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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Habitat Use And Feeding Ecology Of Delphinids Inferred From Stable Isotopes And Fatty Acid Signatures

Browning, Nicole 01 January 2013 (has links)
Prey availability, directly or indirectly, affects all aspects of a predator’s life history and is a primary factor influencing habitat selection and movements. This is especially true for delphinid species where it has been documented that the behaviors and movements of dolphins are strongly influenced by food availability. Unfortunately, the feeding ecology and habitat use patterns of many of these species are poorly understood. Many methodologies that have been employed to explore these facets of dolphin ecology have limitations and constraints or are logistically infeasible. Stable isotope and fatty acid signature analyses have been used extensively on a wide variety of species and have been shown to be methodologies that overcome some of these limitations. These approaches can provide information on feeding habits and the geographic origin of the prey thereby giving tremendous insight into habitat usage patterns. The present study applied stable isotope and fatty acid signature methodologies to gain insight into the feeding ecology and habitat usage of various dolphin species to improve upon our understanding of these important facets of their life histories. The application of stable isotope analysis in ecological studies relies on both species and tissue specific measurements of parameters such as diet-tissue discrimination factors, the difference in stable isotope ratio between a consumer and its prey, and turnover rates, the change in tissue isotopic composition attributable to growth and tissue replacement. Initially, controlled studies were conducted and animals were switched from one isotopically distinct diet to another which allowed for the calculation of these values in bottlenose dolphin skin. Diet-tissue discrimination factors for dolphin skin averaged 2.20‰ for nitrogen and 0.82‰ for carbon. Average turnover rates (expressed in half-lives) in dolphin skin were 17 days for nitrogen and iv 16.5 days for carbon. The present study represents the first reported diet-tissue discrimination factors and turnover rates for carbon and nitrogen in the skin of any cetacean. Next, skin samples were collected from net-entangled and free-ranging dolphin species off the coast of South Africa and analyzed for stable carbon (δ13C) and nitrogen (δ15N) isotope ratios. The Indo-Pacific bottlenose dolphin (Tursiops aduncus), the common dolphin (Delphinus capensis), the striped dolphin (Stenella coeruleoalba), and the humpback dolphin (Sousa chinensis) all occur off the southeastern coast of South Africa with overlapping distributions. Isotopic signatures revealed resource partitioning among these four species of dolphins with differences in diets, as well as differences in the use of habitat. Mean values for δ 15N ranged from 11.92 ± 0.11‰ (n=3) for striped dolphins to 14.95 ± 0.19‰ (n=27) for humpback dolphins, indicating that these species are feeding at different trophic levels. Striped dolphin carbon isotope signatures were consistent with evidence that they typically forage further offshore (- 17.94 ± 0.14‰) and the carbon isotope values of the humpback dolphins reflected their use of inshore habitats by comparison (-15.16 ± 0.12‰). Common and bottlenose dolphins for nitrogen (13.66 ± 0.08‰, 14.35 ± 0.07‰ respectively) and carbon (-15.48 ± 0.07‰, -15.76 ± 0.06‰ respectively) fell in between these two extremes. Analyses also revealed that males and females have differences in their diets. On average, males were enriched in δ 15N by 0.74‰ compared to females suggesting some dietary differences in prey composition. Isotopic niche width has been compared to traditional measures of niches used by ecologists and was measured for these South African dolphins. Humpback and bottlenose dolphins had the largest standard elliptical area (SEA), striped dolphins had the smallest SEA, and the SEA for common dolphins was intermediate. Larger SEA values reflect a broader trophic diversity, while smaller SEA values reflect a narrower trophic diversity or a more specialized niche. v Finally, a resident group of bottlenose dolphins (Tursiops truncatus) in the Indian River Lagoon (IRL) in east central Florida were sampled and explored for differences in isotopic signatures based on sex, age category, season, and location within the IRL. In addition to stable isotope analysis, fatty acid analysis was also used to compare and contrast the findings between the two techniques. Comparison of stable isotopic signatures revealed differences among age categories and among locations. Fatty acid analysis was able to discern further and found differences in the signatures between male and female dolphins. The combination of both techniques allowed for an extensive examination into the feeding ecology and habitat utilization of these resident dolphins. The Bayesian mixing model (Stable Isotope Analysis in R- SIAR) was validated using controlled study data and was found to be accurate when inputting isotopically distinct prey items (sources). The mixing model was then used to estimate the proportions of prey items that make up the diet of Indian River Lagoon bottlenose dolphins. Two models were run in which dolphins were grouped together (model 1) and dolphins were separated by year (model 2). Results of the model reaffirm stomach content analysis results previously obtained. Stable isotope techniques were applied to various dolphin species to gain better understanding of their feeding ecology and habitat utilization. Resource partitioning was suggested for four South African dolphin species which gives crucial insight into the ecology of both at-risk and data-deficient species. These discernments will provide much needed data to conservationists and managers and contributes to our general understanding of these species. This is the first study of its kind to undertake controlled diet studies with bottlenose dolphins which determined diet-tissue discrimination values and turnover rates for carbon and nitrogen isotopes in the skin of any cetacean. The current study is also the first of its kind to attempt to vi model bottlenose dolphin diet in the Indian River using stable isotopes. Food, being a primary driver for many species, can lend explanation of things like movement patterns, habitat usage, competition, reproductive success, survival, and the spread of diseases, which has been an issue in Indian River dolphins in recent years. Dietary information modeled in this study provided new data for the relative contribution of a suite of potential prey to an apex predator in the Indian River. Data produced through the current study contributes towards a large, unprecedented step forward in understanding dolphin ecology and the roll of cetacean stable isotope ecology.
12

Är först alltid bäst? : En studie om alfabetisk bias

Celepli, Dilan, Zaito, Jessica January 2018 (has links)
Today it is common for shares to be listed in alphabetical order in newspapers, indexes, databases, watch lists and statements. Investors often face a search problem because of the thousands of available shares. It causes investors to make use of a ready-made stock list to make a financial decision. In this study, we have investigated whether there is alphabetical bias on the Swedish stock exchange and whether it has any impact on the investment decision. Previous research shows evidence that alphabetical bias occurs in the selection of shares based on alphabetically arranged lists on the US stock exchange. In this study, a quantitative method was used for data collection, later data were processed using univariate analysis, bivariate analysis, and multivariate analysis. Using the data collected, the different variables could be calculated, Tobin's Q, Market value, Name flow, Stock turnover rate, Stock price, and Age. The result cannot ensure whether alphabetical bias occurs in the Swedish stock market, however, we can with 99% certainty determine that early placed shares receive higher Tobin's Q than late placed. / Idag är det vanligt att aktier noteras i alfabetisk ordning i tidningar, index, databaser, bevakningslistor och uttalanden. Investerare möter ofta ett sök problem på grund av de tusentals tillgängliga aktierna. Det får investerarna att ta hjälp av en färdig ordnad aktielista för att fatta ett finansiellt beslut. I den här studien har vi undersökt ifall det råder alfabetisk bias på Nasdaq Stockholmsbörsen och om det har någon inverkan på investeringsbeslutet. Tidigare forskning visar belägg för att alfabetisk bias förekommer vid val av aktier utifrån alfabetisk ordnade listor på den amerikanska börsen. I denna studie tillämpades en kvantitativ metod för datainsamlingen, senare bearbetades data med hjälp av univariat analys, bivariat analys och multivariat analys. Med hjälp av den insamlade data kunde de olika variablerna räknas fram, Tobins Q, Marknadsvärde, Namnflyt, Aktieomsättningshastighet, Aktiekurs (pris) och Ålder. Resultatet kan inte säkerställa om alfabetisk bias förekommer på den svenska aktiemarknaden, dock kan vi med 99% säkerhet fastslå att tidigt placerade aktier erhåller högre Tobins Q än sent placerade.
13

Den svenska skolans personal : En kvalitativ studie / The turnover rate in the Swedish school : A qualitative studie

Smedberg, Erik, Niemelä Ingvarsson, Felix January 2020 (has links)
The Swedish school has been faced with a bad reputation the last decades. There are growing concerns regarding that the quality of the education has gone downhill, and reports are frequently made, stating a strain work environment for the school personnel, specifically the teachers. In combination with debates and reports, concerning the relatively low teacher wages and the notion that the status for the teacher profession, is lower today than before; have ultimately created a notion that teachers leave their occupation on these factors. The teacher turnover in Sweden is higher than their Nordic neighbours, but there are signs that the reasons regarding the turnover rate, are not fully understood. This study will try to give an insight on the factors behind the relatively high turnover rate in the teacher occupation. This study is based on a deductive approach where we have gathered empirical evidence, using semi-structured interviews. The candidates for the interviews were selected through a stratified sample, to examine why the turnover rate of the teacher occupation is high through motivational and institutional theories. The results of this paper contribute to a broader knowledge on the factors regarding the teacher turnover rate. Our theories about motivation- and institutional theory, have proven relevant to map the factors behind the turnover rate. Although our factors are significant for the subject, further extensive research will be needed on the matter, to give a more complete picture of the issue. This paper is written in Swedish. / Den svenska skolan har fått ett dåligt anseende de sista decennierna. Det finns en växande oro angående att kvaliteten på undervisningen har varit fallande, och frekventa rapporter görs, som påstår att skolmiljön är ansträngd för skolans personal, specifikt lärare. I kombination med debatter och rapporter, beträffande de relativt låga lärarlönerna och uppfattningen om att statusen på läraryrket skulle vara lägre idag än förut; har skapat uppfattningen att lärare lämnar yrket av dessa faktorer. Läraromsättningen i Sverige är högre än våra nordiska grannländer, men det finns tecken på att anledningarna bakom den höga personalomsättningen, är inte fullt förstådda. Denna studie kommer försöka ge en insikt av de faktorer som ligger till grund för den relativt höga personalomsättningen bland lärare. Studien är baserad på en deduktiv ansats där vi har samlat empiriskt material, genom semi-strukturerade intervjuer. Intervjukandidaterna valdes genom ett stratifierat urval, för att undersöka varför personalomsättningen bland lärare är hög, genom motivationsteorier och institutionella teorier. Undersökningens resultat bidrar till en bredare kunskap angående faktorerna bakom den höga läraromsättningen. Våra använda teorier om motivation-och institutionsteori, har visat sig relevant för att kartlägga väsentliga faktorer bakom personalomsättningen. Trots att våra faktorer är signifikanta för ämnet, kommer det krävas ytterligare betydande forskning på området för att ge en mer komplett bild om ämnet.
14

Kinetic and Morphological Studies of Pd Oxidation in O2-CH4 mixtures

Han, Jinyi 29 April 2004 (has links)
The oxidation of Pd single crystals: Pd(111), Pd(100) and Pd(110) was studied using Temperature Programmed Desorption (TPD), X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), Low Electron Energy Diffraction (LEED) and Scanning Tunneling Microscopy (STM) as they were subjected to O2 in the pressure range between 1 and 150 Torr at temperatures 600-900 K. The oxygen species formed during oxidation, the oxygen uptake dependence on the sample history, the Pd single crystal surface morphology transformations, and the catalytic methane combustion over Pd single crystals were investigated in detail. The Pd single crystal oxidation proceeded through a three-step mechanism. Namely, (1) oxygen dissociatively adsorbed on Pd surface, forming chemisorbed oxygen and then surface oxide; (2) atomic oxygen diffused through a thin surface oxide layer into Pd metal, forming near surface and bulk oxygen; (3) bulk PdO formed when a critical oxygen concentration was reached in the near surface region. The diffusion of oxygen through thin surface oxide layer into Pd metal decreased in the order: Pd(110)>Pd(100)>Pd(111). The oxygen diffusion coefficient was estimated to be around 10-16 cm2 s-1 at 600 K, with an activation energy of 80 kJ mol-1. Once bulk PdO was formed, the diffusion of oxygen through the bulk oxide layer was the rate-determining step for the palladium oxidation. The diffusion coefficient was equal to 10-18 cm2 s-1 at 600 K and the activation energy was approximately 120 kJ mol-1. The oxygen diffusion through thin surface oxide layer and bulk PdO followed the Mott-Cabrera parabolic diffusion law. The oxygen uptake on Pd single crystals depended on the sample history. The uptake amount increased with the population of the bulk oxygen species, which was achieved by high oxygen exposure at elevated temperatures, for example in 1 Torr O2 at above 820 K. Ar+ sputtering or annealing in vacuum at 1300 K depleted the bulk oxygen. The Pd single crystal surface morphology was determined by the oxidation conditions: O2 pressure, treatment temperature and exposure time. When bulk PdO was formed, the single crystal surface was covered with semi-spherical agglomerates 2-4 nm in size, which tended to aggregate to form a“cauliflower-like" superstructure. The single crystal surface area during oxidation, determined by integrating the STM image, experienced three major expansions in consistent with a three-step oxidation mechanism. The surface area on the oxidized single crystals increased in the order: Pd(110)
15

Ett avgörande första intryck : En studie om introduktionsprogrammets betydelse för företag / A crucial first impression : A study about the importance of an onboarding program for businesses

Jansson, Kristin, Svenneheim, Emelie January 2017 (has links)
Syfte: Syftet med denna studie är att öka kunskapen gällande introduktionsprogrammets betydelse för företag, för att i förlängningen möjliggöra för företag att effektivisera sitt HR-arbete.   Metodik och teoretisk referensram: En kvalitativ fallstudie med en induktiv ansats. Det empiriska materialet har samlats in genom intervjuer och fokusgrupper på tre företag inom industribranschen. vår teoretiska referensram innefattar introduktionsprogram, personalomsättning och mentorskap.   Slutsats: Inom introduktionsprogrammet finns det vissa komponenter som är mer avgörande än andra. Vilka är: struktur, upplärning, information, sociala och informella aspekter samt uppföljning. I förlängningen kan denna kunskap användas av företag och möjliggöra att de kan effektivisera sitt HR-arbete.   Vilken betydelse introduktionsprogrammet har för ett företag påverkas av förutsättningar, behov och problem inom det specifika företaget. Vissa faktorer påverkar samt har en påverkan på introduktionsprogrammet. Faktorerna kan förbättras med ett introduktionsprogram men också påverkas negativt. I förlängningen påverkar introduktionsprogrammet företags förmåga att bland annat behålla och utveckla personal, vilket kan skapa möjligheter för konkurrensfördelar och ökad lönsamhet. / Purpose: The purpose of this field study is to examine what importance an onboarding program has for businesses. By extension, businesses can develop their HR-processes in line with the findings of this study.   Methodology and theoretical reference framework: A qualitative case study within the industrial field with an inductive approach. Three different organizations within the industrial field are examined in the study. The empirical material was collected through unstructured interviews and focus groups. The theoretical reference framework includes Onboarding program, Turnover rate and Mentorship.   Conclusion: The study highlights crucial components of an onboarding program which are: structure, on the job training, information, social and informal aspects and follow-up. This knowledge can be used to make HR-processes more efficient. The findings of this paper are that the onboarding program will have a long term impact on businesses.   The importance of an onboarding program depends on the business. Advantages such as a decreased turnover rate and a motivated workforce can be earned by develop and implement an effective onboarding program within the organization.
16

Produção secundária da macrofauna bentônica da zona entremarés no segmento norte da praia do Una, litoral sul do estado de São Paulo / Secondary production of brnthonic macrofauna in the intertidal zone in the northern segment of Una beach, on the coast of the estate of São Paulo

Petracco, Marcelo 04 April 2008 (has links)
Este estudo teve como objetivo estimar a produção secundária e a taxa de renovação (P/B) do gastrópode Hastula cinerea, do isópode Excirolana armata e dos decápodes Austinixa patogoniensis e Callichirus major na zona entremarés da praia do Una, situada na Estação Ecológica Juréia-Itatins, litoral sul do estado de São Paulo. Para essa finalidade, coletas mensais foram realizadas durante o período de dezembro/03 a novembro/05 em duas áreas, A (24°28,67’S e 47°07,36’W) e B (24°27,53’S e 47°05,86’W), no segmento norte da praia que apresenta estado morfodinâmico dissipativo. H. cinerea apresentou distribuição diferencial de acordo com o tamanho dos organismos entre as áreas, com predominância de indivíduos menores na área A, o que conduziu à maior abundância, produção (ca 0,18 g PSLC m-2 ano-1) e razão P/B nessa área. Baixas razões P/B dessa espécie (entre 0,8 e 1,3 ano-1) foram decorrentes de crescimento lento, ausência de indíviduos recém-recrutados na zona entremarés e falha no recrutamento no segundo ano de estudo. Essas baixas razões foram corroboradas pela alta expectativa de vida estimada para essa espécie (4,8 anos). As estimativas de produções de E. armata, restritas à área B, foram semelhantes entre machos e fêmeas, assim como entre os anos (ca 0,25 g PSLC m-2 ano-1). As P/B dos machos (entre 3,2 e 4,3 ano-1) foram superiores às das fêmeas (ca 3,1 ano-1), decorrentes dos menores comprimentos alcançados pelos machos. Altos valores de P/B de E. armata na praia do Una foram decorrentes de crescimento rápido que se refletiram em altas taxas de mortalidade (Z) e baixas expectativas de vida. Verificou-se uma correlação significativa e inversa entre a P/B e a expectativa de vida ao utilizar estimativas dos cirolanídeos E. armata e E. braziliensis obtidas em estudos de praias arenosas brasileiras. O caranguejo A. patagoniensis apresentou densidade média anual de 1 indivíduo.galeria-1 do talassinídeo C. major e de cerca de 6 indivíduos.m-2. Essas baixas densidades conduziram à reduzida biomassa e, conseqüentemente, a uma pequena produção, apesar das consideráveis taxas de renovação estimadas para esse braquiúro (ca 2,5 ano-1). C. major apresentou a maior produção (2,33 g PSLC m-2 ano-1) dentre as espécies estudadas. Ao considerar a ampla distribuição dessa espécie ao longo da face praial na área B (mais de 50 metros), na qual foi obtida a sua produção, a estimativa em faixa de metro linear (ca 130 g PSLC m-1 ano-1) foi a mais adequada para demonstrar a importância dessa espécie. A baixa razão P/B de C. major, 0,9 ano-1, indica reduzida capacidade de compensar sobrexploração, fato esse crítico para uma espécie freqüentemente extraída em praias brasileiras para utilização como isca. Ao analisar os métodos de produção da taxa de crescimento específica em peso (TCEP) e da freqüência de comprimento (FC), a partir de algumas estimativas de estudos de praias arenosas brasileiras e do presente estudo, verificou-se que esses tenderam a gerar estimativas similares. Os métodos empíricos analisados, entretanto, tenderam a sobreou subestimar acentuadamente as estimativas de produções, não fornecendo estimativas confiáveis. Com relação às interações tróficas, as razões isotópicas estáveis de carbono e nitrogênio dos consumidores na praia do Una evidenciaram que os hábitos alimentares das espécies/gêneros estão de acordo com os referidos na literatura, no geral, e que o ecossistema da praia do Una depende basicamente do material particulado em suspensão, apesar de indícios de que o microfitobentos também possa ter papel relevante na trama trófica dessa praia. As plantas das dunas, entretanto, aparentemente não contribuem como produtores primários nesse ecossistema. / This study has as objective to estimate the secondary production and turnover rate (P/B) of the gastropod Hastula cinerea, the isopod Excirolana armata and the decapods Austinixa patogoniensis e Callichirus major in the intertidal zone of Una beach, situated in Estação Ecológica Juréia-Itatins, on the southern coast of the state of São Paulo. For that purpose, monthly samplings were carried out during the period going from December/03 to November/05 in two areas, A (24°28,67’S and 47°07,36’W) and B (24°27,53’S and 47°05,86’W), in the northern segment of the beach, which presents dissipative morphodynamic state. H. cinerea presented differential distribution according to the individual sizes between the areas, with predominance of smaller individuals in area A, which led to the higher abundance, production (ca 0.18 g PSLC m-2 ano-1) and P/B ratio in this area. Low P/B ratios of this species (between 0.8 e 1.3 ano-1) were caused by slow growth, lack of newly recruited individuals in the intertidal zone and flaws in the recruitment in the second year of study. These low ratios were corroborated by the high life span estimated for this species (4.8 years). The production estimates for E. armata, limited to area B, were similar between males and females, as well as between the years (ca 0.25 g PSLC m-2 year-1). Male P/B (between 3.2 and 4.3 year-1) were superior to the female ones (ca 3.1 year-1), resulting from the smaller lengths reached by males. High P/B values for E. armata in Una beach resulted from its fast growth, which were shown in high mortality rates (Z) and low lifespans. A significant and inverse correlation between P/B and life span was verified as estimates obtained in studies of Brazilian sandy beaches for the cirolanidae E. armata and E. braziliensis were used. The crab A. patagoniensis presented an average annual density of 1 individual.burrow-1 for the talassinidae C. major and of approximately 6 individuals.m-2. These low densities led to the limited biomass and, consequently, to a small production, in spite of the considerable turnover rates estimated for this brachyurous (ca 2.5 year-1). C. major presented the highest production (2.33 g PSLC m- 2 year-1) among the studied species. When considering the vast distribution of this species along the beach face in area B (more than 50 meters), in which its production was obtained, the estimate in linear meter strip (ca 130 g PSLC m-1 year-1) was more appropriate to demonstrate the importance of this species. The low P/B ratio of C. major, 0.9 year-1, indicates limited capacity to compensate over exploration, which is critical for a species frequently extracted in Brazilian beaches to be used as bait. While analyzing the methods of production of specific growth rate in weight (SGRW) and of length frequency (LF), from some estimates in studies of Brazilian sandy beaches and in the present study as well, it was verified that the mentioned methods tended to generate similar estimates. The empirical methods that were analyzed, however, tended to strongly super or underestimate the production estimates, thus not providing reliable estimates. With relation to trophic relations, the stable isotopic ratios of carbon and nitrogen of consumers in Una beach made it evident that the feeding habits of the species/genders are in accordance with the ones referred to in literature, generally speaking, and that the Una beach ecosystem depends basically on the suspended particulate material, in spite of indications that microphytobenthos may also play a relevant role in the trophic web in this beach. The plants in the dunes, nevertheless, apparently do not contribute as primary producers in this ecosystem.
17

Produção secundária da macrofauna bentônica da zona entremarés no segmento norte da praia do Una, litoral sul do estado de São Paulo / Secondary production of brnthonic macrofauna in the intertidal zone in the northern segment of Una beach, on the coast of the estate of São Paulo

Marcelo Petracco 04 April 2008 (has links)
Este estudo teve como objetivo estimar a produção secundária e a taxa de renovação (P/B) do gastrópode Hastula cinerea, do isópode Excirolana armata e dos decápodes Austinixa patogoniensis e Callichirus major na zona entremarés da praia do Una, situada na Estação Ecológica Juréia-Itatins, litoral sul do estado de São Paulo. Para essa finalidade, coletas mensais foram realizadas durante o período de dezembro/03 a novembro/05 em duas áreas, A (24°28,67’S e 47°07,36’W) e B (24°27,53’S e 47°05,86’W), no segmento norte da praia que apresenta estado morfodinâmico dissipativo. H. cinerea apresentou distribuição diferencial de acordo com o tamanho dos organismos entre as áreas, com predominância de indivíduos menores na área A, o que conduziu à maior abundância, produção (ca 0,18 g PSLC m-2 ano-1) e razão P/B nessa área. Baixas razões P/B dessa espécie (entre 0,8 e 1,3 ano-1) foram decorrentes de crescimento lento, ausência de indíviduos recém-recrutados na zona entremarés e falha no recrutamento no segundo ano de estudo. Essas baixas razões foram corroboradas pela alta expectativa de vida estimada para essa espécie (4,8 anos). As estimativas de produções de E. armata, restritas à área B, foram semelhantes entre machos e fêmeas, assim como entre os anos (ca 0,25 g PSLC m-2 ano-1). As P/B dos machos (entre 3,2 e 4,3 ano-1) foram superiores às das fêmeas (ca 3,1 ano-1), decorrentes dos menores comprimentos alcançados pelos machos. Altos valores de P/B de E. armata na praia do Una foram decorrentes de crescimento rápido que se refletiram em altas taxas de mortalidade (Z) e baixas expectativas de vida. Verificou-se uma correlação significativa e inversa entre a P/B e a expectativa de vida ao utilizar estimativas dos cirolanídeos E. armata e E. braziliensis obtidas em estudos de praias arenosas brasileiras. O caranguejo A. patagoniensis apresentou densidade média anual de 1 indivíduo.galeria-1 do talassinídeo C. major e de cerca de 6 indivíduos.m-2. Essas baixas densidades conduziram à reduzida biomassa e, conseqüentemente, a uma pequena produção, apesar das consideráveis taxas de renovação estimadas para esse braquiúro (ca 2,5 ano-1). C. major apresentou a maior produção (2,33 g PSLC m-2 ano-1) dentre as espécies estudadas. Ao considerar a ampla distribuição dessa espécie ao longo da face praial na área B (mais de 50 metros), na qual foi obtida a sua produção, a estimativa em faixa de metro linear (ca 130 g PSLC m-1 ano-1) foi a mais adequada para demonstrar a importância dessa espécie. A baixa razão P/B de C. major, 0,9 ano-1, indica reduzida capacidade de compensar sobrexploração, fato esse crítico para uma espécie freqüentemente extraída em praias brasileiras para utilização como isca. Ao analisar os métodos de produção da taxa de crescimento específica em peso (TCEP) e da freqüência de comprimento (FC), a partir de algumas estimativas de estudos de praias arenosas brasileiras e do presente estudo, verificou-se que esses tenderam a gerar estimativas similares. Os métodos empíricos analisados, entretanto, tenderam a sobreou subestimar acentuadamente as estimativas de produções, não fornecendo estimativas confiáveis. Com relação às interações tróficas, as razões isotópicas estáveis de carbono e nitrogênio dos consumidores na praia do Una evidenciaram que os hábitos alimentares das espécies/gêneros estão de acordo com os referidos na literatura, no geral, e que o ecossistema da praia do Una depende basicamente do material particulado em suspensão, apesar de indícios de que o microfitobentos também possa ter papel relevante na trama trófica dessa praia. As plantas das dunas, entretanto, aparentemente não contribuem como produtores primários nesse ecossistema. / This study has as objective to estimate the secondary production and turnover rate (P/B) of the gastropod Hastula cinerea, the isopod Excirolana armata and the decapods Austinixa patogoniensis e Callichirus major in the intertidal zone of Una beach, situated in Estação Ecológica Juréia-Itatins, on the southern coast of the state of São Paulo. For that purpose, monthly samplings were carried out during the period going from December/03 to November/05 in two areas, A (24°28,67’S and 47°07,36’W) and B (24°27,53’S and 47°05,86’W), in the northern segment of the beach, which presents dissipative morphodynamic state. H. cinerea presented differential distribution according to the individual sizes between the areas, with predominance of smaller individuals in area A, which led to the higher abundance, production (ca 0.18 g PSLC m-2 ano-1) and P/B ratio in this area. Low P/B ratios of this species (between 0.8 e 1.3 ano-1) were caused by slow growth, lack of newly recruited individuals in the intertidal zone and flaws in the recruitment in the second year of study. These low ratios were corroborated by the high life span estimated for this species (4.8 years). The production estimates for E. armata, limited to area B, were similar between males and females, as well as between the years (ca 0.25 g PSLC m-2 year-1). Male P/B (between 3.2 and 4.3 year-1) were superior to the female ones (ca 3.1 year-1), resulting from the smaller lengths reached by males. High P/B values for E. armata in Una beach resulted from its fast growth, which were shown in high mortality rates (Z) and low lifespans. A significant and inverse correlation between P/B and life span was verified as estimates obtained in studies of Brazilian sandy beaches for the cirolanidae E. armata and E. braziliensis were used. The crab A. patagoniensis presented an average annual density of 1 individual.burrow-1 for the talassinidae C. major and of approximately 6 individuals.m-2. These low densities led to the limited biomass and, consequently, to a small production, in spite of the considerable turnover rates estimated for this brachyurous (ca 2.5 year-1). C. major presented the highest production (2.33 g PSLC m- 2 year-1) among the studied species. When considering the vast distribution of this species along the beach face in area B (more than 50 meters), in which its production was obtained, the estimate in linear meter strip (ca 130 g PSLC m-1 year-1) was more appropriate to demonstrate the importance of this species. The low P/B ratio of C. major, 0.9 year-1, indicates limited capacity to compensate over exploration, which is critical for a species frequently extracted in Brazilian beaches to be used as bait. While analyzing the methods of production of specific growth rate in weight (SGRW) and of length frequency (LF), from some estimates in studies of Brazilian sandy beaches and in the present study as well, it was verified that the mentioned methods tended to generate similar estimates. The empirical methods that were analyzed, however, tended to strongly super or underestimate the production estimates, thus not providing reliable estimates. With relation to trophic relations, the stable isotopic ratios of carbon and nitrogen of consumers in Una beach made it evident that the feeding habits of the species/genders are in accordance with the ones referred to in literature, generally speaking, and that the Una beach ecosystem depends basically on the suspended particulate material, in spite of indications that microphytobenthos may also play a relevant role in the trophic web in this beach. The plants in the dunes, nevertheless, apparently do not contribute as primary producers in this ecosystem.
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Influence of licensed staffing hours, contract nursing, and turnover on MDS-based quality measures in Texas nursing homes

Ragsdale, Vickie Lynn 31 October 2011 (has links)
PURPOSE: Substantial research demonstrates that many nursing homes are not providing adequate quality of care for residents because of inadequate processes of care and insufficient numbers and training of nursing staff. Some residents experience poor-quality outcomes, such as pressure ulcers and unintended weight loss. To address these issues, the long-term care industry has focused on improving quality of care by improving staff education about care processes and reducing nurse turnover rate. The aim of this study was to compare the association between - licensed nurse hours of care and turnover rate to five quality measures—incidence of ADL decline, physical restraints, prevalence of pressure ulcers among residents with risk factors for skin breakdown, and prevalence of unintended weight loss. DESIGN: The study population included 618 freestanding Texas nursing facilities. A cross-sectional multiple regression analysis was conducted using 2007 data to examine the relationship between nurse staffing levels and turnover and resident outcomes with control variables for facility and resident characteristics. RESULTS: The high-risk pressure ulcer variable accounted for 10% of the variation in the regression model. LVN (hprd) was positively associated with an increase in high-risk pressure ulcers. The ADL decline variable accounted for 7.5% of the variation in the regression model, and RN hprd was positively associated with ADL decline. The prevalence of weight loss variable accounted for 3% of the variation in the regression model. RN turnover rate was approaching significance. The physical restraint variable accounted for 2% of the variation in the regression model. LVN contract hprd was significant and positively associated with an increase in physical restraint use although a minimal contribution to the model given the low percentage of LVN contract hprd. The prevalence of low-risk pressure ulcers was not significant. The control variable case mix index was positively associated with ADL decline, high-risk pressure ulcers, and weight loss. CONCLUSIONS: This research will contribute to understanding the relationship of licensed nursing staff to resident outcomes. Additionally, it will contribute to nursing education, research, and policy. While controlling for acuity using case mix index, some negative findings were still noted that requires further research. / text
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Artikelklassificering som en förutsättning för operativ lagerstyrning : En fallstudie om förbättringsmöjlighet på Alutrade / Product classification as basis for operational inventory management : A case study onimprovement opportunities at Alutrade

Olsson, Anton, Jönsson, Maja January 2023 (has links)
Background: Inventory control is a complex challenge that affects various activities on howinventory is controlled and managed. The management of inventory has a major impact on acompany's profitability and needs to be handled in different ways depending on the situationthe company is operating in. In order to improve operational inventory management forcompanies that have customer-unique products, high inventory availability and the desire forincreased inventory turnover rate, different aspects need to be addressed. Different items in acompany's assortment have different properties, and in order to control items in a goodassortment, a differentiation of the control can be developed. Purpose: The purpose of this study is to find a way to improve Alutrade's operationalinventory control and theoretically contribute with an analysis of which classification basescompanies in a similar situation should analyse when a model for differentiated control isdeveloped. The study aims to differentiate different operational models to adapt to differentitem characteristics to achieve an increased inventory turnover rate. Method: This study is treated with a deductive approach and contains both a qualitative andquantitative research method. The empirical data collected during the study consists ofinterviews, observations, focus groups and excel documents from the company's businesssystem Jeeves for calculations. The data is collected through unstructured and semi-structuredinterviews and observations. Results: By analysing Alutrade's situation, various problems could be identified in theircurrent work regarding operational inventory control. To remedy these problems, differentclassification bases for a differentiated control were analysed. This is to develop a model thatcan provide the opportunity to increase the stock turnover rate based on Alutrade'sconditions. A classification of articles is presented and gives the opportunity to applydifferent operational layer certification methods to the 9 different categories. The differentiated control handles, among other things, methods for service level, crew pointsystem, EOQ and gives recommendations for how they should be applied for each category.Through this, Alutrade can work to increase its inventory turnover rate and prioritize itsefforts where they make the most sense. Through the application of relevant classificationbases, a framework for differentiated control can be developed and different operationalinventory control methods can then be adapted for each category and provide an increase inthe inventory turnover rate. Keyword: Inventory, operational inventory control, differentiated inventory control,inventory turnover rate, classification bases, order time, order quantity, safety stock, servicelevel, ABC-XYZ analysis / Bakgrund och problemdiskussion: Lagerstyrning är en komplex utmaning som berör olikaaktiviteter om hur lager styrs och hanteras. Styrningen av lager har en stor påverkan påföretags lönsamhet och behöver hanteras på olika sätt beroende på i vilken situation företagetbefinner sig i. För att förbättra operativ lagerstyrning för företag som har kundunika artiklar,hög lagertillgänglighet och en önskan om ökad lageromsättningshastighet behöver olikaaspekter beröras. Olika artiklar i företags sortiment har olika egenskaper och för att styraartiklar på ett framgångsrikt sätt kan en differentiering av styrningen utvecklas. Syfte: Syftet med denna studie är hitta ett sätt att förbättra Alutrades operativa lagerstyrningoch teoretiskt bidra med en analys om vilka klassificeringsgrunder, företag i liknandesituation bör analysera när en modell för differentierad styrning tas fram. Studien syftar tillatt differentiera olika operativa modeller för att anpassa till olika artikelegenskaper för attuppnå en ökad lageromsättningshastighet. Metod: Denna studie behandlas med ett deduktivt angreppssätt och innehåller både enkvalitativ och kvantitativ forskningsmetod. Den empiriska datan som inhämtats under studienutgörs av intervjuer, observationer, fokusgrupper och excelunderlag från företagetsaffärssystem Jeeves för beräkningar. Datan är inhämtad genom ostrukturerade ochsemistrukturerade intervjuer och observationer. Resultat: Genom att analysera Alutrades situation kunde olika problem identifieras i derasnuvarande arbete gällande operativ lagerstyrning. För att åtgärda dessa problem analyseradesolika klassificeringsgrunder för en differentierad styrning. Detta för att ta fram en modell somkan ge möjlighet att öka lageromsättningshastigheten utifrån Alutrades förutsättningar. Enklassificering av artiklar presenteras och ger möjlighet att tillämpa olika operativalagerstyrningsmetoder till de nio olika kategorierna. Den differentierade styrningen hanterarbland annat metoder för servicenivå, besättningspunksystem, EOQ och gerrekommendationer för hur de bör tillämpas för respektive kategori. Genom detta kan4Alutrade arbeta för att öka sin lageromsättningshastighet och prioritera sina insatser dit de görmest nytta. Genom en tillämpning av relevanta klassificeringsgrunder kan ett ramverk fördifferentierad styrning utvecklas och olika operativa lagerstyrningsmetoder kan därefteranpassas för respektive kategori och ge en ökning av lageromsättningshastigheten. Nyckelord: Lager, operativ lagerstyrning, differentierad lagerstyrning,lageromsättningshastighet, klassificeringsgrunder, ordertidpunkt, orderkvantitet,säkerhetslager, servicenivå, ABC-XYZ analys
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Factors Affecting Employment Duration in the Food Retail Industry / Faktorer som Påverkar Anställningens Varaktighet i Dagligvaruhandeln

Sundling, Beata, Höft, Lova January 2023 (has links)
Measuring and tracking the employee turnover rate is a crucial part when evaluating a company’s performance. An important part of this is measuring the employment duration within an organization. The purpose of this report is to investigate if employment duration in a food retail company can be explained by predetermined variables using multiple linear regression. Data from five years ago until today has been collected and processed to analyze and fit the best choice of the linear model. Gender, employment rate, industry experience and age are the predictors used for conducting the analysis. The result shows that a low linear correlation can be seen between employment duration and the explanatory variables: gender, employment rate, industry experience and age. In the discussion, the results are analyzed as well as potential problems and improvements of the regression.

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