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Practical Challenges (practical + challenge)
Selected AbstractsDimensions and dynamics of irregular migrationPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2010Khalid Koser Abstract This contribution critically reviews existing data and other recent sources to provide an overview of the dimensions and dynamics of contemporary irregular migration. First it considers the utility and uses of irregular migrant statistics, considering their inherent inaccuracy, their inability to distinguish different types of irregular migrant, the way that data is collected, and the purposes to which it is put. The second section reviews the conceptual and practical challenges associated with counting irregular migrants. Conceptual challenges include: differentiating stocks from flows, addressing the variety of routes into irregularity, distinguishing migrant smuggling from human trafficking, separating asylum from aggregate statistics, and acknowledging that migrants' legal status can change quickly. Practical challenges associated with a series of direct and indirect methods for collecting statistics (including national censuses) are reviewed, and the difficulty for researchers to access official statistics highlighted. The third section presents estimates of the scale and scope of irregular migration, and data from regularisation programmes in various high-income countries. The fourth section reviews explanations for irregular migration, distinguishing macro-level explanations that focus on structural causes from meso-level explanations concerned with the role of policies and intermediaries, and also notes the shortage of micro-level explanations concerned with individual and family decision-making. The final section considers the consequences of irregular migration, with a particular focus on security. The review suggests that while irregular migration can undermine state sovereignty, the implications of irregular migration for the ,human security' of those involved should not be underestimated. The conclusion considers some implications for future research. Copyright © 2009 John Wiley & Sons, Ltd. [source] Top-up Payments for Expensive Cancer Drugs: Rationing, Fairness and the NHSTHE MODERN LAW REVIEW, Issue 3 2010Article first published online: 7 MAY 2010, Emily Jackson This article examines the implications for patient care, and for the future of rationing within the NHS, of the recent decision to permit NHS patients to supplement their care by paying for medicines , mainly expensive new cancer drugs , which are not available within the NHS. The starting point is the recommendations of the Richards' Report and their implementation through new guidance issued by the Department of Health and the National Institute for Health and Clinical Excellence. Practical challenges arise from the insistence upon the ,separate' delivery of self-funded medicines, and more flexible cost-effectiveness thresholds for end of life medicines may have repercussions for other patients. While undoubtedly part of the trend towards explicit rationing, top-up fees might also represent a significant step towards regarding the NHS as a core, basic service. Finally, the issue of top-up fees is located within the broader context of current cancer research priorities and persisting health inequalities. [source] Where is the wisdom?JOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 6 2009A conceptual history of evidence-based medicine Abstract Rationale, Evidence-based medicine (EBM) has been acclaimed as a major advance in medical science, but criticized as a proposed alternative model for the practice and teaching of medicine. Ambiguity regarding the proper role of the contributions of EBM within the fabric of medicine and health care has contributed to this discrepancy. Aims and objectives, We undertook a critical review of the history of the EBM movement, beginning with its origins in the 1970s and continuing through this century. We drew upon the results of an independent project that rationalized the EBM domain from the perspective of educational evaluation and assessment. We considered the content of EBM in relationship to the propositions and promises embodied in advocacy publications. Results, EBM emerged in the context of the explosion of biomedical information in the decade preceding public access to the Internet in the mid-1990s and drew upon the independently derived ,information literacy' formula developed by information scientists during the 1980s. The critically important content and achievements of EBM are fully explained within the confines of the information literacy model. The thesis that EBM offers an alternative paradigm for individualized health care, asserted in the advocacy literature, is not supported by published models of evidence-based clinical practice. Conclusion, A critical historical review of the origins, content and development of the EBM movement proposes that full integration of the fruits of the movement into routine clinical care remains a conceptual and practical challenge. [source] Utilizing Peer Nominations in Middle School: A Longitudinal Comparison Between Complete Classroom-Based and Random List MethodsJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 2 2010Amy Bellmore Although peer nominations provide invaluable data on social status and reputations of classmates, the large size and organizational structure of secondary schools pose a practical challenge to utilizing nomination methods. Particularly problematic is determining the appropriate reference group when students are no longer in self-contained classrooms. In the current study, we compared a random list method as an alternative to complete classroom-based or grade list peer nominations. In a 3-year longitudinal study of 2,307 middle school students, the temporal stability and construct validity of the method were assessed regarding peer acceptance, rejection, coolness, aggression, and victimization. The findings suggested that the random list procedure provides a feasible method to study large peer groups in secondary school settings. [source] Mycoviruses of filamentous fungi and their relevance to plant pathologyMOLECULAR PLANT PATHOLOGY, Issue 1 2009MICHAEL N. PEARSON SUMMARY Mycoviruses (fungal viruses) are reviewed with emphasis on plant pathogenic fungi. Based on the presence of virus-like particles and unencapsidated dsRNAs, mycoviruses are common in all major fungal groups. Over 80 mycovirus species have been officially recognized from ten virus families, but a paucity of nucleic acid sequence data makes assignment of many reported mycoviruses difficult. Although most of the particle types recognized to date are isometric, a variety of morphologies have been found and, additionally, many apparently unencapsidated dsRNAs have been reported. Until recently, most characterized mycoviruses have dsRNA genomes, but ssRNA mycoviruses now constitute about one-third of the total. Two hypotheses for the origin of mycoviruses of plant pathogens are discussed: the first that they are of unknown but ancient origin and have coevolved along with their hosts, the second that they have relatively recently moved from a fungal plant host into the fungus. Although mycoviruses are typically readily transmitted through asexual spores, transmission through sexual spores varies with the host fungus. Evidence for natural horizontal transmission has been found. Typically, mycoviruses are apparently symptomless (cryptic) but beneficial effects on the host fungus have been reported. Of more practical interest to plant pathologists are those viruses that confer a hypovirulent phenotype, and the scope for using such viruses as biocontrol agents is reviewed. New tools are being developed based on host genome studies that will help to address the intellectual challenge of understanding the fungal,virus interactions and the practical challenge of manipulating this relationship to develop novel biocontrol agents for important plant pathogens. [source] Prospecting for (Campaign) GoldAMERICAN JOURNAL OF POLITICAL SCIENCE, Issue 2 2007Wendy K. Tam Cho Campaigns and political parties are faced with the immensely important practical challenge of financing their efforts. Raising money is instrumental to all other aims. In recent years, this task has been complicated by the need to enlist ever greater numbers of contributors to raise ever larger sums of money. At the same time, fundraising burdens are eased a bit because contributors flock together. That is, campaign contributing is a spatially dependent phenomenon, associated with affluence and the presence of networks. Accordingly, geospatial tools provide a helpful method for understanding and predicting where contributions can be most successfully mined. [source] On the Generation of Catalytic Antibodies by Transition State AnaloguesCHEMBIOCHEM, Issue 4 2003Montserrat Barbany Abstract The effective design of catalytic antibodies represents a major conceptual and practical challenge. It is implicitly assumed that a proper transition state analogue (TSA) can elicit a catalytic antibody (CA) that will catalyze the given reaction in a similar way to an enzyme that would evolve (or was evolved) to catalyze this reaction. However, in most cases it was found that the TSA used produced CAs with relatively low rate enhancement as compared to the corresponding enzymes, when these exist. The present work explores the origin of this problem, by developing two approaches that examine the similarity of the TSA and the corresponding transition state (TS). These analyses are used to assess the proficiency of the CA generated by the given TSA. Both approaches focus on electrostatic effects that have been found to play a major role in enzymatic reactions. The first method uses molecular interaction potentials to look for the similarity between the TSA and the TS and, in principle, to help in designing new haptens by using 3D quantitative struture,activity relationships. The second and more quantitative approach generates a grid of Langevin dipoles, which are polarized by the TSA, and then uses the grid to bind the TS. Comparison of the resulting binding energy with the binding energy of the TS to the grid that was polarized by the TS provides an estimate of the proficiency of the given CA. Our methods are used in examining the origin of the difference between the catalytic power of the 1F7 CA and chorismate mutase. It is demonstrated that the relatively small changes in charge and structure between the TS and TSA are sufficient to account for the difference in proficiency between the CA and the enzyme. Apparently the environment that was preorganized to stabilize the TSA charge distribution does not provide a sufficient stabilization to the TS. The general implications of our findings and the difficulties in designing a perfect TSA are discussed. Finally, the possible use of our approach in screening for an optimal TSA is pointed out. [source] Postexposure feeding depression: A new toxicity endpoint for use in laboratory studies with Daphnia magnaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2002Ruth A. McWilliam Abstract In situ bioassays with daphnids currently employ lethality as an endpoint, and although sublethal responses (reproduction and feeding rate) can be measured in the field, such endpoints pose major practical challenges. Previous studies have indicated that Daphnia magna exposed to toxic substances can exhibit delayed recovery in feeding behavior (postexposure feeding depression). This simple, robust response has the potential to be an ecologically relevant and potentially diagnostic endpoint. This study developed and tested the use of postexposure feeding depression as a toxicity endpoint in the laboratory environment. First, replicate numbers were manipulated to produce statistically reliable results. Second, postexposure feeding depression in D. magna was studied under laboratory conditions, by employing toxic substances with differing modes of action. Although most substances caused feeding inhibition during direct exposure, not all substances produced postexposure feeding depression. However, the use of lethality as a supplementary endpoint provided an alternative measure when no feeding depression was apparent after exposure. In combination, these endpoints offer a potentially more sensitive, ecologically relevant alternative to the use of lethality alone for in situ bioassay studies. [source] Drug,polymer solubility and miscibility: Stability consideration and practical challenges in amorphous solid dispersion developmentJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2010Feng Qian Abstract Drug,polymer solid dispersion has been demonstrated as a feasible approach to formulate poorly water-soluble drugs in the amorphous form, for the enhancement of dissolution rate and bioperformance. The solubility (for crystalline drug) and miscibility (for amorphous drug) in the polymer are directly related to the stabilization of amorphous drug against crystallization. Therefore, it is important for pharmaceutical scientists to rationally assess solubility and miscibility in order to select the optimal formulation (e.g., polymer type, drug loading, etc.) and recommend storage conditions, with respect to maximizing the physical stability. This commentary attempts to discuss the concepts and implications of the drug,polymer solubility and miscibility on the stabilization of solid dispersions, review recent literatures, and propose some practical strategies for the evaluation and development of such systems utilizing a working diagram. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:2941,2947, 2010 [source] Modelling price paths in on-line auctions: smoothing sparse and unevenly sampled curves by using semiparametric mixed modelsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 2 2008Florian Reithinger Summary., On-line auctions pose many challenges for the empirical researcher, one of which is the effective and reliable modelling of price paths. We propose a novel way of modelling price paths in eBay's on-line auctions by using functional data analysis. One of the practical challenges is that the functional objects are sampled only very sparsely and unevenly. Most approaches rely on smoothing to recover the underlying functional object from the data, which can be difficult if the data are irregularly distributed. We present a new approach that can overcome this challenge. The approach is based on the ideas of mixed models. Specifically, we propose a semiparametric mixed model with boosting to recover the functional object. As well as being able to handle sparse and unevenly distributed data, the model also results in conceptually more meaningful functional objects. In particular, we motivate our method within the framework of eBay's on-line auctions. On-line auctions produce monotonic increasing price curves that are often correlated across auctions. The semiparametric mixed model accounts for this correlation in a parsimonious way. It also manages to capture the underlying monotonic trend in the data without imposing model constraints. Our application shows that the resulting functional objects are conceptually more appealing. Moreover, when used to forecast the outcome of an on-line auction, our approach also results in more accurate price predictions compared with standard approaches. We illustrate our model on a set of 183 closed auctions for Palm M515 personal digital assistants. [source] Dimensions and dynamics of irregular migrationPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2010Khalid Koser Abstract This contribution critically reviews existing data and other recent sources to provide an overview of the dimensions and dynamics of contemporary irregular migration. First it considers the utility and uses of irregular migrant statistics, considering their inherent inaccuracy, their inability to distinguish different types of irregular migrant, the way that data is collected, and the purposes to which it is put. The second section reviews the conceptual and practical challenges associated with counting irregular migrants. Conceptual challenges include: differentiating stocks from flows, addressing the variety of routes into irregularity, distinguishing migrant smuggling from human trafficking, separating asylum from aggregate statistics, and acknowledging that migrants' legal status can change quickly. Practical challenges associated with a series of direct and indirect methods for collecting statistics (including national censuses) are reviewed, and the difficulty for researchers to access official statistics highlighted. The third section presents estimates of the scale and scope of irregular migration, and data from regularisation programmes in various high-income countries. The fourth section reviews explanations for irregular migration, distinguishing macro-level explanations that focus on structural causes from meso-level explanations concerned with the role of policies and intermediaries, and also notes the shortage of micro-level explanations concerned with individual and family decision-making. The final section considers the consequences of irregular migration, with a particular focus on security. The review suggests that while irregular migration can undermine state sovereignty, the implications of irregular migration for the ,human security' of those involved should not be underestimated. The conclusion considers some implications for future research. Copyright © 2009 John Wiley & Sons, Ltd. [source] The Theory and Practice of Group Representation: Reflections on the Governance of Race Equality in BirminghamPUBLIC ADMINISTRATION, Issue 2 2005Graham Smith A number of political theorists have recently argued that group representation is essential to the achievement of social justice. However relatively little work exists on the institutional implications of such arguments beyond the analysis of electoral mechanisms to achieve greater representation within legislatures. This leaves unanswered one of the most difficult questions facing policy-makers , how to effectively engage the range of Black and minority ethnic (BME) communities in decision-making processes. Through a detailed analysis of the changing nature of the arrangements in place in Birmingham (UK) to engage BME communities, this paper is able to reflect on the theoretical and practical challenges of group representation in contemporary polities. [source] Practitioner Review: Bridging the gap between research and clinical practice in pediatric obesityTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 2 2007Elissa Jelalian Background:, Pediatric obesity is a significant public health concern, with rising prevalence rates in both developed and developing countries. This is of particular significance given that overweight children and adolescents are at increased risk for multiple medical comorbidities, as well as psychosocial and behavioral difficulties. The current review highlights findings from the empirical pediatric obesity treatment literature, with particular attention to diet, physical activity, and behavior interventions. Evaluation and treatment considerations relevant to working with overweight children and adolescents with psychiatric comorbidities are reviewed. Methods:, Review of the relevant treatment literature, with a focus on randomized clinical trials, was conducted. Recommendations regarding treatment of children and adolescents with psychiatric comorbidities are based on relevant prospective studies of the relationship between weight status and psychological variables and studies with adult populations. Results:, Well-established pediatric weight control interventions have been conducted in research settings. These studies provide a starting point, but are limited by homogeneous samples that may exclude participants with psychiatric comorbidities. Practitioners treating obese children and adolescents with psychiatric disorders are encouraged to assess individual, familial, and contextual variables specific to weight (e.g., motivation and existing support to change current eating and physical activity patterns, extent of weight-related conflict within family, impact of weight on current functioning) in order to prioritize treatment objectives. Conclusions:, The review concludes with a discussion of current empirical and practical challenges, including explicitly targeting obese children and adolescents with psychiatric concerns and determining appropriateness of pursuing weight control interventions in this population. [source] DOCUMENTING LOCAL CULTURE: AN INTRODUCTORY FIELD SCHOOLANNALS OF ANTHROPOLOGICAL PRACTICE, Issue 1 2004Philip B. Stafford This chapter provides a detailed description of a three-week summer residential field school conducted in Bloomington, Indiana, in 2000 and 2001. Following a model developed by David A. Taylor of the American Folklife Center, the school provided instruction and hands-on experience to students interested in learning methods of cultural fieldwork including interviewing, photography and participant-observation. Additionally, students learned methods of documentation including archiving and exhibition through radio, video, and other public displays. Each field school was organized around a salient local theme: the public square, in year 1 and community and disability, in year 2. This chapter summarizes the multiple practical challenges that students and instructors face in conducting a successful fieldwork school, with reference to transportation, supervision, field ethics, meals, residential accommodations, equipment, teamwork, and exiting the field. [source] Felt tip pens and school councils: children's participation rights in four English schoolsCHILDREN & SOCIETY, Issue 4 2001Dominic Wyse The United Nation Convention on the Rights of the Child has created practical challenges for nation states and institutions particularly in relation to children's rights to participation. The limited research that is available has tended to use survey methodology; qualitative accounts of children's daily lives are rare. The present study investigated the nature of children's participation in their education in two primary and two secondary schools; in particular the right to express views freely in all matters affecting the child. The study found that children's opportunities to express their views were extremely limited even when school councils were in place. It is concluded that the goal of active citizenship espoused by recent national curriculum developments will remain illusive unless educational practice changes to a focus on school processes rather than products. Copyright © 2001 John Wiley & Sons, Ltd. [source] How do teenagers manage their food allergies?CLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2010H. Monks Summary Background The peak incidence of deaths from anaphylaxis associated with nut allergy occurs in teenagers and young adults. During adolescence, the management of food allergy shifts from being the responsibility of parents to that of the young person. This is a group who therefore need special attention in the clinic. Objective This study aimed to understand the practical challenges that teenagers with food allergy experience using a qualitative approach and generate potential interventions for tackling these. Methods Teenagers aged 1118 years with food allergy completed a questionnaire about their food allergy and underwent a focused, semi-structured interview with open questions guided by a priori topic areas. Interviews were recorded, transcribed and analysed using a thematic approach. Results The study enrolled 18 teenagers with a median age of 15 years (10 females); the most common food allergens were peanuts and tree nuts. Three key themes emerged: avoidance of allergens, preparation for reactions and the treatment of reactions. The majority of teenagers reported eating foods labelled as ,may contain' an allergen as they perceive that they are actually very unlikely to contain an allergen. Many of the teenagers only carried their self-injectable adrenaline when they thought they are particularly at risk of a reaction. Some do not know how to appropriately treat an allergic reaction. More than half believed that educating other students at school about the seriousness of food allergies would make it easier to live with their food allergy. Conclusions A significant number of teenagers demonstrate risk-taking behaviour in the management of their food allergies. Teenagers also felt it would be helpful for their peers to be educated about food allergy. This novel strategy might help them to avoid trigger foods and enable teenagers to access help more readily if they suffer a reaction. Cite this as: H. Monks, M. H. Gowland, H. MacKenzie, M. Erlewyn-Lajeunesse, R. King, J. S. Lucas and G. Roberts, Clinical & Experimental Allergy, 2010 (40) 1533,1540. [source] | ||||||||||||||||||||||