240 research outputs found

    Multiferroicity in V-doped PbTiO3_{3}

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    We report \emph{ab initio} predictions on the proper multiferroic (ferromagnetic, insulating and ferroelectric) character of PbTiO3_{3} doped with vanadium. V impurities coupled ferromagnetically carry a magnetization of 1 μB\mu_{\rm B} each. The coupling is expected to be strong, since the paramagnetic solution is higher by 150 meV/vanadium, and no stable antiferromagnetic solution was found. The electronic gap in the doped system is about 0.2-0.3 eV in GGA, hence the system is properly multiferroic. V doping increases the spontaneous polarization in PbTiO3_{3}, with an approximate percentual rate of 0.7 μ\muC/cm2^{2}.Comment: 4 pages, 3 figures, 1 tabl

    Giant electroresistance and tunable magnetoelectricity in a multiferroic junction

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    First-principles density functional calculations show that the SrRuO3/PbTiO3/SrRuO3\textrm{SrRuO}_{3}/\textrm{PbTiO}_{3}/\textrm{SrRuO}_{3} multiferroic junction with asymmetric (RuO2_{2}/PbO and TiO2_{2}/SrO) interfaces has a large ferroelectric depolarizing field, whose switching changes the interface transmission probabilities for tunneling electrons, leading to electroresistance modulation over several orders of magnitude. The switching further affects the interface spin density, naturally driving magnetoresistance as well as modulated spin-dependent in-plane resistivity, which may be exploited in field-effect devices.Comment: 7 pages, 10 figures, 1 table; extended upon revie

    Low In solubility and band offsets in the small-xx β\beta-Ga2_2O3_3/(Ga1x_{1-x}Inx_x)2_2O3_3 system

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    Based on first-principles calculations, we show that the maximum reachable concentration xx in the (Ga1x_{1-x}Inx_x)2_2O3_3 alloy in the low-xx regime (i.e. In solubility in β\beta-Ga2_2O3_3) is around 10%. We then calculate the band alignment at the (100) interface between β\beta-Ga2_2O3_3 and (Ga1x_{1-x}Inx_x)2_2O3_3 at 12%, the nearest computationally treatable concentration. The alignment is strongly strain-dependent: it is of type-B staggered when the alloy is epitaxial on Ga2_2O3_3, and type-A straddling in a free-standing superlattice. Our results suggest a limited range of applicability of low-In-content GaInO alloys.Comment: 3 pages, 3 figure

    Kratkotrajni učinci izloženosti niskim koncentracijama didušikova oksida u anesteziologa

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    The aim of this study was to assess whether a sample of 37 anaesthetists occupationally exposed only to N2O showed any deterioration in vigilance and/or mood. The anaesthetists were examined with three neurobehavioural tests (Simple Reaction Time and Colour Word Vigilance to measure the vigilance and Mood Rating Scale to evaluate the level of stress and arousal) and underwent N2O biological monitoring (to correlate the test results with the N2O exposure) on the first and on the last day of the work week, before and after work in the operating room. No significant relationship was found between the biological monitoring and the test results. The only significant statistical difference was found between the beginning and the end of each workday in the arousal level, regardless of the result of the biological monitoring.Cilj je ovoga ispitivanja bio utvrditi do kakvih promjena budnosti i raspoloženja dolazi u 37 anesteziologa profesionalno izloženih didušikovu oksidu. Promjene u budnosti ispitane su s pomoću zadatka jednostavnog vremena reagiranja i zadatka pozornosti, a promjene u raspoloženju s pomoću skale procjene različitih raspoloženja. Mjerenja su izvršena na početku i na kraju prvog i zadnjeg radnog dana u tjednu, a mjerenja didušikova oksida u urinu izvršena su samo na kraju radnog vremena prvoga i posljednjeg radnog dana u tjednu. Nije utvrđena povezanost između rezultata biološkog monitoringa i psihologijskog ispitivanja. Konzistentne statistički značajne razlike utvrđene su jedino u subjektivnim procjenama budnosti na početku i na kraju radnog dana

    Standardising policy and technology responses in the immediate aftermath of a pandemic: a comparative and conceptual framework

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    Background: The initial policy response to the COVID-19 pandemic has differed widely across countries. Such variability in government interventions has made it difficult for policymakers and health research systems to compare what has happened and the effectiveness of interventions across nations. Timely information and analysis are crucial to addressing the lag between the pandemic and government responses to implement targeted interventions to alleviate the impact of the pandemic. Methods: To examine the effect government interventions and technological responses have on epidemiological and economic outcomes, this policy paper proposes a conceptual framework that provides a qualitative taxonomy of government policy directives implemented in the immediate aftermath of a pandemic announcement and before vaccines are implementable. This framework assigns a gradient indicating the intensity and extent of the policy measures and applies the gradient to four countries that share similar institutional features but different COVID-19 experiences: Italy, New Zealand, the United Kingdom and the United States of America. Results: Using the categorisation framework allows qualitative information to be presented, and more specifically the gradient can show the dynamic impact of policy interventions on specific outcomes. We have observed that the policy categorisation described here can be used by decision-makers to examine the impacts of major viral outbreaks such as SARS-CoV-2 on health and economic outcomes over time. The framework allows for a visualisation of the frequency and comparison of dominant policies and provides a conceptual tool to assess how dominant interventions (and innovations) affect different sets of health and non-health related outcomes during the response phase to the pandemic. Conclusions: Policymakers and health researchers should converge toward an optimal set of policy interventions to minimize the costs of the pandemic (i.e., health and economic), and facilitate coordination across governance levels before effective vaccines are produced. The proposed framework provides a useful tool to direct health research system resources and build a policy benchmark for future viral outbreaks where vaccines are not readily available

    Bridging Terrestrial and Marine Geoheritage: Assessing Geosites in Porto\ufb01no Natural Park (Italy)

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    Interest in geoheritage research has grown over the past 25years and several countries have issued laws to encourage improvement and conservation. Investigations on geosites are prevalently carried out on land environments, although the study of underwater marine environments is also of paramount scienti\ufb01c importance. Nevertheless, due to the constraints of underwater environments, these sites have been little explored, also on account of the higher costs and di\ufb03culties of surveying. This research has identi\ufb01ed and assessed the terrestrial and marine geosites of the Porto\ufb01no Natural Park and Protected Marine Area, which are internationally famous owing to both the land scenic features and the quality of the marine ecosystem. The goal was to pinpoint the most suitable sites for tourist improvement and fruition and identify possible connections between the two environments. Inall,28 terrestrial sites and 27 marine sites have been identi\ufb01ed and their scienti\ufb01c value as well as their ecological, cultural, and aesthetic importance has been assessed. In addition, accessibility, services, and economic potential of geosites has also been taken into account. Both the updated database of terrestrial and marine geo sites in the Porto\ufb01no protected areas and the assessment procedure adopted can become useful tools for the managers of these sites and provide decision-makers with possible strategies for tourist development

    Response on Yield and Nutritive Value of Two Commercial Maize Hybrids as a Consequence of a Water Irrigation Reduction

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    The present study investigated in a practical farm condition the response of two commercial maize hybrids (maturity class FAO rating 700) grown for silage production on chemical composition and digestibility of whole maize plant as consequence of a severe water irrigation reduction. Based on different irrigation applications, water restricted (WR) and fully irrigated (FI) plots received 50 and 200 mm of irrigation water, respectively. A split-plot factorial arrangement in a randomised complete block design with two main plots (WR and FI) and two sub-plots (hybrid A and B) with 12 replications/ treatment was performed. Studied parameters were dry matter (DM) yield, harvest index (HI), chemical composition, rumen in situ DM and neutral detergent fibre disappearance (DMD and NDFD, respectively), indigestible NDF (iNDF), 7h in vitro starch degradability (7hIVSD) and net energy (NE) for lactation content. Total DM and grain yields, HI and chemical composition differed (P<0.05) between FI and WR crops and only slight differences were recorded between hybrids. When compared to FI plants, WR had lower starch and higher fibre contents (P<0.05). Higher DMD (59.2 vs 56.4% DM) and NDFD (61.0 vs 58.4% NDFOM) were measured for FI with respect to WR crops, whereas iNDF was about 36% higher (P<0.05) in WR than FI. Lastly, WR plants had a lower NE content than FI plants (P<0.05). Our research showed that a drastic reduction in water irrigation negatively affected whole plant yield, chemical composition and nutrient availability of forage maize

    Palliation with a multimodality treatment including hypoxic pelvic perfusion for unresectable recurrent rectal cancer: outcomes based on a retrospective study

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    Patients with unresectable recurrent rectal cancer that progresses after systemic chemotherapy and radiotherapy are candidates for palliation with hypoxic pelvic perfusion (HPP). The aim of this observational retrospective study was to evaluate if a multimodality treatment including HPP and targeted-therapy may be useful to prolong clinical responses and survival of these patients. From a cohort of 77 patients with unresectable recurrent rectal cancer in progression after standard treatments and submitted to HPP, 21 patients underwent repeat HPP using mitomycin C (MMC) at the dose of 25&nbsp;mg/m2. After the last HPP, 7 patients received a targeted-therapy with cetuximab according to overexpression of epidermal growth factor receptor in recurrence cancer cells. The median overall survival of these 21 patients from the diagnosis of unresectable recurrent rectal cancer was 23&nbsp;months (iqr 18-24). After the first HPP, the median survival of the 21 patients until death or end of follow-up was 10&nbsp;months (iqr 9-13). The 1-year and 2-year survival rates were 71.4%, and 4.8%, respectively. From the first HPP, age\u2009&gt;\u200960&nbsp;years, a recurrence shrinkage of at least 30% (partial response), and the addition of a post-HPP targeted-therapy with cetuximab significantly affected survival (P\u2009&lt;\u20090.04). In conclusion, repeated MMC-HPP followed by targeted-therapy seems to be an effective palliative treatment for patients with unresectable recurrent rectal cancer in progression after systemic chemotherapy and radiation but the results of this study have to be confirmed by a larger phase III trial
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