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Selected AbstractsHow to read and understand and use systematic reviews and meta-analysesACTA PSYCHIATRICA SCANDINAVICA, Issue 6 2009S. Leucht Objective,: Systematic reviews and meta-analyses are increasingly frequently used in the evaluation of medical treatments. This review explains the principles of the methodology, significance and limitations of systematic reviews. Method:, Short review article. Results:, In contrast to conventional reviews, systematic reviews use a structured approach in retrieving, analyzing and interpreting the evidence. A comprehensive search strategy is applied to identify all relevant trials. Study selection and data extraction is performed independently by at least two reviewers. The data are usually synthesized in a meta-analysis applying statistical methods to examine homogeneity. Funnel plots and other statistical methods are applied to detect publication bias. Conclusion:, Due to the enormous amount of scientific information published every year, systematic reviews and meta-analyses have become indispensable methods for the evaluation of medical treatments. [source] Novel microwave,freeze drying of onion slicesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 5 2009Soleiman Abbasi Summary The present study aimed to introduce the capability of a novel dehydration technique. To do so, slices with various thicknesses (3.5 and 7 mm) of white onions were dried using commercial freeze drier (abs. pressure 0.005 mbar, temp. 45 °C), our own designed microwave-vacuum drier (abs. pressure down to 300 mbar) under various microwave powers (120,1200 W) and microwave-vacuum,freeze drier (onion slices kept at ,20 °C for 2 h). Then, their dehydration rates and some quality parameters, such as rehydration ratio, colour (L*, a* and b*) and micro-structure were investigated. Our findings showed that microwave-vacuum,freeze drier is practically a rapid, simple, efficient, economic and novel dehydration technique which can be used for dehydration of mainly foodstuffs. The quality properties of slices produced by this novel method were also completely comparable and competitive with commercial freeze drier with over 96% saving on processing time and enormous amount on energy and capital investments. [source] Will agri-environment schemes deliver substantial biodiversity gain, and if not why not?JOURNAL OF APPLIED ECOLOGY, Issue 1 2007MARK J. WHITTINGHAM Summary 1One of the main aims of agri-environment schemes (AES) is to increase biodiversity on farmland. Common conservation practice is to identify areas containing valuable resources (e.g. habitats, ecosystems and species) and then to protect them: ,protected area' schemes. AES differ from typical protected area schemes because they are often applied to small patches of land, such as field boundaries, and are sometimes located in areas where the target species does not occur. 2AES require an enormous amount of funding and they have been applied across a large geographical area, i.e. the European Union. However, recent evidence suggests mixed results regarding the effects of AES on biodiversity. 3It is hard to predict the consequences of AES on biodiversity because a number of factors are seldom accounted for explicitly. For example: (i) the occurrence of target species will vary between patches; (ii) there will be variation in habitat preference by species in different geographical areas; (iii) both optimal foraging theory and metapopulation theory predict that the distance from breeding individuals is likely to determine patch use; (iv) if resources are widely spread then the home ranges of some species may need to increase to encompass the multiple resources needed for breeding. The potential for these factors to affect the outcome of AES on biodiversity is discussed. 4Synthesis and applications. AES are likely to increase biodiversity if a lower number of larger resource patches are provided, in contrast to current practice that promotes many small fragmented areas of environmental resource. One way of achieving this may be to run these schemes more like traditional protected area schemes, with farms or groups of farms managed using extensive farming methods. Such an approach negates some of the problems of current AES and may help to address a wider range of concerns held by different countryside stakeholders. [source] Treatment of basal cell carcinomas in patients with nevoid basal cell carcinoma syndromeJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2009S Van Der Geer Abstract Background, Nevoid basal cell carcinoma syndrome (NBCCS) is characterized by the development of multiple basal cell carcinomas (BCCs). A major problem for these patients is the enormous amount of BCCs which can invade in the deep underlying structures, especially in the face. Different treatment modalities are used in these patients; surgical excision, Mohs micrographic surgery, cryotherapy, photodynamic therapy, ablative laser therapy and topical 5% imiquimod. There is no evidence based advice how to treat a NBCCS patient. Objective, To give a review of the literature about the possible treatment modalities for the multiple BCCs in NBCCS patients. Results, Literature consists mainly of case reports; no evidence based advice how to treat a NBCCS patient exists. Multiple treatments are available (surgical and non-surgical), and a lot of them can be combined. Treatment in a megasession is an option to diminish the medical and social inconvenience for the patient. Conflicts of interest None declared [source] Toxicology and health risks of hydroquinone in skin lightening formulationsJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 7 2006TJ Kooyers ABSTRACT Background, Hydroquinone has been used for decades as a skin lightening agent. As a result of concerns about mid-term effects like leukomelanoderma en confetti and exogenous ochronosis, its use in cosmetics has been banned since January 2001. Objective, Until recently no attention was paid to potential long-term side-effects, despite the fact that there are indications that these may exist. It was decided that a clearer picture of these potential long term effects was needed. Methods, A literature search was conducted with an emphasis on the biochemistry and toxicology of hydroquinone, benzene and related molecules. Results, It appeared that since 1996 an enormous amount of articles have been published on the carcinogenicity of hydroquinone, benzene and related molecules. The literature search on hydroquinone as a skin lightening agent suggests that possible long-term effects like carcinogenesis may be expected. Conclusion, The risks of long-term effects (cancer) of topically applied hydroquinone may no longer be ignored. Based on recent evidence of the potential risks, which are higher than has been assumed up until now, we plead that the use of hydroquinone as a skin lightening agent will be stopped completely. [source] Combined Use of PCA and QSAR/QSPR to Predict the Drugs Mechanism of Action.MOLECULAR INFORMATICS, Issue 4 2009An Application to the NCI ACAM Database Abstract During the years the National Cancer Institute (NCI) accumulated an enormous amount of information through the application of a complex protocol of drugs screening involving several tumor cell lines, grouped into panels according to the disease class. The Anti-cancer Agent Mechanism (ACAM) database is a set of 122 compounds with anti-cancer activity and a reasonably well known mechanism of action, for which are available drug screening data that measure their ability to inhibit growth of a panel of 60 human tumor lines, explicitly designed as a training set for neural network and multivariate analysis. The aim of this work is to adapt a methodology (previously developed for the analysis of DNA minor groove binders) for the analysis of NCI ACAM database, using Principal Component Analysis (PCA) and QSAR/QSPR for the prediction of the mechanism of action of anti-cancer drugs. The entire database was splitted in a training set of 60 structures and a test set of 48 ones, and each set was expressed in form of a matrix on which further procedures were performed. Three statistical parameters were calculated: First Attempt of Prediction (FAP) expresses the percentage of correct predictions at first attempt, Total Attempt of Prediction (TAP) expresses the total percentage of correct predictions across all the three attempts, Non-Classified (NC) expresses the percentage of compounds whose mechanism of action has failed to be predicted. The predictive ability of this approach is variable, but the results obtained are generally good; using 50% Growth Inhibiting concentration (GI50) values as training data, we were able to assign a correct mechanism of action with a good degree of reliability (more than 79%). [source] Sodium, blood pressure, and ethnicity: What have we learned?,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2009Lillian Gleiberman An enormous amount of research has yielded significant knowledge about ethnic differences in sodium homeostasis and blood pressure regulation. Consistent findings such as greater sodium-sensitivity, lower potassium excretion and high higher serum sodium levels in African Americans need further exploration to define more precise physiological mechanisms. The genetic alleles associated with sodium homeostasis in relation to blood pressure have accounted for only a small proportion of the variance in blood pressure. Several allelic variants differ in frequency among ethnic groups and heat-adapted genetic variants have a high prevalence in low latitudes and hot, wet climates which lends support to the "sodium retention" hypothesis. The blood pressure disparities between African Americans and whites may, in part, be due to different allelic frequencies of genes associated with sodium homeostasis. However, with advances in genomics, environmental factors tend to be neglected in research. Better measures of environmental stress have recently been developed by anthropologists and should be included in research designs by investigators in other disciplines. Public health efforts should encourage food producers to reduce sodium content of its products, and physicians should encourage patients to reduce consumption of high sodium packaged and fast foods. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Biomedical applications of capillary electrophoresis with laser-induced fluorescence detectionBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 7-8 2001Ximena Páez Abstract Capillary electrophoresis (CE) is a high-efficiency analytical technique that has had a great impact as a tool in biomedical research, clinical and forensic practice in the last ten years. Only in one of the applications, the DNA analysis, it has had an explosive exponential growth in the last few years. This impact is expressed in an enormous amount of CE articles and many reviews. The CE advantages with respect to other analytical techniques: the required very small sample volume, rapid analysis, great resolution power and low costs, have made this technique ideal for the analysis of a numerous endogenous and exogenous substances present in biological fluids. The different modes of CE have been coupled to different detection techniques such as UV-absorbance, electrochemical, mass spectrometry and laser-induced fluorescence detection (LIFD) to detect different nature and molecular size separated analytes. This review focuses mostly on the applications of CE,LIFD, to measure drugs and endogenous neuroactive substances such as amino acids and monoamines, especially in microdialysis samples from experimental animals and humans. CE,LIFD trends are discussed: automated faster analysis with capillary array systems, resolution power improvement, higher detection sensitivity, and CE systems miniaturization for extremely small sample volume, in order to make CE easier and affordable to the lab bench or the clinical bed. Copyright © 2001 John Wiley & Sons, Ltd. [source] What neurobiology cannot tell us about addictionADDICTION, Issue 5 2010Harold Kalant ABSTRACT Molecular neurobiological studies have yielded enormous amounts of valuable information about neuronal response mechanisms and their adaptive changes. However, in relation to addiction this information is of limited value because almost every cell function appears to be involved. Thus it tells us only that neurons adapt to ,addictive drugs' as they do to all sorts of other functional disturbances. This information may be of limited help in the development of potential auxiliary agents for treatment of addiction. However, a reductionist approach which attempts to analyse addiction at ever finer levels of structure and function, is inherently incapable of explaining what causes these mechanisms to be brought into play in some cases and not in others, or by self-administration of a drug but not by passive exposure. There is abundant evidence that psychological, social, economic and specific situational factors play important roles in initiating addiction, in addition to genetic and other biological factors. Therefore, if we hope to be able to make predictions at any but a statistical level, or to develop effective means of prevention, it is necessary to devise appropriate integrative approaches to the study of addiction, rather than pursue an ever-finer reductive approach which leads steadily farther away from the complex interaction of drug, user, environment and specific situations that characterizes the problem in humans. [source] New directions and interactions in metagenomics researchFEMS MICROBIOLOGY ECOLOGY, Issue 3 2006Naomi Ward Abstract Metagenomics, which aims to access the genomic potential of an environmental sample directly, is a burgeoning area that is generating enormous amounts of biological information. An examination of recent metagenomics literature reveals the discipline to be heading in new and interesting directions, including the investigation of the normal flora of mammals, analysis of ancient genomes, and exploration of the distribution of novel pathways. In addition, the development of new bioinformatics approaches and tools is allowing innovative mining of both existing and new data. Finally, there are indications that the integration of metagenomics with complementary approaches in microbial ecology is beginning. [source] Fabrication of Precise Fluidic Structures in LTCCINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 1 2009Fred Barlow A number of emerging applications of low-temperature co-fired ceramic (LTCC) require embedded fluidic structure within the co-fired ceramic and or precise external dimensional tolerances. These structures enable the control of fluids for cooling, sensing, and biomedical applications, and variations in their geometry from the design can have a significant impact on the overall performance of the devices. One example of this type of application is a multilayer cooler developed recently by the authors for cooling laser diode bars. In many laser systems, laser diodes are the primary emitters, or assemblies of these diode bars are used to pump traditional laser crystals such as Nd:YLF. Assemblies of these diodes require large amounts of electrical current for proper operation, and the device operating temperature must be carefully controlled in order to avoid a shift in the output wavelength. These diodes are packaged into water-cooled assemblies and by their nature dissipate enormous amounts of heat, with waste heat fluxes on the order of 2000 W/cm2. The traditional solution to this problem has been the development of copper multilayer coolers. Assemblies of laser diodes are then formed by stacking these diode bars and coolers. Several problems exist with this approach including the erosion of the copper coolers by the coolant, a requirement for the use of deionized water within the system, and a significant CTE mismatch between the diode bar and the metal cooler. Diodes are bonded to these metal structures and liquid coolant is circulated through the metal layers in order to cool the diode bar. In contrast, the coolers developed by the authors utilize fluid channels and jets formed within LTCC as well as embedded cavity structures to control the flow of a high-velocity liquid and actively cool the laser diode bars mounted on the surface of the LTCC., The dimensional tolerances of these cooler assemblies and complex shapes that are used to control the fluid can have a significant impact on the overall performance of the laser system. This paper describes the fabrication process used to create the precise channel and jet structures used in these LTCC-based coolers, as well as some of the challenges associated with these processes. [source] A Multi-Theoretical Model of Knowledge Transfer in Organizations: Determinants of Knowledge Contribution and Knowledge Reuse*JOURNAL OF MANAGEMENT STUDIES, Issue 2 2006Sharon Watson abstract Knowledge has become one of the most important sources of competitive advantage for firms in many industries, particularly those in which firms provide knowledge services to their clients. Many knowledge intensive firms have spent enormous amounts of time and money trying to find ways to better manage their knowledge resources. Effective leveraging of knowledge resources through the transfer and reuse of existing knowledge is an important aspect of most knowledge management systems. In this study we argue that the effectiveness of intrafirm knowledge transfer based on the reuse of existing knowledge depends on two key factors: (1) the willingness of individuals to contribute their knowledge to the system; and (2) the rate at which individuals access and reuse knowledge within the system. Here we use social exchange theory to develop a model of the factors that will impact the frequency with which individuals contribute their knowledge to the system. Additionally, we use expectancy theory to develop a model of the factors that lead to knowledge reuse. Results of hypothesis tests using data collected from a multinational services firm support our multi-theoretical model, and suggest ways in which the model might be refined. We discuss the implications of these findings for further theory building and for managers engaged in the development and improvement of knowledge management systems. [source] Dynamic Display, Propaganda, and the Reinforcement of Provincial Power in the Inca EmpireARCHEOLOGICAL PAPERS OF THE AMERICAN ANTHROPOLOGICAL ASSOCIATION, Issue 1 2004Dennis Ogburn A primary objective of the Inca state and other early empires was to maintain control over the inhabitants of conquered territories. In addition to overt tactics such as military force, resettlement, alliance formation, and cultural and economic integration, I suggest that many other activities of the Inca state also served to reinforce state power in the provinces. This was achieved by establishing and maintaining a "psychology of submission" in subject peoples through frequent reminders of imperial power, that is, advertising state control over labor. Display in this form was a major implicit element in various activities of the empire, such as the movement of armies, the transport of building stones from Cuzco to Ecuador, and the construction of imperial temples and palaces. These activities served as potent public demonstrations of the state's ability to mobilize large armies and control enormous amounts of labor. Propaganda also played a major role in maintaining the psychology of submission by disseminating information about those activities having an element of display and about other accomplishments of the state to people who did not witness them firsthand. Considered in light of these mechanisms of display and propaganda, many of the apparently wasteful activities of the Inca state can be understood as deliberate and integral to overall imperial strategies for maintaining control in the provinces. [source] | ||||||||||||||||