1,805 research outputs found

    Evaluating the Effectiveness of CCTV in Baltimore, Maryland

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    This report reviews the results of an investigation into the effectiveness of public surveillance systems in Cherry Hill, Baltimore City, Maryland. Its chief objective is to discern whether closed circuit television (CCTV) cameras are a successful crime control measure and whether their implementation displaced crime or generated a diffusion of benefits to the areas outside a camera’s viewshed. Previous research on the efficacy of CCTV leaves much to be desired, and the debate is still inconclusive. Thus, this study attempts to move toward new ways of analyzing crime data gathered pre- and post-implementation of cameras in a given target area. To conduct this research, the investigation utilizes a combination of existing and new geographical information systems (GIS) spatial techniques to visualize and measure crime distribution and uses light detection and ranging (LiDAR) data to produce a precise mapping of a camera’s line of sight. Findings from each analytical method are compared, contrasted, and combined to provide rounded results. These findings suggest that the implementation of GIS techniques in crime mapping have huge potential and could provide innovative uses for CCTV within law enforcement crime control programs

    Spatial Analysis of Climate Driver Impacts on Sub-Saharan African Migration Patterns in Tanzania

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    Environmental problems resulting from climate change have generated negative impacts on climate-sensitive sectors of African economies. Coping with adverse situations, individuals and households adopt several strategies, including rural-urban migration. Previous literature has investigated the use of migration as a coping strategy to environmental factors. However, specific empirical assessment of links between migration and climatic factors with emphasis on spatial perspectives is not well studied. Accordingly, this study focuses on climatic driver influences on migration from statistical and spatial perspectives using logistic regression and Geographic Information Systems (GIS). We combined secondary data sets collected by the World Bank SLMS nationwide household surveys with geo-referenced sub-villages and historical gridded rainfall and temperature data. Results suggest a significant positive relationship between long-run precipitation and migration, while long-run temperature was statistically inconsequential. Results also suggest spatial patterns and climate change drivers are critical in understanding the migration determinants in Tanzania

    From pelvic radiation to social isolation: a qualitative study of survivors’ experiences of chronic bowel symptoms after pelvic radiotherapy

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    \ua9 2024, The Author(s).Purpose: We explored survivors’ experiences of chronic bowel symptoms following pelvic radiotherapy, strategies employed in living with these symptoms, effects on daily activities, and roles at home and in the workplace. Methods: Semi-structured interviews were conducted with 28 individuals (10 gynaecological, 14 prostate, four anal/rectal cancer survivors) who had completed pelvic radiotherapy at least six months prior to data collection and who had experience of bowel symptoms during this post-treatment period. Reflexive thematic analysis was undertaken. Results: We propose four themes describing a process leading from experience of symptoms to withdrawal from activities and roles. These are (1) losing control (the experience of unintended anal leakage or discharge); (2) experiencing embarrassment and fear (the experience of embarrassment or fear of embarrassment as a result of discharge becoming public); (3) managing and reacting (acting to reduce the likelihood of discharge or to prevent this becoming public); and (4) restriction and withdrawal (avoiding specific activities or situations so as to reduce or remove the risk of embarrassment). Returning to the workplace presented additional challenges across these themes. Conclusions: Impacts of chronic bowel symptoms can be severe. Survivors employ a variety of methods and strategies in living with their symptoms. Some of these support continued role fulfilment but some constitute a withdrawal from pre-treatment roles. Current healthcare provision and statutory protections fail to fully meet needs following pelvic radiotherapy. Implications for cancer survivors. There is a need to develop and implement evidence-based services and supported self-management programmes for survivors experiencing chronic bowel problems post-radiotherapy

    Lightweighting design optimisation for additively manufactured mirrors

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    Design for additive manufacture (AM; 3D printing) is significantly different than design for subtractive machining. Although there are some limitations on the designs that can be printed, the increase in the AM design-space removes some of the existing challenges faced by the traditional lightweight mirror designs; for example, sandwich mirrors are just as easy to fabricate as open-back mirrors via AM, and they provide an improvement in structural rigidity. However, the ability to print a sandwich mirror as a single component does come with extra considerations; such as orientation upon the build plate and access to remove any temporary support material. This paper describes the iterations in optimisation applied to the lightweighting of a small, 84 mm diameter by 20 mm height, spherical concave mirror intended for CubeSat applications. The initial design, which was fabricated, is discussed in terms of the internal lightweighting design and the design constraints that were imposed by printing and post-processing. Iterations on the initial design are presented; these include the use of topology optimisation to minimise the total internal strain energy during mirror polishing and the use of lattices combined with thickness variation i.e. having a thicker lattice in strategic support locations. To assess the suitability of each design, finite element analysis is presented to quantify the print-through of the lightweighting upon the optical surface for a given mass reduction

    Additively manufactured mirrors for CubeSats

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    Additive manufacturing (AM; 3D printing) is a fabrication process that builds an object layer-upon-layer and promotes the use of structures that would not be possible via subtractive machining. Prototype AM metal mirrors are increasingly being studied in order to exploit the advantage of the broad AM design-space to develop intricate lightweight structures that are more optimised for function than traditional open-back mirror lightweighting. This paper describes a UK Space Agency funded project to design and manufacture a series of lightweighted AM mirrors to fit within a 3 U CubeSat chassis. Five AM mirrors of identical design will be presented: two in aluminium (AlSi10Mg), two in nickel phosphorous (NiP) coated AlSi10Mg, and one in titanium (Ti64). For each material mirror pair, one is hand-polished (including the Ti64) and the other is diamond turned. Metrology data, surface form error and surface roughness, will be presented to compare and contrast the different materials and post-processing methods. To assess the presence of porosity, a frequent concern for AM materials, X-ray computed tomography measurements will be presented to highlight the location and density of pores within the mirror substrate; methods to mitigate the distribution of pores near the optical surface will be described. As a metric for success, the AlSi10Mg + NiP and AlSi10Mg mirrors should be suitable in terms of metrology data for visible and infrared applications respectively

    Laboratory and tentative interstellar detection of trans-methyl formate using the publicly available Green Bank Telescope PRIMOS survey

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    The rotational spectrum of the higher-energy trans conformational isomer of methyl formate has been assigned for the first time using several pulsed-jet Fourier transform microwave spectrometers in the 6-60 GHz frequency range. This species has also been sought toward the Sagittarius B2(N) molecular cloud using the publicly available PRIMOS survey from the Green Bank Telescope. We detect seven absorption features in the survey that coincide with laboratory transitions of trans-methyl formate, from which we derive a column density of 3.1 (+2.6, -1.2) \times 10^13 cm-2 and a rotational temperature of 7.6 \pm 1.5 K. This excitation temperature is significantly lower than that of the more stable cis conformer in the same source but is consistent with that of other complex molecular species recently detected in Sgr B2(N). The difference in the rotational temperatures of the two conformers suggests that they have different spatial distributions in this source. As the abundance of trans-methyl formate is far higher than would be expected if the cis and trans conformers are in thermodynamic equilibrium, processes that could preferentially form trans-methyl formate in this region are discussed. We also discuss measurements that could be performed to make this detection more certain. This manuscript demonstrates how publicly available broadband radio astronomical surveys of chemically rich molecular clouds can be used in conjunction with laboratory rotational spectroscopy to search for new molecules in the interstellar medium.Comment: 40 pages, 7 figures, 4 tables; accepted for publication in Ap

    Co-producing principles to guide health research: an illustrative case study from an eating disorder research clinic

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    There is significant value in co-produced health research, however power-imbalances within research teams can pose a barrier to people with lived experience of an illness determining the direction of research in that area. This is especially true in eating disorder research, where the inclusion of co-production approaches lags other research areas. Appealing to principles or values can serve to ground collaborative working. Despite this, there has not been any prior attempt to co-produce principles to guide the work of a research group and serve as a basis for developing future projects. The aim of this piece of work was to co-produce a set of principles to guide the conduct of research within our lived experience led research clinic, and to offer an illustrative case for the value of this as a novel co-production methodology. A lived experience panel were recruited to our eating disorder research group. Through an iterative series of workshops with the members of our research clinic (composed of a lived experience panel, clinicians, and researchers) we developed a set of principles which we agreed were important in ensuring both the direction of our research, and the way in which we wanted to work together. Six key principles were developed using this process. They were that research should aim to be: 1) real world—offering a clear and concrete benefit to people with eating disorders, 2) tailored—suitable for marginalised groups and people with atypical diagnoses, 3) hopeful—ensuring that hope for recovery was centred in treatment, 4) experiential—privileging the ‘voice’ of people with eating disorders, 5) broad—encompassing non-standard therapeutic treatments and 6) democratic—co-produced by people with lived experience of eating disorders. We reflect on some of the positives as well as limitations of the process, highlighting the importance of adequate funding for longer-term co-production approaches to be taken, and issues around ensuring representation of minority groups. We hope that other health research groups will see the value in co-producing principles to guide research in their own fields, and will adapt, develop, and refine this novel methodology

    Predicting tree distributions in an East African biodiversity hotspot : model selection, data bias and envelope uncertainty

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    The Eastern Arc Mountains (EAMs) of Tanzania and Kenya support some of the most ancient tropical rainforest on Earth. The forests are a global priority for biodiversity conservation and provide vital resources to the Tanzanian population. Here, we make a first attempt to predict the spatial distribution of 40 EAM tree species, using generalised additive models, plot data and environmental predictor maps at sub 1 km resolution. The results of three modelling experiments are presented, investigating predictions obtained by (1) two different procedures for the stepwise selection of predictors, (2) down-weighting absence data, and (3) incorporating an autocovariate term to describe fine-scale spatial aggregation. In response to recent concerns regarding the extrapolation of model predictions beyond the restricted environmental range of training data, we also demonstrate a novel graphical tool for quantifying envelope uncertainty in restricted range niche-based models (envelope uncertainty maps). We find that even for species with very few documented occurrences useful estimates of distribution can be achieved. Initiating selection with a null model is found to be useful for explanatory purposes, while beginning with a full predictor set can over-fit the data. We show that a simple multimodel average of these two best-model predictions yields a superior compromise between generality and precision (parsimony). Down-weighting absences shifts the balance of errors in favour of higher sensitivity, reducing the number of serious mistakes (i.e., falsely predicted absences); however, response functions are more complex, exacerbating uncertainty in larger models. Spatial autocovariates help describe fine-scale patterns of occurrence and significantly improve explained deviance, though if important environmental constraints are omitted then model stability and explanatory power can be compromised. We conclude that the best modelling practice is contingent both on the intentions of the analyst (explanation or prediction) and on the quality of distribution data; generalised additive models have potential to provide valuable information for conservation in the EAMs, but methods must be carefully considered, particularly if occurrence data are scarce. Full results and details of all species models are supplied in an online Appendix. (C) 2008 Elsevier B.V. All rights reserved

    A Humanized Pattern of Aromatase Expression is Associated with Mammary Hyperplasia in Mice

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    Aromatase is essential for estrogen production and is the target of aromatase inhibitors, the most effective endocrine treatment for postmenopausal breast cancer. Peripheral tissues in women, including the breast, express aromatase via alternative promoters. Female mice lack the promoters that drive aromatase expression in peripheral tissues; thus, we generated a transgenic humanized aromatase (Arom(hum)) mouse line containing a single copy of the human aromatase gene to study the link between aromatase expression in mammary adipose tissue and breast pathology. Arom(hum) mice expressed human aromatase, driven by the proximal human promoters II and I.3 and the distal promoter I.4, in breast adipose fibroblasts and myoepithelial cells. Estrogen levels in the breast tissue of Arom(hum) mice were higher than in wild-type mice, whereas circulating levels were similar. Arom(hum) mice exhibited accelerated mammary duct elongation at puberty and an increased incidence of lobuloalveolar breast hyperplasia associated with increased signal transducer and activator of transcription-5 phosphorylation at 24 and 64 wk. Hyperplastic epithelial cells showed remarkably increased proliferative activity. Thus, we demonstrated that the human aromatase gene can be expressed via its native promoters in a wide variety of mouse tissues and in a distribution pattern nearly identical to that of humans. Locally increased tissue levels, but not circulating levels, of estrogen appeared to exert hyperplastic effects on the mammary gland. This novel mouse model will be valuable for developing tissue-specific aromatase inhibition strategies
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