Home About us Contact
|
Home About us Contact | ||
|
|
||
Relative Differences (relative + difference)
Selected AbstractsTreatment of symptomatic diabetic polyneuropathy with the antioxidant ,-lipoic acid: a meta-analysisDIABETIC MEDICINE, Issue 2 2004D. Ziegler Abstract Aims To determine the efficacy and safety of 600 mg of ,-lipoic acid given intravenously over 3 weeks in diabetic patients with symptomatic polyneuropathy. Methods We searched the database of VIATRIS GmbH, Frankfurt, Germany, for clinical trials of ,-lipoic acid according to the following prerequisites: randomized, double-masked, placebo-controlled, parallel-group trial using ,-lipoic acid infusions of 600 mg i.v. per day for 3 weeks, except for weekends, in diabetic patients with positive sensory symptoms of polyneuropathy which were scored by the Total Symptom Score (TSS) in the feet on a daily basis. Four trials (ALADIN I, ALADIN III, SYDNEY, NATHAN II) comprised n = 1258 patients (,-lipoic acid n = 716; placebo n = 542) met these eligibility criteria and were included in a meta-analysis based on the intention-to-treat principle. Primary analysis involved a comparison of the differences in TSS from baseline to the end of i.v. Treatment between the groups treated with ,-lipoic acid or placebo. Secondary analyses included daily changes in TSS, responder rates (, 50% improvement in TSS), individual TSS components, Neuropathy Impairment Score (NIS), NIS of the lower limbs (NIS-LL), individual NIS-LL components, and the rates of adverse events. Results After 3 weeks the relative difference in favour of ,-lipoic acid vs. placebo was 24.1% (13.5, 33.4) (geometric mean with 95% confidence interval) for TSS and 16.0% (5.7, 25.2) for NIS-LL. The responder rates were 52.7% in patients treated with ,-lipoic acid and 36.9% in those on placebo (P < 0.05). On a daily basis there was a continuous increase in the magnitude of TSS improvement in favour of ,-lipoic acid vs. placebo which was noted first after 8 days of treatment. Among the individual components of the TSS, pain, burning, and numbness decreased in favour of ,-lipoic acid compared with placebo, while among the NIS-LL components pin-prick and touch-pressure sensation as well as ankle reflexes were improved in favour of ,-lipoic acid after 3 weeks. The rates of adverse events did not differ between the groups. Conclusions The results of this meta-analysis provide evidence that treatment with ,-lipoic acid (600 mg/day i.v.) over 3 weeks is safe and significantly improves both positive neuropathic symptoms and neuropathic deficits to a clinically meaningful degree in diabetic patients with symptomatic polyneuropathy. Diabet. Med. 21, 114,121 (2004) [source] Estimation of rate ratio and relative difference in matched-pairs under inverse samplingENVIRONMETRICS, Issue 6 2001Kung-Jong Lui Abstract To increase the efficiency of a study and to eliminate the effects of some nuisance confounders, we may consider employing a matched-pair design. Under the commonly assumed quadrinomial sampling, in which the total number of matched-pairs is fixed, we note that the maximum likelihood estimator (MLE) of rate ratio (RR) has an infinitely large bias and no finite variance, and so does the MLE of relative difference (RD). To avoid this theoretical concern, this paper suggests use of an inverse sampling and notes that the MLEs of these parameters, which are actually of the same forms as those under the quadrinomial sampling, are also the uniformly minimum variance estimators (UMVUEs) under the proposed samplings. This paper further derives the exact variances of these MLEs and the corresponding UMVUEs of these variances. Finally, this paper includes a discussion on interval estimation of the RR and RD using these results as well. Copyright © 2001 John Wiley & Sons, Ltd. [source] Depth of detection of highly conducting and volume polarizable targets using induced polarizationGEOPHYSICAL PROSPECTING, Issue 5 2000A. Apparao We define the apparent frequency effect in induced polarization (IP) as the relative difference between apparent resistivities measured using DC excitation on the one hand and high-frequency excitation (when the IP effect vanishes) on the other. Assuming a given threshold for the minimum detectable anomaly in the apparent frequency effect, the depth of detection of a target by IP can be defined as that depth below which the target response is lower than the threshold for a given electrode array. Physical modelling shows that for the various arrays, the depth of detection of a highly conducting and volume polarizable target agrees closely with the depth of detection of an infinitely conducting and non-polarized body of the same shape and size. The greatest depth of detection is obtained with a two-electrode array, followed by a three-electrode array, while the smallest depth of detection is obtained with a Wenner array when the array spread is in-line (i.e. perpendicular to the strike direction). The depth of detection with a Wenner array improves considerably and is almost equal to that of a two-electrode array when the array spread is broadside (i.e. along the strike direction). [source] Power function decay of hydraulic conductivity for a TOPMODEL-based infiltration routineHYDROLOGICAL PROCESSES, Issue 18 2006Jun Wang Abstract TOPMODEL rainfall-runoff hydrologic concepts are based on soil saturation processes, where soil controls on hydrograph recession have been represented by linear, exponential, and power function decay with soil depth. Although these decay formulations have been incorporated into baseflow decay and topographic index computations, only the linear and exponential forms have been incorporated into infiltration subroutines. This study develops a power function formulation of the Green and Ampt infiltration equation for the case where the power n = 1 and 2. This new function was created to represent field measurements in the New York City, USA, Ward Pound Ridge drinking water supply area, and provide support for similar sites reported by other researchers. Derivation of the power-function-based Green and Ampt model begins with the Green and Ampt formulation used by Beven in deriving an exponential decay model. Differences between the linear, exponential, and power function infiltration scenarios are sensitive to the relative difference between rainfall rates and hydraulic conductivity. Using a low-frequency 30 min design storm with 4·8 cm h,1 rain, the n = 2 power function formulation allows for a faster decay of infiltration and more rapid generation of runoff. Infiltration excess runoff is rare in most forested watersheds, and advantages of the power function infiltration routine may primarily include replication of field-observed processes in urbanized areas and numerical consistency with power function decay of baseflow and topographic index distributions. Equation development is presented within a TOPMODEL-based Ward Pound Ridge rainfall-runoff simulation. Copyright © 2006 John Wiley & Sons, Ltd. [source] Temporal Coherence of Chlorophyll a during a Spring Phytoplankton Bloom in Xiangxi Bay of Three-Gorges Reservoir, ChinaINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 6 2009Yao-Yang Xu Abstract Algal bloom phenomenon was defined as "the rapid growth of one or more phytoplankton species which leads to a rapid increase in the biomass of phytoplankton", yet most estimates of temporal coherence are based on yearly or monthly sampling frequencies and little is known of how synchrony varies among phytoplankton or of the causes of temporal coherence during spring algal bloom. In this study, data of chlorophyll a and related environmental parameters were weekly gathered at 15 sampling sites in Xiangxi Bay of Three-Gorges Reservoir (TGR, China) to evaluate patterns of temporal coherence for phytoplankton during spring bloom and test if spatial heterogeneity of nutrient and inorganic suspended particles within a single ecosystem influences synchrony of spring phytoplankton dynamics. There is a clear spatial and temporal variation in chlorophyll a across Xiangxi Bay. The degree of temporal coherence for chlorophyll a between pairs of sites located in Xiangxi Bay ranged from ,0.367 to 0.952 with mean and median values of 0.349 and 0.321, respectively. Low levels of temporal coherence were often detected among the three stretches of the bay (Down reach, middle reach and upper reach), while high levels of temporal coherence were often found within the same reach of the bay. The relative difference of DIN between pair sites was the strong predictor of temporal coherence for chlorophyll a in down and middle reach of the bay, while the relative difference in Anorganic Suspended Solids was the important factor regulating temporal coherence in middle and upper reach. Contrary to many studies, these results illustrate that, in a small geographic area (a single reservoir bay of approximately 25 km), spatial heterogeneity influence synchrony of phytoplankton dynamics during spring bloom and local processes may override the effects of regional processes or dispersal. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Adolescent C57BL/6J (but not DBA/2J) Mice Consume Greater Amounts of Limited-Access Ethanol Compared to Adults and Display Continued Elevated Ethanol Intake into AdulthoodALCOHOLISM, Issue 4 2010Eileen M. Moore Background:, Alcohol use is common during the adolescent period, a time at which a number of crucial neurobiological, hormonal, and behavioral changes occur (Spear, 2000). In order to more fully understand the complex interaction between alcohol use and these age-typical neurobiological changes, animal models must be utilized. Rodents experience a developmental period similar to that of adolescence. Although rat models have shown striking adolescent-specific differences in sensitivity to ethanol, little work has been done in mice despite the fact that the C57BL/6J (B6) and DBA2/J (D2) mice have been shown to markedly differ in ethanol preference drinking and exhibit widely different sensitivities to ethanol. Methods:, The current study examined ethanol intake in adolescent and adult B6 and D2 mice using a limited access alcohol exposure paradigm called Drinking in the Dark (DID). Additionally, the effect of adolescent (or adult) ethanol exposure on subsequent adult ethanol intake was examined by re-exposing the mice to the same paradigm once the adolescents reached adulthood. We hypothesized that adolescent (P25,45) mice would exhibit greater binge-like alcohol intake compared to adults (P60,80), and that B6 mice would exhibit greater binge-like alcohol intake compared to D2 mice. Moreover, we predicted that relative difference in binge-like alcohol intake between adolescents and adults would be greater in D2 mice. Results:, Adolescent B6 mice consumed more ethanol than adults in the DID model. There was no difference between adolescent and adult D2 mice. Conclusions:, This work adds to the literature suggesting that adolescents will consume more ethanol than adults and that this exposure can result in altered adult intake. However, this effect seems largely dependent upon genotype. Future work will continue to examine age-related differences in ethanol intake, preference, and sensitivity in inbred mouse strains. [source] Omeprazole-Mg 20.6 mg is superior to lansoprazole 15 mg for control of gastric acid: a comparison of over-the-counter doses of proton pump inhibitorsALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 8 2010P. B. MINER JR Aliment Pharmacol Ther,31, 846,851 Summary Background, Over-the-counter (OTC) proton pump inhibitors (PPIs) relieve heartburn by decreasing the production of gastric acid, but may not do so with equal effectiveness. It is important for healthcare professionals to compare the ability of OTC PPIs to control gastric acid when recommending them for patients with frequent heartburn. Aim, To compare the effects of omeprazole-Mg 20.6 mg and lansoprazole 15 mg (OTC doses in the US) on 24-h steady state gastric acid suppression. Methods, This single-centre, randomized, double-blind clinical study compared the steady-state gastric acid control of omeprazole-Mg 20.6 mg vs. lansoprazole 15 mg, dosed before breakfast. Volunteers were enrolled in a 3-period, cross-over design (ABB, BAA) with 24-h gastric pH monitoring on dosing day 5. The primary efficacy variable was the percentage time intragastric pH was >4.0 over 24 h on day 5 of dosing. Results, Forty subjects were enrolled; all completed the study. The mean (SE) percentage time pH was >4.0 was 45.7% (3.45%) for omeprazole-Mg 20.6 mg and 36.8% (3.45%) for lansoprazole 15 mg, an absolute difference of 8.9% (P < 0.0001), and a relative difference of 24.2%. Both drugs were well tolerated. Conclusion, Omeprazole-Mg 20.6 mg provided a statistically significantly (P < 0.0001) greater acid control than lansoprazole 15 mg. [source] Noninvasive blood flow imaging for real-time feedback during laser therapy of port wine stain birthmarksLASERS IN SURGERY AND MEDICINE, Issue 3 2008Yu-Chih Huang MS Abstract Background and Objectives During laser therapy of port wine stain (PWS) birthmarks, regions of persistent perfusion may exist. Immediate retreatment of such regions may improve PWS laser therapeutic outcome. To address this need, we propose use of laser speckle imaging (LSI) to provide real-time, quantitative feedback during laser surgery. Herein, we present in vitro and in vivo data collected with a clinic-based LSI instrument. Study Design/Materials and Methods Prior to clinical implementation, we first investigated three aspects of LSI deemed important for clinical imaging: (1) instrument depth of field (DOF); (2) effects of laser irradiance on speckle flow index (SFI) values; and (3) measurement repeatability. Clinical measurements were acquired from the lesions of PWS patients immediately prior to and after laser therapy at the Beckman Laser Institute. Results Our preclinical data suggest the following: (1) instrument DOF was ,1 cm; (2) quantitative flow characterization with LSI was practically unaffected at normalized irradiance values between 0.06 and 0.5; and (3) our LSI instrument was capable of highly reproducible SFI values. From our clinical measurements, we found that the relative difference between blood perfusion in PWS lesions and adjacent normal skin was highly variable. Based on SFI images, the perfusion of PWS skin is sometimes indistinguishable from that of adjacent normal skin. With laser therapy, we measured a global decrease in blood perfusion, and we frequently observed distinct regions of persistent perfusion. Conclusions Our results demonstrate the potential role of image-guided laser therapy of PWS birthmarks. LSI is a promising tool for noninvasive blood flow characterization during laser therapy due to its relative simplicity and low cost. Laser Surg. Med. 40:167,173, 2008. © 2008 Wiley-Liss, Inc. [source] Sustained effect of SQ-standardized grass allergy immunotherapy tablet on rhinoconjunctivitis quality of lifeALLERGY, Issue 6 2010L. Frølund To cite this article: Frølund L, Durham SR, Calderon M, Emminger W, Andersen JS, Rask P, Dahl R. Sustained effect of SQ-standardized grass allergy immunotherapy tablet on rhinoconjunctivitis quality of life. Allergy 2010; 65: 753,757. Abstract Background:, The prevalence of allergic rhinoconjunctivitis has increased significantly over the past decades with grass pollen being a common trigger. The impact of allergy on patient's quality of life is substantial. Aim:, To investigate the sustained effect on quality of life during the grass pollen season 1 year after 3 years of treatment with the SQ-standardized grass allergy immunotherapy tablet (AIT), Grazax® (Phleum pratense 75,000 SQ-T/2800 BAU; ALK, Denmark). Methods:, The trial was a randomized, parallel-group, double-blind, placebo-controlled trial in adult subjects with a history of moderate-severe grass pollen induced rhinoconjunctivitis inadequately controlled by symptomatic medications. Subjects received 3 years of grass AIT (n = 157) or placebo (n = 126), followed by 1 year of follow-up. Quality of life assessments were based on the standardized rhinoconjunctivitis quality of life questionnaire (RQLQ(S)); completed weekly during the entire grass pollen season. Results:, During follow-up, the overall RQLQ(S) score for the entire grass pollen season was significantly improved in the active group (relative difference to placebo: 23%, P = 0.004). The improvement was higher during the peak pollen season (28%, P = 0.001). The treatment effect of grass AIT during the follow-up year and the previous three treatment years was similar. Improvements were found in all seven RQLQ(S) domains. The RQLQ(S) as a function of the weekly average pollen counts showed a clear separation between the treatment groups (P < 0.001). Conclusion:, In subjects inadequately controlled by symptomatic medications, grass AIT provided sustained and clinically relevant improvements in rhinoconjunctivitis quality of life compared to placebo. The effect increased with increasing grass pollen exposure. [source] Use of the GlucoWatch® biographer in children and adolescents with diabetesPEDIATRIC DIABETES, Issue 3 2002Richard C. Eastman Abstract: Objective:, This study was done to evaluate the accuracy and safety of measuring glucose with the GlucoWatch® biographer in children and adolescents with diabetes. Methods:, Accuracy was assessed by comparing biographer glucose measurements with hourly blood glucose measurements using the HemoCue (Aktiebolaget Leo, Helsingborg, Sweden) Photometer for up to 12 h of monitoring. Safety was evaluated by examining the biographer application sites immediately upon removal of the devices, and then at regular intervals. Results: Sixty-six subjects each wore three biographers at sites including the forearm, upper arm, leg, and torso. For forearm biographers, the mean absolute relative difference between biographer readings and blood glucose was 21%. Ninety-five per cent of biographer readings fell into the A or B regions of the Clarke error grid, and 97.3% into the A or B regions of the consensus error grid. Data from biographers worn at the alternative sites were similar to data from the forearm biographers. Two strong reactions to the adhesive pad of the biographer AutoSensor were observed. Most skin reactions were mild. Conclusions:, The GlucoWatch biographer is well tolerated by children and adolescents with diabetes. Performance is similar when the device is worn at different anatomical sites, and is similar to the performance on the forearm, previously reported in adults. [source] Effects of climate on occurrence and size of large fires in a northern hardwood landscape: historical trends, forecasts, and implications for climate change in Témiscamingue, QuébecAPPLIED VEGETATION SCIENCE, Issue 3 2009C. Ronnie Drever Abstract Questions: What climate variables best explain fire occurrence and area burned in the Great Lakes-St Lawrence forest of Canada? How will climate change influence these climate variables and thereby affect the occurrence of fire and area burned in a deciduous forest landscape in Témiscamingue, Québec, Canada? Location: West central Québec and the Great Lakes-St Lawrence forest of Canada. Methods: We first used an information-theoretic framework to evaluate the relative role of different weather variables in explaining occurrence and area burned of large fires (>200 ha, 1959-1999) across the Great Lakes-St Lawrence forest region. Second, we examined how these weather variables varied historically in Témiscamingue and, third, how they may change between the present and 2100 according to different scenarios of climate change based on two Global Circulation Models. Results: Mean monthly temperature maxima during the fire season (Apr-Oct) and weighted sequences of dry spells best explained fire occurrence and area burned. Between 1910 and 2004, mean monthly temperature maxima in Témiscamingue showed no apparent temporal trend, while dry spell sequences decreased in frequency and length. All future scenarios show an increase in mean monthly temperature maxima, and one model scenario forecasts an increase in dry spell sequences, resulting in a slight increase in forecasted annual area burned. Conclusion: Despite the forecasted increase in fire activity, effects of climate change on fire will not likely affect forest structure and composition as much as natural succession or harvesting and other disturbances, principally because of the large relative difference in area affected by these processes. [source] Cooperative activity of multiple upper layer proteins for thalamocortical axon growthDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2008Takuro Maruyama Abstract During development, sensory thalamocortical (TC) axons grow into the neocortex and terminate primarily in layer 4. To study the molecular mechanism that underlies lamina-specific TC axon termination, we investigated the responsiveness of TC axons to ephrin-A5, semaphorin-7A (Sema7A) and kit ligand (KL), which are expressed in the upper layers of the developing cortex. Dissociated cells of the dorsal thalamus from embryonic rat brain were cultured on dishes that were coated with preclustered Fc-tagged extracellular domains of these molecules. Each protein was found to promote TC axon growth in a dose-dependent fashion of a bell-shaped curve. Any combination of the three proteins showed a cooperative effect in lower concentrations but not in higher concentrations, suggesting that their growth-promoting activities act in a common pathway. The effect of spatial distributions of these proteins was further tested on a filter membrane, in which these proteins were printed at a size that recapitulates the scale of laminar thickness in vivo, using a novel protein-printing technique, Simple-To-mAke Micropore Protein-Printing (STAMP2) method. The results demonstrated that TC axons grew massively on the laminin-coated region but were prevented from invading the adjacent ephrin-A5-printed region, suggesting that TC axons detect relative differences in the growth effect between these regions. Moreover, the inhibitory action of ephrin-A5 was enhanced by copresence with KL and Sema7A. Together, these results suggest that the lamina-specific TC axon targeting mechanism involves growth-inhibitory activity by multiple molecules in the upper layers and detection in the molecular environments between the upper and deep layers. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2008 [source] Assessment of different techniques for subcutaneous glucose monitoring in Type 1 diabetic patients during ,real-life' glucose excursionsDIABETIC MEDICINE, Issue 3 2010J. K. Mader Diabet. Med. 27, 332,338 (2010) Abstract Aims, To compare the accuracy of two marketed subcutaneous glucose monitoring devices (Guardian RT, GRT; GlucoDay S, GDS) and standard microdialysis (CMA60; MD) in Type 1 diabetic patients. Methods, Seven male Type diabetic patients were investigated over a period of 26 h simulating real-life meal glucose excursions. Catheters of the three systems were inserted into subcutaneous adipose tissue of the abdominal region. For MD, interstitial fluid was sampled at 30- to 60-min intervals for offline glucose determination. Reference samples were taken at 15- to 60-min intervals. All three systems were prospectively calibrated to reference. Median differences, median absolute relative differences (MARD), median absolute differences (MAD), Bland,Altman plot and Clark Error Grid were used to determine accuracy. Results, Bland,Altman analysis indicated a mean glucose difference (2 standard deviations) between reference and interstitial glucose of ,10.5 (41.8) % for GRT, 20.2 (55.9) % for GDS and 6.5 (35.2) % for MD, respectively. Overall MAD (interquartile range) was 1.07 (0.39; 2.04) mmol/l for GRT, 1.59 (0.54; 3.08) mmol/l for GDS and 0.76 (0.26; 1.58) mmol/l for MD. Overall MARD was 15.0 (5.6; 23.4) % (GRT), 19.7 (6.1; 37.6) % (GDS) and 8.7 (4.1; 18.3) % (MD), respectively. Total sensor failure occurred in two subjects using GRT and one subject using GDS. Conclusions, The three investigated technologies had comparable performance. Whereas GRT underestimated actual blood glucose, GDS and MD overestimated blood glucose. Considerable deviations during daily life meal glucose excursions from reference glucose were observed for all three investigated technologies. Present technologies may require further improvement until individual data can lead to direct and automated generation of therapeutic advice in diabetes management. [source] Modelling the concentrations of nitrogen and water-soluble carbohydrates in grass herbage ingested by cattle under strip-grazing managementGRASS & FORAGE SCIENCE, Issue 1 2008N. J. Hoekstra Abstract There is scope of increasing the nitrogen (N) efficiency of grazing cattle through manipulation of the energy and N concentrations in the herbage ingested. Because of asymmetric grazing by cattle between individual plant parts, it has not yet been established how this translates into the concentrations of N and water-soluble carbohydrates (WSC) in the herbage ingested. A model is described with the objective of assessing the efficacy of individual tools in grassland management in manipulating the WSC and N concentrations of the herbage ingested by cattle under strip-grazing management throughout the growing season. The model was calibrated and independently evaluated for early (April), mid- (June, regrowth phase) and late (September) parts of the growing season. There was a high correlation between predicted and observed WSC concentrations in the ingested herbage (R2 = 0·78, P < 0·001). The correlation between predicted and observed neutral-detergent fibre (NDF) concentrations in the ingested herbage was lower (R2 = 0·49, P < 0·05) with a small absolute bias. Differences in the N concentration between laminae and sheaths, and between clean patches and fouled patches, were adequately simulated and it was concluded that the model could be used to assess the efficacy of grassland management tools for manipulating the WSC and N concentrations in the ingested herbage. Model application showed that reduced rates of application of N fertilizer and longer rotation lengths were effective tools for manipulating herbage quality in early and mid-season. During the later part of the growing season, the large proportion of area affected by dung and urine reduced the effect of application rate of N fertilizer on herbage quality. In contrast, relative differences between high-sugar and low-sugar cultivars of perennial ryegrass were largest during this period. This suggests that high-sugar cultivars may be an important tool in increasing N efficiency by cattle when risks of N losses to water bodies are largest. The model output showed that defoliation height affects the chemical composition of the ingested herbage of both the current and the subsequent grazing period. [source] Pilot study comparing patients' valuation of health-care services with Medicare's relative value unitsHEALTH EXPECTATIONS, Issue 4 2008Steven J. Kravet MD Abstract Background and aims, Physician reimbursement for services and thus income are largely determined by the Medicare Resource-Based Relative Value Scale. Patients' assessment of the value of physician services has never been considered in the calculation. This study sought to compare patients' valuation of health-care services to Medicare's relative value unit (RVU) assessments and to discover patients' perceptions about the relative differences in incomes across physician specialties. Design, Cross-sectional survey. Participants and setting, Individuals in select outpatient waiting areas at Johns Hopkins Bayview Medical Center. Methods, Data collection included the use of a visual analog ,value scale' wherein participants assigned value to 10 specific physician-dependent health-care services. Informants were also asked to estimate the annualized incomes of physicians in specialties related to the abovementioned services. Comparisons of (i) the ,patient valuation RVUs' with actual Medicare RVUs, and (ii) patients' estimations of physician income with actual income were explored using t -tests. Outcomes, Of the 206 eligible individuals, 186 (90%) agreed to participate. Participants assigned a significantly higher mean value to 7 of the 10 services compared with Medicare RVUs (P < 0.001) and the range in values assigned by participants was much smaller than Medicare's (a factor of 2 vs. 22). With the exception of primary care, respondents estimated that physicians earn significantly less than their actual income (all P < 0.001) and the differential across specialties was thought to be much smaller (estimate: $88 225, actual: $146 769). Conclusion, In this pilot study, patients' estimations of the value health-care services were markedly different from the Medicare RVU system. Mechanisms for incorporating patients' valuation of services rendered by physicians may be warranted. [source] Online pressure,volume,temperature measurements of polypropylene using a testing mold to simulate the injection-molding processJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2010Jian Wang Abstract To obtain accurate prediction of service performance and service life of polymers and to optimize the processing parameters, a modified online measurement was used to measure the pressure,volume,temperature (PVT) properties of polymers under certain processing conditions. The measurement was based on an injection molding machine, and it was used to obtain the PVT data of polymers directly with a special testing mold under normal processing conditions. The PVT properties of a semicrystalline polymer, polypropylene, were measured through both an online testing mold and a conventional piston,die dilatometer. The PVT properties were correlated by a modified two-domain Tait equation of state. The differences between the two groups of PVT data measured were investigated, and relative differences, especially in the rubbery state because of different cooling or heating measuring modes and sample forms, were observed. Numerical simulations of injection-molding processes were carried out by Moldflow software with both of the types of PVT data. The resulting online PVT data exhibited improvement in the accurate prediction of shrinkage and warpage. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] CONSIDERING THE SOURCE: DOES THE COUNTRY OF ORIGIN OF FDI MATTER TO ECONOMIC GROWTH?,JOURNAL OF REGIONAL SCIENCE, Issue 2 2008Timothy C. Ford ABSTRACT It has long been surmised that firms controlled by different countries may have unequal effects on the host economies in which they locate. By looking at the seven major source countries of foreign direct investment (FDI) in the United States, we provide empirical evidence that the state growth effects of FDI differ by source country. We attribute these differential growth effects to the relative differences in factor endowments between the source country and the state. The implication of this result is that technology transfer, believed to be the engine of economic growth, becomes more costly the more dissimilar the endowments. [source] Differences in Entrepreneurial Opportunities: The Role of Tacitness and Codification in Opportunity Identification,JOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 1 2009Brett R. Smith The role of opportunities in the entrepreneurial process remains relatively underdeveloped. To address this issue, we develop a definition of an entrepreneurial opportunity and draw upon a distinction from the domain of knowledge management to suggest a continuum of entrepreneurial opportunities ranging from codified to tacit. Though both traditional and contemporary research has examined how individual differences relate to the identification of opportunities, we focus instead on the importance of differences in the opportunities themselves. Specifically, we examine how relative differences in the degree of opportunity tacitness relate to the process of opportunity identification. We find that relatively more codified opportunities are more likely to be discovered through systematic search, whereas more tacit opportunities are more likely to be identified due to prior experience. These findings contribute to an increased understanding of the role of the opportunity in entrepreneurship research and have important implications for economic theories of entrepreneurship, entrepreneurial learning, entrepreneurial networks, and entrepreneurial education. [source] Structure determination of slowly exchanging conformers in solution using high-resolution NMR, computational modeling and DFT-GIAO chemical shielding: application to an erythronolide A derivativeMAGNETIC RESONANCE IN CHEMISTRY, Issue 11 2009Dieter Muri Abstract We discuss and demonstrate the potential of HSQC-TOCSY and HSQC-NOESY experiments to offer solutions for overlap problems in COSY and NOESY spectra, leading to improved signals that can be unambiguously assigned to individual carbons. Direct comparison of experimental 1H and 13C chemical shielding with density functional theory (DFT)-calculated values are uninformative; in contrast, the relative differences in experimental shielding between pairs of molecules correlates well with the relative differences in DFT-GIAO shielding for the computed lowest energy conformers. A detailed application of both experimental and theoretical techniques is illustrated for slowly exchanging conformers of an erythronolide A derivative, which demonstrates that structure determination can strongly benefit from the interplay between experiment and theory. Copyright © 2009 John Wiley & Sons, Ltd. [source] Compartmental relaxation and diffusion tensor imaging measurements in vivo in ,-carrageenan-induced edema in rat skeletal muscle,NMR IN BIOMEDICINE, Issue 6 2008Reuben H. Fan Abstract Integrated diffusion tensor T2 measurements were made on normal and edematous rat muscle, and the data were fitted with one- and two-compartment models, respectively. Edematous muscle exhibited a short-lived component (T2,=,28,±,6,ms), with diffusion characteristics similar to that of normal muscle, and a long-lived component (T2,=,96,±,27,ms), with greater mean apparent diffusion coefficient (ADC) and lower fractional anisotropy (FA). With this two-component description of diffusion and relaxation, values of ADC and FA estimated with a conventional pulsed-gradient spin-echo sequence will depend on the echo time, relative fraction of short-lived and long-lived water signals, and the intrinsic ADC and FA values within the tissue. On the basis of the relative differences in water diffusion properties between long-lived and short-lived water signals, as well as the similarities between the short-lived component and normal tissue, it is postulated that these two signal components largely reflect intracellular and extracellular water. Copyright © 2007 John Wiley & Sons, Ltd. [source] Swedish pre-school children's UVR exposure , a comparison between two outdoor environmentsPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 1 2004C. Boldeman Background: Overexposure to ultraviolet radiation (UVR) in childhood is a major risk factor for skin cancer. Shady environments are recommended as one method of protection. Methods: Environmental exposure to UVR and environmental protection were assessed by dosimeter measurements on 64 children aged 1,6 years at two geographically close and topographically similar pre-schools outside Stockholm. Outdoor play constructions of site 1 (34 children) were mainly exposed to the sun, and those of site 2 (30 children) were mainly shaded. Dosimetry was carried out during 11 work days in May,June 2002 under clear weather conditions. The reliability of dosimeters was tested with meteorologically modelled data from SMHI, and with stationary dosimeters exposed to free sky, and compared with other UV instruments. The differences between children's outdoor stays were adjusted for. Results: The children's average daily exposures were approximately 200 JCIE/m2 erythemally effective UVR. The average relative UVR exposure (% total available UVR 08:30,18:30) was 6.4% (7.0% at site 1, 5.7% at site 2). Fractions of available UVR during outdoor stay were 14.4% (both sites), 15.3% (site 1), and 13.3% (site 2). In terms of relative differences, 5,6-year-old children at site 2 were exposed to 41% less UVR, and 1,4-year-old children 6% less than those at site 1. Conclusion: The difference can be explained by the children's outdoor pre-school environments, and the behaviors linked to these environments. It is recommended to consider the attractiveness of shady environments in the design of children's pre-school playgrounds, particularly if these are extremely exposed to the sun. [source] Social inequality in premature mortality among polish urban adults during economic transitionAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 6 2007Halina Ko, odziej Rates of premature mortality among adults are important measures of the economic and psychosocial well-being of human populations. In many countries, such rates are, as a rule, inversely related to the level of attained education. We examined changes in educational group-specific mortality rates among urban adults in Poland during the country's rapid transition in the 1990s from a socialist command economy to a free market system. Two census-based analyses of individual death records of urban dwellers aged 35,64 years were compared. We utilized all records of death, which occurred during the 2-year periods 1988,89 and 2001,02. Population denominators were taken from the censuses of 1988 and 2002. The age-specific mortality rates were used to evaluate absolute differences in mortality. To assess relative differences between educational levels, mortality rate ratios (MRRs) with 95% CI (confidence interval) were calculated using Poisson regression. A regular educational gradient in mortality persisted in each 10-year age group throughout the period covered by our data. Moreover, age-specific mortality rates declined steadily in all educational groups, and this decline was most marked in the two oldest age groups (45,54 and 55,64 years). The trend was accompanied by widening of educational differences in mortality as expressed by MRRs. Systemic political transformation in Poland has brought a mixture of beneficial and detrimental effects on the well-being of society. With regard to the changes in rates of premature mortality among adults, the benefits have prevailed, although individuals with the lowest educational level benefited less than those with the highest education. Am. J. Hum. Biol., 2007. © 2007 Wiley-Liss, Inc. [source] A Welfare Loss Measure of Unemployment with An Empirical IllustrationTHE MANCHESTER SCHOOL, Issue 2 2001Satya Paul Based on interpersonal comparisons, a welfare loss measure of unemployment is developed. The proposed measure is additively decomposable which enables us to assess the group-specific contribution to aggregate welfare cost. It possesses certain other desirable properties. It is sensitive to unemployment rate, mean duration of unemployment and the relative differences in the duration of unemployment. Since all these can vary differently over the years and across regions, the proposed measure is most suitable for comparing the welfare cost of unemployment over a period of time or across regions. An empirical exercise based on the Australian labour force survey data illustrates the usefulness and an easy applicability of the proposed measure. [source] Radiofrequency exposure on fast patrol boats in the Royal Norwegian Navy,an approach to a dose assessmentBIOELECTROMAGNETICS, Issue 5 2010Valborg Baste Abstract Epidemiological studies related to radiofrequency (RF) electromagnetic fields (EMF) have mainly used crude proxies for exposure, such as job titles, distance to, or use of different equipment emitting RF EMF. The Royal Norwegian Navy (RNoN) has measured RF field emitted from high-frequency antennas and radars on several spots where the crew would most likely be located aboard fast patrol boats (FPB). These boats are small, with short distance between the crew and the equipment emitting RF field. We have described the measured RF exposure aboard FPB and suggested different methods for calculations of total exposure and annual dose. Linear and spatial average in addition to percentage of ICNIRP and squared deviation of ICNIRP has been used. The methods will form the basis of a job exposure matrix where relative differences in exposure between groups of crew members can be used in further epidemiological studies of reproductive health. Bioelectromagnetics 31:350,360, 2010. © 2010 Wiley-Liss, Inc. [source] Molecular chemical structure of barley proteins revealed by ultra-spatially resolved synchrotron light sourced FTIR microspectroscopy: Comparison of barley varietiesBIOPOLYMERS, Issue 4 2007Peiqiang Yu Abstract Barley protein structure affects the barley quality, fermentation, and degradation behavior in both humans and animals among other factors such as protein matrix. Publications show various biological differences among barley varieties such as Valier and Harrington, which have significantly different degradation behaviors. The objectives of this study were to reveal the molecular structure of barley protein, comparing various varieties (Dolly, Valier, Harrington, LP955, AC Metcalfe, and Sisler), and quantify protein structure profiles using Gaussian and Lorentzian methods of multi-component peak modeling by using the ultra-spatially resolved synchrotron light sourced Fourier transform infrared microspectroscopy (SFTIRM). The items of the protein molecular structure revealed included protein structure ,-helices, ,-sheets, and others such as ,-turns and random coils. The experiment was performed at the National Synchrotron Light Source in Brookhaven National Laboratory (BNL, US Department of Energy, NY). The results showed that with the SFTIRM, the molecular structure of barley protein could be revealed. Barley protein structures exhibited significant differences among the varieties in terms of proportion and ratio of model-fitted ,-helices, ,-sheets, and others. By using multi-component peaks modeling at protein amide I region of 1710,1576 cm,1, the results show that barley protein consisted of approximately 18,34% of ,-helices, 14,25% of ,-sheets, and 44,69% others. AC Metcalfe, Sisler, and LP955 consisted of higher (P < 0.05) proportions of ,-helices (30,34%) than Dolly and Valier (,-helices 18,23%). Harrington was in between which was 25%. For protein ,-sheets, AC Metcalfe, and LP955 consisted of higher proportions (22,25%) than Dolly and Valier (13,17%). Different barley varieties contained different ,-helix to ,-sheet ratios, ranging from 1.4 to 2.0, although the difference were insignificant (P > 0.05). The ratio of ,-helices to others (0.3 to 1.0, P < 0.05) and that of ,-sheets to others (0.2 to 0.8, P < 0.05) were different among the barley varieties. It needs to be pointed out that using a multi-peak modeling for protein structure analysis is only for making relative estimates and not exact determinations and only for the comparison purpose between varieties. The principal component analysis showed that protein amide I Fourier self-deconvolution spectra were different among the barley varieties, indicating that protein internal molecular structure differed. The above results demonstrate the potential of the SFTIRM to localize relatively pure protein areas in barley tissues and reveal protein molecular structure. The results indicated relative differences in protein structures among the barley varieties, which may partly explain the biological differences among the barley varieties. Further study is needed to understand the relationship between barley molecular chemical structure and biological features in terms of nutrient availability and digestive behavior. © 2006 Wiley Periodicals, Inc. Biopolymers 85:308,317, 2007. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] An unrandomized prospective comparison of urinary continence, bowel symptoms and the need for further procedures in patients with and with no adjuvant radiation after radical prostatectomyBJU INTERNATIONAL, Issue 4 2003T. Hofmann OBJECTIVE To prospectively assess, using a questionnaire-based study, the relative differences and changes in urinary continence and bowel symptoms, and the need for further surgery, within the first year after radical retropubic prostatectomy (RRP) in patients with and with no adjuvant radiotherapy (aRT). PATIENTS AND METHODS The study included 96 men with clinically organ-confined adenocarcinoma of the prostate who underwent RRP between March 1998 and June 1999. A subset of 36 patients was recommended aRT of the prostatic fossa (median dose 54 Gy) because of positive surgical margins and/or seminal vesicle involvement. Using a mailed questionnaire all patients were prospectively assessed at 4-month intervals for the first year after RRP. RESULTS Valid data were analysed from 83 patients (overall response rate 86%), of whom 30 (36%) had received aRT. At 4 months a significantly lower proportion used no pads and significantly more used 1 pad/day in the aRT than in the RRP group (both P < 0.05). Eight and 12 months after RRP there was no statistically significant difference between the groups in urinary incontinence. However, 53% of men in the aRT group had stool urgency and 13% reported fecal incontinence at 4 months, compared with 1.9% and none (both P < 0.01) of the RRP group. At 1 year after RRP bowel symptoms and fecal continence improved in the aRT group and there was no significant difference for these symptoms between the groups. Starting aRT early (, 12 weeks after RP) or late (> 12 weeks) had no significant effect on urinary continence, bowel symptoms and fecal incontinence. Apart from dilatation of urethral strictures in one patient in each group, no further procedures were reported during the follow-up. CONCLUSION A moderate dose of aRT after RRP had a temporary effect on subjective urinary continence at 4 months but not at 8 and 12 months. More patients receiving aRT reported significant bowel symptoms at 4 and 8 months than those with RRP only, but at 1 year most of these symptoms had resolved and there were no significant differences between the groups. [source] Incidence and mortality rates for colorectal cancer in Puerto Rico and among Hispanics, non-Hispanic whites, and non-Hispanic blacks in the United States, 1998-2002CANCER, Issue 13 2009Marievelisse Soto-Salgado MS Abstract BACKGROUND: Colorectal cancer (CRC) is the second most commonly diagnosed cancer in Puerto Rico (PR). In the United States, the incidence and mortality rates of CRC have great variation by sex and race/ethnicity. Age-standardized incidence and mortality rates of CRC in PR were assessed and compared with the rates among US Hispanics (USH), non-Hispanic whites (NHW), and non-Hispanic blacks (NHB) in the United States for the period from 1998 through 2002. Incidence and mortality trends and relative differences among racial/ethnic groups by sex and age were determined. METHODS: Age-standardized rates using the world standard population (ASR[World]) were based on cancer incidence and mortality data from the PR Central Cancer Registry and from the National Cancer Institute's Surveillance, Epidemiology, and End Results Program using the direct method. The annual percentage changes (APC) and relative risks (RR) were calculated using Poisson regression models. RESULTS: During 1998 through 2002, the APC of CRC incidence and mortality increased for men in PR, whereas descending trends were observed for other racial/ethnic groups. Overall period rates indicated that, in both sexes, Puerto Ricans had CRC incidence and mortality rates similar to those for USH, but their rates were lower than those for NHW and NHB. However, Puerto Rican men and women ages 40 years to 59 years had the greatest risk of incidence and mortality compared with their USH counterparts. CONCLUSIONS: Areas of concern include the increasing trends of CRC in PR and the higher burden of the disease among young Puerto Ricans compared with the USH population. The authors concluded that further research should be performed to guide the design and implementation of CRC prevention and education programs in PR. Cancer 2009. © 2009 American Cancer Society. [source] | |||||||||||||||||||||||||