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Selected AbstractsHow Does the Gender of Parents Matter?JOURNAL OF MARRIAGE AND FAMILY, Issue 1 2010Timothy J. Biblarz Claims that children need both a mother and father presume that women and men parent differently in ways crucial to development but generally rely on studies that conflate gender with other family structure variables. We analyze findings from studies with designs that mitigate these problems by comparing 2-parent families with same or different sex coparents and single-mother with single-father families. Strengths typically associated with married mother-father families appear to the same extent in families with 2 mothers and potentially in those with 2 fathers. Average differences favor women over men, but parenting skills are not dichotomous or exclusive. The gender of parents correlates in novel ways with parent-child relationships but has minor significance for children's psychological adjustment and social success. [source] The case for venous rather than arterial blood gases in diabetic ketoacidosisEMERGENCY MEDICINE AUSTRALASIA, Issue 1 2006Anne-Maree Kelly Abstract Objectives:, For patients with diabetic ketoacidosis (DKA), arterial blood gas (BG) sampling for measurement of pH and bicarbonate has been considered an essential part of initial evaluation and monitoring of progress. There is growing evidence that venous values can be clinically acceptable alternatives to arterial measurements. This article summarizes the recent evidence regarding the validity of venous BG sampling in DKA. Methods:, Medline search for the years 1995 to present, hand search of reference lists, search of on-line evidence-based medicine sites. Results:, In patients with DKA the weighted average difference between arterial and venous pH was 0.02 pH units (95% limits of agreement ,0.009 to +0.021 pH units) and between arterial and venous bicarbonate was ,1.88 mEq/L. Conclusions:, There is reasonable evidence that venous and arterial pH have sufficient agreement as to be clinically interchangeable in patients with DKA who are haemodynamically stable and without respiratory failure. There is some evidence that venous and arterial bicarbonate also agree closely in DKA but this requires confirmation. [source] Agreement between bicarbonate measured on arterial and venous blood gasesEMERGENCY MEDICINE AUSTRALASIA, Issue 5-6 2004Anne-Maree Kelly Abstract Objective:, This study aims to determine the extent of agreement between venous and arterial bicarbonate for a group of emergency department patients with respiratory or metabolic illness requiring blood gas analysis as part of their evaluation. Methods:, This prospective study of patients who were deemed by their treating doctor to require an arterial blood gas analysis to determine their ventilatory or acid-base status, compared bicarbonate on an arterial and a venous sample taken as close to simultaneously as possible. Data were analysed using bias (Bland-Altman) methods. Subgroup analyses were performed for the metabolic, respiratory, chronic obstructive airways disease and acidotic subgroups. Results:, Two hundred and forty-six patients were entered into the study; 195 with acute respiratory disease and 51 with suspected metabolic derangement. The values of bicarbonate on arterial and venous samples showed close agreement with an average difference between the samples of 1.20 mmol/L (95% limits of agreement being ,2.73 to +5.13 mmol/L). Similar agreement was found for all subgroups. Conclusion:, Venous bicarbonate estimation shows a high level of agreement with the arterial value, with acceptably narrow 95% limits of agreement. These results suggest that venous bicarbonate estimation may be an acceptable substitute for arterial measurement. [source] A Comparison of Cost of Equity Estimates of Local and Global CAPMsFINANCIAL REVIEW, Issue 4 2001Dev R. Mishra G12/G15/G32 Abstract Cost of equity estimates are compared for three pricing models: the traditional local CAPM, the single (market) factor global CAPM, and the two-factor global CAPM, with both market and currency index factors. For 2989 US stocks, the average difference in the cost of equity estimates is about 48 basis points between the local CAPM and the single-factor global CAPM, and is about 61 basis points between the two global models. For 70 developed-market ADRs, the corresponding average differences are 76 and 47 basis points, respectively. For 48 emerging-market ADRs, the corresponding average differences are 57 and 70 basis points. [source] Balances of phosphorus and nitrogen in carp pondsFISHERIES MANAGEMENT & ECOLOGY, Issue 1-2 2000R. Knösche The impact of carp pond effluents on natural waters was investigated in the German federal states of Brandenburg, Saxony and Bavaria, and in Hungary. Data from 38 ponds (size = 0.25,122 ha) were available for the calculation of inlet,outlet differences. An average difference of 0.51 kg phosphorus (P) ha,1 year,1 was obtained. This means that every hectare of pond surface releases 510 g P less than it receives from the incoming water. This result was independent of the amount of fish harvested (, 1500 ha,1 year,1). The average retention of P (P-balance) was 5.71 kg P ha,1 year,1. Phosphorus retention increased with increasing intensity of production. Nitrogen (N) retention increased with production intensity from 78.5 kg ha,1 year,1 in German standard ponds to >,290 kg N ha,1 year,1in pig-cum-fish ponds in Hungary. A predominantly mineralized sludge suspension is released during harvesting at loads below 1% of the retention capacity of the pond. Under usual pond management regimes, the sludge load during harvesting ranged from 50 to 200 L ha,1, equivalent to 0.3,9.3 g dry matter ha,1. The present study suggests that ponds are not a burden on the environment. By contrast, these water bodies improve water quality. Therefore, pressures to reduce the intensity of pond production cannot be justified on the basis of supposed impacts on water quality. However, even if loads during harvesting are low compared with the retention capacity of the pond, more effort should be carried out to reduce the pollution of streams by pond outlets downstream. This can be done by limiting pond drainage to periods when the suspended material has settled or by short-term sedimentation of the sludge in a settling pond downstream of the rearing facility. [source] ,15N of zooplankton species in subarctic lakes in northern Sweden: effects of diet and trophic fractionationFRESHWATER BIOLOGY, Issue 5 2004J. Karlsson Summary 1. To assess the use of stable nitrogen isotopes (,15N) for reconstructing trophic relationships in planktonic food webs, crustacean zooplankton species and pelagic dissolved and particulate matter were analysed in 14 subarctic lakes in northern Sweden. The lakes are situated along an altitudinal gradient and show a substantial variation in nutrient content and energy mobilization by bacterioplankton and phytoplankton. 2. The ,15N of dissolved and particulate matter was comparatively low, suggesting efficient N recycling and low losses of depleted N from the pelagic zone of these unproductive lakes. 3. Copepods had a systematically higher ,15N than cladocerans, with an average difference of 3.1,4.9, within lakes, implying different trophic positions of the two groups. Comparisons of nitrogen pools and energy fluxes suggest that the low cladoceran ,15N was a result of feeding on bacteria. 4. The difference in ,15N between copepods and cladocerans declined with decreasing bacterioplankton production among lakes, due either to increasing trophic isotope fractionation or decreasing relative importance of bacteria in the diet of cladocerans. [source] A preference-based index for the SF-12HEALTH ECONOMICS, Issue 6 2006D. Stratmann-Schoene Abstract Background: The SF-12 is a widely used generic measure of subjective health. As the scoring algorithms of the SF-12 do not include preference values, different approaches to assign a preference-based index are available that should be tested regarding their feasibility and validity. Objectives: To develop a concept for a preference-based index for the SF-12 on the basis of multi-attribute decision analysis and to perform initial tests of its feasibility and validity in an empirical study. Methods: A multi-attribute preference function for the SF-12 was developed, estimated and tested for validity. Two mail surveys (n = 100, 200) and an interview (n = 72) were conducted with women who had an operation for breast cancer. Visual analogue scale (VAS) and standard gamble (SG) measures elicited preference-based valuations. Results: Eight attributes were identified in the SF-12. Validity tests showed an average difference of 8 VAS score points between directly measured and predicted values for given health states. Conclusion: The initial results show that this approach might allow the direct assignment of a preference-based valuation to the SF-12. The quality of the psychometric features of the multi-attribute value function is encouraging. Future studies should test this concept more extensively, especially by determining parameters for a representative sample of the general population and by comparing performance with other approaches to value the SF-12. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of serious non-AIDS events among HIV-infected adults at Latin American sitesHIV MEDICINE, Issue 9 2010WH Belloso Objective Acquired immune deficiency appears to be associated with serious non-AIDS (SNA)-defining conditions such as cardiovascular disease, liver and renal insufficiency and non-AIDS-related malignancies. We analysed the incidence of, and factors associated with, several SNA events in the LATINA retrospective cohort. Materials and methods Cases of SNA events were recorded among cohort patients. Three controls were selected for each case from cohort members at risk. Conditional logistic models were fitted to estimate the effect of traditional risk factors as well as HIV-associated factors on non-AIDS-defining conditions. Results Among 6007 patients in follow-up, 130 had an SNA event (0.86 events/100 person-years of follow-up) and were defined as cases (40 with cardiovascular events, 54 with serious liver failure, 35 with non-AIDS-defining malignancies and two with renal insufficiency). Risk factors such as diabetes, hepatitis B and C virus coinfections and alcohol abuse showed an association with events, as expected. The last recorded CD4 T-cell count prior to index date (P=0.0056, with an average difference of more than 100 cells/,L) and area under the CD4 cell curve in the year previous to index date (P=0.0081) were significantly lower in cases than in controls. CD4 cell count at index date was significantly associated with the outcome after adjusting for risk factors. Conclusions The incidence and type of SNA events found in this Latin American cohort are similar to those reported in other regions. We found a significant association between immune deficiency and the risk of SNA events, even in patients under antiretroviral treatment. [source] Transient thermal modelling of heat recovery steam generators in combined cycle power plantsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 11 2007Sepehr Sanaye Abstract Heat recovery steam generator (HRSG) is a major component of a combined cycle power plant (CCPP). This equipment is particularly subject to severe thermal stress especially during cold start-up period. Hence, it is important to predict the operational parameters of HRSGs such as temperature of steam, water, hot gas and tube metal of heating elements as well as pressure change in drums during transient and steady-state operation. These parameters may be used for estimating thermal and mechanical stresses which are important in HRSG design and operation. In this paper, the results of a developed thermal model for predicting the working conditions of HRSG elements during transient and steady-state operations are reported. The model is capable of analysing arbitrary number of pressure levels and any number of elements such as superheater, evaporator, economizer, deaerator, desuperheater, reheater, as well as duct burners. To assess the correct performance of the developed model two kinds of data verification were performed. In the first kind of data verification, the program output was compared with the measured data collected from a cold start-up of an HRSG at Tehran CCPP. The variations of gas, water/steam and metal temperatures at various sections of HRSG, and pressure in drums were among the studied parameters. Mean differences of about 3.8% for temperature and about 9.2% for pressure were observed in this data comparison. In the second kind of data verification, the steady-state numerical output of the model was checked with the output of the well-known commercial software. An average difference of about 1.5% was found between the two latter groups of data. Copyright © 2007 John Wiley & Sons, Ltd. [source] Improved dynamic susceptibility contrast (DSC)-MR perfusion estimates by motion correctionJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2007Robert K. Kosior BSc Abstract Purpose To investigate the effect of patient motion on quantitative cerebral blood flow (CBF) maps in ischemic stroke patients and to evaluate the efficacy of a motion-correction scheme. Materials and Methods Perfusion data from 25 ischemic stroke patients were selected for analysis. Two motion profiles were applied to a digital anthropomorphic brain phantom to estimate accuracy. CBF images were generated for motion-corrupted and motion-corrected data. To correct for motion, rigid-body registration was performed. The realignment parameters and mean CBF in regions of interest were recorded. Results All patient data with motion exhibited visibly reduced intervolume misalignment after motion correction. Improved flow delineation between different tissues and a more clearly defined ischemic lesion (IL) were achieved in the motion-corrected CBF. A significant difference occurred in the IL (P < 0.05) for patients with severe motion with an average difference between corrupted and corrected data of 4.8 mL/minute/100 g. The phantom data supported the patient results with better CBF accuracy after motion correction and high registration accuracy (<1 mm translational and <1° rotational error). Conclusion Motion degrades flow differentiation between adjacent tissues in CBF maps and can cause ischemic severity to be underestimated. A registration motion correction scheme improves dynamic susceptibility contrast (DSC)-MR perfusion estimates. J. Magn. Reson. Imaging 2007;26:1167,1172. © 2007 Wiley-Liss, Inc. [source] Altered knee kinematics in ACL-deficient non-copers: A comparison using dynamic MRIJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2006Peter J. Barrance Abstract Kinematics measured during a short arc quadriceps knee extension exercise were compared in the knees of functionally unstable ACL-deficient patients, these patients' uninjured knees, and uninjured control subjects' knees. Cine phase contrast dynamic magnetic resonance imaging, in combination with a model-based tracking algorithm developed by the authors, was used to measure tibiofemoral kinematics as the subjects performed the active, supine posture knee extension exercise in the terminal 30 degrees of motion. Two determinants of tibiofemoral motion were measured: anterior/posterior location of the tibia relative to the femur, and axial rotation of the tibia relative to the femur. We hypothesized that more anterior tibial positioning, as well as differences in axial tibial rotation patterns, would be observed in ACL-deficient (ACL-D) knees when compared to uninjured knees. Multifactor ANOVA analyses were used to determine the dependence of the kinematic variables on (i) side (injured vs. uninjured, matched by subject in the control group), (ii) flexion angle measured at five-degree increments, and (iii) subject group (ACL-injured vs. control). Statistically significant anterior translation and external tibial rotation (screw home motion) accompanying knee extension were found. The ACL-D knees of the injured group exhibited significantly more anterior tibial positioning than the uninjured knees of these subjects (average difference over extension range,=,3.4,±,2.8 mm, p,<,0.01 at all angles compared), as well as the matched knees of the control subjects. There was a significant effect of interaction between side and subject group on A/P tibial position. We did not find significant differences in external tibial rotation associated with ACL deficiency. The changes to active joint kinematics documented in this entirely noninvasive study may contribute to cartilage degradation in ACL-D knees, and encourage more extensive investigations using similar methodology in the future. © 2005 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res [source] Ecological stress and linear enamel hypoplasia in CebusAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Madeleine B. Chollet Abstract Although it is assumed that monkeys in some environments experience more nutritional or physiological stress than others, little research has been conducted on this topic. This study examines the relationship between linear enamel hypoplasia (LEH) frequency, a physiological indicator of stress, and environmental stressors. To test this relationship, LEH frequencies were calculated for 144 Cebus from 54 locations in Brazil. Habitat, temperature range, and annual rainfall were compared between individuals with and without LEH. The LEH frequency for Cebus from semideciduous forests was significantly higher than that for monkeys from coastal areas, the rainforest, and the savanna (,2 = 9.97, df = 1; P = 0.0016). A significantly higher LEH frequency was also found for monkeys living in environments with the mean annual temperature between 15 and 18°C than for those in environments greater than 18°C (,2 = 7.74, df = 1, P = 0.0054). However, no significant difference was found between LEH frequency and annual rainfall (t = 1.22, P = 0.23) or the average difference in rainfall between the driest and wettest months (t = 0.77, P = 0.44). These results indicate that levels of physiological stress can differ among environments and that habitat and temperature, but not precipitation, may be driving the difference in stress levels among environments. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] A genome map of divergent artificial selection between Bos taurus dairy cattle and Bos taurus beef cattleANIMAL GENETICS, Issue 2 2009B. J. Hayes Summary A number of cattle breeds have become highly specialized for milk or beef production, following strong artificial selection for these traits. In this paper, we compare allele frequencies from 9323 single nucleotide polymorphism (SNP) markers genotyped in dairy and beef cattle breeds averaged in sliding windows across the genome, with the aim of identifying divergently selected regions of the genome between the production types. The value of the method for identifying selection signatures was validated by four sources of evidence. First, differences in allele frequencies between dairy and beef cattle at individual SNPs were correlated with the effects of those SNPs on production traits. Secondly, large differences in allele frequencies generally occurred in the same location for two independent data sets (correlation 0.45) between sliding window averages. Thirdly, the largest differences in sliding window average difference in allele frequencies were found on chromosome 20 in the region of the growth hormone receptor gene, which carries a mutation known to have an effect on milk production traits in a number of dairy populations. Finally, for the chromosome tested, the location of selection signatures between dairy and beef cattle was correlated with the location of selection signatures within dairy cattle. [source] Economic analysis of VenUS I, a randomized trial of two bandages for treating venous leg ulcersBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 10 2004C. P. Iglesias Background: The study investigated the cost-effectiveness of four-layer and short-stretch compression bandages for treating venous leg ulcers. Methods: Cost-effectiveness and cost-utility analyses were performed using patient-level data collected alongside the VenUS I leg ulcer study. The perspective for the economic analysis was that of the UK National Health Service (NHS) and Personal Social Service. The time horizon for the analysis was 1 year after recruitment. Health benefit was measured as differences in ulcer-free days and quality-adjusted life years (QALYs). Results: The mean healing time for ulcers treated with four-layer bandages was 10·9 (95 per cent confidence interval (c.i.) ,6·8 to 29·1) days less than that for ulcers treated with short-stretch bandages. Mean average difference in QALYs between compression systems was ,0·02 (95 per cent c.i. ,0·08 to 0·04). The four-layer bandage cost a mean of £227·32 (95 per cent c.i. £16·53 to £448 ·30) less per patient per year than the short-stretch bandage. Conclusion: On average, four-layer bandaging was associated with greater health benefits and lower costs than short-stretch bandaging. Copyright © 2004 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Beware the Dodo Bird: The Dangers of OvergeneralizationCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 1 2002Dianne L. Chambless Luborsky et al.'s conclusion that there are no meaningful differences in the efficacy of various psychothera-pies should be reconsidered for the following reasons: (a) errors in data analysis, (b) exclusion of research on many types of clients (e.g., children and adolescents), (c) faulty generalization to comparisons between therapies that have never been made, and (d) erroneous assumption that the average difference between all sorts of treatments for all sorts of problems can be assumed to represent the difference between any two types of treatment for a given problem. Concern for clients' welfare demands that psychologists be very wary of accepting the Dodo bird verdict. [source] A Comparison of Cost of Equity Estimates of Local and Global CAPMsFINANCIAL REVIEW, Issue 4 2001Dev R. Mishra G12/G15/G32 Abstract Cost of equity estimates are compared for three pricing models: the traditional local CAPM, the single (market) factor global CAPM, and the two-factor global CAPM, with both market and currency index factors. For 2989 US stocks, the average difference in the cost of equity estimates is about 48 basis points between the local CAPM and the single-factor global CAPM, and is about 61 basis points between the two global models. For 70 developed-market ADRs, the corresponding average differences are 76 and 47 basis points, respectively. For 48 emerging-market ADRs, the corresponding average differences are 57 and 70 basis points. [source] Medical demography and intergenerational inequalities in general practitioners' earningsHEALTH ECONOMICS, Issue 9 2008B. Dormont Abstract This article examines the link between restrictions on the number of physicians and general practitioners' (GPs) earnings. Using a representative panel of 6016 French self-employed GPs over the years 1983,2004, we estimate an earnings function to identify experience, time and cohort effects. The estimated gap in earnings between ,good' and ,bad' cohorts can be as large as 25%. GPs who began their practices during the eighties have the lowest permanent earnings: they belong to the large cohorts of the baby-boom and face the consequences of an unlimited number of places in medical schools. Conversely, the decrease in the number of places in medical schools led to an increase in permanent earnings of GPs who began their practices in the mid-nineties. A stochastic dominance analysis shows that unobserved heterogeneity does not compensate for average differences in earnings between cohorts. These findings suggest that the first years of practice are decisive for a GP. If competition between physicians is too intense at the beginning of their careers, they will suffer from permanently lower earnings. To conclude, our results show that the policies aimed at reducing the number of medical students succeeded in buoying up physicians' permanent earnings. Copyright © 2008 John Wiley & Sons, Ltd. [source] An analysis of the neighborhood impacts of a mortgage assistance program: A spatial hedonic modelJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 4 2010Wenhua Di Down payment or closing cost assistance is an effective program in addressing the wealth constraints of low-and moderate-income homebuyers. However, the spillover effect of such programs on the neighborhood is unknown. This paper estimates the impact of the City of Dallas Mortgage Assistance Program (MAP) on nearby home values using a hedonic model of home sales from 1990 to 2006. We define neighborhoods of 1,000 feet around each sale and estimate the average differences in sales prices between neighborhoods with various numbers of MAP properties before and after their appearance. We find that MAP properties tend to locate in neighborhoods with lower property values; however, unless a concentration of MAP properties forms, the infusion of MAP properties has little detrimental impact on neighboring property values. Moreover, low concentration of MAP properties has a modest positive impact on surrounding property values. © 2010 by the Association for Public Policy Analysis and Management. [source] Solar Ultraviolet-B Radiation in Urban Environments: The Case of Baltimore, Maryland,,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2004Gordon M. Heisler Ultraviolet-B radiation (UV-B, 280,320 nm) has important effects in urban areas, including those on human health. Broadband UV-B radiation is monitored in Baltimore, MD, as part of the Baltimore Ecosystem Study, a long-term ecological research program. We compare broadband UV-B irradiance in Baltimore with UV-B at two nearby locations: a more rural station 64 km southeast and a suburban station 42 km southwest. The monitoring station in Baltimore is on the roof of a 33-m-tall building; there are no significant obstructions to sky view. The U.S. Department of Agriculture UV-B Monitoring and Research Program provided all sensors, which were calibrated at the National Oceanic and Atmospheric Administration Central UV Calibration Facility. UV-B irradiances at the three sites generally were similar. Over all conditions, Baltimore and the suburban site measured 3.4% less irradiance than the rural site. This difference is within the anticipated ±3% calibration uncertainty of the pyranometers. On 59 days with cloud-free conditions at all three sites, average differences in measured UV-B among the three sites were even smaller; Baltimore measured 1.2% less irradiance than the rural site. High aerosol optical thickness strongly reduced daily UV-B dose, whereas [SO2] had no influence. Surface O3 increased with increasing UV-B dose when [NO2] exceeded 10 ppb. [source] Nei's gene diversity and the index of average differences are identical measures of diversity within populationsPLANT PATHOLOGY, Issue 5 2003E. Kosman It has been established that Nei's measure of the average genetic diversity per locus, HS, and the measure of average differences between isolates with respect to simple mismatch dissimilarity, are identical measures of diversity within populations. The Müller index of diversity can be considered as the correction of Nei's measure for small samples. [source] | |||||||||||||||||||