Optical characterization of CsCu2I3 and Cs3Cu2I5 metal halide perovskites

Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2022, Tutor: Sergi Hernández MárquezTernary copper halide compounds, where copper presents oxidation state +1 (Cu+), have been of great interest because of their optoelectronic properties. In particular, cesium copper halide nanostructures with composition either CsCu2I3 or Cs3Cu2I5 are materials with excellent emission properties within the visible range, driven by self-trap exciton mechanism. In this work we study the optical properties of two copper based halide perovskites, CsCu2I3 and Cs3Cu2I5, first at room temperature and later with dependence on temperature. We found that the excitation of the PLE is occurring in the UV region, in agreement with the absorption edge. As a function of the temperature, the band gap decreases with the temperature for both composition, however the emission behaviour exhibits an apparent anomalous behaviour with temperature. The results are discussed in terms of the excitation energy and the bandgap dependence with temperatur

Simulation for fiber optics pulse propagation through a numerical solution of the Nonlinear Schrödinger Equation

Fiber pulse propagation is a common scenario in optical experiments. This article is a numerical simulation of such propagation using the split-step Fourier method with a brief discussion on its effects. To conclude, simulations with optical solitons are made since their special behaviour serve as a way to validate the numerical calculations.2019/202

Working with laboratory rodents in Spain: a survey on welfare and wellbeing

[EN] Background: Replacement, reduction and refinement, the 3R principles, provide a framework to minimize the use and suffering of animals in science. In this context, we aimed to determine the actual perception that individuals working with laboratory rodents in biomedical research have on animal welfare and on their interaction with the animals, as well as how they perceive its impact on their social relations. To this end, we designed an anonymous on-line survey for people working with rodents, at three responsibility levels, in Spain. Results: Of the 356 participants, 239 were women (67 %); 263 were researchers (74%), and 93 animal facility staff (26%), of which 55 were caretakers/technicians (15 %), and 38 welfare officer/veterinarians (11 %). Animal facility staff indicated environmental enrichment to be a universal practice. About half of the participants reported that, in their opinion, animals suffer “little to none” or “minor” stress and pain. Animal caretakers/technicians and researchers perceived higher levels of stress and pain than welfare officers/veterinarians. Participants judged decapitation the most unpleasant method to kill rodents, whereas anaesthetic overdose was the least one. A sizable proportion − 21% of animal caretakers/technicians and 11.4% of researchers - stated that they were never given the choice not to euthanize the rodents they work with. Overall, women reported higher interactions with animals than men. Nevertheless, we could detect a significant correlation between time spent with the animals and interaction scores. Notably, 80% of animal facility staff and 92% of researchers rarely talked about their work with laboratory rodents with people outside their inner social circle. Conclusions: Overall, the participants showed high awareness and sensitivity to rodent wellbeing; animal facility staff reported a similar perception on welfare questions, independently of their category, while researchers, who spent less time with the animals, showed less awareness and manifested lower human-animal interaction and less social support. Regarding the perception on social acceptance of laboratory animal work, all groups were cautious and rarely talked about their job, suggesting that it is considered a sensitive issue in Spain.The research of G.A. is supported by grants from University of Basque Country (UPV/EHU) - Psicobiologia PPGI19/14 and GIU18/103

A survey on the use of mice, pigs, dogs and monkeys as animal models in biomedical research in Spain

[EN] Background The use of animals in biomedical science remains controversial. An individual's level of concern is generally influenced by their culture, previous or current experience with animals, and the specific animal species in question. In this study we aimed to explore what people in Spain who had never or who no longer worked with laboratory animals thought of the use of mice, pigs, dogs and monkeys for biomedical research purposes. We also aimed to determine whether or not people currently involved in biomedical research with the aforementioned species felt their work was justified. Results The study comprised a total of 807 participants (never worked = 285, used to work = 56, currently working = 466), almost two thirds of whom were women. Our results revealed that the phylogenetic scale is an important factor in people's opinions of the use of certain species in research. The percentage of people who were against the use of dogs or monkeys was higher than that of those who were against the use of mice or pigs. The main reasons given for having stopped working with laboratory animals were change of professional career and change in research project. Participants who were currently working with animals believed that their work was justified, but said they did not talk about it with people outside their immediate social circle. Conclusions Our findings suggest that there is a difference in moral status between monkeys and mice, as well as between companion animals (dogs) and farm animals (pigs). Our results support the idea that working with laboratory animals is a sensitive issue in Spain.The research of G.A. is supported by Grants from University of Basque Country (UPV/EHU)-Psicobiologia PPGI19/14

Mapping direct N2O emissions from peri-urban agriculture : the case of the Metropolitan Area of Barcelona

Unidad de excelencia María de Maeztu CEX2019-000940-MAltres ajuts: acords transformatius de la UABGeographically explicit datasets reflecting local management of crops are needed to help improve direct nitrous oxide (N2O) emission inventories. Yet, the lack of geographically explicit datasets of relevant factors influencing the emissions make it difficult to estimate them in such way. Particularly, for local peri-urban agriculture, spatially explicit datasets of crop type, fertilizer use, irrigation, and emission factors (EFs) are hard to find, yet necessary for evaluating and promoting urban self-sufficiency, resilience, and circularity. We spatially distribute these factors for the peri-urban agriculture in the Metropolitan Area of Barcelona (AMB) and create N2O emissions maps using crop-specific EFs as well as Tier 1 IPCC EFs for comparison. Further, the role of the soil types is qualitatively assessed. When compared to Tier 1 IPCC EFs, we find 15% more emissions (i.e. 7718 kg N2O-N year−1) than those estimated with the crop-specific EFs (i.e. 6533 kg N2O-N year−1) for the entire AMB. Emissions for most rainfed crop areas like cereals (e.g. oat and barley) and non-citric fruits (e.g. cherries and peaches), which cover 24% and 13% of AMB's peri-urban agricultural area respectively, are higher with Tier 1 EF. Conversely, crop-specific EFs estimate higher emissions for irrigated horticultural crops (e.g. tomato, artichoke) which cover 33% of AMB's peri-urban agricultural area and make up 70% of the total N2O emissions (4588 kg N2O-N year−1 using crop-specific EFs). Mapping the emissions helps evaluate spatial variability of key factors such as fertilizer use and irrigation of crops but carry uncertainties due to downscaling regional data to represent urban level data gaps. It also highlighted core emitting areas. Further the usefulness of the outputs on mitigation, sustainability and circularity studies are briefly discussed

Professional Quality of Life in Research Involving Laboratory Animals

Many workers contribute to the success of animal welfare and study outcomes in biomedical research. However, the professional quality of life (ProQoL) of those who work with laboratory animals has not been explored in Spain. To this end, we adapted the ProQoL scale to the Spanish population working with laboratory animals. Participants were contacted by email and asked to complete an anonymous on-line questionnaire. The study comprised a total of 498 participants, 12.4% welfare officers/veterinarians, 19.5% caretaker/technicians, 13.9% principal investigators, 20.7% investigators, 13.6% research technicians, and 19.9% PhD students. The adapted scale revealed very good reliability and internal validity, providing information about two different subscales, compassion satisfaction and compassion fatigue. Animal-facility personnel showed higher total ProQoL and compassion-satisfaction scores than researchers; PhD students showed the lowest scores. Thus, our results indicate that job category is a contributing factor in perceived professional quality of life. We observed that compassion satisfaction is negatively associated with the perceived animal stress/pain. Participants reporting poorer compassion satisfaction also reported lower social-support scores. Overall, our ProQoL scale is a useful tool for analyzing the professional quality of life in the Spanish population, and may help to design future interventions to improve workplace wellbeing in Spain and other Spanish-speaking populations.The research of G.A. is supported by grants from the University of Basque Country (UPV/EHU)—Psicobiologia PPGI19/14 and GIU18/103

SARS-CoV-2 Contacts’ Symptom Development and Secondary Attack Rate: A Retrospective Analysis of a Contact-Tracing Cohort in Catalonia

Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Rastreig de contactes; Taxa d'atac secundari; QuarantenaCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Rastreo de contactos; Tasa de ataque secundario; CuarentenaCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Contact tracing; Secondary attack rate; QuarantineContact tracing outcome indicators, such as symptom development (SD) and secondary attack rate (SAR) among close contacts (CCs), are key to understanding SARS-CoV-2 transmission. This study analyses SD and SAR and estimates the incubation period (IP) from a cohort of 47,729 CCs from 17,679 SARS-CoV-2 cases diagnosed in Catalonia (Spain) from May to August 2020. Globally, 19.4% of the CCs reported symptoms, especially adult women living in urban areas. SAR was 24.5%, notably higher among infants (37.6%), and 45.9% of secondary cases (SCs) were asymptomatic. Household CCs had 98% (OR: 1.98, 95% CI: 1.81–2.18) and 138% (2.38, 2.19–2.58) increased risk of SD and becoming SCs compared to social settings. The IP was 3.42 days, being 4.10 days among social CCs, and only 15.4% and 4.8% of SCs developed symptoms after days 7 and 10 of quarantine, respectively. These results, notably the higher SAR among asymptomatic children, highlight the importance of diligent monitoring to inform SARS-CoV-2 control strategies

SARS-CoV-2 Catalonia contact tracing program: evaluation of key performance indicators

Coronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Rastreig de contactes; Indicador clau de rendiment; Avaluació del programaCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Rastreo de contactos; Indicador clave de rendimiento; Evaluación del programaCoronavirus SARS-CoV-2; COVID-19; 2019-nCoV; Contact tracing; Key performance indicator; Program evaluationBackground: Guidance on SARS-CoV-2 contact tracing indicators have been recently revised by international public health agencies. The aim of the study is to describe and analyse contact tracing indicators based on Catalonia’s (Spain) real data and proposing to update them according to recommendations. Methods: Retrospective cohort analysis including Catalonia’s contact tracing dataset from 20 May until 31 December 2020. Descriptive statistics are performed including sociodemographic stratification by age, and differences are assessed over the study period. Results: We analysed 923,072 contacts from 301,522 SARS-CoV-2 cases with identified contacts (67.1% contact tracing coverage). The average number of contacts per case was 4.6 (median 3, range 1–243). A total of 403,377 contacts accepted follow-up through three phone calls over a 14-day quarantine period (84.5% of contacts requiring follow-up). The percentage of new cases declared as contacts 14 days prior to diagnosis evolved from 33.9% in May to 57.9% in November. All indicators significantly improved towards the target over time (p < 0.05 for all four indicators). Conclusions: Catalonia’s SARS-CoV-2 contact tracing indicators improved over time despite challenging context. The critical revision of the indicator’s framework aims to provide essential information in control policies, new indicators proposed will improve system delay’s follow-up. The study provides information on COVID-19 indicators framework experience from country’s real data, allowing to improve monitoring tools in 2021–2022. With the SARS-CoV-2 pandemic being so harmful to health systems and globally, is important to analyse and share contact tracing data with the scientific community

Perforated polyester nanomebranes as templates of electroactive and robust free-standing films

Robust and flexible free-standing films made of spin-coated poly(lactic acid) (PLA) and poly(3,4-ethylenedioxythiophene) (PEDOT) nanolayers have been prepared. A steel sheet coated with a sacrificial layer of PEDOT:poly(styrenesulfonate) (PSS) and a spin-coated nanolayer of PLA was used as working electrode for the anodic polymerization of 3,4-ethylenedioxythiophene monomer. The latter was only successfully accomplished when rounded-shape nanoperforations of average diameter 49¿±¿14¿nm were introduced into PLA layers, which was achieved by combining the phase segregation processes undergone by immiscible PLA:poly(vinyl alcohol) (PVA) mixtures with selective solvent etching to remove PVA domains. Nanoperforations allowed the utilization of the semiconducting PEDOT:PSS sacrificial layer to immobilize the electropolymerized PEDOT chains. Morphological and topographical studies show the templating effect of PEDOT layers. In addition of flexibility and mechanical strength, free-standing 5-layered films present good electrochemical activity, evidencing their potential ability to reversibly exchange ions with the medium. These properties offer important advantages with respect to those of neat PLA and supported PEDOT films, as has been illustrated by cell culture and protein adsorption assays. Cell cultures evidenced the superior behavior of 5-layered films as bioactive platforms for fibroblast and epithelial cells proliferation, while adsorption assays reflected their potential as selective bioadhesive surfaces for protein separationPeer ReviewedPostprint (author's final draft

Crystallographic information data of natural occurring zaccariniite (RhNiAs) obtained by means of precession electron diffraction

The crystal structure of naturally occurring zaccariniite (RhNiAs) has been studied in Transmission Electron Microscopy (TEM) with variable angle Precession Electron Diffraction (PED) techniques. The analysis of the data has yielded tetragonal cell parameters of 3.86, 3.86, 6.77 Å and space group of P4/nmm for the basic structure, and its constituent atom positions for Ni, As and Rh were determined as well by ab-initio structure resolution method. The data is related to "Structural characterization and ab-initio resolution of natural occurring zaccariniite (RhNiAs) by means of Precession Electron Diffraction" (Roqué Rosell et al., 2019)