6 research outputs found

    Multilayer Coatings for temperature management through glass windows of buildings

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    Infrared (IR) blocking windows are considered to have an important role in reducing the building’s energy consumption by providing better insulation due to their transparency to visible light and ability to block heat. This work reports on visible light transmitting IR filters formed by a metallic layer between transparent conductive oxides (TCO). GZO as TCO and Cu as the metal layer were the focus of this work. Copper‐based low‐emissivity coatings are being considered as an alternative to that of Ag due to their lower cost and durability for heat reflectors. The TCOs were deposited by sputtering and the metallic layer by resistive thermal evaporation. Depending on the TCO required thickness (from 20 to 269 nm), different deposition times and powers were used and their influence on the optical properties studied. Results showed that the GZO (20 nm)/Metal/GZO (20 nm) multilayers obtained a transmittance at 550 nm of about 78.1% and 63.1% and a NIR reflection of 80.1% and 72.7% for the Ag (11 nm) and Cu (5 nm), respectively. The best performance was accomplished with the GZO (20 nm)/Ag (11 nm)/GZO (20 nm) film. CuS or Ag2S nanoparticles have been added to the coatings as an attempt to absorb NIR radiation and achieve IR‐shielding. These have been synthetized by microwave‐assisted synthesis (MW) and Ag2S also via ultrasonic irradiation (UI). Their optical characteristics were obtained before and after deposition on GZO substrates and GZO‐metal structures by electrospray. The optical properties revealed that adding those nanoparticles causes the metal films to lose their IR reflective properties and some visible transmission.As janelas que bloqueiam os infravermelhos (IR) tĂȘm um papel importante na redução do consumo energĂ©tico dos edifĂ­cios, pois proporcionam um melhor isolamento devido Ă  transparĂȘncia Ă  luz visĂ­vel e capacidade de bloquear o calor. Este trabalho relata os filtros IR de transmissĂŁo de luz visĂ­vel formados por uma camada metĂĄlica entre Ăłxidos condutores transparentes (TCO). O foco incidiu no GZO como TCO e Cu como camada metĂĄlica. Os revestimentos de baixa emissividade Ă  base de cobre estĂŁo a ser consi‐ derados uma alternativa aos de Ag devido ao seu menor custo e durabilidade para refletores de calor. Os TCO foram depositados por pulverização catĂłdica e a camada metĂĄlica por evaporação tĂ©rmica resistiva. Dependendo da espessura do TCO pretendida (entre 20 e 269 nm), foram utilizados diferentes tempos e potĂȘncias de deposição e estudada a sua influĂȘncia nas propriedades Ăłpticas. Os resultados mostraram que as multicamadas GZO (20 nm)/Metal/GZO (20 nm) obtiveram uma transmitĂąncia nos 550 nm de cerca de 78.1% e 63.1% e uma reflexĂŁo no NIR de 80.1% e 72.7% para o Ag (11 nm) e Cu (5 nm), respetivamente. O melhor desempenho foi obtido com o filme GZO (20 nm)/Ag (11 nm)/GZO (20 nm). As nanopartĂ­culas CuS ou Ag2S foram adicionadas aos revestimentos como uma tentativa de absorver a radiação NIR e conseguir uma proteção IR. Estas foram obtidos por sĂ­ntese assistida por micro‐ondas (MW) e o Ag2S ainda por irradiação ultrassĂłnica (UI). As suas caracterĂ­sticas Ăłpticas foram obtidas antes e apĂłs as deposiçÔes por electrospray em substratos GZO e estruturas GZO‐metal. No que respeita Ă s propriedades Ăłticas, a adição das nanopartĂ­culas fez com que as pelĂ­culas metĂĄlicas perdessem as suas propriedades refletoras do IR e alguma transmissĂŁo visĂ­vel

    Is diet partly responsible for differences in COVID-19 death rates between and within countries?

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    Correction: Volume: 10 Issue: 1 Article Number: 44 DOI: 10.1186/s13601-020-00351-w Published: OCT 26 2020Reported COVID-19 deaths in Germany are relatively low as compared to many European countries. Among the several explanations proposed, an early and large testing of the population was put forward. Most current debates on COVID-19 focus on the differences among countries, but little attention has been given to regional differences and diet. The low-death rate European countries (e.g. Austria, Baltic States, Czech Republic, Finland, Norway, Poland, Slovakia) have used different quarantine and/or confinement times and methods and none have performed as many early tests as Germany. Among other factors that may be significant are the dietary habits. It seems that some foods largely used in these countries may reduce angiotensin-converting enzyme activity or are anti-oxidants. Among the many possible areas of research, it might be important to understand diet and angiotensin-converting enzyme-2 (ACE2) levels in populations with different COVID-19 death rates since dietary interventions may be of great benefit.Peer reviewe

    Characterisation of microbial attack on archaeological bone

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    As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

    Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

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    © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research

    Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

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    Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P &lt; 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)
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