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Selected AbstractsTemporal Extrapolation of PVA Results in Relation to the IUCN Red List Criterion ECONSERVATION BIOLOGY, Issue 1 2003Oskar Kindvall For a population viability analysis ( PVA) to be useful for assessing a species' threat category, the results must have been expressed as the full extinction probability function over time or at least for the three specified time frames. Often this is not the case, and extrapolations from different kinds of PVA results ( e.g., mean time to extinction ) are often necessary. By means of analytic models, we investigated the possibilities of extrapolation. Based on our results, we suggest that extrapolation is not advisable due to the huge errors that can occur. The extinction probability function is the best kind of summary statistic to use when applying criterion E, but even then the threat categorization may be ambiguous. If the extinction risk is low in the near future but increases rapidly later on, a species may be classified as vulnerable even though it is expected to become extinct within 100 years. To avoid this, we suggest that the guidelines to the IUCN Red List criteria include three reference lines that allow for interpretation of the PVA results in the context of the three threat categories within the entire period of 100 years. If the estimated extinction probability function overshoots one of these functions, the species should be classified accordingly. Resumen: Las categorías de amenaza de la lista roja de la IUCN ( críticamente en peligro, en peligro y vulnerable ) están definidos por un juego de criterios ( A-E ). El criterio E se define cuantitativamente por tres límites especificados de riesgo de extinción ( 50%, 20% y 10% ), cada uno de los cuales se asocia a un marco temporal determinado. Para poder usar el análisis de viabilidad poblacional ( PVA ) durante la evaluación de la categoría de amenaza de una especie, los resultados deben ser expresados en función de probabilidad de extinción total sobre un tiempo o al menos para los tres marcos temporales especificados. Frecuentemente este no es el caso y las extrapolaciones de diferente tipo de resultados de PVA ( tiempo promedio de extinción ) son usualmente necesarias. Por medio de modelos analíticos investigamos las posibilidades de extrapolación. En base a nuestros resultados sugerimos que la extrapolación no es recomendable debido a una enorme cantidad de errores que pueden ocurrir. La función de probabilidad de extinción es el mejor tipo de resumen estadístico a usar cuando se aplica el criterio E, pero, aún así, la categorización de amenaza puede ser ambigua. Si el riesgo de extinción es bajo en un futuro inmediato pero incrementa muy rápidamente después, una especie puede ser clasificada como vulnerable aunque se espere que se extinga dentro de los próximos 100 años. Para evitar esto, sugerimos que los lineamientos de los criterios de la Lista Roja de la UICN incluyan tres lineas de referencia que permitan la interpretación de los resultados del PVA en el contexto de las tres categorías dentro de un periodo completo de 100 años. Si la función de probabilidad de extinción estimada se extiende más allá de una de estas funciones, las especies deberán ser clasificadas según sea el caso. [source] Methods for the analysis of trends in streamflow response due to changes in catchment conditionENVIRONMETRICS, Issue 7 2001R. A. Letcher Abstract Two algorithms for analysing changes in streamflow response due to changes in land use and farm dam development, based on the Estimated Generalized Least Squares (EGLS) and the Generalized Additive Model (GAM) methods, were compared on three catchments in the Macquarie River Basin in NSW, Australia. In order to account for the influence of climatic conditions on streamflow response, the IHACRES conceptual rainfall-runoff model was calibrated on a daily time step over two-year periods then simulated over the entire period of concurrent rainfall, streamflow and temperature data. Residuals or differences between observed and simulated flows were calculated. The EGLS method was applied to a smoothing of the residual (daily) time series. Such residuals represent the difference between the simulated streamflow response to a fixed catchment condition (in the calibration period) and that due to the actual varying conditions throughout the record period. The GAM method was applied to quarterly aggregated residuals. The methods provided similar qualitative results for trends in residual streamflow response in each catchment for models with a good fitting performance on the calibration period in terms of a number of statistics, i.e. the coefficient of efficiency R2, bias and average relative parameter error (ARPE). It was found that the fit of the IHACRES model to the calibration period is critically important in determining trend values and significance. Models with well identified parameters and less correlation between rainfall and model residuals are likely to give the best results for trend analysis. Copyright © 2001 John Wiley & Sons, Ltd. [source] Application of a constant blood withdrawal method in equine exercise physiology studiesEQUINE VETERINARY JOURNAL, Issue 6 2001P. BARAGLI Summary The aim of the present study was to test a constant blood withdrawal method (CBWM) to collect blood samples from horses during treadmill exercise. CBWM was performed in 4 Standardbreds and 5 Haflinger horses. A peristaltic pump was used to control blood aspiration from an i.v. catheter via an extension line. Blood was collected using an automatic fractions collector, with a constant delay time between the drawing of blood and sample collection. Blood withdrawal using CBWM was made during a treadmill standardised exercise test (SET). A blood flow of 12 ml/min was used and samples collected every 60 s during the entire period of exercise. The volume of blood collected in each sample tube was 12.1 ± 0.2 ml, with a delay time of mean ± s.d. 25.3 ± 0.8 s. Plasma lactate kinetics based on measurement of lactate in each fraction showed an exponential increase during the first 13 min of exercise (10.5 min of SET and 2.5 min recovery). The peak plasma lactate concentration was observed between 2.5 and 5.5 min after the end of SET. CBWM permits the kinetics of lactate and other blood-borne variables to be studied over time. This method could be a valuable aid for use in studying equine exercise physiology. [source] Shaky attachments: Individual-level stability and change of partisanship among West German voters, 1984,2001EUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 4 2006RÜDIGER SCHMITT-BECK In this article, the authors take advantage of a unique longitudinal database , the German Socio-Economic Panel (GSOEP) , to test the basic premise of partisanship's high persistence. Analysing individual-level data from 18 annual panel waves conducted in West Germany between 1984 and 2001, it was found that only a minority of the electorate appears steadfast with regard to partisanship over the entire period. Using event history analysis, the authors demonstrate how movements from partisanship into independence and changes between parties are affected by: personal attributes of voters, especially cognitive mobilisation; by properties of their social contexts, in particular spousal relationships and family constellations; by situational contexts, specifically election campaigns; and by the type of party with which voters identify. [source] Going Public: An Empirical Investigation of U.S. Bound Israeli IPOsFINANCIAL MARKETS, INSTITUTIONS & INSTRUMENTS, Issue 3 2010Iftekhar Hasan Between 1985,2003, more than 120 Israeli companies went public in the U.S., bringing the accumulated number of U.S. bound, Israeli initial public offerings (IPOs) to a figure greater than all other foreign countries combined. In this study, we compare the short and long run performance of Israeli IPOs to that of similar international and U.S. IPOs. Holding all else equal, we find that Israeli IPOs are significantly less underpriced than their local and foreign counterparts. As we examine the characteristics of Israeli issuers, we find that they differ than those of other foreign and local issuers in some important dimensions that compensate investors for information asymmetry and risk. First, compared to their home market capitalization size, U.S. bound Israeli IPOs, are significantly larger than the IPOs conducted by their foreign counterparts. Second, Israeli issuers tend to perform better than other foreign and U.S. local IPOs during our entire period of observation. Third, to a large extent, the Israeli firms in our sample have products, licensing or franchising relationships or venture capital funds with strong roots in the U.S. prior to the IPO. And fourth, the relevant investor community of Israeli IPOs, at least at the early stages, is small and overwhelmingly American. Our findings are consistent with prior studies documenting that firms raising capital outside of their domicile country are typically a select group of high quality firms in need of external financing that cannot be sufficiently provided in their home market. [source] Role of land cover changes for atmospheric CO2 increase and climate change during the last 150 yearsGLOBAL CHANGE BIOLOGY, Issue 8 2004Victor Brovkin Abstract We assess the role of changing natural (volcanic, aerosol, insolation) and anthropogenic (CO2 emissions, land cover) forcings on the global climate system over the last 150 years using an earth system model of intermediate complexity, CLIMBER-2. We apply several datasets of historical land-use reconstructions: the cropland dataset by Ramankutty & Foley (1999) (R&F), the HYDE land cover dataset of Klein Goldewijk (2001), and the land-use emissions data from Houghton & Hackler (2002). Comparison between the simulated and observed temporal evolution of atmospheric CO2 and ,13CO2 are used to evaluate these datasets. To check model uncertainty, CLIMBER-2 was coupled to the more complex Lund,Potsdam,Jena (LPJ) dynamic global vegetation model. In simulation with R&F dataset, biogeophysical mechanisms due to land cover changes tend to decrease global air temperature by 0.26°C, while biogeochemical mechanisms act to warm the climate by 0.18°C. The net effect on climate is negligible on a global scale, but pronounced over the land in the temperate and high northern latitudes where a cooling due to an increase in land surface albedo offsets the warming due to land-use CO2 emissions. Land cover changes led to estimated increases in atmospheric CO2 of between 22 and 43 ppmv. Over the entire period 1800,2000, simulated ,13CO2 with HYDE compares most favourably with ice core during 1850,1950 and Cape Grim data, indicating preference of earlier land clearance in HYDE over R&F. In relative terms, land cover forcing corresponds to 25,49% of the observed growth in atmospheric CO2. This contribution declined from 36,60% during 1850,1960 to 4,35% during 1960,2000. CLIMBER-2-LPJ simulates the land cover contribution to atmospheric CO2 growth to decrease from 68% during 1900,1960 to 12% in the 1980s. Overall, our simulations show a decline in the relative role of land cover changes for atmospheric CO2 increase during the last 150 years. [source] An evaluation of sediment rating curves for estimating suspended sediment concentrations for subsequent flux calculations,HYDROLOGICAL PROCESSES, Issue 17 2003Arthur J. Horowitz Abstract In the absence of actual suspended sediment concentration (SSC) measurements, hydrologists have used sediment rating (sediment transport) curves to estimate (predict) SSCs for subsequent flux calculations. Various evaluations of the sediment rating-curve method were made using data from long-term, daily sediment-measuring sites within large (>1 000 000 km2), medium (<1 000 000 to >1000 km2), and small (<1000 km2) river basins in the USA and Europe relative to the estimation of suspended sediment fluxes. The evaluations address such issues as the accuracy of flux estimations for various levels of temporal resolution as well as the impact of sampling frequency on the magnitude of flux estimation errors. The sediment rating-curve method tends to underpredict high, and overpredict low SSCs. As such, the range of errors associated with concomitant flux estimates for relatively short time-frames (e.g. daily, weekly) are likely to be substantially larger than those associated with longer time-frames (e.g. quarterly, annually) because the over- and underpredictions do not have sufficient time to balance each other. Hence, when error limits must be kept under ±20%, temporal resolution probably should be limited to quarterly or greater. The evaluations indicate that over periods of 20 or more years, errors of <1% can be achieved using a single sediment rating curve based on data spanning the entire period. However, somewhat better estimates for the entire period, and markedly better annual estimates within the period, can be obtained if individual annual sediment rating curves are used instead. Relatively accurate (errors <±20%) annual suspended sediment fluxes can be obtained from hydrologically based monthly measurements/samples. For 5-year periods or longer, similar results can be obtained from measurements/samples collected once every 2 months. In either case, hydrologically based sampling, as opposed to calendar-based sampling is likely to limit the magnitude of flux estimation errors. Published in 2003 John Wiley & Sons, Ltd. [source] Variability of extreme temperature events in south,central Europe during the 20th century and its relationship with large-scale circulationINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2003Peter Domonkos Abstract The variability of winter extreme low-temperature events and summer extreme high-temperature events was investigated using daily temperature series (1901,98) from 11 sites in central and southern Europe. An extreme temperature event (EXTE) is defined by various threshold values of daily temperature or daily temperature anomaly. Systematic changes in the frequencies of EXTEs are investigated by the Mann,Kendall test and a method based on the Wilcoxon test. The catalogue of macrocirculation types over central Europe (the Hess,Brezowsky classification) is applied to investigate the connections between EXTEs and large-scale circulation. Circulation classes (HBC) are defined, and mostly spatial averages of EXTEs are examined. There were large long-term fluctuations in the frequencies of both winter extreme cold events (EXCEs) and summer extreme warm events (EXWEs) during the 20th century. The systematic changes referring to the entire period indicate a slight warming tendency, but only a few of the changes, mostly in the northernmost sites, are statistically significant. Strong connections are present between the frequencies of EXTEs and the large-scale circulation on various time scales, particularly for EXCEs. The spatial differences of EXTE fluctuations and EXTE,HBC connections are small within the study area. Northerlies and easterlies, as well as meridional and anticyclonic situations, are favourable for EXCEs, whereas southerlies and persistent anticyclonic situations are favourable for EXWE occurrences. In the latest decades, a decline in the frequency of EXCEs and a sharp increase in the frequency of EXWEs happened, and the residence times of the circulation patterns over central Europe became longer both in winter and summer. Copyright © 2003 Royal Meteorological Society [source] Effects of sequential exposure to lipopolysaccharide and heat stress on dental pulp cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2006Chiaki Kitamura Abstract In the present study, we examined the effects of sequential exposure to bacterial lipopolysaccharide (LPS) and heat stress on dental pulp cells. LPS induced the proliferation of pulp cells through the activation of p38 MAPK. HSP27 was expressed in cells with or without LPS during the entire period of heat stress, while transiently phosphorylated by short-term heat stress. In LPS-treated cells, short-term heat stress also induced the phosphorylation of HSF1. The immediate phosphorylation of HSF1 and HSP27 in LPS-treated cells by short-term heat stress occurred dependent on the activation of p38 MAPK. However, with long-term heat stress, the activation of HSF1 and induction of HSP27 occurred independent of p38 MAPK. Further, full activation of Akt in LPS-treated cells was immediately induced by short-term heat stress and lasted during the entire period of heat stress. I,B, was induced and phosphorylated throughout sequential exposure to LPS and heat stress. These results suggest that LPS has the unique effects on the cytoprotection and the cell death of pulp cells during heat stress through the modification and the activation of heat stress responsive molecules, HSF1 and HSP27, and cell survival molecules, Akt and NF-,B/I,B,. J. Cell. Biochem. 99: 797,806, 2006. © 2006 Wiley-Liss, Inc. [source] Evaluation of the Personal Dental Services (Wave 1) for Lambeth, Southwark and Lewisham Primary Care Trusts , Part 1: Retrospective analyses of registration data and access issuesJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 3 2005Helen Best BDS MDS PhD Abstract Aim/objective, The purpose of the study was to undertake analyses of registration data for the personal dental services (PDS) of Lambeth, Southwark and Lewisham primary care trusts and relate the analyses to the PDS goal ,of ,increasing ,uptake ,of ,dental services. Method, Secondary analyses of registration statistics provided by the Dental Practice Board were undertaken for both 1 years pre-PDS (October 1997 to September 1998) and post-PDS (October 1998 to March 2003) periods. Three sets of analyses were undertaken to consider different aspects of changing registrations: (1) Absolute numbers of patients registered at each time interval; (2) Rates of change in numbers of patients registered for the entire period after the introduction of PDS; and (3) Rates of change in numbers of patients registered ,for ,the ,most recent 3 years of available data. Results, There was a significant increase in the numbers of children registered under capitation, post-PDS as compared to the pre-PDS level (all ages and both genders combined). Post-PDS, the rate of increase for the children was approximately one additional child per practice per month (0.96, 95% CI 0.41,1.52). Similarly there was a significant trend for increasing adults registrations over time of about two and a half adults per practice per month (2.42, 95% CI 0.90,3.95). There was no evidence of a change in registrations for children or adults in total over the most recent period of 3 years. Conclusions, The analysis of the absolute numbers of registered patients each month indicated that the PDS practices had more children registered than before the implementation of the PDS scheme, but not adults. Overall post-implementation there was a trend for increasing registrations in both children and adults, but the most recent data indicated a plateau effect. Further consideration of facilitators to achieve PDS goals of improved uptake of services is required, particularly as they relate to local contexts. [source] Anti-inflammatory effects of continuous passive motion on meniscal fibrocartilageJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2005Mario Ferretti Abstract Motion-based therapies have been applied to promote healing of arthritic joints. The goal of the current study was to determine the early molecular events that are responsible for the beneficial actions of motion-based therapies on meniscal fibrocartilage. Rabbit knees with Antigen-Induced-Arthritis (AIA) were exposed to continuous passive motion (CPM) for 24 or 48 h and compared to immobilized knees. The menisci were harvested and glycosaminoglycans (GAG), interleukin-1, (IL-1,), matrix metalloproteinase-1 (MMP-1), cyclooxygenase-2 (COX-2), and interleukin-10 (IL-10) were determined by histochemical analysis. Within 24 h, immobilized knees exhibited marked GAG degradation. The expression of proinflammatory mediators MMP-1, COX-2, and IL-1, was notably increased within 24 h and continued to increase during the next 24 h in immobilized knees. Knees subjected to CPM revealed a rapid and sustained decrease in GAG degradation and the expression of all proinflammatory mediators during the entire period of CPM treatment. More importantly, CPM induced synthesis of the anti-inflammatory cytokine IL-10. The results demonstrate that mechanical signals generated by CPM exert potent anti-inflammatory signals on meniscal fibrochondrocytes. Furthermore, these studies explain the molecular basis of the beneficial effects of CPM observed on articular cartilage and suggest that CPM suppresses the inflammatory process of arthritis more efficiently than immobilization. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Differences in Evaporation Between a Floating Pan and Class A Pan on Land,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 3 2008Jason R. Masoner Abstract:, Research was conducted to develop a method for obtaining floating pan evaporation rates in a small (less than 10,000 m2) wetland, lagoon, or pond. Floating pan and land pan evaporation data were collected from March 1 to August 31, 2005, at a small natural wetland located in the alluvium of the Canadian River near Norman, Oklahoma, at the U.S. Geological Survey Norman Landfill Toxic Substances Hydrology Research Site. Floating pan evaporation rates were compared with evaporation rates from a nearby standard Class A evaporation pan on land. Floating pan evaporation rates were significantly less than land pan evaporation rates for the entire period and on a monthly basis. Results indicated that the use of a floating evaporation pan in a small free-water surface better simulates actual physical conditions on the water surface that control evaporation. Floating pan to land pan ratios were 0.82 for March, 0.87 for April, 0.85 for May, 0.85 for June, 0.79 for July, and 0.69 for August. [source] Effect of food shortage and temperature on oxygen consumption in the lesser mealworm, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae)PHYSIOLOGICAL ENTOMOLOGY, Issue 4 2003D. Renault Abstract., Temperature and food availability are limiting factors for the establishment of tropical insects in temperate countries. In the alien pest beetle, Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae), starvation and temperature have a significant impact on metabolic rate with oxygen consumption ranging from 0.5 µmol/g fresh mass (FM)/h at 12 °C to 3.4 µmol/g FM/h at 24 °C. At 12 °C, oxygen consumption decreased continuously during an entire period of starvation. However, at 16, 20 and 24 °C, beetles display a marked hyperactivity that leads to an increase in the oxygen consumption level during the first week of starvation, followed by a steep decrease until the end of the starvation period. Oxygen consumption either does not decline in fed beetles (observed at higher temperatures) or declines at a much shallower rate than in starved beetles (observed at cooler temperatures). During the first week of refeeding, Oxygen consumption rose steeply at 16, 20 and 24 °C before levelling off to the initial value (t0). At 12 °C, no compensation process was observed during recovery. This study reveals that an important threshold in the biology of A. diaperinus lies between 12 and 16 °C, leading to the onset of reduced locomotor activity and the promotion of survival to the detriment of reproduction. This ,sit and wait' behaviour is proposed as an adaptive strategy (i.e. inactivity and lower oxygen consumption coupled with low energetic requirements and high recovery abilities). Such behaviour and the observed hyperactivity were rarely described in insects before the present study. Together, the previous and present results suggest that A. diaperinus populations are likely maintained in temperate regions by immigration from warmer situations. [source] Resveratrol attenuates 1,2-dimethylhydrazine (DMH) induced glycoconjugate abnormalities during various stages of colon carcinogenesisPHYTOTHERAPY RESEARCH, Issue 8 2009Murugan Sengottuvelan Abstract Although a myriad of health promoting effects has been attributed to resveratrol (Res) (3,5,4,-trihydroxy- trans -stilbene), a phytoalexin, the most interesting is its anticancer property. The aim of this work was to elucidate the effectiveness of Res against cellular transformation (glycoconjugate alterations) initiated by 1,2-dimethylhydrazine (DMH), a colon specific carcinogen. Group 1 were control rats, group 2 were control rats that received Res (8 mg/kg body weight orally every day), rats in groups 3,6 were treated weekly with DMH (20 mg/kg body weight, subcutaneously × 15 times). In addition, groups 4,6 received Res (as in group 2) in three dietary regimens: initiation (I), post-initiation (PI) and entire period (EP). At the end of the 30 week experimental period in DMH alone exposed rats, altered levels of glycoconjugates (total hexoses, fucose, hexosamine and sialic acid) were observed in liver, intestine and colon tissues. Of the three dietary regimens of Res, the entire period supplementation significantly (p < 0.01) modulated the levels of glycoconjugates and reduced the incidence of adenoma and adenocarcinoma. These findings suggest that Res may extend its chemopreventive effect by restoring the alteration in glycoconjugates that are thought to be involved in the colonic malignant transformation process in this experimental model. Copyright © 2009 John Wiley & Sons, Ltd. [source] Fexofenadine, an H1-receptor antagonist, partially but rapidly inhibits the itch of contact dermatitis induced by diphenylcyclopropenone in patients with alopecia areataTHE JOURNAL OF DERMATOLOGY, Issue 2 2006Kazumoto KATAGIRI ABSTRACT Antihistamines have been used for the treatment of not only allergic diseases such as allergic urticaria and rhinitis, but also of eczematous skin diseases because of their anti-pruritic effects. Moreover, the pruritus associated with eczematous diseases is considered to be induced, in part, by histamine. However, it is unclear whether antihistamines inhibit the itch of eczematous diseases in the absence of topical corticosteroids. In this study, we investigated the anti-pruritic effect of the antihistamine, fexofenadine, on the itch of contact dermatitis that was induced by topical application of diphenylcyclopropenone for the treatment for alopecia areata. Thirteen patients with alopecia areata, who had been treated weekly with topical immunotherapy with diphenylcyclopropenone for 3 months to 2 years, recorded the severity of their itching on a visual analog scale before and 3, 6, 12, 24, 48 and 72 h after application of diphenylcyclopropenone for 4 consecutive weeks. Seven patients took fexofenadine during the first and third weeks, and six patients took fexofenadine during the second and fourth weeks. The severity of itching reached a maximum 6,12 h after the induction of the contact dermatitis in most of the patients. However, fexofenadine partially but rapidly reduced the severity of itching for 72 h during the entire period of treatment in the absence of topical corticosteroids. Our results suggest that fexofenadine can be beneficial in the daily management of patients with itching due to eczematous disease. [source] The Really Long-Run Performance of Initial Public Offerings: The Pre-Nasdaq EvidenceTHE JOURNAL OF FINANCE, Issue 4 2003Paul A. Gompers Financial economists have intensely debated the performance of IPOs using data after the formation of Nasdaq. This paper sheds light on this controversy by undertaking a large, out-of-sample study: We examine the performance for five years after listing of 3,661 U.S. IPOs from 1935 to 1972. The sample displays some underperformance when event-time buy-and-hold abnormal returns are used. The underperformance disappears, however, when cumulative abnormal returns are utilized. A calendar-time analysis shows that over the entire period, IPOs return as much as the market. The intercepts in CAPM and Fama,French regressions are insignificantly different from zero, suggesting no abnormal performance. [source] Conservative Management of Vestibular Schwannomas: An Effective Strategy,THE LARYNGOSCOPE, Issue 6 2008Gian Gaetano Ferri MD Abstract Objectives: Stimulated by the availability of a larger sample of patients and a longer follow-up period, we update our experience with conservative management of vestibular schwannomas. Study Design: Patients with intracanalicular and small/medium-sized tumors have been followed prospectively at a tertiary referral center. Methods: One hundred twenty-three patients affected by sporadic vestibular schwannoma were primarily observed by means of magnetic resonance imaging scans. In case of significant tumor growth (,2 mm), patients were either surgically treated or submitted to radiotherapy, but, not rarely, they continued to follow the "wait-and-scan" policy. Tumor-size changes over time were also evaluated with hearing function. Statistical analysis with predictive growth factors was performed. Results: Almost two thirds (64.5%) of the cases did not show tumor growth during the entire period of observation (mean follow-up period, 4.8 yrs). Among growing tumors, 16 patients were surgically treated with no complications or facial nerve palsy. Less than half (45.5%) of the patients presented useful hearing (classes A and B of the American Academy of Otolaryngology,Head and Neck Surgery classification) at diagnosis, and 41 (73.2%) patients had preserved hearing during follow-up independently from the tumor growth rate. Conclusions: Conservative management of vestibular schwannoma appears to be a safe procedure because most tumors do not grow and surgical outcomes are not affected by possible delays. In the great majority of cases, useful hearing is maintained over time. Because of the irregular behavior of the tumor, periodic neuroradiologic scans are mandatory to limit late surgical risks. [source] Changes of the Swedish Bordetella pertussis population in incidence peaks during an acellular pertussis vaccine period between 1997 and 2004,APMIS, Issue 4 2007ABDOLREZA ADVANI In a surveillance programme undertaken from 1997 through 2004, Bordetella pertussis isolates and clinical information were collected after introduction of acellular pertussis vaccines (Pa) in 1996. Changes in the B. pertussis population were studied in three incidence peaks: 1999,2000, 2002 and 2004. Available isolates from 158 fully vaccinated children representing all of Sweden, plus 37 from the Gothenburg area 2003,2004, were analysed by pulsed-field gel electrophoresis (PFGE), serotyping and sequencing of the virulence factor genes pertussis toxin subunits 1 and 3 (ptxA, ptxC), pertactin (prn), tracheal colonisation factor (tcfA) and fimbria3 (fim3). Allele ptxA1 was found in all isolates. There was a statistically significant increasing trend in three out of five studied genes, ptxC, prn and tcfA, and for a fourth, Fim3, if Gothenburg strains were included. The PFGE profile BpSR11 appearing in the 1999,2000 peak dominated by ,23% during the entire period, bringing with it the allele combination 1/2/2/2/B (ptxA1/ptxC2/prn2/tcfA2/fim3B). Other BpSR11-related profiles with the same allele combination and more than 82% similarity,BpSR5 in the 2002 peak and BpSR12 in the 2004 peak,appeared with an increasing trend. Although vaccination with Pa has reduced disease, new variants have emerged representing clones surviving in the immunized population. [source] Factors affecting the occupation of a colony site in Sydney., New South Wales by the Grey-headed Flying-fox Pteropus poliocephalus (Pteropodidae)AUSTRAL ECOLOGY, Issue 1 2001K. A. PARRY-JONES Abstract Previous authors have reported that Pteropus poliocephalus colony sites are occupied in response to blossom availability. However, in the present study it is reported that at the Gordon site in suburban Sydney, colony numbers were negatively correlated with the occurrence of pollen in the droppings. In addition, in contrast to reported occupational patterns at other colony sites, where flying-foxes are not present at the site during winter and early spring, the Gordon site was occupied by substantial numbers of flying-foxes throughout the entire period of 62 months from 1985 to 1990. As a result of the introduction of plants native to other parts of Australia and exotics from other continents, there is a variety of foods available throughout the year in the Sydney region, in comparison with less urbanized areas. This food supply permits the occupation of the Gordon colony site during winter and spring and reduces the migratory behaviour of flying-foxes throughout the year. It is concluded that in the absence of a restrictive food supply, the occupational pattern of the Gordon colony of P. poliocephalus is the result of the reproductive requirements of the species modified by the vagaries of blossom production in the native forests outside the foraging range of the colony. [source] Factors affecting the occupation of a colony site in Sydney, New South Wales by the Grey-headed Flying-fox Pteropus poliocephalus (Pteropodidae)AUSTRAL ECOLOGY, Issue 1 2001K. A. Parry-Jones Abstract Previous authors have reported that Pteropus poliocephalus colony sites are occupied in response to blossom availability. However, in the present study it is reported that at the Gordon site in suburban Sydney, colony numbers were negatively correlated with the occurrence of pollen in the droppings. In addition, in contrast to reported occupational patterns at other colony sites, where flying-foxes are not present at the site during winter and early spring, the Gordon site was occupied by substantial numbers of flying-foxes throughout the entire period of 62 months from 1985 to 1990. As a result of the introduction of plants native to other parts of Australia and exotics from other continents, there is a variety of foods available throughout the year in the Sydney region, in comparison with less urbanized areas. This food supply permits the occupation of the Gordon colony site during winter and spring and reduces the migratory behaviour of flying-foxes throughout the year. It is concluded that in the absence of a restrictive food supply, the occupational pattern of the Gordon colony of P. poliocephalus is the result of the reproductive requirements of the species modified by the vagaries of blossom production in the native forests outside the foraging range of the colony. [source] Lack of adverse effects in pregnant/lactating female rats and their offspring following pre- and postnatal exposure to ELF magnetic fieldsBIOELECTROMAGNETICS, Issue 4 2004Moon-Koo Chung Abstract We have recently reported that exposure of pregnant rats to 60 Hz at field strengths up to 0.5 mT during the entire period of pregnancy did not induce any biologically significant effects on both pregnant dams and embryo-fetal development. The present study was carried out to investigate the potential effects of gestational and lactational MF exposure on pregnancy, delivery, and lactation of dams and growth, behavior, and mating performance of their offspring in rats. Timed-pregnant female Sprague,Dawley (SD) rats (24/group) received continuous exposure to 60 Hz magnetic field (MF) at field strengths of 0 (sham control), 5 ,T, 83.3 ,T, or 0.5 mT. Dams received MF or sham exposures for 21 h/day from gestational day 6 through lactational day 21. Experimentally generated MF was monitored continuously throughout the study. No exposure-related changes in clinical signs, body weight, food consumption, pregnancy length, and necropsy findings were observed in dams. Parameters of growth, behavior, and reproductive performance of offspring showed no changes related to MF exposure. There were no adverse effects on embryo-fetal development of F2 offspring from dams exposed to MF. In conclusion, exposure of pregnant SD rats to 60 Hz at field strengths up to 0.5 mT from gestational day 6 to lactational day 21 did not produce biologically significant effects in dams, F1 offspring, or F2 fetuses. Bioelectromagnetics 25:236,244, 2004. © 2004 Wiley-Liss, Inc. [source] Reproductive biology of Boswellia serrata, the source of salai guggul, an important gum-resinBOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2005V. G. SUNNICHAN Detailed studies were carried out on the phenology, floral biology, pollination ecology and breeding system of Boswellia serrata Roxb. (Burseraceae) the source of ,salai guggul'. The trees remain leafless during the entire period of flowering and fruiting. The inflorescence is a terminal raceme and produces up to 90 bisexual, actinomorphic flowers. On average a flower produces 10 044 ± 1259 starch-filled pollen grains. About 85% of the fresh pollen grains are viable; the pollen to ovule ratio is 3348 : 1. The stigma is of the wet papillate type. The style is hollow with three flattened stylar canals filled with a secretion product. The stylar canals are bordered by a layer of glandular canal cells. The inner tangential wall of the canal cells shows cellulose thickenings. The ovary is trilocular and bears three ovules, one in each locule. Flowers offer nectar and pollen as rewards to floral visitors. The giant Asian honey bee (Apis dorsata) and A. cerana var. indica(Indian honey bee) are the effective pollinators. The species is self-incompatible and the selfed pollen tubes are inhibited soon after their entry into the stigma. Self-pollen tubes develop a characteristic ,isthmus' as a result of enlargement of the tube soon after emergence through the narrow germ pore. Cross-pollinated flowers allowed normal pollen germination and pollen tube growth, and resulted in fruit- and seed-set. Under open pollination fruit-set was only about 10%. Although manual cross-pollinations increased fruit set, it was only up to about 20%. Low fruit set appears to be the result of inadequate cross-pollination and other constraints, presumably limitation of available nutrients. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 147, 73,82. [source] The Pursuit of Magnetic Shadows: The Formal-Empirical Dipole Field of Early-Modern GeomagnetismCENTAURUS, Issue 3 2008Art. R. T. Jonkers ,observations of skylfull pylotts is the onlye waye to bring it in rule; for it passeth the reach of naturall philosophy. , Michael Gabriel, 1576 (Collinson, 1867, p. 30) Abstract The tension between empirical data and formal theory pervades the entire history of geomagnetism, from the Middle Ages up to the present day. This paper explores its early-modern history (1500,1800), using a hybrid approach: it applies a methodological framework used in modern geophysics to interpret early-modern developments, exploring to what extent formal conjectures shaped observation and vice versa. A range of pertinent case studies supports classification of this entire period as proto-scientific, characterised by the initial formation of theories being largely disconnected from observational constraints, and their subsequent evolution being advanced primarily by their empirical falsification, and not necessarily associated with the introduction of an alternative. The few exceptional instances of purely data-driven discovery were essentially due to an improved signal-to-noise ratio. [source] Long-term results of cataract surgery with implantation of a mechanically, reversibly adjustable intraocular lens: *Acri.Tec AR-1 PC/IOLACTA OPHTHALMOLOGICA, Issue 2008CE JAHN Purpose To investigate long-term safety and function of a mechanically, reversibly adjustable intraocular lens in human eyes Methods Clinical long-term monitoring of the initial 38 eyes of 38 patients with senile cataract after implantation of the *Acri.Tec AR-1 PC/IOL including a control group. Results Median follow-up was 25 (range 6 to 52 months). Throughout the entire period of observation all eyes were behaving clinically in the same way as if implanted with a conventionel PC/IOL. 2 eyes were adjusted surgically 2 weeks after implantation. 19/38 eyes underwent Nd:YAG laser capsulotomy after a median period of 12 (range 6 to 43) months after implantation. Median change of spherical equivalent between 1 month and the last visit was 0 (range , 0.5 to + 0.5) diopters. At the last visit median best visual acuity was 0.7 (range 0.2 to 1.0) for eyes with the *Acri.Tec AR-1 PC/IOL and 0.8( range 0.3 to 1.0) for the control group. Both eyes having undergone adjustment surgery had visual acuity of 0.8 rsp 1.0 with stable refractions 45 rsp. 42 months after adjustment surgery. Conclusion The *Acri.Tec AR-1 PC/IOL implanted into the capsular bag of adult human eyes is a safe PC/IOL. Refraction is predictably adjustable after implantation. It remains stable before and after Nd:YAG laser capsulotomy or after surgical adjustment of the refraction. This type of IOL may prove helpful especially in pediatric cataract surgery to avoid the development of amblyopia and in adults when precise refractive outcome is important either because of individual preference of the patient for a preferred refraction or because of intendend monovision to reduce spectacle dependence to a minimum. Commercial interest [source] | |||||||||||||||||||||||||