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Selected Abstracts4263: Observation in choroidal melanomasACTA OPHTHALMOLOGICA, Issue 2010C GARCIA-ALVAREZ Purpose The management of suspected small choroidal melanomas is controversial. The purpose of the present study is to assess tumor growth, visual acuity changes, activity factors and survival on choroidal melanoma patients under observation in our Intraocular Tumors Unit. Methods Prospective, consecutive and non-interventional case series. Patients diagnosed with choroidal melanoma from 1990 to 2010 and with observation as therapeutic option were included. Criteria for observation were small size without risk factors for growing; medium and large size: no risk factors for growing (but size), advanced age, bad general health, only eye or treatment rejection. Demographic, tumoral and follow-up data were collected in a data base and analyzed. Results 118 out of 397 patients (29.7%) diagnosed with uveal melanoma were enrolled, with mean age of 66.4 years (SD 14.3). The mean follow-up time was 51.1 months (SD 4.5). Regarding the size, 91 (77.1%) tumors were small and 85 (72.%) were diagnosed in a routine examination. Main reason for observation was tumor small/inactive (80,5%) followed by treatment rejection (17.7%). Mean height was 2.8mm (SD 1.9) and mean base 7.6 (SD 2.8). Along the follow-up, 17 tumors grew; 11 were treated with brachytherapy, 5 with enucleation and one with brachytherapy and enucleation. Only 16 patients died during the follow-up, 2 by melanoma metastasis. Conclusion In our series with more than 4 years of follow up, observation seems to be a safe therapeutic option for selected small choroidal melanomas, allowing the patients to preserve visual function. [source] The Nurse Educator's clinical roleJOURNAL OF ADVANCED NURSING, Issue 1 2005Odette Griscti MHSc RN Aim., This paper reports a two-phase descriptive study exploring the clinical role of the nurse educator in Malta. Background., Previous studies indicate a number of similarities and differences in the clinical role of nurse educators by country of practice. These include importance assigned to the role, factors inhibiting/facilitating the role, means to eliminate barriers to the role, and perceptions of the ideal role. Design and methods., Data were collected using both quantitative and qualitative strategies. The quantitative phase involved asking all educators to fill in a time log of their academic and clinical activities for a 2-week period. In the qualitative phase, the first author interviewed five educators, five nurses and five students about their perceptions of factors which impact the nurse educator's clinical role, as well as what the ideal clinical role of the nurse educator should be. Findings., Maltese nurse educators allot minimal time to their clinical role. Main reasons cited included workload, perceived lack of control over the clinical area, and diminished clinical competence. Nurse educators who frequented the clinical settings (who were either university or joint university and health service employees) where the study took place perceived that employment inequities among the various categories of nurse educators played an important role in the amount of time dedicated by each group to their clinical roles, and the importance individuals in these groups assigned to that role. The majority of interviewees saw the current role of nurse educators in Malta as preparing students for successful completion of the didactic sections of their programme, rather than preparing them with all the knowledge and clinical skills necessary to be competent practitioners. Participants considered that, when in clinical areas, nurse educators did focus on their students, as they should. However, they also thought that they often did not take the opportunity to forge links with professional staff. Conclusion., The clinical role of the Maltese nurse educator needs to be more multifaceted in approach. [source] Pulmonary aspiration of a two-unit bridge during a deep sleepJOURNAL OF ORAL REHABILITATION, Issue 6 2005Ö. K. BA summary, Aspiration of teeth and dental restorations is a recognized, yet an infrequent happening in the literature. Main reasons of aspiration are maxillofacial trauma, dental treatment procedures or ethanol intoxication and dementia. The present case of a 2-unit bridge aspiration is however, not related with any trauma, dental procedure or systemic disease. A 37-year-old male patient had aspirated his bridge while sleeping and the bridge remained unidentified for 1 year despite the radiographic controls. He was then referred to the Chest Diseases Department of School of Medicine, Ege University and the radio-opaque object in the right intermediate bronchus was diagnosed to be an aspirated dental prosthesis. Subsequent to the failure of the rigid bronchoscopy, the patient was referred to the Thoracic Surgery Department and had to be operated for retrieval of the foreign body. [source] Is there a need for autopsies in the management of fungal disease?MYCOSES, Issue 4 2008Manfred Knoke Summary The autopsy rates in Germany became low like in other European, American and Asian countries. Main reasons for this development are the lack of acceptance of autopsy in the society as well as in the medical profession, the introduction of a requirement for consent, unclear legal position, the public health system, pressure of costs and a change in the field of activity in pathology with much more diagnostics of surgical and biopsy material. The autopsy is missing with respect to the reliability of causes of death and morbidity statistics and other epidemiological studies. Published data indicate that up to 20,30% of patients who die in hospitals have important diseases/lesions that remain undetected before death but that are found at autopsy. For infectious diseases, the data are similar. Therefore, a higher incidence of invasive fungal infections was found. Some rare fungal disorders are diagnosed by autopsy. Only exact death statistics makes specific health care possible and is cost saving in a public health system in the long term. Autopsy remains an important tool for quality control in medical diagnostic and therapeutic activity. It is also essential for fundamental medical education and further training. [source] Palliative care in aged care facilities for residents with a non-cancer disease: results of a survey of aged care facilities in South AustraliaAUSTRALASIAN JOURNAL ON AGEING, Issue 2 2005Carol Grbich Objectives:,This study reports the results of a cross-sectional study of residential aged care facilities in South Australia which sought to quantify the extent of specialist palliative care involvement in residential aged care facilities as well as identifying the current need for palliative care. Method:,A questionnaire was completed by 51 Directors of Care from 51 of 90 facilities targeted, representing a response rate of 57% and representing 20% of the total number of South Australian licensed beds. Facilities responding were representative of residential aged care facilities in South Australia for location, type of funding and level of care. Results:,Thirty facilities (59%) used specialist palliative care services during 2001 with the average number of residents consulted being four. There were 627 deaths recorded in the 2785 licensed beds, a death rate of 23%. The majority of these deaths were from non-cancer diseases (83%) and up to two-thirds of all deaths occurred away from low care facilities, usually in an acute care setting. Main reasons for transfer away from the facility were; an acute care episode requiring other expertise, rapid deterioration of the resident, care needs beyond the facility, or the general practitioner or family requested a transfer. Care Directors estimated that 7% of their current residents would be considered palliative and the majority of these had non-cancer diseases (78%). Conclusion:,These findings indicate that palliative care is an important aspect of care in residential aged care facilities for clients with a non-cancer diagnosis. [source] Results from the International Cataract Surgery Outcomes StudyACTA OPHTHALMOLOGICA, Issue thesis2 2007Jens Christian Norregaard MD Abstract It is widely accepted that cataract extraction with intraocular lens implantation is a highly effective and successful procedure. However, quality assessments and studies of effectiveness should still be undertaken. As with any surgical treatment modality, complications may occur, leading to suboptimal outcomes, additional health costs and deterioration in patients' functional capacity. International variation in clinical practice patterns and outcomes can serve as important pointers in the attempt to identify areas amenable to improvements in quality and cost-effectiveness. Once demonstrated, similar clinical results obtained in different health care systems can improve the level of confidence in a clinical standard against which the quality of care can be evaluated. The International Cataract Surgery Outcomes Study was established in 1992. The objective of this international comparative research project was to compare cataract management, outcomes of surgery and quality of care in four international sites. The study was conducted in the 1990s, since when many developments and refinements have emerged within cataract surgery. The actual figures reported in this thesis may no longer be of specific relevance as a decade has passed since their collection. However, the research questions and methods used in the study are still highly important and justify the publication of this report. The report deals with problems related to quality assessment, benchmarking, and the establishment and design of nationwide clinical databases , issues that are currently the focus of much attention. Moreover, the problems related to cross-national comparisons are increasingly relevant as more international databases are established. The study makes suggestions on how to report and compare objective as well as subjective criteria for surgery. The issue of how to report subjective criteria is a particular subject of current discussion. Four sites with high-quality health care systems were examined in this study: the USA, Denmark, the Province of Manitoba (Canada), and Barcelona (Spain). The design of the international research programme was based on methods developed by the US National Cataract Surgery Outcomes Study conducted by the US Cataract Patients Outcomes Research Team. The International Cataract Surgery Outcomes Study comprised three separate studies: a survey of ophthalmologists; a prospective cohort study, and a retrospective register-based cohort study. The survey study was based on data generated by a self-administered questionnaire completed by ophthalmologists in the four study areas. The questionnaire examined routine clinical practice involving patients considered for cataract surgery, and included questions on anaesthesia, monitoring and surgical techniques. The prospective cohort study was a large-scale, longitudinal observational study of patients undergoing first-eye cataract surgery in each study site. Patients were sampled consecutively from multiple clinics and followed for 4 months postoperatively. The retrospective cohort study was based on the Danish National Patient Register and claims data from the USA. This study could not be carried out in Barcelona or Manitoba as no suitable administrative databases were available. The papers based on register databases deal with retinal detachment and endophthalmitis but are not included in this thesis as the material was previously reported in my PhD thesis. The application of the studies was highly co-ordinated among the four sites and similar methods and instruments were used for data collection. The development of the data collection strategy, questionnaires, clinical data forms and data analyses were co-ordinated through weekly telephone conferences, annual in-person conferences, correspondence by mail or fax, and the exchange of sas programs and data files via the Internet. The survey study was based on responses from 1121 ophthalmologists in the four sites and results were presented in two papers. Within the previous year the participating ophthalmologists had performed a total of 212 428 cataract surgeries. With regard to preoperative ophthalmic testing, the present study reveals that refraction, fundus examination and A-scanning were performed routinely by most surgeons in all four sites. Other tests were reported to be performed routinely by some surgeons. It is unclear why any surgeon would use these other tests routinely in cataract patients with no ocular comorbidity. It appears that if this recommendation from the US Clinical Practice Guidelines Panel was broadly accepted, the use of these procedures and costs of care could be reduced, especially in Barcelona, the USA and Canada. Restricted use of medical screening tests was reported in Denmark. If this restricted screening were to be implemented in the USA, Canada and Barcelona, it would have significant resource implications. The most striking finding concerned the difference in monitoring practice between Denmark and each of the other three sites. In Denmark, monitoring equipment is seldom used and only occasionally is an anaesthesiologist present during cataract surgery. By contrast, in the other study sites, the presence of an anaesthesiologist using monitoring equipment is the norm. Adopting the Danish model in other sites would potentially yield significant cost savings. The results represent part of the background data used to inform the decision to conduct the two large-scale, multicentre Studies of Medical Testing for Cataract Surgery. The current study is an example of how surveys of clinical practice can pinpoint topics that need to be examined in randomized clinical trials. For the second study, 1422 patients were followed from prior to surgery until 4 months postoperatively. Preoperatively, a medical history was obtained and an ophthalmic examination of each patient performed. After consent had been obtained, patients were contacted for an in-depth telephone interview. The interview was repeated 4 months postoperatively. The interview included the VF-14, an index of functional impairment in patients with cataract. Perioperative data were available for 1344 patients (95%). The 4-month postoperative interview and clinical examination were completed by 1284 patients (91%). Main reasons for not re-evaluating patients were: surgery was cancelled (3%); refusal to participate (2%); lost to follow-up (1%), and death or being too sick (1%). The results have been presented in several papers, of which four are included in this thesis. One paper compared the preoperative clinical status of patients across the four sites and showed differences in both visual acuity (VA) and VF-14 measures. The VF-14 is a questionnaire scoring disability related to vision. The findings suggest that indications for surgery in comparable patients were similar in the USA and Denmark and were more liberal than in Manitoba and Barcelona. The results highlight the need to control for patient case mix when making comparisons among providers in a clinical database. This information is important when planning national databases that aim to compare quality of care. A feasible method may be to use one of the recently developed systems for case severity grading before cataract surgery. In another paper, perioperative clinical practice and rates of early complications following cataract surgery were compared across the four health care systems. Once again, the importance of controlling for case mix was demonstrated. Significant differences in clinical practice patterns were revealed, suggesting a general trend towards slower diffusion of new medical technology in Europe compared with North America. There were significant differences across sites in rates of intra- and early postoperative events. The most important differences were seen for rates of capsular rupture, hyphaema, corneal oedema and elevated pressure. Rates of these adverse events might potentially be minimized if factors responsible for the observed differences could be identified. Our results point towards the need for further research in this area. In a third paper, 4-month VA outcomes were compared across the four sites. When mean postoperative VA or crude proportions of patients with a visual outcome of <,0.67 were compared across sites, a much poorer outcome was seen in Barcelona. However, higher age, poorer general health status, lower preoperative VA and presence of ocular comorbidity were found to be significant risk factors associated with increased likelihood of poorer postoperative VA. The proportions of patients with these risk factors varied across sites. After controlling for the different distributions of these factors, no significant difference remained across the four sites regarding risk of a poor visual outcome. Once again the importance of controlling for case mix was demonstrated. In the fourth paper, we examined the postoperative VF-14 score as a measure of visual outcomes for cataract surgery in health care settings in four countries. Controlling for case mix was also necessary for this variable. After controlling for patient case mix, the odds for achieving an optimal visual function outcome were similar across the four sites. Age, gender and coexisting ocular pathology were important predictors of visual functional outcome. Despite what seemed to be an optimal surgical outcome, a third of patients still experienced visual disabilities in everyday life. A measure of the VF-14 might help to elucidate this issue, especially in any study evaluating the benefits of cataract surgery in a public health care context. [source] The key role of electrophysiology in the diagnosis of visually impaired childrenACTA OPHTHALMOLOGICA, Issue 6 2006Maria Van Genderen Abstract. Purpose:, To describe the outcome of specialized electrophysiology in visually impaired children. Methods:, We carried out a retrospective evaluation of 340 electrophysiological examinations performed in 298 children over a 3-year period (2001,2003), with regard to demographic data, referral pattern, degree of compliance, and diagnostic results. Electrophysiology was performed without sedation or anaesthesia. In electroretinograms, DTL electrodes were used in combination with online selection of responses. Visual evoked potentials testing was performed with seven active occipital electrodes. Results:, The mean age of the children was 7 ± 5 years; 72 (24%) of the children were mentally as well as visually impaired. Main reasons for referral were suspected posterior segment disease, abnormal visual development, unexplained low vision, high myopia, and suspected albinism. Compliance was good in 302/340 (88%), partial in 24/340 (7%), and absent in 14/340 (4%) of the examinations. Of the 326 successful procedures, 215 (66%) showed abnormal results. Tapetoretinal dystrophy (22%), opticopathy (16%), congenital stationary night blindness (13%), and cone dystrophy (11%) were the most frequently established diagnoses. Albinism was confirmed in 14 of 24 suspected patients; additionally, unsuspected misrouting was found in six. In 26 (9%) of the patients, a previously established diagnosis was changed. Conclusions:, In a specialized setting, electrophysiological examinations can be performed successfully in visually impaired children. The results are essential for the final ophthalmological diagnosis and have important consequences for rehabilitation. [source] Application of High Current and Current Zero Simulations of High-Voltage Circuit BreakersCONTRIBUTIONS TO PLASMA PHYSICS, Issue 10 2006C. M. Franck Abstract This paper reports on the use of computational fluid dynamic (CFD) simulations to predict the interruption behaviour of high-voltage circuit breakers (HV-CB) using the self-blast principle. Two different levels of accuracy of the arc model are proven to be sufficiently accurate for simulating the high-current phase and the period around current zero (CZ). For the high-current phase, a simplified equivalent model of the arc is implemented to predict the pressure build-up, and even more important to accurately trace the hot gas from the arcing zone into the exhausts and the heating volume. A detailed analysis of the gas mixing in the heating volume for different arcing times and current amplitudes showed the optimum geometrical design of the heating volume. For the CZ phase, a more detailed arc model is needed including the effects of ohmic heating, radiative energy transfer, and turbulent cooling fully resolved in space and time. The validation with experiments was done and shows good agreement which justifies the use of the implemented model. With it, scaling laws varying only one parameter at a time (pressure and applied current slope) were derived and confirm previously found empirical laws. This is of particular interest, as it is very difficult to derive such scaling laws from experiments where the scatter is always very large and where it is impossible to vary only one parameter at a time. The influence of the most important geometrical parameters of the nozzle on the interruption performance is shown. In addition to previous experimental indications of this, the simulation reveals that turbulent cooling on the arc edge is the main reason for the difference in interruption performance. Moreover, the exact spatio-temporal build-up of arc resistance and with it the detailed understanding of the arc interruption process is possible and shown here for the first time. These simulations enable us to predict HV-CB performance and to minimise the number of development tests and are routinely used in new development projects. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Why Adopt Codes of Good Governance?CORPORATE GOVERNANCE, Issue 1 2008A Comparison of Institutional, Efficiency Perspectives ABSTRACT Manuscript Type: Empirical Research Question/Issue: Given the global diffusion and the relevance of codes of good governance, the aim of this article is to investigate if the main reason behind their proliferation in civil law countries is: (i) the determination to improve the efficiency of the national governance system; or (ii) the will to "legitimize" domestic companies in the global financial market without radically improving the governance practices. Research Findings/Insights: We collected corporate governance codes developed worldwide at the end of 2005, and classified them according to the country's legal system (common or civil law). Then, we made a comparative analysis of the scope, coverage, and strictness of recommendations of the codes. We tested differences between common law and civil law countries using t-tests and probit models. Our findings suggest that the issuance of codes in civil law countries be prompted more by legitimation reasons than by the determination to improve the governance practices of national companies. Theoretical/Academic Implications: The study contributes to enriching our knowledge on the process of reinvention characterizing the diffusion of new practices. Our results are consistent with a symbolic perspective on corporate governance, and support the view that diffusing practices are usually modified or "reinvented" by adopters. Practitioner/Policy Implications: Our results support the idea that the characteristics of the national corporate governance system and law explain the main differences among the coverage of codes. This conclusion indicates the existence of a strong interplay between hard and soft law. [source] The Global Reporting Initiative and corporate sustainability reporting in Swedish companiesCORPORATE SOCIAL RESPONSIBILITY AND ENVIRONMENTAL MANAGEMENT, Issue 3 2003Carl-Johan Hedberg With empirical evidence from Swedish companies, this paper analyses the phenomenon of corporate sustainability reporting (CSR) in general and the use of CSR guidelines developed by the Global Reporting Initiative (GRI) in particular. The main questions at issue are why companies have chosen to use the GRI guidelines and how this has affected corporate social responsibility and environmental management. From interviews with all Swedish companies that use the guidelines, we have found that companies produce CSRs mainly to seek organizational legitimacy, and that the main reason for use of the GRI guidelines is an expectation of increasing credibility of the CSR, but also that it provides a template for how to design a report. Moreover, we have found that the CSR report and the GRI guidelines are of more help for internal than external communication at this stage of development. It could help corporations to learn about themselves and to see what has actually been done in the organization. In all, the GRI guidelines would have the potential for gaining visibility and control of the triple bottom line on a corporate level, but they are in need of further development, not least in relation to the issue of verification. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment. [source] Ethical problems in cytologyCYTOPATHOLOGY, Issue 1 2004. Znidar Great advances in medical science have raised a number of ethical issues, many of which affect cytopathology. Some of the main issues addressed in this paper relate to the organization of a cytology laboratory: internal and external quality control, adequate staffing levels and staff education, cytopathology reporting format and contents, confidentiality issues, relationship with the clinicians and involvement of cytopathologists in clinical management teams. Quality control has to be provided within cytology departments but external quality assurance is also essential, with national monitoring. New technologies should be used according to the best scientific methods, following cytological analysis. Scientific work in cytology has to respect the general principles of scientific ethics. The patient's interest has to be the main reason for such work. [source] Factors affecting the time of onset of resorption in avulsed and replanted incisor teeth in childrenDENTAL TRAUMATOLOGY, Issue 5 2001M. Donaldson Abstract , Resorption is the main reason for loss of replanted teeth. The outcome examined in this study is the timing of the onset of resorption. The effect of dichotomised dry and wet time intervals as well as the presence of additional crown damage and of contamination were determined. Of 84 replanted teeth, 67.5% developed resorptions. Twenty-eight had detectable additional crown damage with a more rapid onset being seen in these cases (P=0.009). The critical limit for dry time was 15 min (P=0.038) and significant differences persisted for greater limits also. Serial analysis of the association between the time of onset of root resorption and dichotomised wet time variables failed to yield any significant associations. There was visible contamination detected in 32 teeth and these exhibited a more rapid onset of resorption than the other cases (P=0.030). Teeth with inflammatory root resorption (12.8%) had a more rapid onset of resorption than those that developed replacement resorption (54.7%) (P<0.001). It is concluded that the risk of early resorption is increased in teeth that have additional damage or have contamination, or are kept in dry conditions for longer than 15 min. [source] Elites in Local Development in the PhilippinesDEVELOPMENT AND CHANGE, Issue 1 2010Andreas Lange ABSTRACT For many Philippine provinces, decentralization and more autonomous local development planning did not lead to the desired outcomes. This article examines the experiences of the two provinces of Cebu and Leyte. While Cebu became a centre of trade and industry, Leyte is still struggling with its local economy oriented to natural resources. A main reason for the divergent development paths of the two islands can be found in the emergence of different elite structures, which resulted in different path-dependent patterns of economic specialization. Despite this different historical experience, both provinces today suffer from similar institutional infirmities in their planning system for promoting local development. Local planning capacity constraints, such as regional and local co-ordination and co-operation patterns, local finances, human capital and knowledge are analysed. The Cebuano elites used the room for manoeuvre provided by decentralization reforms more successfully than elites in Leyte. This created pockets of efficiency in Cebu leading to more development-friendly investment policies. In order to increase local and regional planning capacity, short-term interventions and policy reforms at the local, regional and national level are discussed. [source] Racial Metaphors: Interpreting Sex and AIDS in AfricaDEVELOPMENT AND CHANGE, Issue 5 2003Eileen Stillwaggon Western preconceptions regarding African sexuality distorted early research on the social context of AIDS in Africa and limited the scope of preventive policies. Key works cited repeatedly in the social science and policy literature constructed a hypersexualized pan,African culture as the main reason for the high prevalence of HIV in sub,Saharan Africa. Africans were portrayed as the social ,Other' in works marked by sweeping generalizations and innuendo, rather than useful comparative data on sexual behaviour. Although biomedical studies demonstrate the role of numerous factors that influence HIV transmission among poor people, a narrowly behavioural explanation dominated the AIDS,in,Africa discourse for over a decade and still circumscribes preventive strategies in Africa and elsewhere. [source] A new dimension in combining data?ACTA ZOOLOGICA, Issue 1 2010The use of morphology, phylogenomic data in metazoan systematics Abstract Giribet, G. 2010. A new dimension in combining data? The use of morphology and phylogenomic data in metazoan systematics. ,Acta Zoologica (Stockholm) 91: 11,19 Animal phylogenies have been traditionally inferred by using the character state information derived from the observation of a diverse array of morphological and anatomical features, but the incorporation of molecular data into the toolkit of phylogenetic characters has shifted drastically the way researchers infer phylogenies. A main reason for this is the ease at which molecular data can be obtained, compared to, e.g., traditional histological and microscopical techniques. Researchers now routinely use genomic data for reconstructing relationships among animal phyla (using whole genomes or Expressed Sequence Tags) but the amount of morphological data available to study the same phylogenetic patterns has not grown accordingly. Given the disparity between the amounts of molecular and morphological data, some authors have questioned entire morphological programs. In this review I discuss issues related to the combinability of genomic and morphological data, the informativeness of each set of characters, and conclude with a discussion of how morphology could be made scalable by utilizing new techniques that allow for non-intrusive examination of large amounts of preserved museum specimens. Morphology should therefore remains a strong field in evolutionary and comparative biology, as it continues to provide information for inferring phylogenetic patterns, is an important complement for the patterns derived from the molecular data, and it is the common nexus that allows studying fossil taxa with large data sets of molecular data. [source] Reflux and pH: ,alkaline' components are not neutralized by gastric pH variationsDISEASES OF THE ESOPHAGUS, Issue 1 2000P. Bechi The ability of the ,alkaline' components of reflux to cause harm in vivo is still open to debate, although these components have been shown in vitro to be capable of damaging the mucosa. The precipitation of bile acids and lysolecithin that occurs at low pH values is the main reason for questioning in vivo mucosal damage. This study was undertaken to determine the composition of gastric aspirates at different original pH values and the degree of solubility of the alkaline components when pH modifications are artificially induced. The samples for chemical analysis were collected from indwelling nasogastric tubes after surgical procedures that did not involve the upper gastrointestinal tract. Bile acid and lysolecithin concentrations were assessed by means of dedicated methods. Thirty-five samples were available for bile acid evaluation and 27 for lysolecithin evaluation. Bile acid and lysolecithin assessments were repeated after pH adjustment at 2, 3.5, 5.5 and 7. For easier assessment of the results, three ranges of the original pH were selected (pH,<,2, 2 , pH < 5, pH , 5). For each pH range, results were pooled together and compared with those in the other pH ranges. Bile acid concentrations were 113 ± 48, 339 ± 90 and 900 ± 303 (mean ± s.e.m. ,mol/L), respectively, in the three groups selected on account of the different original pH values. Differences were significant (p < 0.001). Both taurine- and glycine-conjugated bile acids were represented even at pH < 2. No major differences were observed in bile acid concentration with the artificially induced pH variations. Lysolecithin concentrations were 5.99 ± 3.27, 30.80 ± 8.43 and 108.37 ± 22.17 (mean ± SEM ,g/ml), respectively, in the three groups selected on account of the different original pH ranges. Differences were significant (p < 0.001). No significant differences in lysolecithin concentration were detected with the artificially induced pH variations. In conclusion, both bile acids and lysolecithin are naturally represented in the gastric environment even at very low pH values, although their concentrations decrease on lowering of the naturally occurring pH. Given the concentration variability of bile acids and lysolecithin, further studies are needed to assess the minimal concentration capable of mucosal damage in vivo. [source] Why are ferns regularly over-represented on state and provincial rare plant lists?DIVERSITY AND DISTRIBUTIONS, Issue 6 2006Matthew Wild ABSTRACT Several recent studies have suggested that rare species are not randomly distributed throughout plant taxa. This would appear to apply to North American ferns, which are frequently over-represented on local lists of rare plant species. However, such lists often paint a skewed portrait of the true situation because of our tendency to recognize the rarity of well-known and charismatic species while ignoring that of lesser-known or less-appreciated species. In order to verify if this over-representation of ferns is a real and consistent trend throughout local floras in North America, we used data from what we consider to be the most complete and objective available database: NatureServe Explorer (http://www.natureserve.org/explorer/). We compiled data on total vascular plant species, total fern species, as well as rare vascular plant species and rare fern species for each North American subnational (Canadian province or US state) flora. Rare species were defined as those belonging to one of NatureServe's ,at risk' categories. The null hypothesis that the contribution of rare ferns to total rare species did not differ from their contribution to the total vascular flora was assessed using ,2. Out of 64 subnational floras, we obtained significantly higher values than expected in 28 cases, and significantly lower in only one case. Similar trends hold true for individual fern families. These tendencies could be related to several factors of anthropogenic, biological, climatological, evolutionary, and geographical origin. However, we believe that the main reason is related to scale, namely the geopolitical units at which rarity is often studied. Our results illustrate one of the problems of a parochial approach to conservation, where the perceived rarity of an entire taxon is exaggerated because of the scale at which rarity is addressed. [source] Client satisfaction and risk behaviours of the users of syringe dispensing machines: a pilot studyDRUG AND ALCOHOL REVIEW, Issue 1 2008MD MOFIZUL ISLAM MSc Abstract Introduction and Aims. The study examines risk behaviours of the users of syringe dispensing machines (SDMs) and evaluates the usefulness of these machines in providing injecting drug users (IDUs) with sterile injecting equipment. Design and Methods. Self-administered questionnaires were used among users of SDMs in an Area Health Service of Sydney. Results. The majority of the 167 participants reported being happy with the quality of the SDM services. Problems identified with machines were that they were often broken or jammed (32.8% respondents), not in the right place (21.9%) or require money (16.7%). Just over half (50.9%) of the IDUs use SDMs only from 5 p.m. to 9 a.m., the time when almost all other outlets for accessing sterile injecting equipment remain closed. Relatively young IDUs (age , 30 years) were more likely to prefer SDMs over staffed needle syringe programmes (NSPs) compared with older users (age > 30) and to identify stigma (a desire to hide their identity or not liking the way people treat them at staffed NSPs or chemists) as a main reason for using these machines. Primary users of SDMs do not differ from primary users of NSP/chemists in terms of sharing of needles. Those users who had shared in the last month were nearly four times as likely to have never used condoms in sexual encounters over that period (95% confidence interval: 1.2,14.5). Discussion and Conclusion. SDMs appear to complement other outlets of NSPs. Providing free-of-cost equipment from SDMs should be considered carefully, as needing money to buy equipment was a reason given for sharing of needles by 35% of those who shared. [source] Intraclonal variability in Daphnia acetylcholinesterase activity: The implications for its applicability as a biomarkerENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2003Liane Biehl Printes Abstract The relationship between individual growth and acetylcholinesterase (AChE) activity was evaluated for Daphnia magna. Analysis on the influence of two different culture media on baseline AChE activity was performed with Daphnia similis. The results indicated an inverse relationship between D. magna body length and AChE activity. An increase in total protein, which was not proportional to an increase in the rate of the substrate hydrolysis (, absorbance/min), seems to be the reason for this inverse size versus AChE activity relationship. Therefore, toxicants such as phenobarbital, which affect protein and size but not AChE activity directly, have an overall affect on AChE activity. In contrast, the AChE inhibitor parathion altered AChE activity but not protein. Culture medium also had a significant affect on AChE activity in D. similis. Changes in total protein seem to be the main reason for the variations in baseline AChE activity in Daphnia observed in the different evaluations performed in this work. Therefore, AChE activity in Daphnia must be interpreted carefully, and variations related to changes in total protein must be taken into account when applying this enzyme as a biomarker in biological monitoring. [source] The Multicenter Study of Epilepsy Surgery: Recruitment and Selection for SurgeryEPILEPSIA, Issue 11 2003Anne T. Berg Summary:,Purpose: Multiple studies have examined predictors of seizure outcomes after epilepsy surgery. Most are single-center series with limited sample size. Little information is available about the selection process for surgery and, in particular, the proportion of patients who ultimately have surgery and the characteristics that identify those who do versus those who do not. Such information is necessary for providing the epidemiologic and clinical context in which epilepsy surgery is currently performed in the United States and in other developed countries. Methods: An observational cohort of 565 surgical candidates was prospectively recruited from June 1996 through January 2001 at six Northeastern and one Midwestern surgical centers. Standardized eligibility criteria and protocol for presurgical evaluations were used at all seven sites. Results: Three hundred ninety-six (70%) study subjects had resective surgery. Clinical factors such as a well-localized magnetic resonance imaging (MRI) abnormality and consistently localized EEG findings were most strongly associated with having surgery. Of those who underwent intracranial monitoring (189, 34%), 85% went on to have surgery. Race/ethnicity and marital status were marginally associated with having surgery. Age, education, and employment status were not. Demographic factors had little influence over the surgical decision. More than half of the patients had intractable epilepsy for ,10 years and five or more drugs had failed by the time they initiated their surgical evaluation. During the recruitment period, eight new antiepileptic drugs were approved by the Food and Drug Administration for use in the United States and came into increasing use in this study's surgical candidates. Despite the increased availability of new therapeutic options, the proportion that had surgery each year did not fluctuate significantly from year to year. This suggests that, in this group of patients, the new drugs did not provide a substantial therapeutic benefit. Conclusions: Up to 30% of patients who undergo presurgical evaluations for resective epilepsy surgery ultimately do not have this form of surgery. This is a group whose needs are not currently met by available therapies and procedures. Lack of clear localizing evidence appears to be the main reason for not having surgery. To the extent that these data can address the question, they suggest that repeated attempts to control intractable epilepsy with new drugs will not result in sustained seizure control, and eligible patients will proceed to surgery eventually. This is consistent with recent arguments to consider surgery earlier rather than later in the course of epilepsy. Postsurgical follow-up of this group will permit a detailed analysis of presurgical factors that predict the best and worst seizure outcomes. [source] Reasons for placement and replacement of restorations in student clinics in Manchester and AthensEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2000V. Deligeorgi Data on reasons for the placement and replacement of restorations provide insight into patterns of clinical practice. This study investigated reasons for the provision of restorations in student clinics at the Universities of Manchester and Athens. Using the methods first described by Mjör, data were collected in relation to all initial and replacement restorations placed in adult patients in the main teaching clinics in the 2 schools over a 3-month period. The principal reason for intervention was recorded, according to approved treatment plans. Data were collected on 2620 restorations, 1431 (55%) of which were placed in Manchester. Primary caries was the main reason for the placement of initial restorations: 82% in Athens and 48% in Manchester (p<0.001). The principal reason for restoration replacement was secondary caries, accounting for 54% in Manchester and 33% in Athens (p<0.001). Other differences between the schools, included the ratio of initial placement to replacement restorations (Manchester 1:1.1; Athens 1:0.6: p<0.01) and significantly more 2-surface class II restorations having been placed in Manchester (p<0.001). Class III and IV restorations predominated in Athens. It is concluded, despite the acknowledged limitations of the methods employed, that the patterns of placement and replacement of restorations and the use of materials differ between the dental schools of Manchester and Athens. The differences are considered to relate more to local patterns of dental disease and patient selection for student clinics than to any differences in teaching philosophy. Subsequent studies of the type reported, despite acknowledged limitations would provide insight into the impact on patient care of the teaching of new materials, techniques and treatment philosophies. [source] Study on Crack-like Pores of Al Foams Made via the Powder-Metallurgy Route,ADVANCED ENGINEERING MATERIALS, Issue 1-2 2010Lei Wang Mechanisms for the formation and disappearance of the crack-like pores generated during the early stage of Al foaming are investigated. A model for their disappearance process is proposed for the first time. The stress, perpendicular to the compaction direction in uniaxial cold compaction, is caused by the interaction of the Al powder under a high compaction pressure and is the main reason for the formation of the crack-like pores. The results of the model analysis and theoretical calculations suggest that the pressure difference ,P between the initial, round bubbles and the crack-like pores is the driving force for their disappearance. The rapid reduction of ,P is attributed to the decomposition characteristics of the TiH2 powder. [source] Insights into the structure of plant ,-type phospholipase DFEBS JOURNAL, Issue 10 2007Susanne Stumpe Phospholipases D play an important role in the regulation of cellular processes in plants and mammals. Moreover, they are an essential tool in the synthesis of phospholipids and phospholipid analogs. Knowledge of phospholipase D structures, however, is widely restricted to sequence data. The only known tertiary structure of a microbial phospholipase D cannot be generalized to eukaryotic phospholipases D. In this study, the isoenzyme form of phospholipase D from white cabbage (PLD,2), which is the most widely used plant phospholipase D in biocatalytic applications, has been characterized by small-angle X-ray scattering, UV-absorption, CD and fluorescence spectroscopy to yield the first insights into its secondary and tertiary structure. The structural model derived from small-angle X-ray scattering measurements reveals a barrel-shaped monomer with loosely structured tops. The far-UV CD-spectroscopic data indicate the presence of ,-helical as well as ,-structural elements, with the latter being dominant. The fluorescence and near-UV CD spectra point to tight packing of the aromatic residues in the core of the protein. From the near-UV CD signals and activity data as a function of the calcium ion concentration, two binding events characterized by dissociation constants in the ranges of 0.1 mm and 10,20 mm can be confirmed. The stability of PLD,2 proved to be substantially reduced in the presence of calcium ions, with salt-induced aggregation being the main reason for irreversible inactivation. [source] Some Parameters of Correlated Current and Radiated Field Pulses from Lightning to the Gaisberg TowerIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 1 2010Hannes Pichler Non-member Abstract Simultaneous measurements of lightning current and associated radiated electromagnetic field are of fundamental interest for various applications in lightning research. These data can be used for the evaluation of return stroke (RS) models or to investigate the so-called tower effect when lightning hits an elevated object. In this paper, we show the results of simultaneous measurements of current pulses from lightning strikes on the instrumented Gaisberg tower (Austria) and the correlated vertical E-field components at a distance of 78.8 and 108.7 km, respectively. We have analyzed some main lightning current parameters (peak current Ip, 30,90% rise time TI_30-90, and full width at half maximum TI_FWHM and the time-correlated field waveform parameters (Ep, 30,90% rise time TE_30-90, TE_FWHM, and the peak-to-zero time TE_PTZ. With a geometric mean of TI_FWHM = 19 ,s and Ip = 9.6 kA (N = 73) of the RS current pulses used in this study, those strokes are very similar to the strokes in triggered lightning in Florida and Alabama1. With a TE_PTZ of about 10 µs, the zero-crossing time of the radiated E-fields from the tower strokes are significantly shorter than the typical values of 30 , 40 µs (e.g.2). Correlation between the current and field parameters TI_FWHM versus TE_FWHM and TE_PTZ, respectively, is low (R2 = 0.29 and 0.14). We assume that the relatively short lightning channel in the case of the RSs in object-triggered upward flashes is the main reason for the observed short zero-crossing time. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Services for erectile dysfunction in the UK , a 12-month review of referrals to a west Midlands NHS clinicINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2010G. Hackett Summary Introduction:, Few studies have addressed the health economics of the provision of services for sexual dysfunction within the National Health Service. Aim:, To evaluate the referral patterns, workload and prescribing costs in secondary care resulting from government guidance on erectile dysfunction (ED). Method:, A review of 324 consecutive referral letters to the Good Hope Hospital Erectile Dysfunction Clinic was conducted to assess the purpose of referral. Prescribing data and costs were assessed over the same 2-year period. Results:, Severe distress was the main reason for referral in 54% of referrals. Long term prescribing according to government guidance doubled the cost of care and created an unsustainable increase in clinic and pharmacy workload. Conclusions:, Existing regulations designed to control costs of ED therapy have created health inequalities, waste of resources and have increased the overall cost of care. [source] A survey of specialist paediatric dental services in Sweden: results from 2003, and trends since 1983INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2006G. KLINGBERG Summary. The child population in Sweden has changed dramatically during the last 20 years. Changes have also occurred within the Public Dental Service (PDS), regarding the provision of dental care to children and adolescents. All these changes may affect the referral pattern and provision of specialist dental care for children and adolescents. Objectives., The primary aim of this study was to survey the services provided by specialists in paediatric dentistry in Sweden during 2003. A secondary aim was to compare the results with previous surveys. Methods., A Web-based survey was sent to all 34 specialist paediatric dentistry clinics and was answered by all clinics. Data were compared with results from the surveys performed in 1983, 1989, and 1996. Results., The number of paediatric dentists had been relatively constant over the last 20 years, whereas the number of children referred to paediatric dentists had increased by 28% since 1983. It was estimated that 1·3% of all children in Sweden are treated at a specialist paediatric dental clinic in 2003. Dental treatment need in combination with behaviour management problems (BMP) was the main reason for referral and occurred in 37% of all referrals. The proportion of medically compromised children/children with disabilities had increased from 6% in 1983 to 22% in 2003. The number of patients treated using sedation and general anaesthesia had increased since 1983, and particularly since 1996. Conclusions., Despite improvements in dental health among children and adolescents in Sweden during the last 20 years, an increasing number of children are referred for specialist paediatric dental treatment. There is an urgent need to increase the number of specialist paediatric dentists in Sweden in order to ensure the continuation of high quality of dental care for children and adolescents. [source] The post-amalgam era: a selection of materials and their longevity in the primary and young permanent dentitionsINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2003H. Forss Summary. Objectives. During the last decade there has been a rapid change in the selection of dental restorative materials as the use of amalgam has decreased. The aim of this study was to obtain information on children's restorative dental care in Finland and to analyse the longevity of failed restorations. Design. A random sample of public dental health care centres was drawn from the registers and the dentists working there were asked to record information for each restoration they placed during a three-day period. The survey data comprised a total of 2186 restorations in patients younger than 17 years. Results. Of the children in need of restorative treatment, only a few had previous amalgam restorations. Primary caries was the main reason for restorative treatment in both primary and permanent dentitions (80% and 83%, respectively). In primary teeth, the most common restorative material was resin-modified glass ionomer cement (57·4%), whereas in permanent teeth, composite resin dominated (58·7%). Amalgam was not used at all in the primary dentition and in only 0·6% of permanent teeth. Eighteen per cent of treatments in primary and 12% in permanent teeth were replacements of previous fillings. The mean age of failed glass ionomer restorations was 2·8 years (n = 101) in the primary dentition, and 3·5 years (n = 54) in the permanent dentition. Conclusions. Until better restorative materials are developed, more attention should be paid to the prevention of dental caries as well as to the proper handling of alternative materials. [source] Effects of Interspecific Interactions between Microcystis aeruginosa and Chlorella pyrenoidosa on Their Growth and PhysiologyINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2007Min Zhang Abstract Interactions between Microcystis aeruginosa and Chlorella pyrenoidosa were analyzed by flow cytometry and by phytoplankton pulse-amplitude-modulated fluorimetry (Phyto-PAM) in joint cultures as well as in cultures separated by dialysis membranes. Results showed that the growth of C. pyrenoidosa was greater than that of M. aeruginosa, and that the growth of M.aeruginosa but not the growth of C. pyrenoidosa was significantly inhibited by the interactions between M. aeruginosa and C. pyrenoidosa. Culture filtrates of these two algae showed no apparent effects on the growth of the competing species. For M. aeruginosa, decreases in esterase activity, chlorophyll a fluorescence, and maximum quantum yield were observed in joint cultures, indicating that the metabolic activity and photosynthetic capacity of M.aeruginosa were suppressed. Light limitation from the shading effect of C. pyrenoidosa may be the main reason for such inhibition. For C. pyrenoidosa, esterase activity was suppressed in membrane-separated and joint cultures, suggesting that C.pyrenoidosa was probably affected by allelopathic substances secreted by M.aeruginosa. However, no significant difference was observed in the chlorophyll a fluorescence and maximum quantum yield of C. pyrenoidosa in the two cultures. In addition, interspecific interactions induced a reduction in size in both M. aeruginosa and C.pyrenoidosa, which may contribute to the development of C. pyrenoidosa dominance in the present study. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] FTIR, 1H-NMR spectra, and thermal characterization of water-based polyurethane/acrylic hybridsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008O. R. Pardini Abstract Polyurethane (PU) polymer was synthesized following a prepolymer mixing process, by polyaddition of isophorone diisocyanate (IPDI), poly(propylene glycol) (PPG), 2-hydroxyethyl methacrylate (HEMA), and 2,2-bis(hydroxymethyl)propionic acid (DMPA). The PU anionomer having 2-ethoxymethacrylate terminal groups was dispersed in water by prior neutralization of carboxylic acid groups of DMPA with triethylamine (TEA), chain extended with hydrazine (HZM) in water and a dispersion polymerization with methyl methacrylate/n -butyl acrylate/acrylic acid mixture was performed. The above polymerization reactions lead to the formation of PU/acrylic hybrids having a chemical bond between PU and acrylic moieties. Acrylic content was varied from 0 to 50 wt % and samples were purified to eliminate oligomers and impurities before characterization. The FTIR and 1H-NMR spectra of these purified hybrid samples were obtained and bands and peaks assignments were discussed. Thermal properties (DSC and TGA) were also discussed. Breaking hydrogen bonds is the main reason for changes in properties with increasing acrylic content. Particle size data of dispersions is also presented and discussed. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Hierarchy crystallization structure of a polypropylene random copolymer injection-molded bar induced by a nucleating agentJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2008Yong Wang Abstract In this work, the effect of a nucleating agent on the crystallization structure of an injection-molded bar of a polypropylene random copolymer (PPR) with sorbitol derivatives [1,2,3,4-dibenzylidene sorbitol (DBS)] has been studied. The results show that pure PPR forms a simple skin,core crystallization structure. However, PPR/DBS forms an interesting and complicated hierarchy crystallization structure: there is a transition layer between the skin layer and the core zone. In this transition layer, the crystallization structure consists of some perfect spherulites and many tiny crystallites. Further research suggests that the formation of the hierarchy crystallization structure depends on not only the content of the nucleating agent in the PPR matrix but also the mold temperature during the injection-molding processing. The crystallization behavior of PPR/DBS during the cooling process has been characterized with polarization optical microscopy and differential scanning calorimetry. The results suggest that there are different mechanisms in the crystallization process of PPR/DBS. The formation of a three-dimensional DBS network under a certain condition might be the main reason for the complicated hierarchy crystallization structure. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||