6,213 research outputs found

    Evidence for heat losses via party wall cavities in masonry construction

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    This paper presents empirical evidence and analysis that supports the existence of a significant heat loss mechanism resulting from air movement through cavities in party walls in masonry construction. A range of heat loss experiments were undertaken as part of the Stamford Brook housing field trial in Altrincham in the United Kingdom. Co-heating tests showed a large discrepancy between the predicted and measured whole house heat loss coefficients. Analysis of the co-heating results, along with internal temperature data, thermal imaging and a theoretical analysis indicated that the most likely explanation for the discrepancy was bypassing of the thermal insulation via the uninsulated party wall cavities. The data show that such a bypass mechanism is potentially the largest single contributor to heat loss in terraced dwellings built to the 2006 revision of the Building Regulations. A comparable convective heat bypass associated with masonry party walls was identified in the late 1970s during the course of the Twin Rivers Project in the United States, albeit in a somewhat different construction from that used at Stamford Brook. A similar effect was also reported in the United Kingdom in the mid 1990s. However, it appears that no action was taken at that time either to confirm the results, to develop any technical solutions, or to amend standards for calculating heat losses from buildings. Current conventions for heat loss calculations in the United Kingdom do not take account of heat losses associated with party walls and it is suggested by the authors that such conventions may need to be updated to take account of the effect described in this paper. In the final part of the paper, the authors propose straightforward solutions to prevent bypassing of roof insulation via party walls by for example filling the cavity of the party wall with mineral fibre insulation, or by inserting a cavity closer across the cavity in the plane of the roof insulation.Practical application: The heat bypass mechanism described in this paper is believed by the authors to contribute to a significant proportion of heat loss from buildings in the UK constructed with clear cavities such as those found in separating walls between cavity masonry dwellings. It is proposed that relatively simple design changes could be undertaken to eliminate such heat loss pathways from new buildings. In addition, simple and cost effective measures are envisaged that could be used to minimise or eliminate the bypass from existing buildings. Such an approach could give rise to a significant reduction in carbon emissions from UK housing

    Developing Future UK Energy Performance Standards: The St Nicholas Court project, Final Report

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    The St Nicholas Court Project was set up to explore the implications of an enhanced energy performance standard for new housing for the design, construction and performance of timber framed dwellings. The energy performance standard, EPS08, is modelled on proposals made by the DETR in June 2000 for a possible review of Part L of the Building Regulations in the second half of the present decade. The overall goal of the project was to support the next revision of Part L through an enhanced body of qualitative and quantitative evidence on options and impacts. The seeds of the project were contained in a report – Towards Sustainable Housing - commissioned by Joseph Rowntree Foundation at the start of the last review of this part of the Building Regulations. The project itself has been based on the St Nicholas Court Development which involves the design and construction of a group of 18 low energy and affordable dwellings on a brown field site in York (see site plan below). The research project was established in two stages. Initial funding was provided by the Joseph Rowntree Foundation in the spring of 1999. This ensured the involvement of the research team from the outset of the development process. Additional funding was provided from late 2000 by the Housing Corporation and by the DETR through the Partners in Innovation programme (responsibility for which now lies with the DTI). The research project was originally divided into five phases – project definition, design, construction, occupation, and communication and dissemination. Delays in site acquisition initially allowed the design phase to be extended, but ultimately forced the abandonment of the construction and occupation phases, and the scaling down of the communication and dissemination phase. Despite the delays, the development itself will now go ahead, with construction starting in mid-2003

    Evaluating the impact of an enhanced energy performance standard on load-bearing masonry domestic construction: Understanding the gap between designed and real performance: lessons from Stamford Brook.

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    This report is aimed at those with interests in the procurement, design and construction of new dwellings both now and in the coming years as the Government’s increasingly stringent targets for low and zero carbon housing approach. It conveys the results of a research project, carried out between 2001 and 2008, that was designed to evaluate the extent to which low carbon housing standards can be achieved in the context of a large commercial housing development. The research was led by Leeds Metropolitan University in collaboration with University College London and was based on the Stamford Brook development in Altrincham, Cheshire. The project partners were the National Trust, Redrow and Taylor Wimpey and some 60 percent of the planned 700 dwelling development has been completed up to June 2008. As the UK house building industry and its suppliers grapple with the challenges of achieving zero carbon housing by 2016, the lessons arising from this project are timely and of considerable value. Stamford Brook has demonstrated that designing masonry dwellings to achieve an enhanced energy standard is feasible and that a number of innovative approaches, particularly in the area of airtightness, can be successful. The dwellings, as built, exceed the Building Regulations requirements in force at the time but tests on the completed dwellings and longer term monitoring of performance has shown that, overall, energy consumption and carbon emissions, under standard occupancy, are around 20 to 25 percent higher than design predictions. In the case of heat loss, the discrepancy can be much higher. The report contains much evidence of considerable potential but points out that realising the design potential requires a fundamental reappraisal of processes within the industry from design and construction to the relationship with its supply chain and the development of the workforce. The researchers conclude that, even when builders try hard, current mainstream technical and organisational practices together with industry cultures present barriers to consistent delivery of low and zero carbon performance. They suggest that the underlying reasons for this are deeply embedded at all levels of the house building industry. They point out also that without fundamental change in processes and cultures, technological innovations, whether they be based on traditional construction or modern methods are unlikely to reach their full potential. The report sets out a series of wide ranging implications for new housing in the UK, which are given in Chapter 14 and concludes by firmly declaring that cooperation between government, developers, supply chains, educators and researchers will be crucial to improvement. The recommendations in this report are already being put into practice by the researchers at Leeds Metropolitan University and University College London in their teaching and in further research projects. The implications of the work have been discussed across the industry at a series of workshops undertaken in 2008 as part of the LowCarb4Real project (see http://www.leedsmet.ac.uk/as/cebe/projects/lowcarb4real/index.htm). In addition, the learning is having an impact on the work of the developers (Redrow and Taylor Wimpey) who, with remarkable foresight and enthusiasm, hosted the project. This report seeks to make the findings more widely available and is offered for consideration by everyone who has a part to play in making low and zero carbon housing a reality

    Countering Social Engineering through Social Media: An Enterprise Security Perspective

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    The increasing threat of social engineers targeting social media channels to advance their attack effectiveness on company data has seen many organizations introducing initiatives to better understand these vulnerabilities. This paper examines concerns of social engineering through social media within the enterprise and explores countermeasures undertaken to stem ensuing risk. Also included is an analysis of existing social media security policies and guidelines within the public and private sectors.Comment: Proceedings of The 7th International Conference on Computational Collective Intelligence Technologies and Applications (ICCCI 2015), LNAI, Springer, Vol. 9330, pp. 54-6

    Shared Information -- New Insights and Problems in Decomposing Information in Complex Systems

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    How can the information that a set X1,...,Xn{X_{1},...,X_{n}} of random variables contains about another random variable SS be decomposed? To what extent do different subgroups provide the same, i.e. shared or redundant, information, carry unique information or interact for the emergence of synergistic information? Recently Williams and Beer proposed such a decomposition based on natural properties for shared information. While these properties fix the structure of the decomposition, they do not uniquely specify the values of the different terms. Therefore, we investigate additional properties such as strong symmetry and left monotonicity. We find that strong symmetry is incompatible with the properties proposed by Williams and Beer. Although left monotonicity is a very natural property for an information measure it is not fulfilled by any of the proposed measures. We also study a geometric framework for information decompositions and ask whether it is possible to represent shared information by a family of posterior distributions. Finally, we draw connections to the notions of shared knowledge and common knowledge in game theory. While many people believe that independent variables cannot share information, we show that in game theory independent agents can have shared knowledge, but not common knowledge. We conclude that intuition and heuristic arguments do not suffice when arguing about information.Comment: 20 page

    Novel 2-amino-isoflavones exhibit aryl hydrocarbon receptor agonist or antagonist activity in a species/cell-specific context

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    The aryl hydrocarbon receptor (AhR) mediates the induction of a variety of xenobiotic metabolism genes. Activation of the AhR occurs through binding to a group of structurally diverse compounds, most notably dioxins, which are exogenous ligands. Isoflavones are part of a family which include some well characterised endogenous AhR ligands. This paper analysed a novel family of these compounds, based on the structure of 2-amino-isoflavone. Initially two luciferase-based cell models, mouse H1L6.1c2 and human HG2L6.1c3, were used to identify whether the compounds had AhR agonistic and/or antagonistic properties. This analysis showed that some of the compounds were weak agonists in mouse and antagonists in human. Further analysis of two of the compounds, Chr-13 and Chr-19, was conducted using quantitative real-time PCR in rat H4IIE and human MCF-7 cells. The results indicated that Chr-13 was an agonist in rat but an antagonist in human cells. Chr-19 was shown to be an agonist in rat but more interestingly, a partial agonist in human. Luciferase induction results not only revealed that subtle differences in the structure of the compound could produce species-specific differences in response but also dictated the ability of the compound to be an AhR agonist or antagonist. Substituted 2-amino-isoflavones represent a novel group of AhR ligands that must differentially interact with the AhR ligand binding domain to produce their species-specific agonist or antagonist activity and future ligand binding analysis and docking studies with these compounds may provide insights into the differential mechanisms of action of structurally similar compounds

    Investigating the association of rs2910164 with cancer predisposition in an Irish cohort.

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    IntroductionMicroRNAs (miRNAs) are small noncoding RNA molecules that exert post-transcriptional effects on gene expression by binding with cis-regulatory regions in target messenger RNA (mRNA). Polymorphisms in genes encoding miRNAs or in miRNA-mRNA binding sites confer deleterious epigenetic effects on cancer risk. miR-146a has a role in inflammation and may have a role as a tumour suppressor. The polymorphism rs2910164 in the MIR146A gene encoding pre-miR-146a has been implicated in several inflammatory pathologies, including cancers of the breast and thyroid, although evidence for the associations has been conflicting in different populations. We aimed to further investigate the association of this variant with these two cancers in an Irish cohort.MethodsThe study group comprised patients with breast cancer (BC), patients with differentiated thyroid cancer (DTC) and unaffected controls. Germline DNA was extracted from blood or from saliva collected using the DNA Genotek Oragene 575 collection kit, using crystallisation precipitation, and genotyped using TaqMan-based PCR. Data were analysed using SPSS, v22.ResultsThe total study group included 1516 participants. This comprised 1386 Irish participants; 724 unaffected individuals (controls), 523 patients with breast cancer (BC), 136 patients with differentiated thyroid cancer (DTC) and three patients with dual primary breast and thyroid cancer. An additional cohort of 130 patients with DTC from the South of France was also genotyped for the variant. The variant was detected with a minor allele frequency (MAF) of 0.19 in controls, 0.22 in BC and 0.27 and 0.26 in DTC cases from Ireland and France, respectively. The variant was not significantly associated with BC (per allele odds ratio = 1.20 (0.98-1.46), P  = 0.07), but was associated with DTC in Irish patients (per allele OR = 1.59 (1.18-2.14), P = 0.002).ConclusionThe rs2910164 variant in MIR146A is significantly associated with DTC, but is not significantly associated with BC in this cohort

    Portal vein embolization versus dual vein embolization for management of the future liver remnant in patients undergoing major hepatectomy: meta-analysis

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    BACKGROUND: This meta-analysis aimed to compare progression to surgery, extent of liver hypertrophy, and postoperative outcomes in patients planned for major hepatectomy following either portal vein embolization (PVE) or dual vein embolization (DVE) for management of an inadequate future liver remnant (FLR). METHODS: An electronic search was performed of MEDLINE, Embase, and PubMed databases using both medical subject headings (MeSH) and truncated word searches. Articles comparing PVE with DVE up to January 2022 were included. Articles comparing sequential DVE were excluded. ORs, risk ratios, and mean difference (MD) were calculated using fixed and random-effects models for meta-analysis. RESULTS: Eight retrospective studies including 523 patients were included in the study. Baseline characteristics between the groups, specifically, age, sex, BMI, indication for resection, and baseline FLR (ml and per cent) were comparable. The percentage increase in hypertrophy was larger in the DVE group, 66 per cent in the DVE group versus 27 per cent in the PVE group, MD 39.07 (9.09, 69.05) (P = 0.010). Significantly fewer patients failed to progress to surgery in the DVE group than the PVE group, 13 per cent versus 25 per cent respectively OR 0.53 (0.31, 0.90) (P = 0.020). Rates of post-hepatectomy liver failure 13 per cent versus 22 per cent (P = 0.130) and major complications 20 per cent versus 28 per cent (Clavien–Dindo more than IIIa) (P = 0.280) were lower. Perioperative mortality was lower with DVE, 1 per cent versus 10 per cent (P = 0.010). CONCLUSION: DVE seems to produce a greater degree of hypertrophy of the FLR than PVE alone which translates into more patients progressing to surgery. Higher quality studies are needed to confirm these results

    The impacts of precision livestock farming tools on the greenhouse gas emissions of an average Scottish dairy farm

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    Precision livestock farming (PLF) tools are increasingly used in daily herd management to improve health, welfare, and overall production. While not intended to reduce greenhouse gas (GHG) emissions on farm, PLF tools can do so indirectly by improving overall efficiency, thereby reducing the emissions per unit of product. This work modelled the potential effects of commercially available PLF tools on whole enterprise and product emissions of two average Scottish dairy farm systems (an 8,000  L and 10,000  L herd) using the Agrecalc carbon foot printing tool. Scenarios modelled included an improvement infertility and an improvement in fertility and yield from the introduction of an accelerometer-based sensor, and an improvement in health from introduction of an accelerometer-based sensor, with and without the use of management interventions. Use of a sensor intended to improve fertility had the large streduction in total emissions (kg CO2e) of −1.42% for a 10,000  L farm, with management changes applied. The largest reduction in emissions from milk production (kg CO2e) of −2.31% was observed via fertility technology application in an 8,000  L farm, without management changes. The largest reduction in kg CO2e per kg fat and protein corrected milk of −6.72% was observed from an improvement in fertility and yield in a 10,000  L herd, with management changes. This study has highlighted the realistic opportunities available to dairy farmers in low and high input dairy systems to reduce their emissions through adoption of animal mounted PLF technologies

    Efficacy of an intensive outpatient rehabilitation program in alcoholism: Predictors of outcome 6 months after treatment

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    Treatment of alcohol-dependent patients was primarily focused on inpatient settings in the past decades. The efficacy of these treatment programs has been evaluated in several studies and proven to be sufficient. However, with regard to the increasing costs in public healthcare systems, questions about alternative treatment strategies have been raised. Meanwhile, there is growing evidence that outpatient treatment might be comparably effective as inpatient treatment, at least for subgroups of alcohol dependents. On that background, the present study aimed to evaluate the efficacy of a high-structured outpatient treatment program in 103 alcohol-dependent patients. 74 patients (72%) terminated the outpatient treatment regularly. At 6 months' follow-up, 95% patients were successfully located and personally re-interviewed. Analyses revealed that 65 patients (64%) were abstinent at the 6-month follow-up evaluation and 37 patients ( 36%) were judged to be non-abstinent. Pretreatment variables which were found to have a negative impact (non-abstinence) on the 6-month outcome after treatment were a higher severity of alcohol dependence measured by a longer duration of alcohol dependence, a higher number of prior treatments and a stronger alcohol craving (measured by the Obsessive Compulsive Drinking Scale). Further patients with a higher degree of psychopathology measured by the Beck Depression Inventory (depression) and State-Trait Anxiety Inventory (anxiety) relapsed more often. In summary, results of this study indicate a favorable outcome of socially stable alcohol-dependent patients and patients with a lower degree of depression, anxiety and craving in an intensive outpatient rehabilitation program
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