopy gives supporting evidence for the XRD results. It also confirms the incorporation of the polymer. The mesoporous nature and surface area of the prepared samples were analysed by N2 adsorption desorption studies and the mesoporous ordering can be confirmed by low angle XRD measurementThe morphology of the prepared samples was obtained from both SEM & TEM. The elemental analysis of the samples was performed by EDX analysisThe hybrid composite formation is confirmed by FT-IR spectroscopy and X-ray photoelectron spectroscopyAll the prepared samples have been used for the photocatalytic degradation of dyes, antibiotic, endocrine disruptors and some other organic pollutants. Photocatalytic antibacterial activity studies were also performed using the prepared systemsAll the prepared samples have been used for the photocatalytic degradation of dyes, antibiotic, endocrine disruptors and some other organic pollutants. Photocatalytic antibacterial activity studies were also performed using the prepared systems Polyaniline modified TiO2 nanocomposite systems were found to have good antibacterial activity. Thermal diffusivity studies of the polyaniline modified systems were carried out using thermal lens technique. It is observed that as the amount of polyaniline in the composite increases the thermal diffusivity also increases. The prepared systems can be used as an excellent coolant in various industrial purposes. Nonlinear optical properties (3rd order nonlinearity) of the polyaniline modified systems were studied using Z scan technique. The prepared materials can be used for optical limiting Applications. Lasing studies of polyaniline modified TiO2 systems were carried out and the studies reveal that TiO2 - Polyaniline composite is a potential dye laser gain medium.

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Among the decapod crustaceans, brachyuran crabs or the true crabs occupy a very significant position due to their ecological and economic value. Crabs support a sustenance fishery in India, even though their present status is not comparable to that of shrimps and lobsters. They are of great demand in the domestic market as well as in the foreign markets. In addition to this, brachyuran crabs are of great ecological importance. They form the conspicuous members of the mangrove ecosystems and play a significant role in detritus formation, nutrient recycling and dynamics of the ecosystem. Considering all these factors, crabs are often considered to be the keystone species of the mangrove ecosystem. Though several works have been undertaken on brachyuran crabs world –wide as well as within the country, reports on the brachyuran crabs of Kerala waters are very scanty. Most of the studies done on brachyuran fauna were from the east coast of India and a very few works from the west coast. Among the edible crabs, mud crabs belonging to genus Scylla forms the most important due to their large size and taste. They are being exported on a large scale to the foreign markets like Singapore, Malaysia and Hong Kong. Kerala is the biggest supplier of live mud crabs and Chennai is the major centre of live mud crab export. However, there exists considerable confusion regarding the identification of mud crabs because of the subtle morphological differences between the species.In this context, an extensive study was undertaken on the brachyuran fauna of Cochin Backwaters, Kerala, India, to have a basic knowledge on their diversity, habitat preference and systematics. The study provides an attempt to resolve the confusion pertaining in the species identification of mud crabs belonging to Genus Scylla. Diversity study revealed the occurrence of 23 species of brachyuran crabs belonging to 16 genera and 8 families in the study area Cochin Backwaters. Among the families, the highest number of species was recorded from Family Portunidae .Among the 23 crab species enlisted from the Cochin backwaters, 5 species are of commercial importance and contribute a major share to the crustacean fishery of the Cochin region. It was observed that, the Cochin backwaters are invaded by certain marine migrant species during the Post monsoon and Pre monsoon periods and they are found to disappear with the onset of monsoon. The study reports the occurrence of the ‘herring bow crab’ Varuna litterata in the Cochin backwaters for the first time. Ecological studies showed that the substratum characteristics influence the occurrence, distribution and abundance of crabs in the sampling stations rather than water quality parameters. The variables which affected the crab distribution the most were Salinity, moisture content in the sediment, organic carbon and the sediment texture. Besides the water and sediment quality parameters, the most important factor influencing the distribution of crabs is the presence of mangroves. The study also revealed that most of the crabs encountered from the study area preferred a muddy substratum, with high organic carbon content and high moisture content. In the present study, an identification key is presented for the brachyuran crabs occurring along the study area the Cochin backwaters and the associated mangrove patches, taking into account the morphological characters coupled with the structure of third maxillipeds, first pleopods of males and the shape of male abdomen. Morphological examination indicated the existence of a morphotype which is comparable with the morphological features of S. tranquebarica, the morphometric study and the molecular analyses confirmed the non existence of S. tranquebarica in the Cochin backwaters.

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The study covers theFishing capture technology innovation includes the catching of aquatic animal, using any kind of gear techniques, operated from a vessel. Utilization of fishing techniques varies, depending upon the type of fisheries, and can go from a basic and little hook connected to a line to huge and complex mid water trawls or seines operated by large fishing vessels.The size and autonomy of a fishing vessel is largely determined by its ability to handle, process and store fish in good condition on board, and thus these two characteristics have been greatly influenced by the introduction and utilization of ice and refrigeration machinery. Other technological developments especially hydraulic hauling machinery, fish finding electronics and synthetic twines have also had a major impact on the efficiency and profitability of fishing vessels.A wide variety of fishing gears and practices ranging from small-scale artisanal to advanced mechanised systems are used for fish capture in Kerala. Most important among these fishing gears are trawls, seines, lines, gillnets and entangling nets and traps The modern sector was introduced in 1953 at Neendakara, Shakthikulangara region under the initiative of Indo-Norwegian project (INP). The novel facilities introduced in fishing industry by Indo- Norwegian project accordingly are mechanically operated new boats with new fishing nets. Soon after mechanization, motorization programme gained momentum in Kerala especially in Alleppey, Ernakulam and Kollam districts.

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Summary: Productivity and forage quality of legume-grass swards are important factors for successful arable farming in both organic and conventional farming systems. For these objectives the botanical composition of the swards is of particular importance, especially, the content of legumes due to their ability to fix airborne nitrogen. As it can vary considerably within a field, a non-destructive detection method while doing other tasks would facilitate a more targeted sward management and could predict the nitrogen supply of the soil for the subsequent crop. This study was undertaken to explore the potential of digital image analysis (DIA) for a non destructive prediction of legume dry matter (DM) contribution of legume-grass mixtures. For this purpose an experiment was conducted in a greenhouse, comprising a sample size of 64 experimental swards such as pure swards of red clover (Trifolium pratense L.), white clover (Trifolium repens L.) and lucerne (Medicago sativa L.) as well as binary mixtures of each legume with perennial ryegrass (Lolium perenne L.). Growth stages ranged from tillering to heading and the proportion of legumes from 0 to 80 %. Based on digital sward images three steps were considered in order to estimate the legume contribution (% of DM): i) The development of a digital image analysis (DIA) procedure in order to estimate legume coverage (% of area). ii) The description of the relationship between legume coverage (% area) and legume contribution (% of DM) derived from digital analysis of legume coverage related to the green area in a digital image. iii) The estimation of the legume DM contribution with the findings of i) and ii). i) In order to evaluate the most suitable approach for the estimation of legume coverage by means of DIA different tools were tested. Morphological operators such as erode and dilate support the differentiation of objects of different shape by shrinking and dilating objects (Soille, 1999). When applied to digital images of legume-grass mixtures thin grass leaves were removed whereas rounder clover leaves were left. After this process legume leaves were identified by threshold segmentation. The segmentation of greyscale images turned out to be not applicable since the segmentation between legumes and bare soil failed. The advanced procedure comprising morphological operators and HSL colour information could determine bare soil areas in young and open swards very accurately. Also legume specific HSL thresholds allowed for precise estimations of legume coverage across a wide range from 11.8 - 72.4 %. Based on this legume specific DIA procedure estimated legume coverage showed good correlations with the measured values across the whole range of sward ages (R2 0.96, SE 4.7 %). A wide range of form parameters (i.e. size, breadth, rectangularity, and circularity of areas) was tested across all sward types, but none did improve prediction accuracy of legume coverage significantly. ii) Using measured reference data of legume coverage and contribution, in a first approach a common relationship based on all three legumes and sward ages of 35, 49 and 63 days was found with R2 0.90. This relationship was improved by a legume-specific approach of only 49- and 63-d old swards (R2 0.94, 0.96 and 0.97 for red clover, white clover, and lucerne, respectively) since differing structural attributes of the legume species influence the relationship between these two parameters. In a second approach biomass was included in the model in order to allow for different structures of swards of different ages. Hence, a model was developed, providing a close look on the relationship between legume coverage in binary legume-ryegrass communities and the legume contribution: At the same level of legume coverage, legume contribution decreased with increased total biomass. This phenomenon may be caused by more non-leguminous biomass covered by legume leaves at high levels of total biomass. Additionally, values of legume contribution and coverage were transformed to the logit-scale in order to avoid problems with heteroscedasticity and negative predictions. The resulting relationships between the measured legume contribution and the calculated legume contribution indicated a high model accuracy for all legume species (R2 0.93, 0.97, 0.98 with SE 4.81, 3.22, 3.07 % of DM for red clover, white clover, and lucerne swards, respectively). The validation of the model by using digital images collected over field grown swards with biomass ranges considering the scope of the model shows, that the model is able to predict legume contribution for most common legume-grass swards (Frame, 1992; Ledgard and Steele, 1992; Loges, 1998). iii) An advanced procedure for the determination of legume DM contribution by DIA is suggested, which comprises the inclusion of morphological operators and HSL colour information in the analysis of images and which applies an advanced function to predict legume DM contribution from legume coverage by considering total sward biomass. Low residuals between measured and calculated values of legume dry matter contribution were found for the separate legume species (R2 0.90, 0.94, 0.93 with SE 5.89, 4.31, 5.52 % of DM for red clover, white clover, and lucerne swards, respectively). The introduced DIA procedure provides a rapid and precise estimation of legume DM contribution for different legume species across a wide range of sward ages. Further research is needed in order to adapt the procedure to field scale, dealing with differing light effects and potentially higher swards. The integration of total biomass into the model for determining legume contribution does not necessarily reduce its applicability in practice as a combined estimation of total biomass and legume coverage by field spectroscopy (Biewer et al. 2009) and DIA, respectively, may allow for an accurate prediction of the legume contribution in legume-grass mixtures.