Surface plasmon resonance of sparsely dispersed au nanoparticles in TiO2 photoanode of dye sensitised solar cells

Plasmonics is an emerging field that makes use of the nanoscale properties of metals, and its application in solar cells has seen a recent surge of interest [1]. Dye-sensitized solar cells (DSSC) were fabricated by incorporating Au NPs into the TiO2 photoanode. The dye absorption is enhanced by the strong localized electric field from localized surface plasmon and the recombination and back reaction of electrons in DSSC is suppressed by depositing a thin TiO2 blocking layer over the TiO2:Au electrode. An increase in photoresponse was observed in the visible region with TiO2:Au electrode. In particular, we report the observation that a nanoparticles of a noble metal (Au) placed on top of the n-type widegap TiO2 that control the light emission angle can increase the short circuit current density and the quantum efficiency of the cell.FCT (Fundação para a Ciência e Tecnologia) for funding through the Ciencia 2007 programme and the pluriannual contract with CFUM and the European Commission through FP7-PEOPLE-2010-IRSES-NanoCIS (269279

Comparison of the Halpha equivalent width of HII regions in a flocculent and a grand design galaxy: possible evidences for IMF variations

We present here a study of the Halpha equivalent widths of the flocculent galaxy NGC 4395 and the grand design galaxy NGC 5457. A difference between the mean values of the Halpha equivalent widths for the two galaxies has been found. Several hypotheses are presented in order to explain this difference: differences in age, metallicity, star formation rate, photon leakage and initial mass function. Various tests and Monte Carlo models are used to find out the most probable cause of this difference. The resultsshow that the possible cause for the difference could be a variation in the initial mass function. This difference is such that it seems to favor a fraction of more massive stars in the grand design galaxy when compared with the flocculent galaxy. This could be due to a change of the environmental conditions due to a density wave.Comment: 29 pages, 19 figures, accepted for publication in Ap

Tratamiento de fracturas. Cartilla 7

La cartilla describe el concepto de fractura, sus causas, clases de fracturas que se presentan en el ganado, métodos de prevención de fractura, materiales y métodos para tratar fracturas y medidas preventivas para el manejo animalThe primer describes the concept of fracture, its causes, types of fractures that occur in livestock, methods of fracture prevention, materials and methods to treat fractures, and preventive measures for animal handlingConozca las fracturas -- Formas de tratar una fractura -- Cómo alistar el equipo y los materiales – Prepare el animal para el tratamiento -- Tratamiento de las fracturas -- Manera de soltar el animal -- Limpie y guarde el equipo y los materiales27 página

Risk scores for type 2 diabetes mellitus in Latin America : a systematic review of population-based studies

Aim To summarize the evidence on diabetes risk scores for Latin American populations. Methods A systematic review was conducted (CRD42019122306) looking for diagnostic and prognostic models for type 2 diabetes mellitus among randomly selected adults in Latin America. Five databases (LILACS, Scopus, MEDLINE, Embase and Global Health) were searched. type 2 diabetes mellitus was defined using at least one blood biomarker and the reports needed to include information on the development and/or validation of a multivariable regression model. Risk of bias was assessed using the PROBAST guidelines. Results Of the 1500 reports identified, 11 were studied in detail and five were included in the qualitative analysis. Two reports were from Mexico, two from Peru and one from Brazil. The number of diabetes cases varied from 48 to 207 in the derivations models, and between 29 and 582 in the validation models. The most common predictors were age, waist circumference and family history of diabetes, and only one study used oral glucose tolerance test as the outcome. The discrimination performance across studies was similar to 70% (range: 66-72%) as per the area under the receiving-operator curve, the highest metric was always the negative predictive value. Sensitivity was always higher than specificity. Conclusion There is no evidence to support the use of one risk score throughout Latin America. The development, validation and implementation of risk scores should be a research and public health priority in Latin America to improve type 2 diabetes mellitus screening and prevention.Peer reviewe

Defining the Behavior of IoT Devices through the MUD Standard: Review, Challenges, and Research Directions

With the strong development of the Internet of Things (IoT), the definition of IoT devices' intended behavior is key for an effective detection of potential cybersecurity attacks and threats in an increasingly connected environment. In 2019, the Manufacturer Usage Description (MUD) was standardized within the IETF as a data model and architecture for defining, obtaining and deploying MUD files, which describe the network behavioral profiles of IoT devices. While it has attracted a strong interest from academia, industry, and Standards Developing Organizations (SDOs), MUD is not yet widely deployed in real-world scenarios. In this work, we analyze the current research landscape around this standard, and describe some of the main challenges to be considered in the coming years to foster its adoption and deployment. Based on the literature analysis and our own experience in this area, we further describe potential research directions exploiting the MUD standard to encourage the development of secure IoT-enabled scenarios

Diatoms from the Spring Ecosystems Selected for the Long-Term Monitoring of Climate-Change Effects in the Berchtesgaden National Park (Germany)

We studied diatoms from the fifteen springs selected in the Berchtesgaden National Park on behalf of the Bavarian State Ministry for the Environment to be sentinel environments of climate-change effects. For three of these springs, diatom data based on samples taken in 1997 were also available. A total of 162 species belonging to 49 genera were found sampling three microhabitat types (lithic materials, bryophytes, surface sediments). The cumulative percentage of all species included in a threat category including endangered species was 43%, confirming previous findings for comparable environments of the Alps. We could find a statistically significant positive association between the Meinzer variability index for discharge and the cumulative relative abundance of aerial diatom species. This study thus highlighted once again the relevance of discharge (and associated water-level) variability as an environmental determinant of diatom assemblages in spring ecosystems. Increased nitrate concentrations in some springs, likely due to diffuse airborne pollution and, locally, to impacts such as forest management, game, and cattle, led to a relevant occurrence of eutraphentic diatom species. Our results show a segregation of the older data in non-parametric diatom-based ordinations, suggesting a strong potential for the use of spring diatoms in studies aiming at tracking the effects of climate and environmental change

Is it still worth searching for lepton flavor violation in rare kaon decays?

Prospective searches for lepton flavor violation (LFV) in rare kaon decays at the existing and future intermediate-energy accelerators are considered. The proposed studies are complementary to LFV searches in muon-decay experiments and offer a unique opportunity to probe models with approximately conserved fermion-generation quantum number with sensitivity superior to that in other processes. Consequently, new searches for LFV in kaon decays are an important and independent part of the general program of searches for lepton flavor violation in the final states with charged leptons.Comment: 30 pages, 10 figures. An extended version of the talk given at the Chicago Flavor Seminar, February 27, 2004. In the new version some misprints were corrected and some new data for LFV-processes were added. The main content of the paper was not changed. The paper is published in Yad. Fiz. 68, 1272 (2005

Research challenges in nextgen service orchestration

Fog/edge computing, function as a service, and programmable infrastructures, like software-defined networking or network function virtualisation, are becoming ubiquitously used in modern Information Technology infrastructures. These technologies change the characteristics and capabilities of the underlying computational substrate where services run (e.g. higher volatility, scarcer computational power, or programmability). As a consequence, the nature of the services that can be run on them changes too (smaller codebases, more fragmented state, etc.). These changes bring new requirements for service orchestrators, which need to evolve so as to support new scenarios where a close interaction between service and infrastructure becomes essential to deliver a seamless user experience. Here, we present the challenges brought forward by this new breed of technologies and where current orchestration techniques stand with regards to the new challenges. We also present a set of promising technologies that can help tame this brave new world

Dopant-dependent impact of Mn-site doping on the critical-state manganites: R0.6Sr0.4MnO3 (R=La, Nd, Sm, and Gd)

Versatile features of impurity doping effects on perovskite manganites, $R_{0.6}$Sr$_{0.4}$MnO$_{3}$, have been investigated with varying the doing species as well as the $R$-dependent one-electron bandwidth. In ferromagnetic-metallic manganites ($R$=La, Nd, and Sm), a few percent of Fe substitution dramatically decreases the ferromagnetic transition temperature, leading to a spin glass insulating state with short-range charge-orbital correlation. For each $R$ species, the phase diagram as a function of Fe concentration is closely similar to that for $R_{0.6}$Sr$_{0.4}$MnO$_{3}$ obtained by decreasing the ionic radius of $R$ site, indicating that Fe doping in the phase-competing region weakens the ferromagnetic double-exchange interaction, relatively to the charge-orbital ordering instability. We have also found a contrastive impact of Cr (or Ru) doping on a spin-glass insulating manganite ($R$=Gd). There, the impurity-induced ferromagnetic magnetization is observed at low temperatures as a consequence of the collapse of the inherent short-range charge-orbital ordering, while Fe doping plays only a minor role. The observed opposite nature of impurity doping may be attributed to the difference in magnitude of the antiferromagnetic interaction between the doped ions.Comment: 7 pages, 6 figure

Defining the Behavior of IoT Devices through the MUD Standard : Review, Challenges, and Research Directions

With the strong development of the Internet of Things (IoT), the definition of IoT devices' intended behavior is key for an effective detection of potential cybersecurity attacks and threats in an increasingly connected environment. In 2019, the Manufacturer Usage Description (MUD) was standardized within the IETF as a data model and architecture for defining, obtaining and deploying MUD files, which describe the network behavioral profiles of IoT devices. While it has attracted a strong interest from academia, industry, and Standards Developing Organizations (SDOs), MUD is not yet widely deployed in real-world scenarios. In this work, we analyze the current research landscape around this standard, and describe some of the main challenges to be considered in the coming years to foster its adoption and deployment. Based on the literature analysis and our own experience in this area, we further describe potential research directions exploiting the MUD standard to encourage the development of secure IoT-enabled scenarios