3,208 research outputs found

    PLA films with improved flexibility properties by using maleinized cottonseed oil

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    [EN] This work assesses the potential of maleinized cottonseed oil MCSO as plasticizer in poly(lactic acid) PLA films with improved ductile behaviour. The effects of MCSO are compared with commercially available maleinized oil, i.e. maleinized linseed oil MLO in terms of mechanical, thermal and barrier properties, as well as morphology changes. Plasticized PLA formulations were obtained with a maleinized oil content in the 0 10 wt% range. Addition of both maleinized vegetable oils leads to a slight decrease in the glass transition temperature (Tg) of neat PLA from 63 °C to 60 61 °C. Nevertheless, MCSO provides better overall properties. Addition of 7.5 wt% MCSO increases the elongation at break by 292%. Regarding the barrier properties, both maleinized vegetable oils increase the oxygen transmission rate OTR. Nevertheless, this increase is less pronounced in the case of MCSO thus indicating its higher efficiency compared to MLO. On the other hand, addition of both maleinized vegetable oils do not compromise the overall disintegration of the obtained PLA formulations, thus positioning these additives as environmentally friendly solutions to increase ductile properties in PLA-based films.This research was supported by the Ministry of Economy and Competitiveness - MINECO, Ref: MAT2014-59242-C2-1-R. Carbonell-Verdu wants to thank Universitat Politecnica de Valencia for financial support through an FPI grant. Garcia-Garcia wants to thanks the Spanish Ministry of Education, Culture and Sports for their financial support through an FPU grant (FPU13/06011).Carbonell-Verdu, A.; Garcia-Garcia, D.; Dominici, F.; Torre, L.; Sanchez-Nacher, L.; Balart, R. (2017). PLA films with improved flexibility properties by using maleinized cottonseed oil. European Polymer Journal. 91:248-259. https://doi.org/10.1016/j.eurpolymj.2017.04.013S2482599

    A 2D ray-tracing based model for wave propagation through forests at micro-and millimeter wave frequencies

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    This paper proposes the extension of a 2-D ray-tracing-based model for radiowave propagation in the presence of trees and vegetation areas to include real-sized trees and outdoor forest scenarios. The original propagation model proved to be suitable to characterize the electromagnetic behavior in the presence of indoor tree formation scenarios, despite some limitations found when applied to real-sized trees. In addition, the original propagation model requires the prior knowledge of the trees’ re-radiation function to extract the relevant propagation input parameters, which is not always possible to obtain in outdoor scenarios. Therefore, an empirical method to extract the relevant input propagation parameters based on simple measurements is proposed. The performance of the proposed propagation model extension is extensively assessed in both the line-of-trees and tree formation scenarios, including various (and mixed) species, both in- and out-of-leaf foliation states, and at three signal frequencies. Finally, depending on the type of scenario, a benchmark between the proposed propagation model and both the radiative energy transfer (RET) and discrete RET (dRET) models, for line-of-trees and tree formation, respectively, is presented.info:eu-repo/semantics/publishedVersio

    Asteroseismic estimate of helium abundance of a solar analog binary system

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    16 Cyg A and B are among the brightest stars observed by Kepler. What makes these stars more interesting is that they are solar analogs. 16 Cyg A and B exhibit solar-like oscillations. In this work we use oscillation frequencies obtained using 2.5 years of Kepler data to determine the current helium abundance of these stars. For this we use the fact that the helium ionization zone leaves a signature on the oscillation frequencies and that this signature can be calibrated to determine the helium abundance of that layer. By calibrating the signature of the helium ionization zone against models of known helium abundance, the helium abundance in the envelope of 16 Cyg A is found to lie in the range 0.231 to 0.251 and that of 16 Cyg B lies in the range 0.218 to 0.266.Comment: Accepted for publication in Ap

    EuroEco (European Health Economic Trial on Home Monitoring in ICD Patients): a provider perspective in five European countries on costs and net financial impact of follow-up with or without remote monitoring

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    Aim: Remote follow-up (FU) of implantable cardiac defibrillators (ICDs) allows for fewer in-office visits in combination with earlier detection of relevant findings. Its implementation requires investment and reorganization of care. Providers (physicians or hospitals) are unsure about the financial impact. The primary end-point of this randomized prospective multicentre health economic trial was the total FU-related cost for providers, comparing Home Monitoring facilitated FU (HM ON) to regular in-office FU (HM OFF) during the first 2 years after ICD implantation. Also the net financial impact on providers (taking national reimbursement into account) and costs from a healthcare payer perspective were evaluated. Methods and results: Atotal of 312 patients with VVI-or DDD-ICD implants from 17 centres in six EU countries were randomised to HMON or OFF, of which 303 were eligible for data analysis. For all contacts (in-office, calendar-or alert-triggered web-based review, discussions, calls) time-expenditure was tracked. Country-specific cost parameters were used to convert resource use into monetary values. Remote FU equipment itself was not included in the cost calculations. Given only two patients from Finland (one in each group) a monetary valuation analysis was not performed for Finland. Average age was 62.4 +/- 13.1 years, 81% were male, 39% received a DDD system, and 51% had a prophylactic ICD. Resource use with HM ON was clearly different: less FU visits (3.79 +/- 1.67 vs. 5.53 +/- 2.32; P < 0.001) despite a small increase of unscheduled visits (0.95 +/- 1.50 vs. 0.62 +/- 1.25; P < 0.005), more non-office-based contacts (1.95+3.29 vs. 1.01 +/- 2.64; P < 0.001), more Internet sessions (11.02 +/- 15.28 vs. 0.06 +/- 0.31; P < 0.001) and more in-clinic discussions (1.84 +/- 4.20 vs. 1.28 +/- 2.92; P < 0.03), but with numerically fewer hospitalizations (0.67 +/- 1.18 vs. 0.85 +/- 1.43, P = 0.23) and shorter length-of-stay (6.31 +/- 15.5 vs. 8.26 +/- 18.6; P = 0.27), although not significant. For the whole study population, the total FU cost for providers was not different for HM ON vs. OFF [mean (95% CI): (sic)204 169-238) vs. (sic)213 (182-243); range for difference ((sic)-36 to 54), NS]. From a payer perspective, FU-related costs were similar while the total cost per patient (including other physician visits, examinations, and hospitalizations) was numerically (but not significantly) lower. There was no difference in the net financial impact on providers [profit of (sic)408 (327-489) vs. (sic)400 (345-455); range for difference ((sic)-104 to 88), NS], but there was heterogeneity among countries, with less profit for providers in the absence of specific remote FU reimbursement (Belgium, Spain, and the Netherlands) and maintained or increased profit in cases where such reimbursement exists (Germany and UK). Quality of life (SF-36) was not different. Conclusion: For all the patients as a whole, FU-related costs for providers are not different for remote FU vs. purely in-office FU, despite reorganized care. However, disparity in the impact on provider budget among different countries illustrates the need for proper reimbursement to ensure effective remote FU implementation

    Spanish study of anticoagulation in haemodialysis

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    This study's objectives were to determine which anticoagulation methods are commonly used in patients who are undergoing haemodialysis (HD) in Spain, on what criteria do they depend, and the consequences arising from their use. MATERIAL AND METHOD: Ours was a cross-sectional study based on two types of surveys: a "HD Centre Survey" and a "Patient Survey". The first survey was answered by 87 adult HD units serving a total of 6093 patients, as well as 2 paediatric units. Among these units, 48.3% were part of the public health system and the remaining 51.7% units were part of the private health system. The patient survey analysed 758 patients who were chosen at random from among the aforementioned 78 HD units. RESULTs: A) HD Centre Survey: The majority of adult HD units (n=61, 70.2%) used both kinds of heparin, 19 of them (21.8%) only used LMWH and 7 of them (8%) only used UFH. The most frequently applied criteria for the use of LMWH were medical indications (83.3% of HD units) and ease of administration (29.5%). The most frequently used methods for adjusting the dosage were clotting of the circuit (88.2% of units), bleeding of the vascular access after disconnection (75.3%), and patient weight (57.6%). B) Patient Survey: The distribution of the types of heparin used was: UFH: 44.1%, LMWH: 51.5%, and dialysis without heparin in 4.4% of patients. LMWH was more frequently used in public medical centres (64.2% of patients) than in private medical centres (46.1%) (P<.001). LMWH was more frequently used in on-line haemodiafiltration (HF) than in high-flux HD (P<.001). Antiplatelet agents were given to 45.5% of patients, oral anticoagulants to 18.4% of patients, and both to 5% of patients. Additionally, 4.4% of patients had suffered bleeding complications during the previous week, and 1.9% of patients suffered thrombotic complications. Bleeding complications were more frequent in patients with oral anticoagulants (P=.001), although there was no association between the type of heparin and the occurrence of bleeding or thrombotic complications. CONCLUSIONS: We are able to conclude that there is a great amount of disparity in the criteria used for the medical prescription of anticoagulation in HD. It is advisable that each HD unit revise their own results as well as those from other centres, and possibly to create an Anticoagulation Guide in Haemodialysis

    Analyzing when parental warmth but without parental strictness leads to more adolescent empathy and self-concept: Evidence from Spanish homes

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    IntroductionClassical research mainly conducted with European-American families has identified the combination of warmth and strictness (authoritative style) as the parenting always associated with the highest scores on developmental outcomes. Additionally, despite the benefits of empathy for prosocial behaviors and protection against antisocial behaviors, most research has considered the contribution of specific practices (e.g., reasoning or power assertion), but not so much the parenting styles. Similarly, family studies tend to study the relationship between parenting and global self-perceptions (self-esteem), but not so much those of each dimension (self-concept).MethodsIn the present study, 600 Spanish adolescents from 12 to 17 years old (M = 15.25, SD = 2.01) were classified within one of the four household typologies (i.e., authoritative, indulgent, authoritarian, or neglectful). Adolescent developmental outcomes were cognitive empathy (adopting perspectives and emotional understanding), emotional empathy (empathic stress and empathic happiness), and self-concept (academic, social, emotional, family and physical).ResultsThe results showed that the indulgent parenting (warmth but not strictness) was related to equal or even better empathy and self-concept than the authoritative style (warmth and strictness), whereas non-warm parenting (authoritarian and neglectful) was consistently associated with poor results.DiscussionOverall, the present findings seriously question that parental strictness combined with parental warmth (authoritative style) is always the parenting style related to the greatest outcomes. By contrast, it seems that reasoning, warmth and involvement, without strictness (indulgent parenting) help adolescents to achieve a good orientation toward others in terms of cognitive and affective empathy and a good self-evaluation in terms of self-concept

    Lesion covariance networks reveal proposed origins and pathways of diffuse gliomas.

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    Diffuse gliomas have been hypothesized to originate from neural stem cells in the subventricular zone and develop along previously healthy brain networks. Here, we evaluated these hypotheses by mapping independent sources of glioma localization and determining their relationships with neurogenic niches, genetic markers and large-scale connectivity networks. By applying independent component analysis to lesion data from 242 adult patients with high- and low-grade glioma, we identified three lesion covariance networks, which reflect clusters of frequent glioma localization. Replicability of the lesion covariance networks was assessed in an independent sample of 168 glioma patients. We related the lesion covariance networks to important clinical variables, including tumour grade and patient survival, as well as genomic information such as molecular genetic subtype and bulk transcriptomic profiles. Finally, we systematically cross-correlated the lesion covariance networks with structural and functional connectivity networks derived from neuroimaging data of over 4000 healthy UK BioBank participants to uncover intrinsic brain networks that may that underlie tumour development. The three lesion covariance networks overlapped with the anterior, posterior and inferior horns of the lateral ventricles respectively, extending into the frontal, parietal and temporal cortices. These locations were independently replicated. The first lesion covariance network, which overlapped with the anterior horn, was associated with low-grade, isocitrate dehydrogenase -mutated/1p19q-codeleted tumours, as well as a neural transcriptomic signature and improved overall survival. Each lesion covariance network significantly coincided with multiple structural and functional connectivity networks, with the first bearing an especially strong relationship with brain connectivity, consistent with its neural transcriptomic profile. Finally, we identified subcortical, periventricular structures with functional connectivity patterns to the cortex that significantly matched each lesion covariance network. In conclusion, we demonstrated replicable patterns of glioma localization with clinical relevance and spatial correspondence with large-scale functional and structural connectivity networks. These results are consistent with prior reports of glioma growth along white matter pathways, as well as evidence for the coordination of glioma stem cell proliferation by neuronal activity. Our findings describe how the locations of gliomas relate to their proposed subventricular origins, suggesting a model wherein periventricular brain connectivity guides tumour development
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