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Sampling Methodology (sampling + methodology)
Selected AbstractsPutting the meio- into stream ecology: current findings and future directions for lotic meiofaunal researchFRESHWATER BIOLOGY, Issue 1 2000A. L. Robertson Summary 1There is a paucity of research on epigean freshwater lotic meiofauna. This may result from a previous emphasis on interstitial (groundwater and hyporheic) meiofauna and/or a reliance on sampling methodologies in lotic systems which are inappropriate for meiofauna. 2Meiofauna contribute much to the diversity of lotic ecosystems. Species lists for seven streams reveal that meiofauna contribute 58,82% of total species numbers, with rotifers and chironomids dominating most systems. The absence of taxonomic keys for most meiofaunal taxa in large areas of the world precludes a wider analysis of their contribution to lotic diversity and an assessment of biogeographical patterns and processes. 3The trophic and functional role of meiofauna in lotic ecosystems is unclear. There are few estimates of meiofaunal production in freshwaters and biomass spectra have produced conflicting results for lotic meiofauna. Present static estimates suggest that the contribution of meiofauna to lotic productivity and biomass is small to moderate, but further studies incorporating a temporal component may provide a more realistic picture of the total contribution of meiofauna to biomass size spectra. 4Meiofauna differ from macroinvertebrates in several respects apart from size and conceptual models for lotic ecosystems should include all metazoans if they are to be truly representative. 5Information on the basic ecology of certain lotic meiofauna (i.e. nematodes, tardigrades, microturbellarians) is urgently required. For those groups whose distributional patterns are better understood (e.g. microcrustaceans), the mechanisms underpinning these patterns should be explored. It is essential that the importance of meiofauna is recognised by lotic ecologists; the only realistic way forward is for greater collaboration among meiofaunal ecologists and taxonomists and other lotic scientists. [source] Comparative analysis of the conformational profile of substance P using simulated annealing and molecular dynamicsJOURNAL OF COMPUTATIONAL CHEMISTRY, Issue 16 2004Francesc J. Corcho Abstract The present study describes an extensive conformational search of substance P using two different computational methods. On the one hand, the peptide was studied using the iterative simulated annealing, and on the other, molecular dynamics simulations at 300 and 400 K. With the former method, the peptide was studied in vacuo with a dielectric constant of 80, whereas using the latter study the peptide was studied in a box of TIP3P water molecules. Analysis of the results obtained using both methodologies was carried out using an in-house methodology using a cluster analysis method based on information theory. Comparison of the two sampling methodologies and the different environment used in the calculations is also analyzed. Finally, the conformational motifs that are characteristic of substance P in a hydrophilic environment are presented and compared with the experimental results available in the literature. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1937,1952, 2004 [source] Floating limb behaviors and self-biting are associated in laboratory monkeysAMERICAN JOURNAL OF PRIMATOLOGY, Issue 8 2010Kathy L. Bentson Abstract Early descriptions of floating limb behaviors in monkeys were associated with isolation rearing, a practice that ended more than two decades ago. The present authors named various forms of behaviors in which a leg is elevated for no apparent reason: "Floating Limb Suite" (FLS). Floating limb behaviors, identified in laboratory monkeys at the Washington National Primate Research Center (WaNPRC), consist of two subcategories distinguished by whether monkeys seem to react to the elevated leg or ignore it. Given the past association of isolation rearing with both self-biting (SB) and floating limb, the investigators predicted that SB and FLS would be associated in monkeys not reared in isolation. The investigators tracked, over a period of 3 years, the presence of FLS and SB in macaques (Macaca nemestrina, M. fascicularis, M. mulatta) and Papio cynocephalus at WaNPRC. SB and both subcategories of FLS occurred in mother-reared and surrogate-peer-nursery-reared monkeys. We analyzed presence of FLS, the two subcategories of FLS, and SB in 1,117 macaques monitored for up to 3 years, and 781 macaques observed for 8,min of structured data collection. The Papio sample size was insufficient for statistical analysis. Both sampling methodologies found FLS and FLS subcategories to be associated with SB. Nearly half the monkeys only engaging in seemingly harmless nonreactive forms of FLS also performed the potentially injurious behavior of self-biting. The positive association between FLS and SB suggests that monkeys exhibiting one of these behaviors are at a heightened risk for developing the other. One impediment to studying floating limb behaviors is lack of consensus on definitions. This study defined seven forms of apparently functionless elevated limb behaviors. Continued research on factors associated with floating limb behaviors across demographic groups and settings may provide insights into the etiology and treatment of self-biting. Am. J. Primatol. 72:725,733, 2010. © 2010 Wiley-Liss, Inc. [source] Real-time quadrupole mass spectrometer analysis of gas in borehole fluid samples acquired using the U-tube sampling methodologyGEOFLUIDS (ELECTRONIC), Issue 3 2006B. M. FREIFELD Abstract Sampling of fluids in deep boreholes is challenging because of the necessity of minimizing external contamination and maintaining sample integrity during recovery. The U-tube sampling methodology was developed to collect large volume, multiphase samples at in situ pressures. As a permanent or semi-permanent installation, the U-tube can be used for rapidly acquiring multiple samples or it may be installed for long-term monitoring applications. The U-tube was first deployed in Liberty County, TX to monitor crosswell CO2 injection as part of the Frio CO2 sequestration experiment. Analysis of gases (dissolved or separate phase) was performed in the field using a quadrupole mass spectrometer, which served as the basis for determining the arrival of the CO2 plume. The presence of oxygen and argon in elevated concentrations, along with reduced methane concentration, indicates sample alteration caused by the introduction of surface fluids during borehole completion. Despite producing the well to eliminate non-native fluids, measurements demonstrate that contamination persists until the immiscible CO2 injection swept formation fluid into the observation wellbore. [source] Perceived Maternal Parenting Self-Efficacy (PMP S-E) tool: development and validation with mothers of hospitalized preterm neonatesJOURNAL OF ADVANCED NURSING, Issue 5 2007Christopher R. Barnes Abstract Title.,Perceived Maternal Parenting Self-Efficacy (PMP S-E) tool: development and validation with mothers of hospitalized preterm neonates Aim., This paper is a report of a study to develop and test the psychometric properties of the Perceived Maternal Parenting Self-Efficacy tool. Background., Mothers' perceptions of their ability to parent (maternal parenting self-efficacy) is a critical mechanism guiding their interactions with their preterm newborns. A robust measure is needed which can measure mothers' perceptions of their ability to understand and care for their hospitalized preterm neonates as well as being sensitive to the various levels and tasks in parenting. Methods., Using a mixed sampling methodology (convenience or randomized cluster control trial) 165 relatively healthy and hospitalized mother-preterm infant dyads were recruited in 2003,2005 from two intensive care neonatal units in the United Kingdom (UK). Mothers were recruited within the first 28 days after giving birth to a preterm baby. The Perceived Maternal Parenting Self-Efficacy tool, which is made up of 20 items representing four theorized subscales, was tested for reliability and validity. Results., Internal consistency reliability of the Perceived Maternal Parenting Self-Efficacy tool was 0·91, external/test-retest reliability was 0·96, P < 0·01. Divergent validity using the Maternal Self-Report Inventory was rs = 0·4, P < 0·05 and using the Maternal Postnatal Attachment Scale was rs = 0·31, P < 0·01. Conclusion., The Perceived Maternal Parenting Self-Efficacy tool is a psychometrically robust, reliable and valid measure of parenting self-efficacy in mothers of relatively healthy hospitalized preterm neonates. Although application outside the UK will require further cross-cultural validation, the tool has the potential to provide healthcare professionals with a reliable method of identifying mothers of preterm hospitalized babies who are in need of further support. [source] Predicting future community composition from random soil seed bank sampling , evidence from a drained lake bottomJOURNAL OF VEGETATION SCIENCE, Issue 3 2007Beatrijs Bossuyt Abstract Questions: What is the accuracy and reliability of the commonly used random soil sampling methodology for predicting seedling density, species richness and composition of the emerging seedling community? Location: Lake Kraenepoel, western Belgium. Methods: We compared density, species composition and observed and rarefactioned species richness of the seedling community emerging on a soft water lake bed exposed after drainage with the seedling community germinating in the laboratory from random soil samples in the same plots. Results: Seedling density did not differ between the two methods and there was a significant correlation between seedling density on the exposed lake bed and in the soil samples. This indicates that future seedling density can be reliably predicted based on soil sampling, in particular for the most abundant species. The most frequently occurring and abundant species among the seedlings in the soil samples were also the most frequent and abundant species germinating on the exposed lake bed. In contrast, species richness was much higher on the exposed lake bed than in the soil samples, and this difference was still significant for annual species after correction for differences in sampling intensity by rarefaction. We found no correlation between the number of species retrieved by the two methods. Although seedlings of rare and target species emerged on the lake bed, random soil sampling clearly failed to detect seeds of most of these species. Conclusions: Random soil sampling at a commonly used intensity and using the standard germination conditions can accurately predict future total seedling density and the density of the most abundant species. However, the method is not reliable for predicting the probability of establishment of populations of uncommon species. When executing a seed bank study, sampling intensity and germination conditions need to be adapted to the nature and the level of detail of the research question to be answered. [source] Carbon stock assessment and soil carbon management in agricultural land-uses in ThailandLAND DEGRADATION AND DEVELOPMENT, Issue 3 2008N. Gnanavelrajah Abstract The organic carbon pool in agricultural land-uses is capable of enhancing agricultural sustainability and serving as a potential sink of atmospheric carbon dioxide. A study was carried out to estimate and map carbon stock of different agricultural land-uses in a sub-watershed of Thailand and to assess the land-use sustainability with respect to carbon management. A quadrat sampling methodology was adopted to estimate the biomass and its carbon content of 11 different land-uses in the study area. Existing soil data were used to calculate the soil carbon. GIS was used for integrating biomass carbon, soil carbon and carbon stock mapping. Roth carbon model was used to project the soil carbon of present land-uses in the coming 10 years and based on which the sustainability of land-uses was predicted. The total carbon stock of agricultural land-uses was estimated to be 20·5,Tg, of which 41·49 per cent was biomass carbon and 58·51 per cent was soil carbon. Among the land-uses, para rubber had the highest average biomass C (136·34,Mg,C,ha,1) while paddy had the lowest (7·08,Mg,C,ha,1). About four-fifths of agricultural land-uses in the watershed are sustainable in maintaining the desired level of soil carbon in coming 10 years while one-fifths are unstable. Such information on carbon stock could be valuable to develop viable land-use options for agricultural sustainability and carbon sequestration. Copyright © 2007 John Wiley & Sons, Ltd. [source] Abundance and distribution of endangered Franciscana dolphins in Argentine waters and conservation implicationsMARINE MAMMAL SCIENCE, Issue 1 2010Enrique A. Crespo Abstract This is the first study in Argentine waters on the abundance of the threatened Franciscana dolphin, Pontoporia blainvillei. During 2003,2004 we carried out 17 aerial surveys using line transect sampling methodology. We observed 101 Franciscanas in 71 sightings. In northern areas density was estimated at 0.106 individual/km2. Density was lower in southern areas (0.055/km2) and declined with depth beyond 30-m isobaths (0.05/km2). A correction factor for submerged dolphins was applied to density and then extrapolated to the strip between the coastline and the 30-m isobath. Abundance in the northern area was estimated at 8,279 (4,904,13,960) individuals, while in the southern area it was estimated at 5,896 (1,928,17,999) individuals. Considering an annual mortality of about 500,800 individuals, about 3.5%,5.6% of the stock may be removed each year by the fishery and over the 2% recommended by the International Whaling Commission (IWC) and may not be sustainable by the population. Higher densities in coastal areas make Franciscanas more vulnerable to coastal fishing camps, which increased mortality in recent years. A remarkable finding was that while density decreases to the south, values of catch per unit effort (CPUE) increases, indicating different catchability of dolphins between areas. [source] | |||||||||||||