969 resultados para Energy expression
Resumo:
Energy auditing is an effective but costly approach for reducing the long-term energy consumption of buildings. When well-executed, energy loss can be quickly identified in the building structure and its subsystems. This then presents opportunities for improving energy efficiency. We present a low-cost, portable technology called "HeatWave" which allows non-experts to generate detailed 3D surface temperature models for energy auditing. This handheld 3D thermography system consists of two commercially available imaging sensors and a set of software algorithms which can be run on a laptop. The 3D model can be visualized in real-time by the operator so that they can monitor their degree of coverage as the sensors are used to capture data. In addition, results can be analyzed offline using the proposed "Spectra" multispectral visualization toolbox. The presence of surface temperature data in the generated 3D model enables the operator to easily identify and measure thermal irregularities such as thermal bridges, insulation leaks, moisture build-up and HVAC faults. Moreover, 3D models generated from subsequent audits of the same environment can be automatically compared to detect temporal changes in conditions and energy use over time.
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ZnO is a promising photoanode material for dye-sensitized solar cells (DSCs) due to its high bulk electron mobility and because different geometrical structures can easily be tailored. Although various strategies have been taken to improve ZnO-based DSC efficiencies, their performances are still far lower than TiO2 counterparts, mainly because low conductivity Zn2+–dye complexes form on the ZnO surfaces. Here, cone-shaped ZnO nanocrystals with exposed reactive O-terminated {101̅1} facets were synthesized and applied in DSC devices. The devices were compared with DSCs made from more commonly used rod-shaped ZnO nanocrystals where {101̅0} facets are predominantly exposed. When cone-shaped ZnO nanocrystals were used, DSCs sensitized with C218, N719, and D205 dyes universally displayed better power conversion efficiency, with the highest photoconversion efficiency of 4.36% observed with the C218 dye. First-principles calculations indicated that the enhanced DSCs performance with ZnO nanocone photoanodes could be attributed to the strength of binding between the dye molecules and reactive O-terminated {101̅1} ZnO facets and that more effective use of dye molecules occurred due to a significantly less dye aggregation on these ZnO surfaces compared to other ZnO facets.
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Server consolidation using virtualization technology has become an important technology to improve the energy efficiency of data centers. Virtual machine placement is the key in the server consolidation technology. In the past few years, many approaches to the virtual machine placement have been proposed. However, existing virtual machine placement approaches consider the energy consumption by physical machines only, but do not consider the energy consumption in communication network, in a data center. However, the energy consumption in the communication network in a data center is not trivial, and therefore should be considered in the virtual machine placement. In our preliminary research, we have proposed a genetic algorithm for a new virtual machine placement problem that considers the energy consumption in both physical machines and the communication network in a data center. Aiming at improving the performance and efficiency of the genetic algorithm, this paper presents a hybrid genetic algorithm for the energy-efficient virtual machine placement problem. Experimental results show that the hybrid genetic algorithm significantly outperforms the original genetic algorithm, and that the hybrid genetic algorithm is scalable.
Resumo:
Epigenetic regulation of gene expression is an important event for normal cellular homeostasis. Gene expression may be "switched" on or "turned" off via epigenetic means through adjustments in DNA architecture. These structural alterations result from changes to the DNA methylation status in addition to histone posttranslational modifications such as acetylation and methylation. Drugs which can alter the status of these epigenetic markers are currently undergoing clinical trials in a wide variety of diseases, including cancer.We illustrate the treatment of cell lines with histone deacetylase (HDi) and DNA methyltransferase inhibitors and the subsequent RNA isolation and reverse transcriptase polymerase chain reaction for several members of the CXC (ELR(+)) chemokine family. In addition we describe a chromatin immunoprecipitation assay to determine the association between chromatin transcription markers and DNA following pretreatment of cell cultures with an HDi, Trichostatin A (TSA). This assay allows us to determine whether treatment with TSA dynamically remodels the promoter region of our selected genes, as judged by the differences in the PCR product between our treated and untreated samples.
Resumo:
Background Thromboxane synthase (TXS) metabolizes prostaglandin H2 into thromboxanes, which are biologically active on cancer cells. TXS over-expression has been reported in a range of cancers, and associated with angiogenesis and poor outcome. TXS has been identified as a potential therapeutic target in NSCLC. This study examines a link between TXS expression, angiogenesis, and survival in NSCLC. Methods TXS and VEGF metabolite levels were measured in NSCLC serum samples (n=46) by EIA. TXB2 levels were correlated with VEGF. A 204-patient TMA was stained for TXS, VEGF, and CD-31 expression. Expression was correlated with a range of clinical parameters, including overall survival. TXS expression was correlated with VEGF and CD-31. Stable TXS clones were generated and the effect of overexpression on tumor growth and angiogenesis markers was examined in-vitro and in-vivo (xenograft mouse model). Results Serum TXB2 levels were correlated with VEGF (p<0.05). TXS and VEGF were expressed to a varying degree in NSCLC tissue. TXS was associated with VEGF (p<0.0001) and microvessel density (CD-31; p<0.05). TXS and VEGF expression levels were higher in adenocarcinoma (p<0.0001) and female patients (p<0.05). Stable overexpression of TXS increased VEGF secretion in-vitro. While no significant association with patient survival was observed for either TXS or VEGF in our patient cohort, TXS overexpression significantly (p<0.05) increased tumor growth in-vivo. TXS overexpression was also associated with higher levels of VEGF, microvessel density, and reduced apoptosis in xenograft tumors. Conclusion TXS promotes tumor growth in-vivo in NSCLC, an effect which is at least partly mediated through increased tumor angiogenesis.
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Estrogen receptor (ER)-β has been shown to possess a tumor suppressive effect, and is a potential target for cancer therapy. Using gene-expression meta-analysis of human malignant pleural mesothelioma, we identified an ESR2 (ERβ coding gene) signature. High ESR2 expression was strongly associated with low succinate dehydrogenase B (SDHB) (which encodes a mitochondrial respiratory chain complex II subunit) expression. We demonstrate that SDHB loss induced ESR2 expression, and that activated ERβ, by over-expression or by selective agonist stimulation, negatively affected oxidative phosphorylation compromising mitochondrial complex II and IV activity. This resulted in reduced mitochondrial ATP production, increased glycolysis dependence and impaired cell proliferation. The observed in vitro effects were phenocopied in vivo using a selective ERβ agonist in a mesothelioma mouse model. On the whole, our data highlight an unforeseen interaction between ERβ-mediated tumor suppression and energy metabolism that may be exploited to improve on the therapy for clinical management of malignant mesothelioma.
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Aging is associated with increased circulating pro-inflammatory and lower anti-inflammatory cytokines. Exercise training, in addition to improving muscle function, reduces these circulating pro-inflammatory cytokines. Yet, few studies have evaluated changes in the expression of cytokines within skeletal muscle after exercise training. The aim of the current study was to examine the expression of cytokines both at rest and following a bout of isokinetic exercise performed before and after 12 weeks of resistance exercise training in young (n = 8, 20.3 ± 0.8 yr) and elderly men (n = 8, 66.9 ± 1.6 yr). Protein expression of various cytokines was determined in muscle homogenates. The expression of MCP-1, IL-8 and IL-6 (which are traditionally classified as ‘pro-inflammatory’) increased substantially after acute exercise. By contrast, the expression of the anti-inflammatory cytokines IL-4, IL-10 and IL-13 increased only slightly (or not at all) after acute exercise. These responses were not significantly different between young and elderly men, either before or after 12 weeks of exercise training. However, compared with the young men, the expression of pro-inflammatory cytokines 2 h post exercise tended to be greater in the elderly men prior to training. Training attenuated this difference. These data suggest that the inflammatory response to unaccustomed exercise increases with age. Furthermore, regular exercise training may help to normalize this inflammatory response, which could have important implications for muscle regeneration and adaptation in the elderly.
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We previously showed that integrin alphavbeta3 overexpression and engagement by its ligand vitronectin increased adhesion, motility, and proliferation of human ovarian cancer cells. In search of differentially regulated genes involved in these tumor biological events, we previously identified the integrin-linked kinase (ILK) to be under control of alphavbeta3. In the present investigation we demonstrated significantly upregulated ILK protein as a function of alphavbeta3 in two ovarian cancer cell lines, OV-MZ-6 and OVCAR-3, and proved co-localization at the surface of alphavbeta3-overexpressing cells adherent to vitronectin. Increase of ILK protein was reflected by enhanced ILK promoter activity, an effect, which we further characterized with regard to transcriptional response elements involved. Abrogation of NF-kappaB/c-rel or p53 binding augmented ILK promoter activity and preserved induction by alphavbeta3. The AP1-mutant exhibited decreased promoter activity but was also still inducible by alphavbeta3. Disruption of the two DNA consensus motifs for Ets proteins led to divergent observations: mutation of the Ets motif at promoter position -462 bp did not significantly alter promoter activity but still allowed response to alphavbeta3. In contrast, disruption of the second Ets motif at position -85 bp did not only lead to slightly diminished promoter activity but also, in that case, abrogated ILK promoter induction by alphavbeta3. Subsequent co-transfection studies with ets-1 in the presence of the second Ets motif led to additional induction of ILK promoter activity. Taken together, these data suggest that ets-1 binding to the second Ets DNA motif strongly contributes to alphavbeta3-mediated ILK upregulation. By increasing ILK as an important integrin-proximal kinase, alphavbeta3 may promote its intracellular signaling and tumor biological processes arising thereof in favor of ovarian cancer metastasis.
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Despite having experienced rapid popularity over the past two decades, lifestyle journalism is still somewhat neglected by academic researchers. So far mostly explored as either part of wider lifestyle programming, particularly on television, or in terms of individual sub-fields, such as travel, fashion or food journalism, lifestyle journalism is in need of scholarly analysis particularly in the area of production, based on the increasing importance which the field has in influencing audiences’ ways of life. This study explores the professional views of 89 Australian and German lifestyle journalists through in-depth interviews in order to explore the ways in which they engage in processes of influencing audiences’ self-expression, identities and consumption behaviors. The article argues that through its work, lifestyle journalism is a significant shaper of identities in today’s consumer societies.
Resumo:
Ghrelin is a 28-amino acid peptide hormone produced predominantly in the stomach but also in a range of normal cell types and tumors, where it has endocrine, paracrine, and autocrine roles. Previously, we have demonstrated that ghrelin has proliferative and antiapoptotic effects in endometrial cancer cell lines, suggesting a potential role in promoting tumor growth. In the present study, we investigated the effect of ghrelin receptor, GHSR, and gene silencing in vitro and in vivo and characterized ghrelin and GHSR1a protein expression in human endometrial tumors. GHSR gene silencing was achieved in the Ishikawa and KLE endometrial cancer cell lines, using a lentiviral short-hairpin RNA targeting GHSR. The effects of GHSR1a knockdown were further analyzed in vivo using the Ishikawa cell line in a NOD/SCID xenograft model. Cell proliferation was reduced in cultured GHSR1a knockdown Ishikawa and KLE cells compared with scrambled controls in the absence of exogenously applied ghrelin and in response to exogenous ghrelin (1,000 nM). The tumor volumes were reduced significantly in GHSR1a knockdown Ishikawa mouse xenograft tumors compared with scrambled control tumours. Using immunohistochemistry, we demonstrated that ghrelin and GHSR1a are expressed in benign and cancerous glands in human endometrial tissue specimens, although there was no correlation between the intensity of staining and cancer grade. These data indicate that downregulation of GHSR expression significantly inhibits endometrial cancer cell line and mouse xenograft tumour growth. This is the first preclinical evidence that downregulation of GHSR may be therapeutic in endometrial cancer.
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G protein-coupled receptors (GPCRs) are critical for cardiovascular physiology. Cardiac cells express >100 nonchemosensory GPCRs, indicating that important physiological and potential therapeutic targets remain to be discovered. Moreover, there is a growing appreciation that members of the large, distinct taste and odorant GPCR families have specific functions in tissues beyond the oronasal cavity, including in the brain, gastrointestinal tract and respiratory system. To date, these chemosensory GPCRs have not been systematically studied in the heart. We performed RT-qPCR taste receptor screens in rodent and human heart tissues that revealed discrete subsets of type 2 taste receptors (TAS2/Tas2) as well as Tas1r1 and Tas1r3 (comprising the umami receptor) are expressed. These taste GPCRs are present in cultured cardiac myocytes and fibroblasts, and are enriched in myocytes, which we corroborated using in situ hybridization. Tas1r1 gene-targeted mice (Tas1r1Cre/Rosa26tdRFP) strikingly recapitulated these data. In vivo taste receptor expression levels were developmentally regulated in the postnatal period. Intriguingly, several Tas2rs were upregulated in cultured rat myocytes and in mouse heart in vivo following starvation. The discovery of taste GPCRs in the heart opens an exciting new field of cardiac research. We predict that these taste receptors may function as nutrient sensors in the heart.
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This paper proposes a new distributed coordination approach to make load leveling, using Energy Storage Units (ESUs) in LV network. The proposed distributed control strategy is based on consensus algorithm which shares the required active power equally among the ESUs with respect to their rating. To show the effectiveness of the proposed approach, a typical radial LV network is simulated as a case study.
Resumo:
To minimise the number of load sheddings in a microgrid (MG) during autonomous operation, islanded neighbour MGs can be interconnected if they are on a self-healing network and an extra generation capacity is available in the distributed energy resources (DER) of one of the MGs. In this way, the total load in the system of interconnected MGs can be shared by all the DERs within those MGs. However, for this purpose, carefully designed self-healing and supply restoration control algorithm, protection systems and communication infrastructure are required at the network and MG levels. In this study, first, a hierarchical control structure is discussed for interconnecting the neighbour autonomous MGs where the introduced primary control level is the main focus of this study. Through the developed primary control level, this study demonstrates how the parallel DERs in the system of multiple interconnected autonomous MGs can properly share the load of the system. This controller is designed such that the converter-interfaced DERs operate in a voltage-controlled mode following a decentralised power sharing algorithm based on droop control. DER converters are controlled based on a per-phase technique instead of a conventional direct-quadratic transformation technique. In addition, linear quadratic regulator-based state feedback controllers, which are more stable than conventional proportional integrator controllers, are utilised to prevent instability and weak dynamic performances of the DERs when autonomous MGs are interconnected. The efficacy of the primary control level of the DERs in the system of multiple interconnected autonomous MGs is validated through the PSCAD/EMTDC simulations considering detailed dynamic models of DERs and converters.