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Selected AbstractsEpidemiology of Heterobasidion abietinum and Viscum album on silver fir (Abies alba) stands of the PyreneesFOREST PATHOLOGY, Issue 1 2010J. Oliva Summary In the last two decades, stand decline and increased mortality has affected silver fir (Abies alba) forests in the Spanish Pyrenees. Simultaneously severe occurrences of the root rot fungus Heterobasidion annosum s.l. and of the mistletoe Viscum album have been reported. We aimed to improve the understanding of the epidemiology of both pathogens in our region. All H. annosum isolates found on silver fir were typed as H. abietinum. H. abietinum was more frequently observed where cuttings had targeted fir trees rather than other species. H. abietinum fruiting bodies were observed in the most recently cut stumps. V. album was more abundant on more dominant fir trees, and in southern aspect stands. The number of V. album colonies in the stand correlated (R2 = 0.40) with silver fir mortality. Stands with a high level of V. album infection tended to have a smaller percentage of basal area in species other than silver fir, and they tended to be located on more south-facing slopes. H. abietinum was widespread in silver fir forests of the Pyrenees. Our data suggest that, in the Pyrenees, the observed H. abietinum incidence may represent a combination of both primary and secondary spread of the pathogen. Favouring mixed forests should be tested as a potential control method for V. album. The correlation between silver fir mortality and V. album infection warrants further study, as the observed tree mortality could have occurred due to other factors than V. album, such as drought damage. [source] Efficacy of ProTaper Universal rotary retreatment system for gutta-percha removal from root canalsINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2008L.-S. Gu Abstract Aim, To evaluate the efficacy of the ProTaper Universal rotary retreatment system for gutta-percha (GP) removal from root canals. Methodology, Root canals of 60 extracted human maxillary anterior teeth were prepared and filled with laterally condensed GP and AH Plus sealer. Teeth were divided into three groups: group A , GP removal completed with the ProTaper Universal rotary retreatment system and with further canal repreparation accomplished with ProTaper Universal rotary instruments; group B , GP removal was completed using Gates Glidden drills and Hedström files with chloroform as a solvent, followed with further canal repreparation with ProTaper Universal rotary instruments; group C , the same as group B for GP removal with further canal preparation with stainless steel K-flex files (Kerr). The operating time was recorded. Teeth were rendered transparent for the evaluation of the area of remaining GP/sealer in bucco-lingual and mesial,distal directions. Statistical analysis was performed by using repeated measures analysis of variance and anova. Results, The ProTaper Universal technique (group A) resulted in a smaller percentage of canal area covered by residual GP/sealer than in groups B and C, with a significant difference between groups A and C (P < 0.05). Mean operating time for group A was 6.73 min, which was significantly shorter (P < 0.05) than group B (10.86 min) and group C (13.52 min). Conclusions, In this laboratory study all test techniques left GP/sealer remnants within the root canal. The ProTaper Universal rotary retreatment system proved to be an efficient method of removing GP and sealer from maxillary anterior teeth. [source] Auditor Opinion Shopping and the Audit Committee: An Analysis of Suspicious Auditor SwitchesINTERNATIONAL JOURNAL OF AUDITING, Issue 1 2001Deborah Archambeault This study examines whether audit committee effectiveness characteristics are related to suspicious auditor switching. Using the agency and audit committee literature, we hypothesize that audit committee existence, the proportion of independent directors, member experience in accounting, auditing, and finance, number of committee meetings, and number of committee members should be inversely related to suspicious auditor switching. A sample of 60 matched U.S. firms was evaluated along the hypothesized dimensions after controlling for company size, industry, stock exchange, financial health, and management stock ownership. Collectively, univariate and logistic regression results provide support for our predictions. The findings indicate that suspicious switchers: (1) are less likely to have an audit committee, (2) have a smaller percentage of independent directors on the audit committee, (3) have fewer members with experience in accounting, auditing, or finance, (4) hold fewer audit committee meetings, and (5) have smaller audit committees than nonsuspicious switching companies. Exploratory analyses also reveal that audit committees for companies with suspicious switches had younger members, and fewer members with no stock ownership in the company served. [source] Fibre type composition of the human psoas major muscle with regard to the level of its originJOURNAL OF ANATOMY, Issue 6 2009Juraj Arbanas Abstract The aim of our study was to explore the fibre type composition of the human psoas major muscle at different levels of its origin, from the first lumbar to the fourth lumbar vertebra, and to compare the muscle fibre size and distribution of different fibre types between levels with respect to its complex postural and dynamic function. Muscle samples were collected from 15 young males (younger than 35 years). Serial transverse sections (5 ,m) of the samples were cut by cryomicrotome. Type I, IIA and IIX muscle fibres were typed using myosin heavy chain identification. The serial sections were analysed using a light microscope with a magnitude of 100×. The differences between measurements were evaluated using a repeated-measures anova and Scheffé test for post-hoc analysis. Our study showed that the human psoas major muscle was composed of type I, IIA and IIX muscle fibres. It had a predominance of type IIA muscle fibres, whereas type I muscle fibres had the largest cross-sectional area. Type IIX muscle fibres were present as a far smaller percentage and had the smallest cross-sectional area. Moreover, the fibre type composition of the psoas major muscle was different between levels of its origin starting from the first lumbar to the fourth lumbar vertebra. We conclude that the fibre type composition of the psoas major muscle indicated its dynamic and postural functions, which supports the fact that it is the main flexor of the hip joint (dynamic function) and stabilizer of the lumbar spine, sacroiliac and hip joints (postural function). The cranial part of the psoas major muscle has a primarily postural role, whereas the caudal part of the muscle has a dynamic role. [source] Study of the Dehydroxylation,Rehydroxylation of PyrophylliteJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2010Jose L. Perez-Rodriguez Pyrophyllite is a raw material of significant interest due to its large number of applications. Most of these applications require a thermal transformation of pyrophyllite; this thermal transformation implies the release of structural OH groups and the formation of new phases. In this paper, we report on the dehydroxylation of pyrophyllite and the reversibility of the process. A value of 224±16 kJ/mol for the dehydroxylation of pyrophyllite was obtained. In addition, it was observed that the partially or totally dehydroxylated pyrophyllite suffered a partial reversible rehydroxylation when cooled to room temperature. This rehydroxylation was substantiated by thermogravimetric measurements, while infrared spectroscopic studies showed that, during the rehydroxylation, the intensity of the OH band at 3675 cm,1 increased as two new bands at 3690 and 3702 cm,1 appeared. This rehydroxylation process was heavily influenced by the particle size of the pyrophyllite. Thus, smaller particles (<1 ,m) showed a larger rehydroxylation percentage (about 12%), while the larger ones (20,40 ,m) showed a smaller percentage (about 1.6%). The extent of rehydroxylation also depended on the dehydroxylation temperature and reached a maximum value at 750°C. [source] Skeletal and Pigmentation Defects following Retinoic Acid Exposure in Larval Summer Flounder, Paralichthys dentatusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2007Gabriela M. Martinez Supplementation of larval diets with vitamin A (VA) is routinely and successfully used to stimulate pigmentation development in hatchery-reared flatfishes. However, excess dietary VA can lead to high levels of its metabolite retinoic acid (RA) and has been associated with the occurrence of skeletal deformities, presumably via RA toxicity. We reared summer flounder larvae, Paralichthys dentatus, in water containing 0- to 20-nM RA to assess its effects on postmetamorphic pigmentation and on skeletal development. RA exposure disrupted pigmentation development: treated tanks had a smaller percentage of normally pigmented fish than did controls, with increased numbers of both hypo- and hyperpigmented individuals. Exposure also affected the development of several skeletal features: RA treatment correlated with a significant increase in the severity of defects in jaws, fins, hypurals, and vertebrae compared with control groups. [source] Lawyers' Roles in Voluntary Associations: Declining Social Capital?LAW & SOCIAL INQUIRY, Issue 3 2001John P. Heinz The extent and nature of lawyers'participation in civic life probably has important effects on the character of the community's activity and its out-comes. Where and how lawyers participate in voluntary associations may influence the ability of those organizations to function within the larger structure of American institutions. This paper compares findings from two surveys of Chicago lawyers, the first conducted in 1975 and the second in 1994-95. Contrary to some expectations, the available evidence does not suggest that community activities of lawyers decreased. Moreover, lawyers'energies in 1995 appear to have been devoted more often to socially concerned organizations, those with a reformist agenda, than had been the case in 1975. The types of organizations with the greatest increase in activity were religious and civic associations. A smaller percentage of the respondents held leadership positions in 1995 than in 1975, but, because of a doubling in the number of lawyers, the best estimate is that the bar's absolute level of contribution to community leadership did not change greatly. In both 1975 and 1995, a hierarchy of social prestige appears to have influenced the pattern of lawyers'community activities. Lawyers who had higher incomes, were middle-aged, were Protestants, and who had attended elite law schools were more likely to be active or leaders in most kinds of organizations. In ethnic and fraternal organizations, however, the elites of the profession had relatively low rates of participation, while government lawyers, solo practitioners, and graduates of less prestigious law schools predominated. Status hierarchies within the broader community,as well as social differences in taste, preference, or "culture",clearly penetrate the bar. [source] Analysis of haemochromatosis gene mutations in a population from the Mediterranean BasinLIVER INTERNATIONAL, Issue 4 2001Salvatore Campo Abstract:Background/Aims: The C282Y mutation in the haemochromatosis gene (HFE) located on chromosome 6 has been identified as the main genetic basis of hereditary haemochromatosis (HH). Two more mutations of that gene, H63D and S65C, appear to be associated with milder forms of HH. A high allele frequency for C282Y and H63D mutations was reported in populations from North Europe, while incomplete information is available for individuals from the Mediterranean Basin where C282Y homozygotes comprise a smaller percentage of HH cases. In this study we investigated the allele frequency of HFE mutations and the association between HFE mutations and cases of HH in a population from the South of Italy (Sicily and Calabria). In addition, we evaluated a possible association between HFE mutations and either chronic liver disease or type II diabetes. Patients and Methods: Three hundred and twenty-seven individuals (654 chromosomes) were tested for C282Y, H63D and S65C mutations of the HFE gene by restriction fragment length polymorphism. Four had HH, 23 had hepatocellular carcinoma, 100 had chronic liver disease, 100 had type II diabetes, and 100 were healthy controls. Results: Both C282Y and S65C mutations were each detected in one of the 654 chromosomes analysed (allele frequency=0.15%), while H63D change was found in 122 chromosomes (allele frequency=18.6%) and was equally distributed in all the categories examined. One healthy individual had compound heterozygosity for C282Y and H63D mutations. The frequency of C282Y in this Southern Italian sample was the lowest yet reported for a population of European origin. None of the four HH patients was either homozygous or heterozygous for C282Y. Conclusions: In Mediterranean populations from Southern Italy the C282Y mutation occurs sporadically and HFE polymorphisms seem to have little diagnostic relevance. [source] Are there ethnic differences in sleep architecture?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2002Judi Profant The possibility of ethnic differences in sleep architecture was initially examined in conjunction with studies of sleep apnea (study 1). This possibility was then examined in another cohort of patients to determine whether the results might generalize (study 2). Polysomnography was obtained in both cohorts as part of larger protocols investigating sympathetic nervous system activity, blood pressure, and sleep. Sleep monitoring took place in an inpatient clinical research center of a university hospital. Study 1 focused on sleep apnea physiology and involved volunteers with sleep apnea who were otherwise healthy. Study 2 focused on differences in stress reactivity between American Black and White subjects and involved hypertensive and normotensive volunteers who were otherwise healthy. Analyses include 61 participants from study 1 and 35 participants from study 2. Ethnicity in both cohorts was determined by self-report. Participants in both studies were monitored during sleep with traditional polysomnography including electroencephalography (EEG), electromyography (EMG), electrooculography (EOG), and oximetry. In Study 1, Blacks had longer TST (P < 0.01), more REM sleep (P < 0.05), and less WASO (P < 0.05) than Whites. After controling for RDI, Blacks had longer TST and spent a smaller percentage of time in deep sleep (P < 0.05). In study 2, Blacks had longer TST and REM sleep, lower percent deep sleep, and lower percent deep sleep controling for RDI (P < 0.05). In two separate studies, Blacks had longer TST, more minutes of REM, and lower percentage deep sleep. These findings suggest possible ethnic differences in sleep architecture. Am. J. Hum. Biol. 14:321,326, 2002. © 2002 Wiley-Liss, Inc. [source] PTEN expression is down-regulated in liver tissues of rats with hepatic fibrosis induced by biliary stenosisAPMIS, Issue 9 2009LI SEN HAO The gene phosphatase and tensin homolog deleted on chromosome 10 (PTEN) codes for a tumor-suppressor phospholipid phosphatase. Deletion, mutation or abnormal expression of PTEN is commonly found in many kinds of malignant tumors. At the time of this study, though, the role of PTEN expression in the pathology of hepatic fibrosis remains unclear. In this study, we investigate the dynamic expression of PTEN in a rat model of hepatic fibrosis, with special emphasis on the activation and proliferation of hepatic stellate cells (HSC) in vivo. The rat model of hepatic fibrosis used in this study employed common bile duct ligation. At four time points, the expression of PTEN in hepatic tissues and activated HSC in rat liver tissues was measured by immunohistochemical staining, Western blotting, real-time fluorescent quantitative PCR and immunofluorescence confocal laser scanning microscopy, respectively. Further, ,-smooth muscle actin (,-SMA), an activated HSC marker in rat liver tissues, was detected by immunohistochemical staining. This study showed that aggravation of hepatic fibrosis led to gradually decreasing expression of PTEN in the hepatic tissues. Further, as hepatic fibrosis worsens, PTEN-expressing activated HSC accounts for an increasingly smaller percentage of all activated HSC. In contrast, the percentage of ,-SMA-expressing HSC cells increases significantly. In conclusion, expression of PTEN mRNA and protein is down-regulated in fibrogenic rat liver tissue, and its expression in HSC in vivo also decreases with progression of fibrosis. Thus, these results show that the dynamic expression of PTEN in hepatic tissues negatively correlates with activation and proliferation of HSC. [source] Rare Species and the Use of Indicator Groups for Conservation PlanningCONSERVATION BIOLOGY, Issue 3 2003Joshua J. Lawler Although tests of the concept have produced varied results, sites selected to address indicator groups can include a high proportion of other species. We tested the hypothesis that species at risk of extinction are not likely to be included in sites selected to protect indicator groups. Using a reserve-selection approach, we compared the ability of seven indicator groups,freshwater fish, birds, mammals, freshwater mussels, reptiles, amphibians, and at-risk species of those six taxa,to provide protection for other species in general and at-risk species in particular in the Middle Atlantic region of the United States. Although sites selected with single taxonomic indicator groups provided protection for between 61% and 82% of all other species, no taxonomic group provided protection for more than 58% of all other at-risk species. The failure to cover at-risk species is likely linked to their rarity. By examining the relationship between a species' probability of coverage by each indicator group and the extent of its geographic range within the study area, we found that species with more restricted ranges were less likely to be protected than more widespread species. Furthermore, we found that although sites selected with indicator groups composed primarily of terrestrial species ( birds and mammals ) included relatively high percentages of those species ( 82,85% ) they included smaller percentages of strictly aquatic species (27,55%). Finally, of both importance and possible utility, we found that at-risk species themselves performed well as an indicator group, covering an average of 84% of all other species. Resumen: Los indicadores de la biodiversidad han sido propuestos como una herramienta potencial en la selección de áreas para conservación cuando la información sobre la distribución de algunas especies es escasa. A pesar de que algunas evaluaciones de este concepto han producido resultados variados, los sitios seleccionados para evaluar grupos indicadores pueden incluir una alta proporción de otras especies. Evaluamos la hipótesis de que las especies en riesgo de extinción probablemente no se incluyan en sitios seleccionados para proteger grupos indicadores. Usando la metodología de selección de reserva, comparamos la capacidad de siete grupos indicadores ( peces de agua dulce, aves, mamíferos, almejas de agua dulce, reptiles, anfibios y especies en riesgo de estos seis taxones ) para proveer protección a otras especies en general y especies en riesgo, en particular, en la región del Atlántico Medio de los Estados Unidos. A pesar de que los sitios con un solo grupo indicador proporcionaron protección para el 61% al 82% de todas las otras especies, ningún grupo taxonómico proporcionó protección para más del 58% de todas las otras especies en riesgo. La incapacidad de proteger especies en riesgo posiblemente se vincule con su rareza. Al examinar la relación entre la probabilidad de cobertura de una especie para cada grupo indicador y la extensión de su rango geográfico dentro del área de estudio, encontramos que las especies con rangos más restringidos tenían menor probabilidad de ser protegidas que las especies de distribución más amplia. Además, encontramos que, a pesar de que los sitios seleccionados con grupos indicadores compuestos principalmente por especies terrestres ( aves y mamíferos ) incluyeron porcentajes relativamente altos de estas especies ( 82%,85% ), éstos incluyeron porcentajes más bajos de especies estrictamente acuáticas ( 27%,55% ). Finalmente, de importancia y posible utilidad, encontramos que las especies en riesgo, por si mismas, funcionaron bien como grupo indicador, abarcando, en promedio, el 84% de todas las otras especies. [source] Differentials in Adult Mortality and Activity Limitation by Years of Education in the United States at the End of the 1990sPOPULATION AND DEVELOPMENT REVIEW, Issue 4 2004Michael T. Molla This study examines mortality differentials and health disparities between educational groups within the 1998 adult population (ages 25 and older) in the United States. Mortality differentials are measured using average life expectancy and health disparities by expected years without activity limitation. The results indicate that for both sexes, higher education is associated with higher life expectancy. Those with higher levels of education also have higher life expectancy without activity limitation. Adults with higher education can also expect to enjoy a greater percentage of their expected lives free of any form of activity limitation. At each level of education, adult females have a higher level of activity limitation compared to adult males. At the same level of education, adult females expect to enjoy smaller percentages of their remaining lives free of activity limitation compared to adult males of the same age. [source] Evolutionary significance of fecundity reduction in threespine stickleback infected by the diphyllobothriidean cestode Schistocephalus solidusBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010DAVID C. HEINS Parasites may cause fecundity reduction in their hosts via life-history strategies involving simple nutrient theft or manipulation of host energy allocation. Simple theft of nutrients incidentally reduces host energy allocation to reproduction, whereas manipulation is a parasite-driven diversion of energy away from host reproduction. We aimed to determine whether the diphyllobothriidean cestode parasite Schistocephalus solidus causes loss of fecundity in the threespine stickleback fish (Gasterosteus aculeatus) through simple nutrient theft or the manipulation of host energy allocation. In one stickleback population (Walby Lake, Matanuska-Susitna Valley, Alaska), there was no difference in the sizes and ages of infected and uninfected reproducing females. Lightly- and heavily-infected females produced clutches of eggs, but increasingly smaller percentages of infected females produced clutches as the parasite-to-host biomass ratio (PI) increased. Infected, clutch-bearing sticklebacks showed reductions in clutch size, egg mass, and clutch mass, which were related to increases in PI and reflected a reduction in reproductive parameters as growth in parasite mass occurs. The findings obtained for this population are consistent with the hypothesis of simple nutrient theft; however, populations of S. solidus in other regions may manipulate host energy allocation. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 835,846. [source] | |||||||||||||