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Selected AbstractsMesothelin, a possible target for immunotherapy, is expressed in primary AML cellsEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2007Daniel Steinbach Abstract Background:, Mesothelin is a promising candidate for tumor-specific therapy because of its limited expression in normal tissues and high expression in several cancers. The expression of the protein mesothelin in hematological malignancies has not yet been analyzed. SS1(dsFv)PE38 is a recombinant anti-mesothelin immunotoxin which is undergoing clinical evaluation in patients with mesothelin-expressing tumors. Methods and Results:, In this study we show that the mesothelin protein is expressed in leukemic cells from children with acute myeloid leukemia (AML). This finding was confirmed by western blot, immunocytochemistry and real time polymerase chain reaction (PCR). Despite the expression of mesothelin, the patient samples were not sensitive to immunotoxin SS1(dsFv)PE38 in MTT assays. Conclusions:, Primary AML cells express mesothelin but SS1(dsFv)PE38 is not active in killing these cells. Other approaches that utilize mesothelin as a target might be more effective and should be tested against AML cells. [source] Digital imaging in transmission electron microscopyJOURNAL OF MICROSCOPY, Issue 1 2000G. Y. Fan The digital revolution currently under way, as evidenced by the rapid development of the Internet and the world-wide-web technologies, is undoubtedly impacting the field of transmission electron microscopy (TEM). Digital imaging systems based on charge-coupled device (CCD) technologies, with pixel array size up to 2 k × 2 k at the present and increasing, are available for TEM applications and offer many attractions. Is it time to phase out film cameras on TEMs and close the darkrooms for good? This paper reviews digital imaging technologies for TEM at different voltages, and contrasts the performance of digital imaging systems with that of TEM film. The performance characteristics of CCD-based digital imaging systems, as well as methods for assessing them, are discussed. Other approaches to digital imaging are also briefly reviewed. [source] Subjects: Grammatical Relations, Grammatical Functions and Functional CategoriesLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 9 2010Ileana Paul This paper presents an overview of how the notion of ,subject' has been defined in linguistic theory. Although the term developed out of Artistotelian logic, its use has been narrowed to refer to the grammatical relation (or function). Over the past 50 years, the definition of subject and its universality have been the source of much debate. Broadly Chomskian approaches claim that grammatical relations such as subject are not primitives of the grammar and can be derived from phrase structure. As such, testing for the subject involves constituency tests (more recent versions of Chomskian syntax, however, abstract away from constituency). Other approaches (Relational Grammar, Lexical-Function Grammar) posit grammatical relations as primitives of the grammar that are not necessarily related to constituency. And at the other extreme, certain linguists argue that subjects are not found in all languages and therefore the notion is not one of interest (e.g. Role and Reference Grammar). This paper reviews the various analyses of subjects and considers in some detail how the notion of subject has evolved within the Chomskian framework. [source] Short- and long-term consequences of early parental loss in the historical population of the Krummhörn (18th and 19th century)AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2009Kai P. Willführ The impact of the early loss of one's father or one's mother on the survival and age at death of children was investigated on the basis of a historical reconstitution of families from the Krummhörn (East Frisia/Ostfriesland; Germany) with the aid of Kaplan-Meier plots and the Cox regression. In our analyses, we took into account the changed situation of the family after the death of a parent by incorporating the surviving spouse's remarriage or relationships with stepparents. We find that the impact on survival of the children was sex-specific and also depended on whether and at what point in time during childhood their father or mother had died. As expected, children's immediate survival was strongly affected by maternal loss. A few results can be construed as survival diminishing long-term consequences of the early loss of a parent. Daughters who lost their fathers before their first birthday proved to have increased mortality over a longer period of their youth. The age at death of daughters was also lowered if they had to live with a step-mother during early childhood. To interpret these results, three hypotheses, including an (intrinsic) trade-off, compensation and a selection scenario, were tested. Other approaches, which are based, for example, on the extrinsic trade-off between mating effort and parental investment of the surviving parent, also appear to be suitable as an explanation for the long-term consequences, which eventually draws the conclusion that the compensation scenario is the most likely explanation for the consequences of early parental loss. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Progress technology in microencapsulation methods for cell therapyBIOTECHNOLOGY PROGRESS, Issue 4 2009Jean-Michel Rabanel Abstract Cell encapsulation in microcapsules allows the in situ delivery of secreted proteins to treat different pathological conditions. Spherical microcapsules offer optimal surface-to-volume ratio for protein and nutrient diffusion, and thus, cell viability. This technology permits cell survival along with protein secretion activity upon appropriate host stimuli without the deleterious effects of immunosuppressant drugs. Microcapsules can be classified in 3 categories: matrix-core/shell microcapsules, liquid-core/shell microcapsules, and cells-core/shell microcapsules (or conformal coating). Many preparation techniques using natural or synthetic polymers as well as inorganic compounds have been reported. Matrix-core/shell microcapsules in which cells are hydrogel-embedded, exemplified by alginates capsule, is by far the most studied method. Numerous refinement of the technique have been proposed over the years such as better material characterization and purification, improvements in microbead generation methods, and new microbeads coating techniques. Other approaches, based on liquid-core capsules showed improved protein production and increased cell survival. But aside those more traditional techniques, new techniques are emerging in response to shortcomings of existing methods. More recently, direct cell aggregate coating have been proposed to minimize membrane thickness and implants size. Microcapsule performances are largely dictated by the physicochemical properties of the materials and the preparation techniques employed. Despite numerous promising pre-clinical results, at the present time each methods proposed need further improvements before reaching the clinical phase. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Design of Protein,Protein Interaction Inhibitors Based on Protein Epitope MimeticsCHEMBIOCHEM, Issue 6 2009John A. Robinson Prof. Abstract On the scaffold: Grafting protein epitopes onto conformationally designed scaffolds represents a very promising approach to protein ligand design, with potential applications in many areas of chemical biology and molecular medicine. The highlighted article describes the design and anticancer activity of novel p53/MDM2 inhibitors built upon a scorpion toxin scaffold. Other approaches to protein epitope mimetics are also briefly discussed. [source] 3,5-Bis(trifluoromethyl)phenyl Sulfones in the Julia,Kocienski Olefination , Application to the Synthesis of Tri- and Tetrasubstituted OlefinsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 20 2006Diego A. Alonso Abstract 3,5-Bis(trifluoromethyl)phenyl (BTFP) sulfones 8a,d are successfully employed in the modified Julia olefination reaction with carbonyl compounds employing phosphazene base P4- tBu at room temp. in THF, affording tri- and tetrasubstituted olefins in good yields. The Julia,Kocienski olefination between primary alkyl BTFP sulfones 8a,b and aromatic and aliphatic ketones affords the corresponding trisubstituted alkenes in good yields and low stereoselectivities. On the other hand, higher yields and stereoselectivities are obtained in the synthesis of trisubstituted olefins through the other approach, the coupling of secondary alkyl BTFP sulfones 8c,d with aliphatic, aromatic and ,,,-unsaturated aldehydes. For the first time, tetrasubstituted olefins are synthesized by means of the Julia,Kocienski protocol when the isopropyl BTFP sulfone 8c reacts with aliphatic and aromatic ketones, employing P4- tBu as base at THF reflux. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Europe at the MillenniumPOLITICS, Issue 2 2000Mary Kaldor This article argues that the future of the European project depends on the capacity to maintain security. It traces the link between security and political institutions in the case of nation states and, subsequently, blocs. The security of nation states and blocs was defined in terms of the defence of borders against an external enemy and the preservation of law and order within borders. Today, the distinction between internal and external has broken down; ,new wars' are a mixture of war, organised crime and violations of human rights. Security can only be maintained through the extension of law and order beyond borders , through enlargement, migration and citizenship policies, and effective humanitarian intervention. Any other approach could lead to a reversal of the process of integration. This type of security policy is likely to be associated with a very different type of polity. [source] Current Approaches to Venous Ulcers and CompressionDERMATOLOGIC SURGERY, Issue 7 2001FRCPC, Tania J. Phillips MD Background. Venous ulcers affect as many as 2.5 million people in the United States and can cause substantial pain and loss of function. Objective. To review current approaches to venous ulcers and compression. Method. Treatment options that have been proposed in the literature are discussed utilizing the Cochrane library database, Medline, and the author's clinical experience. Results. Diagnostic findings and management strategies for venous ulcers are reviewed. Conclusion. Good wound care and compression therapy will heal the majority of small venous ulcers of short duration. For ulcers that are slow to heal, other approaches such as venous surgery and grafting with conventional or bioengineered skin substitutes should be considered. [source] Reactive species and early manifestation of insulin resistance in type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 2 2006L. E. Fridlyand The early stages of type 2 diabetes mellitus are characterized by the development of insulin resistance (IRe) in muscle cells and adipocytes with the concomitant loss of ,-cell compensation. We have extensively reviewed the literature related to metabolic and signalling pathways of reactive oxygen species (ROS) in regard to the coordinated development of oxidative stress and IRe. We considered the hypothesis that oxidative stress leads to IRe in muscle cells and adipocytes, but found that the data are more consistent with the hypothesis that the cellular mechanisms that protect against oxidative stress per se are capable of creating an ROS-dependent insulin-resistant state. Furthermore, ROS-induced mitochondrial dysfunction can lead to disruptions of lipid metabolism, increasing the intracellular lipid content, and, in addition, contribute to lipid-dependent IRe in myocytes. Together, these two ROS-activated pathways to IRe can contribute to a global state of profound resistance to insulin action. Therapeutic strategies should, therefore, be directed towards reducing insulin resistance without an increase in ROS production or concentration. Pharmacological or other approaches to IRe that result in the activation of mitochondrial biogenesis in particular could be highly beneficial in the prevention or treatment of both insulin resistance and type 2 diabetes. [source] Survey of dietetic provision for patients with diabetesDIABETIC MEDICINE, Issue 8 2000M. Nelson SUMMARY Aims To survey dietitians involved in diabetes care regarding the provisions for patients with diabetes. Methods A national survey of 512 dietitians known to be engaged in provision of diabetes care was conducted in 1997 and 391 (76%) responded. Results Nationally the median provision of dietetic care for diabetes reported was 10.7 h per 100 000 general population per week, but the provision was uneven ranging from 2.0 to 27.6 h per 100 000. Eighty-five per cent of dietitians worked in areas where the provision was less than 22 h per 100 000 general population per week (the current recommended minimum standard). Dietetic provision was greater in secondary care (median 9.1 h per 100 000 general population per week) than in general practice, residential homes and other locations (median 4.4 h per 100 000 general population per week). Provision was greater in those areas in which a designated dietitian had responsibility for co-ordinating the dietetic service for diabetes than in areas where the co-ordinator was not a dietitian or where there was no co-ordinator. Over 90% of dietitians reported following British Diabetic Association (BDA) recommendations regarding advice on carbohydrate, sugar, fat and fibre consumption, but only one-third routinely advised on salt restriction. Of the 17% of dietitians who continue to use carbohydrate exchanges, all combine this method with other approaches. Of the recommendations made by the Clinical Standards Group, only 69% of dietitians reported seeing more than half of newly diagnosd adult patients within four weeks, and less than 50% reported offering half or more of their patients an annual review. Amongst the literature in current use, 98% of dietitians use BDA literature for teaching patients and 90% use BDA publications in their own education. Seventy-six per cent of dietitians believed that there was a role for commercial slimming organizations in weight management of people with diabetes Conclusions Given the proven value of dietetic input in diabetes management, there would be advantages to correcting the regional inequalities in dietetic provision for diabetes care in the UK. [source] REDUCING THE RISK OF PERISTOMAL INFECTION AFTER PEG PLACEMENTDIGESTIVE ENDOSCOPY, Issue 4 2005Iruru Maetani Percutaneous endoscopic gastrostomy (PEG) was first described in 1980 as an effective means of enteral nutrition where oral intake is not possible. PEG placement is safe and has now replaced the nasogastric tube in patients who need long-term feeding. Although it is relatively safe with a very low associated mortality, minor complications, especially local and systemic infection, remain a problem. Of these, peristomal wound infections are the most common complication of PEG. In patients indicated for this procedure who are aged and/or frail, this complication may pose a critical problem. In the commonly used pull or push methods for PEG placement, the PEG tube is readily colonized by oropharyngeal bacteria. Infection of the PEG site is considered to be associated with contamination of the PEG catheter. There are important measures that should be taken to prevent peristomal infection. A number of rigorous studies have shown that prophylactic antibiotics are effective in reducing the risk of peristomal infection. As methicillin-resistant Staphylococcus aureus (MRSA) or other resistant organisms are emerging as a major pathogen in peristomal infection, however, currently recommended antibiotic prophylaxis regimens might be inappropriate. Alternative regimens and other approaches to prevent contamination of the PEG tube during the procedure are required. [source] Technology and innovation in the psychosocial treatment of methamphetamine use, risk and dependenceDRUG AND ALCOHOL REVIEW, Issue 3 2008FRANCES J. KAY-LAMBKIN Abstract Issues. The dramatic increase in methamphetamine use has led to the urgent need for high-quality, effective treatments and management strategies for methamphetamine use problems to be developed and disseminated. Although some evidence exists for the use of psychological, pharmacological and other approaches to treatment for problematic methamphetamine use, other evidence suggests that many methamphetamine users do not access these treatment options due to a range of individual and service-level barriers. Approach. A review of available research literature was undertaken to identify treatment strategies for methamphetamine users, which overcome the problems associated with treatment access for this important target group and involve technological and other innovative approaches. Key Findings. Several approaches to addressing problematic methamphetamine use have been suggested, including assertive engagement strategies, flexibility in the provision of treatment and retention strategies and use of a multi-focused intervention package, such as stepped care, perhaps including new technologies as alternatives or supplements to face-to-face-delivered treatments. No research currently exists to examine the possible benefit of these strategies for people with methamphetamine use problems. Implications. The use of stepped-care intervention packages has the potential to address many of the current challenges faced by both clinicians and clients in treating methamphetamine use problems. Conclusions. Although promising, these approaches require further attention and research effort, particularly among the specific group of methamphetamine users. [source] Long-term landscape evolution: linking tectonics and surface processesEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2007Paul Bishop Abstract Research in landscape evolution over millions to tens of millions of years slowed considerably in the mid-20th century, when Davisian and other approaches to geomorphology were replaced by functional, morphometric and ultimately process-based approaches. Hack's scheme of dynamic equilibrium in landscape evolution was perhaps the major theoretical contribution to long-term landscape evolution between the 1950s and about 1990, but it essentially ,looked back' to Davis for its springboard to a viewpoint contrary to that of Davis, as did less widely known schemes, such as Crickmay's hypothesis of unequal activity. Since about 1990, the field of long-term landscape evolution has blossomed again, stimulated by the plate tectonics revolution and its re-forging of the link between tectonics and topography, and by the development of numerical models that explore the links between tectonic processes and surface processes. This numerical modelling of landscape evolution has been built around formulation of bedrock river processes and slope processes, and has mostly focused on high-elevation passive continental margins and convergent zones; these models now routinely include flexural and denudational isostasy. Major breakthroughs in analytical and geochronological techniques have been of profound relevance to all of the above. Low-temperature thermochronology, and in particular apatite fission track analysis and (U,Th)/He analysis in apatite, have enabled rates of rock uplift and denudational exhumation from relatively shallow crustal depths (up to about 4 km) to be determined directly from, in effect, rock hand specimens. In a few situations, (U,Th)/He analysis has been used to determine the antiquity of major, long-wavelength topography. Cosmogenic isotope analysis has enabled the determination of the ,ages' of bedrock and sedimentary surfaces, and/or the rates of denudation of these surfaces. These latter advances represent in some ways a ,holy grail' in geomorphology in that they enable determination of ,dates and rates' of geomorphological processes directly from rock surfaces. The increasing availability of analytical techniques such as cosmogenic isotope analysis should mean that much larger data sets become possible and lead to more sophisticated analyses, such as probability density functions (PDFs) of cosmogenic ages and even of cosmogenic isotope concentrations (CICs). PDFs of isotope concentrations must be a function of catchment area geomorphology (including tectonics) and it is at least theoretically possible to infer aspects of source area geomorphology and geomorphological processes from PDFs of CICs in sediments (,detrital CICs'). Thus it may be possible to use PDFs of detrital CICs in basin sediments as a tool to infer aspects of the sediments' source area geomorphology and tectonics, complementing the standard sedimentological textural and compositional approaches to such issues. One of the most stimulating of recent conceptual advances has followed the considerations of the relationships between tectonics, climate and surface processes and especially the recognition of the importance of denudational isostasy in driving rock uplift (i.e. in driving tectonics and crustal processes). Attention has been focused very directly on surface processes and on the ways in which they may ,drive' rock uplift and thus even influence sub-surface crustal conditions, such as pressure and temperature. Consequently, the broader geoscience communities are looking to geomorphologists to provide more detailed information on rates and processes of bedrock channel incision, as well as on catchment responses to such bedrock channel processes. More sophisticated numerical models of processes in bedrock channels and on their flanking hillslopes are required. In current numerical models of long-term evolution of hillslopes and interfluves, for example, the simple dependency on slope of both the fluvial and hillslope components of these models means that a Davisian-type of landscape evolution characterized by slope lowering is inevitably ,confirmed' by the models. In numerical modelling, the next advances will require better parameterized algorithms for hillslope processes, and more sophisticated formulations of bedrock channel incision processes, incorporating, for example, the effects of sediment shielding of the bed. Such increasing sophistication must be matched by careful assessment and testing of model outputs using pre-established criteria and tests. Confirmation by these more sophisticated Davisian-type numerical models of slope lowering under conditions of tectonic stability (no active rock uplift), and of constant slope angle and steady-state landscape under conditions of ongoing rock uplift, will indicate that the Davis and Hack models are not mutually exclusive. A Hack-type model (or a variant of it, incorporating slope adjustment to rock strength rather than to regolith strength) will apply to active settings where there is sufficient stream power and/or sediment flux for channels to incise at the rate of rock uplift. Post-orogenic settings of decreased (or zero) active rock uplift would be characterized by a Davisian scheme of declining slope angles and non-steady-state (or transient) landscapes. Such post-orogenic landscapes deserve much more attention than they have received of late, not least because the intriguing questions they pose about the preservation of ancient landscapes were hinted at in passing in the 1960s and have recently re-surfaced. As we begin to ask again some of the grand questions that lay at the heart of geomorphology in its earliest days, large-scale geomorphology is on the threshold of another ,golden' era to match that of the first half of the 20th century, when cyclical approaches underpinned virtually all geomorphological work. Copyright © 2007 John Wiley & Sons, Ltd. [source] Connections between species diversity and genetic diversityECOLOGY LETTERS, Issue 7 2005Mark Vellend Abstract Species diversity and genetic diversity remain the nearly exclusive domains of community ecology and population genetics, respectively, despite repeated recognition in the literature over the past 30 years of close parallels between these two levels of diversity. Species diversity within communities and genetic diversity within populations are hypothesized to co-vary in space or time because of locality characteristics that influence the two levels of diversity via parallel processes, or because of direct effects of one level of diversity on the other via several different mechanisms. Here, we draw on a wide range of studies in ecology and evolution to examine the theoretical underpinnings of these hypotheses, review relevant empirical literature, and outline an agenda for future research. The plausibility of species diversity,genetic diversity relationships is supported by a variety of theoretical and empirical studies, and several recent studies provide direct, though preliminary support. Focusing on potential connections between species diversity and genetic diversity complements other approaches to synthesis at the ecology,evolution interface, and should contribute to conceptual unification of biodiversity research at the levels of genes and species. [source] Achieving Quality in Clinical Decision Making: Cognitive Strategies and Detection of BiasACADEMIC EMERGENCY MEDICINE, Issue 11 2002Pat Croskerry MD Clinical decision making is a cornerstone of high-quality care in emergency medicine. The density of decision making is unusually high in this unique milieu, and a combination of strategies has necessarily evolved to manage the load. In addition to the traditional hypothetico-deductive method, emergency physicians use several other approaches, principal among which are heuristics. These cognitive short-cutting strategies are especially adaptive under the time and resource limitations that prevail in many emergency departments (EDs), but occasionally they fail. When they do, we refer to them as cognitive errors. They are costly but highly preventable. It is important that emergency physicians be aware of the nature and extent of these heuristics and biases, or cognitive dispositions to respond (CDRs). Thirty are catalogued in this article, together with descriptions of their properties as well as the impact they have on clinical decision making in the ED. Strategies are delineated in each case, to minimize their occurrence. Detection and recognition of these cognitive phenomena are a first step in achieving cognitive de-biasing to improve clinical decision making in the ED. [source] An efficient hybrid evolutionary algorithm based on PSO and ACO for distribution feeder reconfigurationEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 5 2010Taher Niknam Abstract A new formulation based on norm2 method for the multi objective distribution feeder reconfiguration (DFR) is introduced in order to minimize the real power loss, deviation of the nodes' voltage, the number of switching operations, and to balance the loads on the feeders. In the proposed method, since the objective functions are not the same and commensurable, the objective functions are considered as a vector and the aim is to maximize the distance (norm2) between the objective function vector and the worst objective function vector while the constraints are met. The status of the tie and sectionalizing switches are considered as the control variables. The proposed DFR problem is a multi objective and non-differentiable optimization problem so a hybrid evolutionary algorithm based on Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO), called HPSO, is proposed to solve it. The feasibility of the HPSO algorithm and the proposed DFR is demonstrated and compared with the solutions obtained by other approaches and evolutionary methods such as genetic algorithm (GA), ACO and the original PSO, over different distribution test systems. Copyright © 2009 John Wiley & Sons, Ltd. [source] ESTIMATING A GEOGRAPHICALLY EXPLICIT MODEL OF POPULATION DIVERGENCEEVOLUTION, Issue 3 2007L. Lacey Knowles Patterns of genetic variation can provide valuable insights for deciphering the relative roles of different evolutionary processes in species differentiation. However, population-genetic models for studying divergence in geographically structured species are generally lacking. Since these are the biogeographic settings where genetic drift is expected to predominate, not only are population-genetic tests of hypotheses in geographically structured species constrained, but generalizations about the evolutionary processes that promote species divergence may also be potentially biased. Here we estimate a population-divergence model in montane grasshoppers from the sky islands of the Rocky Mountains. Because this region was directly impacted by Pleistocene glaciation, both the displacement into glacial refugia and recolonization of montane habitats may contribute to differentiation. Building on the tradition of using information from the genealogical relationships of alleles to infer the geography of divergence, here the additional consideration of the process of gene-lineage sorting is used to obtain a quantitative estimate of population relationships and historical associations (i.e., a population tree) from the gene trees of five anonymous nuclear loci and one mitochondrial locus in the broadly distributed species Melanoplus oregonensis. Three different approaches are used to estimate a model of population divergence; this comparison allows us to evaluate specific methodological assumptions that influence the estimated history of divergence. A model of population divergence was identified that significantly fits the data better compared to the other approaches, based on per-site likelihood scores of the multiple loci, and that provides clues about how divergence proceeded in M. oregonensis during the dynamic Pleistocene. Unlike the approaches that either considered only the most recent coalescence (i.e., information from a single individual per population) or did not consider the pattern of coalescence in the gene genealogies, the population-divergence model that best fits the data was estimated by considering the pattern of gene lineage coalescence across multiple individuals, as well as loci. These results indicate that sampling of multiple individuals per population is critical to obtaining an accurate estimate of the history of divergence so that the signal of common ancestry can be separated from the confounding influence of gene flow,even though estimates suggest that gene flow is not a predominant factor structuring patterns of genetic variation across these sky island populations. They also suggest that the gene genealogies contain information about population relationships, despite the lack of complete sorting of gene lineages. What emerges from the analyses is a model of population divergence that incorporates both contemporary distributions and historical associations, and shows a latitudinal and regional structuring of populations reminiscent of population displacements into multiple glacial refugia. Because the population-divergence model itself is built upon the specific events shaping the history of M. oregonensis, it provides a framework for estimating additional population-genetic parameters relevant to understanding the processes governing differentiation in geographically structured species and avoids the problems of relying on overly simplified and inaccurate divergence models. The utility of these approaches, as well as the caveats and future improvements, for estimating population relationships and historical associations relevant to genetic analyses of geographically structured species are discussed. [source] Teaching Sensitivity to Cultural Difference in the First-Year Foreign Language ClassroomFOREIGN LANGUAGE ANNALS, Issue 1 2007Article first published online: 31 DEC 200, Dennis O. Durocher Jr. Abstract: This article summarizes teacher action research for the teaching of subjective culture in the foreign language classroom. It begins with a literature review, followed by a description of Milton J. Bennett's Developmental Model of Intercultural Sensitivity (Bennett, 1993), the theoretical paradigm upon which classroom activities and experiments were based. Bennett's model is compared and contrasted with other approaches to teaching culture, its strengths and weaknesses are discussed, and suggestions for implementing the model are presented. The article then summarizes efforts to mobilize the theory at the elementary French level, describes various culture-teaching strategies, and presents the results of evaluations of the effectiveness of the strategies using the Intercultural Development Inventory. Final remarks concern the goals of the culture component in the foreign language curriculum and suggestions for next steps in research. [source] A partial least-square approach for modeling gene-gene and gene-environment interactions when multiple markers are genotypedGENETIC EPIDEMIOLOGY, Issue 1 2009Tao Wang Abstract Genetic association studies achieve an unprecedented level of resolution in mapping disease genes by genotyping dense single nucleotype polymorphisms (SNPs) in a gene region. Meanwhile, these studies require new powerful statistical tools that can optimally handle a large amount of information provided by genotype data. A question that arises is how to model interactions between two genes. Simply modeling all possible interactions between the SNPs in two gene regions is not desirable because a greatly increased number of degrees of freedom can be involved in the test statistic. We introduce an approach to reduce the genotype dimension in modeling interactions. The genotype compression of this approach is built upon the information on both the trait and the cross-locus gametic disequilibrium between SNPs in two interacting genes, in such a way as to parsimoniously model the interactions without loss of useful information in the process of dimension reduction. As a result, it improves power to detect association in the presence of gene-gene interactions. This approach can be similarly applied for modeling gene-environment interactions. We compare this method with other approaches, the corresponding test without modeling any interaction, that based on a saturated interaction model, that based on principal component analysis, and that based on Tukey's one-degree-of-freedom model. Our simulations suggest that this new approach has superior power to that of the other methods. In an application to endometrial cancer case-control data from the Women's Health Initiative, this approach detected AKT1 and AKT2 as being significantly associated with endometrial cancer susceptibility by taking into account their interactions with body mass index. Genet. Epidemiol. 2008. © 2008 Wiley-Liss, Inc. [source] The sedimentary records in Mediterranean rockshelters and caves: Archives of environmental changeGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 4 2001Jamie C. Woodward It is important to develop rigorous methods and robust conceptual models for the interpretation of rockshelter and cave sediment records so that the cultural sequences they contain can be considered in their proper environmental context. Much of what we know about the prehistory of the Mediterranean region and adjacent areas has largely been pieced together from materials excavated from sedimentary sequences in these environments. The rockshelters and caves of the region form important environmental and sedimentary archives. Recent work has begun to consider if the remarkable climatic variability evident in the high resolution lacustrine and ice core records is manifest in the rockshelter and cave sediment records of the area. In this context, the two main characteristics of a rockshelter or cave site which control its usefulness as an archive of environmental change are the temporal resolution of the sedimentary record and the environmental sensitivity of the site. Many rockshelters and caves can be described as either Active Karst Settings (AKS) or Passive Karst Settings (PKS) and site type is an important influence on climatic sensitivity with a direct influence upon the usefulness of the sedimentary sequence as a proxy record of climate change. It is now clear that some sites may preserve detailed paleoclimatic records and the climatic signal may be represented by distinctive suites of micromorphological features, by variations in the input of allogenic sediment, or by fluctuations in the mineral magnetic properties of the fine sediment fraction. It can be argued that data derived from the analysis of bulk coarse-grained samples often lacks the stratigraphic resolution and environmental sensitivity that can be obtained from other approaches. The most favorable sites for detailed paleoclimatic reconstruction appear to be in active karst settings such as Theopetra Cave (Greece) and Pigeon Cave (Morocco) where micromorphological analyses offer insights into the stratigraphic record that are not otherwise obtainable. The temporal resolution of a site can only be established through a rigorous stratigraphic analysis and a comprehensive dating program. These are fundamental considerations in the study of rockshelter sediment records, especially when attempting to correlate between sites and draw comparisons with other proxy records of environmental change derived from sedimentary environments with rather different characteristics. Rockshelters and caves are part of a wider sediment system, and their investigation must be accompanied by detailed geomorphological, sedimentological, paleoecological, and geochronological studies of the off-site Quaternary record. © 2001 John Wiley & Sons, Inc. [source] DNAPL Characterization Methods and Approaches, Part 2: Cost ComparisonsGROUND WATER MONITORING & REMEDIATION, Issue 1 2002Mark L. Kram Contamination from the use of chlorinated solvents, often classified as dense nonaqueous phase liquids (DNAPLs) when in an undissolved state, pose environmental threats to ground water resources worldwide. DNAPL site characterization method performance comparisons are presented in a companion paper (Kram et al. 2001). This study compares the costs for implementing various characterization approaches using synthetic unit model scenarios (UMSs), each with particular physical characteristics. Unit costs and assumptions related to labor, equipment, and consumables are applied to determine costs associated with each approach for various UMSs. In general, the direct-push sensor systems provide cost-effective characterization information in soils that are penetrable with relatively shallow (less than 10 to 15 m) water tables. For sites with impenetrable lithology using direct-push techniques, the Ribbon NAPL Sampler Flexible Liner Underground Technologies Everting (FLUTe) membrane appears to be the most cost-effective approach. For all scenarios studied, partitioning interwell tracer tests (PITTs) are the most expensive approach due to the extensive pre-and post-PITT requirements. However, the PITT is capable of providing useful additional information, such as approximate DNAPL saturation, which is not generally available from any of the other approaches included in this comparison. [source] Craniofacial resection for tumors of the nasal cavity and paranasal sinuses: A 25-year experienceHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 10 2006David J. Howard FRCS, FRCS(Ed) Abstract Background. Craniofacial resection is the established "gold standard" for surgical treatment of tumors affecting the anterior skull base. Methods. This study analyzed 308 patients (220 males, 88 females) who had undergone craniofacial resection for sinonasal neoplasia with up to 25-year follow-up. Results. An overall actuarial survival of 65% at 5 years and 47% at 10 years was found for the cohort as a whole. For patients with malignant tumors, the 5-year actuarial survival was 59%, falling to 40% at 10 years. For patients with benign pathology, the actuarial survival was 92% at 5 years falling to 82% at 10 years. Statistical analysis again identified brain involvement, type of malignancy, and orbital involvement as the 3 most significant prognostic factors. Conclusion. Analysis of one of the largest single institution cohorts over a 25-year period provides a baseline against which other approaches such as an entirely endoscopic skull base resection must be judged. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] A preference-based index for the SF-12HEALTH ECONOMICS, Issue 6 2006D. Stratmann-Schoene Abstract Background: The SF-12 is a widely used generic measure of subjective health. As the scoring algorithms of the SF-12 do not include preference values, different approaches to assign a preference-based index are available that should be tested regarding their feasibility and validity. Objectives: To develop a concept for a preference-based index for the SF-12 on the basis of multi-attribute decision analysis and to perform initial tests of its feasibility and validity in an empirical study. Methods: A multi-attribute preference function for the SF-12 was developed, estimated and tested for validity. Two mail surveys (n = 100, 200) and an interview (n = 72) were conducted with women who had an operation for breast cancer. Visual analogue scale (VAS) and standard gamble (SG) measures elicited preference-based valuations. Results: Eight attributes were identified in the SF-12. Validity tests showed an average difference of 8 VAS score points between directly measured and predicted values for given health states. Conclusion: The initial results show that this approach might allow the direct assignment of a preference-based valuation to the SF-12. The quality of the psychometric features of the multi-attribute value function is encouraging. Future studies should test this concept more extensively, especially by determining parameters for a representative sample of the general population and by comparing performance with other approaches to value the SF-12. Copyright © 2005 John Wiley & Sons, Ltd. [source] Mythico-History, Social Memory, and Praxis: Anthropological Approaches and DirectionsHISTORY COMPASS (ELECTRONIC), Issue 3 2009Susan Rasmussen This article explores the interface and tension between myth, history, and memory, in relation to ideology and praxis of identity. There is a critical overview of anthropological and other approaches in the humanities and social sciences to ,mythico-history' and social memory, their mutual influences, and current debates and directions in this literature. In particular, emphasis is upon the uses of oral narratives in historiography and social context in the constructions of personal and collective identities of difference, for example, ethnicity and gender in ,narratives of nation' and ,myths of matriliny' and their connections to social practice, drawing on secondary cross-cultural data and primary data from this anthropologist's research in Tuareg (Kel Tamajaq) communities of northern Niger and Mali. [source] Vertical dynamic response of a rigid foundation embedded in a poroelastic soil layerINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 11 2009Y. Q. Cai Abstract A simplified analytical method is presented for the vertical dynamic analysis of a rigid, massive, cylindrical foundation embedded in a poroelastic soil layer. The foundation is subjected to a time-harmonic vertical loading and is perfectly bonded to the surrounding soil in the vertical direction. The soil underlying the foundation base is represented by a single-layered poroelastic soil based on rigid bedrock while the soil at the side of the foundation is modeled as an independent poroelastic layer composed of a series of infinitesimally thin layers. The behavior of the soil is governed by Biot's poroelastodynamic theory and its governing equations are solved by the use of Hankel integral transform. The contact surface between the foundation base and the soil is smooth and fully permeable. The dynamic interaction problem is solved following standard numerical procedures. The accuracy of the present solution is verified by comparisons with the well-known solutions obtained from other approaches for both the elastodynamic interaction problem and poroelastodynamic interaction problem. Numerical results for the vertical dynamic impedance and response factor of the foundation are presented to demonstrate the influence of nondimensional frequency of excitation, soil layer thickness, poroelastic material parameters, depth ratio and mass ratio on the dynamic response of a rigid foundation embedded in a poroelastic soil layer. Copyright © 2008 John Wiley & Sons, Ltd. [source] Direct, partitioned and projected solution to finite element consolidation modelsINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 14 2002Giuseppe Gambolati Abstract Direct, partitioned, and projected (conjugate gradient-like) solution approaches are compared on unsymmetric indefinite systems arising from the finite element integration of coupled consolidation equations. The direct method is used in its most recent and computationally efficient implementations of the Harwell Software Library. The partitioned approach designed for coupled problems is especially attractive as it addresses two separate positive definite problems of a smaller size that can be solved by symmetric conjugate gradients. However, it may stagnate and when converging it does not prove competitive with a global projection method such as Bi-CGSTAB, which may take full advantage of its flexibility in working on scaled and reordered equations, and thus may greatly improve its computational performance in terms of both robustness and convergence rate. The Bi-CGSTAB superiority to the other approaches is discussed and demonstrated with a few representative examples in two-dimensional (2-D) and three-dimensional (3-D) coupled consolidation problems. Copyright © 2002 John Wiley & Sons, Ltd. [source] Cyclical long-range dependence and the warming effect in a long temperature time seriesINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 11 2008L. A. Gil-Alana Abstract In this paper, we propose a new approach for modelling a long temperature time series, using fractional cyclical integration. This model is based on the observation that the estimated spectrum of the series (the average annual temperature in Central England, 1659,2001) has its highest value at a frequency which is not zero, thus suggesting the existence of cycles at other frequencies. The results based on a fractional cyclical model show that there is a significant warming effect throughout the sample of about 0.22 °C/century. However, if we concentrate exclusively on the data corresponding to the 20th century that value increases to 0.64%. Moreover, the results in the paper show that a fractionally cyclically integrated model can be a competing alternative to other approaches based on fractional integration at the zero frequency. Copyright © 2007 Royal Meteorological Society [source] Selective partial PIC for wireless CDMA communicationsINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 6 2003Filippo Belloni Abstract This paper deals with a cancellation multiuser detector for CDMA communication systems. The proposed receiver, defined as selective partial parallel interference cancellation (SP-PIC), is supposed to be used at the end of an up-link channel characterized by multipath fading phenomena. The SP-PIC main feature is to perform a weighted selective cancellation of the co-channel interfering signals according to the received power level. With respect to other approaches, the proposed detector exhibits an improved bit error rate (BER) and a low computational complexity, linear with the number of users. Copyright © 2003 John Wiley & Sons, Ltd. [source] Learning weighted linguistic rules to control an autonomous robotINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 3 2009M. Mucientes A methodology for learning behaviors in mobile robotics has been developed. It consists of a technique to automatically generate input,output data plus a genetic fuzzy system that obtains cooperative weighted rules. The advantages of our methodology over other approaches are that the designer has to choose the values of only a few parameters, the obtained controllers are general (the quality of the controller does not depend on the environment), and the learning process takes place in simulation, but the controllers work also on the real robot with good performance. The methodology has been used to learn the wall-following behavior, and the obtained controller has been tested using a Nomad 200 robot in both simulated and real environments. © 2009 Wiley Periodicals, Inc. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||