Kommerell's diverticulum and right-sided aortic arch: a cohort study and review of the literature

AbstractWe report four consecutive cases of Kommerell's aneurysm of an aberrant left subclavian artery in patients with a right-sided aortic arch and the results of a systematic review of the literature. In our cohort of patients, three had an aneurysm limited to the origin of the aberrant subclavian artery, causing dysphagia and cough, and one had an aneurysm involving also the distal arch and the entire descending thoracic aorta, causing compression of the right main-stem bronchus. A left subclavian-to-carotid transposition was performed in association with the intrathoracic procedure, and a right thoracotomy was used in all patients. One of the patients underwent surgery with deep hypothermia and circulatory arrest, and the others with the adjunct of a left-heart bypass. The repair was accomplished with an interposition graft in two patients and with endoaneurysmorrhaphy in the others. The postoperative course was complicated by respiratory failure and prolonged ventilation in one patient, and one patient died because of severe pulmonary emboli. The survivors are alive and well at a follow-up of 1 to 3 years. Only 32 cases of right-sided aortic arch with an aneurysm of the aberrant subclavian artery have been reported: 12 were associated with aortic dissection, and 2 presented with rupture. Surgical repair was accomplished in 29 patients. A number of operative strategies were described: right thoracotomy, bilateral thoracotomy, left thoracotomy with sternotomy, sternotomy with right thoracotomy, and left thoracotomy. In only 12 cases was the subclavian artery reconstructed. We believe that a right thoracotomy provides good exposure and avoids the morbidity associated with bilateral thoracotomy or sternotomy and thoracotomy. We feel that a left subclavian-to-carotid transposition completed before the thoracic approach revascularizes the subclavian distribution without increasing the complexity of the intrathoracic procedure

In situ observation of heat-induced degradation of perovskite solar cells

The lack of thermal stability of perovskite solar cells is hindering the progress of this technology towards adoption in the consumer market. Different pathways of thermal degradation are activated at different temperatures in these complex nanostructured hybrid composites. Thus, it is essential to explore the thermal response of the mesosuperstructured composite device to engineer materials and operating protocols. Here we produce devices according to four well-established recipes, and characterize their photovoltaic performance as they are heated within the operational range. The devices are analysed using transmission electron microscopy as they are further heated in situ, to monitor changes in morphology and chemical composition. We identify mechanisms for structural and chemical changes, such as iodine and lead migration, which appear to be correlated to the synthesis conditions. In particular, we identify a correlation between exposure of the perovskite layer to air during processing and elemental diffusion during thermal treatment. Solar cells based on lead halide perovskite composites have become increasingly popular in the past few years owing to a combination of low synthesis cost and high power conversion efficiency, with certified values in excess of 20% (refs 1,2,3,4,5). However, the stability of such devices is a concern—it is well known that heating at or above around 85 ∘C, a temperature close to those reached during normal operation in full sunlight, performance degrades rapidly, and such instability is exacerbated by exposure to moisture; systematic thermal and ageing studies are required to understand such degradation processes. Changes happen in both the organic and inorganic components of the cells; the resilience of the perovskite layer, in particular, is expected to become a limiting factor once different hole-conducting materials (or hole-conductor-free cells) are developed. To overcome this limitation, it is vital to understand the degradation pathways of the structures involved, which here are observed at nanometre-scale spatial resolution in situ, inside an analytical scanning transmission electron microscope (STEM), while the composition is monitored with elemental mapping through energy-dispersive X-ray analysis (EDX). The analysis of such devices is challenging owing to several factors. The spatial dimensions relevant to the fabrication and the operation of the cells are in the 1–100 nm range, and the materials are easily damaged by exposure to an electron beam in a TEM, requiring careful tuning of the electron dose. The system also includes organic and inorganic components in an assembly with complex chemistry and morphology. Finally, the rapid changes to the devices in air and the low degradation temperatures pose an additional challenge to the experiment, which needs to be timed appropriately and carefully executed. The monitoring of this process is made possible by combining several recent advances in TEM technology. The use of high-brightness electron guns and detectors with large collection areas allows the fast acquisition of high-quality EDX maps with limited electron dose on the sample; the signal-to-noise ratio of the maps can be further increased by applying denoising algorithms (PCA, principal components analysis) within an open-source software suite. The development of novel in situ heating holders for TEM, based on micro-heaters and featuring high stability and fast response, was also crucial—in particular, the holder used here allows very precise control (sub-degree) at values just above room temperature, as well as providing fast heating and cooling (a few seconds for the temperatures in use in this paper). The good spatial stability of the holder is crucial in acquiring EDX maps.G.D., S.C., and C.D. acknowledge funding from ERC under grant number 259619 PHOTO EM. C.D. acknowledges financial support from the EU under grant number 312483 ESTEEM2. F.M., L.C. and A.D.C. acknowledge funding from “Polo Solare Organico” Regione Lazio, the “DSSCX” MIURPRIN2010 and FP7 ITN “Destiny”. G.D and S.C. thank Dr. Francisco de la Peña and Dr. Pierre Burdet for assistance with PCA analysis.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nenergy.2015.1

I paesaggi delle industrie:casi studio

ITA - - Il testo presenta sette schede di analisi e indirizzo su altrettanti casi studio rilevanti nel contesto regionale sardo. In esse sono sintetizzate le condizioni di fatto, le criticità emergenti e alcuni indirizzi per orientare gli interventi di riqualificazione e valorizzazione paesaggistica. - - ENGL - - The text reports seven analysis and guidelines related to some case studies relevant to the regional context of Sardinia. These reports synthesize the present conditions, the emerging critical aspects and some addresses to guide the enhancement and the valorisation of the landscape in the chosen case-studies

Fed-batch pre-industrial production and purification of a consensus tetratricopeptide repeat (CTPR) scaffold as a container for Fluorescent Proteins (FPs)

White light-emitting diodes (WLEDs) are big news in the field of lighting, however, current production processes are still very expensive or based on unsustainable inorganic metals such as inorganic phosphorus. The EU-funded ARTIBLED project aims to produce low-cost and high-efficiency Bio-hybrid light-emitting diodes (Bio-HLEDs). This can be achieved using artificially synthesized fluorescent proteins linked in biological scaffolds like the packaging to obtain LED for lighting applications containing a biogenic phosphor. This study aims to optimize the protein scaffold CTPR10 production process to obtain a high number of scaffolds with a good purity level for Bio-HLEDs construction. Different fed-batch fermentation procedures were investigated and it was possible to produce more than two times of biomass and intracellular proteins compared to a conventional fed-batch strategy. The improvement in production leads both to the reduction of costs related to the amount of IPTG used and the isolation of a consistent amount of CTPR10 through rapid and highly efficient purification techniques. The realization of this project represents a significant milestone for Europe which will be at the forefront of innovation in the lighting sector

Reduced graphene oxide as efficient and stable hole transporting material in mesoscopic perovskite solar cells

Perovskite solar cells (PSCs) are evolving with an impressive pace, emerging as the most promising next-generation photovoltaic devices. Nevertheless, beside these enormous progresses, the stability of PSCs remains one of the major problems to be challenged, because the most commonly used hole transporting material (HTM), the 2,2',7,7'-Tetrakis-(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD), suffers long-term stability. Here, we tackle this long-lasting issue exploiting reduced graphene oxide (RGO), prepared by an easy and efficient reduction method, as HTM in PSCs. We carried out endurance tests over 1987 h of shelf life and 120 h of light soaking. The PSCs based on RGO have shown power conversion efficiency (PCE) of 6.6%, outperforming the ones achieved with the Spiro-OMeTAD (PCE=6.5%), after the shelf life test. The light soaking test confirmed the better durability of RGO-based PSCs with respect to the Spiro-OMeTAD ones, the latter showing a reduction in PCE 2.7 times higher than the RGO-based cells. Moreover, we demonstrate by Open Circuit Voltage Decay measurements that RGO, beside the HTM function, acts also as an anti-recombination layer, reducing the charge carriers recombination pathways and, hence, increasing their lifetime. © 2016 Elsevier Ltd

Intensive Care Unit Physicians’ Perspectives on Artificial Intelligence–Based Clinical Decision Support Tools: Preimplementation Survey Study

Background: Artificial intelligence–based clinical decision support (AI-CDS) tools have great potential to benefit intensive care unit (ICU) patients and physicians. There is a gap between the development and implementation of these tools. Objective: We aimed to investigate physicians’ perspectives and their current decision-making behavior before implementing a discharge AI-CDS tool for predicting readmission and mortality risk after ICU discharge. Methods: We conducted a survey of physicians involved in decision-making on discharge of patients at two Dutch academic ICUs between July and November 2021. Questions were divided into four domains: (1) physicians’ current decision-making behavior with respect to discharging ICU patients, (2) perspectives on the use of AI-CDS tools in general, (3) willingness to incorporate a discharge AI-CDS tool into daily clinical practice, and (4) preferences for using a discharge AI-CDS tool in daily workflows. Results: Most of the 64 respondents (of 93 contacted, 69%) were familiar with AI (62/64, 97%) and had positive expectations of AI, with 55 of 64 (86%) believing that AI could support them in their work as a physician. The respondents disagreed on whether the decision to discharge a patient was complex (23/64, 36% agreed and 22/64, 34% disagreed); nonetheless, most (59/64, 92%) agreed that a discharge AI-CDS tool could be of value. Significant differences were observed between physicians from the 2 academic sites, which may be related to different levels of involvement in the development of the discharge AI-CDS tool. Conclusions: ICU physicians showed a favorable attitude toward the integration of AI-CDS tools into the ICU setting in general, and in particular toward a tool to predict a patient’s risk of readmission and mortality within 7 days after discharge. The findings of this questionnaire will be used to improve the implementation process and training of end users

Intensive Care Unit Physicians’ Perspectives on Artificial Intelligence–Based Clinical Decision Support Tools: Preimplementation Survey Study

Background: Artificial intelligence–based clinical decision support (AI-CDS) tools have great potential to benefit intensive care unit (ICU) patients and physicians. There is a gap between the development and implementation of these tools. Objective: We aimed to investigate physicians’ perspectives and their current decision-making behavior before implementing a discharge AI-CDS tool for predicting readmission and mortality risk after ICU discharge. Methods: We conducted a survey of physicians involved in decision-making on discharge of patients at two Dutch academic ICUs between July and November 2021. Questions were divided into four domains: (1) physicians’ current decision-making behavior with respect to discharging ICU patients, (2) perspectives on the use of AI-CDS tools in general, (3) willingness to incorporate a discharge AI-CDS tool into daily clinical practice, and (4) preferences for using a discharge AI-CDS tool in daily workflows. Results: Most of the 64 respondents (of 93 contacted, 69%) were familiar with AI (62/64, 97%) and had positive expectations of AI, with 55 of 64 (86%) believing that AI could support them in their work as a physician. The respondents disagreed on whether the decision to discharge a patient was complex (23/64, 36% agreed and 22/64, 34% disagreed); nonetheless, most (59/64, 92%) agreed that a discharge AI-CDS tool could be of value. Significant differences were observed between physicians from the 2 academic sites, which may be related to different levels of involvement in the development of the discharge AI-CDS tool. Conclusions: ICU physicians showed a favorable attitude toward the integration of AI-CDS tools into the ICU setting in general, and in particular toward a tool to predict a patient’s risk of readmission and mortality within 7 days after discharge. The findings of this questionnaire will be used to improve the implementation process and training of end users