40 research outputs found
Thermally Regenerable Redox Flow Battery for Exploiting Low-Temperature Heat Sources
Harvesting energy from low-temperature heat sources (<100°C) would enable the exploitation of currently untapped renewable sources. Recently proposed techniques fail to reach suitable efficiencies. We propose here a redox flow battery that can be recharged by a thermal process, distillation. The electrochemical cell produces electrical energy from the mixing free energy of two sodium iodide aqueous solutions at different concentrations. The electrochemical cell is based on the technology of sodium ion-conducting ceramics and is coupled with a liquid-liquid extraction process, performed by an unconventional device, the "through-liquid-exchanger." Our technique bypasses the bottleneck of other similar techniques by working with solutions at very high concentrations. Our initial experiments prove an unprecedented energy efficiency (ratio between the electrical work produced and the incoming heat necessary to restore the initial solutions concentrations) of 3% from a heat source <100°C and a power density of 10 W/m2, with the possibility of further improvements. © 2020 The Author(s) The flow battery described by Facchinetti et al. can be recharged by distillation with heat sources <100°C. It enables the efficient exploitation of currently untapped clean and renewable heat sources (e.g., low-concentration solar heat collectors). The design is based on a solid-state ion conductor and includes an unconventional device based on liquid-liquid exchange
Combined Application of X-Ray and Neutron Imaging Techniques to Wood Materials
Conservation of Cultural Heritage is extremely important not only from a cultural point of view, but also from a practical one. It is our duty to pass on to future generations the cultural heritage left tous by our ancestors. Wood is one of the most common materials used to generate works of art which are in a state of constant change and/or deterioration. In order to optimize the knowledge of artworks together with their conservation, it is necessary to use the most advanced scientific and technological tools. In the following paper, we will show the results which can be achieved by application of complementary techniques based on the combined use of X-rays and neutrons as structural probes
New RollâtoâRoll Processable PEDOTâBased Polymer with Colorless Bleached State for Flexible Electrochromic Devices
Conjugated electrochromic (EC) polymers for flexible EC devices (ECDs) generally lack a fully colorless bleached state. A strategy to overcome this drawback is the implementation of a new sidechain-modified poly(3,4-ethylene dioxythiophene) derivative that can be deposited in thin-film form in a customized high-throughput and large-area roll-to-roll polymerization process. The sidechain modification provides enhanced EC properties in terms of visible light transmittance change, ÎÏv = 59% (ÎL* = 54.1), contrast ratio (CR = 15.8), coloration efficiency (η = 530 cmÂČ Câ1), and color neutrality (L* = 83.8, a* = â4.3, b* = â4.1) in the bleached state. The intense blue-colored polymer thin films exhibit high cycle stability (10 000 cycles) and fast response times. The design, synthesis, and polymerization of the modified 3,4-ethylene dioxythiophene derivative are discussed along with a detailed optical, electrochemical, and spectroelectrochemical characterization of the resulting EC thin films. Finally, a flexible see-through ECD with a visible light transmittance change of ÎÏv = 47% (ÎL* = 51.9) and a neutral-colored bleached state is developed
The diacylglycerol kinase α/Atypical PKC/ÎČ1 integrin pathway in SDF-1α mammary carcinoma invasiveness
Diacylglycerol kinase α (DGKα), by phosphorylating diacylglycerol into phosphatidic acid, provides a key signal driving cell migration and matrix invasion. We previously demonstrated that in epithelial cells activation of DGKα activity promotes cytoskeletal remodeling and matrix invasion by recruiting atypical PKC at ruffling sites and by promoting RCP-mediated recycling of α5ÎČ1 integrin to the tip of pseudopods. In here we investigate the signaling pathway by which DGKα mediates SDF-1α-induced matrix invasion of MDA-MB-231 invasive breast carcinoma cells. Indeed we showed that, following SDF-1α stimulation, DGKα is activated and localized at cell protrusion, thus promoting their elongation and mediating SDF-1α induced MMP-9 metalloproteinase secretion and matrix invasion. Phosphatidic acid generated by DGKα promotes localization at cell protrusions of atypical PKCs which play an essential role downstream of DGKα by promoting Rac-mediated protrusion elongation and localized recruitment of ÎČ1 integrin and MMP-9. We finally demonstrate that activation of DGKα, atypical PKCs signaling and ÎČ1 integrin are all essential for MDA-MB-231 invasiveness. These data indicates the existence of a SDF-1α induced DGKα - atypical PKC - ÎČ1 integrin signaling pathway, which is essential for matrix invasion of carcinoma cells
The Tools for Integrated Management of Childhood Illness (TIMCI) study protocol: a multi-country mixed-method evaluation of pulse oximetry and clinical decision support algorithms.
Effective and sustainable strategies are needed to address the burden of preventable deaths among children under-five in resource-constrained settings. The Tools for Integrated Management of Childhood Illness (TIMCI) project aims to support healthcare providers to identify and manage severe illness, whilst promoting resource stewardship, by introducing pulse oximetry and clinical decision support algorithms (CDSAs) to primary care facilities in India, Kenya, Senegal and Tanzania. Health impact is assessed through: a pragmatic parallel group, superiority cluster randomised controlled trial (RCT), with primary care facilities randomly allocated (1:1) in India to pulse oximetry or control, and (1:1:1) in Tanzania to pulse oximetry plus CDSA, pulse oximetry, or control; and through a quasi-experimental pre-post study in Kenya and Senegal. Devices are implemented with guidance and training, mentorship, and community engagement. Sociodemographic and clinical data are collected from caregivers and records of enrolled sick children aged 0-59âmonths at study facilities, with phone follow-up on Day 7 (and Day 28 in the RCT). The primary outcomes assessed for the RCT are severe complications (mortality and secondary hospitalisations) by Day 7 and primary hospitalisations (within 24âhours and with referral); and, for the pre-post study, referrals and antibiotic. Secondary outcomes on other aspects of health status, hypoxaemia, referral, follow-up and antimicrobial prescription are also evaluated. In all countries, embedded mixed-method studies further evaluate the effects of the intervention on care and care processes, implementation, cost and cost-effectiveness. Pilot and baseline studies started mid-2021, RCT and post-intervention mid-2022, with anticipated completion mid-2023 and first results late-2023. Study approval has been granted by all relevant institutional review boards, national and WHO ethical review committees. Findings will be shared with communities, healthcare providers, Ministries of Health and other local, national and international stakeholders to facilitate evidence-based decision-making on scale-up.Study registration: NCT04910750 and NCT05065320
Abdominal drainage after elective colorectal surgery: propensity score-matched retrospective analysis of an Italian cohort
background: In italy, surgeons continue to drain the abdominal cavity in more than 50 per cent of patients after colorectal resection. the aim of this study was to evaluate the impact of abdominal drain placement on early adverse events in patients undergoing elective colorectal surgery. methods: a database was retrospectively analysed through a 1:1 propensity score-matching model including 21 covariates. the primary endpoint was the postoperative duration of stay, and the secondary endpoints were surgical site infections, infectious morbidity rate defined as surgical site infections plus pulmonary infections plus urinary infections, anastomotic leakage, overall morbidity rate, major morbidity rate, reoperation and mortality rates. the results of multiple logistic regression analyses were presented as odds ratios (OR) and 95 per cent c.i. results: a total of 6157 patients were analysed to produce two well-balanced groups of 1802 patients: group (A), no abdominal drain(s) and group (B), abdominal drain(s). group a versus group B showed a significantly lower risk of postoperative duration of stay >6 days (OR 0.60; 95 per cent c.i. 0.51-0.70; P < 0.001). a mean postoperative duration of stay difference of 0.86 days was detected between groups. no difference was recorded between the two groups for all the other endpoints. conclusion: this study confirms that placement of abdominal drain(s) after elective colorectal surgery is associated with a non-clinically significant longer (0.86 days) postoperative duration of stay but has no impact on any other secondary outcomes, confirming that abdominal drains should not be used routinely in colorectal surgery
From Small Metal Clusters to Molecular Nanoarchitectures with a Core-Shell Structure: The Synthesis, Redox Fingerprint, Theoretical Analysis, and Solid-State Structure of [Co38As12(CO)50]4
The cluster [Co38As12(CO)50]4- was obtained by pyrolysis of [Co6As(CO)16]-. The metal cage features a closed-packed core inside a Co/As shell that progressively deforms from a cubic face-centered symmetry. The redox and acid-base reactivities were determined by cyclic voltammetry and spectrophotometric titrations. The calculated electron density revealed the shell-constrained distribution of the atomic charges, induced by the presence of arsenic