573 research outputs found

    Wireless intelligent sensors based in nanostructures with energy self-sufficiency to study the consequences of high temperatures in combustion motors

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    In this research are proposed the consequences of high temperatures in Internal Combustion Motors (ICM) as correlation of its performance according to give information of the ICM fault detector, which also can be useful for preventive maintenance. It was possible to achieve the proposed target because of it was designed a smart sensor based in nanostructures prepared over Anodic Aluminum Oxide (AAO) samples, which proportionated short response time and high robustness in the measurement tasks of the smart sensor, as well as, the designed sensor has the possibility to work by energy self-sufficiency and sending the measurement data to external users by wireless. In fact, it is waited that this research could be a support for researchers of ICM enhancement, who could look for new techniques of environment conditions cares in compensation to keep the balance between the useful energy obtained from ICM and the environment conditions, where are developed economical activities such as public transport or mining in Peru

    System identification analysis for an air compressor system and enhancement proposal by sensors based in nanostructures

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    An Air Compressor System is an equipment (mechanical system) which can transmit energy due to increase air pressure level of air flow that through it. This energy can be used in many applications, such as in drills for mining, adding air to tires on vehicles, spraying crops, etc. Therefore, it is necessary to know the mathematical model of an Air Compressor System to study all the thermodynamical variables: “Temperature, Pressure, Air Flow” which let to get a formalized explanation of the energy transfer through this equipment. Furthermore it is described that Air Compressor System can be enhanced while it uses sensors/actuators based in nanostructures

    Optimal Analysis for the Enhancement in the Thermal Variables Measurement by Smart and Modular Solid State Sensors

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    The proposed research aims to analyze and optimize the measurement of thermal physical variables during the operation of a hydrogen combustion engine. The optimal measurement of the flow, temperature, pressure, and volume is given over the hydrogen, which is the main fuel of the studied combustion motor. Hence, the success of the measurement is based on the polynomial analysis of the combustion motor operation, which needs nonlinear algorithms to get the optimal correlation of the measured physical variables as well as a high robustness and short response time during the transduction of the measured physical variable, which is achieved as a consequence of the anodic aluminum oxide (AAO) amorphous nanostructures properties that are modular solid state integration of the designed smart sensor. The short response time and high robustness is a good advantage for the designed smart sensor since it gives more time to execute sophisticated algorithms in order to get the optimal physical variables measurement. In fact, the proposed smart sensor keeps the possibility to be modular and solid state for the interaction with the hydrogen fuel as well as recognizing the presence of other molecules mixed in the fluid, which can alarm the user who is able to recognize whether it is joined oxygen or carbon residues. Therefore, the proposed research work toward a good compromise to care for the environment condition based on a cleaner combustion motor operation

    Illness perceptions and explanatory models of viral hepatitis B & C among immigrants and refugees: a narrative systematic review.

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    © 2015 Owiti et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.BACKGROUND: Hepatitis B and C (HBV, HCV) infections are associated with high morbidity and mortality. Many countries with traditionally low prevalence (such as UK) are now planning interventions (screening, vaccination, and treatment) of high-risk immigrants from countries with high prevalence. This review aimed to synthesise the evidence on immigrants' knowledge of HBV and HCV that might influence the uptake of clinical interventions. The review was also used to inform the design and successful delivery of a randomised controlled trial of targeted screening and treatment. METHODS: Five databases (PubMed, CINHAL, SOCIOFILE, PsycINFO & Web of Science) were systematically searched, supplemented by reference tracking, searches of selected journals, and of relevant websites. We aimed to identify qualitative and quantitative studies that investigated knowledge of HBV and HCV among immigrants from high endemic areas to low endemic areas. Evidence, extracted according to a conceptual framework of Kleinman's explanatory model, was subjected to narrative synthesis. We adapted the PEN-3 model to categorise and analyse themes, and recommend strategies for interventions to influence help-seeking behaviour. RESULTS: We identified 51 publications including quantitative (n = 39), qualitative (n = 11), and mixed methods (n = 1) designs. Most of the quantitative studies included small samples and had heterogeneous methods and outcomes. The studies mainly concentrated on hepatitis B and ethnic groups of South East Asian immigrants residing in USA, Canada, and Australia. Many immigrants lacked adequate knowledge of aetiology, symptoms, transmission risk factors, prevention strategies, and treatment, of hepatitis HBV and HCV. Ethnicity, gender, better education, higher income, and English proficiency influenced variations in levels and forms of knowledge. CONCLUSION: Immigrants are vulnerable to HBV and HCV, and risk life-threatening complications from these infections because of poor knowledge and help-seeking behaviour. Primary studies in this area are extremely diverse and of variable quality precluding meta-analysis. Further research is needed outside North America and Australia

    Metabolic Effects Associated with ICS in Patients with COPD and Comorbid Type 2 Diabetes: A Historical Matched Cohort Study

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    Background Management guidelines for chronic obstructive pulmonary disease (COPD) recommend that inhaled corticosteroids (ICS) are prescribed to patients with the most severe symptoms. However, these guidelines have not been widely implemented by physicians, leading to widespread use of ICS in patients with mild-to-moderate COPD. Of particular concern is the potential risk of worsening diabetic control associated with ICS use. Here we investigate whether ICS therapy in patients with COPD and comorbid type 2 diabetes mellitus (T2DM) has a negative impact on diabetic control, and whether these negative effects are dose-dependent. Methods and Findings This was a historical matched cohort study utilising primary care medical record data from two large UK databases. We selected patients aged >= 40 years with COPD and T2DM, prescribed ICS (n = 1360) or non-ICS therapy (n = 2642) between 2008 and 2012. The primary endpoint was change in HbA(1c) between the baseline and outcome periods. After 1:1 matching, each cohort consisted of 682 patients. Over the 12-18-month outcome period, patients prescribed ICS had significantly greater increases in HbA1c values compared with those prescribed non-ICS therapies; adjusted difference 0.16% (95% confidence interval [Cl]: 0.05-0.27%) in all COPD patients, and 0.25% (95% Cl: 0.10-0.40%) in mild-to-moderate COPD patients. Patients in the ICS cohort also had significantly more diabetes-related general practice visits per year and received more frequent glucose strip prescriptions, compared with those prescribed non-ICS therapies. Patients prescribed higher cumulative doses of ICS (> 250 mg) had greater odds of increased HbA(1c) and/or receiving additional antidiabetic medication, and increased odds of being above the Quality and Outcomes Framework (QOF) target for HbA1c levels, compared with those prescribed lower cumulative doses ( Conclusion For patients with COPD and comorbid T2DM, ICS therapy may have a negative impact on diabetes control. Patients prescribed higher cumulative doses of ICS may be at greater risk of diabetes progression

    Effect of Low Molecular Weight Heparins (LMWHs) on antiphospholipid Antibodies (aPL)-mediated inhibition of endometrial angiogenesis

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    Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by vascular thrombosis and/or pregnancy morbidity in the presence of circulating antiphospholipid antibodies (aPL). Different pathogenic mechanisms for aPL-mediated pregnancy failure have been proposed. In particular a direct effect of aPL on both maternal and fetal side of the placental tissue has been reported, since their reactivity with \u3b22-glycoprotein I (\u3b22GPI) makes them adhere to trophoblast and human endometrial endothelial cell (HEEC) membranes. \u3b22GPI can be recognized by aPL that, once bound, interfere with both trophoblast functions and with the HEEC differentiation.APS patients can be successfully treated with Low Molecular Weight Heparin (LMWH). Recent reports suggest that LMWH acts through mechanisms alternative to its well known anticoagulant effect, because of its ability to bind \u3b22GPI. In our previous studies, we showed that LMWH is able to reduce the aPL binding to trophoblasts and restore cell invasiveness and differentiation. So far, however, no study has described its effects on endometrial angiogenesis.The aim of our research was to evaluate whether two LMWHs, tinzaparin and enoxaparin, have an effect on the aPL-inhibited endometrial angiogenesis. This prompted us to investigate: (i) in vitro HEEC angiogenesis through a Matrigel assay; (ii) VEGF secretion by ELISA; (iii) matrix metalloproteinase-2 (MMP-2) activity by gelatin zymography; (iv) Nuclear Factor-\u3baB (NF-\u3baB) DNA binding activity by colorimetric assay; (v) STAT-3 activation by a sandwich-ELISA kit. Furthermore, using an in vivo murine model we investigated the LMWHs effects on angiogenesis.We demonstrated that the addition of LMWHs prevents aPL-inhibited HEEC angiogenesis, both in vitro and in vivo, and is able to restore the aPL inhibited NF-\u3baB and/or STAT-3 activity, the VEGF secretion and the MMPs activity.The demonstration of a beneficial role for LMWHs on the aPL-inhibited HEEC angiogenesis might provide additional mechanisms whereby this treatment protects early pregnancy in AP

    Modulation of Syndecan-1 Shedding after Hemorrhagic Shock and Resuscitation

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    The early use of fresh frozen plasma as a resuscitative agent after hemorrhagic shock has been associated with improved survival, but the mechanism of protection is unknown. Hemorrhagic shock causes endothelial cell dysfunction and we hypothesized that fresh frozen plasma would restore endothelial integrity and reduce syndecan-1 shedding after hemorrhagic shock. A prospective, observational study in severely injured patients in hemorrhagic shock demonstrated significantly elevated levels of syndecan-1 (554±93 ng/ml) after injury, which decreased with resuscitation (187±36 ng/ml) but was elevated compared to normal donors (27±1 ng/ml). Three pro-inflammatory cytokines, interferon-γ, fractalkine, and interleukin-1β, negatively correlated while one anti-inflammatory cytokine, IL-10, positively correlated with shed syndecan-1. These cytokines all play an important role in maintaining endothelial integrity. An in vitro model of endothelial injury then specifically examined endothelial permeability after treatment with fresh frozen plasma orlactated Ringers. Shock or endothelial injury disrupted junctional integrity and increased permeability, which was improved with fresh frozen plasma, but not lactated Ringers. Changes in endothelial cell permeability correlated with syndecan-1 shedding. These data suggest that plasma based resuscitation preserved endothelial syndecan-1 and maintained endothelial integrity, and may help to explain the protective effects of fresh frozen plasma after hemorrhagic shock

    The ATLAS SCT Optoelectronics and the Associated Electrical Services

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    The requirements for the optical links of the ATLAS SCT are described. From the individual detector modules to the first patch panel, the electrical services are integrated with the optical links to aid in mechanical design, construction and integration. The system architecture and critical elements of the system are described. The optical links for the ATLAS SCT have been assembled and mounted onto the carbon fibre support structures. The performance of the system as measured during QA is summarised and compared to the final performance obtained after mounting modules onto the support structures
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