A deep learning approach for determining the chiral indices of carbon nanotubes from high-resolution transmission electron microscopy images

Chiral indices determine important properties of carbon nanotubes (CNTs). Unfortunately, their determination from high-resolution transmission electron microscopy (HRTEM) images, the most accurate method for assigning chirality, is a tedious task. We develop a Convolutional Neural Network that automatizes this process. A large and realistic training data set of CNT images is obtained by means of atomistic computer simulations coupled with the multi-slice approach for image generation. In most cases, results of the automated assignment are in excellent agreement with manual classification, and the origin of failures is identified. The current approach, which combines HRTEM imaging and deep learning algorithms allows the analysis of a statistically significant number of HRTEM images of carbon nanotubes, paving the way for robust estimates of experimental chiral distributions.Comment: for use of the discussed computer code, please contact the corresponding autho

Reducing Non-Radiative Voltage Losses by Methylation of Push–Pull Molecular Donors in Organic Solar Cells

Organic solar cells are approaching power conversion efficiencies of other thin-film technologies. However, in order to become truly market competitive, the still substantial voltage losses need to be reduced. Here, the synthesis and characterization of four novel arylamine-based push-pull molecular donors was described, two of them exhibiting a methyl group at the para-position of the external phenyl ring of the arylamine block. Assessing the charge-transfer state properties and the effects of methylation on the open-circuit voltage of the device showed that devices based on methylated versions of the molecular donors exhibited reduced voltage losses due to decreased non-radiative recombination. Modelling suggested that methylation resulted in a tighter interaction between donor and acceptor molecules, turning into a larger oscillator strength to the charge-transfer states, thereby ensuing reduced non-radiative decay rates

Signatures of the Self-Similar Regime of Strongly Coupled Stimulated Brillouin Scattering for Efficient Short Laser Pulse Amplification

Plasma-based laser amplification is considered as a possible way to overcome the technological limits of present day laser systems and achieve exawatt laser pulses. Efficient amplification of a picosecond laser pulse by stimulated Brillouin scattering (SBS) of a pump pulse in a plasma requires to reach the self-similar regime of the strongly coupled (SC) SBS. In this Letter, we report on the first observation of the signatures of the transition from linear to self-similar regimes of SC-SBS, so far only predicted by theory and simulations. With a new fully head-on collision geometry, subpicosecond pulses are amplified by a factor of 5 with energy transfers of few tens of mJ. We observe pulse shortening, frequency spectrum broadening, and down-shifting for increasing gain, signatures of SC-SBS amplification entering the self-similar regime. This is also confirmed by the power law dependence of the gain on the amplification length: doubling the interaction length increases the gain by a factor 1.4. Pump backward Raman scattering (BRS) on SC-SBS amplification has been measured for the first time, showing a strong decrease of the BRS amplitude and frequency bandwidth when SBS seed amplification occurs

The efficacy of suppressive antibiotic treatment in patients managed non-operatively for periprosthetic joint infection and a draining sinus

Objectives: Patients with prosthetic joint infections (PJIs) not suitable for curative surgery may benefit from suppressive antibiotic therapy (SAT). However, the usefulness of SAT in cases with a draining sinus has never been investigated. Methods: A multicentre, retrospective observational cohort study was performed in which patients with a PJI and a sinus tract were eligible for inclusion if managed conservatively and if sufficient follow-up data were available (i.e. at least 2 years). SAT was defined as a period of > 6 months of oral antibiotic therapy. Results: SAT was initiated in 63 of 72 (87.5 %) included patients. Implant retention during follow-up was the same in patients receiving SAT vs. no SAT (79.4 % vs. 88.9 %; pCombining double low line0.68). In total, 27 % of patients using SAT experienced side effects. In addition, the occurrence of prosthetic loosening in initially fixed implants, the need for surgical debridement, or the occurrence of bacteremia during follow-up could not be fully prevented with the use of SAT, which still occurred in 42 %, 6.3 %, and 3.2 % of cases, respectively. However, the sinus tract tended to close more often (42 % vs. 13 %; pCombining double low line0.14), and a higher resolution of pain was observed (35 % vs. 14 %; pCombining double low line0.22) in patients receiving SAT. Conclusions: SAT is not able to fully prevent complications in patients with a draining sinus. However, it may be beneficial in a subset of patients, particularly in those with pain or the hindrance of a draining sinus. A future prospective study, including a higher number of patients not receiving SAT, is needed

Development and clinical validation of the Genedrive point-of-care test for qualitative detection of hepatitis C virus

Objective: Recently approved direct acting antivirals provide transformative therapies for chronic hepatitis C virus (HCV) infection. The major clinical challenge remains to identify the undiagnosed patients worldwide, many of whom live in low-income and middle-income countries, where access to nucleic acid testing remains limited. The aim of this study was to develop and validate a point-of-care (PoC) assay for the qualitative detection of HCV RNA. Design: We developed a PoC assay for the qualitative detection of HCV RNA on the PCR Genedrive instrument. We validated the Genedrive HCV assay through a case–control study comparing results with those obtained with the Abbott RealTime HCV test. Results: The PoC assay identified all major HCV genotypes, with a limit of detection of 2362 IU/mL (95% CI 1966 to 2788). Using 422 patients chronically infected with HCV and 503 controls negative for anti-HCV and HCV RNA, the Genedrive HCV assay showed 98.6% sensitivity (95% CI 96.9% to 99.5%) and 100% specificity (95% CI 99.3% to 100%) to detect HCV. In addition, melting peak ratiometric analysis demonstrated proof-of-principle for semiquantification of HCV. The test was further validated in a real clinical setting in a resource-limited country. Conclusion: We report a rapid, simple, portable and accurate PoC molecular test for HCV, with sensitivity and specificity that fulfils the recent FIND/WHO Target Product Profile for HCV decentralised testing in low-income and middle-income countries. This Genedrive HCV assay may positively impact the continuum of HCV care from screening to cure by supporting real-time treatment decisions

Mapping synergies and trade-offs between energy and the Sustainable Development Goals

The 2030 Agenda for Sustainable Development—including 17 interconnected Sustainable Development Goals (SDGs) and 169 targets—is a global plan of action for people, planet and prosperity. SDG7 calls for action to ensure access to affordable, reliable, sustainable and modern energy for all. Here we characterize synergies and trade-offs between efforts to achieve SDG7 and delivery of the 2030 Agenda as a whole. We identify 113 targets requiring actions to change energy systems, and published evidence of relationships between 143 targets (143 synergies, 65 trade-offs) and efforts to achieve SDG7. Synergies and trade-offs exist in three key domains, where decisions about SDG7 affect humanity’s ability to: realize aspirations of greater welfare and well-being; build physical and social infrastructures for sustainable development; and achieve sustainable management of the natural environment. There is an urgent need to better organize, connect and extend this evidence, to help all actors work together to achieve sustainable development. On 5 September 2015, the 193 members states of the United Nations (UN) adopted a new 2030 Agenda for Sustainable Development. The 2030 Agenda succeeds the UN’s Millennium Development Goals (MDGs), and features 17 Sustainable Development Goals (SDGs) with 169 targets, which UN member states have committed to implement by 2030. Energy was not explicitly referred to in the MDGs, and came to be referred to as the ‘missing’ MDG. During the operational period of the MDGs and negotiation of the 2030 Agenda, it was increasingly recognized that energy underpins economic and social development, without which it would not be possible to eliminate poverty. This change in status made sustainable energy provision and access one of the central themes of the 2030 Agenda, whose preamble calls for “universal access to affordable, reliable and sustainable energy” and recognizes that “social and economic development depends of the sustainable management of our planet’s natural resources”. SDG7 is accompanied by five targets to be achieved by 2030: ensure universal access to affordable, reliable and modern energy services (7.1); increase the share of renewable energy in the global energy mix (7.2); double the global rate of improvement in energy efficiency (7.3); enhance international cooperation to facilitate access to clean energy research and technology (7.a), and promote investment in energy infrastructure and clean energy technology (7.b). By understanding the complex links between the SDGs and their constituent targets, researchers can better support policymakers to think systematically about interactions between the different SDGs, including how actions to achieve each goal affect each other within and between sectors. Studies to date have lacked a target-level approach or have focussed on only a few of the SDGs. Here we present a formative attempt by an interdisciplinary group of researchers to identify the full range of goals and targets in the 2030 Agenda that call for changes in energy systems, and characterize evidence of synergies or trade-offs between delivery of each of the 169 targets and efforts focussed on pursuit of SDG7 and each of its constituent targets. The purpose of this Perspective is not to provide definitive answers. Instead we aim to lay a foundation for systematic (and context-specific) exploration of the interlinkages between each of the SDG targets, in the context of decision-making about development and the transformation of energy systems

Factors associated with return of spontaneous circulation after out-of-hospital cardiac arrest in Poland : a one-year retrospective study

Background: Out-of-hospital cardiac arrest (OHCA) is a common reason for calls for intervention by emergency medical teams (EMTs) in Poland. Regardless of the mechanism, OHCA is a state in which the chance of survival is dependent on rapid action from bystanders and responding health professionals in emergency medical services (EMS). We aimed to identify factors associated with return of spontaneous circulation (ROSC). Methods: The medical records of 2137 EMS responses to OHCA in the city of Wroclaw, Poland between July 2017 and June 2018 were analyzed. Results: The OHCA incidence rate for the year studied was 102 cases per 100,000 inhabitants. EMS were called to 2317 OHCA events of which 1167 (50.4%) did not have resuscitation attempted on EMS arrival. The difference between the number of successful and failed cardiopulmonary resuscitations (CPRs) was statistically significant (p < 0.001). Of 1150 patients in whom resuscitation was attempted, ROSC was achieved in 250 (27.8%). Rate of ROSC was significantly higher when CPR was initiated by bystanders (p < 0.001). Patients presenting with asystole or pulseless electrical activity (PEA) had a higher risk of CPR failure (86%) than those with ventricular fibrillation/ventricular tachycardia (VF/VT). Patients with VF/VT had a higher chance of ROSC (OR 2.68, 1.86–3.85) than those with asystole (p < 0.001). The chance of ROSC was 1.78 times higher when the event occurred in a public place (p < 0.001). Conclusions: The factors associated with ROSC were occurrence in a public place, CPR initiation by witnesses, and presence of a shockable rhythm. Gender, age, and the type of EMT did not influence ROSC. Low bystander CPR rates reinforce the need for further efforts to train the public in CPR

Insight into response to mTOR inhibition when PKD1 and TSC2 are mutated

Altres ajuts: Novartis PharmaceuticalMutations in TSC1 or TSC2 cause the tuberous sclerosis complex (TSC), while mutations in PKD1 or PKD2 cause autosomal dominant polycystic kidney disease (ADPKD). PKD1 lays immediately adjacent to TSC2 and deletions involving both genes, the PKD1/TSC2 contiguous gene syndrome (CGS), are characterized by severe ADPKD, plus TSC. mTOR inhibitors have proven effective in reducing angiomyolipoma (AML) in TSC and total kidney volume in ADPKD but without a positive effect on renal function. We describe a patient with independent truncating PKD1 and TSC2 mutations who has the expected phenotype for both diseases independently instead of the severe one described in PKD1/TSC2 -CGS. Treatment with mTOR inhibitors reduced the AML and kidney volume for 2 years but thereafter they resumed growth; no positive effect on renal function was seen throughout. This is the first case addressing the response to mTOR treatment when independent truncating mutations in PKD1 and TSC2 are present. This case reveals that although PKD1 and TSC2 are adjacent genes and there is likely cross-talk between the PKD1 and TSC2 signalling pathways regulating mTOR, having independent TSC2 and PKD1 mutations can give rise to a milder kidney phenotype than is typical in PKD1/TSC2 -CGS cases. A short-term beneficial effect of mTOR inhibition on AML and total kidney volume was not reflected in improved renal function