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Sampling Procedure (sampling + procedure)
Selected AbstractsIntegrated Sampling Procedure for Metabolome AnalysisBIOTECHNOLOGY PROGRESS, Issue 5 2006Jochen Schaub Metabolome analysis, the analysis of large sets of intracellular metabolites, has become an important systems analysis method in biotechnological and pharmaceutical research. In metabolic engineering, the integration of metabolome data with fluxome and proteome data into large-scale mathematical models promises to foster rational strategies for strain and cell line improvement. However, the development of reproducible sampling procedures for quantitative analysis of intracellular metabolite concentrations represents a major challenge, accomplishing (i) fast transfer of sample, (ii) efficient quenching of metabolism, (iii) quantitative metabolite extraction, and (iv) optimum sample conditioning for subsequent quantitative analysis. In addressing these requirements, we propose an integrated sampling procedure. Simultaneous quenching and quantitative extraction of intracellular metabolites were realized by short-time exposure of cells to temperatures ,95 °C, where intracellular metabolites are released quantitatively. Based on these findings, we combined principles of heat transfer with knowledge on physiology, for example, turnover rates of energy metabolites, to develop an optimized sampling procedure based on a coiled single tube heat exchanger. As a result, this sampling procedure enables reliable and reproducible measurements through (i) the integration of three unit operations into a one unit operation, (ii) the avoidance of any alteration of the sample due to chemical reagents in quenching and extraction, and (iii) automation. A sampling frequency of 5 s,1 and an overall individual sample processing time faster than 30 s allow observing responses of intracellular metabolite concentrations to extracellular stimuli on a subsecond time scale. Recovery and reliability of the unit operations were analyzed. Impact of sample conditioning on subsequent IC-MS analysis of metabolites was examined as well. The integrated sampling procedure was validated through consistent results from steady-state metabolite analysis of Escherichia coli cultivated in a chemostat at D = 0.1 h,1. [source] Sampling Procedures for Coordinating Stratified Samples: Methods Based on MicrostrataINTERNATIONAL STATISTICAL REVIEW, Issue 3 2008Desislava Nedyalkova Summary The aim of sampling coordination is to maximize or minimize the overlap between several samples drawn successively in a population that changes over time. Therefore, the selection of a new sample will depend on the samples previously drawn. In order to obtain a larger (or smaller) overlap of the samples than the one obtained by independent selection of samples, a dependence between the samples must be introduced. This dependence will emphasize (or limit) the number of common units in the selected samples. Several methods for coordinating stratified samples, such as the Kish & Scott method, the Cotton & Hesse method, and the Rivière method, have already been developed. Using simulations, we compare the optimality of these methods and their quality of coordination. We present six new methods based on permanent random numbers (PRNs) and microstrata. These new methods have the advantage of allowing us to choose between positive or negative coordination with each of the previous samples. Simulations are run to test the validity of each of them. Résumé Le but de la coordination d'échantillons est de maximiser ou minimiser le recouvrement de plusieurs échantillons à l'intérieur d'une population qui évolue au fil des temps. Pour effectuer une coordination, la sélection d'un nouvel échantillon dépendra donc des échantillons précédemment tirés. Afin d'obtenir un recouvrement plus fort ou plus faible que celui fourni par des tirages indépendants, une dépendance entre les échantillons doit être introduite. Cette dépendance va augmenter ou limiter le nombre d'unités communes à tous les échantillons sélectionnés. Plusieurs méthodes pour coordonner des échantillons stratifiés ont déjàété développées. Parmi eux les méthodes de Kish and Scott, de Cotton and Hesse, et de Rivière sont présentées en détail. En utilisant des simulations, on compare l'optimalité et la qualité de la coordination pour chacune de ces trois méthodes. On présente six nouvelles méthodes basées sur l'utilisation de nombres aléatoires permanents et des microstrates et on essaye de les valider à l'aide des simulations. [source] Pitfalls in fine needle aspiration cytology,CYTOPATHOLOGY, Issue 4 2003Svante R. OrellArticle first published online: 22 JUL 200 A review of pitfalls encountered in fine needle aspiration cytology (FNAC) of all organs and tissues and based mainly on the author's 35-year experience of diagnostic FNAC in clinical practice is presented. Diagnostic difficulties are usually related to deviations from common cytological criteria that may occur in some lesions. Others are due to the effects of the sampling procedure or of the preparation of samples. A few basic rules are proposed, which may help to avoid some of the diagnostic pitfalls. [source] Comparison of conventional Papanicolaou smears and fluid-based, thin-layer cytology with colposcopic biopsy control in central Italy: A consecutive sampling study of 461 casesDIAGNOSTIC CYTOPATHOLOGY, Issue 1 2009Siavash Rahimi M.D. Abstract The aim of this study was to compare the cytologic diagnosis and specimen adequacy of conventional Papanicolaou (CP) and fluid-based, thin-layer [ThinPrep (TP), Cytyc, Boxborough, MA] cervical cytology in a population from central Italy. CP and TP samples were collected simultaneously using a consecutive sampling method on women presenting for cervical screening. Colposcopy was performed as clinically indicated, and biopsy results were compared with cytologic diagnoses. Among the 461 patients included in the study, 413 were negative at both CP and TP, 9 had unsatisfactory results at both tests and 39 patients presented abnormal results at CP, TP or both. Cohen's Kappa was 0.77 showing good agreement between CP and TP test results. Histological data were available for 20 (51.28%) of the 39 patients with at least one positive test. Among the 13 patients with HSIL at histology, 7 had HSIL at CP (sensitivity 53.85%) and 5 at TP (sensitivity 38.46%). For all three patients with squamous cell carcinoma (SCC) at histology, CP and TP had shown the same diagnosis (sensitivity 100%). The positive predictive values were 33.33% for CP and 25.0% for TP regarding the LSIL diagnosis and 100% for both CP and TP regarding HSIL and SCC diagnoses. Our results may be influenced by the consecutive sampling procedure. Diagn. Cytopathol. 2009. © 2008 Wiley-Liss, Inc. [source] A pleasing consequence of Norway rat eradication: two shrew species recoverDIVERSITY AND DISTRIBUTIONS, Issue 3 2005Michel Pascal ABSTRACT Four to 10 years after the successful eradication of the Norway rat (Rattus norvegicus) from three islands of the Sept,Îles Archipelago and one in the Molène Archipelago (Brittany, France), the abundance index of the lesser white-toothed shrew (Crocidura suaveolens) increased by factors of 7,25, depending on the island and the year. Moreover, in the same region, the abundance index of the greater white-toothed shrew (Crocidura russula) on Tomé Island increased by factors of 9 and 17, one and two years after the Norway rat eradication, respectively. The maximum variation of the abundance index for the lesser white-toothed shrew during seven years on the rat-free island of Béniguet in the same region was a factor of only 2.5. Moreover, the distribution of the lesser white-toothed shrew on Bono island, restricted before the eradication to two steep areas with few rats, increased and encompassed virtually the entire island four years after rats disappeared. These results suggest strong detrimental interactions between the introduced Norway rat and the two Crocidura shrew species on temperate oceanic islands. However, our data do not indicate the ecological mechanisms at work in these interactions. The main reason this shrew recovery was detected after rat eradication was the inclusion in the eradication protocol of the evaluation of impacts on the local biota of eliminating alien species. The rigor of the sampling procedure was also crucial to this discovery. This example demonstrates that an eradication operation can be extremely useful for both scientists and managers if it is planned as a research project. [source] Does smoking in adolescence affect body mass index, waist or height?ADDICTION, Issue 9 2007Findings from a longitudinal study ABSTRACT Aim To assess the effect of smoking uptake on body mass index (BMI), waist circumference and height during adolescence. Design Five-year longitudinal study. Setting Thirty-six schools in South London, England, selected by a stratified random sampling procedure designed to ensure ethnic and socio-economic diversity. Participants A total of 5863 students took part in the HABITS (Health and Behaviour in Teenagers) Study between 1999 and 2003. Measurements Self-reported smoking behaviour, saliva cotinine concentrations and measured weight, waist circumference and height were obtained, along with information on gender, ethnicity, socio-economic deprivation, pubertal status, self-reported exercise and dieting. Students were examined annually from school year 7 (ages 11,12) to year 11 (ages 15,16), with response rates ranging from 74 to 84%. A total of 2665 never smokers at year 7 with complete data for years 7 and 11 were included in the analyses. Findings Adjusting for year 7 BMI and other potential confounders, regular smokers (more than six cigarettes a week) at year 11 had significantly lower BMI (P = 0.002) than other students. Smokers defined by a cotinine above 15 ng/ml also had lower BMI (P < 0.0001). Waist circumferences were lower in regular smokers (P = 0.014) and cotinine-defined smokers (P < 0.011). No consistent association was found between smoking and height. The adjusted difference in weight between regular smokers and other students amounted to 1.8 kg (95% CI, 0.52,3.17) for an average-height student. Conclusion Taking up regular smoking during adolescence may result in a lower BMI, but the effect is small and of uncertain significance. [source] Epidemiology and Symptomatology of Migraine Among School Children: Denizli Urban Area in TurkeyHEADACHE, Issue 8 2004Mehmet Zencir MD Objective.,This study was aimed at finding the prevalence, associated factors, and symptomatology of migraine among 5 to 8 grades of secondary and 9 to 11 grades of high school children (age range between 11 and 18 years old) in the Denizli urban area in the western part of Turkey. Background.,Data from the developed countries indicate that migraine is the most common cause of recurrent headaches in children. Also, childhood migraine is sufficiently severe to prevent the half of the suffering children from carrying on their usual daily activities. Methods.,A cross-sectional school-based study was conducted between May 2000 and June 2000. There were 2,490 participants selected by a multistage stratified clustered sampling procedure. A validated self-administered questionnaire designed according to the International Headache Society criteria was given to the school children of age between 11 and 18 years. Results.,Overall migraine prevalence was 8.8%; it was 6.7% in boys and 11.0% in girls (OR: 1.7; 95% CI: 1.3 to 2.3). Among girls, the highest prevalence (17.7%) occurred at 15 years of age, but among boys, the highest prevalence (11.9%) occurred at 16 years of age. Of children with migraine, 56.5% had a positive family history, and only 29.1% visited a doctor for headache. Conclusion.,Migraine is a common health problem among school children in Denizli urban area and it often goes underdiagnosed. [source] The Italian Preadolescent Mental Health Project (PrISMA): rationale and methodsINTERNATIONAL JOURNAL OF METHODS IN PSYCHIATRIC RESEARCH, Issue 1 2006Alessandra Frigerio Abstract The Italian preadolescent mental health project (PrISMA , Progetto Italiano Salute Mentale Adolescenti) is the first Italian study designed to estimate the prevalence of mental disorders in preadolescents (10,14 years old) living in urban areas, and to analyse the demographic and biological correlates of emotional and behavioural problems. This paper describes the rationale, methods and the analysis plan of the project. The design of the study used a two-stage sampling procedure, one screening stage of emotional and behavioural problems in a large sample of subjects attending public and private schools and a second stage of diagnostic assessment in a sample including all high scorers and a proportion of low scorers. In the screening stage, parents of preadolescents were asked to fill in the Child Behavior Checklist (CBCL), whereas in the second stage preadolescents and their parents were administered the Development and Well Being Assessment for the assessment of mental disorders together with the Strengths and Difficulties Questionnaire and two scales (C-GAS and HoNOSCA) designed to evaluate the functioning of the preadolescent in different areas. Genetic samples were collected during the screening stage, after parents gave their informed written consent. The findings of this study are expected to allow an adequate planning of interventions for the prevention and the treatment of mental disorders in preadolescence as well as efficient health services. Copyright © 2006 John Wiley & Sons, Ltd. [source] Potential biases in sampling design and interpretation of intra-tooth isotope analysisINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1-2 2003M. BalasseArticle first published online: 30 JAN 200 Abstract An increasing number of studies dealing with environmental and dietary reconstruction involve measurement of intra-tooth variation of isotope ratios. The sampling procedure typically consists of collecting a sequence of horizontal bands perpendicular to the growth axis of the tooth. The objective is to obtain a temporal sequence of the changes recorded in dental tissues during tooth development. This paper examines some issues associated with this sampling strategy and consequences for interpretation of the data. Time resolution is influenced by the pattern and duration of enamel mineralization, in a way that might, however, depend on the species and the tooth analysed. Although it may be impossible to sample discrete amounts of time, a chronological order seems to be respected, which should be well enough when the objective is to detect changes in isotope ratios with time. Absolute data must be interpreted with caution. Such issues do not affect studies of inter-individual variability as long as the sampling procedure applied to the compared specimens is consistent. A new sampling strategy is tested on modern goat teeth, involving drilling in an oblique direction. The results obtained from obliquely drilled samples are very similar to those obtained from the horizontal sampling procedure. More work is still needed to determine the value of alternative sampling strategies. Copyright © 2003 John Wiley & Sons, Ltd. [source] Sampling plan for the coffee leaf miner Leucoptera coffeella with sex pheromone trapsJOURNAL OF APPLIED ENTOMOLOGY, Issue 6 2008T. Bacca Abstract The population density of the coffee leaf miner Leucoptera coffeella (Guérin-Méneville & Perrottet) (Lep., Lyonetiidae) can be estimated using pheromone traps in coffee fields as male capture reflects this pest damage based on previous correlational study. However, the spatial distribution of pheromone traps and their density are necessary to optimize the sampling procedure with pheromone traps. Therefore, the objectives of the present study were to determine the pheromone trap density required per hectare to sample coffee leaf miner populations and to determine the spatial distribution of the males of this pest species. The males were sampled every 8 days in 12 consecutive evaluations. Taylor's power law and frequency distributions were used to recognize the distribution of the male capture data, which followed a negative binomial distribution. A common K was obtained, allowing the establishment of a single conventional sampling plan for the 12 fields investigated. The adjusted sampling plan requires eight traps in an area of 30 ha for a 25% precision error. Kriging-generated maps allowed the simulation of male captures for 8, 12 and 20 traps per 30 ha and the results were compared with those obtained with absolute sampling resulting in R2 -values of 0.30, 0.57 and 0.60 respectively. The traps were able to identify the more highly infested areas within the field and are a precise and efficient tool for sampling populations of L. coffeella. [source] Changes in serum cortisol, metabolites, osmotic pressure and electrolytes in response to different blood sampling procedures in cultured sea bass (Dicentrarchus labrax L.)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2001Marino This study investigated the effect of five sampling procedures on serum cortisol, glucose, total protein, osmolality, Na+, Cl,, K+ and Ca++ concentrations in 2-year-old cultured sea bass (Dicentrarchus labrax L). Mild disturbance caused by rapid removal of fish and brief handling did not induce significant variation in any of the blood parameters investigated. Confinement and crowding elicited a high and significant increase in serum cortisol, glucose, osmolality, Na+, Cl,, and Ca++ concentrations. Exposure to MS 222 (140 mg L,1) significantly increased osmolality, but not ionic concentration. Site of blood withdrawal (cardiac sinuses/caudal vein) had no effect on the concentration of analysed blood constituents, except for K+ levels. Scattered literature of sea bass blood chemistry is reviewed and compared with ,normal' ranges of blood constituents measured in this study. We conclude that it is necessary to select and rigorously execute an opportune blood sampling procedure whenever blood constituents are used as indicators of fish functional state. [source] Biofiltration of nuisance sulfur gaseous odors from a meat rendering plantJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 12 2002Zarook Shareefdeen Abstract This paper presents a case study of a commercial biofilter, treating air streams contaminated with several odorous compounds including dimethyl sulfide, ammonia, methanethiol, hydrogen sulfide and ethylamine. The biofilter is packed with a proprietary wood-based (BIOMIXÔ) medium which is designed to provide a good biological environment, pH buffer capacity, low pressure drop and resistance to compaction. This commercial biofilter treats a contaminated air volume of 15,000 actual cubic feet per minute (acfm) from a meat rendering and wastewater treatment operation with a 30-s empty bed residence time. The case study includes a novel gas sampling procedure and characterization of biofilter air streams through a mobile Fourier transform infrared system and olfactometer analysis. The results confirmed the good distribution of air, moisture and bacterial population across the medium. Four years of consistent performance of this commercial biofilter with >99% removal of 24,500 odor units demonstrates that biofilters can be successfully applied for the removal of highly odorous gaseous sulfur compounds. © 2002 Society of Chemical Industry [source] The role of affective experience in work motivation: Test of a conceptual modelJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 7 2010Myeong-Gu Seo The purpose of this paper was to contribute to understanding of the crucial role of emotion in work motivation by testing a conceptual model developed by Seo, Barrett, and Bartunek (2004) that predicted the impacts of core affect on three behavioral outcomes of work motivation, generative-defensive orientation, effort, and persistence. We tested the model using an Internet-based investment simulation combined with an experience sampling procedure. Consistent with the predictions of the model, pleasantness was positively related to all three of the predicted indices. For the most part, these effects occurred indirectly via its relationships with expectancy, valence, and progress judgment components. Also as predicted by the model, activation was directly and positively related to effort. Copyright © 2009 John Wiley & Sons, Ltd. [source] In-line measurement of a drug substance via near infrared spectroscopy to ensure a robust crystallization processJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2006George X. Zhou Abstract The crystallization of Etoricoxib, a polymorphic compound, has been optimized and controlled by seeding with the desired polymorph at a moderate supersaturation condition. To enhance the process robustness, near infrared spectroscopy (NIRS) has been evaluated as an inline measurement method for the concentration of Etoricoxib prior to seeding in the crystallization process. In this NIRS method, a spectral discriminant analysis based on principal component analysis (PCA) was established to detect the presence of solids produced by premature crystallization, or bubbles in the path of light. Once a spectrum was qualified as that of clear solution, concentration of Etoricoxib was calculated by a NIRS calibration model built with partial least squares (PLS) regression and with offline HPLC analysis as the reference method. This model was accurate with a standard error of cross validation (SECV) less than 1.2 mg/g Etoricoxib and a standard error of prediction (SEP) less than 1.7 mg/g over the concentration range from 50 to 170 mg/g, temperature range from 49 to 65°C, and different sources of materials. In addition, all aspects of the offline HPLC method, especially the sampling procedure, were optimized to provide an accurate reference for NIRS calibration models. The application of this method at a pilot plant has demonstrated its capability of accurately measuring the process concentration of Etoricoxib as well as detecting the presence of solids produced by premature crystallization before seeding. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95:2337,2347, 2006 [source] Influences of adult-onset diabetes on orofacial pain and related health behaviorsJOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 2 2010Bridgett Rahim-Williams MA Abstract Objectives: This study tested the hypothesis that persons with orofacial pain and comorbid adult-onset diabetes will experience greater functional and emotional impact than persons experiencing orofacial pain without diabetes. Methods: A random-digit dialing sampling procedure was used for a disproportionate probability sample of 10,341 persons who were screened for orofacial pain in the past 6 months and diabetes. This paper reports on 1,767 individuals reporting toothache pain and 877 reporting painful oral sores. A structured telephone interview assessed diabetes history, orofacial pain characteristics, oral health-care behaviors, and emotional and functional impacts of orofacial pain. Results: The 6-month point prevalence was 16.8 percent for toothache pain, 8.9 percent for painful oral sores, and 9.6 percent for adult-onset diabetes. Individuals with comorbid orofacial pain and adult-onset diabetes differed significantly on many of the pain characteristics and health behaviors compared with nondiabetic sufferers of orofacial pain. Diabetics were more likely than nondiabetics to have pain every day, to suffer negative emotions associated with pain, to experience disruption of daily activities and sleep, to make an emergency room visit for orofacial pain, and to report the current need for a pain-related health-care visit. Conclusions: Although diabetes is well known to be associated with neuropathic pain, these results indicate that the experience of nociceptive pain is exacerbated by diabetes. Findings have significance for the subjective experience of oral pain, dental-care outcomes, and health-related quality of life associated with oral-health outcomes among individuals with diabetes. [source] Prevalence and Degree of Childhood and Adolescent Overweight in Rural, Urban, and Suburban GeorgiaJOURNAL OF SCHOOL HEALTH, Issue 4 2006Richard D. Lewis The aim of this study was to determine the prevalence of OW and EOW in school-aged youths from 4 regions of Georgia. A 2-stage cluster sampling procedure was performed in 2002, with participation of 4th-, 8th- and 11th-grade students (N = 3114). Measured height and weight were used to determine body mass index (BMI) for age percentiles and data were weighted to estimate population prevalence of OW. A logistic regression model determined predictors of OW. The overall estimate of OW prevalence was 20.2% and highest in males (22.0%), non-Hispanic blacks (21.8%), "other races" (32.4%), and students residing in rural growth (23.7%) and rural decline (23.0%) areas. Overweight prevalence was similar among grades. The overall estimated EOW was 4.3 and highest in males (4.7), other races (5.6), non-Hispanic blacks (5.2), and students from rural growth (5.4) and rural decline (5.0) areas. Sex, race, location, and economic tier were significant predictors (= 0.02) of OW. The prevalence and severity of OW was higher in youths residing in Georgia than nationally. School health professionals, community leaders, and parents should provide support for updated school policies aimed at providing BMI surveillance and a school environment that encourages physical activity and healthy nutrition practices. (J Sch Health. 2006;76(4):126-132) [source] Rapid prenatal diagnosis of aneuploidies and zygosity in multiple pregnancies by amniocentesis with single insertion of the needle and quantitative fluorescent PCRPRENATAL DIAGNOSIS, Issue 8 2003Vincenzo Cirigliano Abstract Objective To investigate amniotic fluid (AF) samples retrieved in multiple pregnancies by single insertion of the needle, for rapid assessment of chromosome copy number, zygosity, and cross-contamination between fetuses, using Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) amplification of highly polymorphic microsatellite markers. Methods Fifty-two multiple pregnancies were selected (47 twins, 5 triplets) and 108 samples of amniotic fluid were sampled between 12 to 20 weeks of gestation (mean 15.5) using the single-needle technique. Aneuploidy screening by QF-PCR amplification of short tandem repeats (STRs) on chromosomes X, Y, 21, 13, and 18 was carried out within 24 h of collection. Owing to the sampling procedure, the eventual presence of contamination between fetuses was also evaluated in every case. Results Normal and aneuploid fetuses were readily identified by QF-PCR. Fetal reduction was made available, for trisomic fetuses, without further waiting for completion of fetal karyotyping. In twin gestations, the ultrasound examination of chorionicity was always in agreement with the molecular assessment of zygosity. Contamination between fetuses due to the sampling procedure with a single puncture was never observed. Conclusion Rapid prenatal diagnosis of aneuploidies by QF-PCR is a sensitive, efficient, and reliable assay. When applied in multiple pregnancies, it has the added value of allowing the assessment of zygosity in all cases, independently of chorionicity and fetal sex. Copyright © 2003 John Wiley & Sons, Ltd. [source] Building anisotropic sampling schemes for the estimation of anisotropic dispersalANNALS OF APPLIED BIOLOGY, Issue 3 2009S. Soubeyrand Abstract Anisotropy, a structural property of dispersal, is observed in dispersal patterns occurring for a wide range of biological systems. While dispersal models more and more often incorporate anisotropy, the sampling schemes required to collect data for validation usually do not account for the anisotropy of dispersal data. Using a parametric model already published to describe the spatial spread of a plant disease, the wheat yellow rust, we carry out a study aimed at recommending an appropriate sampling scheme for anisotropic data. In a first step, we show with a simulation study that prior knowledge of dispersal anisotropy can be used to improve the sampling scheme. One of the main guidelines to be proposed is the orientation of the sampling grid around the main dispersal directions. In a second step, we propose a sequential sampling procedure (SSP) used to automatically build anisotropic sampling schemes adapted to the actual anisotropy of dispersal. The SSP is applied to simulated and real data. The proposed methodology is expected to be adapted easily to any kind of organisms with wind-borne propagule dispersal because it does not require the inclusion of biological features specific of the considered organism. [source] Alternative matrices for cortisol measurement in fishAQUACULTURE RESEARCH, Issue 8 2010Daniela Bertotto Abstract Plasma cortisol is the most commonly used indicator of stress in fish but, as the blood sampling procedure itself can be a source of stress, it would be helpful to measure cortisol using less invasive matrices. It is also necessary to find alternative matrices as stress indicators in dead fish in which blood sampling is impossible. In the present study, we investigated transport stress in three aquaculture species, European sea bass (Dicentrarchus labrax L.), common carp (Cyprinus carpio L.) and rainbow trout (Oncorhynchus mykiss Walbaum), by cortisol determination (radioimmunoassay) in plasma and other matrices (skin mucus, gut content, lateral muscle and caudal fin). Cortisol significantly increased after transport in all species and matrices, except in the sea bass gut content, where it remained unchanged. The three species responded to transport stress by producing different cortisol levels. In conclusion, the significant correlation found between plasma cortisol and most of the other matrices opens up the possibility of using them to evaluate stress in fish: mucus sampling is a less invasive method than blood sampling, and in addition to muscle and fin sampling, it can be used in postmortem fish. [source] General health in Timor-Leste: self-assessed health in a large household surveyAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 4 2009Jaya Earnest Abstract Objective: Timor-Leste is one of the world's newest nations and became a democracy in 2002. Ranked 150 out of 177 in the 2007 UNDP Human Development Index, the country has the worst health indicators in the Asia-Pacific region. The objective of this study was to collect and analyse data on subjectively assessed general health, health service use, migration and mobility patterns. Methods: The data collection involved recording self-reported status of general health using a structured questionnaire. The survey was administered to 1,213 Timorese households in six districts using a multi-stage random cluster sampling procedure. Basic descriptive statistical analyses were performed on all variables with SPSS version 13. Results: More than a quarter (27%) of respondents reported a health problem at the time of the survey. Only approximately half of respondents assessed their health to be good (53%) or average (38%). Barriers reported in the uptake of healthcare services were no felt needed; difficulty in accessing services and unavailability of service. Conclusions: Results reveal that Timor-Leste needs a more decentralised provision of healthcare through primary healthcare centres or integrated health services. Trained traditional healers, who are familiar with the difficult terrain and understand cultural contexts and barriers, can be used to improve uptake of public health services. An adult literacy and community health education program is needed to further improve the extremely poor health indicators in the country. Implications: Key lessons that emerged were the importance of understanding cultural mechanisms in areas of protracted conflict and the need for integrated health services in communities. [source] Integrated Sampling Procedure for Metabolome AnalysisBIOTECHNOLOGY PROGRESS, Issue 5 2006Jochen Schaub Metabolome analysis, the analysis of large sets of intracellular metabolites, has become an important systems analysis method in biotechnological and pharmaceutical research. In metabolic engineering, the integration of metabolome data with fluxome and proteome data into large-scale mathematical models promises to foster rational strategies for strain and cell line improvement. However, the development of reproducible sampling procedures for quantitative analysis of intracellular metabolite concentrations represents a major challenge, accomplishing (i) fast transfer of sample, (ii) efficient quenching of metabolism, (iii) quantitative metabolite extraction, and (iv) optimum sample conditioning for subsequent quantitative analysis. In addressing these requirements, we propose an integrated sampling procedure. Simultaneous quenching and quantitative extraction of intracellular metabolites were realized by short-time exposure of cells to temperatures ,95 °C, where intracellular metabolites are released quantitatively. Based on these findings, we combined principles of heat transfer with knowledge on physiology, for example, turnover rates of energy metabolites, to develop an optimized sampling procedure based on a coiled single tube heat exchanger. As a result, this sampling procedure enables reliable and reproducible measurements through (i) the integration of three unit operations into a one unit operation, (ii) the avoidance of any alteration of the sample due to chemical reagents in quenching and extraction, and (iii) automation. A sampling frequency of 5 s,1 and an overall individual sample processing time faster than 30 s allow observing responses of intracellular metabolite concentrations to extracellular stimuli on a subsecond time scale. Recovery and reliability of the unit operations were analyzed. Impact of sample conditioning on subsequent IC-MS analysis of metabolites was examined as well. The integrated sampling procedure was validated through consistent results from steady-state metabolite analysis of Escherichia coli cultivated in a chemostat at D = 0.1 h,1. [source] Pterygium in Tibetans: a population-based study in ChinaCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 9 2007Peng Lu MD Abstract Purpose:, To describe the prevalence and to identify associated risk factors for pterygium in a Tibetan population at high altitude in Zeku County, China. Methods:, A prospective population-based survey was conducted from October to December 2006. A stratified, clustered, randomized sampling procedure was used to select 2632 Tibetan people aged 40 years and older. Pterygium was diagnosed and graded clinically as grade 1 (transparent), 2 (intermediate) and 3 (opaque). Risks factors associated with pterygium were evaluated with logistic regression models. Results:, From a total of 2632 eligible subjects, 2229 (84.69%) were examined. There were 323 people with pterygium, equivalent to an overall prevalence of 14.49% (95% confidence interval [CI] 13.03,15.95). Pterygium was independently associated with increasing age for persons aged 70,79 years, compared with those aged 40,49 years (odds ratio [OR] 2.0; 95% CI 1.4,2.8), female gender (OR 1.6; 95% CI 1.2,2.0), dry eye symptoms (OR 1.3; 95% CI 1.0,1.7), seldom use of sunglasses/crystal spectacles (OR 4.6; 95% CI 1.9,11.3) or hats (OR 3.6: 95% CI 2.4,5.4), lower education level (<3 years) (OR 1.6; 95% CI 1.1,2.4) and low socioeconomic status (OR 1.9; 95% CI 1.5,2.4). Conclusions:, The prevalence of pterygium in a Tibetan population at high altitude is significantly high, particularly in certain at-risk groups. The primary causative factors are related to ocular sun exposure, which are easily preventable. Public health schemes to address this serious health issue are urgently needed. [source] Caries prevalence in Belgian children: a reviewINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2001J. Vanobbergen A review of epidemiological surveys on dental caries prevalence, published between 1980 and 1999 in Belgian children, was compiled through a literature search. The number of studies performed in Belgium to date is limited. Methodological differences and confounding factors, especially socio-demographic influences, limit national comparisons of caries prevalence data. Although exact comparisons are difficult, data suggests a decline in caries prevalence in 5, 7 and 12 year-old Belgian schoolchildren in the last 20 years. In the primary dentition dmft values have decreased from 2·66 (1981) to 1·38 (1994) in 5-year-olds and from 4·1 (1983) to 2·24 (1996) in 7-year-olds. In 12-year-olds DMFT values in the permanent dentition have decreased from 3·9 (1983) to 1·93 (1994). WHO goals for the year 2000 appear to have been already reached in Flanders, with a recent estimate of 1·93 for DMFT in 12-year-olds and 56% of children being recorded as caries free at the age of 5. Continuing efforts are needed to screen the oral health of different age groups but standardised criteria and sampling procedures should be used if benefits are to be gained from national and international comparison. Data has often been limited to small selected areas and information representing the entire community of Flanders or Wallonia would be of particular value. [source] Stereological comparison of 3D spatial relationships involving villi and intervillous pores in human placentas from control and diabetic pregnanciesJOURNAL OF ANATOMY, Issue 2 2000TERRY M. MAYHEW In human placenta, 3D spatial relationships between villi and the maternal vascular bed determine intervillous porosity and this, in turn, influences haemodynamics and transport. Recently-developed stereological methods were applied in order to examine and quantify these relationships. Placentas were collected after 37 wk from control pregnancies and those associated with maternal diabetes mellitus classified according to duration and severity (White classification scheme). Two principal questions were addressed: (1) are normal spatial arrangements maintained in well-controlled diabetes mellitus? and (2) do arrangements vary between diabetic groups? To answer these questions, tissue sections cut at random positions and orientations were generated by systematic sampling procedures. Volume densities of villi (terminal+intermediate), intervillous spaces and perivillous fibrin-type fibrinoid deposits were estimated by test point counting and converted to global volumes after multiplying by placental volumes. Design-based estimates of the sizes (volume- and surface-weighted volumes) of intervillous ,pores' were obtained by measuring the lengths of point- and intersection-sampled intercepts. From these, theoretical numbers of pores were calculated. Model-based estimates (cylinder model) of the hydraulic diameters and lengths of pores were also made. Second-order stereology was used to examine spatial relationships within and between villi and pores and to test whether pair correlation functions deviated from the value expected for ,random' arrangements. Estimated quantities did not differ significantly between diabetic groups but did display some departures from control values in non-insulin-dependent (type 2) diabetic placentas. These findings support earlier studies which indicate that essentially normal microscopical morphology is preserved in placentas from diabetic subjects with good glycaemic control. Therefore, it is likely that fetal hypoxia associated with maternal diabetes mellitus is due to metabolic disturbances rather than abnormalities in the quantities or arrangements of maternal vascular spaces. [source] Aspects of the population biology of Cephalopholis fulva from the central coast of BrazilJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2009J. N. Araújo Summary Age and size composition samples of Cephalopholis fulva from the central coast of Brazil were collected from research surveys and from line fishery landings between 1997 and 1999. The samples suggest that the submarine banks located further offshore are characterized by having fish larger than those caught in the continental shelf area. Although the oldest specimens were caught in the continental shelf area, only 34.6% of the specimens were older than 10 years as compared to 51.4% in the submarine banks. The observed size and age differences seem to be related to the lower fishing pressure on the submarine banks, although size composition bias resulting from different sampling procedures and different catchability between sites cannot be excluded. A resampling scheme was used to overcome the influences of size composition bias and to generate a three-dimensional plot of parameters as a means to compare the growth between the submarine banks and the continental shelf area; this plot showed no overlap between growth patterns of the two sites. The natural mortality (M) estimate based on the oldest specimen observed was 0.17 year,1. Total mortality (Z) estimated from catch-curve analyses using samples from both areas varied from 0.24 to 0.34 year,1, depending on the age range used. With this level of mortality, the C. fulva stock in the central coast area of Brazil was close to or already at the level of overexploitation in the late 1990s. [source] Changes in serum cortisol, metabolites, osmotic pressure and electrolytes in response to different blood sampling procedures in cultured sea bass (Dicentrarchus labrax L.)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2001Marino This study investigated the effect of five sampling procedures on serum cortisol, glucose, total protein, osmolality, Na+, Cl,, K+ and Ca++ concentrations in 2-year-old cultured sea bass (Dicentrarchus labrax L). Mild disturbance caused by rapid removal of fish and brief handling did not induce significant variation in any of the blood parameters investigated. Confinement and crowding elicited a high and significant increase in serum cortisol, glucose, osmolality, Na+, Cl,, and Ca++ concentrations. Exposure to MS 222 (140 mg L,1) significantly increased osmolality, but not ionic concentration. Site of blood withdrawal (cardiac sinuses/caudal vein) had no effect on the concentration of analysed blood constituents, except for K+ levels. Scattered literature of sea bass blood chemistry is reviewed and compared with ,normal' ranges of blood constituents measured in this study. We conclude that it is necessary to select and rigorously execute an opportune blood sampling procedure whenever blood constituents are used as indicators of fish functional state. [source] Sample Size Determination for Categorical ResponsesJOURNAL OF FORENSIC SCIENCES, Issue 1 2009Dimitris Mavridis Ph.D. Abstract:, Procedures are reviewed and recommendations made for the choice of the size of a sample to estimate the characteristics (sometimes known as parameters) of a population consisting of discrete items which may belong to one and only one of a number of categories with examples drawn from forensic science. Four sampling procedures are described for binary responses, where the number of possible categories is only two, e.g., licit or illicit pills. One is based on priors informed from historical data. The other three are sequential. The first of these is a sequential probability ratio test with a stopping rule derived by controlling the probabilities of type 1 and type 2 errors. The second is a sequential variation of a procedure based on the predictive distribution of the data yet to be inspected and the distribution of the data that have been inspected, with a stopping rule determined by a prespecified threshold on the probability of a wrong decision. The third is a two-sided sequential criterion which stops sampling when one of two competitive hypotheses has a probability of being accepted which is larger than another prespecified threshold. The fifth procedure extends the ideas developed for binary responses to multinomial responses where the number of possible categories (e.g., types of drug or types of glass) may be more than two. The procedure is sequential and recommends stopping when the joint probability interval or ellipsoid for the estimates of the proportions is less than a given threshold in size. For trinomial data this last procedure is illustrated with a ternary diagram with an ellipse formed around the sample proportions. There is a straightforward generalization of this approach to multinomial populations with more than three categories. A conclusion provides recommendations for sampling procedures in various contexts. [source] Circulating matrix metalloproteinase 9 levels in relation to sampling methods, femoral and carotid atherosclerosisJOURNAL OF INTERNAL MEDICINE, Issue 6 2008F. J. Olson Abstract. Objectives., To examine whether circulating levels of matrix metalloproteinase 9 (MMP-9) were associated with ultrasound-assessed intima-media thickness (IMT) and echolucent plaques in the carotid and femoral arteries. To examine preanalytical sources of variability in MMP-9 concentrations related to sampling procedures. Subjects and design., Plasma and serum MMP-9 levels were compared with ultrasound assessed measures of femoral and carotid atherosclerosis, in a cross-sectional study of 61-year-old men (n = 473). Preanalytical sources of variability in MMP-9 levels were examined in 10 healthy subjects. Main outcome measures were circulating levels of MMP-9 in serum and plasma, IMT of the carotid and femoral arteries, and plaque status based on size and echolucency. Setting., Research unit at university hospital. Results., Plasma concentrations of total and active MMP-9 were associated with femoral artery IMT independently of traditional cardiovascular risk factors, and were higher in subjects with moderate to large femoral plaques. Plasma MMP-9 concentration was higher in men with echolucent femoral plaques (P = 0.006) compared with subjects without femoral plaques. No similar associations were found for carotid plaques. MMP-9 concentrations were higher in serum than in plasma, and higher when sampling was performed with Vacutainer than with syringe. MMP-9 levels in serum were more strongly associated with peripheral neutrophil count compared with MMP-9 levels in plasma. Conclusions., Plasma MMP-9 levels were associated with atherosclerosis in the femoral artery, and total MMP-9 concentration was higher in men with echolucent femoral plaques. The choice of sample material and sampling method affect the measurements of circulating MMP-9 levels. [source] EFFECTS OF SAMPLING CONDITIONS ON TEMPORAL PERCEPTION OF BITTERNESS IN YERBA MATE (ILEX PARAGUARIENSIS) INFUSIONSJOURNAL OF SENSORY STUDIES, Issue 3 2004AMALIA CALVIÑO ABSTRACT Time-intensity (TI) methodology and a trained panel were used to characterize the perceived bitterness of Yerba mate (YM) Ilex paraguariensis infusions. Two sampling procedures (sip and spit; sip and swallow) and two conditions for residence time in mouth (free or fixed duration of 5 s until spit or swallow) were evaluated. At a fixed duration the maximum bitterness as well as the time to reach it showed a significant YM concentration dependence. No change on bitterness was observed by swallowing or spitting YM infusions except a larger rate of decay of the response (vr) at spit condition. Dynamic bitterness at free sampling time showed that the decision period to spit or swallow the YM infusion approximately duplicated the fixed one of 5 s. [source] Sampling methods for phlebotomine sandfliesMEDICAL AND VETERINARY ENTOMOLOGY, Issue 2 2000B. Alexander Summary A review is presented of methods for sampling phlebotomine sandflies (Diptera: Psychodidae). Among ,500 species of Phlebotominae so far described, mostly in the New World genus Lutzomyia and the Old World genus Phlebotomus, about 10% are known vectors of Leishmania parasites or other pathogens. Despite being small and fragile, sandflies have a wide geographical range with species occupying a considerable diversity of ecotopes and habitats, from deserts to humid forests, so that suitable methods for collecting them are influenced by environmental conditions where they are sought. Because immature phlebotomines occupy obscure terrestrial habitats, it is difficult to find their breeding sites. Therefore, most trapping methods and sampling procedures focus on sandfly adults, whether resting or active. The diurnal resting sites of adult sandflies include tree holes, buttress roots, rock crevices, houses, animal shelters and burrows, from which they may be aspirated directly or trapped after being disturbed. Sandflies can be collected during their periods of activity by interception traps, or by using attractants such as bait animals, CO2 or light. The method of trapping used should: (a) be suited to the habitat and area to be surveyed, (b) take into account the segment of the sandfly population to be sampled (species, sex and reproduction condition) and (c) yield specimens of appropriate condition for the study objectives (e.g. identification of species present, population genetics or vector implication). Methods for preservation and transportation of sandflies to the laboratory also depend on the objectives of a particular study and are described accordingly. [source] | ||||||||||||||||||||||