2,165 research outputs found

    Relationship between nano-architectured Ti1−xCux thin film and electrical resistivity for resistance temperature detectors

    Get PDF
    Ti1−xCux thin films were produced by the glancing angle deposition technique (GLAD) for resistance temperature measurements. The deposition angle was fixed at α = 0° to growth columnar structures and α = 45° to growth zigzag structures. The Ti-to-Cu atomic concentration was tuned from 0 to 100 at.% of Cu in order to optimize the temperature coefficient of resistance (TCR) value. Increasing the amount of Cu in the Ti1−xCux thin films, the electrical conductivity was gradually changed from 4.35 to 7.87 × 105 Ω−1 m−1. After thermal “stabilization,” the zigzag structures of Ti1−xCux films induce strong variation of the thermosensitive response of the materials and exhibited a reversible resistivity versus temperature between 35 and 200 °C. The results reveal that the microstructure has an evident influence on the overall response of the films, leading to values of TCR of 8.73 × 10−3 °C−1 for pure copper films and of 4.38 × 10−3 °C−1 for a films of composition Ti0.49Cu0.51. These values are very close to the ones reported for the bulk platinum (3.93 × 10−3 °C−1), which is known to be one of the best material available for these kind of temperature-related applications. The non-existence of hysteresis in the electrical response of consecutive heating and cooling steps indicates the viability of these nanostructured zigzag materials to be used as thermosensitive sensors.Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013 and Project PTDC/EEI-SII/5582/2014. A. Ferreira and C. Lopes thanks the FCT for Grant SFRH/BPD/102402/2014 and SFRH/BD/103373/2014. The authors thank financial support from the Basque Government Industry Department under the ELKARTEK Programinfo:eu-repo/semantics/publishedVersio

    Inference of gene regulatory networks from time series by Tsallis entropy

    Get PDF
    Background: The inference of gene regulatory networks (GRNs) from large-scale expression profiles is one of the most challenging problems of Systems Biology nowadays. Many techniques and models have been proposed for this task. However, it is not generally possible to recover the original topology with great accuracy, mainly due to the short time series data in face of the high complexity of the networks and the intrinsic noise of the expression measurements. In order to improve the accuracy of GRNs inference methods based on entropy (mutual information), a new criterion function is here proposed. Results: In this paper we introduce the use of generalized entropy proposed by Tsallis, for the inference of GRNs from time series expression profiles. The inference process is based on a feature selection approach and the conditional entropy is applied as criterion function. In order to assess the proposed methodology, the algorithm is applied to recover the network topology from temporal expressions generated by an artificial gene network (AGN) model as well as from the DREAM challenge. The adopted AGN is based on theoretical models of complex networks and its gene transference function is obtained from random drawing on the set of possible Boolean functions, thus creating its dynamics. On the other hand, DREAM time series data presents variation of network size and its topologies are based on real networks. The dynamics are generated by continuous differential equations with noise and perturbation. By adopting both data sources, it is possible to estimate the average quality of the inference with respect to different network topologies, transfer functions and network sizes. Conclusions: A remarkable improvement of accuracy was observed in the experimental results by reducing the number of false connections in the inferred topology by the non-Shannon entropy. The obtained best free parameter of the Tsallis entropy was on average in the range 2.5 <= q <= 3.5 (hence, subextensive entropy), which opens new perspectives for GRNs inference methods based on information theory and for investigation of the nonextensivity of such networks. The inference algorithm and criterion function proposed here were implemented and included in the DimReduction software, which is freely available at http://sourceforge.net/projects/dimreduction and http://code.google.com/p/dimreduction/.Fundacao de Amparo e Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Coordenacao de Aperfeicofamento de Pessoal de Nivel Superior (CAPES)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq

    A canonical correlation analysis of the association between carcass and ham traits in pigs used to produce dry-cured ham

    Get PDF
    The association between carcass and ham traits in a pig population used to produce dry-cured ham was studied using canonical correlation analysis. The carcass traits examined were hot carcass weight (HCW), backfat thickness (BT) and loin depth (LD), and the ham traits studied were gross ham weight (GHW), trimmed ham weight (THW), ham inner layer fat thickness (HIFT), ham outer layer fat thickness (HOFT), pH (pH) and the Göfo value. Carcass and ham traits are not independent. The canonical correlations (r) between the carcass and ham traits at 130 kg were 0.77, 0.24 and 0.20 for the first, second and third canonical pair, respectively, and were all significant (p < 0.01) by the Wilks test. The corresponding canonical correlations between the three canonical variate pairs for the carcass and ham traits at 160 kg were 0.88, 0.42 and 0.14, respectively (p < 0.05 for all, except the third). The correlations between the traits and their canonical variate showed an association among HCW, GHW and THW, and between BT and HOFT. These results indicate that carcass traits should be used to cull pigs that are not suitable for dry-cured ham production

    Five new species of Ectobiidae (Blattodea) collected in the Reserva Ducke, Amazonas, Brazil

    Get PDF
    Herein we describe five new species of the Ectobiidae subfamilies Pseudophyllodromiinae (Amazonina spiculata sp. nov., Amazonina spinostylata sp. nov., Cariblatta duckeniana sp. nov., Cariblatta manauensis sp. nov.) and Nyctiborinae (Nyctibora nigra sp. nov.), collected in the Reserva Ducke, Manaus, state of Amazonas. The specimens were collected from litter, fallen logs, branches, and foliage. We illustrate the male genitalia of the new species

    Heterotic Black Horizons

    Full text link
    We show that the supersymmetric near horizon geometry of heterotic black holes is either an AdS_3 fibration over a 7-dimensional manifold which admits a G_2 structure compatible with a connection with skew-symmetric torsion, or it is a product R^{1,1} * S^8, where S^8 is a holonomy Spin(7) manifold, preserving 2 and 1 supersymmetries respectively. Moreover, we demonstrate that the AdS_3 class of heterotic horizons can preserve 4, 6 and 8 supersymmetries provided that the geometry of the base space is further restricted. Similarly R^{1,1} * S^8 horizons with extended supersymmetry are products of R^{1,1} with special holonomy manifolds. We have also found that the heterotic horizons with 8 supersymmetries are locally isometric to AdS_3 * S^3 * T^4, AdS_3 * S^3 * K_3 or R^{1,1} * T^4 * K_3, where the radii of AdS_3 and S^3 are equal and the dilaton is constant.Comment: 35 pages, latex. Minor alterations to equation (3.11) and section 4.1, the conclusions are not affecte

    Midday measurements of leaf water potential and stomatal conductance are highly correlated with daily water use of Thompson Seedless grapevines

    Get PDF
    A study was conducted to determine the relationship between midday measurements of vine water status and daily water use of grapevines measured with a weighing lysimeter. Water applications to the vines were terminated on August 24th for 9 days and again on September 14th for 22 days. Daily water use of the vines in the lysimeter (ETLYS) was approximately 40 L vine−1 (5.3 mm) prior to turning the pump off, and it decreased to 22.3 L vine−1 by September 2nd. Pre-dawn leaf water potential (ΨPD) and midday Ψl on August 24th were −0.075 and −0.76 MPa, respectively, with midday Ψl decreasing to −1.28 MPa on September 2nd. Leaf g s decreased from ~500 to ~200 mmol m−2 s−1 during the two dry-down periods. Midday measurements of g s and Ψl were significantly correlated with one another (r = 0.96) and both with ETLYS/ETo (r = ~0.9). The decreases in Ψl, g s, and ETLYS/ETo in this study were also a linear function of the decrease in volumetric soil water content. The results indicate that even modest water stress can greatly reduce grapevine water use and that short-term measures of vine water status taken at midday are a reflection of daily grapevine water us

    Access Impediments to Health Care and Social Services Between Anglophone and Francophone African Immigrants Living in Philadelphia with Respect to HIV/AIDS

    Get PDF
    Objectives To describe the social and cultural differences between Anglophone and Francophone African immigrants which define the impediments that Francophone African immigrants face trying to access health and human services in Philadelphia, Pennsylvania. Methods Surveys and personal interviews were administered to participants in social events, community meetings, and health centers. A Chi-squared analysis was used to contrast the communities. Results Francophone Africans demonstrated less acculturation, education, English fluency, and more legal documentation problems, and thus face greater challenges accessing health care. Anglophone Africans had a higher level of acculturation, fewer language problems, and perceived fewer barriers in accessing health care than Francophone Africans. Conclusions Educating new immigrants, through a more culturally sensitive infectious disease treatment and prevention program, is integral to achieving a higher access and utilization rates of available services; especially in recent Francophone immigrants. A larger study is needed to extend the findings to other cities where immigrants with similar backgrounds or acculturation issues reside

    Study design and baseline characteristics of patients on dialysis in the ASCEND-D trial

    Get PDF
    BACKGROUND: The Anemia Studies in chronic kidney disease (CKD): Erythropoiesis via a Novel prolyl hydroxylase inhibitor (PHI) Daprodustat-Dialysis (ASCEND-D) trial will test the hypothesis that daprodustat is non-inferior to comparator epoetin alfa or darbepoetin alfa for two co-primary endpoints: haemoglobin efficacy and cardiovascular safety. METHODS: We report the trial design, key demographic, clinical, and laboratory findings, and baseline therapies of 2964 patients randomised in the open-label (sponsor-blinded) active-controlled, parallel-group, randomised ASCEND-D clinical trial. We also compare baseline characteristics of ASCEND-D patients with patients who are on dialysis (CKD G5D) enrolled in other large cardiovascular outcome trials (CVOTs) and in the most relevant registries. RESULTS: The median age of patients was 58 years, 43% were female; 67% were white and 16% were black. The median haemoglobin at baseline was 10.4 g/dL. Among randomised patients, 89% were receiving haemodialysis and 11% peritoneal dialysis. Among key co-morbidities, 42% reported a history of diabetes mellitus, and 45% a history of cardiovascular disease. Median blood pressure was 134/74 mmHg. The median weekly dose of epoetin was 5751 units. Intravenous and oral iron use was noted in 64% and 11% of patients, respectively. Baseline demographics were similar to patients with CKD G5D enrolled in other CVOTs and renal patient registries. CONCLUSION: ASCEND-D will evaluate the efficacy and safety of daprodustat compared with epoetin alfa or darbepoetin alfa in the treatment of patients with anaemia with CKD G5D
    corecore