969 resultados para Sampling method
Resumo:
Plusieurs études à grande échelle ont identifié la modification ou la perte d’habitats comme menace principale à la conservation des communautés de poissons d’eau douce. Au Canada, « aucune perte nette dans la capacité productive des habitats » (NNL) est le principe directeur de la politique de gestion des habitats du ministère des Pêches et Océans. Le respect du NNL implique l’avancement des connaissances au niveau des relations entre les poissons et leurs habitats, de même que des outils pour quantifier l’impact de la modification des habitats sur les poissons. Les modèles d’utilisation de l’habitat des poissons (FHUM) sont des outils qui permettent d’améliorer nos connaissances des relations poissons – habitat, de prédire la distribution des espèces, mais aussi leurs densités, biomasses ou abondances, sur la base des caractéristiques de l’environnement. L’objectif général de mon mémoire est d’améliorer la performance des FHUM pour les rivières des basses Laurentides, en suggérant des perfectionnements au niveau de 2 aspects cruciaux de l’élaboration de tels modèles : la description précise de la communauté de poissons et l’utilisation de modèles statistiques efficaces. Dans un premier chapitre, j’évalue la performance relative de la pêcheuse électrique et de l’échantillonnage en visuel (plongée de surface) pour estimer les abondances des combinaisons d’espèces et de classes de taille des poissons en rivière. J’évalue aussi l’effet des conditions environnementales sur les différences potentielles entre les communautés observées par ces 2 méthodes d’échantillonnage. Pour ce faire, 10 sections de rivière de 20 m de longueur ont été échantillonnées à l’aide de ces 2 méthodes alors qu’elles étaient fermées par des filets de blocage. 3 plongeurs performèrent l’échantillonnage en visuel en se déplaçant de l’aval vers l’amont des sections, tout en dénombrant les espèces et classes de taille. Par la suite, nous avons fait 3 passages de pêcheuse électrique et les abondances furent estimées grâce à un modèle restreint de maximum de vraisemblance, basé sur la diminution des abondances observées. De plus grandes abondances de poissons furent observées en visuel qu’avec la pêcheuse électrique à tous les sites. La richesse spécifique observée en visuel était plus élevée (6/10) ou égale (4/10) à celle observée avec la pêcheuse électrique. Les différences entre les communautés de poissons observées à l’aide de ces 2 méthodes ne purent être reliées aux conditions environnementales. Les résultats de cette expérience sont contraires à ceux de toutes les études comparant ces 2 méthodes d’échantillonnage, lesquels suggèrent une supériorité de la pêcheuse électrique. Les conditions environnementales de notre expérience étaient distinctes de celles observées dans les autres études (absence d’arbres tombés dans l’eau, très peu de substrats grossiers), mais la différence la plus marquante était en terme de communauté de poissons observée (dominance des cyprinidés et des centrarchidés plutôt que des salmonidés). Je termine ce chapitre en suggérant que les caractéristiques comportementales favorisant l’évitement de la capture (formation de bancs) et facilitant l’observation en visuel (curiosité) sont responsables de la supériorité de la plongée de surface pour échantillonner les communautés dans les rivières des basses Laurentides. Dans un deuxième chapitre, je développe des FHUM pour des communautés de poissons de rivière ayant plusieurs espèces. Dans le but de simplifier la modélisation de telles communautés et d’améliorer notre compréhension des relations poissons – habitat, j’utilise les concepts de guilde écologique et de filtre environnemental pour explorer les relations entre les guildes formées sur la bases de différents types de traits (reproducteurs, taxonomiques, éco-morphologiques et alimentaires) et les conditions environnementales locales à l’échelle du méso-habitat. Les modèles d’habitats basés sur les guildes reproductrices ont clairement surpassé les autres modèles, parce que l’habitat de fraie reflète l’habitat de préférence en dehors de la période de reproduction. J’ai également utilisé l’approche inverse, c’est à dire définir des guildes d’utilisation de l’habitat et les mettre en relation avec les traits des espèces. Les traits reliés à l’alimentation des poissons ont semblés être les meilleurs pour expliquer l’appartenance aux groupes d’utilisation de l’habitat, mais le modèle utilisé ne représentait pas bien la relation entre les groupes. La validation de notre modèle basé sur les guildes reproductrices avec un jeu de données indépendant pourrait confirmer notre découverte, laquelle représente une manière prometteuse de modéliser les relations poissons – environnement dans des communautés de poissons complexes. En conclusion, mon mémoire suggère d’importantes améliorations aux FHUM pour les communautés de poissons des basses Laurentides, en suggérant de prendre en compte les caractéristiques biologiques des cours d’eau dans le choix d’une méthode d’échantillonnage, et également en utilisant une méthode prometteuse pour simplifier les FHUM de communautés de poissons complexes : les guildes reproductrices.
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We propose a novel, simple, efficient and distribution-free re-sampling technique for developing prediction intervals for returns and volatilities following ARCH/GARCH models. In particular, our key idea is to employ a Box–Jenkins linear representation of an ARCH/GARCH equation and then to adapt a sieve bootstrap procedure to the nonlinear GARCH framework. Our simulation studies indicate that the new re-sampling method provides sharp and well calibrated prediction intervals for both returns and volatilities while reducing computational costs by up to 100 times, compared to other available re-sampling techniques for ARCH/GARCH models. The proposed procedure is illustrated by an application to Yen/U.S. dollar daily exchange rate data.
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The oceans in their expanse cover, seven - tenths of the Earth surface. Despite being restricted in size, the littoral zone or the intertidal zone (beach) has the greatest variation in environment factors of any marine area .Stemming from this variation ,a treamendous diversity of life, which may be great as or greater than that found in the more extensive sub tidal habits exist in this realm. the study beaches harbour diverse and abundant assemblage of marine organisms. Besides macro funna, microscopic organisms belonging to the lower and higher invertebrate taxa profusely inhabit these beaches. The ecological realm where these animals exist is known as the interstitial environment, which in principle includes the pore spaces in between the sand grains containing copious supply of nutrient rich oxygenated seawater. An astonishing diversity of taxa could be found within the interstitial fauna.
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Globally most of the conventional fish stocks have reached a state of optimum exploitation or even over-exploitation; efficient utilization of non-conventional resources is necessary to meet the supply-demand gap for protein supply. Mesopelagic fishes can be considered as one such promising resource for the future, if appropriate harvest and post-harvest technologies are developed. Increasing human population and increasing demand for cheaper food fishes has made myctophids a possible potential resource for future exploitation and utilization. Earlier studies indicated the abundance of Diaphus spp. in the eastern and northeastern Arabian Sea. The present study also indicates the dominance of Diaphus spp. in the deep sea trawling grounds of south west coast of India. Commercial viability of the myctophid fishing in the Indian waters has to be worked out. The present catch estimation is based on the Stratified Random Sampling Method from the landing data. As the coverage of sampling area was limited and the gear efficiency was not standardized, the data generated are not precise. A counter check for the estimates is also not possible due to the absence of comparable works in the study area. Fish biomass estimation by acoustics survey coupled with direct fishing would only confirm the accuracy of estimates. Exploratory surveys for new fishing areas to be continued, for gathering the distribution, abundance, biological and ecological data and map the potential fishing ground on a GIS platform and the data should be provided to the commercial entrepreneurs. Generally non-conventional and non-targeted resources are under low fishing pressure and exploitation rates. Low values of fishing mortality and exploitation rates indicate that removal from the stock by fishing was only nominal from the present fishing grounds. The results indicate that the stock is almost at virgin state and remains grossly underexploited. Since the extent of distribution and abundance of the stock in the ecosystem remains to be ascertained, sustainable yield could not be estimated. Also the impact of myctophids harvest, on other commercially important fishes, has to be studied.
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Geographically, Taiwan is an Island and situated in the northeast of Asia, on the western side of the Pacific Basin, at the southeast of main China, south of Japan, and north of the Philippines. The main topographic character is the longitudinally oriented mountainous area. More than 200 peaks rise above 3000 m. They departed Taiwan into two lowland areas, an eastern and western plain. Taiwan is departed into subtropical (north area) and tropical zone (south area), which have a warm and humid climate, due to the Tropic of Cancer passing through. The average annual temperature in the lowland amounts to 28°C (7~38°C). The temperate climate also presents in the mountainous areas. The tropical typhoons usually come in summer and bring heavy rain, while the monsoon seasons have an important effect on the regional rainfall distribution. The mean annual rainfall of Taiwan is about 2600 mm (1000~6700 mm); the mountainous areas receive more rain than the lowlands. In Taiwan, according to different temperature and vegetation, the ecological environments were given rise to vertical biotic zonations, and form five major types: highland snowfield, highland meadow, coniferous forest, deciduous forest, and tropical forest. Six National Parks in Taiwan are located in the mountainous areas, in the north, the south, and on Jinmen Island. The National Parks represent about 8.4% of the country area. In this study, the collection sites are situated in Yangmingshan, Shei-Pa, Yushan, and Kenting National Park. Due to the island isolation, the proportions of endemic species are great in Taiwan, which also presents a high biodiversity. There are 4255 species of vascular plants including 1133 endemic. 5936 species in 1276 genera of fungi are hitherto reported in Taiwan. Among them, 233 Corticiaceae species were recorded, over one third (79 species) of them are known only from Taiwan. The first fungal report in Taiwan is about Phytophthora cyperi, published by the Japanese researcher T. Kawakami in 1904. Therefore, the history of research about fungi in Taiwan is more than one hundred years old. An eminent Japanese mycologist K. Sawada made an intensive survey from 1919 to 1959, and reported 2464 fungi species in his eleven volumes of “Descriptive Catalogue of Formosan Fungi”. However, only a few species (21 species in 9 genera) of Corticiaceae were recorded. From 1973, Chen and Lin resumed the study on Corticiaceae, and also some other foreign mycologists contributed for this field after 1980. The German research group lead by Franz Oberwinkler from Tübingen University collected in Taiwan several times. They published a number of new species and new records. Since 1989, S. H. Wu, a Taiwanese mycologist, has published a great amount of reports on corticioid fungi from Taiwan. Corticioid fungi were made up by the large and heterogeneous unnatural family Corticiaceae and other resupinate fungi belonging to other natural families in the Agaricomycetes. Molecular studies have shown that corticioid genera are distributed across all major clades of Agaricomycetes indicating that the corticioid fungi represent a polyphyletic group. They have resupinate fruitbodies and similar habitats. Species are characterized by simple fruitbody, more or less effused, and present smooth, porioid, grandinioid to odontioid hymenial surface. The fruitbodies are differently colored and usually soft to tough. Most of the Corticiaceae species are wood-saprobic organisms and gain the energy from the decomposing of wood-substrate such as cellulose or lignin. Materials for this study were collected by the author and other mycologists in Taiwan during surveys in April and May 1996, and March 2007, using the spring season with its high humidity and warm climate which are optimal conditions for the development of fungi. For assembling, the convenience sampling method was used in this study. This approach was chosen because it enables to detect a high biodiversity in a short time, and also to find species with rare or patchy distribution. The collecting sites from the North to the South include four National Parks and some preserved forests. They cover many different habitats such as low lands and high mountains. Fresh specimens were dried and analysed with a light microscope. 265 specimens belonging to Corticiaceae were studied in this research. Among them, 50 species in 21 genera including 11 new records and 10 new species were described with text and drawing. Four new species are belonging to Hyphodontia (H. sp. nov. 1, H. sp. nov. 2, H. sp. nov. 3, and H. sp. nov. 4), four to Schizopora (Sch. sp. nov. 1, Sch. sp. nov. 2, Sch. sp. nov. 3, and Sch. sp. nov. 4), one in Trechispora (T. sp. nov. 1), and one in Tubulicrinis (T. sp. nov. 1). Species recorded as new are Aleurodiscus amorphus, Botryohypochnus isabellinus, Hyphodontia cineracea, Hyphodontia palmae, Hypochnicium vellereum, Merulius tremellosus, Metulodontia nivea, Paullicorticium ansatum, Phlebia radiata, Phlebiella ardosiaca, and Xylobolus frustulatus. Besides, Botryohypochnus, Merulius, Metulodontia, Paullicorticium, and Xylobolus are also newly recorded genera in Taiwan. The genus Hyphodontia presents the highest diversity with 20 out of 50 species recorded. The second important genus is Hyphoderma, however with only 5 species. This indicates that Hyphodontia and Hyphoderma have a higher ability to develop in variable environments and approximately shows the predominance of these two genera in Taiwanese Corticiaceae. There are 11 new records out of the 50 species recorded, representing 22%. Some species, e.g. Hypochnicium vellereum and Paullicorticium ansatum were in the past recorded only in Europe and North America with cold and temperate climate. The samples of them are for the first time found in the subtropical belt, and display some difference from those of temperate regions. These collections should be molecularly investigated to clarify if they represent the same species of temperate areas. Patchily distributed species, for example Phlebiella ardosiaca, previously known only in Europe, and Hyphodontia palmae collected only in Brazil, were first recorded in different continents. Two possibilities are indicated by these new records: they are worldwide species but very rare to be found, or the Taiwanese specimens are taxonomically different. More survey from other continents and molecular study for these collections should be done in the future to solve this question. The distribution of Corticiaceae in Taiwan presents the variations in the north, central, and south areas and shows the diversity in lowlands and high mountains. The results of this study provide the evidence that the temperate Corticiaceae species displays a wider distribution. Subtropical and tropical taxa probably have also high dispersal capacities, and could possibly be found in the future in neighboring areas such as China, Japan, Korea or South Asia, but this needs further researches. In the total of 50 species, 10 new taxa were described in this study, giving about 20%. Some new species (e.g. Hyphodontia sp. 1, Hyphodontia sp. 2, and Hyphodontia sp. 3) are very similar to known species (Hyphodontia sambuci and Hyphodontia formosana), and the distinctive characters of Schizopora sp. nov. 1 are intermediate between those of Schizopora paradoxa and Hyphodontia flavipora. Thus, these small differences between the new and known species, suggest that the speciation occurred when the fungi migrated into Taiwan, due to the high diversity of environment, and amounts of the endemic plants. Taiwan is an intermediate place for the south (tropical) fungal species to migrate and adapt to north (temperate) regions. The middle and high altitude environments in Taiwan offer good conditions for the fungal speciation and possibly the occurrence of physiological changes to adapt to the temperate climate. Thus Taiwan has an important position for the biogeography of Asia mycobiota. 5936 known species in Taiwan represent about only 20% of the estimated number (24000) of Taiwanese fungal taxa. In this study, the findings (22% new records and 20% new species) indicate that amounts of unknown fungi species are expected in Taiwan. The lack of knowledge indicates that many new species are awaiting description, and fungal survey in Taiwan remains in a Pioneer phase. The last three wide surveys of Corticiaceae researches took place 20 years before this study (Chen & Lin 1977, Lin & Chen 1989, Wu 1990). After previous important contributions, the present taxonomic study comprising 21 genera is the most extensive on Corticiaceae of Taiwan.
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The basic idea behind improving local food security consists of two paths; first, accessibility (price, stock) and second, availability (quantity and biodiversity); both are perquisites to the provision of nutrients and a continuous food supply with locally available resources. The objectives of this thesis are to investigate if indigenous knowledge still plays an important role in traditional farming in the Minangkabau`s culture, thus supporting local food security. If the indigenous knowledge still plays a role in food culture in the Minangkabau`s culture which is linked to the matrilineal role and leads to a sound nutrition. Further, it should be tested if marantau influences traditional farming and food culture in Minangkabau`s, and if the local government plays a role in changing of traditional farming systems and food culture. Furthermore this thesis wants to prove if education and gender are playing a role in changing traditional farming system and food culture, and if the mass media affects traditional farming systems and food culture for the Minangkabau. The study was completed at four locations in West Sumatera; Nagari Ulakan (NU) (coastal area), Nagari Aia Batumbuak (NAB) (hilly area), Nagari Padang Laweh Malalo (NPLM) (lake area), Nagari Pandai Sikek (NPS) (hilly area). The rainfall ranged from 1400- 4800 mm annually with fertile soils. Data was collected by using PRA (Participatory Rural Appraisal) to investigate indigenous knowledge (IK) and its interactions, which is also combining with in depth-interview, life history, a survey using semi-structured-questionnaire, pictures, mapping, and expert interview. The data was collected from June - September 2009 and June 2010. The materials are; map of area, list of names, questionnaires, voices recorder, note book, and digital camera. The sampling method was snowball sampling which resulted in the qualitative and quantitative data taken. For qualitative data, ethnography and life history was used. For quantitative, a statistical survey with a semi-structured questionnaire was used. 50 respondents per each site participated voluntarily. Data was analyzed by performing MAXQDA 10, and F4 audio analysis software (created and developed by Philip-University Marburg). The data is clustered based on causality. The results show that; the role of IK on TFS (traditional farming system) shown on NPLM which has higher food crop biodiversity in comparison to the other three places even though it has relatively similar temperature and rainfall. This high food crop biodiversity is due to the awareness of local people who realized that they lived in unfavourable climate and topography; therefore they are more prepared for any changes that may occur. Carbohydrate intake is 100 % through rice even though they are growing different staple crops. Whereas most of the people said in the interviews that not eating rice is like not really eating for them. In addition to that, mothers still play an important role in kitchen activities. But when the agriculture income is low, mothers have to decide whether to change the meals or to feel insecure about their food supply. Marantau yields positive impact through the remittances it provides to invest on the farm. On the other hand, it results in fewer workers for agriculture, and therefore a negative impact on the transfer of IK. The investigation showed that the local government has a PTS (Padi Tanam Sabatang) programme which still does not guarantee that the farmers are getting sufficient revenue from their land. The low agricultural income leads to situation of potential food insecurity. It is evident that education is equal among men and women, but in some cases women tend to leave school earlier because of arranged marriages or the distances of school from their homes. Men predominantly work in agriculture and fishing, while women work in the kitchen. In NAB, even though women work on farmland they earn less then men. Weaving (NPS) and kitchen activity is recognized as women’s work, which also supports the household income. Mass media is not yielding any changes in TFS and food culture in these days. The traditional farming system has changed because of intensive agricultural extension which has introduced new methods of agriculture for the last three decades (since the 1980’s). There is no evidence that they want to change any of their food habits because of the mass media despite the lapau activity which allows them to get more food choices, instead preparing traditional meal at home. The recommendations of this thesis are: 1) The empowerment of farmers. It is regarding the self sufficient supply of manure, cooperative seed, and sustainable farm management. Farmers should know – where are they in their state of knowledge – so they can use their local wisdom and still collaborate with new sources of knowledge. Farmers should learn the prognosis of supply and demand next prior to harvest. There is a need for farm management guidelines; that can be adopted from both their local wisdom and modern knowledge. 2) Increase of non-agricultural income Increasing the non-agricultural income is strongly recommended. The remittances can be invested on non-agricultural jobs. 3) The empowerment of the mother. The mother plays an important role in farm to fork activities; the mother can be an initiator and promoter of cultivating spices in the backyard. Improvement of nutritional knowledge through information and informal public education can be done through arisan ibu-ibu and lapau activity. The challenges to apply these recommendations are: 1) The gap between institutions and organizations of local governments. There is more than one institution involved in food security policy. 2) Training and facilities for field extension agriculture (FEA) is needed because the rapid change of interaction between local government and farmer’s dependent on this agency.
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This survey study aimed at identifying the factors influencing the success of animal husbandry cooperatives in Southwest Iran. Using a questionnaire, the data were collected from 95 managing directors of the cooperatives who were chosen through a multi-stage stratified random sampling method. This study showed an essential need for a systemic framework to analyze the cooperatives’ success. The results showed that the “Honey Bee”, “Cattle (dairy)”, and “Lamb” cooperatives were the most successful among different kinds of the cooperatives. Also, among individual attributes, “interest”, “technical knowledge”, and “understanding the concept of cooperative”; among economic variables, “income” and “current investment”; and among external factors, “market access” have significant correlation with the success while structural variables have no significant relation. Furthermore, among all the factors, four variables (“interest”, “understanding the concept of cooperative”, “market access”, and “other incomes”) can explain the variations of the success.
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Faisalabad city is surrounded by agricultural lands, where farmers are growing vegetables, grain crops, and fodder for auto-consumption and local marketing. To study the socioeconomic impact and resource use in these urban and peri-urban agricultural production (UPA) systems, a baseline survey was conducted during 2009–2010. A total of 140 households were selected using a stratified sampling method and interviewed with a structured questionnaire. The results revealed that 96 % of the households rely on agriculture as their main occupation. Thirty percent of the households were owners of the land and the rest cultivated either rented or sharecropped land. Most of the families (70 %) were headed by a member with primary education, and only 10 % of the household head had a secondary school certificate. Irrigationwater was obtained from waste water (37 %), canals (27 %), and mixed alternative sources (36 %). A total of 35 species were cultivated in the UPA systems of which were 65% vegetables, 15% grain and fodder crops, and 5% medicinal plants. Fifty-nine percent of the households cultivated wheat, mostly for auto-consumption. The 51 % of the respondents grew cauliflower (Brassica oleracea L.) and gourds (Cucurbitaceae) in the winter and summer seasons, respectively. Group marketing was uncommon and most of the farmers sold their produce at the farm gate (45 %) and on local markets (43 %). Seeds and fertilizers were available from commission agents and dealers on a credit basis with the obligation to pay by harvested produce. A major problem reported by the UPA farmers of Faisalabad was the scarcity of high quality irrigation water, especially during the hot dry summer months, in addition to lacking adequate quantities of mineral fertilizers and other inputs during sowing time. Half of the respondents estimated their daily income to be less than 1.25 US$ and spent almost half of it on food. Monthly average household income and expenses were 334 and 237 US$, respectively.
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1. Suction sampling is a popular method for the collection of quantitative data on grassland invertebrate populations, although there have been no detailed studies into the effectiveness of the method. 2. We investigate the effect of effort (duration and number of suction samples) and sward height on the efficiency of suction sampling of grassland beetle, true bug, planthopper and spider Populations. We also compare Suction sampling with an absolute sampling method based on the destructive removal of turfs. 3. Sampling for durations of 16 seconds was sufficient to collect 90% of all individuals and species of grassland beetles, with less time required for the true bugs, spiders and planthoppers. The number of samples required to collect 90% of the species was more variable, although in general 55 sub-samples was sufficient for all groups, except the true bugs. Increasing sward height had a negative effect on the capture efficiency of suction sampling. 4. The assemblage structure of beetles, planthoppers and spiders was independent of the sampling method (suction or absolute) used. 5. Synthesis and applications. In contrast to other sampling methods used in grassland habitats (e.g. sweep netting or pitfall trapping), suction sampling is an effective quantitative tool for the measurement of invertebrate diversity and assemblage structure providing sward height is included as a covariate. The effective sampling of beetles, true bugs, planthoppers and spiders altogether requires a minimum sampling effort of 110 sub-samples of duration of 16 seconds. Such sampling intensities can be adjusted depending on the taxa sampled, and we provide information to minimize sampling problems associated with this versatile technique. Suction sampling should remain an important component in the toolbox of experimental techniques used during both experimental and management sampling regimes within agroecosystems, grasslands or other low-lying vegetation types.
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Bee pollinators are currently recorded with many different sampling methods. However, the relative performances of these methods have not been systematically evaluated and compared. In response to the strong need to record ongoing shifts in pollinator diversity and abundance, global and regional pollinator initiatives must adopt standardized sampling protocols when developing large-scale and long-term monitoring schemes. We systematically evaluated the performance of six sampling methods (observation plots, pan traps, standardized and variable transect walks, trap nests with reed internodes or paper tubes) that are commonly used across a wide range of geographical regions in Europe and in two habitat types (agricultural and seminatural). We focused on bees since they represent the most important pollinator group worldwide. Several characteristics of the methods were considered in order to evaluate their performance in assessing bee diversity: sample coverage, observed species richness, species richness estimators, collector biases (identified by subunit-based rarefaction curves), species composition of the samples, and the indication of overall bee species richness (estimated from combined total samples). The most efficient method in all geographical regions, in both the agricultural and seminatural habitats, was the pan trap method. It had the highest sample coverage, collected the highest number of species, showed negligible collector bias, detected similar species as the transect methods, and was the best indicator of overall bee species richness. The transect methods were also relatively efficient, but they had a significant collector bias. The observation plots showed poor performance. As trap nests are restricted to cavity-nesting bee species, they had a naturally low sample coverage. However, both trap nest types detected additional species that were not recorded by any of the other methods. For large-scale and long-term monitoring schemes with surveyors with different experience levels, we recommend pan traps as the most efficient, unbiased, and cost-effective method for sampling bee diversity. Trap nests with reed internodes could be used as a complementary sampling method to maximize the numbers of collected species. Transect walks are the principal method for detailed studies focusing on plant-pollinator associations. Moreover, they can be used in monitoring schemes after training the surveyors to standardize their collection skills.
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Accurate differentiation between tropical forest and savannah ecosystems in the fossil pollen record is hampered by the combination of: i) poor taxonomic resolution in pollen identification, and ii) the high species diversity of many lowland tropical families, i.e. with many different growth forms living in numerous environmental settings. These barriers to interpreting the fossil record hinder our understanding of the past distributions of different Neotropical ecosystems and consequently cloud our knowledge of past climatic, biodiversity and carbon storage patterns. Modern pollen studies facilitate an improved understanding of how ecosystems are represented by the pollen their plants produce and therefore aid interpretation of fossil pollen records. To understand how to differentiate ecosystems palynologically, it is essential that a consistent sampling method is used across ecosystems. However, to date, modern pollen studies from tropical South America have employed a variety of methodologies (e.g. pollen traps, moss polsters, soil samples). In this paper, we present the first modern pollen study from the Neotropics to examine the modern pollen rain from moist evergreen tropical forest (METF), semi-deciduous dry tropical forest (SDTF) and wooded savannah (cerradão) using a consistent sampling methodology (pollen traps). Pollen rain was sampled annually in September for the years 1999–2001 from within permanent vegetation study plots in, or near, the Noel Kempff Mercado National Park (NKMNP), Bolivia. Comparison of the modern pollen rain within these plots with detailed floristic inventories allowed estimates of the relative pollen productivity and dispersal for individual taxa to be made (% pollen/% vegetation or ‘p/v’). The applicability of these data to interpreting fossil records from lake sediments was then explored by comparison with pollen assemblages obtained from five lake surface samples.
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The use of social network sites (SNS) has become very valuable to educational institutions. Some universities have formally integrated these social media in their educational systems and are using them to improve their service delivery. The main aim of this study was to establish whether African universities have embraced this emerging technology by having official presence on SNS. A purposive sampling method was used to study 24 universities from which data were obtained by visiting their official websites and following the official links to the most common SNS.
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We conducted a multi-stage household cluster survey to calculate hepatitis B vaccine coverage among children 18-30 months of age in 27 Brazilian cities. Hepatitis B vaccine is administered at birth, 1 month and 6 months of age by Brazil`s national immunization program. Among 17,749 children surveyed, 40.2% received a birth dose within one day of birth, 94.8% received at least one dose of hepatitis B vaccine, and 86.7% completed the three-dose series by 12 months of age. Increased coverage with the birth dose and administration of hepatitis B in combination with diphtheria-tetanus-pertussis-Haemophilus influenzae type b antigens could improve protection against hepatitis B. (C) 2009 Elsevier Ltd. All rights reserved.
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Com vários propósitos, inclusive o de redução de custos e o de facilitar a obtenção das informações desejadas pelo usuário, muitas empresas prestadoras de serviços ao consumidor adotam em suas CATs (Centrais de Atendimento Telefônico) recursos tecnológicos de automação da interação. Examinando-se sob a ótica dos usuários das CATs, estes poderão ter expectativas sobre o serviço que encontrarão e manifestar preferências com relação aos recursos de interação automática. As CATs, ao utilizarem tecnologias de automação da interação, podem estar ou não satisfazendo as expectativas e as preferências dos usuários. Para a determinação de argumentos que suportem as proposições levantadas durante a revisão bibliográfica sobre o tema, realizou-se uma pesquisa dividida em três partes: a) um focus group com alguns usuários de CATs; b) um estudo de campo com usuários de CATs; c) entrevistas com especialistas (levantamento de experiência). Com a técnica Análise de Preferência, propõe-se um modelo das preferências dos usuários em relação ao atendimento automático em CATs. Esse modelo, em princípio, não é generalizável devido às características do processo de amostragem utilizado nesse estudo exploratório. Determinaram-se três grupos distintos de usuários, de acordo com a similaridade entre suas preferências. Determinaram-se usos da tecnologia de atendimento automático que estão em sintonia com as preferências dos usuários. Finalmente, usando os conceitos do Balanced Scorecard, propõe-se um modelo de avaliação gerencial para o uso da tecnologia de atendimento automatizado nas Centrais de Atendimento Telefônico das empresas prestadoras de serviços ao consumidor.
Resumo:
Obesity is currently considered a public health problem and there has been growing interest in the study of various aspects related to this infirmity such as: epidemiology, diagnosis, treatment, prevention and others. Thus, the purpose of this study was to determine the prevalence of weight excess and overweight in preschoolers in Natal, Brazil and relate them to variables such as gender, age, type of school (public or private) and zones of the city (east/south and north/west). This is a transversal study, carried out in Natal, Brazil between August and September 2004, in 20 public and 20 private schools/day care centers selected by the systematic sampling method. We measured the weight and height of 3721 students between the ages of 2 and 6 years. The children were stratified, according to age, into age group 1 (2 to 4 years) and age group 2 (5 and 6 years) and according to the region of the school, into north/west and east/south zones, the regions with the smallest and highest quality of life indices in the city, respectively. Children were considered to have weight excess when BMI ≥ 85th percentile, including those with BMI ≥ 95th percentile and overweight when BMI ≥ 95th percentile. The prevalence of weight excess was 26.5%, and of overweight 12.4%. There was greater prevalence of weight excess in the private schools and in the east/south zones. Overweight displayed the same epidemiologic profile, with a greater prevalence in private schools and in the east/south zones. The prevalence of weight excess in preschoolers in Natal, Brazil is high and is related, above all, to private schools and to those located in the highest quality of life areas. Therefore, prevention programs should be implanted in elementary schools in order to decrease weight excess and possible associated co-morbidities. This research project met the norms established by PPGCSa/UFRN and aimed at promoting the interrelation between different researchers and between different fields of knowledge, using multi and interdisciplinary concepts. This study was enriched by the interaction between the following professionals: pediatrician, pediatric gastroenterologist and physician nutrition specialist, pediatric endocrinologist, epidemiologist and biostatistician