380 research outputs found
Extending the remit of evidence-based policing
Evidence-based policing (EBP) is an important strand of the UK’s College of Policing’s Police Education Qualifications Framework (PEQF), itself a component of a professionalisation agenda. This article argues that the two dominant approaches to EBP, experimental criminology and crime science, offer limited scope for the development of a comprehensive knowledge base for policing. Although both approaches share a common commitment to the values of science, each recognizes their limited coverage of policing topics. The fundamental difference between them is what each considers ‘best’ evidence. This article critically examines the generation of evidence by these two approaches and proposes an extension to the range of issues EBP should cover by utilizing a greater plurality of methods to exploit relevant research. Widening the scope of EBP would provide a broader foundational framework for inclusion in the PEQF and offers the potential for identifying gaps in the research, constructing blocks for knowledge building, and syllabus development in higher level police education
The Inflammatory Kinase MAP4K4 Promotes Reactivation of Kaposi's Sarcoma Herpesvirus and Enhances the Invasiveness of Infected Endothelial Cells
Kaposi's sarcoma (KS) is a mesenchymal tumour, which is caused by Kaposi's sarcoma herpesvirus (KSHV) and develops under inflammatory conditions. KSHV-infected endothelial spindle cells, the neoplastic cells in KS, show increased invasiveness, attributed to the elevated expression of metalloproteinases (MMPs) and cyclooxygenase-2 (COX-2). The majority of these spindle cells harbour latent KSHV genomes, while a minority undergoes lytic reactivation with subsequent production of new virions and viral or cellular chemo- and cytokines, which may promote tumour invasion and dissemination. In order to better understand KSHV pathogenesis, we investigated cellular mechanisms underlying the lytic reactivation of KSHV. Using a combination of small molecule library screening and siRNA silencing we found a STE20 kinase family member, MAP4K4, to be involved in KSHV reactivation from latency and to contribute to the invasive phenotype of KSHV-infected endothelial cells by regulating COX-2, MMP-7, and MMP-13 expression. This kinase is also highly expressed in KS spindle cells in vivo. These findings suggest that MAP4K4, a known mediator of inflammation, is involved in KS aetiology by regulating KSHV lytic reactivation, expression of MMPs and COX-2, and, thereby modulating invasiveness of KSHV-infected endothelial cells. © 2013 Haas et al
Scaffolded Active Learning: Nine Pedagogical Principles for Building a Modern Veterinary Curriculum
Celiac disease: how complicated can it get?
In the small intestine of celiac disease patients, dietary wheat gluten and similar proteins in barley and rye trigger an inflammatory response. While strict adherence to a gluten-free diet induces full recovery in most patients, a small percentage of patients fail to recover. In a subset of these refractory celiac disease patients, an (aberrant) oligoclonal intraepithelial lymphocyte population develops into overt lymphoma. Celiac disease is strongly associated with HLA-DQ2 and/or HLA-DQ8, as both genotypes predispose for disease development. This association can be explained by the fact that gluten peptides can be presented in HLA-DQ2 and HLA-DQ8 molecules on antigen presenting cells. Gluten-specific CD4+ T cells in the lamina propria respond to these peptides, and this likely enhances cytotoxicity of intraepithelial lymphocytes against the intestinal epithelium. We propose a threshold model for the development of celiac disease, in which the efficiency of gluten presentation to CD4+ T cells determines the likelihood of developing celiac disease and its complications. Key factors that influence the efficiency of gluten presentation include: (1) the level of gluten intake, (2) the enzyme tissue transglutaminase 2 which modifies gluten into high affinity binding peptides for HLA-DQ2 and HLA-DQ8, (3) the HLA-DQ type, as HLA-DQ2 binds a wider range of gluten peptides than HLA-DQ8, (4) the gene dose of HLA-DQ2 and HLA-DQ8, and finally,(5) additional genetic polymorphisms that may influence T cell reactivity. This threshold model might also help to understand the development of refractory celiac disease and lymphoma
Measuring persistence of implementation: QUERI Series
As more quality improvement programs are implemented to achieve gains in performance, the need to evaluate their lasting effects has become increasingly evident. However, such long-term follow-up evaluations are scarce in healthcare implementation science, being largely relegated to the "need for further research" section of most project write-ups. This article explores the variety of conceptualizations of implementation sustainability, as well as behavioral and organizational factors that influence the maintenance of gains. It highlights the finer points of design considerations and draws on our own experiences with measuring sustainability, framed within the rich theoretical and empirical contributions of others. In addition, recommendations are made for designing sustainability analyses
Limited genetic variation and structure in softshell clams (Mya arenaria) across their native and introduced range
Author Posting. © Springer, 2009. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Conservation Genetics 10 (2009): 803-814, doi:10.1007/s10592-008-9641-y.To offset declines in commercial landings of the softshell clam, Mya arenaria, resource
managers are engaged in extensive stocking of seed clams throughout its range in the
northwest Atlantic. Because a mixture of native and introduced stocks can disrupt locally
adapted genotypes, we investigated genetic structure in M. arenaria populations across
its current distribution to test for patterns of regional differentiation. We sequenced
mitochondrial cytochrome oxidase I (COI) for a total of 212 individuals from 12 sites in
the northwest Atlantic (NW Atlantic), as well as two introduced sites, the northeast
Pacific (NE Pacific) and the North Sea and Europe (NS Europe). Populations exhibited
extremely low genetic variation, with one haplotype dominating (65-100%) at all sites
sampled. Despite being introduced in the last 150-400 years, both NE Pacific and NS
Europe populations had higher diversity measures than those in the NW Atlantic and both
contained private haplotypes at frequencies of 10% to 27% consistent with their
geographic isolation. While significant genetic structure (FST = 0.159, p<0.001) was
observed between NW Atlantic and NS Europe, there was no evidence for genetic
structure across the pronounced environmental clines of the NW Atlantic. Reduced
genetic diversity in mtDNA combined with previous studies reporting reduced genetic
diversity in nuclear markers strongly suggests a recent population expansion in the NW
Atlantic, a pattern that may result from the retreat of ice sheets during Pleistocene glacial
periods. Lack of genetic diversity and regional genetic differentiation suggests that
present management strategies for the commercially important softshell clam are unlikely
to have a significant impact on the regional distribution of genetic variation, although the
possibility of disrupting locally adapted stocks cannot be excluded.This work was supported by NSF grants OCE-0326734 and OCE-0215905 to L.
Mullineaux and OCE- 0349177 (Biological Oceanography) to PHB
Effects of the fungicide metiram in outdoor freshwater microcosms: responses of invertebrates, primary producers and microbes
The ecological impact of the dithiocarbamate fungicide metiram was studied in outdoor freshwater microcosms, consisting of 14 enclosures placed in an experimental ditch. The microcosms were treated three times (interval 7 days) with the formulated product BAS 222 28F (Polyram®). Intended metiram concentrations in the overlying water were 0, 4, 12, 36, 108 and 324 μg a.i./L. Responses of zooplankton, macroinvertebrates, phytoplankton, macrophytes, microbes and community metabolism endpoints were investigated. Dissipation half-life (DT50) of metiram was approximately 1–6 h in the water column of the microcosm test system and the metabolites formed were not persistent. Multivariate analysis indicated treatment-related effects on the zooplankton (NOECcommunity = 36 μg a.i./L). Consistent treatment-related effects on the phytoplankton and macroinvertebrate communities and on the sediment microbial community could not be demonstrated or were minor. There was no evidence that metiram affected the biomass, abundance or functioning of aquatic hyphomycetes on decomposing alder leaves. The most sensitive populations in the microcosms comprised representatives of Rotifera with a NOEC of 12 μg a.i./L on isolated sampling days and a NOEC of 36 μg a.i./L on consecutive samplings. At the highest treatment-level populations of Copepoda (zooplankton) and the blue-green alga Anabaena (phytoplankton) also showed a short-term decline on consecutive sampling days (NOEC = 108 μg a.i./L). Indirect effects in the form of short-term increases in the abundance of a few macroinvertebrate and several phytoplankton taxa were also observed. The overall community and population level no-observed-effect concentration (NOECmicrocosm) was 12–36 μg a.i./L. At higher treatment levels, including the test systems that received the highest dose, ecological recovery of affected measurement endpoints was fast (effect period < 8 weeks)
Assessing Pro-environmental Behaviour in Relation to the Management of Pollution from Private Sewage Systems
Rapid Sampling of Molecular Motions with Prior Information Constraints
Proteins are active, flexible machines that perform a range of different
functions. Innovative experimental approaches may now provide limited partial
information about conformational changes along motion pathways of proteins.
There is therefore a need for computational approaches that can efficiently
incorporate prior information into motion prediction schemes. In this paper, we
present PathRover, a general setup designed for the integration
of prior information into the motion planning algorithm of rapidly exploring
random trees (RRT). Each suggested motion pathway comprises a sequence of
low-energy clash-free conformations that satisfy an arbitrary number of prior
information constraints. These constraints can be derived from experimental data
or from expert intuition about the motion. The incorporation of prior
information is very straightforward and significantly narrows down the vast
search in the typically high-dimensional conformational space, leading to
dramatic reduction in running time. To allow the use of state-of-the-art energy
functions and conformational sampling, we have integrated this framework into
Rosetta, an accurate protocol for diverse types of structural modeling. The
suggested framework can serve as an effective complementary tool for molecular
dynamics, Normal Mode Analysis, and other prevalent techniques for predicting
motion in proteins. We applied our framework to three different model systems.
We show that a limited set of experimentally motivated constraints may
effectively bias the simulations toward diverse predicates in an outright
fashion, from distance constraints to enforcement of loop closure. In
particular, our analysis sheds light on mechanisms of protein domain swapping
and on the role of different residues in the motion
A Research Agenda for Helminth Diseases of Humans: Modelling for Control and Elimination
Mathematical modelling of helminth infections has the potential to inform policy and guide research for the control and elimination of human helminthiases. However, this potential, unlike in other parasitic and infectious diseases, has yet to be realised. To place contemporary efforts in a historical context, a summary of the development of mathematical models for helminthiases is presented. These efforts are discussed according to the role that models can play in furthering our understanding of parasite population biology and transmission dynamics, and the effect on such dynamics of control interventions, as well as in enabling estimation of directly unobservable parameters, exploration of transmission breakpoints, and investigation of evolutionary outcomes of control. The Disease Reference Group on Helminth Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR), was given the mandate to review helminthiases research and identify research priorities and gaps. A research and development agenda for helminthiasis modelling is proposed based on identified gaps that need to be addressed for models to become useful decision tools that can support research and control operations effectively. This agenda includes the use of models to estimate the impact of large-scale interventions on infection incidence; the design of sampling protocols for the monitoring and evaluation of integrated control programmes; the modelling of co-infections; the investigation of the dynamical relationship between infection and morbidity indicators; the improvement of analytical methods for the quantification of anthelmintic efficacy and resistance; the determination of programme endpoints; the linking of dynamical helminth models with helminth geostatistical mapping; and the investigation of the impact of climate change on human helminthiases. It is concluded that modelling should be embedded in helminth research, and in the planning, evaluation, and surveillance of interventions from the outset. Modellers should be essential members of interdisciplinary teams, propitiating a continuous dialogue with end users and stakeholders to reflect public health needs in the terrain, discuss the scope and limitations of models, and update biological assumptions and model outputs regularly. It is highlighted that to reach these goals, a collaborative framework must be developed for the collation, annotation, and sharing of databases from large-scale anthelmintic control programmes, and that helminth modellers should join efforts to tackle key questions in helminth epidemiology and control through the sharing of such databases, and by using diverse, yet complementary, modelling approaches
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