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Practical Value (practical + value)
Selected AbstractsEvaluation Metrics in Classification: A Quantification of Distance-BiasCOMPUTATIONAL INTELLIGENCE, Issue 3 2003Ricardo Vilalta This article provides a characterization of bias for evaluation metrics in classification (e.g., Information Gain, Gini, ,2, etc.). Our characterization provides a uniform representation for all traditional evaluation metrics. Such representation leads naturally to a measure for the distance between the bias of two evaluation metrics. We give a practical value to our measure by observing the distance between the bias of two evaluation metrics and its correlation with differences in predictive accuracy when we compare two versions of the same learning algorithm that differ in the evaluation metric only. Experiments on real-world domains show how the expectations on accuracy differences generated by the distance-bias measure correlate with actual differences when the learning algorithm is simple (e.g., search for the best single feature or the best single rule). The correlation, however, weakens with more complex algorithms (e.g., learning decision trees). Our results show how interaction among learning components is a key factor to understand learning performance. [source] Risk Modeling of Dependence among Project Task DurationsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 6 2007I-Tung Yang The assessments, however, can be strongly influenced by the dependence between task durations. In light of the need to address the dependence, the present study proposes a computer simulation model to incorporate and augment NORTA, a method for multivariate random number generation. The proposed model allows arbitrarily specified marginal distributions for task durations (need not be members of the same distribution family) and any desired correlation structure. This level of flexibility is of great practical value when systematic data is not available and planners have to rely on experts' subjective estimation. The application of the proposed model is demonstrated through scheduling a road pavement project. The proposed model is validated by showing that the sample correlation coefficients between task durations closely match the originally specified ones. Empirical comparisons between the proposed model and two conventional approaches, PERT and conventional simulation (without correlations), are used to illustrate the usefulness of the proposed model. [source] Reassessing the value of nursery areas to shark conservation and managementCONSERVATION LETTERS, Issue 2 2009Michael John Kinney Abstract Concern over declining shark populations has led to an intense interest in their conservation and management. Due to the difficulties involved in managing adult sharks, focus has been placed on young juvenile and neonate age classes that inhabit discrete inshore nursery areas. However, past confusion over what qualifies as a nursery habitat has led to the identification of vast coastal areas as nurseries, making conservation unfeasible. With the establishment of more discerning criteria for nursery area identification such concerns have been somewhat alleviated, but while effort has been put into defining, identifying, mapping, and in some cases protecting nursery areas, little attention has been paid to the practical value of nurseries for the recovery of exploited shark populations. Often neonate and young juveniles are considered the most critical age classes in terms of population stability/recovery, but evidence is mounting that suggests life stages outside the nursery may be more important in this regard. While nursery area protection should remain a component in shark management strategies it will be critical to link early life stage conservation with management strategies that encompass older individuals residing outside nurseries if effective management is to be achieved. [source] The concept of the epilepsy syndrome: How useful is it in clinical practice?EPILEPSIA, Issue 2009Ettore Beghi Summary An epilepsy syndrome is a disorder characterized by a cluster of symptoms and signs customarily occurring in combination. A syndromic approach to the epilepsies would be of practical value for diagnostic, prognostic, and therapeutic purposes. However, despite considerable efforts by leaders in the field of epileptology and the improved knowledge of the clinical, genetic, imaging, and biologic aspects of epilepsy, there are no measurable objective criteria for recognizing seizure types and epilepsy syndromes as separate diagnostic entities with well-defined prognostic and therapeutic aspects. The lack of pragmatic, evidence-based instruments to devise a syndromic classification useful for clinical practice can be explained by the evolving concept of epilepsy syndrome, its dynamic characteristics, the poor prognostic predictivity, and the extremely complex genetic and pathophysiologic mechanisms underlying the epileptic phenomena. In addition, the results of the published reports on epilepsy syndromes are mostly biased by flaws in the study population, design, and statistical analysis. The Classification Core Group of the International League Against Epilepsy (ILAE), which is working on a new classification of the epilepsies, stated that the process of syndrome identification requires that an evidence-based approach be applied to the published literature and future studies. [source] Economic-technological appraisal of grassland resources in Northern China by a fuzzy modelGRASSLAND SCIENCE, Issue 2 2005Hua Wang Abstract After briefly reviewing an appraisal of natural grassland of the Northern China, we made an attempt to apply a new mathematical method to grassland utilization and management. We turned our attention to those factors that can play an important part in an appraisal of grassland resources. A fuzzy mathematical model of multifactorial tri-stage appraisal of grassland resources is proposed in this paper. This is the first report in which such a mathematical model is applied to the appraisal of natural grasslands. To verify the practical value of the model, we appraised three types of grassland as examples and the description of the computing process is given in detail. The present study proves that the model was highly accurate and is suitable for economic-technological appraisals for natural grassland. [source] Optimization of storage conditions for diluted working solutions of porcine factor VIII and performance of the Bethesda assay for the determination of antiporcine FVIII inhibitor titresHAEMOPHILIA, Issue 1 2003R. Winikoff Summary. The use of porcine factor VIII (FVIII) (Hyate:C, Ipsen) has proven to be very successful in treating patients with FVIII inhibitors. The best way to predict the usefulness of porcine FVIII therapy, and/or to estimate the appropriate treatment dose in a given patient, is to measure the patient inhibitor titre against porcine FVIII with the Bethesda assay, using porcine FVIII as the source of FVIII in the assay. The goals of the present study were to (1) find the optimal storage temperature, diluent and concentration for a working solution of porcine FVIII to be used as the source of FVIII for the porcine Bethesda assay, (2) assess the reliability of the labelled FVIII units in the preparation of such working solutions of porcine FVIII and (3) compare the inhibitor titres determined by the Bethesda assay using both porcine and human standard reference curves for measuring residual FVIII. The results of the present study demonstrate that a ready-to-use working solution of 1 U mL,1 of Hyate:C diluted in human FVIII deficient plasma, either containing or deficient in von Willebrand factor antigen, is stable for up to 12 months, at ,20 °C. The preparation of the 1 U mL,1 working solution could be reliably calculated based on the units indicated on the vial label. Finally, using the human standard curve yields similar results to using the porcine standard curve for measuring any titre of allo- or auto-antibody against FVIII in the Bethesda assay, using Hyate:C as the source of FVIII. These findings are of practical value when performing a porcine FVIII-based Bethesda assay. [source] A comparison of donepezil and galantamine in the treatment of cognitive symptoms of Alzheimer's disease: a meta-analysisHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2005Robin D. J. Harry Abstract This review was conducted in order to determine the efficacy of donepezil and galantamine in the treatment of cognitive symptoms of Alzheimer's disease, and also to determine whether galantamine was a superior pharmacological intervention. Meta-analytic methods were used to analyse the data from eight empirical studies which met the inclusion criteria specified. By finding the mean effect sizes of the treatment on the outcome measures of cognition, it was determined that neither drug was greatly efficacious. However, this result does not necessarily diminish the practical value of the drug. It was also found that galantamine was no better than donepezil at treating cognitive decline in AD. Copyright © 2005 John Wiley & Sons, Ltd. [source] Applying Organizational Justice: Questionable Claims and Promising SuggestionsINDUSTRIAL AND ORGANIZATIONAL PSYCHOLOGY, Issue 2 2009JERALD GREENBERG With an eye toward promoting applications of organizational justice, I respond to commentaries on my focal article (Greenberg, 2009a). Specifically, I challenge questionable claims regarding (a) characterization of applied research, (b) why we don't conduct more applied justice research, (c) moral versus instrumental rationales for promoting justice, (d) the validity of intervention studies, and (e) interpretations of Lewin's classic observation about the practical value of theory. I also identify and comment upon two suggestions for promoting applied justice research: (a) promoting cooperation between researchers and practitioners and (b) conducting comprehensive, integrative interventions. [source] Designing predictors for MIMO switching supervisory controlINTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 3 2001Edoardo Mosca Abstract The paper studies the problem of inferring the behaviour of a linear feedback loop made up by an uncertain MIMO plant and a given candidate controller from data taken from the plant possibly driven by a different controller. In such a context, it is shown here that a convenient tool to work with is a quantity called normalized discrepancy. This is a measure of mismatch between the loop made up by the unknown plant in feedback with the candidate controller and the nominal ,tuned-loop' related to the same candidate controller. It is shown that discrepancy can in principle be obtained by resorting to the concept of a virtual reference, and conveniently computed in real time by suitably filtering an output prediction error. The latter result is of relevant practical value for on-line implementation and of paramount importance in switching supervisory control of uncertain plants, particularly in the case of a coarse distribution of candidate models. Copyright © 2001 John Wiley & Sons, Ltd. [source] Gender in elderly suicide: analysis of coroners inquests of 200 cases of elderly suicide in Cheshire 1989,2001INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 12 2003Emad Salib Abstract Objectives The aim of this study is to review gender differences in elderly suicide in relation to specific social aspects of the suicidal process and health care contact before death. Such information may have practical value in identifying and targeting vulnerable elderly in whom suicide may be potentially preventable. Methods Data were extracted from the records of coroner's inquests into all reported suicide of persons aged 60 and over, in Cheshire over a period of 13 years 1989,2001. The Coroner's office covers the whole county of Cheshire (population 1,000,000). Results Men were less likely to have been known to psychiatric services (Odds Ratio [OR] 0.4 95% 0.2,0.6) and with less frequently reported history of previous attempted suicide compared to women (OR 0.5 95% Confidence Intervals [CI] 0.2,1). All deceased from ethnic minorities were men, none of whom had been known to psychiatric services. There was no significant difference between women and men in relation to, physical or psychiatric morbidity, GP contact prior to suicide, intimation of intent or living alone. Of suicide victims not known to services a surprisingly high proportion of 38% and 16% were found to have psychiatric morbidity in men and women respectively. Conclusion Suicide is an important problem in the elderly with gender playing an important part in their social behaviour but a high proportion of the deceased were not known to local services. Primary Care professionals have an important role to play in reducing elderly suicide as most contact with the health service in elderly suicide seem to be with GPs. Copyright © 2003 John Wiley & Sons, Ltd. [source] Distribution of killer cell immunoglobulin-like receptor genes in PolesINTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 4-5 2008E. Majorczyk Summary Killer cell immunoglobulin-like receptors (KIRs) present on natural killer cells and minor subpopulations of T cells recognize class I human leucocyte antigen (HLA) molecules on the surface of target cells. Humans differ by the presence or absence of some KIR genes on their chromosomes. As KIRs are important for the outcome of tissue transplantation (particularly for haematopoietic stem cell transplantation) and possibly for pregnancy and autoimmune diseases, knowledge of the KIR gene distribution in a given human population is of practical value. Therefore, we tested 363 healthy individuals from Western Poland for the presence or absence of KIR genes. Results are compared with those published for other human populations. KIR gene frequencies in Poles are close to these in other Caucasoids but different from those in Asian and African populations, and particularly distant from those in Australian Aborigines. [source] Why Bother With Inter-Regionalism?JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 2 2007Negotiations for a European Union-Mercosur Agreement The article examines why a decade of inter-regional negotiations failed to result in an EU-MERCOSUR agreement, notwithstanding motivating factors at the international, national and societal level. It focuses on inter-regional trade and investment flows to underline the practical value of any agreement, but also considers strategic and ideational issues. [source] Demographic models and the management of endangered species: a case study of the critically endangered Seychelles magpie robinJOURNAL OF APPLIED ECOLOGY, Issue 5 2003Ken Norris Summary 1Demographic models are assuming an important role in management decisions for endangered species. Elasticity analysis and scope for management analysis are two such applications. Elasticity analysis determines the vital rates that have the greatest impact on population growth. Scope for management analysis examines the effects that feasible management might have on vital rates and population growth. Both methods target management in an attempt to maximize population growth. 2The Seychelles magpie robin Copsychus sechellarum is a critically endangered island endemic, the population of which underwent significant growth in the early 1990s following the implementation of a recovery programme. We examined how the formal use of elasticity and scope for management analyses might have shaped management in the recovery programme, and assessed their effectiveness by comparison with the actual population growth achieved. 3The magpie robin population doubled from about 25 birds in 1990 to more than 50 by 1995. A simple two-stage demographic model showed that this growth was driven primarily by a significant increase in the annual survival probability of first-year birds and an increase in the birth rate. Neither the annual survival probability of adults nor the probability of a female breeding at age 1 changed significantly over time. 4Elasticity analysis showed that the annual survival probability of adults had the greatest impact on population growth. There was some scope to use management to increase survival, but because survival rates were already high (> 0·9) this had a negligible effect on population growth. Scope for management analysis showed that significant population growth could have been achieved by targeting management measures at the birth rate and survival probability of first-year birds, although predicted growth rates were lower than those achieved by the recovery programme when all management measures were in place (i.e. 1992,95). 5Synthesis and applications. We argue that scope for management analysis can provide a useful basis for management but will inevitably be limited to some extent by a lack of data, as our study shows. This means that identifying perceived ecological problems and designing management to alleviate them must be an important component of endangered species management. The corollary of this is that it will not be possible or wise to consider only management options for which there is a demonstrable ecological benefit. Given these constraints, we see little role for elasticity analysis because, when data are available, a scope for management analysis will always be of greater practical value and, when data are lacking, precautionary management demands that as many perceived ecological problems as possible are tackled. [source] Seasonal abundance, spatial distribution and sampling indices of thrip populations on cotton; a 4-year survey from central GreeceJOURNAL OF APPLIED ENTOMOLOGY, Issue 7-8 2002P. N. Deligeorgidis Thus, in a cotton field (1.1 ha) in central Greece, 45 leaves were collected (one leaf per cotton plant) at 10-day intervals from May to September, for four consecutive growing seasons (1995,98). Five species of thrips were found: Frankliniella intonsa was the most abundant species followed by Thrips angusticeps, Thrips tabaci, Frankliniella occidentalis and Aeolothrips intermedius. Although considerable differences were observed in the population fluctuations among species, the highest population densities, for all species found, were recorded in July and August. As indicated by Taylor's power law estimates, all species presented aggregated distribution among sampling units. As this type of spatial pattern indicates, the accuracy obtained in estimating mean population density increased with the increase of the mean. Furthermore, the increase of the mean caused an exponential decrease in sample size. However, the precision level is acceptable only in high mean values, while at the same time the benefit from an increase in sample size is of no practical value. [source] Preliminary study of chemical bile duct embolization to treat hepatolithiasis in rabbitsJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 6 2006Fu Yu Li Abstract Background:, The high recurrence rate of hepatolithiasis is still a problem to be solved. The purpose of the present study was therefore to carry out a preliminary study of the practical value of chemical bile duct embolization (CBDE) to treat hepatolithiasis in rabbits. Methods:, Chemical bile duct embolization was performed with phenol or absolute ethanol along with N -butyl-cyanoacrylate. The feasibility and effectiveness of CBDE for chemical hepatectomy was assessed by investigating histological changes, biochemistry for hydroxyproline and in situ hybridization for collagen I. Results:, Histologically, the mucosal epithelia of the embolized bile ducts were entirely replaced by collagen fibers, thus effectively eradicating chronic proliferative cholangitis. Also of note, the diseased biliary duct lumens were completely filled with N -butyl-cyanoacrylate, thus effectively preventing calculus formation. The hepatocytes also disappeared completely in the periphery of the embolized lobe, demonstrating that the desired effects of chemical hepatectomy were achieved through CBDE. In a further comparison of embolizing agents, the phenol-cyanoacrylate embolized livers and bile ducts had a higher level of hydroxyproline and collagen I than those embolized with ethanol plus cyanoacrylate. Conclusion:, Chemical bile duct embolization is a promising approach to prevent the recurrence of hepatolithiasis and to achieve the effect of chemical hepatectomy. [source] Urinary steroids, FSH and CG measurements for monitoring the ovarian cycle and pregnancy in the chimpanzeeJOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2003Keiko Shimizu Abstract: Non-invasive methods for monitoring reproductive status of chimpanzee based on the measurement of urinary steroids and gonadotropins were examined. A typical pre-ovulatory urinary estrone conjugate (E1C) surge and post-ovulatory increase in pregnandiol glucuronide (PdG) were seen during the menstrual cycle. Urinary follicle stimulating hormone (FSH) showed two peaks over the infertile menstrual cycle. The earliest changes indicating pregnancy were a coincident rise in E1C and chorionic gonadotropin (CG) levels and a concomitant fall in FSH levels. Urinary PdG levels showed a prolonged rise. Urinary E1C in the pregnant chimpanzee was higher than during the menstrual cycle and increased with advancing gestation, with maximum levels occurring near term. In the case of stillbirth, E1C and CG levels from mid- through late-pregnancy were low and the prepartum progressive increase in E1C was not shown. The data presented here are of great practical value in captive breeding management of chimpanzees. [source] Attachment, decay, and social networkJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 6 2001Ronald S. Burt To study decay in attachment to an organization, I analyse data on women who obtained an MBA from the University of Chicago's Graduate School of Business (GSB). I measure attachment in terms of network embedding: an alumna is attached to the GSB to the extent that people close to her graduated from the GSB. Behavioral data corroborate the network data in that alumnae measured to be more attached are more likely to have joined an alumni club and made a financial contribution to the school. The hypothesis is that alumnae attachment will decay over time, more slowly when the school is deeply embedded in an alumna's network, more quickly when disruptive events compete for the alumna's time and energy. As expected, attachment declines across the years after graduation (linearly for the first 20 years to about half its initial level), and decay is inhibited when connections with GSB graduates are embedded in stable relations of family, work, or long-term friendship. Decay is remarkably robust to events after graduation (which account for only 2 per cent of explained variance in attachment). In other words, an alumna's attachment today was largely determined while she was in school. The results should be of practical value to people who design programmes to build personal attachment to organizations, and of theoretical interest to scholars who study such connections. Copyright © 2001 John Wiley & Sons, Ltd. [source] Distillation in hollow fibersAICHE JOURNAL, Issue 9 2003Guoliang Zhang Distillation in hollow fibers can give better, more productive separations than distillation in random or structured packing. Since the hollow fibers used have little resistance to mass transfer, the selectivity of the separation depends on the relative volatility, just as in conventional distillation. Because the fibers are nonporous, the distillation can operate at high flows which normally cause flooding, and at low flows which normally compromise loading. As a result, the turndown ratio is nearly infinite and the height of a transfer unit can be as small as desired. Experiments do give values consistent with correlations developed for other membrane modules, although the practical value of hollow fiber distillation is uncertain because of the materials limitations. [source] The effect of the time and mode of application of gibberellic acid and inhibitors of gibberellin biosynthesis on the dormancy of potato tubers grown from true potato seedJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2007Alexios A Alexopoulos Abstract Gibberellic acid (GA3) and inhibitors of gibberellin biosynthesis (daminozide and chlormequat chloride) were applied to the foliage of potato plants grown from true seed (TPS) either once at two stages of plant development, 40 and 60 days after transplantation (DAT), or repeatedly at 10 day intervals starting from the same growth stages. When GA3 was applied towards the end of the vegetative cycle (either singly 60 DAT or repeatedly from the same date), it induced rapid breakage of tuber dormancy, a reduction in specific weight, a higher rate of respiration and increased weight loss during storage. Single applications of GA3 early in the vegetative cycle (40 DAT) had no effect on the weight loss and specific weight of tubers during storage, whereas repeated foliar applications of GA3 starting from the same stage resulted in the formation of tubers with a low specific weight and a high rate of weight loss during storage. However, the tubers from these treatments did not break dormancy uniformly, and, although in the early stages of storage they exhibited a high rate of respiration, this declined to the level of the control (no growth regulator applied). Although daminozide and chlormequat chloride did not affect the duration of tuber dormancy and had little or no effect on any of the other metabolic indicators studied, gibberellin is nevertheless implicated in dormancy breakage, and its application late in the growth cycle may be of practical value in cases where tubers are required for planting soon after harvest. Overall, tubers from TPS respond to plant growth regulator treatment in a similar way to those from plants grown from seed tubers. Copyright © 2007 Society of Chemical Industry [source] A Clinical Index for Disease Activity in Cats with Chronic EnteropathyJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 5 2010A.E. Jergens Background: There is a need for a clinically useful, quantitative index for measurement of disease activity in cats with chronic enteropathy (CE). Objective: To develop a numerical activity index that is of practical value to clinicians treating CE in cats. Animals: Eighty-two cats with CE. Methods: Retrospective case review of 59 cats diagnosed with inflammatory bowel disease (IBD). Prospective validation study of 23 cats having either IBD or food-responsive enteropathy (FRE). Multivariate regression analysis was used to identify which combination of clinical and laboratory variables were best associated with intestinal inflammation of IBD. This combination of variables was expressed in a score that was used as an activity index for the prospective assessment of disease activity and of the effect of treatment in cats with IBD or FRE. Results: The combination of gastrointestinal signs, endoscopic abnormalities, serum total protein, serum alanine transaminase/alkaline phosphatase activity, and serum phosphorous concentration had the best correlation with histopathologic inflammation and comprise the feline chronic enteropathy activity index (FCEAI). Positive treatment responses in cats with CE were accompanied by significant (P < .05) reductions in FCEAI scores after treatment. Conclusions and Clinical Importance: The FCEAI is a simple numerical measure of inflammatory activity in cats with CE. The scoring index can be reliably used in the initial assessment of disease severity for both IBD and FRE and as a measure of clinical response to treatment for these disorders. [source] A new focus on the Walther equation for lubricant viscosity determinationLUBRICATION SCIENCE, Issue 2 2006M. Sánchez-Rubio Abstract Lubricants are widely used in industrial machinery in order to separate solid tribological surfaces and support high loads under severe conditions. In tribological contacts, viscosity plays an important role in the film-forming abilities of the lubricant, but this property is strongly dependent on temperature. Consequently, small variations in temperature cause appreciable variations in the viscosity of lubricating oils. For this reason it is of practical value to be able to predict viscosity changes with temperature. This paper presents a new focus on the Walther equation to determine the viscosity of commercial lubricants at different temperatures. This new approach provides very good correlation with experimental measurements. Copyright © 2006 John Wiley & Sons, Ltd. [source] Chemical ecology of triatomine bugs: vectors of Chagas diseaseMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2001L. Cruz-López Abstract. Knowledge of chemical ecology of haematophagous triatomine bugs (Hemiptera: Heteroptera: Reduviidae) could be of practical value because this polyphyletic subfamily includes species of medical importance, such as vectors of Trypanosoma cruzi Chagas (Kinetoplastida: Trypanosomatidae), the aetiological agent of Chagas disease. For particular species of Dipetalogaster, Panstrongylus, Rhodnius and Triatoma, therefore, we review information on exocrine glands and products, interpreting their apparent roles as semiochemicals in the aggregation, alarm, defence, host-finding and sexual behaviour of these Triatominae. [source] Clinical overview of the synucleinopathiesMOVEMENT DISORDERS, Issue S6 2003Maria J. Martí MD Abstract The term synucleinopathies is used to name a group of neurodegenerative disorders characterized by fibrillary aggregates of ,-synuclein protein in the cytoplasm of selective populations of neurons and glia. These disorders include Parkinson's disease (PD), dementia with Lewy bodies (DLB), pure autonomic failure (PAF), and multiple system atrophy (MSA). Clinically, they are characterized by a chronic and progressive decline in motor, cognitive, behavioural, and autonomic functions, depending on the distribution of the lesions. Because of clinical overlap, differential diagnosis is sometimes very difficult. Parkinsonism is the predominant symptom of PD, but it can be indistinguishable from the parkinsonism of DLB and MSA. Autonomic dysfunction, which is an isolated finding in PAF, may be present in PD and DLB, but is usually more prominent and appears earlier in MSA. DLB could be the same disease as PD but with widespread cortical pathological states, leading to dementia, fluctuating cognition, and the characteristic visual hallucinations. The deposition of aggregates of synuclein in neurons and glia suggests that a common pathogenic mechanism may exist for these disorders. Even though synuclein may play an important role in disease development in these disorders, in light of the different symptom complex and prognosis and management issues that characterize each disorder, we think that the term synucleinopathy has little practical value as a diagnostic term for the clinician. Clinicians should attempt to reach standard clinical diagnosis on patients, such as PD, PAF, or MSA. © 2003 Movement Disorder Society [source] Analysis of bacterial lipodepsipeptides by matrix-assisted laser desorption/ionisation time-of-flight and high-performance liquid chromatography with electrospray mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 8 2001Simona Maria Monti Strains of certain plant pathogenic bacteria, in particular several pathovars of Pseudomonas syringae, are known to produce cyclic lipodepsipeptides (LDPs) endowed with peculiar structural features and noticeable biological activities. In this study, a mass spectrometry procedure is proposed for screening LDP-producing bacterial strains and for identifying and assessing individual LDPs. After matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) screening of thirteen P. syringae strains for LDP production, the extracts from culture filtrates of eight positive strains were subjected to electrospray mass spectrometry for the identification of LDPs. Five strains were found to produce two forms of syringomycins (SR-E and SR-G) and two forms of syringopeptin 25 (SP25A and SP25B); two strains produced SR-E, SR-G and a new form of SP22; one strain produced syringotoxin (ST) and syringostatin A (SS-A) in addition to SP25A and SP25B. The yield in culture of two major LPDs: SR-G (3.2,13.8,mg L,1) and SP25A (41.6,231.5,mg L,1) was assessed by and high-performance liquid chromatography with electrospray mass spectrometry (HPLC/ESI-MS) in both scan and single ion monitoring (SIM) modes. Results of this investigation showed that the mass spectrometry protocol developed here is a precise and reliable method for screening bacterial strains for LDP production and for assessing the amount of each metabolite under various culture conditions. This could be of practical value in view of potential applications, e.g. biocontrol of post-harvest fungal diseases. Copyright © 2001 John Wiley & Sons, Ltd. [source] Science Driven Restoration: A Candle in a Demon Haunted World,Response to Cabin (2007)RESTORATION ECOLOGY, Issue 2 2007Christian P. Giardina Abstract Cabin (2007) asks whether formal science is an effective framework and methodology for designing and implementing ecological restoration programs. He argues that beyond certain ancillary benefits, restoration science has little of practical value to offer the practice of restoration. He goes on to suggest that restoration science most often represents an impediment to restoration practice because an "ivory tower" mentality limits the utility of experiments and diverts research dollars away from answering practical questions. His conclusion is that a nonscientific gardening approach may be more effective at restoring degraded ecosystems. We disagree with this perspective because: (1) restoration science has moved beyond exclusively using "square grids" placed on small patches of land to examine treatment effects on species representation; (2) Cabin's critique greatly undervalues the contribution of science to restoration practice even where the input of restoration scientists is not directly evident; and (3) the practice of restoration is unlikely to advance beyond small-scale and truly haphazard successes without well-designed studies that can provide peer-reviewed and widely accessible published information on the mechanisms underlying both successes and failures. We conclude that through integration with other disciplines, restoration science increasingly will provide novel approaches and tools needed to restore ecosystem composition, structure, and function at stand to landscape scales. As with the broader role of science in the human enterprise (Sagan 1996), the contribution of restoration science to restoration practice can only grow as the discipline matures. [source] Estimation of trade elasticities in the presence of trade barriers, multinationals and imperfect competitionAUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 3 2009Fredoun Z. Ahmadi-Esfahani Recent research highlights the role that multinational trading companies may play in impeding price transmission. In markets characterised by imperfect competition, an estimate of the partial elasticity of demand may be of limited practical value if no account is taken of the reaction of competitors. In this paper, we demonstrate the potential for market structure to affect price transmission and trade elasticities, and challenge the presumption that only government intervention can impact upon price transmission, with examples supporting why theory would suggest otherwise. [source] Evaluation of diagnostic criteria for atopic dermatitis: validity of the criteria of Williams et al. in a hospital-based settingBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2001H. Gu Background Surveys of the prevalence of atopic dermatitis (AD) have been carried out world-wide, but the results vary widely. The differences probably result from the use of different diagnostic criteria. Williams et al. proposed minimum, simplified, diagnostic criteria that require no invasive test and are easy to use. Pilot studies in European countries showed their suitability for implementation both in hospitals and in the community, and their high sensitivity and specificity. Objectives To evaluate the potential practical value of the criteria of Williams et al. in the Chinese population. Methods The criteria of Hanifin and Rajka (gold standard), Williams et al. and Kang and Tian were applied and compared in 111 patients with AD and 121 control subjects with other skin diseases in three out-patient centres in China. Results The criteria of Williams et al. showed a similar diagnostic efficiency to that of the gold standard, with the sensitivity, specificity and , value reaching 95·50%, 97·52% and 0·93, respectively. No significant difference was found between the criteria of Williams et al. and those of Kang and Tian (,2 = 0·69, P > 0·05). ,Onset under the age of 2 years', a criterion of Williams et al. could be used in subjects of any age. Conclusions The diagnostic efficiency of the criteria of Williams et al. was basically similar to those of Hanifin and Rajka and of Kang and Tian in our out-patient settings. However, those of Williams et al. were easier to apply and required no invasive tests. [source] Benchmarks and control charts for surgical site infectionsBRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 7 2000T. L. Gustafson Background Although benchmarks and control charts are basic quality improvement tools, few surgeons use them to monitor surgical site infection (SSI). Obstacles to widespread acceptance include: (1) small denominators, (2) complexities of adjusting for patient risk and (3) scepticism about their true purpose (cost cutting, surgical privilege determination or improving outcomes). Methods The application of benchmark charts (using US national SSI rates as limits) and control charts (using facility rates as limits) was studied in 51 hospitals submitting data to the AICE National Database Initiative. SSI rates were risk adjusted by calculating a new statistic, the standardized infection ratio (SIR), based on the risk index suggested by the Centers for Disease Control National Nosocomial Infection Surveillance Study. Fourteen different types of control chart were examined and 115 suspiciously high or low monthly rates were flagged. Participating hospital epidemiologists investigated and classified each flag as ,a real problem' (potentially preventable) or ,not a problem' (beyond the control of personnel at this facility). Results None of the standard, widely recommended, control charts studied showed practical value for identifying either preventable rate increases or outbreaks (clusters due to a single organism). On the other hand, several types of risk-adjusted control chart based on the SIR correctly identified most true opportunities for improvement. Sensitivity, specificity and receiver,operator characteristic (ROC) analysis revealed that the XmR chart of monthly SIRs would be useful in hospitals with smaller surgical volumes (ROC area = 0·732, P = 0·001). For larger hospitals, the most sensitive and robust SIR chart for real-time monitoring of surgical infections was the mXmR chart (ROC area = 0·753, P = 0·0005). © 2000 British Journal of Surgery Society Ltd [source] Distinguishing Parkinson's disease and essential tremor with transcranial sonographyACTA NEUROLOGICA SCANDINAVICA, Issue 1 2009M. Budisic Objectives,,, Until today there is no reliable test that can clearly distinguish Parkinson's disease (PD) from the essential tremor (ET). Our aim was to determine the usefulness of the transcranial sonography (TCS) in the differential diagnosis of the PD and ET as well as the interobserver reliability for this method. Methods,,, Transcranial sonography of substantia nigra and clinical examination were performed on 80 PD patients, 30 ET patients, and 80 matched controls by two independent physicians. Results,,, Bilateral SN hyperechogenicity over the margin of 0.20 cm2 was found in 91% of PD patients, 10% of healthy subjects, and in 13% patients with ET. Interobserver agreement for this method was significant (Student's t -test, P = 1.000). Conclusions,,, Substantia nigra hyperechogenicity on TCS is a highly specific finding of PD, where in healthy individuals or in ET patients, it might correspond to an increased risk of developing PD later in life or might also be because of the impairment of nearby area of nucleus ruber in ET patients, as suggested by positron emission tomography studies. TCS may serve as a practical and sufficiently sensitive neuroimaging tool in PD diagnoses and in distinguishing it from ET; its repeatability and accuracy might add to its practical value. [source] Molecular Characterization of the NCoA-1,STAT,6 InteractionCHEMBIOCHEM, Issue 8 2008Markus Seitz Abstract Many protein,protein interactions involved in cell signalling, cell adhesion and regulation of transcription are mediated by short ,-helical recognition motifs with the sequence Leu-Xaa-Xaa-Leu-Leu (LXXLL, where Xaa is any amino acid). Originally observed in cofactors that interact with hormone-activated nuclear receptors, LXXLL motifs are now known to occur in many transcription factors, including the STAT family, which transmit signals from activated cytokine receptors at the cell surface to target genes in the nucleus. STAT,6 becomes activated in response to IL-4 and IL-13, which regulate immune and anti-inflammatory responses. Structural studies have revealed how an LXXLL motif located in 2.5 turns of an ,-helical peptide derived from STAT,6 provide contacts through the leucine side chains to the coactivator of transcription, NCoA-1. However, since many protein,protein interactions are mediated by LXXLL motifs, it is important to understand how specificity is achieved in this and other signalling pathways. Here, we show that energetically important contacts between STAT,6 and NCoA-1 are made in residues that flank the LXXLL motif, including the underlined residues in the sequence LLPPTEQDLTKLL. We also demonstrate how the affinity for NCoA-1 of peptides derived from this region of STAT,6 can be significantly improved by optimising knobs-into-holes contacts on the surface of the protein. The results provide important new insights into the origins of binding specificity, and might be of practical value in the design of novel small-molecule inhibitors of this important protein,protein interaction. [source] | |||||||||||||||||||||||||||||||||||||