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Reasonable
Terms modified by Reasonable Selected AbstractsDue Diligence and "Reasonable Man," OffshoreCULTURAL ANTHROPOLOGY, Issue 4 2005Bill Maurer In the wake of an international crackdown against preferential tax regimes, Caribbean tax havens and other jurisdictions have adopted "due diligence" procedures to manage financial and reputational risk. Due diligence relies on qualitative forms of evaluation and defers grounded and definitive knowledge claims through continuous peer review. In doing so, it mirrors certain forms of ethnographic practice at a number of levels of scale. This article tracks the shifts in financial regulation from crime to harm and from certainty to scrutiny and reflects on their implications for ethnography,as a limited and open-ended process of evaluation warranted by qualitative forms of judgment. It seeks to complicate our picture of contemporary capitalisms by drawing attention to the nonquantifiable and the ethical that lie "inside" them. Where conventional forms of ethnographic critique might look to expose the political or economic interests behind actions, symbols, or social relationships, this article has a more modest goal: to try to understand the similarity of form between due diligence and anthropology. [source] Microcystic Adnexal Carcinoma Involving a Large Portion of the Face: When Is Surgery Not Reasonable?DERMATOLOGIC SURGERY, Issue 11 2005Daniel Brian Eisen MD Background. We report a case of microcystic adnexal carcinoma (MAC) involving a large portion of the face, one of the largest of any MAC reported thus far in this area, and review the literature regarding the nature of the tumor and available treatments. We also review all of the reported cases of metastases and the possible role of radiation in the etiopathogenesis of this tumor. Objective. To review the literature about what is known about therapy for MAC and what options are available to patients who have this disease. Materials and Methods. Case report and review of the literature. Results. Of the 274 cases of MAC thus far reported, there are 6 cases of metastases, only 1 of which resulted in death. Conclusion. Mohs surgery should be the treatment of choice for this tumor; however, when extirpation entails sufficiently large morbidity, given the low rate of metastases and mortality, observation is a reasonable alternative. DANIEL BRIAN EISEN, MD, AND DAVID ZLOTY, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source] Divide and Conquer: Separating the Reasonable from the UnreasonableJOURNAL OF SOCIAL PHILOSOPHY, Issue 1 2001Shaun P. Young [source] The nonprofit leadership deficit: A case for more optimismNONPROFIT MANAGEMENT & LEADERSHIP, Issue 3 2009Janet L. Johnson Recent headlines claim that a looming nonprofit leadership crisis will soon be precipitated by retiring baby boomers. Analysis of baby boom demographics, using national census data on the age distribution and other demographic characteristics of top leaders by sector, confirms the aging nonprofit workforce. However, the issue of whether the aging workforce portends a nonprofit leadership crisis, when analyzed within a theoretical framework of supply and demand in the market for nonprofit executives, reveals flaws in most commentaries about the leadership crisis. Workings of the labor market and nonprofit organizations themselves suggest trends that could be expected to affect labor supply and demand and mitigate a leadership deficit. Reasonable,and likely,market and organizational adjustments, including higher executive pay, increased labor force participation of older workers, skill acquisition of younger workers, possible consolidation of nonprofit organizations, board and volunteer skill sharing, and even venture philanthropy, can be expected to moderate the shock of baby boom retirements, much in the way that schools, job markets, and housing markets have accommodated the movement of this "bulging" generation through earlier decades of their lives. [source] II,Reflections on the Reasonable and the Rational in Conflict ResolutionARISTOTELIAN SOCIETY SUPPLEMENTARY VOLUME, Issue 1 2009Ruth Chang Most familiar approaches to social conflict moot reasonable ways of dealing with conflict, ways that aim to serve values such as legitimacy, justice, morality, fairness, fidelity to individual preferences, and so on. In this paper, I explore an alternative approach to social conflict that contrasts with the leading approaches of Rawlsians, perfectionists, and social choice theorists. The proposed approach takes intrinsic features of the conflict,what I call a conflict's evaluative ,structure',as grounds for a rational way of responding to that conflict. Like conflict within a single person, social conflict can have a distinctive evaluative structure that supports certain rational responses over others. I suggest that one common structure in both intra- and interpersonal cases of conflict supports the rational response of ,self-governance'. Self-governance in the case of social conflict involves a society's deliberating over the question, ,What kind of society should we be?' In liberal democracies, this rational response is also a reasonable one. [source] Recurrence of kernicterus in term and near-term infants in DenmarkACTA PAEDIATRICA, Issue 10 2000F Ebbesen Classical acute bilirubin encephalopathy (kernicterus) in term and near-term infants had not been seen in Denmark for at least 20 y until 1994. From 1994 to 1998, however, six cases were diagnosed. Aetiology of the hyperbilirubinaemia was known in two infants; spherocytosis and galactosaemia, most likely known in two infants; possible A-O blood type immunization, and unknown in two infants. However, one of these last-mentioned infants had a gestational age of only 36 wk. The maximum plasma total bilirubin concentrations were 531,745 ,mol/L. The increase in the number of cases of kernicterus was considered to have been caused by: (i) a decreased awareness of the pathological signs, (ii) a change in the assessment of the risk of bilirubin encephalopathy, (iii) early discharge of the infants from the maternity ward, (iv) so-called breastfeeding-associated jaundice, (v) demonstration of bilirubin being an antioxidant, and (vi) difficulty in estimating the degree of jaundice in certain groups of immigrants. Accordingly, for prevention: (a) Attempt to change the healthcare workers' understanding of the risk of bilirubin encephalopathy, (b) give further instructions, both orally and in writing, to mothers before discharge from the maternity ward, (c) be more liberal in giving infant formula supplements, (d) conduct home visits by the community nurse at an earlier stage, (e) follow authorized guidelines for phototherapy and exchange transfusion, (f) lower plasma bilirubin concentration limits as an indication for phototherapy and exchange transfusion, (g) screen all term and near-term infants, and (h) measure the skin's yellow colour with a device that corrects for the skin's melanin content. Conclusions: Audit of the six cases presented indicates that measures are necessary in both the primary and secondary healthcare sectors if the risk of kernicterus is to be avoided. Screening may be considered, but in order to identify the problems it would first be reasonable to perform a larger prospective study in which audit is performed on all newborn infants, born at term and near-term, who develop a plasma bilirubin concentration above the exchange transfusion limit. [source] Total nucleated cell differential for blood and bone marrow using a single tube in a five-color flow cytometer,,CYTOMETRY, Issue 2 2008Sven Björnsson Abstract Background: Flow cytometry allows the use of several antibodies in addition to light scatter, and most flow cytometers will provide at least seven measurements on each cell passing through the laser beam. A skilled microscopist will classify at least 14 cell classes in bone marrow or blood. Our goal was to use the seven parameters available in our flow cytometer to provide a reliable differential count using only one tube. Methods: Peripheral blood samples were analyzed on the Beckman Coulter LH750 cell counter, and the flagging and messages from the cell counter were used to select normal or pathological samples. Samples without flags (N = 50), with >2% erythroblasts (N = 80), or with "Blast" or "Verify diff" flags (N = 54) were investigated. We used a lyse-no-wash method to ensure minimal loss of fragile cells with live gating on DRAQ5-positive cells to acquire only nucleated cells. The FL-1 to FL-4 channels were used for the antibodies CD36-FITC, CD203-PE, CD138-PE, CD45-ECD, CD16-Pcy5, and CD56-Pcy5. FL-5 was used for the DNA-stain DRAQ5. Results: Using live gate acquisition on DRAQ5, we were able to classify total nucleated cells into 10 classes. We were unable to identify megakaryocytes, but platelets could be studied by rerunning the sample after dilution and gating on DRAQ5-negative CD36-posive events. Validation against digitized microscopy and cell counter showed linear correlations within each cell class with correlation coefficients that seem reasonable for cellular classification. The lowest correlation was found for basophil granulocytes. Flow cytometry detected twice as many immature neutrophils compared to microscopy. Conclusions: We have designed a one-tube immunophenotyping panel for classification of total nucleated cells and platelets in blood or bone marrow. The seven parameters available in one single tube in our cytometer seem to be enough for reliable differential count even in difficult pathological samples. The analytical imprecision of the flow cytometer differential was much lower than that obtained with microscopy or cell counter differentials. © 2007 Clinical Cytometry Society. [source] Applications of cone-beam computed tomography in fractures of the maxillofacial complexDENTAL TRAUMATOLOGY, Issue 4 2009Werner H. Shintaku Several studies support the use of conventional two-dimensional imaging for traumas involving mainly the mandible, but for more complex situations advanced imaging modalities such as computed tomography (CT) and magnetic resonance imaging have higher indication. Nowadays, besides CT, cone-beam computed tomography (CBCT) has appeared as a reasonable and reliable alternative considering radiation dosage, image quality and comfort for the patient. The purpose of this study was to review the fracture patterns involving the maxillofacial complex, provide a technical and practical comparison between CT and CBCT, and finally present the potential applications of CBCT illustrated with clinical examples. [source] Bapx1 homeobox gene gain-of-function mice show preaxial polydactyly and activated Shh signaling in the developing limbDEVELOPMENTAL DYNAMICS, Issue 9 2006Carla Tribioli Abstract To explore Bapx1 homeobox gene function in embryonic control of development, we employed a gain-of-function approach to complement our previous loss-of-function mutant analysis. We show that transgenic mice overexpressing Bapx1 are affected by skeletal defects including hindlimb preaxial polydactyly and tibial hypoplasia. Bapx1 overexpression generates limb anteroposterior patterning defects including induction of Shh signaling and ectopic activation of functions downstream of Shh signaling into the anterior region of the autopod. Moreover, Bapx1 overexpression stimulates formation of limb prechondrogenic condensations. We also show that Shh is reciprocally able to activate Bapx1 expression in mouse embryos as the orthologous hedgehog (hh) does with the bagpipe/Bapx1 gene in Drosophila. Our results indicate that Bapx1 can modulate appendicular skeletal formation, that the genetic hierarchy between Shh/hh and Bapx1/bagpipe has been conserved during evolution, and that in mouse embryos these two genes can influence one another in a genetically reciprocal manner. We conclude that it is reasonable to expect overexpression of Bapx1 in certain forms of polydactyly. Developmental Dynamics 235:2483,2492, 2006. © 2006 Wiley-Liss, Inc. [source] Hippocampal lesions impair spatial memory performance, but not song,A developmental study of independent memory systems in the zebra finchDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2009David J. Bailey Abstract Songbirds demonstrate song- and spatial-learning, forms of memory that appear distinct in formal characteristics and fitting the descriptions and criteria of procedural and episodic-like memory function, respectively. As in other vertebrates, the neural pathways underlying these forms of memory may also be dissociable, and include the corresponding song circuit and hippocampus (HP). Whether (or not) these two memory systems interact is unknown. Interestingly, the HP distinguishes itself as a site of immediate early gene expression in response to song and as a site of estrogen synthesis, a steroid involved in song learning. Thus, an interaction between these memory systems and their anatomical substrates appears reasonable to hypothesize, particularly during development. To test this idea, juvenile male or female zebra finches received chemical lesions of the HP at various points during song learning, as did adults. Song structure, singing behavior, song preference, and spatial memory were tested in adulthood. Although lesions of the HP severely compromised HP-dependent spatial memory function across all ages and in both sexes, we were unable to detect any effects of HP lesions on song learning, singing, or song structure in males. Interestingly, females lesioned as adults, but not as juveniles, did lose the characteristic preference for their father's song. Since compromise of the neural circuits that subserve episodic-like memory does very little (if anything) to affect procedural-like (song learning) memory, we conclude that these memory systems and their anatomical substrates are well dissociated in the developing male zebra finch. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] STANDARDIZATION OF ENDOSCOPIC ULTRASONOGRAPHY PROCEDURES FOR THE PANCREAS USING RADIAL and CONVEX methodsDIGESTIVE ENDOSCOPY, Issue 2002Yoshiki Hirooka We describe the standard endoscopic ultrasonography (EUS) procedure of the pancreas used in our institute. Both radial scanning and convex (or linear) scanning methods have valid uses, so these two methods will coexist in the future. Physicians learning EUS need to master both types. It is important to standardize both types of EUS procedure. Generally, physicians persist in the method mastered first and don't make use of the other method. In order to plan the standardization of EUS procedures, it may be reasonable to standardize the procedures of both type EUS simultaneously, comparing radial scan mode and linear (convex) scan mode. Here we demonstrate our standard procedures for both EUS modes, mainly emphasizing the visualization maneuver of the pancreas. [source] Correlation model for spatially distributed ground-motion intensitiesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 15 2009Nirmal Jayaram Abstract Risk assessment of spatially distributed building portfolios or infrastructure systems requires quantification of the joint occurrence of ground-motion intensities at several sites, during the same earthquake. The ground-motion models that are used for site-specific hazard analysis do not provide information on the spatial correlation between ground-motion intensities, which is required for the joint prediction of intensities at multiple sites. Moreover, researchers who have previously computed these correlations using observed ground-motion recordings differ in their estimates of spatial correlation. In this paper, ground motions observed during seven past earthquakes are used to estimate correlations between spatially distributed spectral accelerations at various spectral periods. Geostatistical tools are used to quantify and express the observed correlations in a standard format. The estimated correlation model is also compared with previously published results, and apparent discrepancies among the previous results are explained. The analysis shows that the spatial correlation reduces with increasing separation between the sites of interest. The rate of decay of correlation typically decreases with increasing spectral acceleration period. At periods longer than 2,s, the correlations were similar for all the earthquake ground motions considered. At shorter periods, however, the correlations were found to be related to the local-site conditions (as indicated by site Vs30 values) at the ground-motion recording stations. The research work also investigates the assumption of isotropy used in developing the spatial correlation models. It is seen using the Northridge and Chi-Chi earthquake time histories that the isotropy assumption is reasonable at both long and short periods. Based on the factors identified as influencing the spatial correlation, a model is developed that can be used to select appropriate correlation estimates for use in practical risk assessment problems. Copyright © 2009 John Wiley & Sons, Ltd. [source] On-line hybrid test combining with general-purpose finite element softwareEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 12 2006Tao Wang Abstract A new on-line hybrid test system incorporated with the substructuring technique is developed. In this system, a general-purpose finite element software is employed to obtain the restoring forces of the numerical substructure accurately. The restart option is repeatedly used to accommodate the software with alternating loading and analysis characteristic of the on-line test but without touching the source code. An eight-storey base-isolated structure is tested to evaluate the feasibility and effectiveness of the proposed test system. The overall structure is divided into two substructures, i.e. a superstructure to be analysed by the software and a base-isolation layer to be tested physically. Collisions between the base-isolation layer and the surrounding walls are considered in the test. The responses of the overall structure are reasonable, and smooth operation is achieved without any malfunction. Copyright © 2006 John Wiley & Sons, Ltd. [source] Seismic performance and new design procedure for chevron-braced framesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 4 2006Edoardo M. Marino Abstract The paper is concerned with the seismic design of steel-braced frames in which the braces are configured in a chevron pattern. According to EuroCode 8 (EC8), the behaviour factor q, which allows for the trade-off between the strength and ductility, is set at 2.5 for chevron-braced frames, while 6.5 is assigned for most ductile steel moment-resisting frames. Strength deterioration in post-buckling regime varies with the brace's slenderness, but EC8 adopts a unique q value irrespective of the brace slenderness. The study focuses on reevaluation of the q value adequate for the seismic design of chevron-braced frames. The present EC8 method for the calculation of brace strength supplies significantly different elastic stiffnesses and actual strengths for different values of brace slenderness. A new method to estimate the strength of a chevron brace pair is proposed, in which the yield strength (for the brace in tension) and the post-buckling strength (for the brace in compression) are considered. The new method ensures an identical elastic stiffness and a similar strength regardless of the brace slenderness. The advantage of the proposed method over the conventional EC8 method is demonstrated for the capacity of the proposed method to control the maximum inter-storey drift. The q values adequate for the chevron-braced frames are examined in reference to the maximum inter-storey drifts sustained by most ductile moment-resisting frames. When the proposed method is employed for strength calculation, the q value of 3.5 is found to be reasonable. It is notable that the proposed method does not require larger cross-sections for the braces compared to the cross-sections required for the present EC8 method. Copyright © 2005 John Wiley & Sons, Ltd. [source] Modelling species distributions in Britain: a hierarchical integration of climate and land-cover dataECOGRAPHY, Issue 3 2004Richard G. Pearson A modelling framework for studying the combined effects of climate and land-cover changes on the distribution of species is presented. The model integrates land-cover data into a correlative bioclimatic model in a scale-dependent hierarchical manner, whereby Artificial Neural Networks are used to characterise species' climatic requirements at the European scale and land-cover requirements at the British scale. The model has been tested against an alternative non-hierarchical approach and has been applied to four plant species in Britain: Rhynchospora alba, Erica tetralix, Salix herbacea and Geranium sylvaticum. Predictive performance has been evaluated using Cohen's Kappa statistic and the area under the Receiver Operating Characteristic curve, and a novel approach to identifying thresholds of occurrence which utilises three levels of confidence has been applied. Results demonstrate reasonable to good predictive performance for each species, with the main patterns of distribution simulated at both 10 km and 1 km resolutions. The incorporation of land-cover data was found to significantly improve purely climate-driven predictions for R. alba and E. tetralix, enabling regions with suitable climate but unsuitable land-cover to be identified. The study thus provides an insight into the roles of climate and land-cover as determinants of species' distributions and it is demonstrated that the modelling approach presented can provide a useful framework for making predictions of distributions under scenarios of changing climate and land-cover type. The paper confirms the potential utility of multi-scale approaches for understanding environmental limitations to species' distributions, and demonstrates that the search for environmental correlates with species' distributions must be addressed at an appropriate spatial scale. Our study contributes to the mounting evidence that hierarchical schemes are characteristic of ecological systems. [source] Comparison of soil moisture and meteorological controls on pine and spruce transpirationECOHYDROLOGY, Issue 3 2008Eric E. Small Abstract Transpiration is an important component of the water balance in the high elevation headwaters of semi-arid drainage basins. We compare the importance of soil moisture and meteorological controls on transpiration and quantify how these controls are different at a ponderosa pine site and a spruce site in the Jemez river drainage basin of northern New Mexico, a sub-basin of the Rio Grande. If only soil moisture controls fluctuations in transpiration, then simple hydrologic models focussed only on soil moisture limitations are reasonable for water balance studies. If meteorological controls are also critical, then more complex models are required. We measured volumetric water content in the soil and sap velocity, and assumed that transpiration is proportional to sap velocity. Ponderosa sap velocity varies with root zone soil moisture. Nearly all of the scatter in the ponderosa sap velocity,soil moisture relationship can be predicted using a simple model of potential evapotranspiration (ET), which depends only on measured incident radiation and air temperature. Therefore, simple hydrologic models of ponderosa pine transpiration are warranted. In contrast, spruce sap velocity does not clearly covary with soil moisture. Including variations in potential evapotranspiration does not clarify the relationship between sap velocity and soil moisture. Likewise, variations in radiation, air temperature, and vapour pressure do not explain the observed fluctuations in sap velocity, at least according to the standard models and parameters for meteorological restrictions on transpiration. Both the simple and more complex models commonly used to predict transpiration are not adequate to model the water balance in the spruce forest studied here. Copyright © 2008 John Wiley & Sons, Ltd. [source] Anchoring Economic Predictions in Common KnowledgeECONOMETRICA, Issue 2 2002R. Guesnerie The paper examines within a unified methodology expectational coordination in a series of economic models. The methodology views the predictions associated with the Rational Expectations Hypothesis as reasonable whenever they can be derived from the more basic Common Knowledge Hypothesis. The paper successively considers a simple non-noisy N -dimensional model, standard models with "intrinsic" uncertainty, and reference intertemporal models with infinite horizon. It reviews existing results and suggests new ones. It translates the formal results into looser but economically intuitive statements, whose robustness, in the present state of knowledge, is tentatively ascertained. [source] Discrepancies Between Score Trends from NAEP and State Tests: A Scale-Invariant PerspectiveEDUCATIONAL MEASUREMENT: ISSUES AND PRACTICE, Issue 4 2007Andrew D. Ho State test score trends are widely interpreted as indicators of educational improvement. To validate these interpretations, state test score trends are often compared to trends on other tests such as the National Assessment of Educational Progress (NAEP). These comparisons raise serious technical and substantive concerns. Technically, the most commonly used trend statistics,for example, the change in the percent of proficient students,are misleading in the context of cross-test comparisons. Substantively, it may not be reasonable to expect that NAEP and state test score trends should be similar. This paper motivates then applies a "scale-invariant" framework for cross-test trend comparisons to compare "high-stakes" state test score trends from 2003 to 2005 to NAEP trends over the same period. Results show that state trends are significantly more positive than NAEP trends. The paper concludes with cautions against the positioning of trend discrepancies in a framework where only one trend is considered "true." [source] Procedural skills quality assurance among Australasian College for Emergency Medicine fellows and traineesEMERGENCY MEDICINE AUSTRALASIA, Issue 3 2006David McD Taylor Abstract Objective: Presently, no objective quality control mechanism exists for monitoring procedural skills among Australasian College for Emergency Medicine trainees. The present study examined trainee and fellow procedural experience and perceived competency, participation in accredited training courses and support for a procedural logbook. Methods: A cross-sectional mail survey of Australasian College for Emergency Medicine advanced trainees and fellows was performed. Experience and perceived competency in 23 common and important ED procedures were examined. Results: In total, 202 fellows and 264 trainees responded (overall response rate 39.0%). Overall, fellow procedural experience and perceived competency were reasonable. However, some fellows had never performed a number of procedures including some common procedures (e.g. nasal packing, fracture reduction) and there were reports of ,very poor' competency for 17 (73.9%) procedures. Trainee experience and perceived competency were less than the fellows but showed similar patterns. Perceived numbers of each procedure required to achieve competency varied considerably between the procedures and among the respondents. However, there were no significant differences in the perceived numbers reported by the trainees and the fellows (P > 0.05). Variable proportions of trainees and fellows had undertaken courses that incorporated procedural skills training. More fellows (75.7%, 95% confidence interval 69.1,81.4) than trainees (59.9%, 95% confidence interval 53.6,65.8) supported the use of a procedural logbook (P = 0.003). Conclusions: Lack of experience in some procedures among some fellows, especially commonly performed procedures, might represent a deficiency in existing quality assurance mechanisms for procedural skills training. Greater participation in skills courses, to improve experience in difficult and uncommonly encountered procedures, is recommended. Improved quality assurance mechanisms, including a procedural logbook, should be considered. [source] A brief overview of mechanisms of mitochondrial toxicity from NRTIs,ENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 3-4 2007James J. Kohler Abstract Nucleoside reverse transcriptase inhibitors (NRTIs) in combinations with other antiretrovirals (highly active antiretroviral therapy, HAART) are the cornerstones of AIDS therapy, turning HIV infection into a manageable clinical entity. Despite the initial positive impact of NRTIs, therapeutic experience revealed serious side effects that appeared to originate in the mitochondria and which ultimately manifested as dysfunction of that organelle. It may be reasonable to consider that as the AIDS epidemic continues and as survival with HIV infection is prolonged by treatment with HAART, long-term side effects of NRTIs may become increasingly common. This consideration may be underscored in children who are born to HIV-infected mothers who received NRTI therapy in utero during gestation. The long-term effect of that NRTI exposure in utero is not clear yet. This review examines some proposed mechanisms of NRTI mitochondrial toxicity, including genetic predisposition, defects in mitochondria DNA replication, the encompassing "DNA pol-, hypothesis," the relationship between mitochondrial nucleotide and NRTI pools, mitochondrial DNA mutation and dysfunction, and oxidative stresses related to HIV infection and NRTIs. Mechanisms of mitochondrial toxicity are reviewed with respect to key cell biological, pathological, and pharmacological events. Environ. Mol. Mutagen., 2006. © 2006 Wiley-Liss, Inc. [source] Difference in the sensitivity to chemical compounds between female and male neonates of Daphnia magnaENVIRONMENTAL TOXICOLOGY, Issue 5 2008Erika Ikuno Abstract Daphnia magna usually produce female offspring by parthenogenesis, and thus only female neonates are used to evaluate the environmental toxicity to chemicals. Additionally, it is known that male daphnids are induced by exposure to a juvenile hormone, methyl farnesoate, during late ovarian development. In this study, we investigated the concentration of methyl farnesoate in a 24-h exposure producing 100% males, and the difference in sensitivity to chemical compounds, potassium dichromate, pentachlorophenol, and paraquat, between females and males, referring to OECD Test Guideline 202. The results show that the minimum concentration for 100%-male induction of methyl farnesoate in adult females was 50 ,g/L. In addition, acute toxicity tests (immobility test) with the other chemicals showed that male neonates have higher tolerance to potassium dichromate and pentachlorophenol than females for at least 24 h after birth, while no sex difference was observed in the sensitivity to paraquat. The differences in the median effective concentrations in these compounds between female and male neonates suggest two different overall modes of action. Using female daphnids for environmentally toxicity testing seems reasonable, since the females are more sensitive to chemicals than males. Furthermore, the method of male induction established in this study could be used for screening of endocrine disruptors. © 2008 Wiley Periodicals, Inc. Environ Toxicol, 2008. [source] Partition Behavior of Polycyclic Aromatic Hydrocarbons Between Aged Coal Tar and Water,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2009Lihua Liu Abstract Coal tar aged in a large-scale, artificial aquifer experiment for five years was subsequently investigated for leaching behavior of polycyclic aromatic hydrocarbons (PAHs). After five years, the initially liquid coal tar had solidified and formed segregated particles with a grain size similar to that of the sandy aquifer material. The composition of the aged coal tar (ACT) with regard to PAHs was remarkably different from that of the original bulk coal tar (BCT), because most of the low-molecular-weight compounds had been depleted. Equilibrium aqueous-phase concentrations of 17 PAHs leaching from the aquifer material containing the ACT were measured from consecutive equilibration steps at increasing temperatures of between 25 and 100C using accelerated solvent extraction. The results showed 2-to 5,000-fold lower concentrations than those from BCT, indicating dramatic changes of dissolution behavior of PAHs from coal tar after the five-year aging period. Predictions based on Raoult's law with the subcooled liquid solubilities substantially overestimated the equilibrium aqueous-phase concentrations of the PAHs from ACT, whereas the estimations were reasonable if the solid solubilities were employed instead. The enthalpies of phase transfer from ACT to water were determined based on the van't Hoff equation. The resulting values agreed with the dissolution enthalpies of pure solid rather than subcooled liquid PAHs. [source] A review of potential methods of determining critical effect size for designing environmental monitoring programs,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2009Kelly R. Munkittrick Abstract The effective design of field studies requires that sample size requirements be estimated for important endpoints before conducting assessments. This a priori calculation of sample size requires initial estimates for the variability of the endpoints of interest, decisions regarding significance levels and the power desired, and identification of an effect size to be detected. Although many programs have called for use of critical effect sizes (CES) in the design of monitoring programs, few attempts have been made to define them. This paper reviews approaches that have been or could be used to set specific CES. The ideal method for setting CES would be to define the level of protection that prevents ecologically relevant impacts and to set a warning level of change that would be more sensitive than that CES level to provide a margin of safety; however, few examples of this approach being applied exist. Program-specific CES could be developed through the use of numbers based on regulatory or detection limits, a number defined through stakeholder negotiation, estimates of the ranges of reference data, or calculation from the distribution of data using frequency plots or multivariate techniques. The CES that have been defined often are consistent with a CES of approximately 25%, or two standard deviations, for many biological or ecological monitoring endpoints, and this value appears to be reasonable for use in a wide variety of monitoring programs and with a wide variety of endpoints. [source] Bilinear estimation of pollution source profiles and amounts by using multivariate receptor modelsENVIRONMETRICS, Issue 7 2002Eun Sug Park Abstract Multivariate receptor models aim to identify the pollution sources based on multivariate air pollution data. This article is concerned with estimation of the source profiles (pollution recipes) and their contributions (amounts of pollution). The estimation procedures are based on constrained nonlinear least squares methods with the constraints given by nonnegativity and identifiability conditions of the model parameters. We investigate several identifiability conditions that are appropriate in the context of receptor models, and also present new sets of identifiability conditions, which are often reasonable in practice when the other traditional identifiability conditions fail. The resulting estimators are consistent under appropriate identifiability conditions, and standard errors for the estimators are also provided. Simulation and application to real air pollution data illustrate the results. Copyright © 2002 John Wiley & Sons, Ltd. [source] Navigating toward Fetal and Maternal Health: The Challenge of Treating Epilepsy in PregnancyEPILEPSIA, Issue 10 2004Torbjörn Tomson Summary:, A rational approach to the treatment of women of childbearing potential with epilepsy has been hampered by the lack of conclusive data on the comparative teratogenic potential of different antiepileptic drugs (AEDs). Although, several cohort studies on birth defects associated with AED use during pregnancy have been published, these have generally failed to demonstrate differences in malformation rates between AEDs, probably mainly due to insufficient power. In particular, pregnancies with new generation AEDs have been too few. In recent years, pregnancy registries have been introduced to overcome this problem,EURAP (an international collaboration), the North American, and the U.K. AED and pregnancy registries are observational studies that prospectively assess pregnancy outcome after AED exposure using slightly different methods. Each has enlisted 3,5,000 pregnancies in women with epilepsy, and the North American and the U.K. have released preliminary observations. Thus the U.K. registry reported a higher malformation rate with valproate, 5.9% (4.3,8.2%; 95% CI), than with carbamazepine, 2.3% (1.4,3.7%), and lamotrigine, 2.1% (1.0,4.0%). Most of the more recent cohort studies have also identified a nonsignificant trend toward a higher teratogenicity with valproate. These signals need to be interpreted with some caution since none of the studies to date have fully assessed the impact of possible confounders, such as type of epilepsy, family history of birth defects, etc. However, with increasing number of pregnancies it should be possible in the near future for the pregnancy registries to take such confounding factors into account and thus make more reliable assessments of the causal relationship between exposure to specific AEDs and teratogenic risks. While awaiting more conclusive results, it appears reasonable to be cautious in prescribing valproate to women considering to become pregnant if other suitable treatment alternatives, and with less teratogenic potential, are available. Any attempt to change treatment should, however, be accomplished well before conception. The importance of maintained seizure control must also be kept in mind, and the woman who needs valproate to control her seizures should not be discouraged from pregnancy, provided that counseling at the best of available knowledge is given. [source] Nursing Synchronization and Milk Ejection Failure as Maternal Strategies to Reduce Allosuckling in Pair-Housed Sows (Sus scrofa domestica)ETHOLOGY, Issue 7 2005Gudrun Illmann Non-offspring nursing (allosuckling) is costly for lactating females. It is reasonable to assume, therefore, that mechanisms have evolved to control the frequency of allosuckling. It is suggested that the synchronization of nursing between females could be such a mechanism. The aim of this study was to investigate whether nursing synchronization is related to the timing of nursing behaviour of paired sows and the behaviour of alien piglets in relation to allosuckling. Specifically, we predicted that: (i) nursing synchronization will increase if there is a real risk of allosuckling compared with a situation where there is none, (ii) nursing synchronization indeed reduces allosuckling and, therefore, those nursings with allosuckling attempts will be less closely synchronized than those without allosuckling attempts and (iii) in non-synchronized nursings, the sows will more often employ another strategy to reduce allosuckling, namely, they will make the nursings non-nutritive by not releasing milk. Ten pairs of sows and their litters were used in this study. For each pair, the two sows were housed individually until their litters were weaned; however, their litters had access to both sows from day 11 post-partum. The behaviour of the 10 pairs of sows with their litters was videotaped for 6 h on days 10, 11, 17 and 24 post-partum. The frequency of allosuckling attempts, non-nutritive nursings and allosuckling during milk ejection was analysed for every pair for every day of observation. The observed frequency of nursing synchronization was high. The median interval between the start of a nursing within one pair of sows was 32 s. The first prediction was supported as synchronization became significantly tighter when piglets were given the possibility to allosuckle on day 11 [Cochran,Mantel,Haenszel (CMH) statistics, p < 0.0001]. The second prediction was also supported; the nursings were less closely synchronized when there were allosuckling attempts (CMH statistics, p < 0.05). Of all nursings, 36% had an allosuckling attempt; however, only 17% resulted in real allosuckling. Evidence in favour of the third prediction was also found as non-nutritive nursings were more frequent in non-synchronized nursings (CMH statistics, p < 0.05). Finally, real allosuckling during milk ejection was unrelated to the degree of nursing synchronization, as in less synchronized nursings, the sows responded to allosuckling attempts by not releasing milk. Our results suggest that sows are not able to completely suppress allosuckling; however, they can reduce its frequency through nursing synchronization and non-nutritive nursings. [source] Highly Crystalline, Idiomorphic Na2Ti6O13 Whiskers Grown from a NaCl Flux at a Relatively Low TemperatureEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2010Katsuya Teshima Abstract Well-developed, highly crystalline Na2Ti6O13 whiskers were successfully grown by cooling a NaCl flux at a relatively low temperature of 700 °C. The obtained Na2Ti6O13 whiskers were colorless and transparent. The whiskers grown at 700 °C were single phase and exhibit the lowest sizes of up to about 3.5 ,m,×,0.1 ,m. From the results of SEM, XRD, and TEM, it was confirmed that the Na2Ti6O13 whiskers have very good crystallinity and elongated in the [lang]010[rang] directions. Furthermore, the whiskers exhibited good photocatalytic activity under ultraviolet light irradiation. It is reasonable to suppose that NaCl can be adequately used to synthesize high quality and well-developed titanate whiskers in an environmentally friendly process of crystal growth. [source] Astrocytes in the hippocampus of patients with temporal lobe epilepsy display changes in potassium conductancesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2000Stefan Hinterkeuser Abstract Functional properties of astrocytes were investigated with the patch-clamp technique in acute hippocampal brain slices obtained from surgical specimens of patients suffering from pharmaco-resistant temporal lobe epilepsy (TLE). In patients with significant neuronal cell loss, i.e. Ammon's horn sclerosis, the glial current patterns resembled properties characteristic of immature astrocytes in the murine or rat hippocampus. Depolarizing voltage steps activated delayed rectifier and transient K+ currents as well as tetrodotoxin-sensitive Na+ currents in all astrocytes analysed in the sclerotic human tissue. Hyperpolarizing voltages elicited inward rectifier currents that inactivated at membrane potentials negative to -130 mV. Comparative recordings were performed in astrocytes from patients with lesion-associated TLE that lacked significant histopathological hippocampal alterations. These cells displayed stronger inward rectification. To obtain a quantitative measure, current densities were calculated and the ratio of inward to outward K+ conductances was determined. Both values were significantly smaller in astrocytes from the sclerotic group compared with lesion-associated TLE. During normal development of rodent brain, astroglial inward rectification gradually increases. It thus appears reasonable to suggest that astrocytes in human sclerotic tissue return to an immature current pattern. Reduced astroglial inward rectification in conjunction with seizure-induced shrinkage of the extracellular space may lead to impaired spatial K+ buffering. This will result in stronger and prolonged depolarization of glial cells and neurons in response to activity-dependent K+ release, and may thus contribute to seizure generation in this particular condition of human TLE. [source] Highly Efficient and Practical Pyrrolidine,Camphor-Derived Organocatalysts for the Direct ,-Amination of AldehydesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2010Pang-Min Liu Abstract A series of pyrrolidine,camphor-derived organocatalysts (1,4) were designed and synthesised. These organocatalysts were used for direct ,-amination of aldehydes with dialkyl azodicarboxylates to give the desired ,-aminated products in high chemical yields (up to 92,%) and with high to excellent levels of stereoselectivity (up to >99,% ee). The reactions proceeded rapidly (within 5 min) with low catalyst loading (5 mol-%) at ambient temperature. Enantioselective aminations of asymmetric ,,,-disubstituted aldehydes in the catalytic system were studied, with reasonable to high stereoselectivities (up to 75,% ee) being obtained. The utility of this methodology was demonstrated with the synthesis of derivatives of ,-amino-,-butyrolactone and a tetrasubstitutedcyclohexane-derived amino alcohol with high stereoselectivities. Transition models were proposed for the asymmetric ,-amination reactions; they involve hydrogen-bond interactions between the nucleophilic enamine formed in situ and the nitrogen source. [source] A view of extraterrestrial soilsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 6 2009G. Certini Summary The nature of soils on celestial bodies other than Earth is a growing area of research in planetary geology. However, disagreement over the significance of these deposits arises, in part, through the lack of a unified concept and definition of soil in the literature. The pragmatic definition ,medium for plant growth' is taken by some to imply the necessity of biota for soil to exist, and has been commonly adopted in the planetary science community. In contrast, a more complex and informative definition is based on scientific theory: soil is the (bio)geochemically/physically altered material at the surface of a planetary body that encompasses surficial extraterrestrial telluric deposits. This definition is based on the premise that soil is a body that retains information about its environmental history and that it does not need the presence of life to form. Four decades of missions have gathered geochemical information regarding the surface of planets and bodies within the Solar System, and information is quickly increasing. Reviewing the current knowledge on properties of extraterrestrial regoliths, we conclude that the surficial deposits of Venus, Mars and our moon should be considered to be soils in a pedological sense, and that Mercury and some large asteroids are covered in mantles that are soil candidates. A key environmental distinction between Earth and other Solar System bodies is the presence of life, and because of this dissimilarity in soil-forming processes, it is reasonable to distinguish these (presently) abiotic soils as Astrosols. Attempts to provide detailed classifications of extraterrestrial soils are premature, given our poor current knowledge of the Universe, but they highlight the fact that Earth possesses almost-abiotic environments that lend themselves to providing more understanding about telluric bodies of the Solar System. "He found himself in the neighbourhood of the asteroids 325, 326, 327, 328, 329, and 330. He began, therefore, by visiting them, in order to add to his knowledge." (Excerpt from the The Little Prince by Antoine de Saint-Exupéry) [source] | |||||||||||||||||||||||||||||||||||||||||||||||||