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Selected AbstractsSimilar Deficiencies in Procedural Dermatology and Dermatopathology Fellow Evaluation despite Different Periods of ACGME Accreditation: Results of a National SurveyDERMATOLOGIC SURGERY, Issue 7 2008SCOTT R. FREEMAN MD BACKGROUND Fellow evaluation is required by the Accreditation Council for Graduate Medical Education (ACGME). Procedural dermatology fellowship accreditation by the ACGME began in 2003 while dermatopathology accreditation began in 1976. OBJECTIVE The objective was to compare fellow evaluation rigor between ACGME-accredited procedural dermatology and dermatopathology fellowships. METHODS Questionnaires were mailed to fellowship directors of the ACGME-accredited (2006,2007) procedural dermatology and dermatopathology fellowship programs. Information was collected regarding evaluation form development, delivery, and collection. RESULTS The response rates were 74% (25/34) and 53% (24/45) for procedural and dermatopathology fellowship programs, respectively. Sixteen percent (4/25) of procedural dermatology and 25% (6/24) of dermatopathology programs do not evaluate fellows. Fifty percent or less of program (4/8 procedural dermatology and 3/7 dermatopathology) evaluation forms address all six core competencies required by the ACGME. CONCLUSION Procedural fellowships are evaluating fellows as rigorously as the more established dermatopathology fellowships. Both show room for improvement because one in five programs reported not evaluating fellows and roughly half of the evaluation forms provided do not address the six ACGME core competencies. [source] Genetic disruption of CYP26B1 severely affects development of neural crest derived head structures, but does not compromise hindbrain patterningDEVELOPMENTAL DYNAMICS, Issue 3 2009Glenn Maclean Abstract Cyp26b1 encodes a cytochrome-P450 enzyme that catabolizes retinoic acid (RA), a vitamin A derived signaling molecule. We have examined Cyp26b1,/, mice and report that mutants exhibit numerous abnormalities in cranial neural crest cell derived tissues. At embryonic day (E) 18.5 Cyp26b1,/, animals exhibit a truncated mandible, abnormal tooth buds, reduced ossification of calvaria, and are missing structures of the maxilla and nasal process. Some of these abnormalities may be due to defects in formation of Meckel's cartilage, which is truncated with an unfused distal region at E14.5 in mutant animals. Despite the severe malformations, we did not detect any abnormalities in rhombomere segmentation, or in patterning and migration of anterior hindbrain derived neural crest cells. Abnormal migration of neural crest cells toward the posterior branchial arches was observed, which may underlie defects in larynx and hyoid development. These data suggest different periods of sensitivity of anterior and posterior hindbrain neural crest derivatives to elevated levels of RA in the absence of CYP26B1. Developmental Dynamics 238:732,745, 2009. © 2009 Wiley-Liss, Inc. [source] Reconstructing the past in medieval IcelandEARLY MEDIEVAL EUROPE, Issue 3 2006Chris Callow Locating and dating sagas is a difficult but still important task. This paper examines the relationship between the Sagas of Icelanders, which are concerned with tenth- and eleventh-century events, and the contemporary sagas of the mid-thirteenth century. Drawing upon models from anthropology, it looks at how contemporary ideas permeated these historicizing texts and how genealogy and geography act as structures around which the past is remembered. The many political relationships which occur in Laxdæla saga are analysed in relation to those from contemporary sagas from the same area of western Iceland. Since it appears that there is relatively little in common between the political situations depicted in Laxdæla saga and those portrayed in the contemporary sagas, it is likely that Laxdæla saga and the contemporary sagas were actually written down in different periods. It is possible, therefore, that the Sagas of Icelanders give us a view of the past which originates earlier than is usually suggested. [source] Soil erosion assessment using geomorphological remote sensing techniques: an example from southern ItalyEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2010Sergio Lo Curzio Abstract The aim of this study is to assess of the distribution and map the geomorphological effects of soil erosion at the basin scale identifying newly-formed erosional landsurfaces (NeFELs), by means of an integration of Landsat ETM 7+ remotely sensed data and field-surveyed geomorphological data. The study was performed on a 228·6,km2 -wide area, located in southern Italy. The study area was first characterized from a lithological, pedological, land-use and morpho-topographic point of view and thematic maps were created. Then, the georeferenced Landsat ETM 7+ satellite imagery was processed using the RSI ENVI 4.0 software. The processing consisted of contrast stretching, principal component analysis (PCA), decorrelation stretching and RGB false colour compositing. A field survey was conducted to characterize the features detected on the imagery. Particular attention was given to the NeFELs, which were located using a global positioning system (GPS). We then delimited the Regions of Interest (ROI) on the Landsat ETM 7+ imagery, i.e. polygons representing the ,ground-truth', discriminating the NeFELs from the other features occurring in the imagery. A simple statistical analysis was conducted on the digital number (DN) values of the pixels enclosed in the ROI of the NeFELs, with the aim to determine the spectral response pattern of such landsurfaces. The NeFELs were then classified in the entire image using a maximum likelihood classification algorithm. The results of the classification process were checked in the field. Finally, a spatial analysis was performed by converting the detected landsurfaces into vectorial format and importing them into the ESRI ArcViewGIS 9.0 software. Application of these procedures, together with the results of the field survey, highlighted that some ,objects' in the classified imagery, even if displaying the same spectral response of NeFELs, were not landsurfaces subject to intense soil erosion, thus confirming the strategic importance of the field-checking for the automatically produced data. During the production of the map of the NeFELs, which is the final result of the study, these ,objects' were eliminated by means of simple, geomorphologically-coherent intersection procedures in a geographic information system (GIS) environment. The overall surface of the NeFELs had an area of 22·9,km2, which was 10% of the total. The spatial analysis showed that the highest frequency of the NeFELs occurred on both south-facing and southwest-facing slopes, cut on clayey-marly deposits, on which fine-textured and carbonate-rich Inceptisols were present and displaying slope angle values ranging from 12° to 20°. The comparison of two satellite imageries of different periods highlighted that the NeFELs were most clearly evident immediately after summer tillage operations and not so evident before them, suggesting that these practices could have played an important role in inducing the erosional processes. Copyright © 2009 John Wiley & Sons, Ltd. [source] Tafoni development in a cryotic environment: an example from Northern Victoria Land, AntarcticaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2008Andrea Strini Abstract Tafoni are a type of cavernous weathering widespread around the world. Despite the extensive distribution of the tafoni, their genesis is not clear and is still a matter of debate, also because they occur in such different climatic conditions and on so many different types of substrate. Geomorphological characterization of more than 60 tafoni in three different Antarctic sites (two coastal and one inland) between 74 and 76° S with sampling of weathering products and salt occurrences are described together with thermal data (on different surfaces) and wind speed recorded in different periods of the year in a selected tafone close to the Italian Antarctic station. The aim of this present study is to provide further information to help understand the processes involved in the growth of tafoni in a cryotic environment, and the relationship of these processes to climate, with particular attention to the thermal regime and the role of wind. The new data presented in this paper suggest that there is no single key factor that drives the tafoni development, although thermal stress seems the most efficient process, particularly if we consider the short-term fluctuations. The data also confirm that other thermal processes, such as freezing,thawing cycles and thermal shock, are not really effective for the development of tafoni in this area. The wind speed measured within the tafoni is half that recorded outside, thus favouring snow accumulation within the tafoni and therefore promoting salt crystallization. On the other hand, the wind effect on the thermal regime within the tafoni seems negligible. While both salt weathering and thermal stress appear active in this cryotic environment, these are azonal processes and are therefore active in other climatic areas where tafoni are widespread (such as the Mediterranean region). Copyright © 2007 John Wiley & Sons, Ltd. [source] An experimental investigation of water level effects on the dynamic behaviour of a large arch damEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 8 2001Jean Proulx Abstract The need for full-scale dynamic tests, which are recognized as the most reliable method to evaluate a structure's vibration properties, is increasing as new analysis techniques are developed that take into account the complex interaction phenomenons that occur in dam,reservoir,foundation systems. They are extremely useful to obtain reliable data for the calibration of newly developed numerical methods. The Earthquake Engineering and Structural Dynamics Research Center (CRGP) at the University of Sherbrooke has been developing and applying dynamic testing methods for large structures in the past 10 years. This paper presents the experimental evaluation of the effects of the varying water level on the dynamic response of the 180 m Emosson arch dam in Switzerland. Repeated forced-vibration tests were carried out on the dam during four different periods of the reservoir's filling cycle during a one-year span. Acceleration and hydrodynamic pressure frequency responses were obtained at several locations while the dam was subjected to horizontal harmonic loading. The variation of the resonant frequencies as a function of the reservoir level is investigated. A summary of the ongoing numerical correlation phase with a three-dimensional finite element model for the dam,reservoir,foundation system is also presented. Copyright © 2001 John Wiley & Sons, Ltd. [source] Tricuspid Regurgitation after Orthotopic Heart TransplantationECHOCARDIOGRAPHY, Issue 1 2010Nishant Kalra M.D. Background: Tricuspid regurgitation (TR) is a relatively common abnormality in normal adults as well as after orthotopic heart transplantation (OHT). A few studies have shown reduction in the incidence of TR after OHT by total bicaval surgical anastomosis technique. Other studies reported no significant difference in the rates of TR between the standard and bicaval techniques. Objective: Evaluate and compare the degree of TR after OHT by standard and bicaval anastomosis techniques. Method: Echocardiograms from the first 56 consecutive patients that had the total bicaval surgical technique performed were retrospectively reviewed and compared with the last 57 consecutive patients who had the standard biatrial technique performed. Patients with adequate two-dimensional and Doppler echocardiograms were included. Results: No statistical difference was observed for each grade of TR at both early and late time points. No significant difference was observed between the TR velocities of both biatrial and bicaval anastomosis patients at different periods. Conclusion: There appears to be no difference between the TR severity and TR velocity at early and late time points regardless of anastomotic technique. (Echocardiography 2010;27:1-4) [source] Age-dependent clutch size in a koinobiont parasitoidECOLOGICAL ENTOMOLOGY, Issue 1 2005Jelmer A. Elzinga Abstract., 1. The Lack clutch size theory predicts how many eggs a female should lay to maximise her fitness gain per clutch. However, for parasitoids that lay multiple clutches it can overestimate optimal clutch size because it does not take into account the future reproductive success of the parasitoid. 2. From egg-limitation and time-limitation models, it is theoretically expected that (i) clutch size decreases with age if host encounter rate is constant, and (ii) clutch size should increase with host deprivation and hence with age in host-deprived individuals. 3. Clutch sizes produced by ageing females of the koinobiont gregarious parasitoid Microplitis tristis Nees (Hymenoptera: Braconidae) that were provided daily with hosts, and of females ageing with different periods of host deprivation were measured. 4. Contrary to expectations, during the first 2 weeks, clutch size did not change with the age of the female parasitoid, neither with nor without increasing host-deprivation time. 5. After the age of 2 weeks, clutch size decreased for parasitoids that parasitised hosts daily. The decrease was accompanied by a strong decrease in available eggs. However, a similar decrease occurred in host-deprived parasitoids that did not experience egg depletion, suggesting that egg limitation was not the only factor causing the decrease in clutch size. 6. For koinobiont parasitoids like M. tristis that have low natural host encounter rates and short oviposition times, the costs of reproduction due to egg limitation, time limitation, or other factors are relatively small, if the natural lifespan is relatively short. 7. Koinobiont parasitoid species that in natural situations experience little variation in host density and host quality might not have strongly evolved the ability to adjust clutch size. [source] Dispersal between host populations in field conditions: navigation rules in the parasitoid Venturia canescensECOLOGICAL ENTOMOLOGY, Issue 3 2003E. Desouhant Abstract. 1. Dispersal is a life-history trait that can have great ecological and evolutionary consequences, however understanding of how insects disperse is limited. 2. Navigation rules of the solitary koinobiont parasitoid of the pyralid moth larvae Venturia canescens (Gravenhorst) were studied in conditions that it is likely to meet when dispersing between host populations and in the absence of cues related directly to the presence of hosts. 3. Mark,release,recapture experiments were conducted in a natural host-free habitat, and letting the animals disperse for different periods. 4. In the presence of vegetation, wasps seemed to disperse rapidly (1 h for an area of ,,1 ha) and capture rates were independent of both dispersal time and distance from the release point. 5. The navigation rules of V. canescens during dispersal between tree stands can be summarised as: move up- or down-wind, avoid or pass through open, sunny areas, and go for shady and dense vegetation. 6. The consequences of the navigation rules for host,parasitoid dynamics are discussed in relation to different spatial scales. [source] THE ECONOMICS OF ACHIEVING COMPETITIVE BALANCE IN THE AUSTRALIAN FOOTBALL LEAGUE, 1897,2004ECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 4 2004Ross Booth This paper summarises some key aspects of a theoretical and empirical analysis of whether various labour market devices and revenue-sharing rules used in the Victorian Football League/Australian Football League (VFL/AFL) since its inception in 1897 have increased competitive balance by reducing the inequality in the distribution of player talent between clubs. The history of labour market intervention and revenue sharing in the VFL/AFL is discussed, with six different periods between 1897 and 2004 identified for analysis. Fort and Quirk's (1995) model of US professional team sports leagues is used to analyse the effectiveness of the various devices that have been used in the VFL/AFL, but only after adapting the model to allow for VFL/AFL clubs being win maximisers (subject to a budget constraint) rather than profit maximisers. The various devices used by the VFL/AFL are assessed in terms of their likely impact on competitive balance, with some significantly different theoretical predictions than under profit maximisation. It is found that free agency results in a less equal distribution of player talent under win maximisation, whilst both gate sharing and increases in shared league-revenue tend to equalise playing strengths (which is not the case under profit maximisation). Moreover, the invariance principle, that the effect of a player draft will be undermined by the sale (and/or trade) of player talent, is found not necessarily to hold under win maximisation and can be reduced or eliminated with a team salary cap. Whether the trade of players and draft choices can undermine a player draft is also considered. The conclusion reached is that a player draft, a team salary cap, and revenue sharing is the combination most likely to succeed in achieving higher levels of competitive balance. The evidence of competitive balance in the VFL/AFL is consistent with these predictions. [source] Comparing retention in treatment and mortality in people after initial entry to methadone and buprenorphine treatmentADDICTION, Issue 7 2009James Bell ABSTRACT Aim To compare retention in treatment and mortality among people entering methadone and buprenorphine treatment for opioid dependence. Data sources The Pharmaceutical Drugs of Abuse System (PHDAS) database records start- and end-dates of all episodes of methadone and buprenorphine treatment in New South Wales, and the National Death Index (NDI) records all reported deaths. Methods Data linkage study. First entrants to treatment between June 2002 and June 2006 were identified from the PHDAS database. Retention in treatment was compared between methadone and buprenorphine. Names were linked to the NDI database, and ,good matches' were identified. Deaths were classified as occurring during induction, maintenance and either post-methadone or post-buprenorphine, depending on the latest episode of treatment prior to death. The numbers of inductions into treatment, of total person-years spent in each treatment, and person-years post-methadone or buprenorphine, were calculated. Risk of death in different periods, and different treatments, was analysed using Poisson regression. Results A total of 5992 people entered their first episode of treatment,3349 (56%) on buprenorphine, 2643 on methadone. Median retention was significantly longer in methadone (271 days) than buprenorphine (40 days). During induction, the risk of death was lower for buprenorphine (relative risk = 0.114, 95% confidence interval = 0.002,0.938, P = 0.02, Fisher's exact test). Risk of death was lowest during treatment, significantly higher in the first 12 months after leaving both methadone and buprenorphine. Beyond 12 months after leaving treatment, risk of death was non-significantly higher than during treatment. Conclusions Buprenorphine was safer during induction. Despite shorter retention in treatment, buprenorphine maintenance was not associated with higher risk of death. [source] Is There Conceptual Convergence in Entrepreneurship Research?ENTREPRENEURSHIP THEORY AND PRACTICE, Issue 3 2006A Co-Citation Analysis of Frontiers of Entrepreneurship Research Conceptual convergence is often seen as a holy grail in entrepreneurship research. Yet little empirical research has focused specifically on the extent and nature of this convergence. We address this issue by content-analyzing the networks of co-citation emerging from the 20,184 references listed in the 960 full-length articles published in the Frontiers of Entrepreneurship Research series between 1981 and 2004. Our results provide evidence for the varying levels of convergence that have characterized entrepreneurship research over the years, as well as the evolution of the conceptual themes that have attracted scholars' attention in different periods. In addition, we provide evidence that the field relies increasingly on its own literature, something that points toward the unique contribution that it makes to the management sciences. [source] Localization of processes involved in methanogenic degradation of rice straw in anoxic paddy soilENVIRONMENTAL MICROBIOLOGY, Issue 8 2001Kristin Glissmann In anoxic paddy soil, rice straw is decomposed to CH4 and CO2 by a complex microbial community consisting of hydrolytic, fermenting, syntrophic and methanogenic microorganisms. Here, we investigated which of these microbial groups colonized the rice straw and which were localized in the soil. After incubation of rice straw in anoxic soil slurries for different periods, the straw pieces were removed from the soil, and both slurry and straw were studied separately. Although the potential activities of polysaccharolytic enzymes were higher in the soil slurry than in the straw incubations, the actual release of reducing sugars was higher in the straw incubations. The concentrations of fermentation products, mainly acetate and propionate, increased steadily in the straw incubations, whereas only a little CH4 was formed. In the soil slurries, on the other hand, fermentation products were low, whereas CH4 production was more pronounced. The production of CH4 or of fermentation products in the separated straw and soil incubations accounted in sum for 54,82% of the CH4 formed when straw was not removed from the soil. Syntrophic propionate degradation to acetate, CO2 and H2 was thermodynamically more favourable in the soil than in the straw fraction. These results show that hydrolysis and primary fermentation reactions were mainly localized on the straw pieces, whereas the syntrophic and methanogenic reactions were mainly localized in the soil. The percentage of bacterial relative to total microbial 16S rRNA content was higher on the straw than in the soil, whereas it was the opposite for the archaeal 16S rRNA content. It appears that rice straw is mainly colonized by hydrolytic and fermenting bacteria that release their fermentation products into the soil pore water where they are further degraded to CH4. Hence, complete methanogenic degradation of straw in rice soil seems to involve compartmentalization. [source] Immediate and Delayed Benefits of Play Behaviour: New Evidence from Chimpanzees (Pan troglodytes)ETHOLOGY, Issue 12 2004E. Palagi Evidence for the anticipation of competition at feeding time has been previously documented in both Pan species. Chimpanzees seem to cope with competitive tendency through behavioural mechanisms of tension reduction, and grooming is certainly one of these. Social play and grooming are often matched because they bring animals into close physical contact for long periods, and they have an important role in social cohesion. Our goal was to investigate the occurrence of play behaviour during the pre-feeding period, before a basic maintenance activity is about to take place, in the chimpanzee colony housed in the ZooParc de Beauval (St Aignan sur Cher, France). The group was composed of 10 adults and nine immature individuals. By scan animal sampling (344 h of observation), we recorded play and grooming interactions in all age-class combinations during four different periods (pre-feeding, feeding, post-feeding, control). We found peak levels of grooming interactions among adults during the pre-feeding time. A peak frequency at the pre-feeding time was also found in social play between adults and unrelated immature subjects. This finding suggests that during high tension periods, grooming and play might share similar functions in conflict management. Like grooming, play might have an important role to limit aggression and increase tolerance around food (immediate benefits). Immature animals showed a higher frequency of play in the pre-feeding than in any other condition (feeding, post-feeding, and control). During high excitement periods social play probably represents a safe mechanism for immature subjects to test their personal abilities (self-assessment), the strength/weakness of playmates, and the degree of cooperation/competition with them (social-assessment). In the light of this new evidence, we can assert that play behaviour is far from being a purposeless activity, at least in the chimpanzee colony under study. [source] Abstention, alcohol use and risk of myocardial infarction in men and women taking account of social support and working conditions: the SHEEP case,control studyADDICTION, Issue 10 2003Anders Romelsjö ABSTRACT Aims, Very few studies indicating that low,moderate alcohol consumption protects from myocardial infarction (MI) controlled for social support and working conditions, which could confound the findings. Therefore, a first aim was to study the risk of non-fatal and total MI in relation to volume of alcohol consumption and measures of social support and working conditions. A second aim was to analyse the impact of the volume of earlier alcohol use in abstainers. Design, Data came from a case,control study, the Stockholm Heart Epidemiology Program (SHEEP), including first MI among Swedish citizens 45,70 years old. Setting, Stockholm County 1992,94. Participants, There were 1095 cases of MI in men and 471 in women (928 and 372 were non-fatal), and 2339 living controls from the general population. Measurement, Information about alcohol use at different periods in life and job strain, social anchorage and life control besides pre-existing health problems, smoking, physical activity, socio-economic status and marital status was obtained by a questionnaire from the cases and the controls. Findings, In multivariate logistic regression analyses, the relative risk for MI (especially non-fatal) was reduced among alcohol consumers. RR for non-fatal MI was 0.52 (95% confidence intervals 0.32, 0.85) in men with a consumption of 50,69.9 g 100% ethanol/day and 0.21 (95% confidence interval 0.06, 0.77) in women with a consumption of 30 g or more per day (reference category 0.1,5 g 100% ethanol/day). Men who were abstainers during the previous 1,10 years and with an earlier average consumption of 5,30 g 100% ethanol/day had a significantly lower relative risk compared to such abstainers with an earlier higher consumption. Earlier consumption among abstainers may also have an impact on gender differences in MI. Analyses showed positive interaction between abstention and low life-control in women, but only 4% of the female cases were due to this interaction. There were no other interactions between measures of alcohol use and social anchorage, life control and working situations. Conclusion, Alcohol use had a protective impact on MI, with little impact of job strain, social anchorage and life control, giving increased support for a protective impact of low-moderate alcohol use. The level of previous alcohol consumption among male 1,10-year-long abstainers influenced the risk of MI. [source] Solid-State Photodimerization of Guest Molecules in Inclusion CompoundsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 18 2006Irena Zouev Abstract Photochemical dimerization reactions of 1,3-diphenyl-1-propen-3-one (chalcone), 9-acetylanthracene, and 9-(methoxycarbonyl)anthracene as guest molecules in inclusion compounds with 1,1,6,6-tetraphenyl-2,4-hexadiyne-1,6-diol were studied. The irradiation of a single crystal containing chalcone was carried out in a single step and resulted in a single crystal containing the photodimer in full occupancy. In the case of the crystal containing 9-acetylanthracene, X-ray diffraction data were collected after irradiation for different periods of time. Only one of the two crystallographically independent pairs of 9-acetylanthracene underwent solid-state photodimerization at ca. 11,% conversion to the head-to-tail dimer. Photodimerization of the 9-(methoxycarbonyl)anthracene inclusion compound led, after irradiation for 2.5 h, to ca. 37,% conversion. It was found that the molecules that were arranged in stacks had undergone photodimerization in two different ways, so that on the average it looked as if all the guest molecules had polymerized. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Return migration of adult Atlantic salmon, Salmo salar, in relation to water diverted through a power stationFISHERIES MANAGEMENT & ECOLOGY, Issue 1 2003E. B. Thorstad Abstract ,The migration of Atlantic salmon, Salmo salar L., returning to the River Suldalslågen, Norway, was studied in relation to redirection of freshwater flow through a power station. The outlet of the power station is situated in the Hylsfjord, a fjord adjacent to the river mouth. Seventy-two salmon were tagged with acoustic transmitters, released in the outer part of the fjord system and automatically recorded when entering the Hylsfjord or the river. Data were collected during one period when the power station was running and two periods when the power station was closed. The release of water from the power station did not greatly attract the salmon during their return migration. Proportions of salmon entering the river or time from release to entering the river did not differ among salmon tagged in the different periods. The salmon were recorded in the Hylsfjord both when the power station was running and closed and there were no differences in number of times, number of days or hours recorded in the Hylsfjord among salmon tagged in the three periods. The only significant difference found among periods was duration of continuous stays in the inner part of the Hylsfjord. This may indicate a slight attraction to the freshwater release, but the difference seems small (1.8 vs. 0.7 h) compared with the time the fish stayed in the fjord system before entering the river (16,85 days). [source] Relative susceptibility of oaks to seven species of Phytophthora isolated from oak forest soilsFOREST PATHOLOGY, Issue 6 2008Y. Balci Summary Isolates of Phytophthora cambivora, P. cinnamomi, P. citricola, P. europaea, P. quercetorum and two unidentified species were tested for their pathogenicity to eastern US oak species by root and stem inoculations. Experiments were conducted during two different periods and included 1-, 2- and 20-year-old oaks grown under greenhouse and field conditions. Species of Phytophthora were pathogenic in varying degrees to the oak species tested. All species were pathogenic to fine and taproots of at least one oak species. The fine root damage caused by the species of Phytophthora ranged from 9 to 55% when compared to the controls. Roots were more susceptible during the fall inoculation period than the summer. With exception of Phytophthora sp1 and P. quercina -like, all species of Phytophthora were pathogenic to oak stems with P. cinnamomi and P. citricola being the most aggressive. Quercus montana and Q. rubra were the most susceptible oak species to stem inoculation. Lesion sizes were considerably larger when 20-year-old trees were inoculated. Generally, no significant differences in lesion sizes were detected in greenhouse tests when the summer and fall inoculation periods were compared. However, on 2-year-old field-grown seedlings, lesion sizes were considerably smaller or not significantly different from controls during the fall inoculation period, suggesting lower, late season temperatures may restrict lesion development. [source] Life-history strategies in freshwater macroinvertebratesFRESHWATER BIOLOGY, Issue 9 2008WILCO C. E. P. VERBERK Summary 1Explaining spatial and temporal differences in species assemblages is a central aim of ecology. It requires a sound understanding of the causal mechanisms underlying the relationship of species with their environment. A species trait is widely acknowledged to be the key that links pattern and process, although the enormous variety of traits hampers generalization about which combination of traits are adaptive in a particular environment. 2In three steps, we used species traits to match species and environment, and chose lentic freshwater ecosystems to illustrate our approach. We first identified key environmental factors and selected the species traits that enable the organism to deal with them. Secondly, we investigated how investments in these traits are related (e.g. through trade-offs). Thirdly, we outlined 13 life-history strategies, based on biological species traits, their interrelations known from life-history theory and their functional implications. 3Species traits and environmental conditions are connected through life-history strategies, with different strategies representing different solutions to particular ecological problems. In addition, strategies may present an integrated response to the environment as they are based on many different traits and their interrelationships. The presence and abundance of (species exhibiting) different life-history strategies in a location may therefore give direct information about how a particular environment is experienced by the species present. 4Life-history strategies can be used to (i) explain differences in species assemblages either between locations or in different periods; (ii) compare waterbodies separated by large geographical distances, which may comprise different regional species pools or span species distribution areas and (iii) reduce often very complex, biodiverse assemblages into a few meaningful, easily interpretable relationships. [source] Biogeochemical changes induced in uranium mining waste pile samples by uranyl nitrate treatments under anaerobic conditionsGEOBIOLOGY, Issue 3 2009A. GEISSLER Response of the subsurface soil bacterial community of a uranium mining waste pile to treatments with uranyl nitrate over different periods of time was studied under anaerobic conditions. The fate of the added U(VI) without supplementation with electron donors was investigated as well. By using 16S rRNA gene retrieval, we demonstrated that incubation with uranyl nitrate for 4 weeks resulted in a strong reduction in and even disappearance of some of the most predominant bacterial groups of the original sample. Instead, a strong proliferation of denitrifying and uranium-resistant populations of Rahnella spp. from Gammaproteobacteria and of Firmicutes occurred. After longer incubations for 14 weeks with uranyl nitrate, bacterial diversity increased and populations intrinsic to the untreated samples such as Bacteroidetes and Deltaproteobacteria propagated and replaced the above-mentioned uranium-resistant groups. This indicated that U(VI) was immobilized. Mössbauer spectroscopic analysis revealed an increased Fe(III) reduction by increasing the incubation time from four to 14 weeks. This result signified that Fe(III) was used as an electron acceptor by the bacterial community established at the later stages of the treatment. X-ray absorption spectroscopic analysis demonstrated that no detectable amounts of U(VI) were reduced to U(IV) in the time frames of the performed experiments. The reason for this observation is possibly due to the low level of electron donors in the studied oligotrophic environment. Time-resolved laser-induced fluorescence spectroscopic analysis demonstrated that most of the added U(VI) was bound by organic or inorganic phosphate phases both of biotic origin. [source] Impact of new prostheses on the oral health related quality of life of edentulous patientsGERODONTOLOGY, Issue 1 2005J. L. Veyrune Objective:, A study was conducted to evaluate the impact of the placement of complete dentures by using the Global Oral Health Assessment Index (GOHAI). Background:, Oral health quality of life indicators can be used to evaluate the effects of dental treatments. Material and methods:, The 26 participants were treated in a French University Clinic during 2002. They were randomly divided into two groups. Each group received new prostheses, but evaluation of the quality of life was made at different periods [baseline, denture placement (group 1), 6 and 12 weeks (group 2) after placement]. A questionnaire was used to collect information on patient's satisfaction with the previous and new prostheses. Nonparametric tests were used to test the relationships between patients' satisfaction or baseline data and GOHAI variations with time as well as to compare mean values of GOHAI within each group. Results:, At baseline, the impact of oral health problems was apparent; the mean GOHAI-Add score was 45.8 (10.2). Six weeks after placement of the new denture, there was no difference in GOHAI scores compared with the initial assessment. An improvement in GOHAI score was observed 12 weeks after the participants received their new dentures (p < 0.05). Change in GOHAI-Add scores was negatively correlated with the initial GOHAI-Add score. Patients who preferred the new prosthesis enjoyed a positive change in GOHAI scores (p < 0.001). There was a relationship between participants' satisfaction with the new dentures and change in GOHAI scores (p < 0.05). Conclusion:, The GOHAI can be used to evaluate needs for and effect of the making of new complete dentures. [source] Production and behavioural responses of high- and low-yielding dairy cows to different periods of access to grazing or to a maize silage and soyabean meal diet fed indoorsGRASS & FORAGE SCIENCE, Issue 4 2006O. Hernandez-Mendo Abstract The study examined whether high-yielding cows grazing pasture respond differently from low-yielding cows in milk production and feeding behaviour, to increasing the time made available for eating a maize silage and soyabean meal (TAMS) diet indoors and reducing the time available for grazing (TAG). Two experiments, each lasting 42 d, were carried out in spring (Experiment 1) and autumn (Experiment 2) using Holstein-Friesian cows at two different levels of milk yield (MYL). Milk production and feeding behaviour were examined for TAG + TAMS systems of 19 h, TAG plus 1 h TAMS (19 + 1), and 5 h TAG plus 15 h TAMS (5 + 15). There were two levels of concentrate (0 and 6 kg d,1), and in the spring experiment two sward heights (4,6 and 8,10 cm) were also studied. Milk yield, persistency of milk yield, liveweight change and estimated total DM intake were significantly higher on the 5 + 15 than on the 19 + 1 grazing system in Experiment 1 but not in Experiment 2. There were no significant interactions of TAG + TAMS treatment with MYL for any production or behavioural measurements except for maize silage feeding time, where high MYL cows spent a significantly greater time eating maize silage than low MYL cows on the 5 + 15 treatment but not on the 19 + 1 treatment. It can be concluded that high- and low-yielding cows respond similarly in milk production and feeding behaviour to different combinations of TAG and TAMS. In autumn, estimated daily intakes of herbage were lower on both grazing treatments relative to spring, resulting from lower rates of herbage intake with no compensatory increase in grazing time. In contrast, rates of intake of maize silage were higher in autumn especially on the 19 + 1 system. These results may imply a change of preference from herbage to maize silage between spring and autumn. [source] Subclinical Left Ventricular Dysfunction in Migraine AttacksHEADACHE, Issue 1 2006Manuel Vidalón MD Objective.,The aim of the present study was to evaluate cardiac performance of patients with migraine attacks during the overload produced by phenylephrine infusion. Background.,It is known that circulatory changes occur during migraine. However, the relationship between this finding and transient cardiac dysfunction is still unknown. Methods.,By means of two-dimensional direct M-mode echocardiography, we measured fractional shortening, ejection fraction, and mean velocity of circumferential fibers shortening in 18 patients with migraine and in 10 normal subjects as a control group. These measures were performed in two different periods: during attack-free intervals and during attacks. Pain intensity of typical migraine attack was evaluated on a 0 to 10 scale. Results.,Cardiac size and function were normal at rest in both groups. However, during migraine attacks, phenylephrine infusion provoked significant decrease in fractional shortening, EF, and mean velocity of circumferential fibers shortening, followed by concomitant increase of headache severity. On the other hand, during the attack-free interval and in the control group phenylephrine infusion did not show significant changes in cardiac function parameters. Conclusions.,Our data suggest that left ventricular dysfunction during the phenylephrine test could participate in the complex pathophysiological mechanism of migraine attacks. [source] Probiotic administration in patients with ileal pouch,anal anastomosis for ulcerative colitis is associated with expansion of mucosal regulatory cellsINFLAMMATORY BOWEL DISEASES, Issue 5 2008Annamaria Pronio MD Abstract Background: Probiotics have anti-inflammatory effects in patients with inflammatory bowel disease and appear to regulate mucosal immune response through reductions in proinflammatory cytokines. The probiotic VSL#3 prevents pouchitis if started within a week of ileostomy closure and maintains remission following antibacterial treatment in patients with refractory or recurrent pouchitis. However, the efficacy of probiotics and their effects on regulatory cells if started at a greater time after surgery in patients undergoing ileal pouch anal anastomosis (IPAA) for ulcerative colitis are unknown. Methods: We conducted an open-label study in which 31 patients at different periods from surgery without signs and symptoms of pouchitis were randomized to 2 sachets of VSL#3 once daily or no treatment for 12 months. Pouchitis disease activity index (PDAI) was evaluated at baseline and after 3, 6, and 12 months. The percentage of CD4+ T lymphocytes expressing CD25 and the inactive form of transforming growth factor-, [latency-associated peptide (LAP)] were evaluated at baseline and after 3 and 6 months in peripheral-blood mononuclear cells and mucosal biopsies. Variation in tissue interleukin-1, and Foxp3 mRNA expression was also evaluated. Results: During the study period, VSL#3-treated patients showed a significant reduction in PDAI score and a significant increase in the percentage of mucosal CD4+CD25high and CD4+ LAP-positive cells compared with baseline values. Tissue samples at different points showed a significant reduction in IL-1, mRNA expression, and a significant increase in Foxp3 mRNA expression. Conclusions: We conclude that VSL#3 administration in patients with IPAA modulates the PDAI and expands the number of mucosal regulatory T cells. (Inflamm Bowel Dis 2008) [source] Moisture adsorption by milk whey protein filmsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2002C. M. P. Yoshida Edible films, using whey protein as the structural matrix, were tested for water vapour diffusion properties. Whey protein films were prepared by dispersing 6.5% whey protein concentrate (WPC) in distilled water with pH kept at 7.0. Glycerol was the plasticizer agent. Film slabs (13.5 × 3.5 cm) were put in a chamber at 25 °C and 75% relative humidity, being held in vertical planes for different periods of time. The mass gain was determined throughout the experiment. We show that moisture adsorption by milk whey protein films is well described by a linear diffusion equation model. After an adsorption experiment was performed the solution of the diffusion equation was fitted to the data to determine the diffusion coefficient of the material. [source] Temporal Variations in Fine Sand Assemblages in the North Aegean Sea (Eastern Mediterranean)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 2 2004Evdokia Kourelea Abstract Two sites were selected in the North Aegean Sea for the study of shallow fine sand assemblages, which are poorly known in the Eastern Mediterranean. The biomonitoring of these sites can provide useful information on the impact of human activities on the macrofaunal and meiofaunal composition of these assemblages. In order to examine this impact, sampling took place in five different periods between 2000 and 2001. The qualitative and quantitative compositions of the communities at the two sites showed certain differences, mostly between the sites and the year of sampling rather than between sampling periods, which would be the expected outcome. The communities seem to be affected by a combination of the human activities with the particular hydrodynamics of the studied sites. [source] Use of nonparametric statistical tests in defining the number of periods to include in an intertemporal DEA analysisINTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH, Issue 3 2007Taraneh Sowlati Abstract In any type of intertemporal efficiency analyses either locally or globally, units in different periods are compared against each other, and therefore it is assumed that no frontier shift exists within the periods of study. This assumption extends in window analysis to each window. In almost all studies in the past, the number of periods included in an intertemporal data envelopment analysis or the width of a window in a window analysis is determined without validating this assumption analytically. This is a problem which has not been fully addressed in the literature. This paper presents a new approach using nonparametric statistical tests to examine a frontier shift and determine the number of periods to include in an intertemporal analysis. The case of sawmills in Vancouver, Canada is used to demonstrate how to apply this new approach. [source] Carry-over effects in a Pacific seabird: stable isotope evidence that pre-breeding diet quality influences reproductive successJOURNAL OF ANIMAL ECOLOGY, Issue 2 2009Marjorie C. Sorensen Summary 1Understanding the interactions between different periods of the annual cycle in migratory animals has been constrained by our inability to track individuals across seasons. In seabirds, virtually nothing is known about how diet quality during the non-breeding period, away from the breeding grounds, might influence subsequent reproductive success. 2We used stable nitrogen (,15N) and carbon (,13C) isotopes to evaluate the effects of non-breeding diet quality on the timing of breeding and egg size in a population of Cassin's auklets (Ptychoramphus aleuticus) breeding on Triangle Island, British Columbia. Adult feathers are grown during two different periods of the annual cycle, which allowed us to estimate diet quality from the previous fall (October,November) and pre-breeding (February,March) period. 3We found that the estimated proportion of energetically superior copepods (Neocalanus spp.) in the pre-breeding diet tended to be higher in females that bred earlier and laid larger eggs, whereas energetically poor juvenile rockfish (Sebastes spp.) were dominant in the pre-breeding diets of females that bred later and laid smaller eggs. We detected no effect of fall diet quality on breeding date or egg size, and no effect of pre-breeding diet quality on breeding date in males. 4Pre-breeding diet quality was not related to body condition measured 1,2 days after laying, which suggests that females may need to attain a threshold condition before they initiate breeding and successfully rear young. 5Our results suggest that changes in climatic conditions during the pre-breeding period may have severe consequences for reproductive success by influencing breeding date and egg size. Our work emphasizes the importance of determining how events are linked throughout the annual cycle for understanding the fitness and population dynamics of migratory animals. [source] Dietary amino acids fed in free form or as protein do differently affect amino acid absorption in a rat everted sac modelJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 5 2008J. A. Nolles Summary In the present study, the effect of free amino acid (FAA) diets on the intestinal absorption rate of methionine and leucine was studied ,ex vivo' with rats adapted for different periods of time to the diets, using the everted sac method. The adaptation period to the 21% FAA diet with an amino acid content based on casein was either, 0 (no adaptation, N-ADA), 5 (short-term adaptation, ST-ADA), or 26,33 days (long-term adaptation, LT-ADA). Within the ST-ADA and the LT-ADA groups, three different levels of methionine were included: 50%, 100% and 200% of the level normally present in casein. All diets were iso-nitrogenous and iso-caloric. After the adaptation period (0, 5, or 26,33 days), intestinal everted sacs were prepared. Methionine or leucine was added to the medium as transport substrate. The methionine absorption rate of the rats of the LT-ADA groups was higher than that of the N-ADA groups. Furthermore, adaptation to 200% dietary methionine levels caused a significantly slower leucine absorption compared to the 100%, and 50% group. Methionine absorption was similar in the 100% and 200% groups, but the absorption of methionine in the 50% group was enhanced in the distal part of the intestines. We concluded that in response diets with 21% FAAs as only amino acid source, amino acid absorption is decreased to avoid toxic effects of high levels of methionine in the circulation. [source] Successful gonadal development and maturation of tench (Tinca tinca L.) in small concrete pondsJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2003J. M. Carral Summary The experiments were performed in a tench farm from autumn until the spawning season (June,July). Tench broodstocks from natural habitats were maintained in 25 × 6 × 1 m concrete ponds and fed on commercial trout pellets. Females and males were separated and maintained under natural photoperiod and temperature conditions at densities around 2 kg m,2. Water flow throughout was supplied at the rate of 15 L s,1. When females showed external signs of advanced gonadal development, induction of spawning was made by luteinizing hormone releasing factor (LH-RH) synthetic analogue administration at three different periods of the reproductive season (June,July). A single intramuscular injection (20 ,g kg,1 body weight) was administered to 110 mature females selected from a total of 150. The females were stripped 42 h (22°C) after hormone administration. The mean rate of stripped females to the number injected was 77%. Mean relative egg weight in relation to the weight of the stripped females was 5.61%. More than 90% of the males provided semen without hormonal induction. Differences in egg production and external egg quality were observed at different times of the spawning period. It was proven that tench maintained in small concrete tanks and fed on artificial diets were able to reach gonadal maturation. [source] | ||||||||||||||||||||||||||||||||||||||||||||||