Abstract Recently, the interest in the Helmet interface during non-invasive respiratory support (NIRS) has increased due to the COVID-19 pandemic. During NIRS, positive end-expiratory pressure (PEEP) ...can be given as continuous positive airway pressure (CPAP), which maintains a positive airway pressure throughout the whole respiratory cycle with Helmet as an interface (H-CPAP). The main disadvantage of the H-CPAP is the inability to measure tidal volume (V T ). Opto-electronic plethysmography (OEP) is a non-invasive technique that is not sensitive to gas compression/expansion inside the helmet. OEP acquisitions were performed on 28 healthy volunteers (14 females and 14 males) at baseline and during Helmet CPAP. The effect of posture (semi-recumbent vs. prone), flow (50 vs. 60 L/min), and PEEP (0 vs. 5 vs. 10 cmH 2 O) on the ventilatory and thoracic-abdominal pattern and the operational volumes were investigated. Prone position limited vital capacity, abdominal expansion and chest wall recruitment. A constant flow of 60 L/min reduced the need for the subject to ventilate while having a slight recruitment effect (100 mL) in the semi-recumbent position. A progressive increasing recruitment was found with higher PEEP but limited by the prone position. It is possible to accurately measure tidal volume during H-CPAP to deliver non-invasive ventilatory support using opto-electronic plethysmography during different clinical settings.
We discovered 2.8 s pulsations in the X-ray emission of the ultraluminous X-ray source (ULX) M51 ULX-7 within the UNSEeN project, which was designed to hunt for new pulsating ULXs (PULXs) with ...XMM-Newton. The pulse shape is sinusoidal, and large variations of its amplitude were observed even within single exposures (pulsed fraction from less than 5% to 20%). Source M51 ULX-7 is variable, generally observed at an X-ray luminosity between 1039 and 1040 erg s−1, located in the outskirts of the spiral galaxy M51a at a distance of 8.6 Mpc. According to our analysis, the X-ray pulsar orbits in a 2 day binary with a projected semimajor axis 28 lt-s. For a neutron star (NS) of 1.4 M , this implies a lower limit on the companion mass of 8 M , placing the system hosting M51 ULX-7 in the high-mass X-ray binary class. The barycentric pulse period decreased by 0.4 ms in the 31 days spanned by our 2018 May-June observations, corresponding to a spin-up rate . In an archival 2005 XMM-Newton exposure, we measured a spin period of ∼3.3 s, indicating a secular spin-up of , a value in the range of other known PULXs. Our findings suggest that the system consists of a massive donor, possibly an OB giant or supergiant, and a moderately magnetic (dipole field component in the range 1012 G G) accreting NS with weakly beamed emission ( ).
ABSTRACT We present multi-wavelength observations of the unassociated γ-ray source 3FGL J2039.6−5618 detected by the Fermi Large Area Telescope. The source γ-ray properties suggest that it is a ...pulsar, most likely a millisecond pulsar, for which neither radio nor γ-ray pulsations have been detected. We observed 3FGL J2039.6−5618 with XMM-Newton and discovered several candidate X-ray counterparts within/close to the γ-ray error box. The brightest of these X-ray sources is variable with a period of 0.2245 0.0081 days. Its X-ray spectrum can be described by a power law with photon index ΓX = 1.36 0.09, and hydrogen column density NH < 4 × 1020 cm−2, which gives an unabsorbed 0.3-10 keV X-ray flux of 1.02 × 10−13 erg cm−2 s−1. Observations with the Gamma-Ray Burst Optical/Near-Infrared Detector discovered an optical counterpart to this X-ray source, with a time-averaged magnitude g′ ∼ 19.5. The counterpart features a flux modulation with a period of 0.22748 0.00043 days that coincides, within the errors, with that of the X-ray source, confirming the association based on the positional coincidence. We interpret the observed X-ray/optical periodicity as the orbital period of a close binary system where one of the two members is a neutron star. The light curve profile of the companion star, which has two asymmetric peaks, suggests that the optical emission comes from two regions with different temperatures on its tidally distorted surface. Based upon its X-ray and optical properties, we consider this source as the most likely X-ray counterpart to 3FGL J2039.6−5618, which we propose to be a new redback system.
Insulin resistance is a key mediator of obesity-related cardiometabolic disease, yet the mechanisms underlying this link remain obscure. Using an integrative genomic approach, we identify 53 genomic ...regions associated with insulin resistance phenotypes (higher fasting insulin levels adjusted for BMI, lower HDL cholesterol levels and higher triglyceride levels) and provide evidence that their link with higher cardiometabolic risk is underpinned by an association with lower adipose mass in peripheral compartments. Using these 53 loci, we show a polygenic contribution to familial partial lipodystrophy type 1, a severe form of insulin resistance, and highlight shared molecular mechanisms in common/mild and rare/severe insulin resistance. Population-level genetic analyses combined with experiments in cellular models implicate CCDC92, DNAH10 and L3MBTL3 as previously unrecognized molecules influencing adipocyte differentiation. Our findings support the notion that limited storage capacity of peripheral adipose tissue is an important etiological component in insulin-resistant cardiometabolic disease and highlight genes and mechanisms underpinning this link.
A triphasic scaffold (TPS) for the regeneration of the bone-ligament interface was fabricated combining a 3D fiber deposited polycaprolactone structure and a polylactic co-glycolic acid electrospun. ...The scaffold presented a gradient of physical and mechanical properties which elicited different biological responses from human mesenchymal stem cells. Biological test were performed on the whole TPS and on scaffolds comprised of each single part of the TPS, considered as the controls. The TPS showed an increase of the metabolic activity with culturing time that seemed to be an average of the controls at each time point. The importance of differentiation media for bone and ligament regeneration was further investigated. Metabolic activity analysis on the different areas of the TPS showed a similar trend after 7 days in both differentiation media. Total alkaline phosphatase (ALP) activity analysis showed a statistically higher activity of the TPS in mineralization medium compared to the controls. A different glycosaminoglycans amount between the TPS and its controls was detected, displaying a similar trend with respect to ALP activity. Results clearly indicated that the integration of electrospinning and additive manufacturing represents a promising approach for the fabrication of scaffolds for the regeneration of tissue interfaces, such as the bone-to-ligament one, because it allows mimicking the structural environment combining different biomaterials at different scales.
A generic chemical transformation may often be achieved under various synthetic conditions. However, for any specific reagents, only one or a few among the reported synthetic protocols may be ...successful. For example, Michael β-addition reactions may proceed under different choices of solvent (e.g., hydrophobic, aprotic polar, protic) and catalyst (e.g., Brønsted acid, Lewis acid, Lewis base, etc.). Chemoinformatics methods could be efficiently used to establish a relationship between the reagent structures and the required reaction conditions, which would allow synthetic chemists to waste less time and resources in trying out various protocols in search for the appropriate one. In order to address this problem, a number of 2-classes classification models have been built on a set of 198 Michael reactions retrieved from literature. Trained models discriminate between processes that are compatible and respectively processes not feasible under a specific reaction condition option (feasible or not with a Lewis acid catalyst, feasible or not in hydrophobic solvent, etc.). Eight distinct models were built to decide the compatibility of a Michael addition process with each considered reaction condition option, while a ninth model was aimed to predict whether the assumed Michael addition is feasible at all. Different machine-learning methods (Support Vector Machine, Naive Bayes, and Random Forest) in combination with different types of descriptors (ISIDA fragments issued from Condensed Graphs of Reactions, MOLMAP, Electronic Effect Descriptors, and Chemistry Development Kit computed descriptors) have been used. Models have good predictive performance in 3-fold cross-validation done three times: balanced accuracy varies from 0.7 to 1. Developed models are available for the users at http://infochim.u-strasbg.fr/webserv/VSEngine.html. Eventually, these were challenged to predict feasibility conditions for ∼50 novel Michael reactions from the eNovalys database (originally from patent literature).
IMPORTANCE: Body fat distribution, usually measured using waist-to-hip ratio (WHR), is an important contributor to cardiometabolic disease independent of body mass index (BMI). Whether mechanisms ...that increase WHR via lower gluteofemoral (hip) or via higher abdominal (waist) fat distribution affect cardiometabolic risk is unknown. OBJECTIVE: To identify genetic variants associated with higher WHR specifically via lower gluteofemoral or higher abdominal fat distribution and estimate their association with cardiometabolic risk. DESIGN, SETTING, AND PARTICIPANTS: Genome-wide association studies (GWAS) for WHR combined data from the UK Biobank cohort and summary statistics from previous GWAS (data collection: 2006-2018). Specific polygenic scores for higher WHR via lower gluteofemoral or via higher abdominal fat distribution were derived using WHR-associated genetic variants showing specific association with hip or waist circumference. Associations of polygenic scores with outcomes were estimated in 3 population-based cohorts, a case-cohort study, and summary statistics from 6 GWAS (data collection: 1991-2018). EXPOSURES: More than 2.4 million common genetic variants (GWAS); polygenic scores for higher WHR (follow-up analyses). MAIN OUTCOMES AND MEASURES: BMI-adjusted WHR and unadjusted WHR (GWAS); compartmental fat mass measured by dual-energy x-ray absorptiometry, systolic and diastolic blood pressure, low-density lipoprotein cholesterol, triglycerides, fasting glucose, fasting insulin, type 2 diabetes, and coronary disease risk (follow-up analyses). RESULTS: Among 452 302 UK Biobank participants of European ancestry, the mean (SD) age was 57 (8) years and the mean (SD) WHR was 0.87 (0.09). In genome-wide analyses, 202 independent genetic variants were associated with higher BMI-adjusted WHR (n = 660 648) and unadjusted WHR (n = 663 598). In dual-energy x-ray absorptiometry analyses (n = 18 330), the hip- and waist-specific polygenic scores for higher WHR were specifically associated with lower gluteofemoral and higher abdominal fat, respectively. In follow-up analyses (n = 636 607), both polygenic scores were associated with higher blood pressure and triglyceride levels and higher risk of diabetes (waist-specific score: odds ratio OR, 1.57 95% CI, 1.34-1.83, absolute risk increase per 1000 participant-years ARI, 4.4 95% CI, 2.7-6.5, P < .001; hip-specific score: OR, 2.54 95% CI, 2.17-2.96, ARI, 12.0 95% CI, 9.1-15.3, P < .001) and coronary disease (waist-specific score: OR, 1.60 95% CI, 1.39-1.84, ARI, 2.3 95% CI, 1.5-3.3, P < .001; hip-specific score: OR, 1.76 95% CI, 1.53-2.02, ARI, 3.0 95% CI, 2.1-4.0, P < .001), per 1-SD increase in BMI-adjusted WHR. CONCLUSIONS AND RELEVANCE: Distinct genetic mechanisms may be linked to gluteofemoral and abdominal fat distribution that are the basis for the calculation of the WHR. These findings may improve risk assessment and treatment of diabetes and coronary disease.
Abstract
Common quantum frameworks of light–matter coupling demonstrate the interaction between an atom and a cavity occurring through a single feedback channel: an exciton relaxes by emitting a ...photon that is stored in the cavity for several roundtrips before being re-absorbed to create another exciton, and so on. However, the possibility for the excited system to relax through two different channels belonging to two different regimes has been, until now, neglected. Here, we investigate the case in which the strong coupling regime and the photovoltaic effect cooperate to enhance the wavelength-dependent photocurrent conversion efficiency (defined as the incident photons to converted electrons ratio, namely the external quantum efficiency—EQE) of a photovoltaic cell specifically engineered to behave as an optical cavity tuned to the excitonic transition of the embedded active material (CH
3
NH
3
PbI
3
perovskite). We exploit the angular dispersion of such photovoltaic cell to show that when the cavity mode approaches the energy of the exciton, the strong coupling regime is achieved and the EQE is significantly enhanced with respect to a classic configuration serving as a benchmark. Our findings do not aim at demonstrating an immediate impact in enhancing the performance of photovoltaic systems but, rather, constitute a proof-of-principle experimental demonstration of how the photovoltaic effect can benefit from the generation of polaritons. Nonetheless, such a peculiar cooperating dual-light–matter interaction could be exploited in future polaritonic photovoltaic architectures.
Hyperbolic Metamaterials are artificially engineered materials whose optical properties can be specifically tailored to manifest an extremely high level of anisotropy. Due to this remarkable ...anisotropy they represent a unique opportunity to realize effective bulk meta-structure with extraordinary optical properties in the visible range. A simultaneous dielectric singularity in the in plane permittivity, with respect to the propagation direction, has to lead to a complete sign inversion of the same permittivity for that specific visible frequency. Such a drastic phase change has been theoretically highlighted in the past as the major challenge to be overcome in order to unlock many remarkable optical properties not present artificial optical systems. In this paper we experimentally demonstrate the realization of a metal-dielectric multilayer structure showing an inversion point of coexisting anisotropies at a specified wavelength in the visible range, rising from the particular design and fabrication process. Theoretical models and numerical simulations are in very good agreement with experimental data. Ellipsometrical experiments and optical modeling demonstrate the drastic type I/type II transition. Supercollimation effect has been achieved at the inversion point of the coexisting extreme anisotropies, whereas at the epsilon near zero and pole frequency the perfect lens behavior has been observed.
Aim
Chylothorax is a rare but life‐threatening condition in newborns. Octreotide, a somatostatin analogue, is widely used as a therapeutic option in neonates with congenital and acquired chylothorax, ...but its therapeutic role has not been clarified yet.
Methods
We performed a systematic review to assess the efficacy and safety of octreotide in the treatment of congenital and acquired chylothorax in newborns. Comprehensive research, updated till 31 October 2017, was performed by searching in PubMed, MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials (CENTRAL) databases using the MeSH terms ‘octreotide’ and ‘chylothorax’. Both term and preterm newborns with congenital or acquired chylothorax treated with octreotide within the 30th day of life were included. Octreotide treatment was considered effective if a progressive reduction/ceasing in drained chylous effusion occurred.
Results
A total of 39 articles were included. Octreotide was effective in 47% of patients, with a slight but not significant difference between congenital (30/57; 53.3%) and acquired (9/27; 33.3%) chylothorax (P = 0.10). Marked variation in octreotide regimen was observed. The most common therapeutic scheme was intravenous infusion at a starting dose of 1 μg/kg/h, gradually increasing to 10 μg/kg/h according to the therapeutic response. Side effects were reported in 12 of 84 patients (14.3%). Only case reports were included in this review due to the lack of randomised controlled trials.
Conclusion
Octreotide is a relatively effective and safe treatment option in neonates with chylothorax, especially for the congenital forms.
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