1,835 research outputs found

    Temporal Factors and Maturation Status as Determinants of Appetite in Atlantic Salmon

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    This thesis examines the patterns of variation in appetite in Atlantic salmon, Salmo salar, their causes and consequences. The emphasis of this study is on both their biological bases and their significance for the aquaculture industry. Chapter II: Experiments are described here that relate to daily feeding patterns and competitive interactions under both ambient and constant light and temperature regimes. Results were as follows: For yearling salmon parr under ambient light and temperature conditions: a) Consistent daily feeding rhythms with an afternoon peak were recorded in spring, while in autumn fish fed synchronously but without a consistent pattern between days. b) There was also a diurnal rhythm in frequency of aggressive interactions that was similar in both seasons. c) In spring aggression and feeding rates were negatively correlated. For salmon smolts under constant light and temperature conditions (12L:12D photoperiod): d) A clear diurnal rhythm was observed in feeding activity, with appetite peaks in early morning and late afternoon. e) When the data described in d) were separated according to fish size categories, significant patterns of diurnal variation in appetite were found for the small and medium fish but not for the larger fish. Medium-sized fish fed in a daily pattern similar to that observed at the population level, while small fish showed the highest level of feeding activity at first light and at the end of the light phase, with a marked reduction in feeding in the afternoon. Large fish maintained a relatively consistent level of feeding activity throughout the day. Chapter III: An experiment is described that was aimed at investigating the relationships between food intake, digestive efficiency and feeding regime, and to examine individual variation with respect to food intake and digestive efficiency. Results were as follows: a) Food intake and digestive efficiency varied widely between individuals under both continuous and meal-feeding regimes. b) However, while digestive efficiency was higher for continuous feeding, there was no difference between feeding regimes for food intake. c) Continuous feeding produced a negative relationship between food intake rate and digestive efficiency but no such relationship was found for meal-feeding. d) Under the meal-feeding regime there was a positive relationship between relative protein intake rate and body weight, with a weaker relationship between these two parameters under continuous feeding, suggesting a more pronounced feeding hierarchy under meal-feeding conditions. Chapter IV: This chapter describes an experiment to test whether the amount of food obtained by individual one sea-winter Atlantic salmon was related to social status. a) Food was distributed unevenly among fish; no significant relationship was found between food intake and either weight or gender. b) More successfiil fish fed earlier in a feeding session than their companions, and smaller fish tended to avoid competitors when approaching pellets. c) There was a positive relationship between frequency of being beaten to pellets and food intake, but no relationship between proportion of feeding attempts in which a fish was beaten and food intake. This suggests that fish scrambling for food were of a similar status. d) Previous studies have shown a negative relationship between the coefficient of variation in daily food intake and total food intake, but did not control for fish size. Here I found the same relationship after controlling for fish size, showing that more successful fish had less variation in their day to day consumption (corrected for body weight) than did less successfiil conspecifics. e) These data suggest that, in order to prevent food monopolisation by few individuals, the food in production cages should be presented so that it is unpredictable in time and space. Chapter V: In this chapter patterns of feeding behaviour, growth and accumulation of lipid reserves were examined in maturing fish and immature fish of the same age from the onset of the maturation cycle (autumn) to the onset of anorexia (summer). a) Maturing fish were larger and in better body condition than non-maturing fish from October until the end of the trial in July. b) Maturing fish were over-represented in samples of feeding fish from April to May (end of trial) suggesting they had a greater motivation to feed than non-maturing fish over this period. c) The period of greatest differentials in growth rate, body lipids and condition factor between the two groups of fish coincided with the period of differential feeding responses. Chapter VI: An investigation of the most useful morphometric predictors of sexual maturation in one sea-winter fish is described here, with results as follows: a) A combination of forklength and condition factor proved to be the strongest and most consistent predictor of maturation (over 88% accurate) from May until August (by which time maturing fish were losing condition and in any case could be easily distinguished by shape and colour). b) Anal height and dorsal height also gave strong predictions of reproductive status, but these parameters were of secondary importance to forklength and condition factor. c) A second trial was performed on a separate stock of fish for which forklength and condition factor were able to predict maturation to a similar level of accuracy. However, the discriminant function derived from one stock of fish did not produce the same discriminatory power when applied to the other stock

    Butorphanol for Post-Operative Analgesia - A Comparative Clinical Study with Ketorolac

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    Introduction: Butorphanol, an opioid derivative has been shown to have, in addition to its analgesic properties, several other advantageous effects like antistressor, sedative and anti-shivering action. The efficacy and safety profile of ketorolac, yet another widely used post-operative analgesic is well documented. This study aims to compare the two analgesics. Aims and objectives: This study was conducted to compare the analgesic efficacy and other effects of butorphanol and ketorolac, administered intramuscularly, in post-operative patients who have undergone lower abdominal and pelvic surgeries. Materials and methods: 50 patients undergoing lower abdominal and pelvic surgeries under general or spinal anaesthesia were randomly divided into two Groups (25 each). At a particular level of post-operative pain, the patients Groups I and II were administered intramuscular ketorolac 30mg and butorphanol 2mg respectively. The analgesic effect was studied using Visual Analogue Scale (VAS) and the verbal category scale. Patients were monitored for the sedative action, respiratory status and other vital parameters for 300 minutes and for other adverse reactions over the next twelve hours. Observations: Butorphanol provided better analgesia within the first two hours of administration, while ketorolac was more effective at 4-5 hours. Better sedative action without any significant respiratory depressant effect was demonstrated with butorphanol. There were no clinically significant hemodynamic fluctuations or adverse reactions with butorphanol or ketorolac. Conclusions: Butorphanol provides better early analgesia as compared to ketorolac with a desirable and safe sedative effect in post-operative patients who have undergone lower abdominal and pelvic surgeries

    Screening for coping style increases the power of gene expression studies

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    Background: Individuals of many vertebrate species show different stress coping styles and these have a striking influence on how gene expression shifts in response to a variety of challenges. Principal Findings: This is clearly illustrated by a study in which common carp displaying behavioural predictors of different coping styles (characterised by a proactive, adrenaline-based or a reactive, cortisol-based response) were subjected to inflammatory challenge and specific gene transcripts measured in individual brains. Proactive and reactive fish differed in baseline gene expression and also showed diametrically opposite responses to the challenge for 80% of the genes investigated. Significance: Incorporating coping style as an explanatory variable can account for some the unexplained variation that is common in gene expression studies, can uncover important effects that would otherwise have passed unnoticed and greatly enhances the interpretive value of gene expression data

    FungalTraits:A user-friendly traits database of fungi and fungus-like stramenopiles

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    The cryptic lifestyle of most fungi necessitates molecular identification of the guild in environmental studies. Over the past decades, rapid development and affordability of molecular tools have tremendously improved insights of the fungal diversity in all ecosystems and habitats. Yet, in spite of the progress of molecular methods, knowledge about functional properties of the fungal taxa is vague and interpretation of environmental studies in an ecologically meaningful manner remains challenging. In order to facilitate functional assignments and ecological interpretation of environmental studies we introduce a user friendly traits and character database FungalTraits operating at genus and species hypothesis levels. Combining the information from previous efforts such as FUNGuild and Fun(Fun) together with involvement of expert knowledge, we reannotated 10,210 and 151 fungal and Stramenopila genera, respectively. This resulted in a stand-alone spreadsheet dataset covering 17 lifestyle related traits of fungal and Stramenopila genera, designed for rapid functional assignments of environmental studies. In order to assign the trait states to fungal species hypotheses, the scientific community of experts manually categorised and assigned available trait information to 697,413 fungal ITS sequences. On the basis of those sequences we were able to summarise trait and host information into 92,623 fungal species hypotheses at 1% dissimilarity threshold

    Global patterns in endemicity and vulnerability of soil fungi

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    Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

    Global patterns in endemicity and vulnerability of soil fungi

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    Fungi are highly diverse organisms, which provide multiple ecosystem services. However, compared with charismatic animals and plants, the distribution patterns and conservation needs of fungi have been little explored. Here, we examined endemicity patterns, global change vulnerability and conservation priority areas for functional groups of soil fungi based on six global surveys using a high-resolution, long-read metabarcoding approach. We found that the endemicity of all fungi and most functional groups peaks in tropical habitats, including Amazonia, Yucatan, West-Central Africa, Sri Lanka, and New Caledonia, with a negligible island effect compared with plants and animals. We also found that fungi are predominantly vulnerable to drought, heat and land-cover change, particularly in dry tropical regions with high human population density. Fungal conservation areas of highest priority include herbaceous wetlands, tropical forests, and woodlands. We stress that more attention should be focused on the conservation of fungi, especially root symbiotic arbuscular mycorrhizal and ectomycorrhizal fungi in tropical regions as well as unicellular early-diverging groups and macrofungi in general. Given the low overlap between the endemicity of fungi and macroorganisms, but high conservation needs in both groups, detailed analyses on distribution and conservation requirements are warranted for other microorganisms and soil organisms

    Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

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    Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

    Impacts of the Tropical Pacific/Indian Oceans on the Seasonal Cycle of the West African Monsoon

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    The current consensus is that drought has developed in the Sahel during the second half of the twentieth century as a result of remote effects of oceanic anomalies amplified by local land–atmosphere interactions. This paper focuses on the impacts of oceanic anomalies upon West African climate and specifically aims to identify those from SST anomalies in the Pacific/Indian Oceans during spring and summer seasons, when they were significant. Idealized sensitivity experiments are performed with four atmospheric general circulation models (AGCMs). The prescribed SST patterns used in the AGCMs are based on the leading mode of covariability between SST anomalies over the Pacific/Indian Oceans and summer rainfall over West Africa. The results show that such oceanic anomalies in the Pacific/Indian Ocean lead to a northward shift of an anomalous dry belt from the Gulf of Guinea to the Sahel as the season advances. In the Sahel, the magnitude of rainfall anomalies is comparable to that obtained by other authors using SST anomalies confined to the proximity of the Atlantic Ocean. The mechanism connecting the Pacific/Indian SST anomalies with West African rainfall has a strong seasonal cycle. In spring (May and June), anomalous subsidence develops over both the Maritime Continent and the equatorial Atlantic in response to the enhanced equatorial heating. Precipitation increases over continental West Africa in association with stronger zonal convergence of moisture. In addition, precipitation decreases over the Gulf of Guinea. During the monsoon peak (July and August), the SST anomalies move westward over the equatorial Pacific and the two regions where subsidence occurred earlier in the seasons merge over West Africa. The monsoon weakens and rainfall decreases over the Sahel, especially in August.Peer reviewe

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

    Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

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    One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI
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