955 resultados para Indoor radon


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Mobile ad hoc networking of dismounted combat personnel is expected to play an important role in the future of network-centric operations. High-speed, short-range, soldier-to-soldier wireless communications will be required to relay information on situational awareness, tactical instructions, and covert surveillance related data during special operations reconnaissance and other missions. This article presents some of the work commissioned by the U. K. Ministry of Defence to assess the feasibility of using 60 GHz millimeter-wave smart antenna technology to provide covert communications capable of meeting these stringent networking needs. Recent advances in RF front-end technology, alongside physical layer transmission schemes that could be employed in millimeter-wave soldier-mounted radio, are discussed. The introduction of covert communications between soldiers will require the development of a bespoke directive medium access layer. A number of adjustments to the IEEE 802.11 distribution coordination function that will enable directional communications are suggested. The successful implementation of future smart antenna technologies and direction of arrival-based protocols will be highly dependent on thorough knowledge of transmission channel characteristics prior to deployment. A novel approach to simulating dynamic soldier-to-soldier signal propagation using state-of-the-art animation-based technology developed for computer game design is described, and important channel metrics such as root mean square angle and delay spread for a team of four networked infantry soldiers over a range of indoor and outdoor environments is reported.

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Environmental (222)radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET alpha-particle irradiation initiate deleterious genetic consequences in both radiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single He-3(2+) particle traversal to a single cell, are sufficient to Induce RIGI Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (Rid, measured as delayed chromosome aberrations) Although this was not highly significant, it was possibly masked by high levels of intra-individual variation While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype (C) 2010 Elsevier B.V. All rights reserved.

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This paper aims at investigating architectural and urban heritage from the socio-cultural point of view, which stands on the human asset of traditional sites such as the hawari of old Cairo. It analyzes the social practice of everyday life in one of the oldest Cairene hawari, Haret al-Darb al-Asfar. The focus is on architectural and spatial organization of outdoor and indoor spaces that coordinate the spatial practices of local community. A daily monitoring of people’s activities and interviews was conducted in an investigation of how local people perceive their built environment between the house’s interior and the outdoor shared space. It emerges that people construct their own field of private spheres according to complex patterns of daily activities that are not in line with the classical segregation between private and public in Islamic cities. This paper reports that the harah is basically a construct of social spheres that are organized spatially by the flexible development of individual buildings over time and in response to changes in individuals’ needs and capabilities. In order to achieve sustainability in old urban quarters, the paper concludes, the focus should be directed towards the local organization of activities and a comprehensive upgrading of deteriorating buildings to match the changing needs of current population.

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The coupled heat, air and moisture transfer between building envelopes and indoor air is complicated, and has a significant influence on the indoor environment and the energy performance of buildings. In the paper, a model for predicting coupled multi-zone hygrothermal-airflow transfer is presented. Both heat and moisture transfer in the building envelope and multi-zone indoor airflow are simultaneously considered; their interactions are modeled. The coupled system model is implemented into Matlab–Simulink, and is validated by using a series of testing tools and experiments. The new program is applied to investigate the moisture transfer effect on indoor air humidity and building energy consumption in different climates (hot-humid, temperate and hot-dry climates). The results show that not accounting for hygrothermal effects in modeling will result in overestimation of energy costs for hot and humid climate situations and possible over sizing of plant leading to inefficient operation.

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In this letter, we investigate the distribution of the phase component of the complex received signal observed in practical experiments using body area networks. Two phase distributions, the recently proposed kappa-mu and eta-mu probability densities, which together encompass the most widely used fading models, namely Semi-Gaussian, Rayleigh, Hoyt, Rice, and Nakagami-m, have been compared with measurement data. The kappa-mu distribution has been found to provide the best fit over a range of on-body links, while the user was mobile. The experiments were carried out in two dissimilar indoor environments at opposite ends of the multipath spectrum. It has also been found that the uniform phase distribution has not arisen in anyone of the experiments.

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Eight indoor-reared crossbred sheep with no pre-exposure to Fasciola hepatica were infected, by oral gavage, with 200 metacercarial cysts of the triclabendazole (TCBZ)-susceptible Cullompton isolate of F. hepatica. Anthelmintic dosing occurred at 4 weeks post-infection with 10 mg/kg triclabendazole. Two treated sheep were euthanized at 48 h, 72 h and 96 h post-treatment with triclabendazole. Two control sheep were euthanized alongside the 48 h triclabendazole-treated sheep. Juvenile flukes were recovered from each of the sheeps’ liver and processed for scanning electron microscopy (SEM).

Flukes were still active 48 h post-treatment and displayed limited morphological disruption. There was some blebbing and sloughing of the tegument around the oral sucker. In several of the specimens, an extra layer had been deposited on the fluke surface, giving it a flattened appearance. At 72 h post-treatment, only one fluke remained alive and the disruption varied in degree. In the majority of flukes, there was severe swelling of the tegument, accompanied by isolated areas of flattening along the lateral margins of the flukes and in the tail region. Limited areas of sloughing occurred in the tail region. In more seriously affected specimens, the syncytium had been stripped away to reveal the basal lamina and some deeper lesions were also observed. By 96 h post-treatment, all the flukes were dead and were grossly disrupted. They were totally devoid of tegument and deep lesions exposed the internal tissues of the fluke.

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Background: The incidence rates of childhood onset type 1 diabetes are almost universally increasing across the globe but the aetiology of the disease remains largely unknown. We investigated whether birth order is associated with the risk of childhood diabetes by performing a pooled analysis of previous studies. Methods: Relevant studies published before January 2010 were identified from MEDLINE, Web of Science and EMBASE. Authors of studies provided individual patient data or conducted pre-specified analyses. Meta-analysis techniques were used to derive combined odds ratios (ORs), before and after adjustment for confounders, and investigate heterogeneity. Results: Data were available for 6 cohort and 25 case-control studies, including 11 955 cases of type 1 diabetes. Overall, there was no evidence of an association prior to adjustment for confounders. After adjustment for maternal age at birth and other confounders, a reduction in the risk of diabetes in second-or later born children became apparent [fully adjusted OR=0.90 95% confidence interval (CI) 0.83-0.98; P=0.02] but this association varied markedly between studies (I 2=67%). An a priori subgroup analysis showed that the association was stronger and more consistent in children <5years of age (n=25 studies, maternal age adjusted OR=0.84 95% CI 0.75, 0.93; I 2=23%). Conclusion: Although the association varied between studies, there was some evidence of a lower risk of childhood onset type 1 diabetes with increasing birth order, particularly in children aged <5 years. This finding could reflect increased exposure to infections in early life in later born children. Published by Oxford University Press on behalf of the International Epidemiological Association © The Author 2010; all rights reserved.

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The hawari of Cairo - narrow non-straight alleyways - are the basic urban units that have formed the medieval city since its foundation back in 969 AD. Until early in the C20th, they made up the primary urban divisions of the city and were residential in nature. Contemporary hawari, by contrast, are increasingly dominated by commercial and industrial activity. This medieval urban maze of extremely short, broken, zigzag streets and dead ends are defensible territories, powerful institutions, and important social systems. While the hawari have been studied as an exemplar for urban structure of medieval Islamic urbanism, and as individual building typologies, this book is the first to examine in detail the socio-spatial practice of the architecture of home in the city. It investigates how people live, communicate and relate to each other within their houses or shared spaces of the alleys, and in doing so, to uncover several new socio-spatial dimensions and meanings in this architectural form.

In an attempt to re-establish the link between architecture past and present, and to understand the changing social needs of communities, this book uncovers the notion of home as central to understand architecture in such a city with long history as Cairo. It firstly describes the historical development of the domestic spaces (indoor and outdoor), and provides an inclusive analysis of spaces of everyday activities in the hawari of old Cairo. It then broadens its analysis to other parts of the city, highlighting different customs and representations of home in the city at large. Cairo, in the context of this book, is represented as the most sophisticated urban centre in the Middle East with different and sometimes contrasting approaches to the architecture of home, as a practice and spatial system.

In order to analyse the complexity and interconnectedness of the components and elements of the hawari as a 'collective home', it layers its narratives of architectural and social developments as a domestic environment over the past two hundred years, and in doing so, explores the in-depth social meaning and performance of spaces, both private and public.

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Eight indoor-reared cross-bred sheep with no prior exposure to Fasciola hepatica were infected by oral gavage with 200 metacercarial cysts of the triclabendazole (TCBZ)-susceptible Cullompton isolate of F. hepatica. Twelve weeks after infection, sheep were treated with 10 mg/kg triclabendazole. Two sheep were euthanised per time period; at 48 h, 72 h and 96 h post-treatment (pt). Two untreated control sheep were euthanised at 96 h pt. Flukes were recovered from the liver and, if present, from the gall bladder of the sheep. They were processed for whole mount analysis, histology and transmission electron microscopy of the female reproductive system; specifically, the uterus, vitelline follicles. Mehlis' gland and ovary.

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This paper addresses the pose recovery problem of a particular articulated object: the human body. In this model-based approach, the 2D-shape is associated to the corresponding stick figure allowing the joint segmentation and pose recovery of the subject observed in the scene. The main disadvantage of 2D-models is their restriction to the viewpoint. To cope with this limitation, local spatio-temporal 2D-models corresponding to many views of the same sequences are trained, concatenated and sorted in a global framework. Temporal and spatial constraints are then considered to build the probabilistic transition matrix (PTM) that gives a frame to frame estimation of the most probable local models to use during the fitting procedure, thus limiting the feature space. This approach takes advantage of 3D information avoiding the use of a complex 3D human model. The experiments carried out on both indoor and outdoor sequences have demonstrated the ability of this approach to adequately segment pedestrians and estimate their poses independently of the direction of motion during the sequence. (c) 2008 Elsevier Ltd. All rights reserved.

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In this paper, a novel framework for visual tracking of human body parts is introduced. The approach presented demonstrates the feasibility of recovering human poses with data from a single uncalibrated camera by using a limb-tracking system based on a 2-D articulated model and a double-tracking strategy. Its key contribution is that the 2-D model is only constrained by biomechanical knowledge about human bipedal motion, instead of relying on constraints that are linked to a specific activity or camera view. These characteristics make our approach suitable for real visual surveillance applications. Experiments on a set of indoor and outdoor sequences demonstrate the effectiveness of our method on tracking human lower body parts. Moreover, a detail comparison with current tracking methods is presented.