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Selected AbstractsSurface deformation due to loading of a layered elastic half-space: a rapid numerical kernel based on a circular loading elementGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2007E. Pan SUMMARY This study is motivated by a desire to develop a fast numerical algorithm for computing the surface deformation field induced by surface pressure loading on a layered, isotropic, elastic half-space. The approach that we pursue here is based on a circular loading element. That is, an arbitrary surface pressure field applied within a finite surface domain will be represented by a large number of circular loading elements, all with the same radius, in which the applied downwards pressure (normal stress) is piecewise uniform: that is, the load within each individual circle is laterally uniform. The key practical requirement associated with this approach is that we need to be able to solve for the displacement field due to a single circular load, at very large numbers of points (or ,stations'), at very low computational cost. This elemental problem is axisymmetric, and so the displacement vector field consists of radial and vertical components both of which are functions only of the radial coordinate r. We achieve high computational speeds using a novel two-stage approach that we call the sparse evaluation and massive interpolation (SEMI) method. First, we use a high accuracy but computationally expensive method to compute the displacement vectors at a limited number of r values (called control points or knots), and then we use a variety of fast interpolation methods to determine the displacements at much larger numbers of intervening points. The accurate solutions achieved at the control points are framed in terms of cylindrical vector functions, Hankel transforms and propagator matrices. Adaptive Gauss quadrature is used to handle the oscillatory nature of the integrands in an optimal manner. To extend these exact solutions via interpolation we divide the r -axis into three zones, and employ a different interpolation algorithm in each zone. The magnitude of the errors associated with the interpolation is controlled by the number, M, of control points. For M= 54, the maximum RMS relative error associated with the SEMI method is less than 0.2 per cent, and it is possible to evaluate the displacement field at 100 000 stations about 1200 times faster than if the direct (exact) solution was evaluated at each station; for M= 99 which corresponds to a maximum RMS relative error less than 0.03 per cent, the SEMI method is about 700 times faster than the direct solution. [source] Caterers' experiences and perceptions of implementing the 2006 school meal standardsJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2008C.J. Weir Background:, School meal standards were introduced in 2006 (Department for Education and Skills) and caterers are expected to comply with these standards. No research has been conducted looking at the caterer's experiences and perceptions of implementing these standards. This area has 32 school meal provider organisations for 103 schools. Half the schools are with one provider and the others are, mostly, single-handed in-house operations, often managed by a local community member. The aim of the current study was to explore caterers' understanding of the school meal standards, the barriers to implementation, and proposed solutions, to inform local practice. Methods:, A combined quantitative and qualitative design was used. A questionnaire was used to assess understanding and implementation of the standards and distributed to all the catering provider organisations (n = 32), with a good response rate of 78% (n = 25). For each question about achievement of the ten food-based standards the responses were scored 0,4 where: 0 = ,Do not intend to achieve this standard'; to 4 = ,Fully achieved'. This gave a total standards achievement score for each catering provider organisation, where the minimum score that could be achieved was zero which indicated the minimum level of achievement and the maximum score which could be achieved was forty which indicated all ten standards fully achieved. Four focus group were undertaken involving 40 people who considered themselves to be in a management role within a catering provider organisation. Semi structured interviews were undertaken with 11 people (until saturation), using purposive sampling, to explore barriers and solutions to implementation of the standards in detail. Descriptive and appropriate inferential statistics (Fisher's Exact tests and independent samples t- tests) were performedon the datausingStatistical Package for Social Sciences (SPSS). The process undertaken for the qualitative analysis was thematic analysis, and used analytic hierarchy (Richie & Lewis, 2003). Approval for this study was obtained from Leeds Metropolitan University ethics committee. Results:, The qualitative discussions led to caterers' identifying two main themes. These were: support from various groups, and the roles and responsibilities caterers believed these groups had and should be performing in order to achieve successful implementation of the standards ,Think it's good someone's shaken up school meals but who is doing the actually work , it's us isn't it'.(Semi structured interview respondent medium primary provider) ,I've found it really difficult as I'm on my own at the school, totally on my own without anyone to help'. (Focus group participant primary school group). The groups that caterers identified as those who had roles and responsibilities and who should be providing support were the ,whole school'; catering provider organisations; parents; the local authority; and, the broader environment/whole population. Caterers felt the standards had ,gone too far too soon' and did not allow choice. Caterers felt finances were a barrier, and that training was required across all sectors to achieve success. The standards implementation achievement score were statistically higher for caterers who had received formal training compared with those with only food and hygiene (P = 0.001); and, between caterers who provided to a secondary school as opposed to a primary school only (P = 0.034). There was a statistically significant relationship between providers and qualifications with those providing to secondary schools more likely to have had formal qualifications (P = 0.015). Discussion:, Caterers felt all those involved in schools and school meals needed to undertake their roles and responsibilities, to provide support, and, to implement the ethos of a whole school approach. The caterers in this study identified many barriers and practical obstacles either experienced or perceived to implementing the new school meals standards. Conclusions:, The results will be used to inform the Local Authority and Primary Care Trust to ensure the effective implementation of the school meal standards. There may be opportunity to transfer these results to other school caterers, and to develop support and training to assist implementation. [source] Children's perceptions of who controls their foodJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2000S. Robinson Background The purpose of this study was to explore children's perceptions of who controlled the quality and quantity of their food during the week. Methods Semi structured interviews were carried out with 98 9-year-old children. The children were asked to describe who chose what they ate during a typical week day. They were also asked about who decided how much they ate. Results The children thought that adults had a high degree of control over their food. They frequently reported that either they were allowed to choose from a selection provided by an adult, or that an adult chose their food without consultation. Many children reported that adults were very influential in determining how much food they ate. Conclusions Although the children thought that adults imposed control upon their food choices, it is argued that children have more choice about their food than at any time in history. The children's perceptions highlight the need for planned dietary change to acknowledge the various influences which can affect choices of children's food. [source] Responses of Aquatic Macrophytes to Disturbance by Flash Floods in a Brazilian Semiarid Intermittent Stream,BIOTROPICA, Issue 4 2001Leonardo Maltchik ABSTRACT Resistance and resilience of Najas marina to disturbance by flash floods were studied in a permanent fluvial pool of a Brazilian semiarid intermittent stream. A total of 21 macrophyte samples was collected in the high-rainfall season during two annual cycles (1996,1997). Decreases in macrophyte biomass were positively correlated with flood magnitude (Pearson, P = 0.047), varying from 25 to 53 percent when discharges were lower than or equal to 0.5 m3/ sec and between 70 and 100 percent when discharges were higher than 1.0 m- 3/sec. Macrophyte resilience was greater after floods of low magnitude. After floods of 0.5 m- 3/sec, three weeks were necessary to re-establish 88 percent of biomass lost, and after a flood of 1.4 m-Vsec, six months were needed to initiate A, marina regrowth. This population of N. marina in Avelós stream has higher stability in response to small disturbances, but as expected, its resistance and resilience decreases with larger disturbances. In general, the high resistance and resilience of N. marina m response to small disturbances have been observed in intermittent tropical streams. The absence of large floods during the study period and the low variability of water temperature in this tropical region may have influenced these results. RESUMES A influencia de cheias rápidas na resistência e na resistência de Najas marina foram estudadas em uma poça fluvial permanente de um riacho efêmero do Semi-árido Brasileiro. Vinte e uma coletas de macrófitas aquáticas foram realizadas durante o período de chuvas de dois ciclos anuais (1996 e 1997). A variaçäo da biomassa de macrófitas aquáticas estava diretamente correlacionada com a magnitude da cheia (Pearson, P=0.047), variando entre 25 e 53 por cento quando as vazöes eram inferiores ou iguais à 0.5 m3 -Vsec e entre 70 e 100 por cento quando as vazöes eram superiores à 1.0 m3/sec. A resiliência de macrófitas era maior após às cheias de baixa magnitude. Após a cheia de 0.5 m3 -Vsec, foram necessários seis meses para restabelecer 88 por cento da biomassa perdida, e após a cheia de 1.4 m3/ sec, foram necessáries seis meses para iniciar a resiliência de Najas marina. Esta populaçäo de N. marina do riacho Avelós apresentou maior estabilidade frente ás perturbaçöes hidrológicas de baixa magnitude, mas a resistêncía e a resiliéncia diminuíam à medida que a magnitude da perturbaçao aumentava. A alta resístência e resiliência de N marina frente às perturbaçöes hidrológicas de baixa magnitude, geralmente tem sido observadas em riachos intermi-tentes tropicais. A ausência de grandes cheias durante o periodo estudado e a pequena amplitude térmica da água superficial desta regiäo tropical podem ter favorecido estes resultados. [source] Organizing for Continuous Innovation: On the Sustainability of Ambidextrous OrganizationsCREATIVITY AND INNOVATION MANAGEMENT, Issue 3 2005Bart Van Looy Organizing for innovation does not present itself as a straightforward exercise. The complexities entailed when implementing an innovation strategy can be related directly to the multitude of objectives it comprises. Recently, several scholars have advanced the notions of semi- or quasi-structures and ambidextrous organizations to handle these multiple requirements. These organizational forms imply the simultaneous presence of different activities, exhibiting differences in technology and market maturation. As a consequence, financial returns will reflect this diversified resource allocation pattern. Moreover, as higher levels of complexity are being introduced; ambidextrous organizations will encounter additional, organizational, costs. Compared to organizations that focus on the most profitable part of the portfolio, ambidextrous organizations , ceteris paribus , tend to be inferior in terms of financial returns. Within this contribution we explore under which conditions ambidextrous organizations can outperform focused firms; considered a prerequisite for their sustainability. In order to do so, we develop an analytical framework depicting the differential value dynamics, focused and ambidextrous firms can enact. Our findings reveal the relevancy of adopting extended time frames as well as introducing interface management practices aimed at cross-fertilization. Finally, the synergetic potential of (underlying) technologies comes to the forefront as necessary in order for ambidextrous organizations to become sustainable. [source] A Modeling Framework for Supply Chain Simulation: Opportunities for Improved Decision Making,DECISION SCIENCES, Issue 1 2005D. J. Van Der Zee ABSTRACT Owing to its inherent modeling flexibility, simulation is often regarded as the proper means for supporting decision making on supply chain design. The ultimate success of supply chain simulation, however, is determined by a combination of the analyst's skills, the chain members' involvement, and the modeling capabilities of the simulation tool. This combination should provide the basis for a realistic simulation model, which is both transparent and complete. The need for transparency is especially strong for supply chains as they involve (semi)autonomous parties each having their own objectives. Mutual trust and model effectiveness are strongly influenced by the degree of completeness of each party's insight into the key decision variables. Ideally, visual interactive simulation models present an important communicative means for realizing the required overview and insight. Unfortunately, most models strongly focus on physical transactions, leaving key decision variables implicit for some or all of the parties involved. This especially applies to control structures, that is, the managers or systems responsible for control, their activities and their mutual attuning of these activities. Control elements are, for example, dispersed over the model, are not visualized, or form part of the time-indexed scheduling of events. In this article, we propose an alternative approach that explicitly addresses the modeling of control structures. First, we will conduct a literature survey with the aim of listing simulation model qualities essential for supporting successful decision making on supply chain design. Next, we use this insight to define an object-oriented modeling framework that facilitates supply chain simulation in a more realistic manner. This framework is meant to contribute to improved decision making in terms of recognizing and understanding opportunities for improved supply chain design. Finally, the use of the framework is illustrated by a case example concerning a supply chain for chilled salads. [source] Treatment of erythema multiforme, Stevens,Johnson Syndrome, and toxic epidermal necrolysisDERMATOLOGIC THERAPY, Issue 4 2002Klemens Rappersberger The "erythema multiforme disease spectrum" comprises four distinct, severe, clinical subvariants: (1) bullous erythema multiforme (bullous-EM), (2) Stevens,Johnson syndrome (SJS), (3) SJS,toxic epidermal necrolysis (TEN)-overlap syndrome, and (4) TEN. These diseases are closely related to severe mucocutaneous intolerance reactions that are mostly elicited by drugs/drug metabolites and associated with a high mortality rate. Old age and area of detached skin negatively influence the course of disease, and early withdrawal of causative drugs with short half-life is a positive prognostic factor. Therapeutic management represents a multidisciplinary challenge for colleagues from various specialities including specialized nurses and usually can be performed at a dermatologic ward unless technical equipment of an intensive care unit is needed. Topical therapy with biologic and (semi-)synthetic dressings is aimed at early re-epithelialization and the prevention of scarring, synechia formation, and infection. Systemic treatment includes antibiotics, fluid and electrolyte replacement, protein preparations and blood products, etc. Various anti-inflammatory and immunosuppressive treatment regimens with corticosteroids, cyclosporine A, cyclophosphamide, plasmapheresis have been considered to halt ongoing immunologic pathomechanisms, and some of these have shown significant efficacy. However, because we lack formal clinical trials, none of these regimens can be definitively proposed as a therapy of choice in any of the severe clinical variants of the EM spectrum. [source] Methods for detecting and identifying retinoids in tissueDEVELOPMENTAL NEUROBIOLOGY, Issue 7 2006Thomas E. Gundersen Abstract Methods for retinoid analysis in tissue include direct spectrophotometry or fluorometry and retinoid responsive reporter constructs in the form of cell reporter assays or transgenic reporter animals, but chromatographic methods dominate and posses several superior features in quantitative analysis. The multitude of extraction protocols used can coarsely be divided into manual liquid-liquid extraction protocols and semi- or fully automated solid phase extraction-based protocols. Liquid chromatographic separation in reversed phase dominates although normal phase is also used. Detection is mainly performed with UV detectors although electrochemical and fluorescence detection is also used. Mass spectrometry in combination with LC is more often used in retinoid analysis and is likely to dominate in the future. © 2006 Wiley Periodicals, Inc. J Neurobiol 66: 631,644, 2006 [source] Below-ground competition between trees and grasses may overwhelm the facilitative effects of hydraulic liftECOLOGY LETTERS, Issue 8 2004F. Ludwig Abstract Under large East African Acacia trees, which were known to show hydraulic lift, we experimentally tested whether tree roots facilitate grass production or compete with grasses for below-ground resources. Prevention of tree,grass interactions through root trenching led to increased soil water content indicating that trees took up more water from the topsoil than they exuded via hydraulic lift. Biomass was higher in trenched plots compared to controls probably because of reduced competition for water. Stable isotope analyses of plant and source water showed that grasses which competed with trees used a greater proportion of deep water compared with grasses in trenched plots. Grasses therefore used hydraulically lifted water provided by trees, or took up deep soil water directly by growing deeper roots when competition with trees occurred. We conclude that any facilitative effect of hydraulic lift for neighbouring species may easily be overwhelmed by water competition in (semi-) arid regions. [source] Do dams increase genetic diversity in brown trout (Salmo trutta)?ECOLOGY OF FRESHWATER FISH, Issue 4 2006Microgeographic differentiation in a fragmented river Abstract , Local genetic differentiation may potentially arise in recently fragmented populations. Brown trout is a polytypic species exhibiting substantial genetic differentiation, which may evolve in few generations. Movement (semi-)barriers in rivers may cause fragmentation, isolation and genetic differentiation in fish. In the Måna River (28 km) flowing from the alpine Lake Møsvatn to the boreal Lake Tinnsjø, construction of four hydropower dams during the period 1906,1957 have fragmented the previously (since last Ice Age) continuous wild resident brown trout population. Samples from the two lakes (N = 40) and six sites in the river (N = 30) isolated at different times were analysed at nine microsatellite loci. All populations showed substantial genetic variation (mean number of alleles per locus 5.3,8.9, observed heterozygosity 0.57,0.65 per population, overall Fst = 0.032). Pairwise multilocus Fst estimates indicated no significant differentiation between populations in the two lakes, and no or little differentiation in the lower river (Fst = 0.0035,0.0091). The microgeographic differentiation among wild resident trout at these sites was less than expected based on similar previous studies. However, results from the upper river, in particular the site immediately below the Lake Møsvatn outlet and dam, indicated isolation (Fst > 0.035). Calculation of genetic distances and assignment tests corroborated these results, as did a significant correlation between years of isolation (since dam construction) and Fst. The population structuring is most likely a result of fragmentation by dams, which has increased overall genetic diversity. This increased local differentiation may be caused by natural selection, but more likely by genetic drift in small, recently fragmented populations. Increased local genetic diversity by genetic drift does not justify conservation measures aiming at preserving genetic diversity. [source] Characteristics of strawberry plants propagated by in vitro bioreactor culture and ex vitro propagation methodENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2009Samir C. Debnath Abstract Reproducible protocol for regeneration of complete plantlets from ,Bounty' strawberry (Fragaria ananassa Duch.), using a combination of gelled medium and bioreactor system, has been standardized. Sepals, leaf discs, and petiole halves produced multiple buds and shoots when cultured on semi solid-gelled medium containing 4 ,M thidiazuron (TDZ) for 4 wk followed by transferring in liquid medium containing 2,,M TDZ in a bioreactor system and cultured for another 4 wk. TDZ induced shoot proliferation at 0.1,,M in the bioreactor system but inhibited shoot elongation. TDZ-induced shoots were elongated and rooted in vitro on gelled medium containing 2,,M zeatin. Such bioreactor-derived tissue culture (BC) plantlets obtained from sepal explants were grown ex vitro and compared with those propagated by tissue culture on gelled medium (GC) and by conventional runner cuttings (RC), for growth, morphology, anthocyanin content, and antioxidant activity after three growth seasons. The BC and GC plants produced more crowns, runners, leaves, and berries than the RC plants although berry weight per plant did not differ significantly. BC and GC plants produced berries with more anthocyanin contents and antioxidant activities than those produced by the RC plants. However, intersimple sequence repeat (ISSR) marker assay produced a homogenous amplification profile in the tissue culture and donor control plants confirming the clonal fidelity of micropropagated plants. In vitro culture on TDZ and zeatin-containing nutrient media apparently induced the juvenile branching characteristics that favored enhanced vegetative growth with more crown, runners, leaf, and berry production. [source] Interpretation of observed fluid potential patterns in a deep sedimentary basin under tectonic compression: Hungarian Great Plain, Pannonian BasinGEOFLUIDS (ELECTRONIC), Issue 1 2001J. Tóth Abstract The , 40 000 km2 Hungarian Great Plain portion of the Pannonian Basin consists of a basin fill of 100 m to more than 7000 m thick semi- to unconsolidated marine, deltaic, lacustrine and fluviatile clastic sediments of Neogene age, resting on a strongly tectonized Pre-Neogene basement of horst-and-graben topography of a relief in excess of 5000 m. The basement is built of a great variety of brittle rocks, including flysch, carbonates and metamorphics. The relatively continuous Endr,d Aquitard, with a permeability of less than 1 md (10,15 m2) and a depth varying between 500 and 5000 m, divides the basin's rock framework into upper and lower sequences of highly permeable rock units, whose permeabilities range from a few tens to several thousands of millidarcy. Subsurface fluid potential and flow fields were inferred from 16 192 water level and pore pressure measurements using three methods of representation: pressure,elevation profiles; hydraulic head maps; and hydraulic cross-sections. Pressure,elevation profiles were constructed for eight areas. Typically, they start from the surface with a straight-line segment of a hydrostatic gradient (,st = 9.8067 MPa km,1) and extend to depths of 1400,2500 m. At high surface elevations, the gradient is slightly smaller than hydrostatic, while at low elevations it is slightly greater. At greater depths, both the pressures and their vertical gradients are uniformly superhydrostatic. The transition to the overpressured depths may be gradual, with a gradient of ,dyn = 10,15 MPa km,1 over a vertical distance of 400,1000 m, or abrupt, with a pressure jump of up to 10 MPa km,1 over less than 100 m and a gradient of ,dyn > 20 MPa km,1. According to the hydraulic head maps for 13 100,500 m thick horizontal slices of the rock framework, the fluid potential in the near-surface domains declines with depth beneath positive topographic features, but it increases beneath depressions. The approximate boundary between these hydraulically contrasting regions is the 100 m elevation contour line in the Duna,Tisza interfluve, and the 100,110 m contours in the Nyírség uplands. Below depths of ,,600 m, islets of superhydrostatic heads develop which grow in number, areal extent and height as the depth increases; hydraulic heads may exceed 3000 m locally. A hydraulic head ,escarpment' appears gradually in the elevation range of ,,1000 to ,,2800 m along an arcuate line which tracks a major regional fault zone striking NE,SW: heads drop stepwise by several hundred metres, at places 2000 m, from its north and west sides to the south and east. The escarpment forms a ,fluid potential bank' between a ,fluid potential highland' (500,2500 m) to the north and west, and a ,fluid potential basin' (100,500 m) to the south and east. A ,potential island' rises 1000 m high above this basin further south. According to four vertical hydraulic sections, groundwater flow is controlled by the topography in the upper 200,1700 m of the basin; the driving force is orientated downwards beneath the highlands and upwards beneath the lowlands. However, it is directed uniformly upwards at greater depths. The transition between the two regimes may be gradual or abrupt, as indicated by wide or dense spacing of the hydraulic head contours, respectively. Pressure ,plumes' or ,ridges' may protrude to shallow depths along faults originating in the basement. The basement horsts appear to be overpressured relative to the intervening grabens. The principal thesis of this paper is that the two main driving forces of fluid flow in the basin are gravitation, due to elevation differences of the topographic relief, and tectonic compression. The flow field is unconfined in the gravitational regime, whereas it is confined in the compressional regime. The nature and geometry of the fluid potential field between the two regimes are controlled by the sedimentary and structural features of the rock units in that domain, characterized by highly permeable and localized sedimentary windows, conductive faults and fracture zones. The transition between the two potential fields can be gradual or abrupt in the vertical, and island-like or ridge-like in plan view. The depth of the boundary zone can vary between 400 and 2000 m. Recharge to the gravitational regime is inferred to occur from infiltrating precipitation water, whereas that to the confined regime is from pore volume reduction due to the basement's tectonic compression. [source] Honour and duty at sea, 1660,1815HISTORICAL RESEARCH, Issue 190 2002N. A. M. Rodger This article looks at the changing meaning of the concepts of honour and duty among sea officers over the ,long eighteenth century'. As gentlemen and as fighting men, sea officers felt particularly close to the concept of honour; but as members of a skilled, semi,bourgeois profession which was substantially open to talent, they were seen by others as being on the margins of gentility. The rise of the middle,class virtues of duty and service in public esteem at the end of the century, benefited the sea officers by making their long,standing combination of honour and duty fashionable. [source] Comparison of quality and shelf life of buffalo meat patties stored at refrigeration temperatureINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 11 2009Gurunathan Kandeepan Summary Scientific investigation on the quality changes of processed meat products will boost and sustain the meat production and utilization in buffalo abundant countries. A programme was undertaken to compare the quality of buffalo meat patties made from intensively reared young male, semi extensively reared spent male and female groups and stored at refrigeration temperature (4 ± 1 °C). Buffalo meat patties were evaluated for shelf life attributes by analysing the changes in physicochemical, microbiological and sensory attributes. The overall acceptability of patties was better in spent buffalo group than young male group. Increasing storage time resulted in significantly higher pH, TBARS, total aerobic mesophils, coliforms, Staphylococcus aureus and psychrophilic counts but decreased appearance, flavour, juiciness, tenderness, connective tissue residue and overall acceptability scores of buffalo meat patties. The patties were well acceptable within 20 days in young male group and 25 days in spent buffalo group respectively during refrigerator storage. [source] Reintegration Support for Young Ex-Combatants: A Right or a Privilege?INTERNATIONAL MIGRATION, Issue 5 2007Krijn Peters ABSTRACT Under-age and youthful combatants are the major participants in contemporary African conflicts and, therefore, the largest group to be disarmed, demobilized and reintegrated when peace agreements are signed. Programmes to support this process, so-called disarmament, demobilization and reintegration (DDR) programmes, usually have two main objectives: 1) to reduce security risks; and 2) make ex-combatants less dependent upon their home communities once returned. However, badly designed or implemented DDR programmes can jeopardize a country's fragile peace and rehabilitation process. This article uses the Sierra Leone case to explore the efficacy of DDR programmes. It questions whether the reintegration options offered to the demobilized ex-combatants were appropriate to the context. In a country where more than 70 per cent of the population depends on (semi-)subsistence agriculture, the most popular reintegration package among the young ex-combatants was vocational training - only 15 per cent of the ex-combatants chose the "agricultural package". The article questions whether young ex-combatants are simply disinterested in farming, and, if so, whether vocational skills training programmes offer realistic alternative livelihood opportunities. This article argues that most ex-combatants have not been able to achieve sustainable livelihoods skills due to failures in DDR programmes. The existence of a large reservoir of marginalized, foot-loose youth has been widely acknowledged as one of the root causes of the conflict in Sierra Leone. There is clear evidence that one result of the poor DDR design and implementation is that this reservoir has not been sufficiently drained in Sierra Leone. Les principaux participants aux conflits contemporains en Afrique sont de jeunes combattants, parfois mineurs, qui représentent donc le plus important groupe à désarmer, à démobiliser et à réintégrer une fois les accords de paix signés. Les programmes d'appui à ce processus, appelés programmes DDR (désarmement, démobilisation et réintégration), comportent généralement deux objectifs principaux : 1) la réduction des risques liés à la sécurité; et 2) la diminution de la dépendance des ex-combattants à l'égard de leur communauté d'origine lorsqu'ils y retournent. Cependant, des programmes DDR mal conçus ou mal appliqués peuvent mettre en danger le processus fragile de paix et de redressement du pays. L'auteur prend le cas de la Sierra Leone pour vérifier l'efficacité de ces programmes. Il pose la question de l'adéquation au contexte ambiant des options de réintégration offertes aux ex-combattants démobilisés. Dans un pays où plus de 70 % de la population dépendent d'une agriculture de (semi-)subsistance, la formule de réintégration qui a rencontré le plus de succès parmi les jeunes ex-combattants était celle de la formation professionnelle. Seuls 15 % des ex-combattants ont choisi le programme agricole. L'auteur de l'article se demande si les jeunes ex-combattants ont simplement perdu tout intérêt pour l'agriculture, et, dans ce cas, si les programmes de formation professionnelle offrent des possibilités réalistes d'accéder à d'autres moyens d'existence. Dans cet article, il seramontré que les carences dans les programmes DDR n'ont pas permis à la plupart des ex-combattants d'acquérir les qualifications voulues pour s'assurer des moyens d'existence durables. Or, il faut savoir que l'origine du conflit en Sierra Leone est en grande partie attribuée à la présence massive de jeunes gens marginalisés et sans attaches. De toute évidence, ces programmes, tels qu'ils ont été conçus et mis en ,uvre, n'ont pas suffisamment résorbé cette présence massive. Los combatientes jóvenes menores de edad son los principales participantes en los conflictos africanos contemporáneos y, en consecuencia, el grupo más grande que es desarmado, desmovilizado y reintegrado cuando se firman acuerdos de paz. Los programas en apoyo de este proceso, denominados programas de desarme, desmovilización y reintegración (DDR), suelen tener dos objetivos principales: 1) reducir los riesgos de seguridad; y 2) reducir la dependencia de los excombatientes en sus comunidades de origen tras su retorno. Sin embargo, si los programas DDR no están bien diseñados o no se aplican eficazmente, pueden poner en peligro el frágil proceso de paz y rehabilitación de un país. En el presente artículo se pone como ejemplo el caso de Sierra Leona para analizar la eficacia de los programas DDR. Se cuestiona si las opciones de reintegración ofrecidas a los excombatientes desmovilizados fueron apropiadas para el contexto. En un país donde más del 70 por ciento de la población depende de la agricultura de (semi)subsistencia, el conjunto más popular de medidas de reintegración entre los jóvenes excombatientes era la formación profesional -sólo el 15 por ciento de los excombatientes eligió el "conjunto de medidas agrícolas". En el artículo se pregunta si los jóvenes ex combatientes sencillamente no tienen interés en la agricultura y, en ese caso, si los programas de formación vocacional ofrecen otras oportunidades de subsistencia realistas. En este artículo se sostiene que la mayoría de los excombatientes no han podido adquirir una especialización sostenible que les permita sobrevivir debido a las deficiencias de los programas DDR. Se reconoce, en general, que la existencia de una gran reserva de jóvenes marginados y errantes es una de las causas básicas del conflicto en Sierra Leona. Hay pruebas evidentes de que una de las consecuencias del deficiente diseño y ejecución de los programas DDR es el insuficiente aprovechamiento de esta gran reserva en Sierra Leona. [source] A comparison of sexual satisfaction and post-natal depression in the UK and TaiwanINTERNATIONAL NURSING REVIEW, Issue 3 2006Y.C. Huang mmedsci Aim:, To compare the sexual expression and sexual satisfaction of women in the UK and Taiwan before and after childbirth, to determine if there is an association between self reported sexual satisfaction and postnatal depression (PND) and the main sources of sexual information for women during this period. Method:, A comparative survey of postnatal women in the UK and Taiwan using a selfadministered questionnaire, a semi structured interview and the Edinburgh Postnatal Depression Scale (EPDS) to investigate sexual satisfaction, sexual expression and main sources of information as well the prevalence of postnatal depression. Results:, Seventy per cent of the UK women and 89% of the Taiwanese women were generally satisfied with their sex life during the postnatal period although in both countries women thought that sexual expression was not as important to themselves as to their partner. There were differences in ranking criteria for physical and emotional sexual satisfaction in the two countries. Eighty-three per cent of UK women had sufficient information about sex during the postnatal period compared to 60% of Taiwanese women. There was no significant difference in the prevalence of PND (18% UK, 19% Taiwan p < 0.01 ANOVA) but significant negative associations (correlation coefficient) between ,sexual self-confidence' and PND in the UK (p < 0.01) and Taiwan (p < 0.05). UK Women with an unsatisfactory sex life (p < 0.05), insufficient sexual information (p < 0.05) and sexual worries after birth (p < 0.05) were more likely to have symptoms of PND. There was a strong association between a poor relationship with her partner and PND (p < 0.001). Conclusions:, These associations may be either a consequence of or a contributing factor to PND. The observed differences between the two countries may be attributed to cross cultural factors and differences in health care systems although further investigation is required. [source] Mixture modelling of medical magnetic resonance dataJOURNAL OF CHEMOMETRICS, Issue 6 2002Ron Wehrens Abstract In clinical decision making, (semi-)automatic unsupervised classification of data for diagnostic purposes is becoming more and more important. This paper describes the application of mixture modelling, a clustering where multivariate Gaussians are used to describe clusters in the data, to in vivo nuclear magnetic resonance data of patients with brain tumours. Images as well as localized spectra are analysed. The method is able to automatically generate meaningful classifications. Moreover, the results of clustering both the image and spectral data are in close agreement. Copyright © 2002 John Wiley & Sons, Ltd. [source] Older people and falls: health status, quality of life, lifestyle, care networks, prevention and views on service use following a recent fallJOURNAL OF CLINICAL NURSING, Issue 16 2009Brenda Roe Aim and objective., This study has investigated older people's experiences of a recent fall, its impact on their health, lifestyle, quality of life, care networks, prevention and their views on service use. Background., Falls are common in older people and prevalence increases with age. Falls prevention is a major policy and service initiative. Design., An exploratory, qualitative design involving two time points. Method., A convenience sample of 27 older people from two primary care trusts who had a recent fall. Taped semi structured qualitative interviews were conducted and repeated at follow up to detect change over time and repeat falls. Data were collected on their experience of falls, health, activities of living, lifestyle, quality of life, use of services, prevention of falls, informal care and social networks. Content analysis of transcribed interviews identified key themes. Results., The majority of people fell indoors (n = 23), were repeat fallers (n = 22) with more than half alone when they fell (n = 15). For five people it was their first ever fall. Participants in primary care trust 1 had a higher mean age than those in primary care trust 2 and had more injurious falls (n = 12, mean age 87 years vs. n = 15, mean age 81 years). The majority of non-injurious falls went unreported to formal services. Falls can result in a decline in health status, ability to undertake activities of living, lifestyle and quality of life. Conclusions., Local informal care and support networks are as important as formal care for older people at risk of falls or who have fallen. Access to falls prevention programmes and services is limited for people living in more rural communities. Relevance to practice., Falls prevention initiatives and services should work with local communities, agencies and informal carers to ensure equitable access and provision of information, resources and care to meet the needs of older people at risk or who have fallen. [source] Notes on the distribution and abundance of the caecilian Boulengerula uluguruensis (Amphibia: Gymnophiona: Caeciliidae) in the Uluguru Mountains, TanzaniaAFRICAN JOURNAL OF ECOLOGY, Issue 1 2006G. John Measey Abstract Boulengerula uluguruensis is a terrestrial caeciliid caecilian described from the Uluguru Mountains of Tanzania. We investigated the relative abundance of B. uluguruensis in agricultural and forested habitats at the beginning of the rainy season. This caecilian was found over a wide altitudinal range (450,1175 m a.s.l.), and in many land cover types (including natural forest, plantation forest and small scale agriculture), and different soil textures (including very compact soil). Based on quantitative and semi-quantitative surveys, B. uluguruensis is more abundant than any other subterranean lower vertebrate in this area, with densities up to 0.4 individuals m,2 in some agricultural plots. The hypothesis proposed, that B. uluguruensis is more abundant in agriculture than their native forest, could not be conclusively tested during this brief visit, although the data that were collected do not indicate to the contrary. Likewise, the size of animals from forest and agricultural populations could not be objectively compared. Résumé Boulengerulauluguruensis est un caecilian caeciliid terrestre décrit des montagnes d'Ulguru en Tanzanie. Nous avons relevé l'abondance relative du B. uluguruensis dans des habitats agricoles et boisés au début de la saison des pluies. Ce caecilian fut trouvé dans une grande envergure d'altitude (450 to 1175 m asl), et dans plusieurs genres de couverture des terres (y compris forêt naturelle, plantation, et agriculture à petite échelle), et differenté textures du sol (y compris sol de forte densité). Basé sur des enquêtes quantitatives et semi- quantitatives, le B. uluguruensis fut plus abondant que toute autre vertébré souterrain dans cette région, avec une densité jusqu'à 0,4 individus par m2 dans quelques terrains agricoles. Notre visite fut trop brève pour que nous puissions vérifier l'hypothèse avancée que B.uluguruensis est plus abondant dans l'agriculture que dans la forêt native dont ils sont indigènes, bien que les données accumulées ne montrent pas le contraire. De la même manière, la taille des animaux provenant des populations forestières et agricoles n'a pas pu être comparé objectivement. [source] Linking physiological traits to impacts on community structure and function: the role of root hemiparasitic Orobanchaceae (ex-Scrophulariaceae)JOURNAL OF ECOLOGY, Issue 1 2005G. K. PHOENIX Summary 1The hemiparasitic Orobanchaceae (ex-Scrophulariaceae) are characterized by a distinctive suite of ecophysiological traits. These traits have important impacts on host plants and non-host plants, and influence interactions with other trophic levels. Ultimately, they can affect community structure and functioning. Here, we review these physiological traits and discuss their ecological consequences. 2The root hemiparasitic Orobanchaceae form a convenient subset of the parasitic angiosperms for study because: they are the most numerous and most widely distributed group of parasitic angiosperms; their physiological characteristics have been well studied; they are important in both agricultural and (semi)natural communities; and they are tractable as experimental organisms. 3Key traits include: high transpiration rates; competition with the host for nutrients and haustorial metabolism of host-derived solutes; uptake of host-derived secondary metabolites; dual autotrophic and heterotrophic carbon nutrition; distinct carbohydrate biochemistry; high nutrient concentrations in green leaf tissue and leaf litter; and small (often hairless and non-mycorrhizal) roots. 4Impacts on the host are detrimental, which can alter competitive balances between hosts and non-hosts and thus result in community change. Further impacts may result from effects on the abiotic environment, including soil water status, nutrient cycling and leaf/canopy temperatures. 5However, for non-host species and for organisms that interact with these (e.g. herbivores and pollinators) or for those that benefit from changes in the abiotic environment, the parasites may have an overall positive effect, suggesting that at the community level, hemiparasites may also be considered as mutualists. 6It is clear that through their distinctive suite of physiological traits hemiparasitic Orobanchaceae, have considerable impacts on community structure and function, can have both competitive and positive interactions with other plants, and can impact on other trophic levels. Many community level effects of parasitic plants can be considered analogous to those of other parasites, predators or herbivores. [source] Synthesis and reactions of 4-benzoyl-1,5-diaryl-1H -pyrazole-3-carbonyl chlorides with various semi- and thiosemicarbazidesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2010Elif Korkusuz The 1H -pyrazole-3-carboxylic acids 2 were converted via reactions of their acid chlorides 3 with some semi- and thiosemicarbazide derivatives into the corresponding new phenylsemi- and thiosemicarbazides 4a,e, 6, 5-(pyrazol-3-yl)-4H -1,2,4-triazol-3-thiones 5a,b, and 2-(pyrazol-3-yl)-1,3,4-thiadiazol 7 derivatives, in good yields (45-97%, respectively). The reactions of 4a,c,e with Lawesson reagent lead to the products 6 and 7 formation. The structures of these newly synthesized compounds were determined from the IR, 1H- and 13C-NMR spectroscopic data and elemental analyses. J. Heterocyclic Chem., (2010). [source] Probing the limits of molecular imprinting: strategies with a template of limited size and functionalityJOURNAL OF MOLECULAR RECOGNITION, Issue 1 2009Miruna Petcu Abstract A series of polymers molecularly imprinted with the general anaesthetic propofol were synthesized using both semi- and non-covalent approaches. The polymers were evaluated with respect to template rebinding in both aqueous and organic media. In aqueous media, the observed propofol binding in these polymer systems was largely hydrophobic and non-specific in nature. In non-polar solvents such as hexane, electrostatic (hydrogen bonding) interactions dominate resulting in some selectivity. The implication of these results, in conjunction with those obtained using structures of similar size in other studies, is that propofol, a template possessing limited functionality and size, appears to define the lower limit for template size and degree of functionalization that can be used for the creation of ligand-selective recognition sites in molecularly imprinted polymers. Furthermore, studies with alternative ligands indicate that the steric crowding of a ligand's functionality to the polymer contributes to the extent of polymer,ligand recognition. Copyright © 2008 John Wiley & Sons, Ltd. [source] Plant functional group composition and large-scale species richness in European agricultural landscapesJOURNAL OF VEGETATION SCIENCE, Issue 1 2008Jaan Liira Abstract Question: Which are the plant functional groups responding most clearly to agricultural disturbances? Which are the relative roles of habitat availability, landscape configuration and agricultural land use intensity in affecting the functional composition and diversity of vascular plants in agricultural landscapes? Location: 25 agricultural landscape areas in seven European countries. Methods: We examined the plant species richness and abundance in 4 km × 4 km landscape study sites. The plant functional group classification was derived from the BIOLFLOR database. Factorial decomposition of functional groups was applied. Results: Natural habitat availability and low land use intensity supported the abundance and richness of perennials, sedges, pteridophytes and high nature quality indicator species. The abundance of clonal species, C and S strategists was also correlated with habitat area. An increasing density of field edges explained a decrease in richness of high nature quality species and an increase in richness of annual graminoids. Intensive agriculture enhanced the richness of annuals and low nature quality species. Conclusions: Habitat patch availability and habitat quality are the main drivers of functional group composition and plant species richness in European agricultural landscapes. Linear elements do not compensate for the loss of habitats, as they mostly support disturbance tolerant generalist species. In order to conserve vascular plant species diversity in agricultural landscapes, the protection and enlargement of existing patches of (semi-) natural habitats appears to be more effective than relying on the rescue effect of linear elements. This should be done in combination with appropriate agricultural management techniques to limit the effect of agrochemicals to the fields. [source] Monitoring of Emulsion Polymerisation Processes using Ion Mobility Spectrometry,A Pilot StudyMACROMOLECULAR REACTION ENGINEERING, Issue 2-3 2009Wolfgang Vautz Abstract Online monitoring of monomer concentrations in (semi-) batch emulsion polymerisation reactors is important for safe and cost-efficient operation of production plants. In the present pilot study, ion mobility spectrometry was applied for monitoring the concentration during emulsion polymerisation of vinyl acetate (VA) using UV light for ionisation of the headspace of a continuous sample flow. Satisfactory sensitivity for online process monitoring of the monomer concentration in the reactor was observed (LOD 400 ng,·,L,1 air, equivalent to <1%). Furthermore, it is possible to discriminate between VA and other common monomers [butyl acrylate (BA), methyl methacrylate (MMA)]. Using the more efficient , -radiation ionisation, monomer concentration could be measured even in the final latex as a measure of the final product properties. [source] Measurable selectors for the metric projectionMATHEMATISCHE NACHRICHTEN, Issue 1 2003B. Cascales Abstract Let Y and Z be two topological spaces and F : Y × Z , , a function that is upper semi,continuous in the first variable and lower semi,continuous in the second variable. If Z is Polish and for every y , Y there is a point z , Z with F(y, z) = infw,ZF(y, w) we prove that there is a nice measurable function h : Y , Z satisfying F(y, h(y)) = infz,ZF(y, z) for every y , Y . As an application we obtain the existence of universally measurable selectors for the metric projection onto weakly K,analytic convex proximinal subsets of a Banach space, which then allows us to prove that Lp(,, Y ) is proximinal in Lp(,, X) for every proximinal weakly K,analytic subspace Y of a Banach space X. [source] Genetic structure of Euclea schimperi (Ebenaceae) populations in monsoonal fog oases of the southern Arabian PeninsulaNORDIC JOURNAL OF BOTANY, Issue 3-4 2007Jörg Meister Euclea schimperi, a widespread Afromontane shrub or tree, occurs in the Arabian Peninsula in fragmented, semi-evergreen or evergreen woodland refugia in wet escarpment localities of the western and southern mountain chains. In the southern coastal mountains, the (semi-) evergreen woodland with E. schimperi is close to its ecological limit and consequently today very rare, with the exception of the monsoonal fog oases of east Yemen and south Oman in the central south coast of the Arabian Peninsula. Due to the steep precipitation gradient from the centre to the western edge in this monsoon affected area, E. schimperi is found in two different habitat types: in continuous woodland belts in the Hawf and Dhofar mountains, and in isolated, scattered woodland patches in the Fartak Mountains. Ten populations (138 individuals) from across the southern Arabian distribution area of the species were analysed using chloroplast microsatellites and AFLP fingerprinting to a) reconstruct the phylogeographical pattern of E. schimperi on the southern Arabian Peninsula and b) to evaluate the consequences of population fragmentation on the genetic diversity harboured in isolated patches vs cohering stands. Phylogeographical reconstructions show that the distribution area of E. schimperi in the southern Arabian Peninsula is characterised by a geographical split that separates the southwestern populations (representated by material from Jabal Eraf and Jabal Uthmar), from the southcentral populations, which themselves are split from each other into a western (Ras Fartak) and an eastern refugium (Hawf/Dhofar). The analysis of the within-population genetic diversity in E. schimperi populations resulted in a slightly, but not significantly higher genetic variation in small and isolated woodland patches (HS=0.302) compared to larger, cohering stands (HS=0.291). [source] Orthogonal similarity transformation into block-semiseparable matrices of semiseparability rank kNUMERICAL LINEAR ALGEBRA WITH APPLICATIONS, Issue 10 2005M. Van Barel Abstract Very recently, an algorithm, which reduces any symmetric matrix into a semiseparable one of semi- separability rank 1 by similar orthogonality transformations, has been proposed by Vandebril, Van Barel and Mastronardi. Partial execution of this algorithm computes a semiseparable matrix whose eigenvalues are the Ritz-values obtained by the Lanczos' process applied to the original matrix. Also a kind of nested subspace iteration is performed at each step. In this paper, we generalize the above results and propose an algorithm to reduce any symmetric matrix into a similar block-semiseparable one of semiseparability rank k, with k , ,, by orthogonal similarity transformations. Also in this case partial execution of the algorithm computes a block-semiseparable matrix whose eigenvalues are the Ritz-values obtained by the block-Lanczos' process with k starting vectors, applied to the original matrix. Subspace iteration is performed at each step as well. Copyright © 2005 John Wiley & Sons, Ltd. [source] On the synthesis of time-varying LQG weights and noises along optimal control and state trajectoriesOPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 3 2006L. G. Van Willigenburg Abstract A general approach to control non-linear uncertain systems is to apply a pre-computed nominal optimal control, and use a pre-computed LQG compensator to generate control corrections from the on-line measured data. If the non-linear model, on which the optimal control and LQG compensator design is based, is of sufficient quality, and when the LQG compensator is designed appropriately, the closed-loop control system is approximately optimal. This paper contributes to the selection and computation of the time-varying LQG weighting and noise matrices, which determine the LQG compensator design. It is argued that the noise matrices may be taken time-invariant and diagonal. Three very important considerations concerning the selection of the time-varying LQG weighting matrices are turned into a concrete computational scheme. Thereby, the selection of the time-varying LQG weighting matrices is reduced to selecting three scalar design parameters, each one weighting one consideration. Although the three considerations seem straightforward they may oppose one another. Furthermore, they usually result in time-varying weighting matrices that are indefinite, rather than positive (semi) definite as required for the LQG design. The computational scheme presented in this paper addresses and resolves both problems. By two numerical examples the benefits of our optimal closed-loop control system design are demonstrated and evaluated using Monte Carlo simulation. Copyright © 2005 John Wiley & Sons, Ltd. [source] An elastodynamic Galerkin Boundary Element Formulation for semi-infinite domains in time-domainPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2008Lars Kielhorn The present work focuses on the problem of modelling wave propagation phenomena within a 3,d elastodynamic halfspace by use of a symmetric Galerkin Boundary Element formulation. Unfortunately, this formulation requires the evaluation of hypersingular integral kernels which are regularized by integration by parts. In Boundary Element Methods semi,infinite domains are commonly approximated in space by considering just a sufficiently large enough region. Applying this simple discretization to the symmetric formulation implies the evaluation of the hypersingular bilinear form on a truncated mesh which will fail due to the regularization approach. To overcome this drawback a methodology based on infinite elements is presented. The numerical tests show that this approach is promising for treating semi,infinite domains with a symmetric Galerkin scheme. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Small firm networks: a successful approach to innovation?R & D MANAGEMENT, Issue 3 2002Victoria Hanna This paper considers the increasing trend of inter,working among small firms. Networks of small firms co,operate in certain activities, such as marketing, purchasing, R&D, training or manufacturing. But does co,operation lead to innovation? To answer this question published evaluations of small firms co,operating for mutual benefit are reappraised. Inter,working among small firms is then investigated further by interviewing three network brokers. The brokers were funded by regional governments and they facilitated co,operation between small firms. These semi,structured discussions explored the key characteristics of successful networks, the responsibilities of the broker and the level of innovation occurring. Networking is primarily a competitive response. It needs to evolve into a mechanism to enable small firms to develop innovative products and processes jointly. Small firms may have to rethink their approach to co,operation, and their motives for initiating inter,working if they are to benefit fully from co,operation. [source] | |||||||||||||||||||||||||||||||||||||||||||