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Sample Consisting (sample + consisting)
Selected AbstractsA minimum sample size required from Schmidt hammer measurementsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 13 2009Tomasz Niedzielski Abstract The Schmidt hammer is a useful tool applied by geomorphologists to measure rock strength in field conditions. The essence of field application is to obtain a sufficiently large dataset of individual rebound values, which yields a meaningful numerical value of mean strength. Although there is general agreement that a certain minimum sample size is required to proceed with the statistics, the choice of size (i.e. number of individual impacts) was usually intuitive and arbitrary. In this paper we show a simple statistical method, based on the two-sample Student's t -test, to objectively estimate the minimum number of rebound measurements. We present the results as (1) the ,mean' and ,median' solutions, each providing a single estimate value, and (2) the empirical probability distribution of such estimates based on many field samples. Schmidt hammer data for 14 lithologies, 13,81 samples for each, with each sample consisting of 40 individual readings, have been evaluated, assuming different significance levels. The principal recommendations are: (1) the recommended minimum sample size for weak and moderately strong rock is 25; (2) a sample size of 15 is sufficient for sandstones and shales; (3) strong and coarse rocks require 30 readings at a site; (4) the minimum sample size may be reduced by one-third if the context of research allows for higher significance level for test statistics. Interpretations based on less than 10 readings from a site should definitely be avoided. Copyright © 2009 John Wiley & Sons, Ltd. [source] Caries and dental fluorosis in a western Saharan population of refugee childrenEUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2008José Manuel Almerich-Silla The aim of this study was to investigate the relationship between dental fluorosis and dental caries among western Saharan refugee children. The western Saharan child population is characterized by adverse living conditions, an unbalanced diet, poor oral hygiene habits, and a concentration of fluoride in the drinking water of around 2 p.p.m. (2 mg l,1). A sample consisting of 360 children, 6,7 yr of age, and 212 children, 11,13 yr of age, was obtained from four refugee camps (Smara, Awsard, El-Aaiun, and 27-February) situated in the vicinity of Tindouf (southern Algeria). The children were examined using the World Health Organization criteria for caries diagnosis and Dean's index for fluorosis. The decayed, missing or filled teeth (DMFT) score was 0.48 in the 6,7-yr-old children and 1.69 in the 11,13-yr-old children, with a caries prevalence (DMFT > 0 or decayed and filled primary teeth (dft) > 0) of 47.2% and 63.2%, respectively. Among the 6,7 yr-old children examined, 36.9% were free of fluorosis, 15.6% presented moderate fluorosis, and 7.8% presented severe fluorosis. Among 11,13 yr-old children, only 4.2% were free of fluorosis, 30.2% exhibited moderate fluorosis, and 27.4% presented severe fluorosis. The mean DMFT, decayed permanent teeth (DT), and caries prevalence (DMFT > 0 and DMFT or dft > 0) scores were significantly higher among the children affected by severe fluorosis, suggesting that severe fluorosis might increase the susceptibility to dental caries. [source] Financial Literacy of Young Adults: The Importance of Parental SocializationFAMILY RELATIONS, Issue 4 2010Bryce L. Jorgensen This article tests a conceptual model of perceived parental influence on the financial literacy of young adults. Structural equation modeling was used to test whether (a) parents were perceived to influence young adults' financial knowledge, attitudes, and behaviors and (b) the degree to which young adults' financial attitudes mediated financial knowledge and perceived parental influence on young adults' financial behaviors. A sample consisting of 420 college students participated in the study. Findings by the College Student Financial Literacy Survey (CSFLS) indicated that perceived parental influence had a direct and moderately significant influence on financial attitude, did not have an effect on financial knowledge, and had an indirect and moderately significant influence on financial behavior, mediated through financial attitude. [source] A Mediation Model of Interparental Collaboration, Parenting Practices, and Child Externalizing Behavior in a Clinical SampleFAMILY RELATIONS, Issue 3 2009John Kjøbli The present study examined maternal and paternal parenting practices as mediators of the link between interparental collaboration and children's externalizing behavior. Parent gender was tested as a moderator of the associations. A clinical sample consisting of 136 children with externalizing problems and their families participated in the study. Structural equation modeling was used to test the study hypotheses. Maternal and paternal parenting practices fully mediated the relation between interparental collaboration and externalizing behavior. When the mediated pathways were tested separately, paternal parenting practices functioned as a mediator, whereas maternal parenting practices did not, indicating that the relationship between interparental collaboration, parenting practices and externalizing behavior was moderated by parent gender. The findings suggest that treatments aimed at reducing child externalizing behavior may be strengthened by focusing on interparental collaboration in addition to parenting practices, while also underscoring the need to involve fathers in interventions. [source] Topotactic Conversion Route to Mesoporous Quasi-Single-Crystalline Co3O4 Nanobelts with Optimizable Electrochemical PerformanceADVANCED FUNCTIONAL MATERIALS, Issue 4 2010Li Tian Abstract The growth of mesoporous quasi-single-crystalline Co3O4 nanobelts by topotactic chemical transformation from , -Co(OH)2 nanobelts is realized. During the topotactic transformation process, the primary , -Co(OH)2 nanobelt frameworks can be preserved. The phases, crystal structures, morphologies, and growth behavior of both the precursory and resultant products are characterized by powder X-ray diffraction (XRD), electron microscopy,scanning electron (SEM) and transmission electron (TEM) microscopy, and selected area electron diffraction (SAED). Detailed investigation of the formation mechanism of the porous Co3O4 nanobelts indicates topotactic nucleation and oriented growth of textured spinel Co3O4 nanowalls (nanoparticles) inside the nanobelts. Co3O4 nanocrystals prefer [0001] epitaxial growth direction of hexagonal , -Co(OH)2 nanobelts due to the structural matching of [0001] , -Co(OH)2//[111] Co3O4. The surface-areas and pore sizes of the spinel Co3O4 products can be tuned through heat treatment of , -Co(OH)2 precursors at different temperatures. The galvanostatic cycling measurement of the Co3O4 products indicates that their charge,discharge performance can be optimized. In the voltage range of 0.0,3.0,V versus Li+/Li at 40,mA g,1, reversible capacities of a sample consisting of mesoporous quasi-single-crystalline Co3O4 nanobelts can reach up to 1400,mA h g,1, much larger than the theoretical capacity of bulk Co3O4 (892,mA h g,1). [source] Genetics of the apnea hypopnea index in Caucasians and African Americans: I. Segregation analysisGENETIC EPIDEMIOLOGY, Issue 3 2002Sarah G. Buxbaum Abstract Differences in age of presentation and anatomic risk factors for obstructive sleep apnea (OSA) in Caucasians and African Americans suggest possible racial differences in the genetic underpinnings of the disorder. In this study, we assess transmission patterns in a Caucasian sample consisting of 177 families (N = 1,195) and in an African American sample consisting of 125 families (N = 720) for two variables: 1) apnea hypopnea index (AHI) log transformed and adjusted for age, and 2) AHI log transformed and adjusted for age and body mass index (BMI). We allowed for residual familial correlations and sex-specific means in all models. Analysis of the Caucasian sample showed transmission patterns consistent with that of a major gene that were stronger in the age-adjusted variable than in the age- and BMI-adjusted variable. However, in the African American families, adjusting for BMI in addition to age gave stronger evidence for segregation of a codominant gene with an allele frequency of 0.14, accounting for 35% of the total variance. These results provide support for an underlying genetic basis for OSA that in African Americans is independent of the contribution of BMI. Genet. Epidemiol. 22:243,253, 2002. © 2002 Wiley-Liss, Inc. [source] Association between unplanned readmission rate and volume of breast cancer operation casesINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 1 2006H-S Ahn Summary This study was conducted to investigate the relationship between unplanned readmission and breast cancer operation cases, with the assumption that the rate of unplanned readmission within 30 days of surgery was solely due to postsurgical complications. We divided hospitals into three categories based on breast cancer operation cases: low-volume hospitals (,50 annual procedures), medium-volume hospitals (51,99 annual procedures) and high-volume hospitals (,100 annual procedures). The medical records of 1351 subjects in 24 hospitals were investigated. We found unplanned readmission rates were significantly higher in hospitals with a lower surgical volume. From these three groups, a sample consisting of 1351 patients was created and 17 unplanned readmission cases (1.2%) were reported. Of these 17 cases, 12 (70.59%) cases were from low-volume hospitals. The present results indicate that unplanned readmission within 30 days following discharge is an important adverse outcome in breast cancer surgery. [source] A longitudinal study of the development of dieting among 7,17-year-old Swedish girlsINTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 1 2002Klara Halvarsson Abstract Objective To examine the extent to which the prevalence of self-reported dieting and the wish to be thinner changed in 7,15-year-old girls over a 3-year period, and to explore potential differences between cohorts recruited in 1995 and 1999. In addition, changes in eating attitudes (Children's Eating Attitudes Test [ChEAT]) were compared between 1995 and 1999. Method A three-wave longitudinal study including girls (n = 1,076,1,279) in five age groups (7, 9, 11, 13, 15, the Main Cohort) and an age-matched cross-sectional sample consisting of 1,759 girls (the Societal Cohort). Results A marked increase of the wish to be thinner was evident in the 10,14-year-old age range and significant increases in dieting attempts occurred mainly among 9,13-year-old girls. ChEAT scores were significantly higher among 11-year-olds in 1999 than in 1995. However, more 7-year-olds scored above the ChEAT cutoff (,15) in 1995 compared with 1999. Discussion There was an increasing trend in the wish to be thinner and in dieting attempts among 9,14-year-olds. Attitudes and behaviors associated with disturbed eating had increased between 1995 and 1999 only among the 11-year- olds. © 2002 John Wiley& Sons, Inc. Int J Eat Disord 31: 32,42, 2002. [source] Fall risk factors in older people with dementia or cognitive impairment: a systematic reviewJOURNAL OF ADVANCED NURSING, Issue 5 2009Jürgen Härlein Abstract Title.,Fall risk factors in older people with dementia or cognitive impairment: a systematic review. Aim., This paper is a report of a review conducted to identify and summarize specific risk factors for falls in older people with dementia or cognitive impairments as documented by prospective or case,control studies. Background., People with dementia have a doubled to threefold risk for falls, but the reasons for this have not yet been fully explained. Several integrative literature reviews discuss possible specific fall risk factors. However, there is lack of a systematic evaluation of studies. Data sources., The CINAHL, PubMed, EMBASE and PsychInfo databases were searched for the period between 1980 and May 2007. Review methods., A systematic review was conducted. Cohort or case,control studies published in English or German were included if they investigated risk factors for falls or fall-related injuries in a sample consisting of participants with dementia or cognitive impairment. Two reviewers independently assessed study quality. Results., Six prospective studies were included in the review. These differed concerning samples, settings, follow-up periods and examined variables. Therefore, meta-analysis was not possible. Eight categories of risk factors emerged: disease-specific motor impairments, impaired vision, type and severity of dementia, behavioural disturbances, functional impairments, fall history, neuroleptics and low bone mineral density. Conclusion., There is lack of sound studies examining fall risk factors in cognitively impaired elders. Well-known risk factors such as motor impairment show particular characteristics in people with dementia. In addition, behavioural disturbances contribute to their high risk for falls. Further prospective studies are needed. [source] Suggestive Linkage on Chromosome 1 for a Quantitative Alcohol-Related PhenotypeALCOHOLISM, Issue 10 2002Danielle M. Dick Background Alcohol dependence is a clinically and etiologically heterogeneous disorder. Accordingly, a variety of subtypes of alcohol-dependent individuals have been proposed, and multiple operational definitions of alcohol use, abuse, and dependence have been used in linkage analyses directed toward detecting genes involved in alcohol use and problems. Here, we develop quantitative phenotypes that characterize drinking patterns among both alcoholic and nonalcoholic subjects, and use these phenotypes in subsequent linkage analyses. Methods More than 9000 individuals from alcoholic and control families were administered a semistructured interview and personality questionnaire as part of the initial stage of the Collaborative Study on the Genetics of Alcoholism (COGA). A principal component analysis was conducted on items that captured many of the dimensions of drinking and related behaviors, including aspects of alcohol use, antisocial behavior and affective disturbance when drinking, and personality. Factor scores were computed for all individuals. Nonparametric linkage analyses were conducted on these factor scores, in the initial COGA sample consisting of 987 individuals from 105 extended families, and in a replication sample consisting of 1295 individuals from 157 extended families. Results Three factors were identified, accounting for 68% of the total variance. The most promising regions of linkage appeared for factor 2, on which higher scores indicate a later age of onset of regular drinking and higher harm avoidance. Chromosome 1 yielded consistent evidence of linkage in both samples, with a maximum lod score of 3.3 when the samples were combined for analysis. Consistent suggestion of linkage also was found to chromosome 15. Conclusions Developing novel phenotypes that more accurately model the effect of influential genes may help efforts to detect genes involved in complex disorders. Applying principal component analysis in the COGA sample provided support for some regions of linkage previously reported in COGA, and identified other new, promising regions of linkage. [source] A unified approach to regression analysis under double-sampling designsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES B (STATISTICAL METHODOLOGY), Issue 3 2000Yi-Hau Chen We propose a unified approach to the estimation of regression parameters under double-sampling designs, in which a primary sample consisting of data on the rough or proxy measures for the response and/or explanatory variables as well as a validation subsample consisting of data on the exact measurements are available. We assume that the validation sample is a simple random subsample from the primary sample. Our proposal utilizes a specific parametric model to extract the partial information contained in the primary sample. The resulting estimator is consistent even if such a model is misspecified, and it achieves higher asymptotic efficiency than the estimator based only on the validation data. Specific cases are discussed to illustrate the application of the estimator proposed. [source] Influence of depressed mood on neuropsychologic performance in HIV-seropositive drug usersPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2003Enrique Vázquez-Justo Abstract Some studies point out that depression affects the performance of HIV patients in neuropsychological tasks, but at present this effect is not clear. The purpose of the present paper was to study whether the presence of symptoms of depression affects the neuropsychologic performance of seropositive drug users in tasks of attention/concentration, learning and memory, language, construction and visuospatial function, speed of motor performance, cognitive flexibility, manual skill and concept formation and reasoning. In order to carry out this research a sample consisting of 127 male volunteer subjects was used. These subjects were distributed in four groups: one group consisted of HIV-seropositive drug users with symptoms of depression (n = 33); the second group consisted of HIV-seropositive drug users without symptoms of depression (n = 47); the third group was formed by HIV-seronegative drug users with symptoms of depression (n = 15) and the fourth group was formed by HIV-seronegative drug users without symptoms of depression (n = 32). The results reveal the effect of symptoms of depression (evaluated by the Beck Depression Inventory) on the neuropsychologic performance of seropositive drug users. This effect, however, was not observed in the seronegative group. These findings lead us to suggest that symptoms of depression constitute a risk factor for presenting neuropsychologic disturbances in seropositive subjects, which could well be acting as a factor that foments the neuropsychological effects of HIV. [source] A Life Table for Psittacosaurus lujiatunensis: Initial Insights Into Ornithischian Dinosaur Population BiologyTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 9 2009Gregory M. Erickson Abstract Very little is known about nonavian dinosaur population biology. Multi-individual sampling and longevity estimation using growth line counts can be used to construct life tables,the foundation for population analyses in ecology. Here we have determined the size and age distribution for a sample consisting of 80 individuals of the small ornithischian, Psittacosaurus lujiatunensis from the early Cretaceous Yixian Formation of China. Their ages ranged from less than a year to eleven years and the distribution was strongly right-skewed. This is consistent with taphonomic interpretations that these animals derive from a catastrophic death assemblage. The static life table analysis revealed the same general pattern of survivorship as tyrannosaurs including increased attrition before the attainment of full adult size. This may reflect increased physiological demands and/or predation exposure associated with reproduction. Collectively these findings suggest that most nonavian dinosaurs may have had a similar life history strategy. Anat Rec, 292:1514,1521, 2009. © 2009 Wiley-Liss, Inc. [source] Can Sanctions Reduce Insider Trading?ASIA-PACIFIC JOURNAL OF FINANCIAL STUDIES, Issue 4 2010The Experience of the USA in the 1980s G18; G34; G22 Abstract This paper empirically examines whether insider trading sanctions in the USA in the 1980s reduced insider trading in advance of mergers and acquisitions (M&A). Using a sample consisting of 291 firms, both merged and non-merged in 1983 and 1989, I measured insider trading volume and the "news media effect." I conclude that the sanctions reduced insider trading on average, and also resulted in larger noise trading on M&A-related news and rumors. No evidence was found that insiders were increasingly camouflaging their trades by concentrating them on days on that they knew trading volume would be abnormally high, such as on days containing M&A-related news. [source] The effects of defendant race, victim race, and juror gender on evidence processing in a murder trialBEHAVIORAL SCIENCES & THE LAW, Issue 2 2006Robert ForsterLee Ph.D. The effects of defendant race, victim race, and juror gender on sentencing and information processing were examined within the context of a murder trial. A sample consisting of 96, jury eligible White Australians read one of four versions of a real trial transcript, in which the race of a male defendant and female victim were varied. The participants imposed the severest sentences on the Indigenous (Black) defendant. Jurors were most lenient with White defendants who killed a White victim. Female jurors were more punitive than the males toward the Indigenous defendant. Jurors processed evidence systematically in same-race trials, but used both systematic and heuristic processing in mixed-race trials. In these instances, female jurors employed significantly more emotive responses, especially when the victim was Black. The effects of subtle racism and the black processing effect when the victim was non-White are considered. Copyright © 2006 John Wiley & Sons, Ltd. [source] The diagnostic utility of MOC31, BerEP4, RCC marker and CD10 in the classification of renal cell carcinoma and renal oncocytoma: an immunohistochemical analysis of 328 casesHISTOPATHOLOGY, Issue 5 2004C-C Pan Aims:, To demonstrate the diagnostic utility of MOC31, BerEP4, renal cell carcinoma marker (RCC Ma) and CD10 in the classification of RCC and renal oncocytoma, based upon a comprehensive immunohistochemical analysis. Methods and results:, Immunohistochemistry was performed on 328 samples consisting of 256 clear cell/conventional, 27 papillary, 28 chromophobe, five collecting duct, five unclassified RCCs and seven renal oncocytomas using antibodies MOC31, BerEP4 and antibodies against cytokeratins (KL-1, CAM5.2, 34,E12, cytokeratin 7), RCC Ma, epithelial membrane antigen, E-cadherin, CD10, CD15 and vimentin. Multivariate analysis showed that MOC31, BerEP4, RCC Ma and CD10 have discriminatory value. MOC31 and BerEP4 chiefly labelled distal tubules of normal kidney while RCC Ma and CD10 labelled the proximal tubules. Twenty-three chromophobe RCCs (82%) were reactive for MOC31, while only four clear cell RCCs and three papillary RCCs were positive for this marker. Clear cell RCCs were characterized by a high positive rate for CD10 (82%) and a low positive rate for BerEP4 (27%). Papillary RCCs frequently coexpressed RCC Ma and BerEP4 (51%). All renal oncocytomas were negative for MOC31 and CD10. Conclusions:, MOC31 has diagnostic merit in discerning chromophobe RCC. The CD10+/BerEP4, profile and RCC Ma+/BerEP4+ profile achieve moderate sensitivity and good specificity for clear cell RCC and papillary RCC, respectively. The non-reactivity for both MOC31 and CD10 is helpful in distinguishing renal oncocytoma from RCC. When properly selected, antibodies have immunohistochemical diagnostic utility for the classification of renal cortical epithelial tumours. [source] Chromosomal anomalies on 6p25 in iris hypoplasia and Axenfeld-Rieger syndrome patients defined on a purpose-built genomic microarray,HUMAN MUTATION, Issue 1 2004Rosemary Ekong Abstract In many inherited diseases, the same phenotype can be produced both by single-base changes and by large deletions, or in some cases by duplications. Routine high-throughput sequencing can now detect small mutations relatively easily in a diagnostic setting, but deletions and duplications in the 50,500-kb region remain a more difficult problem. We have explored the application of array-CGH to the detection of such changes on a set of 20 samples consisting of patients with eye diseases associated with changes on chromosome 6p25 together with unaffected individuals, as well as two samples from tuberous sclerosis 2 (TSC2)-affected patients. We developed a microarray consisting of degenerate oligonucleotide primer (DOP)-PCR products from 260 human genomic clones, including BACs, PACs, and cosmids. In a masked study, chromosome changes in patients with iris hypoplasia (duplication) and Axenfeld-Rieger syndrome (deletion) were unequivocally distinguished from controls. Of the 20 6p25 samples analyzed, 19 were analyzed correctly (10 duplication cases, two deletions, and seven normals), while one individual failed to give a result because of poor hybridization. The extent of the duplication or deletion estimated was similar to that obtained by independent and much more time-consuming FISH experiments. On the other hand, deletions in the two TSC2 -affected samples, previously mapped by DNA molecular combing, were not detected on the array, possibly due to the repeat content of that region. Excluding the 16p13 cosmids, consistent results were obtained from all other cosmid clones; the potential for producing affordable disease-specific diagnostic microarray as an adjunct to diagnosis is discussed. Hum Mutat 24:76,85, 2004. © 2004 Wiley-Liss, Inc. [source] Nestin expression in cutaneous melanomas and melanocytic neviJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2007Svetlana Brychtova Background:, Nestin is one of the intermediate filaments that are expressed in proliferating neural progenitor cells during development of the central nervous system (CNS) and peripheral nervous system. Postnatal re-expression of the protein occurs mainly under pathological conditions, including injury and neoplasia. In this study, nestin expression was detected in both benign and malignant melanocytic skin lesions and its diagnostic relevance was then evaluated. Methods:, Altogether 139 bioptic tissue samples consisting of 42 nodular melanomas, 32 superficial spreading melanomas, 12 metastatic melanomas, 10 dysplastic nevi and 43 common melanocytic intradermal and dermoepidermal nevi were analysed using indirect immunohistochemical staining. Results:, We demonstrated that nestin immunostaining was significantly increased in melanomas where it correlated with more advanced stages of the disease. Conclusion:, We conclude that expression of the intermediate filament protein nestin might be an indicator of tumor dedifferentiation and more aggressive behaviour. Furthermore, we suggest that nestin might be a relevant marker of tumorous and non-tumorous angiogenesis. [source] Muscle fiber properties and thermal stability of intramuscular connective tissue in porcine M. semimembranosusJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2009Liisa Voutila Abstract BACKGROUND: Strips can be easily peeled from raw destructured pork (M. semimembranosus, SM muscle) by hand but in normal meat these strips break. In general, destructured meat is pale in color. Porcine SM muscles have thick muscle fibers which could predispose them to destructuration. This study investigated whether the onset and peak temperatures of thermal shrinkage (To and Tp) of intramuscular connective tissue from SM muscles were associated with muscle fiber thickness, capillary density or extracellular space. We also investigated whether these muscle fiber properties of destructured muscles differed from those of normal muscles. RESULTS: The destructured and normal muscles were similar in muscle fiber cross-sectional area, capillary density, extracellular space and sarcomere length. To correlated negatively with sarcomere length. The water content of differential scanning calorimetry samples consisting of intramuscular connective tissue was higher in destructured muscles than in normal muscles. CONCLUSION: Muscle fiber properties (muscle fiber cross-sectional area and sarcomere length) and capillary density are similar in destructured and normal SM muscles. To and Tp of intramuscular connective tissue are similar in destructured and normal muscles. Muscle fiber properties show no association with the thermal shrinkage properties of intramuscular connective tissue. Copyright © 2009 Society of Chemical Industry [source] The antisite LuAl defect-related trap in Lu3Al5O12:Ce single crystalPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 14 2005M. Nikl Abstract Absorption, radioluminescence and thermoluminescence spectra were measured for a set of Lu3Al5O12:Ce samples consisting of a bulk single crystal and Liquid Phase Epitaxy-grown films prepared from the same raw materials. The triple peak structure within 120,200 K distinguished in thermolu- minescence glow curves of the bulk crystals was ascribed to an electron trap arising due to the LuAl antisite defect. The depth of the trap associated with the dominant peak at 142 K was evaluated using the initial rise method. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Age-related changes in semen quality characteristics and expectations of reproductive longevity in Duroc boarsANIMAL SCIENCE JOURNAL, Issue 4 2010Yu Hung HUANG ABSTRACT Quadratic fitting was used to regress semen characteristics of 1441 samples consisting of 12-month collection from 58 Duroc boars against animal age varied from 10 to 80 months. Data was divided into two groups of cool (14.0,22.7°C, RH 81.5%) and hot season (22.9,29.9°C, RH 86.6%), to test effects of age, season and their interactions. Results revealed that young boars of around 1 year old could endure the hot season. The endurance gradually diminished as animals grew. In the hot season animals exhibited peak performance at age around 33 month and it remained for 1 month, while cool-season kept boars could last for 48 months from 16 months old onward. The reproductive longevity should be 51 month in a subtropical environment and it may extend to 70 month if heat stress can be avoided. The estimated total sperm contribution of a Duroc boar would be 1.8 times more when kept below 22°C than in a natural subtropical environment. It is concluded that to maintain Duroc boars as semen donor to at least 4 years of age is feasible in a subtropical environment and boar longevity could reach 6 years old if well kept in a temperate region. [source] Sowing density and harvest time affect fibre content in hemp (Cannabis sativa) through their effects on stem weightANNALS OF APPLIED BIOLOGY, Issue 2 2009W. Westerhuis Abstract Sowing density and harvest time are considered important crop management factors influencing fibre quantity and quality in hemp (Cannabis sativa). We investigated whether the effects of these factors are essentially different or that both factors affect stem weight and thereby total and long-fibre content. The effects of all combinations of three sowing densities and three harvest times were studied for six different stem parts. Almost 500 samples consisting of stem parts from 50 plants and with a length of 50 cm were tested. Fibres were extracted by a controlled warm-water retting procedure, followed by breaking and scutching. The initial sample weight was fractionated into retting losses, wood, tow and long fibre. In both Italy and the Netherlands, crops were successfully established with different stem densities (99,283 m,2), plant heights (146,211 cm) and stem diameters (4.5,8.4 mm) at harvest. Stem dry matter yields (6.8,11.7 Mg ha,1) increased with a delay in harvest time but were not affected by sowing density. Retting loss percentages were lower in lower stem parts and decreased with later harvest because maturation was associated with increasing amounts of fibre and wood. Within a certain stem part, however, the absolute retting losses were constant with harvest time. Multiple linear regression analyses showed that the amount of fibre in a hemp stem is almost completely determined by the weight and the position of that stem part. When the plant grows, the increase in dry matter is split up into fibres and wood in a fixed way. This total fibre/wood ratio was highest in the middle part of the stem and lower towards both bottom and top. Sowing density and harvest time effects were indirect through stem weight. The long-fibre weight per stem increased with the total fibre weight and hence with stem weight. Stem weight increased with harvest time; as harvest time did not affect plant density, the highest long-fibre yields were obtained at the last harvest time. The long fibre/total fibre ratio was lowest in the bottom 5 cm of the stems but similar for all other parts. Sowing density and harvest time effects again were indirect. Fibre percentages in retted hemp decreased with increasing stem weights towards a level that is presumably a variety characteristic. The dry matter increase between harvests, however, is much more important with respect to total and long-fibre yield. [source] WT1 Is Not a Reliable Marker to Distinguish Reactive from Neoplastic Astrocyte Populations in the Central Nervous SystemBRAIN PATHOLOGY, Issue 6 2010T. David Bourne MD Abstract A diagnostic difficulty in neuropathology practice is distinguishing reactive from neoplastic astrocyte populations. This is particularly true in small biopsy samples that lack evidence of increased cellularity or mitotic activity, microvascular proliferation, or necrosis. We performed the current study to validate the previously reported finding that in the central nervous system, the expression of WT1 is limited to neoplastic astrocytes. We retrospectively studied WT1 protein expression by immunohistochemistry (IHC) in 100 formalin-fixed, paraffin-embedded brain tissue samples consisting of 3 normal control tissues, 44 cases of reactive gliosis, 49 gliomas and 4 lesions suspicious for glioma. In normal human cortex, WT1 staining was restricted to vascular endothelium. Most cases of reactive gliosis (82%) showed at least focal WT1 positivity, and analysis of specimens with electrode monitoring lesions showed an inverse relationship between WT1 expression intensity and the number of days from electrode placement to tissue resection. All glioma samples (100%) and all cases suspicious for glioma (100%) showed at least focal WT1 positivity. Our results likely differ from those in the prior report because of differences in tissue fixation and IHC methodology. Thus, our findings indicate that WT1 expression alone is not a reliable feature to distinguish reactive from neoplastic astrocytes. [source] | |||||||||||||||||||