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Selected AbstractsThe Dynamic Interaction of Water with Four Dental Impression Materials During CureJOURNAL OF PROSTHODONTICS, Issue 4 2009Dariush Hosseinpour PhD Abstract Purpose: The purpose of this work was to investigate the interaction of water with four different dental impression materials: Aquasil (Ultra XLV Type 3), Take 1 (Wash Regular Set), Genie (Light Body, Standard Set), and Impregum Garant (Soft Light Bodied Consistency). Materials and Methods: Apparent contact angles of de-ionized water made against thin horizontal sample films of the different materials under different conditions were measured from analysis of profile images of symmetrical sessile drops of water placed on the sample films using a Model FTÅ200 dynamic drop shape analysis system, which included a JAI M30 high speed CCD camera combined with a zoom microscope. Data were taken for specimens of dry ages (times following mixing) from a minimum of 20 seconds up to 1220 seconds. Imaging was started before the initial water/impression material contact, and lasted for at least 420 seconds in each case. The interval at the beginning of each run was 0.033 second, and then increased by a factor of 1.012 to the end. During the initial 3 seconds following the drop deposition, the drop's shape oscillated due to inertial effects, so apparent contact angle data during this period were neglected in all cases. All measurements were made at room temperature. The drops were enclosed in a humidified chamber that suppressed evaporation. All data were repeated at least five times, and results were analyzed where appropriate using one-way ANOVA. Microscopic images of the water/impression material interactions for fresh (uncured) materials were acquired to reveal the destructive interactions that resulted from such contact. Finally, surface tension measurements were made of water that had been contacted with material of varying dry age using the pendant drop method capability of the drop shape analysis system. These helped to assess the origin of hydrophilicity development for the different materials. Results: For short curing times (dry ages), water showed a destructive effect on the integrity of all of the impression materials, as evidenced by the formation of a crater beneath the water drop and a scum of material at its surface. These effects diminished with dry age until a critical curing time was reached, beyond which such destructive interactions were no longer detectable. These critical curing times were determined to be 80, 140, 110, and 185 seconds for Aquasil, Take 1, Genie, and Impregum, respectively. The initial contact angle following the respective critical curing time was lowest for Impregum, at 66°; while values for Aquasil, Genie, and Take 1 were 93°, 104°, and 110°, respectively. Beyond the critical curing times for the different materials, different degrees of hydrophilicity were observed. Aquasil showed the lowest final contact angle (<10°), with Impregum, Take 1, and Genie showing 31°, 34°, and 40°, respectively. Measurements of the surface tension of water after contact with the different materials suggested that for Aquasil, hydrophilicity appears to be developed through the leaching of surfactant from the material, whereas for Impregum, Take 1, and Genie, hydrophilicity is developed at least in part through a change in surface structure in contact with water. Impregum and Aquasil materials of dry ages well beyond the critical curing time exhibited a stick-slip behavior in their interline movement or contact angle evolution. This was believed to be due to the slowness in the leaching of surfactant (in the case of Aquasil) or the re-orientation of unleachable surface groups (in the case of the other materials) in comparison to the inherent kinetics of water drop spreading. Conclusions: All materials investigated in the fresh, uncured state showed qualitative decomposition when put in contact with water through the formation of a crater beneath the water drop and a scum of material at its surface. These effects diminished with curing time until beyond a critical value, no such effects were evident. The initial hydrophilicity of the materials as determined by the contact angles obtained at their respective critical dry ages was greatest for Impregum. Beyond the critical curing time, different degrees of hydrophilicity were observed, with Aquasil showing the lowest final contact angle. [source] Unofficial international conflict resolution: Is there a Track 1½?CONFLICT RESOLUTION QUARTERLY, Issue 1 2009Are there best practices? Analysis of twenty-four cases of unofficial international conflict resolution initiatives, done according to similarities across seven variables, shows that the practice of "Track 1½" diplomacy is distinct from Track 2 diplomacy. Furthermore, these initiatives are distinguished by their focus on process or diverse goals. Multidimensional scaling organized the cases into four groupings of similar initiatives: Track 1½ process-focused, Track 1½ diversified, Track 2 process-focused, and Track 2 diversified. The variety of approaches used in these twenty-four cases of high-quality international conflict resolution initiatives suggests best practices. These practices should be considered sensitive to context rather than a standard set of procedures used regardless of conflict environment. [source] Neural selectivity for hue and saturation of colour in the primary visual cortex of the monkeyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2000Akitoshi Hanazawa Abstract In the inferior temporal (IT) cortex of monkeys, which has been shown to play a critical role in colour discrimination, there are neurons sensitive to a narrow range of hues and saturation. By contrast, neurons in the retina and the parvocellular layer of the lateral geniculate nucleus (pLGN) encode colours in a way that does not provide explicit representation of hue or saturation, and the process by which hue- and saturation-selectivity is elaborated remains unknown. We therefore tested the colour-selectivity of neurons in the primary visual cortex (V1) and compared it with those of pLGN and IT neurons. Quantitative analysis was performed using a standard set of colours, systematically distributed within the CIE (Commission Internationale de l'Eclairage)-xy chromaticity diagram. Selectivity for hue and saturation was characterized by analysing response contours reflecting the overall distribution of responses across the chromaticity diagram. We found that the response contours of almost all pLGN neurons were linear and broadly tuned for hue. Many V1 neurons behaved similarly; nonetheless, a considerable number of V1 neurons had clearly curved response contours and were selective for a narrow range of hues or saturation. The relative frequencies of neurons exhibiting various selectivities for hue and saturation were remarkably similar in the V1 and IT cortex, but were clearly different in the pLGN. Thus, V1 apparently plays a very important role in the conversion of colour signals necessary for generating the elaborate colour selectivity observed in the IT cortex. [source] B-domain deleted recombinant factor VIII preparations are bioequivalent to a monoclonal antibody purified plasma-derived factor VIII concentrate: a randomized, three-way crossover studyHAEMOPHILIA, Issue 2 2005C. M. Kessler Summary., Background:, Deletion of the B-domain of recombinant blood coagulation factor VIII (BDDrFVIII) increases the manufacturing yield of the product but does not impair in vitro or in vivo functionality. BDDrFVIII (ReFacto®) has been developed with the additional benefit of being formulated without human albumin. Objective:, The primary objective of this three-way crossover-design study was to compare the pharmacokinetic (PK) parameters of two BDDrFVIII formulations (one reconstituted with 5 mL of sterile water, the other reconstituted with 4 mL sodium chloride 0.9% USP) with those of a plasma-derived, full-length FVIII preparation (Hemofil® M) in patients with haemophilia A to determine bioequivalence. Methods:, A series of blood samples were collected over a period of 48 h after i.v. administration of each of the FVIII preparations. Plasma FVIII activity was determined using a validated chromogenic substrate assay. Plasma FVIII activity vs. time curves was characterized for a standard set of PK parameter estimates. Two parameter estimates, the maximum plasma concentration (Cmax) and the area under plasma concentration vs. time curves (AUCs), were used to evaluate bioequivalence. The two preparations were considered bioequivalent if the 90% confidence intervals for the ratio of geometric means for Cmax and AUCs fell within the bioequivalence window of 80% to 125%. Results/Conclusion:, Results show that each BDDrFVIII formulation is bioequivalent to Hemofil M and the two formulations of BDDrFVIII are bioequivalent to each other. [source] The mitochondrial genome of the bristletail Petrobius brevistylis (Archaeognatha: Machilidae)INSECT MOLECULAR BIOLOGY, Issue 3 2006L. Podsiadlowski Abstract The complete mitochondrial genome of the bristletail Petrobius brevistylis has been determined. The genome is 15 698 bp long and bears the standard set of genes common to all arthropods as well as a major non-coding A + T-rich region, the putative mitochondrial control region. A unique gene order was revealed as it differs from other hexapod and crustacean mitochondrial genomes in the position of tRNA-Tyr. Genome features like nucleotide composition and codon usage are compared with that of other insect taxa. A + T content is similar in species of Archaeognatha and Zygentoma, but obviously lower than in Collembola and Pterygota. This A + T bias significantly affects also amino acid frequencies and may be a problem for phylogenetic analyses. [source] Outcomes of the International Union of Crystallography Commission on Powder Diffraction Round Robin on Quantitative Phase Analysis: samples 2, 3, 4, synthetic bauxite, natural granodiorite and pharmaceuticalsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2002Nicola V. Y. Scarlett The International Union of Crystallography (IUCr) Commission on Powder Diffraction (CPD) has sponsored a round robin on the determination of quantitative phase abundance from diffraction data. The aims of the round robin have been detailed by Madsen et al. [J. Appl. Cryst. (2001), 34, 409,426]. In summary, they were (i) to document the methods and strategies commonly employed in quantitative phases analysis (QPA), especially those involving powder diffraction, (ii) to assess levels of accuracy, precision and lower limits of detection, (iii) to identify specific problem areas and develop practical solutions, (iv) to formulate recommended procedures for QPA using diffraction data, and (v) to create a standard set of samples for future reference. The first paper (Madsen et al., 2001) covered the results of sample 1 (a simple three-phase mixture of corundum, fluorite and zincite). The remaining samples used in the round robin covered a wide range of analytical complexity, and presented a series of different problems to the analysts. These problems included preferred orientation (sample 2), the analysis of amorphous content (sample 3), microabsorption (sample 4), complex synthetic and natural mineral suites, along with pharmaceutical mixtures with and without an amorphous component. This paper forms the second part of the round-robin study and reports the results of samples 2 (corundum, fluorite, zincite, brucite), 3 (corundum, fluorite, zincite, silica flour) and 4 (corundum, magnetite, zircon), synthetic bauxite, natural granodiorite and the synthetic pharmaceutical mixtures (mannitol, nizatidine, valine, sucrose, starch). The outcomes of this second part of the round robin support the findings of the initial study. The presence of increased analytical problems within these samples has only served to exacerbate the difficulties experienced by many operators with the sample 1 suite. The major difficulties are caused by lack of operator expertise, which becomes more apparent with these more complex samples. Some of these samples also introduced the requirement for skill and judgement in sample preparation techniques. This second part of the round robin concluded that the greatest physical obstacle to accurate QPA for X-ray based methods is the presence of absorption contrast between phases (microabsorption), which may prove to be insurmountable in some circumstances. [source] Outcomes of the International Union of Crystallography Commission on Powder Diffraction Round Robin on Quantitative Phase Analysis: samples 1a to 1hJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2001Ian C. Madsen The International Union of Crystallography (IUCr) Commission on Powder Diffraction (CPD) has sponsored a round robin on the determination of quantitative phase abundance from diffraction data. Specifically, the aims of the round robin were (i) to document the methods and strategies commonly employed in quantitative phase analysis (QPA), especially those involving powder diffraction, (ii) to assess levels of accuracy, precision and lower limits of detection, (iii) to identify specific problem areas and develop practical solutions, (iv) to formulate recommended procedures for QPA using diffraction data, and (v) to create a standard set of samples for future reference. Some of the analytical issues which have been addressed include (a) the type of analysis (integrated intensities or full-profile, Rietveld or full-profile, database of observed patterns) and (b) the type of instrument used, including geometry and radiation (X-ray, neutron or synchrotron). While the samples used in the round robin covered a wide range of analytical complexity, this paper reports the results for only the sample 1 mixtures. Sample 1 is a simple three-phase system prepared with eight different compositions covering a wide range of abundance for each phase. The component phases were chosen to minimize sample-related problems, such as the degree of crystallinity, preferred orientation and microabsorption. However, these were still issues that needed to be addressed by the analysts. The results returned indicate a great deal of variation in the ability of the participating laboratories to perform QPA of this simple three-component system. These differences result from such problems as (i) use of unsuitable reference intensity ratios, (ii) errors in whole-pattern refinement software operation and in interpretation of results, (iii) operator errors in the use of the Rietveld method, often arising from a lack of crystallographic understanding, and (iv) application of excessive microabsorption correction. Another major area for concern is the calculation of errors in phase abundance determination, with wide variations in reported values between participants. Few details of methodology used to derive these errors were supplied and many participants provided no measure of error at all. [source] Nursing competence 10 years on: fit for practice and purpose yet?JOURNAL OF CLINICAL NURSING, Issue 10 2008Ann Bradshaw PhD, Dip N Aims and objectives., This paper examines how nurses are prepared to be clinically competent and safe at registration, so that they are fit for practice and purpose. It follows up two papers on competence published in 1997 and 1998 and investigates subsequent developments. Background., In 1979, major changes in nursing affected nurse education and preparation for competence. In the following two decades, it became clear that nurses lacked clinical skills. This paper examines subsequent changes and asks the question whether this crucial shortcoming has now been remedied. This paper considers the background and context of change in nursing and nurse education in the 1980s. It looks at the new ideology, to prepare the ,knowledgeable doer' and examines the consequences of the change on nursing competency from the 1990s to the present day. Methods., This is a position paper. Professional policy documents from the English National Board for Nursing, Midwifery and Health Visiting, United Kingdom Central Council for Nursing, Midwifery and Health Visiting and Nursing and Midwifery Council, government reports and legislation on nursing and relevant nursing literature are examined and critically analysed and conclusions drawn. Conclusions., From 1923,1977, mandatory nursing syllabuses set by the General Nursing Council of England and Wales required the registered nurse to have acquired certain specific clinical skills. These were rigorously tested to an explicit standard set by the General Nursing Council before a nurse was awarded state registration. Twenty-five years later, the loss of this system for ensuring this competence and the implications of this loss, have been widely recognised. As a result, many nurse training institutions have introduced clinical skills laboratories, simulation of practice and the Objective Structured Clinical Examination. However, to the authors' surprise and contrary to their initial expectations, the Nursing and Midwifery Council has not made these systems uniform or mandatory and so still has no way of ensuring all nurse training is producing safe nurses in the United Kingdom. The authors conclude that the untested educational ideology that brought root and branch change to nurse training in 1983 and which failed to produce nurses ,fit for practice and purpose' may still prevail. Relevance to clinical practice., The present paper demonstrates that United Kingdom nurse training still has no uniform and mandatory system in place to ensure, as far as is possible, that all registered nurses are clinically competent and safe to practice. [source] Considering a multisite study?JOURNAL OF COMMUNITY PSYCHOLOGY, Issue 2 2002How to take the leap, have a soft landing Although most policymakers agree that a fundamental goal of the mental health system is to provide integrated community-based services, there is little empirical evidence with which to plan such a system. Studies in the community mental health literature have not used a standard set of evaluation methods. One way of addressing this gap is through a multisite program evaluation in which multiple sites and programs evaluate the same outcomes using the same instruments and time frame. The proposition of introducing the same study design in different settings and programs is deceptively straightforward. The difficulty is not in the conceptualization but in the implementation. This article examines the factors that act as implementation barriers, how are they magnified in a multisite study design, and how they can be successfully addressed. In discussing the issue of study design, this article considers processes used to address six major types of barriers to conducting collaborative studies identified by Lancaster or Lancaster's six Cs,contribution, communication, compatibility, consensus, credit, and commitment. A case study approach is used to examine implementation of a multisite community mental health evaluation of services and supports (case management, self-help initiatives, crisis interventions) represented by six independent evaluations of 15 community health programs. A principal finding was that one of the main vehicles to a successful multisite project is participation. It is only through participation that Lancaster's six Cs can be addressed. Key factors in large, geographically dispersed, and diverse groups include the use of advisory committees, explicit criteria and opportunities for participation, reliance on all modes of communication, and valuing informal interactions. The article concludes that whereas modern technology has assisted in making complicated research designs feasible, the operationalization of timeless virtues such as mutual respect and trust, flexibility, and commitment make them successful. © 2002 John Wiley & Sons, Inc. [source] Improving general practitioner records in France by a two-round medical auditJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2002Jean Brami MD Abstract Rationale, aims and objectives,The effectiveness of clinical audits in changing the practice of health care professionals is a moot point. Methods of implementation impinge directly upon outcomes. We investigated whether a network of local opinion leaders could contribute towards a successful audit. Our objectives were to: (i) bring about an improvement in record keeping in general practice; and (ii) increase GPs' awareness of medical evaluation. Methods,The GPs were recruited by local opinion leaders who had been briefed by the French National Agency for Accreditation and Evaluation in Health Care (ANAES, formerly ANDEM). On a given day (first round of the audit) they were invited to examine whether the medical records of their 10 first patients met 13 set criteria. Overall results were analysed by ANAES. Each GP was informed of how well they had fared compared with the regional and national averages and was provided with a standard set of recommendations. Anonymity was ensured by the local leaders. A second round was conducted 6 months later. Results,A total of 244 GPs took part in both rounds of the audit; 32 dropped out after the first round. Their results were of a significantly lower standard. A significant improvement in results (P < 0.025) was recorded between the two rounds for all 13 criteria of the questionnaire. Overall scores improved between the two rounds for 69% of the GPs and improved above average for 49%. The greatest scatter in results was noted for items relating to medical history rather than to personal identity (administrative data). Conclusions,Self-assessment can help improve general standards of medical record keeping. A network of local opinion leaders, briefed by a national agency whose mission is to promote quality improvement in health care, seems to be an effective means of inducing participation in self-assessment. [source] Sleep architecture in children with adenoidal hypertrophyJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 10 2006Xiao-Wen Zhang Aim: Adenoidal hypertrophy (AH) in children is associated with obstructive manifestations like mouth breathing, snoring. Unfortunately, little is known regarding sleep architecture of AH in children. The purpose of this study was therefore undertaken to investigate the polysomnographic variables in children with AH. Method: 47 children with AH and 11 controls underwent nocturnal polysomnography. Sleep was scored manually according to the standard set by Rechtschaffen. Results: In AH, stage 1 sleep percentage and rapid eye movement (REM) latency were increased significantly, while the sleep percentage of stage 2 and REM was decreased remarkably compared with that of controls. Arousal index in AH was much more higher than that in controls. Arousal index in REM sleep was higher than that in non-rapid eye movement (NREM) sleep in AH, but the number of arousals in REM sleep was lower than that in NREM sleep. Hypopnea events were the most common type of respiratory events, followed by obstructive events in AH and controls. Apnea/hypopnea index in AH was higher in comparison to controls. No significant difference was found between the children with AH and controls in SaO2 nadir (%) and base mean SaO2 (%). Apnea/hypopnea index was related to hypopnea arousal in REM sleep and hypoxemia arousal in NREM sleep. Conclusion: AH is predominantly characterised by a hypopnea with little obstruction in children. Our results clearly and for the first time demonstrated that sleep architecture was abnormal in children with AH. We therefore speculate that hypopnea arousal in REM sleep and hypoxemia arousal in NREM sleep may play an important role in the course of respiratory disturbance. [source] Prenatal protein malnourished rats show changes in sleep/wake behavior as adultsJOURNAL OF SLEEP RESEARCH, Issue 1 2000Subimal Datta SUMMARY Prenatal protein malnutrition significantly elevates brain levels of serotonin in rats, and these levels remain elevated throughout their lives. This biogenic amine is involved in the regulation of many physiological functions, including the normal sleep/wake cycle. The present study examined the effects of prenatal protein malnutrition on the sleep/wake cycle of freely moving adult rats. Six prenatally protein malnourished (6% casein) and 10 well-nourished (25% casein) male rats (90,120-day-old) were chronically implanted with a standard set of electrodes (to record cortical electroencephalogram, neck muscle electromyogram, electrooculogram, and hippocampal theta wave) to objectively measure states of sleep and wakefulness. Six-hour polygraphic recordings were made between 10.00 and 16.00 h; a time when the rats normally sleep. Prenatally malnourished rats spent 20% more time in slow wave sleep (SWS) compared to the well-nourished rats. The total percentage of time spent in rapid eye movement (REM) sleep was 61% less in prenatally malnourished rats compared to well-nourished control rats. These findings demonstrate the adverse consequences of prenatal protein malnutrition on the quality and quantity of adult sleep in rats. These sleep changes are potentially detrimental to normal social behavior and cognitive functions. Prenatally malnourished rats are an excellent animal model to study the role of endogenous serotonin in the regulation of the normal sleep/wake cycle. [source] Institutional Trust and Subjective Well-Being across the EUKYKLOS INTERNATIONAL REVIEW OF SOCIAL SCIENCES, Issue 1 2006John Hudson SUMMARY This paper analyzes the impact of institutions upon happiness through their intermediary impact upon individual trust. The empirical work is based on Eurobarometer data covering the 15 countries of the EU prior to its expansion in 2004. With respect to trust, we present evidence that, although it is endogenous with respect to the performance of the institution, changes in the individual's personal circumstances can also have an impact, indicating that trust is not simply learned at an early age. Hence unemployed people tend to have lower levels of trust not only in the main economic institutions , government and the Central Bank , but in other state institutions too such as the police and the law. Trust also differs in a systematic manner with respect to education and household income, increases (decreases) in either increase (decrease) trust in most institutions. If we assume that more educated people make better judgments, this suggests that on average people tend to have too little trust in institutions. However, it is also possible that both of these variables impact on the interaction between institutions such as the police and other government agencies and the citizen, with prosperous, well educated people being at an advantage and possibly able to command more respect. Age too impacts on institutional trust. For the UN, the unions, big business, voluntary organizations and the EU, trust first declines and then increases with the estimated turning points ranging between 44 and 56 years. For most other organizations trust significantly increases with age. Turning to subjective well-being, we find the standard set of socio-economic variables to be significant. But the focus here is on the impact of institutional trust. We find that trust (mistrust) in the European Central Bank, the EU, national government, the law and the UN all impact positively (negatively) on well-being. Hence overall our results support the conclusion that happiness does not solely lie within the realm of the individual, but that institutional performance also has a direct impact upon subjective well-being. [source] Efficacy of topical PUVA soaks for palmoplantar dermatoses: an auditPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 6 2008Donal O'Kane Background: With a lack of evidence base for individual topical PUVA protocols, treatment is presently based on the consensus of current practice. This audit was designed to investigate the effectiveness of topical PUVA for palmoplantar dermatoses. Methods: Phototherapy notes were reviewed on all patients who received hand and/or foot PUVA 2002,2007 in the Northern Health and Social Care Trust (NHSCT), Northern Ireland. Results: Thirty patients met the inclusion criteria for the study. The mean number of treatments, maximum single UVA dose, and cumulative dose, were 18.4, 4.2 J/cm2, and 48.3 J/cm2, respectively. A positive response to treatment occurred in 51.3% of patients, which fell short of the 70% standard set. In a multivariate logistic regression analysis, number of treatments (P=0.04) and maximum single UVA dose (P=0.03) were the only variables associated with positive treatment outcome. The response was not influenced significantly by skin type, concurrent topical treatments, or cumulative UVA dose. Limitations to the study: Small patient numbers may have prevented the statistical significance of individual variables. Conclusions: UV dose increments should be clearly defined to avoid excess caution at the expense of an adequate patient response, and a minimum of 20 treatments administered to all patients, if tolerated. [source] Audit of time taken to heal diabetic foot ulcersPRACTICAL DIABETES INTERNATIONAL (INCORPORATING CARDIABETES), Issue 1 2001DPodM, Linda Robertshaw BSc (Hons), SRCh Senior I Podiatrist Abstract Since the Newcastle Diabetes Centre opened in 1997, the three podiatrists working in the centre have established specialised ulcer clinics to see patients with foot ulcers at least twice per week. As this was a new service, a baseline audit was proposed to provide a level with which to compare future developments. The standard was set at 80% of diabetic foot ulcers to be healed within six months of referral to the podiatry team. All patients with diabetes presenting at the Podiatry Department, Newcastle Diabetes Centre, with a new foot ulcer during the period from 1 December 1997 to 31 May 1998 were entered into the audit. The ulcers were then monitored for up to six months until the end of the audit period on 30 November 1998. The result was that 85% of diabetic foot ulcers healed within six months, which exceeds the standard set at 80%. The average time taken to heal diabetic foot ulcers was eight weeks. Copyright © 2001 John Wiley & Sons, Ltd. [source] Some fundamental aspects of building protein structures from fragment librariesPROTEIN SCIENCE, Issue 6 2004J. Bradley Holmes Abstract We have investigated some of the basic principles that influence generation of protein structures using a fragment-based, random insertion method. We tested buildup methods and fragment library quality for accuracy in constructing a set of known structures. The parameters most influential in the construction procedure are bond and torsion angles with minor inaccuracies in bond angles alone causing >6 Å C,RMSD for a 150-residue protein. Idealization to a standard set of values corrects this problem, but changes the torsion angles and does not work for every structure. Alternatively, we found using Cartesian coordinates instead of torsion angles did not reduce performance and can potentially increase speed and accuracy. Under conditions simulating ab initio structure prediction, fragment library quality can be suboptimal and still produce near-native structures. Using various clustering criteria, we created a number of libraries and used them to predict a set of native structures based on nonnative fragments. Local C,RMSD fit of fragments, library size, and takeoff/landing angle criteria weakly influence the accuracy of the models. Based on a fragment's minimal perturbation upon insertion into a known structure, a seminative fragment library was created that produced more accurate structures with fragments that were less similar to native fragments than the other sets. These results suggest that fragments need only contain native-like subsections, which when correctly overlapped, can recreate a native-like model. For fragment-based, random insertion methods used in protein structure prediction and design, our findings help to define the parameters this method needs to generate near-native structures. [source] Educational Standards in Private and Public Schools,THE ECONOMIC JOURNAL, Issue 533 2008Giorgio Brunello When school quality increases with the educational standard set by schools, education before college need not be a hierarchy with private schools offering better quality than public schools. In our model, private schools can offer a lower educational standard at a positive price because they attract students with a relatively high cost of effort, who would find the high standards of public schools excessively demanding. We estimate the key parameters of the model and show that majority voting supports a system where private schools have higher quality in the US and public schools have higher quality in Italy. [source] An inherently mass-conserving iterative semi-implicit semi-Lagrangian discretization of the non-hydrostatic vertical-slice equationsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 648 2010Thomas Melvin Abstract Recently an inherently mass-conserving semi-Lagrangian transport scheme has been successfully coupled to an iterative semi-implicit scheme in a global shallow-water-equation (SWE) model. Here that methodology is extended and applied to an iterative semi-implicit semi-Lagrangian (SISL) compressible, non-hydrostatic vertical-slice model, in which the constant reference state of the SWE model is now replaced by a vertically varying reference state. An advantage of this approach is that it preserves the same basic structure as the interpolating, non-mass-conserving, iterative SISL model. The resulting mass-conserving model is applied to a standard set of test problems for such models and compared with results from both the literature and the interpolating, iterative SISL version of the model. © Crown Copyright 2010. Reproduced with the permission of HMSO. Published by John Wiley & Sons, Ltd. [source] Prehospital airway management in Ambulance Services in the United Kingdom,ANAESTHESIA, Issue 11 2004S. Ridgway Summary A postal survey of the 38 Ambulance Services in the United Kingdom was undertaken to find out what equipment is provided for paramedic crews to aid tracheal intubation and to confirm tracheal placement. The response rate to our survey was 100%. Fourteen (37%) ambulance services provided neither stylet nor bougie to facilitate difficult intubation. The laryngeal mask airway was available to 15 (40%) ambulance services. Seventeen (45%) ambulance services had use of a needle cricothyroidotomy set. Twenty-nine (76%) ambulance services had no type of device other than a stethoscope to confirm tracheal tube placement. This survey showed wide variations in the equipment for airway management available to paramedic crews in the United Kingdom. We recommend provision of a standard set of airway management equipment to all paramedic crews in the United Kingdom together with introduction of appropriate training programmes. [source] A standard panel of microsatellites for Asian seabass (Lates calcarifer)ANIMAL GENETICS, Issue 2 2010Z. Y. Zhu Summary Microsatellites are the most popular markers for parentage assignment and population genetic studies. To meet the demand for international comparability for genetic studies of Asian seabass, a standard panel of 28 microsatellites has been selected and characterized using the DNA of 24 individuals from Thailand, Malaysia, Indonesia and Australia. The average allele number of these markers was 10.82 ± 0.71 (range: 6,19), and the expected heterozygosity averaged 0.76 ± 0.02 (range: 0.63,1.00). All microsatellites showed Mendelian inheritance. In addition, eight standard size controls have been developed by cloning a set of microsatellite alleles into a pGEM-T vector to calibrate allele sizes determined by different laboratories, and are available upon request. Seven multiplex PCRs, each amplifying 3,5 markers, were optimized to accurately and rapidly genotype microsatellites. Parentage assignment using 10 microsatellites in two crosses (10 × 10 and 20 × 20) demonstrated a high power of these markers for revealing parent-sibling connections. This standard set of microsatellites will standardize genetic diversity studies of Asian seabass, and the multiplex PCR sets will facilitate parentage assignment. [source] Herbivore feeding preferences in captive and wild populationsAUSTRAL ECOLOGY, Issue 3 2010CHRISTINE M. RAFFERTY Abstract Investigations into the mechanisms underpinning plant selection by herbivores have often yielded conflicting results. Such inconsistency might stem from whether selection experiments are conducted with captive or wild populations, and upon the different measures of plant selection used to determine herbivore preference. Here we compared the feeding preferences of captive and wild kangaroos (Macropus fuliginosus) using a standard set of plant species (14 Hakea spp., Proteaceae) and several measures of herbivore selection to examine how environment influenced relative consumption. Three indices of herbivore consumption were measured: number of plants (NP), total shoot volume per plant (TV) and percentage available shoot volume (PV) consumed. NP and TV were closely correlated in the wild and captive populations and consistently correlated with six morphological and chemical plant attributes examined, the most notable being a strong negative correlation with shoot phenolic content. This uniformity suggests that plant selection by captive kangaroos is broadly consistent with that observed in field trials, and consequently that for macropods, at least, captive trials offer a valid way to determine the relative acceptability of different plant species. However, the fact that our third measure of herbivore selection PV was weakly correlated in captive and wild populations and showed no relationship with shoot phenolic content highlights the importance of which measure of plant selection is applied. We suggest that, while NP and TV are potentially confounded by plant size and availability, they offer the clearest insight into plant selection from the point of view of the herbivore, while PV is more suitable for plant-centred studies. [source] A genetic algorithm for the identification of conformationally invariant regions in protein moleculesACTA CRYSTALLOGRAPHICA SECTION D, Issue 2 2002Thomas R. Schneider Understanding macromolecular function often relies on the comparison of different structural models of a molecule. In such a comparative analysis, the identification of the part of the molecule that is conformationally invariant with respect to a set of conformers is a critical step, as the corresponding subset of atoms constitutes the reference for subsequent analysis for example by least-squares superposition. A method is presented that categorizes atoms in a molecule as either conformationally invariant or flexible by automatic analysis of an ensemble of conformers (e.g. crystal structures from different crystal forms or molecules related by non-crystallographic symmetry). Different levels of coordinate precision, both for different models and for individual atoms, are taken explicitly into account via a modified form of Cruickshank's DPI [Cruickshank (1999), Acta Cryst. D55, 583,601] and are propagated into error-scaled difference distance matrices [Schneider (2000), Acta Cryst. D56, 715,721]. All pairwise error-scaled difference distance matrices are then analysed simultaneously using a genetic algorithm. The algorithm has been tested on several well known examples and has been found to converge rapidly to reasonable results using a standard set of parameters. In addition to the description of the algorithm, a criterion is suggested for testing the identity of two three-dimensional models within experimental error without any explicit superposition. [source] Evaluating combined land conservation benefits from perennial pasture: lucerne (Medicago sativa L.) for management of dryland salinity and herbicide resistance in Western Australia,AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 2 2009Graeme J. Doole The inclusion of perennial pasture phases in cropping rotations has been widely promoted throughout Australia for reducing the incidence of dryland salinity. To a lesser extent, they have also been promoted to enhance the management of herbicide-resistant weeds. No previous economic analysis of perennial pasture has considered both of these benefits. This study combines a dynamic linear programming model to estimate the magnitude of salinity-related benefits and a complex simulation model to assess the economics of herbicide-resistance management. We present a case study of the perennial pasture lucerne (Medicago sativa L.) in the Wheatbelt of Western Australia, where the weed annual ryegrass (Lolium rigidum Gaudin) is resistant to multiple herbicide groups. Sequences incorporating lucerne are the most profitable land use at the standard set of parameter values if (i) annual ryegrass is resistant to all selective herbicides, (ii) the water table is so shallow (approximately < 3.5 m deep) that frequent rotation with perennials is required to avert soil salinisation, (iii) sheep production is highly profitable, or (iv) there is a combination of less extreme cases. The value of perennial pasture is sufficient under these circumstances to overcome its high establishment cost and the displacement of multiple years of crop. Consideration of dryland salinity and herbicide resistance are about equally important in evaluating the economics of lucerne; neither should be neglected. [source] | ||||||||||||||||||||||