julilili42/papers huggingface dataset:
High-frequency asymptotics of the vertex function: Diagrammatic parametrization and algorithmic implementation
2020-08-03

Vertex functions are a crucial ingredient of several forefront many-body algorithms in condensed matter physics. However, the full treatment of their frequency and momentum dependence severely restricts numerical calculations. A significant advancement requires an efficient treatment of the high-frequency asymptotic behavior of the vertex functions. In this work, we first provide a detailed diagrammatic analysis of the high-frequency structures and their physical interpretation. Based on these insights, we propose a parametrization scheme, which captures the whole high-frequency domain for arbitrary values of the Coulomb interaction and electronic density, and we discuss the details of its algorithmic implementation in many-body solvers based on parquet-equations as well as functional renormalization group schemes. Finally, we assess its validity by comparing our results for a single impurity Anderson model with exact diagonalization calculations. The proposed parametrization is pivotal for the algorithmic development of all quantum many-body methods based on vertex functions arising from both local and non-local static microscopic interactions as well as effective dynamic interactions which uniformly approach a static value for large frequencies. In this way, our present technique can substantially improve vertex-based diagrammatic approaches including spatial correlations beyond dynamical mean-field theory.
Living-Donor Uterus Transplantation: Pre-, Intra-, and Postoperative Parameters Relevant to Surgical Success, Pregnancy, and Obstetrics with Live Births
2020-08-03

Uterus transplantation (UTx) can provide a route to motherhood for women with Mayer–Rokitansky–Küster–Hauser syndrome (MRKHS), a congenital disorder characterized by uterovaginal aplasia, but with functional ovaries. Based on our four successful living-donor transplantations and two resulting births, this analysis presents parameters relevant to standardizing recipient/donor selection, UTx surgery, and postoperative treatment, and their implementation in routine settings. We descriptively analyzed prospectively collected observational data from our four uterus recipients, all with MRKHS, their living donors, and the two newborns born to two recipients, including 1-year postnatal follow-ups. Analysis included only living-donor/recipient pairs with completed donor/recipient surgery. Two recipients, both requiring ovarian restimulation under immunosuppression after missed pregnancy loss in one case and no pregnancy in the other, each delivered a healthy boy by cesarean section. We conclude that parameters crucial to successful transplantation, pregnancy, and childbirth include careful selection of donor/recipient pairs, donor organ quality, meticulous surgical technique, a multidisciplinary team approach, and comprehensive follow-up. Surgery duration and blood vessel selection await further optimization, as do the choice and duration of immunosuppression, which are crucial to timing the first embryo transfer. Data need to be collected in an international registry due to the low prevalence of MRKHS.
Onset features and time to diagnosis in Friedreich’s Ataxia
2020-08-03

Abstract Background In rare disorders diagnosis may be delayed due to limited awareness and unspecific presenting symptoms. Herein, we address the issue of diagnostic delay in Friedreich’s Ataxia (FRDA), a genetic disorder usually caused by homozygous GAA-repeat expansions. Methods Six hundred eleven genetically confirmed FRDA patients were recruited within a multicentric natural history study conducted by the EFACTS (European FRDA Consortium for Translational Studies, ClinicalTrials.gov -Identifier NCT02069509). Age at first symptoms as well as age at first suspicion of FRDA by a physician were collected retrospectively at the baseline visit. Results In 554 of cases (90.7%), disease presented with gait or coordination disturbances. In the others ( n = 57, 9.3%), non-neurological features such as scoliosis or cardiomyopathy predated ataxia. Before the discovery of the causal mutation in 1996, median time to diagnosis was 4(IQR = 2–9) years and it improved significantly after the introduction of genetic testing (2(IQR = 1–5) years, p &lt; 0.001). Still, after 1996, time to diagnosis was longer in patients with a) non-neurological presentation (mean 6.7, 95%CI [5.5,7.9] vs 4.5, [4.2,5] years in those with neurological presentation, p = 0.001) as well as in b) patients with late-onset (3(IQR = 1–7) vs 2(IQR = 1–5) years compared to typical onset &lt; 25 years of age, p = 0.03). Age at onset significantly correlated with the length of the shorter GAA repeat (GAA1) in case of neurological onset (r = − 0,6; p &lt; 0,0001), but not in patients with non-neurological presentation (r = − 0,1; p = 0,4). Across 54 siblings’ pairs, differences in age at onset did not correlate with differences in GAA-repeat length (r = − 0,14, p = 0,3). Conclusions In the genetic era, presentation with non-neurological features or in the adulthood still leads to a significant diagnostic delay in FRDA. Well-known correlations between GAA1 repeat length and disease milestones are not valid in case of atypical presentations or positive family history.
Prices, availability and affordability of medicines in Rwanda
2020-08-03

In Rwanda, medicines are affordable but poorly available in both the public and the faith-based sectors. Further improvements of the availability of medicines in the public and the faith-based health facilities represent the most important key to increase accessibility and affordability of medicines in Rwanda.
Evaluation of three fully-automated SARS-CoV-2 antibody assays
2020-08-03

Abstract Objectives Serological assays for detection of SARS-CoV-2 antibodies are increasingly used during the COVID-19 pandemic caused by the SARS-Coronavirus-2. Here we evaluated the analytical and clinical performance of three commercially available SARS-CoV-2 antibody assays. Methods A total of 186 samples from 58 patients with PCR-confirmed COVID-19 infection were measured using SARS-CoV-2 antibody assays by Siemens Healthineers, Roche Diagnostics and Euroimmun. Additionally, 123 control samples, including samples collected before December 2019 and samples with potential cross-reactive antibodies were analyzed. Diagnostic specificity, sensitivity, agreement between assays and ROC curve-derived optimized thresholds were determined. Furthermore, intra- and inter-assay precision and the potential impact of interfering substances were investigated. Results SARS-CoV-2 antibody assays by Siemens and Roche showed 100% specificity. The Euroimmun assay had 98 and 100% specificity, when borderline results are considered as positive or negative, respectively. Diagnostic sensitivity for samples collected ≥14 days after PCR-positivity was 97.0, 89.4 and 95.5% using the Siemens, Roche and Euroimmun assay, respectively. Sensitivity of the Roche assay can be increased using an optimized cut-off index (0.095). However, a simultaneous decrease in specificity (98.4%) was observed. Siemens showed 95.8 and 95.5% overall agreement with results of Euroimmun and Roche assay, respectively. Euroimmun and Roche assay exhibited 92.6% overall agreement. Discordant results were observed in three COVID-19 patients and in one COVID-19 patient none of the investigated assays detected antibodies. Conclusions The investigated assays were highly specific and sensitive in detecting SARS-CoV-2 antibodies in samples obtained ≥14 days after PCR-confirmed infection. Discordant results need to be investigated in further studies.
Hip Revision Arthroplasty of Periprosthetic Fractures Vancouver B2and B3 with a Modular Revision Stem: Short-Term Results and Review ofLiterature
2020-08-03

Abstract Background Periprosthetic fractures Vancouver type B2/B3 after total hip arthroplasty (THA) is a challenging entity with increasing numbers. Limited data are available for this type of fracture treated with modular stems. Therefore, this study evaluated the outcome of Vancouver type B2/B3 fractures treated with a modular hip revision stem using a subproximal/distal anchorage and compared it to the current literature. Materials and Methods A consecutive series of periprosthetic Vancouver type B2/B3 fractures treated with a modular revision stem was retrospectively (2013 – 2016) evaluated. Assessment included the clinical (HHS, pain, ROM) as well as the radiological outcome (subsidence, loosening, facture healing). In adddition, the surgical technique is described in detail and results are compared with the current literature. Results A total of 18 patients (female/male 12/6) with Vancouver B2/B3 (n = 12/6) fractures with a mean age of 75.5 (60 – 89) years were included. The revision stem was inserted via a modified transgluteal approach (n = 16) or classical transfemoral approach (n = 2). The mean follow-up was 18.5 months, with a mean Harris Hip Score of 72.5 ± 18.7 (35.0 – 99.0) points. The fracture healing rate was 94.4% (n = 17) with osseous integration according to Engh in all cases. Dislocations of the greater trochanter were recorded in seven patients (38.9%). According to Beals and Towers, all results were rated excellent or good. No implant-related failure or relevant subsidence during this time was observed. Major complications were observed in five patients with two periprosthetic joint infections and two cases of major revision surgery. Conclusion This study assessing Vancouver B2/3 fractures shows reproducible, good, short-term results in terms of subsidence and clinical functional outcome by the use of a modular revision stem. The transfemoral approach together with the modular stem allows for a stable fixation and good fracture healing. However, our data and review of the literature also documents the difficulties and higher complication rate associated with Vancouver B2/3 fractures.
Activation of Epidermal Growth Factor Receptor Sensitizes Glioblastoma Cells to Hypoxia-Induced Cell Death
2020-08-03

Background: The epidermal growth factor receptor (EGFR) signaling pathway is genetically activated in approximately 50% of glioblastomas (GBs). Its inhibition has been explored clinically but produced disappointing results, potentially due to metabolic effects that protect GB cells against nutrient deprivation and hypoxia. Here, we hypothesized that EGFR activation could disable metabolic adaptation and define a GB cell population sensitive to starvation. Methods: Using genetically engineered GB cells to model different types of EGFR activation, we analyzed changes in metabolism and cell survival under conditions of the tumor microenvironment. Results: We found that expression of mutant EGFRvIII as well as EGF stimulation of EGFR-overexpressing cells impaired physiological adaptation to starvation and rendered cells sensitive to hypoxia-induced cell death. This was preceded by adenosine triphosphate (ATP) depletion and an increase in glycolysis. Furthermore, EGFRvIII mutant cells had higher levels of mitochondrial superoxides potentially due to decreased metabolic flux into the serine synthesis pathway which was associated with a decrease in the NADPH/NADP+ ratio. Conclusions: The finding that EGFR activation renders GB cells susceptible to starvation could help to identify a subgroup of patients more likely to benefit from starvation-inducing therapies.
Dust and gas absorption in the high mass X-ray binary IGR J16318−4848
2020-08-03

Context. With an absorption column density on the order of 10 24 cm −2 , IGR J16318−4848 is one of the most extreme cases of a highly obscured high mass X-ray binary. In addition to the overall continuum absorption, the source spectrum exhibits a strong iron and nickel fluorescence line complex at 6.4 keV. Previous empirical modeling of these features and comparison with radiative transfer simulations raised questions about the structure and covering fraction of the absorber and the profile of the fluorescence lines. Aims. We aim at a self-consistent description of the continuum absorption, the absorption edges, and the fluorescence lines to constrain the properties of the absorbing material, such as ionization structure and geometry. We further investigate the effects of dust absorption on the observed spectra and the possibility of fluorescence emission from dust grains. Methods. We used XMM - Newton and NuSTAR spectra to first empirically constrain the incident continuum and fluorescence lines. Next we used XSTAR to construct a customized photoionization model where we vary the ionization parameter, column density, and covering fraction. In the third step we modeled the absorption and fluorescence in a dusty olivine absorber and employed both a simple analytical model for the fluorescence line emission and a Monte Carlo simulation of radiative transfer that generates line fluxes, which are very close to the observational data. Results. Our empirical spectral modeling is in agreement with previous works. Our second model, the single gas absorber does not describe the observational data. In particular, irrespective of the ionization state or column density of the absorber, a much higher covering fraction than previously estimated is needed to produce the strong fluorescence lines and the large continuum absorption. A dusty, spherical absorber (modeled as consisting of olivine dust, although the nature of dust cannot be constrained) is able to produce the observed continuum absorption and edges. Conclusions. A dense, dusty absorber in the direct vicinity of the source consisting of dust offers a consistent description of both the strong continuum absorption and the strong emission features in the X-ray spectrum of IGR J16318−4848. In particular, for low optical depth of individual grains, which is the case for typical volume densities and grain size distribution models, the dust will contribute significantly to the fluorescence emission.
Antimicrobial Compounds from the Mucus of Garden Snail <em>Cornu aspersa</em>
2020-08-03

Natural products have long played a major role in medicine and science. The garden snail Cornu aspersa is a rich source of biologically active natural substances which might be an important source for new drugs to treat human disease. Based on our previous studies seven fractions containing compounds with Mw &amp;amp;lt;3 kDa, &amp;amp;lt;10 kDa, &amp;amp;lt;20 kDa, &amp;amp;gt;20 kDa, and between 3-5 kDa, 5-10 kDa, and 10-30 kDa were purified from the mucus of C. aspersa and analyzed by tandem mass spectrometry (MALDI-TOF/TOF). Seventeen novel peptides with potential antibacterial activity have been identified by de novo MS/MS sequencing using tandem mass spectrometry. The different fractions were tested for antibacterial activity against Gram─ (Pseudomonas aureofaciens and Escherichia coli) and Gram+ (Brevibacillus laterosporus) bacterial strains as well anaerobic bacterium Clostridium perfringens. These results revealed that the peptide fractions exhibit a predominant antibacterial activity against B. laterosporus, the fraction with Mw 10 &amp;ndash; 30 kDa against E. coli, another peptide fraction &amp;amp;lt;20 kDa against P. aureofaciens, and the protein fraction &amp;amp;gt;20 kDa against the bacterial strain C. perfringens. The discovery of new antimicrobial peptides (AMPs) from natural sources is of great importance for public health due to their effective antimicrobial activities and low resistance rates.
Pronounced Heterotopic Ossifications after TraumaticHamstring Rupture: Is an Ossification Prophylaxis Useful?
2020-08-03

Abstract Hamstring injuries include a wide range of injuries and affect mainly athletes with high eccentric loads (football, athletics, rugby, climbing). According to the latest literature, unrecognized traumatic ruptures can cause permanent discomfort and may be associated with a poorer postoperative outcome when delayed surgical therapy is performed. Heterotopic ossifications (HO) after hamstring rupture have been described in individual case reports and smaller studies so far. Heterotopic ossifications are mainly known in hip surgery and elbow fractures. In this case report, a 48-year-old patient presented with an increasing swelling with hardening in the area of the right ischial tuberosity. One year before, an impact trauma was the reason for a traumatic hamstring rupture which was diagnosed with a delay. The HO was excised and the tendon refixed with two suture anchors. By limiting the range of motion with a hip-knee orthosis for 9 weeks, a regular postoperative healing process was observed. Heterotopic ossifications after hamstring ruptures have been reported repeatedly but have not been evaluated in any major study so far. It should therefore be considered whether prophylaxis with NSAIDs should be used for conservatively and surgically treated hamstring ruptures, analogous to the ossification prophylaxis for hip endoprostheses or fractures in the elbow region.
Accelerating black holes: Quasinormal modes and late-time tails
2020-08-04

Black holes found in binaries move at very high velocities relative to our\\nown reference frame and can accelerate due to the emission of gravitational\\nradiation. Here, we investigate the numerical stability and late-time behavior\\nof linear scalar perturbations in accelerating black holes described by the\\n metric. We identify a family of quasinormal modes associated with the\\nphoton surface and a brand new family of purely imaginary modes associated with\\nthe boost parameter of the accelerating black hole spacetime. When the\\naccelerating black hole is charged, we find a third family of modes which\\ndominates the ringdown waveform near extremality. Our frequency and time domain\\nanalysis indicate that such spacetimes are stable under scalar fluctuations,\\nwhile the late-time behavior follows an exponential decay law, dominated by\\nquasinormal modes. This result is in contrast with the common belief that such\\nperturbations, for black holes without a cosmological constant, always have a\\npower-law cutoff. In this sense, our results suggest that the asymptotic\\nstructure of black hole backgrounds does not always dictate how radiative\\nfields behave at late times.\\n
Clinical cases referring to current options and recommendations for the use of thoracic endovascular aortic repair in acute and chronic thoracic aortic disease: an expert consensus document of the European Society for Cardiology (ESC) Working Group of Cardiovascular Surgery, the ESC Working Group on Aorta and Peripheral Vascular Diseases, the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC and the European Association for Cardio-Thoracic Surgery (EACTS)
2020-08-04

This compilation of clinical cases is meant as a companion to the document ‘Current options and recommendations for the use of thoracic endovascular aortic repair (TEVAR) in acute and chronic thoracic aortic disease: an expert consensus document of the European Society for Cardiology (ESC) Working Group of Cardiovascular Surgery, the ESC Working Group on Aorta &amp;amp; Peripheral Vascular Diseases, the European Association of Percutaneous Cardiovascular Interventions (EAPCI) of the ESC and the European Association for Cardio-Thoracic Surgery (EACTS)’.
Increased Hepatic ACE2 Expression in NAFL and Diabetes—A Risk for COVID-19 Patients?
2020-08-04

The current pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced disease (coronavirus disease 2019 [COVID-19]) is a major global threat.Although most infected patients have a mild course, a relevant proportion of approximately 20% develop a severe and often lethal condition.Recent findings demonstrate that COVID-19 is a multiorgan disease.In addition to the characteristic pneumonia, it affects heart, kidney, pancreas, the coagulation system, and liver.Major risk factors for severe COVID-19 with multiorgan complications include male sex, older age (.65 years), cardiovascular and chronic lung disease, and especially diabetes (1,2).However, it is still unclear why these conditions predispose to a severe course of COVID-19.To enter the target cell, SARS-CoV-2 requires the binding of its spike protein to the angiotensin-converting enzyme 2 (ACE2) receptor (3).The entry is additionally facilitated by subsequent priming and cleavage of the spike protein through proteases such as transmembrane serine protease 2 (TPMRSS2) and furin (3).While the ACE2 receptor is mainly expressed in heart, lungs, endothelial cells, kidney, and the gastrointestinal tract, expression has also been detected in cholangiocytes and
Chemoresistive CO2 Gas Sensors Based On La2O2CO3: Sensing Mechanism Insights Provided by Operando Characterization
2020-08-04

Our previous studies demonstrated that rare-earth oxycarbonates Ln<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> (Ln = La, Nd, and Sm) and rare-earth oxides Ln<sub>2</sub>O<sub>3</sub> (Ln = Nd, Sm, Gd, Dy, Er, and Yb) are sensitive to CO<sub>2</sub> and that hexagonal La<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> is the best among them in terms of sensitivity, stability, and selectivity. In this study, we have conducted a comprehensive operando characterization on a hexagonal La<sub>2</sub>O<sub>2</sub>CO<sub>3</sub> based sensor for the basic understanding of the sensing mechanism. This was done by performing under actual operating conditions simultaneous DC resistance and work function changes measurements, AC impedance spectroscopy measurements, and simultaneous DC resistance and DRIFT spectroscopy measurements. The results demonstrate that the double Schottky barriers at grain-grain boundaries are dominant contribution to sensor resistance; there is a competitive adsorption between carbonate species and hydroxyl groups, which depends on both CO<sub>2</sub> concentration and humidity and leads to the change in height of the Schottky barriers. Finally, we propose a reaction model stating that there are three types of adsorbates, -CO<sub>3</sub><sup>2-</sup>, -OH<sup>-</sup>, and -O<sup>2-</sup>, and the relative concentration of which is controlled by a reaction with ambient humidity and CO<sub>2</sub>. This model is able to consistently explain all our experimental findings.