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Selected AbstractsGetting ready for user involvement in a systematic reviewHEALTH EXPECTATIONS, Issue 2 2009Elizabeth Smith BSc MSc PhD Abstract Objective, This paper aims to support the critical development of user involvement in systematic reviews by explaining some of the theoretical, ethical and practical issues entailed in ,getting ready' for user involvement. Background, Relatively few health or social care systematic reviews have actively involved service users. Evidence from other research contexts shows that user involvement can have benefits in terms of improved quality and outcomes, hence there is a need to test out different approaches in order to realize the benefits of user involvement and gain a greater understanding of any negative outcomes. Design, Setting up a service-user reference group for a review of user involvement in nursing, midwifery and health visiting research involved conceptualizing user involvement, developing a representation framework, identifying and targeting service users and creating a sense of mutuality and reciprocity. Setting and participants, Recruitment was undertaken across England by two researchers. Members from 24 national consumer organizations were selected to participate in the review. Main variables studied, Learning was gained about finding ways of navigating consumer networks and organizations, how best to communicate our goals and intentions and how to manage selection and ,rejection' in circumstances where we had stimulated enthusiasm. Results and conclusions, Involving service users helped us to access information, locate the findings in issues that are important to service users and to disseminate findings. User involvement is about relationships in social contexts: decisions made at the early conceptual level of research design affect service users and researchers in complex and personal ways. [source] Patient involvement in clinical decision making: the effect of GP attitude on patient satisfactionHEALTH EXPECTATIONS, Issue 2 2006Benedicte Carlsen Cand. Abstract Objective, This study investigates general practitioners' (GPs) and patients' attitudes to shared decision making, and how these attitudes affect patient satisfaction. Background, Sharing of information and decisions in the consultation is largely accepted as the ideal in general practice. Studies show that most patients prefer to be involved in decision making and shared decision making is associated with patient satisfaction, although preferences vary. Still we know little about how the interaction of GP and patients' attitudes affects patient satisfaction. One such study was conducted in the USA, but comparative studies are lacking. Design, Questionnaire survey distributed through GPs. Setting and participants, The results are based on the combined questionnaires of 41 GPs and 829 of their patients in the urban municipality of Bergen in the western part of Norway. Main variables studied, The data were collected using a nine-item survey instrument constructed to measure attitudes towards patient involvement in medical consultations. The patients were also asked to rate their satisfaction with their GP. Results and conclusions, The patients had a strong preference for shared decision making. The GPs also generally preferred shared decision making, but to a lesser degree than the patients, which is the opposite of the findings of the US study. There was a positive effect of the GP's attitude towards shared decision making on patient satisfaction, but no significant effect of congruence of attitudes between patient and GP on patient satisfaction. The suggested explanation is that GPs that are positive to sharing decisions are more responsive to patients' needs and therefore satisfy patients even when the patient's attitude differs from the GPs' attitude. Hence, although some patients do prefer a passive role, it is important to promote positive attitudes towards patient involvement in medical consultations. [source] Acceptability of willingness to pay techniques to consumersHEALTH EXPECTATIONS, Issue 4 2002Susan J. Taylor PhD Abstract Objective The purpose of this study was to assess and compare the proportion of usable responses and protest votes obtained with two willingness to pay (WTP) techniques, contingent valuation (CV) and discrete choice experiment (DCE) and to assess the acceptability of the techniques to respondents. Setting and participants Pregnant women attending the public antenatal clinics of a Sydney teaching hospital were surveyed. Main variables studied Preference for either Treatment A (artificial rupture of the membranes followed by intravenous oxytocin) or Treatment B (prostaglandin E2 gel followed by oxytocin if necessary) was assessed. Then WTP for the preferred treatments was assessed using CV and WTP for specific attributes of the treatments in the DCE. In addition, the acceptability of the two techniques was compared in terms of responses deemed to be valid according to defined criteria, protest votes and comments recorded by consumers. Results With the CV, 74% of respondents chose gel and their maximum WTP was Aus$178 compared with $133 for the alternative. A total of 68% of responses were deemed to be valid including 5% who may have been expressing a protest vote. With the DCE, respondents were WTP $55 for every 1 h reduction in the length of time from induction to delivery. A total of 72% of responses were deemed valid and only two of these 258 women were considered to have expressed a protest vote. Conclusions Only a small number of women expressed objections to the use of WTP questions in health-care and the majority of women completed both questions successfully. [source] Patients' attitudes to medicines and expectations for prescriptionsHEALTH EXPECTATIONS, Issue 3 2002Nicky Britten MA MSc PhD Abstract Background, Recent research has shown that patients' expectations for prescriptions influence doctors' prescribing decisions, but little is known of the antecedents of these expectations. Objectives, To test earlier qualitative research about patients' views of medicines; to describe the demographic characteristics of those holding orthodox and unorthodox views of medicines; to investigate the relationship between patients' ideal and predicted expectations for prescriptions; and to determine the relative effects of attitudinal, demographic, organizational and illness variables on these expectations. Design, Questionnaire survey of patients consulting general practitioners. Setting and participants, A total of 544 patients and 15 doctors in four general practices. Main variables studied, Patients' attitudes to medicines; patients' demographic characteristics; organizational variables; aspects of patients' presenting problems. Outcome measures, Patients' ideal and predicted expectations for prescriptions. Results, Orthodox and unorthodox attitudes to medicines can be measured quantitatively, and ethnicity was the only demographic variable associated with both. Ideal and predicted expectations for prescriptions were closely related to each other but differed in their antecedents. Both types of expectations were associated with attitudinal, demographic, organizational and illness variables. Ideal expectations were influenced by orthodox and unorthodox attitudes to medicines, while predicted expectations were only influenced by orthodox attitudes. Conclusions, Future studies of patients' expectations for health services should distinguish between ideal and predicted expectations, and should consider the range of possible influences on these expectations. In particular, the effect of the organization and context of health services should be investigated. [source] Using focus groups to seek the views of patients dying from cancer about the care they receiveHEALTH EXPECTATIONS, Issue 3 2000Norma V. Raynes Purpose The prime purpose of the study was to investigate whether focus groups were a practical way of seeking the views of dying people and whether the information collected added to that collected by more established methods. Design A sample frame of Macmillan nurse patients was collated from which three cluster samples were randomly selected to participate in focus groups. The focus groups were structured with an experienced facilitator and recorder to answer three key questions. Setting and participants Patients of Macmillan nurses in three NHS Trusts in West Yorkshire who were living at home with incurable cancer. They were aware of their condition and were willing to participate. Main variables studied The three key questions were; what kind of help are you currently receiving? What sort of help do you want? Of the kind of help you are receiving what kind is most important to you? Results 17 patients participated in three focus groups. Participants were generally fairly able and living with spouses or relatives. They were of varying age with different types and duration of cancer. They were receiving a range of health and social services of varying importance to them. More help was particularly wanted with support for daily living, support from specialist cancer nurses, help getting out and with housework. Macmillan nurses and general practice services were highly rated in some but not all three trust areas. Conclusions We propose that focus groups are a practical way of collecting information about dying patients that can complement other sources of information in planning and auditing the provision of care. [source] Randomized clinical trial of the influence of local water-filtered infrared A irradiation on wound healing after abdominal surgeryBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 8 2006M. Hartel Background: Postoperative local water-filtered infrared A (wIRA) irradiation improves tissue oxygen partial pressure, tissue perfusion and tissue temperature, which are important in wound healing. Methods: The effect of wIRA irradiation on abdominal wound healing following elective gastrointestinal surgery was evaluated. Some 111 patients undergoing moderate to major abdominal surgery were randomized into one of two groups: wIRA and visible light irradiation (wIRA group) or visible light irradiation alone (control group). Uncovered wounds were irradiated twice a day for 20 min from days 2,10 after operation. Results: Irradiation with wIRA improved postoperative wound healing in comparison to visible light irradiation alone. Main variables of interest were: wound healing assessed on a visual analogue scale (VAS) by the surgeon (median 88·6 versus 78·5 respectively; P < 0·001) or patient (median 85·8 versus 81·0; P = 0·040), postoperative pain (median decrease in VAS score during irradiation 13·4 versus 0; P < 0·001), subcutaneous oxygen tension after irradiation (median 41·6 versus 30·2 mmHg; P < 0·001) and subcutaneous temperature after irradiation (median 38·9 versus 36·4 °C; P < 0·001). The overall result, in terms of wound healing, pain and cosmesis, measured on a VAS by the surgeon (median 79·0 versus 46·8; P < 0·001) or patient (79·0 versus 50·2; P < 0·001) was better after wIRA irradiation. Conclusion: Postoperative irradiation with wIRA can improve normal postoperative wound healing and may reduce costs in gastrointestinal surgery. Copyright © 2006 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Statutory health assessments for looked-after children: what do they achieve?CHILD: CARE, HEALTH AND DEVELOPMENT, Issue 1 2003C. M. Hill Abstract Objective To examine the outcomes of statutory health assessment of children looked after by an English City Council. Design Retrospective longitudinal documentary analysis. Setting and participants Health records of all children looked after by Southampton City Council who had attended at least two statutory health assessments within a designated paediatric service from 1996 to 1999. Main variables studied Demographic characteristics of the children; physical and mental health problems identified at assessment and extent to which health recommendations were implemented. Results Twenty-seven boys and 22 girls aged 6 months,15 years were identified who had attended at least two assessments. One-hundred and four physical and mental health needs were identified at care entry requiring further assessment or intervention. More health problems were identified for girls than boys. At care entry 15/49 of the children were not fully immunized. At review, on average 14 months later, recommendations had only been implemented in just over half of children. Conclusions In common with previous studies this work confirms that the statutory health assessment identifies health need and health neglect that may otherwise go unrecognized. Whereas children's needs and problems were diverse, many continued to suffer health neglect in the system of public care designed to help them. In order to be effective, statutory health assessments must be a health promoting rather than disease screening exercise delivered by professionals skilled to address diverse health needs. Crucially, the heath assessment can only succeed as a tool for health advocacy if complementary to and integrated with local authority care and review. [source] The impact of mineralocorticoid receptor ISO/VAL genotype (rs5522) and stress on reward learningGENES, BRAIN AND BEHAVIOR, Issue 6 2010R. Bogdan Research suggests that stress disrupts reinforcement learning and induces anhedonia. The mineralocorticoid receptor (MR) determines the sensitivity of the stress response, and the missense iso/val polymorphism (Ile180Val, rs5522) of the MR gene (NR3C2) has been associated with enhanced physiological stress responses, elevated depressive symptoms and reduced cortisol-induced MR gene expression. The goal of these studies was to evaluate whether rs5522 genotype and stress independently and interactively influence reward learning. In study 1, participants (n = 174) completed a probabilistic reward task under baseline (i.e. no-stress) conditions. In study 2, participants (n = 53) completed the task during a stress (threat-of-shock) and no-stress condition. Reward learning, i.e. the ability to modulate behavior as a function of reinforcement history, was the main variable of interest. In study 1, in which participants were evaluated under no-stress conditions, reward learning was enhanced in val carriers. In study 2, participants developed a weaker response bias toward a more frequently rewarded stimulus under the stress relative to no-stress condition. Critically, stress-induced reward learning deficits were largest in val carriers. Although preliminary and in need of replication due to small sample size, findings indicate that psychiatrically healthy individuals carrying the MR val allele, gene, which has been recently linked to depression, showed a reduced ability to modulate behavior as a function of reward when facing an acute, uncontrollable stressor. Future studies are warranted to evaluate whether rs5522 genotype interacts with naturalistic stressors to increase the risk of depression and whether stress-induced anhedonia might moderate such risk. [source] Use of multi-platform, multi-temporal remote-sensing data for calibration of a distributed hydrological model: an application in the Arno basin, ItalyHYDROLOGICAL PROCESSES, Issue 13 2006Lorenzo Campo Abstract Images from satellite platforms are a valid aid in order to obtain distributed information about hydrological surface states and parameters needed in calibration and validation of the water balance and flood forecasting. Remotely sensed data are easily available on large areas and with a frequency compatible with land cover changes. In this paper, remotely sensed images from different types of sensor have been utilized as a support to the calibration of the distributed hydrological model MOBIDIC, currently used in the experimental system of flood forecasting of the Arno River Basin Authority. Six radar images from ERS-2 synthetic aperture radar (SAR) sensors (three for summer 2002 and three for spring,summer 2003) have been utilized and a relationship between soil saturation indexes and backscatter coefficient from SAR images has been investigated. Analysis has been performed only on pixels with meagre or no vegetation cover, in order to legitimize the assumption that water content of the soil is the main variable that influences the backscatter coefficient. Such pixels have been obtained by considering vegetation indexes (NDVI) and land cover maps produced by optical sensors (Landsat-ETM). In order to calibrate the soil moisture model based on information provided by SAR images, an optimization algorithm has been utilized to minimize the regression error between saturation indexes from model and SAR data and error between measured and modelled discharge flows. Utilizing this procedure, model parameters that rule soil moisture fluxes have been calibrated, obtaining not only a good match with remotely sensed data, but also an enhancement of model performance in flow prediction with respect to a previous calibration with river discharge data only. Copyright © 2006 John Wiley & Sons, Ltd. [source] Water absorption properties of phosphate glass fiber-reinforced poly-,-caprolactone composites for craniofacial bone repairJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Levent Onal Abstract The moisture uptake of polymers and composites has increasing significance where these materials are specified for invasive, long-term medical applications. Here we analyze mass gain and the ensuing degradation mechanisms in phosphate glass fiber reinforced poly-,-caprolactone laminates. Specimens were manufactured using in situ polymerization of ,-caprolactone around a bed of phosphate glass fibers. The latter were sized with 3-aminopropyltriethoxysilane to control the rate of modulus degradation. Fiber content was the main variable in the study, and it was found that the moisture diffusion coefficient increased significantly with increasing fiber volume fraction. Diffusion, plasticization, and leaching of constituents appear to be the dominant aspects of the process over these short-term tests. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008 [source] Factors Controlling the Abundance and Size Distribution of the Phototrophic Ciliate Myrionecta rubra in Open Waters of the North AtlanticTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2008DAVID J. S. MONTAGNES ABSTRACT. Myrionecta rubra, a ubiquitous planktonic ciliate, has received much attention due to its wide distribution, occurrence as a red tide organism, and unusual cryptophyte endosymbiont. Although well studied in coastal waters, M. rubra is poorly examined in the open ocean. In the Irminger Basin, North Atlantic, the abundance of M. rubra was 0,5 cells/ml, which is low compared with that found in coastal areas. Distinct patchiness (100 km) was revealed by geostatistical analysis. Multiple regression indicated there was little relationship between M. rubra abundance and a number of environmental factors, with the exception of temperature and phytoplankton biomass, which influenced abundance in the spring. We also improve on studies that indicate distinct size classes of M. rubra; we statistically recognise four significantly distinct width classes (5,16, 12,23, 18,27, 21,33 ,m), which decrease in abundance with increasing size. A multinomial logistic regression revealed the main variable correlated with this size distribution was ambient nitrate concentration. Finally, we propose a hypothesis for the distribution of sizes, involving nutrients, feeding, and dividing of the endosymbiont. [source] Realist Visions of the End of the Cold War: Morgenthau, Aron and WaltzBRITISH JOURNAL OF POLITICS & INTERNATIONAL RELATIONS, Issue 2 2009Marco Cesa Although realist theory did not predict the end of the cold war, prominent realist scholars such as Hans Morgenthau, Raymond Aron and Kenneth Waltz did give some thought to the conditions under which the cold war might be settled. Both Aron and Morgenthau characterised the cold war as a combination of traditional power politics and ideological competition, but they differed on the relative weight of each component. For Morgenthau, a diplomatic settlement would deactivate the unsettling potential of the ideological conflict; for Aron, only the disappearance of the ideological conflict could pave the way to some lasting diplomatic settlement. For Waltz, ideology had little impact; the bipolar structure of the international system was the main variable on which both the cold war and its end depended. [source] A mouse model of lupin allergyCLINICAL & EXPERIMENTAL ALLERGY, Issue 8 2009N. E. Vinje Summary Background Lupin has been introduced as a new food ingredient in an increasing number of European countries, resulting in reports of allergic reactions mostly due to cross-reactions in peanut-allergic individuals. Some cases of primary lupin allergy have also been reported. Objective The aim of our study was to develop a food allergy model of lupin in mice with anaphylaxis as the endpoint and further, to develop an approach to estimate the allergen dose inducing maximal sensitization using a statistical design requiring a limited number of animals. Methods Mice were immunized by intragastric gavage using cholera toxin as an adjuvant. A two-compartment response surface design with IgE as the main variable was used to estimate the maximal sensitizing dose of lupin in the model. This estimated dose was further used to evaluate the model. The mice were challenged with a high dose of lupin and signs of an anaphylactic reaction were observed. Antibody reactions (IgE and IgG2a), serum mast cell protease [mouse mast cell protease-1 (MMCP-1)] and ex vivo production of cytokines (IL-4, IL-5 and IFN-,) by spleen cells were measured. An immunoblot with regard to IgE binding was also performed. Results The dose that elicited the maximal sensitization measured as IgE was 5.7 mg lupin protein per immunization. Mice that received this dose developed anaphylactic reactions upon challenge, IgE against several proteins in the lupin extract, and high levels of MMCP-1, and showed a general shift towards a T-helper type 2 response. Post-challenge serum MMCP-1 levels corresponded to the seriousness of the anaphylactic reactions. Conclusion We have established a mouse model with clinical symptoms of lupin allergy, with an optimized dose of lupin protein. A statistical design that can be used to determine an optimal immunization dose with the use of a minimum of laboratory animals is described. [source] Near threshold fatigue crack growth versus long finite lifeFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8-9 2002P. C. PARIS ABSTRACT A brief review of the discovery of the fatigue crack growth threshold is provided with a discussion of the main variables, Kmax and ,K, which control the threshold over the low and high load ratio ranges, respectively. The significant effect on near threshold growth rates as illustrated by Donald are shown, for an example the aluminium alloy, 2324-T39. Attention is then turned to the ,partial closure model' as a means of correlating near threshold fatigue crack growth rates. This seems to be the most promising model with a physical basis. For this reason, the discussion goes on to present a new theoretical analysis of the load displacement record characteristics, which should accompany ,partial closure' of fatigue cracks. In addition it is concluded that secondary stress effects should be explored for near threshold fatigue crack growth rates. [source] Thermal effects in partially saturated soils: a constitutive modelINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 9 2005Gabriella Bolzon Abstract The present paper is centred on the assessment of an elastic,plastic model for partially saturated soils, earlier proposed by the authors, for its predictive capability with respect to temperature changes, on the light of available experimental results. The model is cast within a constitutive framework that uses Bishop's stress and suction as main variables governing the volumetric response of the material. Some enhancement to the original temperature-independent formulation is proposed. In particular, functions describing the yield surface and the compressibility modulus are modified to account for the shrinking of the elastic domain and for the increase of irreversible volumetric strain with heating. Some examples illustrate the main features of the present proposal. Comparison with some experimental results is also included. Copyright © 2005 John Wiley & Sons, Ltd. [source] A thermal nonlinear dynamic model for water tube drum boilersINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 1 2010M. A. Habib Abstract A thermal model for the prediction of possible tube overheating was developed. The model incorporates a nonlinear state space dynamic model that captures the important physical interactions of the main variables of steam generation in naturally circulated water tube drum boilers. This paper provides an investigation of the dynamic effects of rapid rise in fuel flow rate (heat input) on the thermal and flow characteristics of the riser tubes in natural circulation water tube boilers. The system under consideration includes the drum, riser and downcomer as its major components. The dynamic response of the system's state variables due to rapid rises in fuel flow rates was investigated. The results show that the sudden rise in the firing rate is followed by an increase in the steam quality, which is accompanied by a decrease in the circulation rate as a result of increase in the pressure. The riser temperature increases slightly above the saturation temperature due to the increase in the steam temperature and due to the dynamic influence resulting from sudden increase in the heat flux. The present calculations of the water level in the drum provide good comparison with those in the literature. Copyright © 2009 John Wiley & Sons, Ltd. [source] The GlideScope Ranger® video laryngoscope can be useful in airway management of entrapped patientsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 10 2009A. R. NAKSTAD Background: Airway management of entrapped patients is challenging and alternatives to endotracheal intubation with a Macintosh laryngoscope must be considered. In this study, the GlideScope Ranger® video laryngoscope has been evaluated as an alternative to standard laryngoscopy. Methods: Eight anaesthesiologists from a Helicopter Emergency Medical Service intubated the trachea of a Laerdal SimMan® manikin using the studied laryngoscopes in two scenarios: (A) unrestricted access to the manikin in an ambulance and (B) no access from the head end, simulating an entrapped patient. The time used to secure the airway and the scored level of difficulty were the main variables. Results: In scenario A, all anaesthesiologists managed to secure the airway using both techniques within the 60-s time limit. In scenario B, all secured the airway when using the video laryngoscope, while 50% succeeded with endotracheal intubation using the Macintosh laryngoscope. The difference in the success rate was statististically significant (P=0.025). There were no significant differences in the time spent on endotracheal intubation in the two scenarios or between the devices. All stated that the availability of a video laryngsoscope would make drug-facilitated intubation a realistic alternative when access to patients is limited. The lack of visual control when using the Macintosh laryngoscope excludes this technique in real-life settings. Conclusion: This study suggests that the Glidescope Ranger® may be merited in situations requiring endotracheal intubation by an experienced intubator in patient entrapment. Further studies are required to clarify whether performance in patients mimics that in a manikin. [source] Earlywood vessel size of oak as a potential proxy for spring precipitation in mesic sitesJOURNAL OF BIOGEOGRAPHY, Issue 12 2008Patrick Fonti Abstract Aim, In this study, we evaluate the importance of the mean earlywood vessel size of oaks as a potential proxy for climate in mesic areas. Location, The study was conducted in Switzerland at three forest sites dominated by oak (Quercus petraea and Q. pubescens). The three sites were in different climatic zones, varying mainly in terms of precipitation regime. Methods, Three 50-year-long site chronologies of mean earlywood vessel size and tree-ring widths were obtained at each site and related to monthly meteorological records in order to identify the main variables controlling growth. The responses of mean vessel size to climate were compared with those of the width variables to evaluate the potential climatic information recorded by the earlywood vessels. Results, The results show that the mean vessel size has a different and stronger response to climate than ring-width variables, although its common signal and year-to-year variability are lower. This response is better in particular at mesic sites, where it is linked to precipitation during spring, i.e. at the time of vessel formation, and is probably related to the occurrence of only a few processes controlling vessel growth, whereas radial increment is controlled by multiple and varying factors. Main conclusions, The mean earlywood vessel size of oak appears to be a promising proxy for future climate reconstructions of mesic sites, where radial growth is not controlled by a single limiting factor. [source] INFLUENCE OF PLATE TEMPERATURE AND MODE OF REHYDRATION ON TEXTURAL PARAMETERS OF PRECOOKED FREEZE-DRIED BEEFJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2003ANA MARIA IRENE BARTOLOMEU AYROSA The effects of various plate temperatures and rehydration procedures in texture of precooked freeze-dried beef, were evaluated. Frozen precooked commercial beef was freeze-dried at 20, 40, 60 and 80C during 24 h. The rehydration procedure involved two main variables: distilled water at room-temperature and at 80C, for 30 min. The texture profile analysis was performed with a TA-XT2 Texture Analyzer (SMS) for freeze-dried rehydrated samples and compared to frozen precooked beef. The results showed that with a same drying period, the 60C plate temperature and rehydrated in distilled water at room-temperature resulted in a better product texture, in regards to texture parameters hardness and chewiness. [source] Accuracy of orientation distribution function determination based on EBSD data-A case study of a recrystallized low alloyed Zr sheetJOURNAL OF MICROSCOPY, Issue 3 2007N. BOZZOLO Summary The question of the statistical accuracy of EBSD data for global texture calculation was re-explored on the basis of a very large grain population (83 000 grains measured on a recrystallized low-alloyed Zr sheet). Previous works aimed mainly at identifying and quantifying the main texture components and were based on much smaller data sets. The present work attempts to quantify the accuracy of the complete texture, including low-density regions of the orientation space. For that purpose, a new statistical parameter, V,, based on the calculation of texture difference functions is proposed. This parameter has two main advantages: it is equally sensitive to both high and low peaks of the orientation density function (ODF), and it has a physical interpretation because it is the material volume fraction corresponding to the difference between a given ODF and a reference ODF (considered, or known to be close to the truth). Two main variables were studied: the number of grains taken into account and the peak width ,0 of Bunge's ,Gaussian' model density used as kernel for the actual analysis. The orientation distribution functions were computed by nonparametric kernel density estimation with harmonics up to the order of 34. Minimizing the value of V, serves as the objective function for optimizing the peak width ,0 as a function of the number of grains. The properties of the V, parameter also allows for the definition of a method for estimating the accuracy of a given texture that has been obtained from a limited number of grains, without knowing the true texture of the investigated material. [source] Optimization of extraction process for phenolic acids from black cohosh (Cimicifuga racemosa) by pressurized liquid extraction,JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 1 2006Sudarsan Mukhopadhyay Abstract An investigation to optimize the extraction of phenolic acids from black cohosh using a pressurized liquid extractor system was studied with the aim of developing a generalized approach for sample preparation of phenolic compounds from plant matrices. Operating parameters such as solvent composition, solid-to-solvent ratio, temperature, particle size distribution, and number of extraction cycles were identified as main variables that influence extraction efficiency. A mixture of methanol and water (60:40 v/v) was found to be the best solvent for total phenolics (TP) and individual phenolic acids. The four phenolic acids extracted from black cohosh were identified by HPLC and LC-MS as caffeic acid, ferulic acid, sinapic acid and isoferulic acid. Over 96% of the measured phenolics were extracted in first two cycles. The extraction efficiency for black cohosh with MeOH:H2O (60:40 v/v) was found to be maximum at a solid-to-solvent ratio of 80 mg ml,1. TP content of the extract was found to increase with temperature up to 90 °C. Particle size was found to have a large impact on extraction efficiency of TP. Samples with particle size between 0.25 mm and 0.425 mm provided optimum extraction of phenolics from black cohosh. Published in 2005 for SCI by John Wiley & Sons, Ltd. [source] An analysis of UK franchise contracting 1989,1999MANAGERIAL AND DECISION ECONOMICS, Issue 1 2003Jonathan S. Seaton This paper examines UK franchise contracts over the period 1989,1999. Franchising is modelled as comprising three main variables, contract length, royalty rate and initial franchise fee. Up to now most authors have concentrated on the latter two variables, but with the data in this paper it is possible to assess the characteristics that impact on all three. Further, our analysis looks at what affects the probability of contract change. We take account of the limited dependent variable nature of the data and exploit sectoral heterogeneity. Our main findings are that the focus of attention on ,aggregate' variables is inappropriate and that contract length appears to be an important aspect of the franchise contract which is theoretically obvious, but until now has not been empirically tested. Copyright © 2003 John Wiley & Sons, Ltd. [source] Dynamics of Interpersonal Political Environment and Party Identification: Longitudinal Studies of Voting in Japan and New ZealandPOLITICAL PSYCHOLOGY, Issue 4 2005Ken'ichi Ikeda The dynamical systems theory of groups claims that interpersonal political environment and party identification are dynamically interrelated to provide heuristics under uncertainty. Panel data over the course of a year examined the longitudinal dynamics between social networks, social identifications, and voting behavior among a national sample of registered voters in Japan and a regional sample in Wellington, New Zealand. Respondents with more stable party identification had greater stability in the political preferences of their interpersonal network in both countries; moreover, stability in party identification was predicted by interpersonal political environment and older age in both countries. Stability of party identification predicted voting consistency in both countries, whereas stability of interpersonal political environment made an independent contribution to voting consistency in Japan only. There were cultural differences in levels of interpersonal political environment stability, but the amount of political discussion and ideological stability did not make independent contributions to any of the three main variables. Results provided support for the dynamical systems theory of groups. [source] Cold and hot gas filtration using a novel mobile granular bed with an inner fluidized sectionTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2002Nicolas Abatzoglou Abstract Two experimental studies were conducted with a novel moving granular bed filter (NMGBF). The first one was performed on a cold and dry mock-up module operated at room temperature and was aimed at a) proving the concept, b) establishing the operating patterns and flow profiles and c) optimizing the operating conditions. The gas flowrate and the geometry of the filter were the main variables studied. The second study was conducted on a prototype hot filter PDU (Process Development Unit) under real time operating conditions. The filter was one of the modules of a hot-gas-conditioning-train in a fluidized bed gasifier. Results showed similar particles collection efficiency for hot- and cold-dry filtration. The filter showed an efficiency of 99.9% over 55 h filtration time for particles larger than 1 ,m, while for submicronic particles the efficiency is between 84% and 96% (weight basis). This paper presents and discusses the apparatus, the experimental methods and conditions as well as characteristic results on the two prototypes used. Deux études expérimentales ont été menées à I'aide d'un nouveau filtre à lit granulaire mobile (NMGBF). La premiére a été menée sur une maquette froide et séche à la température ambiante et visait a (a) prouver le concept, (b) établir les modéles de fonctionnement et les profus d'écoulement et (c) optimiser les conditions opératoires. Les variables étudiées sont le débit de gaz et la géométrie du filtre La seconde étude a été menée sur une unite de développement de procédes prototype à filtre chaud dans des conditions opératoires en temps réel. Le filtre est un des modules du train de conditionnement à gaz chaud dans un gazéificateur à lit fluidise. Les résultats montrent une efficacite de collecte des particules comparable pour la filtration sèche chaude et froide. Le filtre montre une efficacité de 99,9 % pour un temps de filtration de 55 h avec des particules au-dessus de 1 ,m, alors qu'avec des particules inférieur au micron I'efficacite' se situe entre 84 et 96 % (sur la base massique). On décrit dans cet article I'appareil, les méthodes expérimentales et les conditions, ainsi que les résultats caractéristiques des deux prototypes utilisés. [source] Antinuclear Autoantibodies, Complement Level, Hypergammaglobulinemia and Spontaneous Intrauterine Hematoma in Pregnant WomenAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2003Jaume Alijotas Problem: To examine the associative relationship among autoantibodies, C4 levels and intrauterine hematomas (IUH) in more detail than in the studies published earlier. Method Of Study: We performed a retrospective study of 54 women with poor obstetric outcomes. Sera were screened for antinuclear antibodies (ANA), anti-DNA antibodies, antiphospholipid antibodies (aPL), and antithyroid antibodies. C4-complement and gammaglobulin levels were also monitored. We compared the main variables in IUH complicated pregnancy group with the risk pregnancy group without IUH. We also compared these variables in the IUH cases before and during IUH. Results: Eight IUH were detected. The average number of spontaneous losses for these eight women was 3.3 ± 2.1 (range: 1,8). aPL was present in 100% of cases. ANAs and hypergammaglobulinemia were present in 50% of cases and low C4 in 87.5% of cases. After comparing these variables apart from C4 before and during IUH, we found no statistical differences. However, C4 was low in four patients before IUH and in seven patients during IUH (OR: 7.0; 95% CI: 0.57,86.33). When we compared autoantibodies apart from lupus anticoagulant (LAC) between the two groups, no differences were observed. However, seven of the eight (87.5%) patients with IUH were LAC positive whereas only 24 of the 46 patients (52.1%) were positive in the non-IUH group (OR: 6.42; 95% CI: 0.73,56.41). Rapid plasma reagin was present in 8/46 in the non-IUH group (16.7%) and 5/8 in the IUH group (62.5%) P < 0.015). Conclusions: In women with poor obstetric histories, autoantibodies, especially antiphospholid antibodies, may play a role in the IUH development especially if low C4 and/or hypergammaglobulinemia are present. [source] Incidence of changes and predictive factors for sexual function after coronary stentingANDROLOGIA, Issue 1 2007H. Shi Summary The study was aimed at determining the incidence of changes in sexual function and identifying the possible associated variables of erectile dysfunction (ED) in coronary artery disease (CAD) patients undergoing coronary stenting. Four hundred and sixty-seven patients were retrospectively contacted with a questionnaire regarding sexual function from 6 months pre-stenting to 6 months post-stenting by telephone follow up. Univariate analyses were used to determine prognostic variables. ED changed following stenting in CAD (P < 0.05), in acute coronary syndrome (ACS) (P > 0.05) and in chronic coronary syndrome (CCS) (P < 0.05). Sexual activity was not resumed in 8.1%, was unchanged in 33.8%, increased in 0% and decreased in 58.0%. The average frequency of sexual activity decreased every month in CAD (P < 0.05), in ACS (P < 0.05) and in CCS (P < 0.01) after undergoing coronary stenting respectively. The mean time interval between the onset of ED and CAD was 33 months. Resuming sexual activity after stenting varied from 2 weeks to 30 months. Significant predictors of ED after coronary stenting were mean age, diabetes mellitus, 2,3-vessel disease or current smoking status. It was concluded that coronary stenting had a significant incidence of ED. Mean age, diabetes mellitus, 2,3-vessel disease or current smoking status showed to be the main variables associated with ED. Attempts to improve individual secondary prevention outcomes (controlling serum glucose and smoking cessation) should be designed. [source] Long-term efficacy and safety results of the two-stage implantation technique in sacral neuromodulationBJU INTERNATIONAL, Issue 9 2002W.A. Scheepens Objective ,To assess the long-term efficacy and safety of two-stage sacral neuromodulation with an implantable pulse generator (IPG) in patients treated for urinary urge incontinence (UI) and/or urinary retention (UR). Patients and methods ,The two-stage technique is used if patients have a good response during the acute phase of the percutaneous nerve evaluation (PNE) test, but have a poor response during the following 4,7 days (subchronic phase). In the first stage only the permanent electrode was implanted and connected to a temporary external stimulator, allowing patients to be assessed for longer. If the main symptoms improved by more than half the patient proceeded to the second stage, the insertion of the IPG. We reviewed all patients who underwent two-stage implantation; all had signed an informed consent and were asked to complete voiding diaries and a questionnaire to assess the subjective effects of the therapy. Safety was assessed from relevant medical events, management, and relative to the thera-py and resolution. Residual urine was assessed by self-catheterization. The long-term voiding diary results were compared with baseline estimates and analysed statistically using the two-sided Student's t -test. Results ,Between 1991 and 1998, 15 patients (13 women and two men, mean age 53 years, range 44,66) underwent the two-stage technique; the mean (median, range) follow-up was 4.9 (5.2, 2.5,7.5) years. Seven patients had UI and seven had UR, with one having both. The mean (range) number of PNEs undertaken in each patient was 2.1 (1,4) and these all failed in the subchronic phase. All patients underwent a first- and second-stage implant after a mean (range) screening period of 12.2 (2,29) days. One patient was explanted after implantation of only the first stage, and two others explanted in a later phase because the IPG was ineffective during the follow-up. The voiding diary results of the remaining 12 patients showed improvement in all the main variables, and in the subjective assessment 11 reported an improvement and were satisfied with the therapy. There were 17 adverse events, 14 of which were resolved and seven of which required surgical intervention. Conclusion ,The long-term results of the two-stage implantation show clinically and statistically significant improvements, probably because the implantation of the lead (first stage) more closely resembles the final therapy. If a temporary PNE test is not optimal (lead migration, longer testing needed), the two-stage technique can offer a good and safe alternative of comparable efficacy in the long-term. If the two-stage technique had not been available to these 12 patients they would not have been offered neuromodulation. [source] New Predictive Correlations for the Drop Size in a Rotating Disc Contactor Liquid-Liquid Extraction ColumnCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 2 2007M. Ismail Al-Rahawi Abstract Sauter mean drop sizes (d32) generated from a hole distributor in liquid extraction RDC columns were studied under various conditions. Experiments were designed to generate data required to determine the main variables that control the drop sizes in RDCs. Two precise correlations were proposed for predicting d32 in a RDC extraction column. The first was based on operating variables, hole-distributor diameter, disc speed, column geometry, and system physical properties. The second one considered the same variables, except the column geometry. This model can be used for design purposes. The two correlations are the first of their type to consider the distributor hole inlet diameter in a RDC column. This diameter has been neglected by previous investigators. The maximum standard deviation for all data is 0.75,%, with a maximum absolute error of 6.8,%. [source] |