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Critical Evaluation (critical + evaluation)
Selected AbstractsCRITICAL EVALUATION: PATTERNS OF SURGICAL TECHNICAL ERRORANZ JOURNAL OF SURGERY, Issue 8 2008Thomas B Hugh No abstract is available for this article. [source] A Critical Evaluation of Influence of Ethanol and Diet on Salsolinol Enantiomers in Humans and RatsALCOHOLISM, Issue 2 2010Jeongrim Lee Background:, (R/S)-Salsolinol (SAL), a condensation product of dopamine (DA) with acetaldehyde, has been speculated to have a role in the etiology of alcoholism. Earlier studies have shown the presence of SAL in biological fluids and postmortem brains from both alcoholics and nonalcoholics. However, the involvement of SAL in alcoholism has been controversial over several decades, since the reported SAL levels and their changes after ethanol exposure were not consistent, possibly due to inadequate analytical procedures and confounding factors such as diet and genetic predisposition. Using a newly developed mass spectrometric method to analyze SAL stereoisomers, we evaluated the contribution of ethanol, diet, and genetic background to SAL levels as well as its enantiomeric distribution. Methods:, Simultaneous measurement of SAL enantiomers and DA were achieved by high performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS). Plasma samples were collected from human subjects before and after banana (a food rich in SAL) intake, and during ethanol infusion. Rat plasma and brain samples were collected at various time points after the administration of SAL or banana by gavage. The brain parts including nucleus accumbens (NAC) and striatum (STR) were obtained from alcohol-non-preferring (NP) or alcohol-preferring (P) rats as well as P-rats which had a free access to ethanol (P-EtOH). Results:, Plasma SAL levels were increased significantly after banana intake in humans. Consistently, administration of banana to rats also resulted in a drastic increase of plasma SAL levels, whereas brain SAL levels remained unaltered. Acute ethanol infusion did not change SAL levels or R/S ratio in plasma from healthy humans. The levels of both SAL isomers and DA were significantly lower in the NAC of P rats in comparison to NP rats. The SAL levels in NAC of P rats remained unchanged after chronic free-choice ethanol drinking. There were decreasing trends of SAL in STR and DA in both brain regions. No changes in enantiomeric ratio were observed after acute or chronic ethanol exposure. Conclusions:, SAL from dietary sources is the major contributor to plasma SAL levels. No significant changes of SAL plasma levels or enantiomeric distribution after acute or chronic ethanol exposure suggest that SAL may not be a biomarker for ethanol drinking. Significantly lower SAL and DA levels observed in NAC of P rats may be associated with innate alcohol preference. [source] Critical Evaluation of How the Rosgen Classification and Associated "Natural Channel Design" Methods Fail to Integrate and Quantify Fluvial Processes and Channel Response,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 5 2007A. Simon Abstract:, Over the past 10 years the Rosgen classification system and its associated methods of "natural channel design" have become synonymous to some with the term "stream restoration" and the science of fluvial geomorphology. Since the mid 1990s, this classification approach has become widely adopted by governmental agencies, particularly those funding restoration projects. The purposes of this article are to present a critical review, highlight inconsistencies and identify technical problems of Rosgen's "natural channel design" approach to stream restoration. This paper's primary thesis is that alluvial streams are open systems that adjust to altered inputs of energy and materials, and that a form-based system largely ignores this critical component. Problems with the use of the classification are encountered with identifying bankfull dimensions, particularly in incising channels and with the mixing of bed and bank sediment into a single population. Its use for engineering design and restoration may be flawed by ignoring some processes governed by force and resistance, and the imbalance between sediment supply and transporting power in unstable systems. An example of how C5 channels composed of different bank sediments adjust differently and to different equilibrium morphologies in response to an identical disturbance is shown. This contradicts the fundamental underpinning of "natural channel design" and the "reference-reach approach." The Rosgen classification is probably best applied as a communication tool to describe channel form but, in combination with "natural channel design" techniques, are not diagnostic of how to mitigate channel instability or predict equilibrium morphologies. For this, physically based, mechanistic approaches that rely on quantifying the driving and resisting forces that control active processes and ultimate channel morphology are better suited as the physics of erosion, transport, and deposition are the same regardless of the hydro-physiographic province or stream type because of the uniformity of physical laws. [source] Theological Pragmatism: A Critical EvaluationTHE HEYTHROP JOURNAL, Issue 2 2000Mikael Stenmark Theological pragmatists like Daly, Kaufman, McFague and Reuther claim that the God we should believe in and the kind of images we should use to express our religious faith should be evaluated primarily on the basis of the consequences they have for the maintenance of certain political or moral values. These views are presented and critically evaluated. One difficulty is that their pragmatism seems to clash with our intuition and experience that there is no automatic fit between our moral aspirations and political visions, on the one hand, and how the world is actually structured, on the other. Their strong emphasis on political and moral considerations is, therefore, questionable and only plausible under certain specific circumstances. [source] Critical Evaluation: prognosis for patients with chronic low back pain: inception cohort studyANZ JOURNAL OF SURGERY, Issue 6 2010FRACS (Ortho), Ian A. Harris MBBS, MMed (Clin Epid) No abstract is available for this article. [source] Lipase-Catalyzed Acyl Exchange of Soybean Phosphatidylcholine in n -Hexane: A Critical Evaluation of Both Acyl Incorporation and Product RecoveryBIOTECHNOLOGY PROGRESS, Issue 2 2005Anders F. Vikbjerg Lipase-catalyzed acidolysis was examined for the production of structured phospholipids in a hexane system. In a practical operation of the reaction system, the formation of lyso-phospholipids from hydrolysis is often a serious problem, as demonstrated from previous studies. A clear elucidation of the issue and optimization of the system are essential for the practical applications in reality. The effects of enzyme dosage, reaction temperature, solvent amount, reaction time, and substrate ratio were optimized in terms of the acyl incorporation, which led to the products, and lyso-phospholipids formed by hydrolysis, which led to the low yields. The biocatalyst used was the commercial immobilized lipase Lipozyme TL IM and substrates used were phosphatidylcholine (PC) from soybean and caprylic acid. A response surface design was used to evaluate the influence of selected parameters and their relationships on the incorporation of caprylic acid and the corresponding recovery of PC. Incorporation of fatty acids increased with increasing enzyme dosage, reaction temperature, solvent amount, reaction time, and substrate ratio. Enzyme dosage had the most significant effect on the incorporation, followed by reaction time, reaction temperature, solvent amount, and substrate ratio. However the parameters had also a negative influence on the PC recovery. Solvent amount had the most negative effect on recovery, followed by enzyme dosage, temperature, and reaction time. Individually substrate ratio had no significant effect on the PC recovery. Interactions were observed between different parameters. On the basis of the models, the reaction was optimized for the maximum incorporation and maximum PC recovery. With all of the considerations, the optimal conditions are recommended as enzyme dosage 29%, reaction time 50 h, temperature 54 °C, substrate ratio 15 mol/mol caprylic acid/PC, and 5 mL of hexane per 3 g substrate. No additional water is necessary. Under these conditions, an incorporation of caprylic acid up to 46% and recovery of PC up to 60% can be obtained from the prediction. The prediction was confirmed from the verification experiments. [source] Critical evaluation of cognitive dysfunctions as endophenotypes of schizophreniaACTA PSYCHIATRICA SCANDINAVICA, Issue 2 2004S. Kéri Objective:, Cognitive dysfunctions are potential endophenotypes of schizophrenia. The aim of this study was to investigate whether recent evidence indeed suggests that cognitive dysfunctions are potent indicators of specific genetic traits that represent susceptibility for schizophrenia. Method:, Studies including large, well-defined samples and controlled cognitive assessment have been reviewed. Results:, Evidence suggests that schizophrenia patients and their unaffected biological relatives are impaired in several cognitive domains, including working memory, executive functions, sustained attention, verbal episodic memory, processing of visual and auditory stimuli, and smooth pursuit eye movements. However, these impairments are present only in a limited proportion of subjects, showing low specificity and sensitivity and high variability. Linkage with specific genes is weak. Conclusion:, Although some results are promising, at present cognitive dysfunctions cannot be considered as highly sensitive and specific endophenotypes of schizophrenia. [source] Critical evaluation of buffering solutions for pKa determination by capillary electrophoresisELECTROPHORESIS, Issue 13 2008Elisabet Fuguet Abstract The performance of the most common and also some other less common CE buffers has been tested for the pKa determination of several types of compounds (pyridine, amines, and phenols). The selected buffers cover a pH ranging from 3.7 to 11.8. Whereas some buffers, like acetic acid/acetate, BisTrisH+/BisTris, TrisH+/Tris, CHES/CHES,, and CAPS/CAPS, can be used with all type of analytes, others like ammonium/ammonia, butylammonium/butylammonia, ethylammonium/ethylammonia, diethylammonium/diethylammonia, and hydrogenphosphate/phosphate are not recommended because they interact with a wide range of compounds. The rest of the tested buffers (dihydrogenphosphate/hydrogenphosphate, MES/MES,, HEPES/HEPES,, and boric acid/borate) can show specific interactions depending on the nature of the analytes, and their use in some applications should be restricted. [source] Medical management of left-sided ulcerative colitis and ulcerative proctitis: Critical evaluation of therapeutic trialsINFLAMMATORY BOWEL DISEASES, Issue 10 2006Miguel Regueiro MD Abstract Background: The goal of this work was to critically evaluate the published studies on the treatment of ulcerative proctitis (UP) and left-sided ulcerative colitis (L-UC). The results of this review provided the content for the accompanying treatment guidelines, Clinical Guidelines for the Medical Management of Left-sided Ulcerative Colitis and Ulcerative Proctitis: Summary Statement. Methods: All English language articles published between 1995 and September 2005 were identified through a comprehensive literature search using OVID and PubMed. The quality of the data supporting or rejecting the use of specific therapies was categorized by a data quality grading scale. An "A+" grade was assigned to treatment supported by multiple high-quality randomized controlled trials with consistent results, whereas a "D" grade was given to therapy supported only by expert opinion. The therapeutic efficacy of a treatment was defined by its success in treating UP and L-UC compared with placebo. A medication was ranked as "excellent" if it was specifically studied for UP and L-UC and had consistently positive results compared with placebo or another agent. Quality and efficacy scores were agreed on by author consensus. Results: For the acute treatment of UP or L-UC, the rectally administered corticosteroids and mesalazine (5-ASA), either alone or in combination with oral 5-ASAs, are the most effective therapy: evidence quality, A+; efficacy, excellent. Only rectally administered 5-ASA received an A+/excellent rating for maintenance of remission. Infliximab received an A+ grade for induction and maintenance of remission but only a "good" rating because the studies were performed in all UC, not specifically UP or L-UC. Conclusions: This critical evaluation of treatment provides a "report card" on medications available for the management of patients with UP and L-UC. The guidelines should provide a useful reference and supplement for physicians treating UC patients. [source] Critical evaluation of CFD codes for interfacial simulation of bubble-train flow in a narrow channelINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 6 2007Furkan Özkan Abstract Computational fluid dynamics (CFD) codes that are able to describe in detail the dynamic evolution of the deformable interface in gas,liquid or liquid,liquid flows may be a valuable tool to explore the potential of multi-fluid flow in narrow channels for process intensification. In the present paper, a computational exercise for co-current bubble-train flow in a square vertical mini-channel is performed to investigate the performance of well-known CFD codes for this type of flows. The computations are based on the volume-of-fluid method (VOF) where the transport equation for the liquid volumetric fraction is solved either by the methods involving a geometrical reconstruction of the interface or by the methods that use higher-order difference schemes instead. The codes contributing to the present code-to-code comparison are an in-house code and the commercial CFD packages CFX, FLUENT and STAR-CD. Results are presented for two basic cases. In the first one, the flow is driven by buoyancy only, while in the second case the flow is additionally forced by an external pressure gradient. The results of the code-to-code comparison show that only the VOF method with interface reconstruction leads to physically sound and consistent results, whereas the use of difference schemes for the volume fraction equation shows some deficiencies. Copyright © 2007 John Wiley & Sons, Ltd. [source] Critical evaluation of the use of research tools in evaluating quality of life for people with schizophreniaINTERNATIONAL JOURNAL OF MENTAL HEALTH NURSING, Issue 1 2007Jeanette Hewitt ABSTRACT:, Schizophrenia may lead to impairments in many aspects of life, including physical, cognitive, and role functioning. The subjective quality of life of people with schizophrenia has been shown to be lower than in the general population and appropriate patient-assessed health outcome measures are necessary to capture the distress and disability experienced by people living with a serious mental illness. Although psychiatry has been slow to become involved in quality of life measurement, the use of quality of life instruments has now been recognized as a means of evaluating the outcome of care interventions, in terms of symptoms and functioning. This paper evaluates the effectiveness of two widely used instruments: The Medical Outcomes Study Short Form Health Survey (SF-36) and The Lancashire Quality of Life Profile (LQoLP) in terms of reliability and validity in measuring the quality of life of people with schizophrenia. The LQoLP appeared to be best suited for evaluation of care programmes, whereas the SF-36 was more appropriate for medical trials, comparisons between patient groups, and assessment of the direct consequences of treatment on health and function. Subjective quality of life should, however, be considered to be distinct from clinical status and quality of life assessment should include the broadest range of indicators, to reflect the holistic ethos of mental health nursing. [source] Critical evaluation of the chemical standardization procedure for measuring gastric emptying of solidsJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2002P. Goethals Abstract The purpose of this study was to evaluate the baking process of yolk spiked with octanoate to measure gastric emptying rate of solids. [1- 11C]octanoate was produced by the reaction of [11C]CO2 with heptyl magnesium bromide in tetrahydrofuran (THF), followed by purification with HPLC. The decay corrected radiochemical yield ranged from 24 to 38% (5.9,9.8 GBq EOS, synthesis time: 25 min; specific radioactivity ,90 GBq ,mol,1). To check the evaporation of [1- 11C]octanoate during the baking process of yolk, [1- 11C]octanoate or potassium [1- 11C]octanoate, respectively, was added. An important fraction of the acid evaporated while for the potassium [1- 11C]octanoate <10% disappeared. Conclusion: potassium (1- 13C)octanoate is a better tracer than (1- 13C) octanoate to study gastroenterological phenomena. Copyright © 2002 John Wiley & Sons, Ltd. [source] Quantitative analysis of spatial proteoglycan content in articular cartilage with Fourier transform infrared imaging spectroscopy: Critical evaluation of analysis methods and specificity of the parametersMICROSCOPY RESEARCH AND TECHNIQUE, Issue 5 2010L. Rieppo Abstract Objective: To evaluate the specificity of the current Fourier transform infrared imaging spectroscopy (FT-IRIS) methods for the determination of depthwise proteoglycan (PG) content in articular cartilage (AC). In addition, curve fitting was applied to study whether the specificity of FT-IRIS parameters for PG determination could be improved. Methods: Two sample groups from the steer AC were prepared for the study (n = 8 samples/group). In the first group, chondroitinase ABC enzyme was used to degrade the PGs from the superficial cartilage, while the samples in the second group served as the controls. Samples were examined with FT-IRIS and analyzed using previously reported direct absorption spectrum techniques and multivariate methods and, in comparison, by curve fitting. Safranin O-stained sections were measured with digital densitometry to obtain a reference for depthwise PG distribution. Results: Carbohydrate region-based absorption spectrum methods showed a statistically weaker correlation with the PG reference distributions than the results of the curve fitting (subpeak located approximately at 1,060 cm,1). Furthermore, the shape of the depthwise profiles obtained using the curve fitting was more similar to the reference profiles than with the direct absorption spectrum analysis. Conclusions: Results suggest that the current FT-IRIS methods for PG analysis lack the specificity for quantitative measurement of PGs in AC. The curve fitting approach demonstrated that it is possible to improve the specificity of the PG analysis. However, the findings of the present study suggest that further development of the FT-IRIS analysis techniques is still needed. Microsc. Res. Tech. 2010. © 2009 Wiley-Liss, Inc. [source] Critical evaluation of prognostic factors in childhood asthmaPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 2 2002H. P. Van Bever Current knowledge of the natural history of asthma is improving through the establishment of a more precise definition of asthma linked with information from a number of large-scale longitudinal studies. Risk factors for the development of childhood asthma are now more clearly understood. They include gender, atopic status, genetic and familial factors, respiratory infections, and outdoor and indoor pollution (1). In the present review two types of asthma and their prognosis will be discussed: 1Asthma in preschool children and its risk factors for evolution towards persistent childhood asthma. 2Asthma in older children and its risk factors for evolution towards adult asthma. [source] Critical evaluation of the Braak staging scheme for Parkinson's diseaseANNALS OF NEUROLOGY, Issue 4 2010Kurt A. Jellinger MD No abstract is available for this article. [source] Critical evaluation: what makes a competent surgeon?ANZ JOURNAL OF SURGERY, Issue 9 2010FRACS, Jeffrey M. Hamdorf MB BS No abstract is available for this article. [source] Critical evaluation: perioperative intravenous glutamine supplementationANZ JOURNAL OF SURGERY, Issue 7-8 2010FRACS, Ross C. Smith MD No abstract is available for this article. [source] Critical evaluation: sliding hip screw or Gamma nail for hip fractures?ANZ JOURNAL OF SURGERY, Issue 11 2009Appraisal of a Cochrane review No abstract is available for this article. [source] Critical evaluation: review of the SAPPHIRE trial and the role of stenting in carotid stenosisANZ JOURNAL OF SURGERY, Issue 1-2 2009Yi-Yi Chen First page of article [source] Critical evaluation of the different staging systems for hepatocellular carcinoma (Br J Surg 2004; 91: 400-408)BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 8 2004Jean-Nicolas Vauthey The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk. Copyright © 2004 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source] Critical evaluation of the methodology employed in cognitive development trialsACTA PAEDIATRICA, Issue 2003P Burgard First page of article [source] Critical evaluations in the ANZ Journal of SurgeryANZ JOURNAL OF SURGERY, Issue 10 2009John C. Hall Editor-in-Chief No abstract is available for this article. [source] Genetic Data and the Listing of Species Under the U.S. Endangered Species ActCONSERVATION BIOLOGY, Issue 5 2007SYLVIA M. FALLON Acta de Especies en Peligro de E. U. A.; decisiones de enlistado; segmento poblacional distinto Abstract:,Genetic information is becoming an influential factor in determining whether species, subspecies, and distinct population segments qualify for protection under the U.S. Endangered Species Act. Nevertheless, there are currently no standards or guidelines that define how genetic information should be used by the federal agencies that administer the act. I examined listing decisions made over a 10-year period (February 1996,February 2006) that relied on genetic information. There was wide variation in the genetic data used to inform listing decisions in terms of which genomes (mitochondrial vs. nuclear) were sampled and the number of markers (or genetic techniques) and loci evaluated. In general, whether the federal agencies identified genetic distinctions between putative taxonomic units or populations depended on the type and amount of genetic data. Studies that relied on multiple genetic markers were more likely to detect distinctions, and those organisms were more likely to receive protection than studies that relied on a single genetic marker. Although the results may, in part, reflect the corresponding availability of genetic techniques over the given time frame, the variable use of genetic information for listing decisions has the potential to misguide conservation actions. Future management policy would benefit from guidelines for the critical evaluation of genetic information to list or delist organisms under the Endangered Species Act. Resumen:,La información genética se está convirtiendo en un factor influyente para determinar sí una especie, subespecie y segmentos poblacionales distintos califican para ser protegidos por el Acta de Especies en Peligro de E. U. A. Sin embargo, actualmente no hay estándares o lineamientos que definan como deben utilizar información genética las agencias federales que administran el acta. Examiné las decisiones de enlistado basadas en información genética tomadas en un período de 10 años (febrero 1996,febrero 2006). Hubo una amplia variación en los datos genéticos utilizados para informar las decisiones de enlistado en términos de cuáles genomas (mitocondrial vs. nuclear) fueron muestreados y el número de marcadores (o técnicas genéticas) y los loci evaluados. En general, las agencias federales identificaron diferencias genéticas entre unidades taxonómicas putativas o poblaciones dependiendo del tipo y cantidad de datos genéticos. Los estudios que se basaron en marcadores genéticos múltiples tuvieron mayor probabilidad de identificar distinciones, y esos organismos tuvieron mayor probabilidad de recibir protección, que los estudios basados en un solo marcador genético. Aunque los resultados pueden, en parte, reflejar la disponibilidad de técnicas genéticas para decisiones de enlistado en el período analizado, el uso variable de información genética para la toma de decisiones puede desinformar acciones de conservación. Las políticas de manejo futuras se beneficiarían de directrices para la evaluación crítica de información genética para enlistar o quitar de la lista a organismos bajo el Acta de Especies en Peligro. [source] Worster-Drought syndrome: poorly recognized despite severe and persistent difficulties with feeding and speechDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 1 2010MARIA CLARK Aim, Worster-Drought syndrome (WDS), or congenital suprabulbar paresis, is a permanent movement disorder of the bulbar muscles causing persistent difficulties with swallowing, feeding, speech, and saliva control owing to a non-progressive disturbance in early brain development. As such, it falls within the cerebral palsies. The aim of this study was to describe the physical and neuropsychological profiles of children with WDS. Method, Forty-two children with WDS (26 males, 16 females; mean age 7y 10mo, SD 3y 1mo; range 2y 6mo to 16y 5mo) were studied prospectively using a standard protocol. Results, All of the children had severe bulbar dysfunction; 36 out of 42 had feeding difficulties and 23 of 38 had unintelligible speech, which was poorly compensated for by augmentative communication. There were accompanying disturbances in cognition (mean non-verbal IQ 59), behaviour (12/40 attention-deficit,hyperactivity disorder [ADHD]), social communication (8/42 autism), and epilepsy (12/39). The severity of bulbar dysfunction and impact of additional impairments made it difficult to use formal assessments. Interpretation, WDS causes severe and persistent bulbar dysfunction that is often accompanied by additional impairments, as in other cerebral palsies. Speech prognosis is particularly poor. Early diagnosis with appreciation of the underlying neurology would encourage critical evaluation of interventions and long-term planning to improve outcome. [source] IS EDUCATIONAL POLICY MAKING RATIONAL , AND WHAT WOULD THAT MEAN, ANYWAY?EDUCATIONAL THEORY, Issue 5 2009Eric Bredo In Moderating the Debate: Rationality and the Promise of American Education, Michael Feuer raises concerns about the consequences of basing educational policy on the model of rational choice drawn from economics. Policy making would be better and more realistic, he suggests, if it were based on a newer procedural model drawn from cognitive science. In this essay Eric Bredo builds on Feuer's analysis by offering a more systematic critique of the traditional model of rationality that Feuer criticizes, a more critical evaluation of the procedural model that he favors, and a recommendation that the situational model he does not consider may have some benefits over both. This analysis shows that the traditional model presupposes an actor that cannot learn or develop. While the actor in the procedural model can learn, Bredo contends that it cannot develop, that is, it cannot outgrow its initial assumptions and values. Only the situational model allows for learning and development, important in a model to be used in the field of education. Bredo also considers in his analysis the social-relational assumptions built into the traditional, procedural, and situational models and the likely ethical consequences of acting on them. [source] REVIEW: Behavioural assessment of drug reinforcement and addictive features in rodents: an overviewADDICTION BIOLOGY, Issue 1 2006Carles Sanchis-Segura ABSTRACT Some psychoactive drugs are abused because of their ability to act as reinforcers. As a consequence behavioural patterns (such as drug-seeking/drug-taking behaviours) are promoted that ensure further drug consumption. After prolonged drug self-administration, some individuals lose control over their behaviour so that these drug-seeking/taking behaviours become compulsive, pervading almost all life activities and precipitating the loss of social compatibility. Thus, the syndrome of addictive behaviour is qualitatively different from controlled drug consumption. Drug-induced reinforcement can be assessed directly in laboratory animals by either operant or non-operant self-administration methods, by classical conditioning-based paradigms such as conditioned place preference or sign tracking, by facilitation of intracranial electric self-stimulation, or, alternatively by drug-induced memory enhancement. In contrast, addiction cannot be modelled in animals, at least as a whole, within the constraints of the laboratory. However, various procedures have been proposed as possible rodent analogues of addiction's major elements including compulsive drug seeking, relapse, loss of control/impulsivity, and continued drug consumption despite negative consequences. This review provides an extensive overview and a critical evaluation of the methods currently used for studying drug-induced reinforcement as well as specific features of addictive behaviour. In addition, comic strips that illustrate behavioural methods used in the drug abuse field are provided given for free download under http://www.zi-mannheim/psychopharmacology.de [source] The utility of reproductive skew models in the study of male primates, a critical evaluationEVOLUTIONARY ANTHROPOLOGY, Issue 2 2010Markus Port First page of article [source] A critical evaluation of genomic control methods for genetic association studiesGENETIC EPIDEMIOLOGY, Issue 4 2009Tony Dadd Abstract Population stratification is an important potential confounder of genetic case-control association studies. For replication studies, limited availability of samples may lead to imbalanced sampling from heterogeneous populations. Genomic control (GC) can be used to correct ,2 test statistics which are presumed to be inflated by a factor ,; this may be estimated by a summary ,2 value (,median or ,mean) from a set of unlinked markers. Many studies applying GC methods have used fewer than 50 unlinked markers and an important question is whether this can adequately correct for population stratification. We assess the behavior of GC methods in imbalanced case-control studies using simulation. SNPs are sampled from two subpopulations with intra-continental levels of FST (,0.005) and sampling schemata ranging from balanced to completely imbalanced between subpopulations. The sampling properties of ,median and ,mean are explored using 6,1,600 unlinked markers to estimate Type 1 error and power empirically. GC corrections based on the ,2 -distribution (GCmedian or GCmean) can be anti-conservative even when more than 100 single nucleotide polymorphisms (SNPs) are genotyped and realistic levels of population stratification exist. The GCF procedure performs well over a wider range of conditions, only becoming anti-conservative at low levels of , and with fewer than 25 SNPs genotyped. A substantial loss of power can arise when population stratification is present, but this is largely independent of the number of SNPs used. A literature survey shows that most studies applying GC have used GCmedian or GCmean, rather than GCF, which is the most appropriate GC correction method. Genet. Epidemiol. 2009. © 2008 Wiley Liss, Inc. [source] What Is Ecological Validity?INFANCY, Issue 4 2001A Dimensional Analysis Ecological validity has typically been taken to refer to whether or not one can generalize from observed behavior in the laboratory to natural behavior in the world. Although common in current discussions of research, the idea of ecological validity has a long history in psychological thought. A brief historical examination of this idea reveals that concerns with ecological validity are evident in multiple dimensions of experimental work, including the nature of the experimental setting, the stimuli under investigation, and the observer's response employed as the measure. One problem with this multidimensionality, however, is that no explicit criteria have been offered for applying this concept to an evaluation of research. One consequence of this problem is that concerns with ecological validity can be raised in most experimental situations. This article includes a discussion of some demands of ecological validity and the nature of these different dimensions, as well as a critical evaluation of research on the development of mobility with respect to these constraints. [source] Medical management of left-sided ulcerative colitis and ulcerative proctitis: Critical evaluation of therapeutic trialsINFLAMMATORY BOWEL DISEASES, Issue 10 2006Miguel Regueiro MD Abstract Background: The goal of this work was to critically evaluate the published studies on the treatment of ulcerative proctitis (UP) and left-sided ulcerative colitis (L-UC). The results of this review provided the content for the accompanying treatment guidelines, Clinical Guidelines for the Medical Management of Left-sided Ulcerative Colitis and Ulcerative Proctitis: Summary Statement. Methods: All English language articles published between 1995 and September 2005 were identified through a comprehensive literature search using OVID and PubMed. The quality of the data supporting or rejecting the use of specific therapies was categorized by a data quality grading scale. An "A+" grade was assigned to treatment supported by multiple high-quality randomized controlled trials with consistent results, whereas a "D" grade was given to therapy supported only by expert opinion. The therapeutic efficacy of a treatment was defined by its success in treating UP and L-UC compared with placebo. A medication was ranked as "excellent" if it was specifically studied for UP and L-UC and had consistently positive results compared with placebo or another agent. Quality and efficacy scores were agreed on by author consensus. Results: For the acute treatment of UP or L-UC, the rectally administered corticosteroids and mesalazine (5-ASA), either alone or in combination with oral 5-ASAs, are the most effective therapy: evidence quality, A+; efficacy, excellent. Only rectally administered 5-ASA received an A+/excellent rating for maintenance of remission. Infliximab received an A+ grade for induction and maintenance of remission but only a "good" rating because the studies were performed in all UC, not specifically UP or L-UC. Conclusions: This critical evaluation of treatment provides a "report card" on medications available for the management of patients with UP and L-UC. The guidelines should provide a useful reference and supplement for physicians treating UC patients. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||