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Kinds of One Part Selected AbstractsElectrochemically Induced Modulation of the Catalytic Activity of a Reversible Redoxsensitive RiboswitchELECTROANALYSIS, Issue 9 2008Denise Strohbach Abstract Over the past decade, RNA conformation has been shown to respond to external stimuli. Thus, dependent on the presence of a high affinity ligand, specifically designed ribozymes can be regulated in a classical allosteric way. In this scenario, a binding event in one part of the RNA structure induces conformational changes in a separated part, which constitutes the catalytic centre. As a result activity is switched on (positive regulation) or off (negative regulation). We have developed a hairpin aptazyme responding to flavine mononucleotide (FMN). Ribozyme activity is dependent on binding of FMN and thus is switched on in the presence of FMN in its oxidized form. Under reducing conditions, however, FMN changes its molecular geometry, which is associated with loss of binding and consequently down-regulation of ribozyme activity. While in previous experiments sodium dithionite was used for reduction of FMN, we now present an assay for electrochemically induced activity switching. We have developed an electrochemical microcell that allows for iterative cycles of reduction/oxidation of FMN in an oxygen free atmosphere and thus for reversible switching of ribozyme activity. The reaction proceeds in droplets of 3 to 10,,L at micro- to nanomolar concentrations of the reaction components. [source] Comparing in-work benefits and the reward to work for families with children in the US and the UKFISCAL STUDIES, Issue 1 2001Mike Brewer Abstract The income transfer systems for low-income families in the US and the UK try both to reduce poverty and to encourage work. In-work benefits are a key part of both countries' strategies through the earned income tax credit and the working families' tax credit (and predecessors) respectively. But tax credits are only one part of the whole tax and welfare system. In-work benefits, taxes and welfare benefits combine in both countries to provide good financial incentives for lone parents to do minimum-wage work, but poorer incentives to increase earnings further. But direct comparisons of budget constraints hide important points of detail. First, not enough is known about what determines take-up of in-work benefits. Second, the considerable differences in assessment and payment mechanisms and frequency between EITC and WFTC mean that low-income families in the US and the UK may respond very differently to apparently similar financial incentives. [source] Signals of range expansions and contractions of vascular plants in the high Alps: observations (1994,2004) at the GLORIA, master site Schrankogel, Tyrol, AustriaGLOBAL CHANGE BIOLOGY, Issue 1 2007HARALD PAULI Abstract High mountain ecosystems are defined by low temperatures and are therefore considered to react sensitively to climate warming. Responding to observed changes in plant species richness on high peaks of the European Alps, an extensive setup of 1 m × 1 m permanent plots was established at the alpine-nival ecotone (between 2900 and 3450 m) on Mount Schrankogel, a GLORIA master site in the central Tyrolean Alps, Austria, in 1994. Recording was repeated in a representative selection of 362 quadrats in 2004. Ten years after the first recording, we observed an average change in vascular plant species richness from 11.4 to 12.7 species per plot, an increase of 11.8% (or of at least 10.6% at a 95% confidence level). The increase in species richness involved 23 species (about 43% of all taxa found at the ecotone), comprising both alpine and nival species and was pronouncedly higher in plots with subnival/nival vegetation than in plots with alpine grassland vegetation. Only three species showed a decrease in plot occupancy: one was an annual species, one was rare, and one a common nival plant that decreased in one part of the area but increased in the uppermost part. Species cover changed in relation to altitudinal preferences of species, showing significant declines of all subnival to nival plants, whereas alpine pioneer species increased in cover. Recent climate warming in the Alps, which has been twice as high as the global average, is considered to be the primary driver of the observed differential changes in species cover. Our results indicate an ongoing range contraction of subnival to nival species at their rear (i.e. lower) edge and a concurrent expansion of alpine pioneer species at their leading edge. Although this was expected from predictive distribution models and different temperature-related habitat preferences of alpine and nival species, we provide first evidence on , most likely , warming-induced species declines in the high European Alps. The projected acceleration of climate warming raises concerns that this phenomenon could become the major threat to biodiversity in high mountains. [source] A quantitative identification technique for a two-dimensional subsurface defect based on surface temperature measurementHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 4 2009Chunli Fan Abstract The inverse identification of a subsurface defect boundary is an important part of an inverse heat conduction problem, and is also the basis for the quantitative development of a nondestructive thermographic inspection technique. For the commonly encountered quantitative thermographic defect identification problem when the test piece is heated from one part of the outer boundary, our previous study showed that some parts of the defect boundary are sensitive to the initial defect boundary prediction of the conjugate gradient method. In this paper, the heat transfer mechanism inside a test piece with this problem is analyzed by building a two-dimensional model. A new method, the multiple measurements combination method (MMCM), is also presented which combines the identification algorithm study with the optimization of the thermographic detection technique to solve the problem. Numerical experiments certified the effectiveness of the present method. The temperature measurement error and the initial prediction of the defect boundary shape have little effect on the identification result. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20251 [source] A distributed approach for estimating catchment evapotranspiration: comparison of the combination equation and the complementary relationship approachesHYDROLOGICAL PROCESSES, Issue 8 2003Z. X. Xu Abstract In large river basins, there may be considerable variations in both climate and land use across the region. The evapotranspiration that occurs over a basin may be drastically different from one part of the region to another. The potential influence of these variations in evapotranspiration estimated for the catchment is weakened by using a spatially based distributed hydrological model in such a study. Areal evapotranspiration is estimated by means of approaches requiring only meteorological data: the combination equation (CE) model and the complementary relationship approach,the complementary relationship areal evapotranspiration (CRAE) and advection,aridity (AA) models. The capability of three models to estimate the evapotranspiration of catchments with complex topography and land-use classification is investigated, and the models are applied to two catchments with different characteristics and scales for several representative years. Daily, monthly, and annual evapotranspiration are estimated with different accuracy. The result shows that the modified CE model may underestimate the evapotranspiration in some cases. The CRAE and AA models seem to be two kinds of effective alternatives for estimating catchment evapotranspiration. Copyright © 2003 John Wiley & Sons, Ltd. [source] Orthopaedic patients' experience of motor vehicle accident in SingaporeINTERNATIONAL NURSING REVIEW, Issue 1 2008K.L. Tan mn (ortho nrsg) Aim:, The purpose of this paper is to present a study that explored the experiences of orthopaedic patients injured in motor vehicle accidents (MVAs), from the time of the accident until 6 months after being discharged from hospital. Background:, Trauma injuries from MVAs are increasing, with the number of deaths from such injuries continuing to rise. Victims often sustain open fractures to more than one part of their body and need rehabilitation and support to adjust to long-term chronic or permanent disability. In the last decade, research pertaining to trauma nursing has concentrated on neurologically injured patients. Although there is a paucity of research on the nursing perspective of psychological care for non-neurologically injured patients, the majority of studies located were mainly quantitative in nature and did not analyse the personal experiences of orthopaedic patients. Method:, A qualitative naturalistic inquiry approach was used, which provided a first-hand account of the traumatic MVA event experienced by six orthopaedic participants in Singapore. Data were collected from face-to-face in-depth interviews. Participants were voluntarily recruited through purposeful sampling and ,snowballing'. Interviews were audiotaped and transcribed verbatim in preparation for analysis. Findings:, The analysis of information explicated four main themes: the experience of the event, the effect of hospitalization, surviving the event and self-transformation. Conclusion:, The study provided an understanding of orthopaedic patients' experience of MVA in Singapore. The findings of the study have the potential to contribute to the limited qualitative research available concerning victims' experiences of MVAs and nurses caring for MVA victims. [source] Becoming A Leader In A Complex OrganizationJOURNAL OF MANAGEMENT STUDIES, Issue 8 2000Jean-Louis Denis For a new leader, the process of entering and establishing a position of leadership in a complex organization presents a major challenge. This challenge seems particularly acute when authority, goals and technology are ambiguous, as in many professional service organizations. In this paper, we integrate ideas from the literature on socialization and role theory as well as that on executive succession processes to view new leader integration as a mutual adjustment process between two trajectories , that of the organization and that of the new leader. It is argued that this may lead to four possible types of integration outcomes: assimilation, transformation, accommodation and parallelism. Drawing on a case study of a large hospital, the paper identifies several mechanisms that can be mobilized by the new leader to enhance his or her room for man,uvre as the integration process evolves. The mechanisms can be classified as collaborative or affirmative, with each type having different risks and advantages. The case analysis further reveals that leader integration processes may be differentiated between different activity domains, dynamic over time (as the use of one type of integration approach alters the potential for another later), and interactive across different activity domains (as events in one part of the organization have consequences for those occurring in another). [source] Developing organizational learning in the NHSMEDICAL EDUCATION, Issue 1 2001Sandra M Nutley Learning has been identified as a central concern for a modernized NHS. Continuing professional development has an important role to play in improving learning but there is also a need to pay more attention to collective (organizational) learning. Such learning is concerned with the way organizations build and organize knowledge. Recent emphasis within the NHS has been on the codification of individual and collective knowledge , for example, guidelines and National Service Frameworks. This needs to be balanced by more personalized knowledge management strategies, especially when dealing with innovative services that rely on tacit knowledge to solve problems. Having robust systems for storing and communicating knowledge is only one part of the challenge. It is also important to consider how such knowledge gets used, and how routines become established within organizations that structure the way in which knowledge is deployed. In many organizations these routines favour the adaptive use of knowledge, which helps organizations to achieve incremental improvements to existing practices. However, the development of organizational learning in the NHS needs to move beyond adaptive (single loop) learning, to foster skills in generative (double loop) learning and meta-learning. Such learning leads to a redefinition of the organization's goals, norms, policies, procedures or even structures. This paper argues that moving the NHS in this direction will require attention to the cultural values and structural mechanisms that facilitate organizational learning. [source] Unified finite element discretizations of coupled Darcy,Stokes flowNUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 2 2009Trygve Karper Abstract In this article, we discuss some new finite element methods for flows which are governed by the linear stationary Stokes system on one part of the domain and by a second order elliptic equation derived from Darcy's law in the rest of the domain, and where the solutions in the two domains are coupled by proper interface conditions. All the methods proposed here utilize the same finite element spaces on the entire domain. In particular, we show how the coupled problem can be solved by using standard Stokes elements like the MINI element or the Taylor,Hood element in the entire domain. Furthermore, for all the methods the handling of the interface conditions are straightforward. © 2008 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2009 [source] Quercitol and osmotic adaptation of field-grown Eucalyptus under seasonal drought stressPLANT CELL & ENVIRONMENT, Issue 7 2008STEFAN K. ARNDT ABSTRACT This study investigated the role of quercitol in osmotic adjustment in field-grown Eucalyptus astringens Maiden subject to seasonal drought stress over the course of 1 year. The trees grew in a native woodland and a farm plantation in the semi-arid wheatbelt region of south Western Australia. Plantation trees allocated relatively more biomass to leaves than woodland trees, but they suffered greater drought stress over summer, as indicated by lower water potentials, CO2 assimilation rates and stomatal conductances. In contrast, woodland trees had relatively fewer leaves and suffered less drought stress. Plantation trees under drought stress engaged in osmotic adjustment, but woodland trees did not. Quercitol made a significant contribution to osmotic adjustment in drought-stressed trees (25% of total solutes), and substantially more quercitol was measured in the leaves of plantation trees (5% dry matter) than in the leaves of woodland trees (2% dry matter). We found no evidence that quercitol was used as a carbon storage compound while starch reserves were depleted under drought stress. Differences in stomatal conductance, biomass allocation and quercitol production clearly indicate that E. astringens is both morphologically and physiologically ,plastic' in response to growth environment, and that osmotic adjustment is only one part of a complex strategy employed by this species to tolerate drought. [source] Genetic and environmental contributions to variation in baboon cranial morphologyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Charles C. Roseman Abstract The development, function, and integration of morphological characteristics are all hypothesized to influence the utility of traits for phylogenetic reconstruction by affecting the way in which morphological characteristics evolve. We use a baboon model to test the hypotheses about phenotypic and quantitative genetic variation of traits in the cranium that bear on a phenotype's propensity to evolve. We test the hypotheses that: 1) individual traits in different functionally and developmentally defined regions of the cranium are differentially environmentally, genetically, and phenotypically variable; 2) genetic covariance with other traits constrains traits in one region of the cranium more than those in others; 3) and regions of the cranium subject to different levels of mechanical strain differ in the magnitude of variation in individual traits. We find that the levels of environmental and genetic variation in individual traits are randomly distributed across regions of the cranium rather than being structured by developmental origin or degree of exposure to strain. Individual traits in the cranial vault tend to be more constrained by covariance with other traits than those in other regions. Traits in regions subject to high degrees of strain during mastication are not any more variable at any level than other traits. If these results are generalizable to other populations, they indicate that there is no reason to suppose that individual traits from any one part of the cranium are intrinsically less useful for reconstructing patterns of evolution than those from any other part. Am J Phys Anthropol 143:1,12, 2010. © 2010 Wiley-Liss, Inc. [source] Random dense bipartite graphs and directed graphs with specified degreesRANDOM STRUCTURES AND ALGORITHMS, Issue 2 2009Catherine Greenhill Abstract Let s and t be vectors of positive integers with the same sum. We study the uniform distribution on the space of simple bipartite graphs with degree sequence s in one part and t in the other; equivalently, binary matrices with row sums s and column sums t. In particular, we find precise formulae for the probabilities that a given bipartite graph is edge-disjoint from, a subgraph of, or an induced subgraph of a random graph in the class. We also give similar formulae for the uniform distribution on the set of simple directed graphs with out-degrees s and in-degrees t. In each case, the graphs or digraphs are required to be sufficiently dense, with the degrees varying within certain limits, and the subgraphs are required to be sufficiently sparse. Previous results were restricted to spaces of sparse graphs. Our theorems are based on an enumeration of bipartite graphs avoiding a given set of edges, proved by multidimensional complex integration. As a sample application, we determine the expected permanent of a random binary matrix with row sums s and column sums t. © 2009 Wiley Periodicals, Inc. Random Struct. Alg., 2009 [source] Commitment to change: Exploring its role in changing physician behavior through continuing educationTHE JOURNAL OF CONTINUING EDUCATION IN THE HEALTH PROFESSIONS, Issue 4 2004Dr. Jacqueline G. Wakefield MD Abstract Statements of commitment to change are advocated both to promote physician change and to assess interventions designed to promote change. Although commitment to change is only one part of a complex process of change, recent progress has established a solid theoretical and research base to support this approach. Studies have demonstrated that it can be used effectively with many different types of educational activities and that statements of "plans to change" practice can predict actual changes. The importance of follow-up as part of the commitment to change model is becoming clearer, although questions remain about the most effective process is accomplishment this and the optimal timing. Further research is needed to establish the effectiveness of the commitment-to-change approach itself, as well as to better understand the functions (and thus the forms) of the different components of the commitment-to-change model. [source] The pitfalls of extrapolation in conservation: movements and habitat use of a threatened toad are different in the boreal forestANIMAL CONSERVATION, Issue 1 2010J. M. Constible Abstract Widely distributed species often vary geographically in their ecology. Thus, results of studies done in one part of their range cannot necessarily be extrapolated readily to populations elsewhere. This problem is particularly important for threatened species whose ecology has been studied in a few disconnected locations. The Canadian toad Bufo (Anaxyrus) hemiophrys occupies a large geographic range in western North America, but most studies of its ecology have been done in the prairies, where the species is considered to be closely associated with aquatic habitats. However, B. hemiophrys also occurs in boreal forest, where it faces threats from logging activities, especially if it uses upland habitats far from ponds and lakes. We radio-tracked 29 toads in the boreal forest of northern Alberta, Canada to determine their patterns of movement and habitat use. Most movements between fixes were <50 m, but toads sometimes made longer movements exceeding 100 m. Over time, however, these short-term movements combined into large-scale directional movements that were highly variable among toads in both tortuosity and timing, but which generally took toads into upland forested habitats. Putative hibernacula also were located in upland sites. However, despite this terrestriality, toads still were associated with wetlands, using them significantly more often than would be expected based on their proportionate areal contribution to the landscape. Nonetheless, use of upland sites and long-distance terrestrial movements differentiate this population of B. hemiophrys from those studied in prairie environments. Conservation plans based on what we know about the species elsewhere therefore would be inappropriate in this region. Management often requires site-specific information, which can be obtained only from natural-history studies of the populations in question. [source] What happens to translocated game birds that ,disappear'?ANIMAL CONSERVATION, Issue 5 2009M. J. Dickens Abstract The ultimate goal of most translocation efforts is to create a self-sustaining wild population of a species deliberately moved from one part of their range to another. As follow-up of a translocation attempt is often difficult, causes for failure are relatively unknown. Dispersal away from the release site is one potential source of failure because it decreases the likelihood of the released population establishing itself post-translocation. In this study, we used chukar Alectoris chukar as a surrogate for translocated game birds in order to conduct a large-scale experimental study. We observed that these desert-adapted birds demonstrate a strong fidelity for specific water sources. We also report the propensity for the translocated individuals to either disperse and return to their original water source site or remain at the release site. During two field seasons, we observed opposing behaviors such that the proportion of individuals returning to the capture site, versus those remaining at the release site, shifted between years. We analyzed this change between the years as well as within the years to assess the potential underlying causes such as translocated distance, differences in rainfall between seasons and water source type. We concluded that homing behavior was strong in this non-migratory bird species and that strength of this homing behavior varied, potentially due to conditions surrounding the limiting resource, water availability. The large-scale, original data presented here may help to explain why some releases result in a successfully established population while other releases result in widely dispersed individuals. [source] Syntheses of esters through poly(styrene sulfonic acid)/poly(vinyl alcohol) membrane reactorASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 1 2010Tadashi Uragami Abstract Cation exchange membranes prepared from poly(styrene sulfonic acid) (PSA) and poly(vinyl alcohol) (PVA) were cross-linked by both glyoxal and gultaraledehyde and cross-linked membranes furthermore were annealed. The ion exchange capacity of the resulting PSA/PVA membranes increased, and the water content and degree of swelling of PSA/PVA membrane decreased with increasing annealing time. The syntheses of esters from alcohol and acetic acid through various PSA/PVA membranes have been carried out in a diaphragm type cell consisting of two detachable parts in which the membrane was set in the middle of the two parts of cell. When an aqueous solution of alcohol and acetic acid on one part of cell and p -chloro benzene (Cl-Bz) on another part were set, esters formed by the catalytic action of PSA/PVA membrane increased on the Cl-Bz phase with time. These results support that the PSA/PVA membrane could perform both the reaction and separation. The formation of esters in this membrane reactor was a secondary reaction as well as general the esterification between alcohols and acids. The catalytic action in the esterification of the PSA/PVA membranes prepared by changing the ratio of PSA/PVA and the amount of casting solution was also investigated. The rate of esterification reaction was significantly dependent on the number of sulfonic acid group in the effective membrane volume. The rate of reaction per mEq SO3H increased with an increase of the degree of swelling of the membrane and decreasing membrane thickness. In the esterifications of methanol, ethanol and n -propanol with acetic acid, the reactivity through the PSA/PVA membrane was higher than that with HCl as catalyst. In that of n -butanol with acetic acid, however, it was vice versa. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Distributed intelligence in an astronomical Distributed Sensor NetworkASTRONOMISCHE NACHRICHTEN, Issue 3 2008R.R. White Abstract The Telescope Alert Operations Network System (TALONS) was designed and developed in the year 2000, around the architectural principles of a distributed sensor network. This network supported the original Rapid Telescopes for Optical Response (RAPTOR) project goals; however, only with further development could TALONS meet the goals of the larger Thinking Telescope Project. The complex objectives of the Thinking Telescope project required a paradigm shift in the software architecture , the centralised intelligence merged into the TALONS network operations could no longer meet all of the new requirements. The intelligence needed to be divorced from the network operations and developed as a series of peripheral intelligent agents, distributing the decision making and analytical processes based on the temporal volatility of the data. This paper is presented as only one part of the poster from the workshop and in it we will explore the details of this architecture and how that merges with the current Thinking Telescope system to meet our project goals. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Facile Oxidation of Leucomethylene Blue and Dihydroflavins by Artemisinins: Relationship with Flavoenzyme Function and Antimalarial Mechanism of ActionCHEMMEDCHEM, Issue 8 2010Richard Abstract The antimalarial drug methylene blue (MB) affects the redox behaviour of parasite flavin-dependent disulfide reductases such as glutathione reductase (GR) that control oxidative stress in the malaria parasite. The reduced flavin adenine dinucleotide cofactor FADH2 initiates reduction to leucomethylene blue (LMB), which is oxidised by oxygen to generate reactive oxygen species (ROS) and MB. MB then acts as a subversive substrate for NADPH normally required to regenerate FADH2 for enzyme function. The synergism between MB and the peroxidic antimalarial artemisinin derivative artesunate suggests that artemisinins have a complementary mode of action. We find that artemisinins are transformed by LMB generated from MB and ascorbic acid (AA) or N -benzyldihydronicotinamide (BNAH) in,situ in aqueous buffer at physiological pH into single electron transfer (SET) rearrangement products or two-electron reduction products, the latter of which dominates with BNAH. Neither AA nor BNAH alone affects the artemisinins. The AA,MB SET reactions are enhanced under aerobic conditions, and the major products obtained here are structurally closely related to one such product already reported to form in an intracellular medium. A ketyl arising via SET with the artemisinin is invoked to explain their formation. Dihydroflavins generated from riboflavin (RF) and FAD by pretreatment with sodium dithionite are rapidly oxidised by artemisinin to the parent flavins. When catalytic amounts of RF, FAD, and other flavins are reduced in,situ by excess BNAH or NAD(P)H in the presence of the artemisinins in the aqueous buffer, they are rapidly oxidised to the parent flavins with concomitant formation of two-electron reduction products from the artemisinins; regeneration of the reduced flavin by excess reductant maintains a catalytic cycle until the artemisinin is consumed. In preliminary experiments, we show that NADPH consumption in yeast GR with redox behaviour similar to that of parasite GR is enhanced by artemisinins, especially under aerobic conditions. Recombinant human GR is not affected. Artemisinins thus may act as antimalarial drugs by perturbing the redox balance within the malaria parasite, both by oxidising FADH2 in parasite GR or other parasite flavoenzymes, and by initiating autoxidation of the dihydroflavin by oxygen with generation of ROS. Reduction of the artemisinin is proposed to occur via hydride transfer from LMB or the dihydroflavin to O1 of the peroxide. This hitherto unrecorded reactivity profile conforms with known structure,activity relationships of artemisinins, is consistent with their known ability to generate ROS in,vivo, and explains the synergism between artemisinins and redox-active antimalarial drugs such as MB and doxorubicin. As the artemisinins appear to be relatively inert towards human GR, a putative model that accounts for the selective potency of artemisinins towards the malaria parasite also becomes apparent. Decisively, ferrous iron or carbon-centered free radicals cannot be involved, and the reactivity described herein reconciles disparate observations that are incompatible with the ferrous iron,carbon radical hypothesis for antimalarial mechanism of action. Finally, the urgent enquiry into the emerging resistance of the malaria parasite to artemisinins may now in one part address the possibilities either of structural changes taking place in parasite flavoenzymes that render the flavin cofactor less accessible to artemisinins or of an enhancement in the ability to use intra-erythrocytic human disulfide reductases required for maintenance of parasite redox balance. [source] | |||||||||||||||||||||||||