julilili42/papers huggingface dataset:
Gamma-Ray Burst observation at Very High Energy with H.E.S.S.
2019-07-22

Fermi-LAT observations have proven that GeV γ-ray emission is a relatively common feature for many Gamma Ray Bursts (GRB). However the low effective area of space detectors implies low statistics for high energy photons which prevent any physical interpretation at such energy range. The current generation of Imaging Atmospheric Cherenkov Telescopes (IACTs) array of &gt; 104 m2 effective area above a few tens of GeV is able to detect higher energy photons.\\nThe High Energy Stereoscopic System (H.E.S.S.) is one of the current generation of IACTs. The large light collection area of the largest telescope and its fast slewing make it perfectly suitable to observe γ rays below 100 GeV with an unprecedented sensitivity. Several tens of GRBs have been observed since 2007. This contribution is about the results of this large sample of observation above a few tens of GeV.
Designing a clinical trial to evaluate the safety and efficacy of oral soraprazan in Stargardt Disease
2019-07-22

Purpose: To date there are no treatments available for Stargardt disease (STGD). The investigational drug soraprazan has demonstrated (in pre-clinical studies) the ability to remove lipofuscin, one of the hallmarks in STGD pathogenesis, from Retinal Pigment Epithelium (RPE) cells. Soraprazan was originally designed to treat gastro-esophageal reflux disease and successfully completed phase I and phase II clinical trials, where safety and tolerability was already demonstrated. The aim is to start a phase II trial to evaluate the efficacy of soraprazan in reducing the amount of lipofuscin in RPE cells of subjects with STGD.&lt;br/&gt;Methods: An international consortium was formed consisting of 5 investigator sites (2 in Netherlands and 1 in each of Germany, UK, and Italy), a Contract Research Organisation, and a start-up company as a sponsor (Katairo). A draft protocol and a business plan were fully costed and timelines
Long-term gamma-ray observations of the binary HESS J0632+057 with H.E.S.S., MAGIC and VERITAS
2019-07-22

The gamma-ray binary HESS J0632+057 has been observed at very-high energies (E 100 GeV) for more than ten years by the major systems of imaging atmospheric Cherenkov telescopes. We present a summary of results obtained with the H.E.S.S., MAGIC, and VERITAS experiments based on roughly 440 h of observations in total. This includes a discussion of an unusually bright TeV outburst of HESS J0632+057 in January 2018. The updated gamma-ray light curve now covers all phases of the orbital period with significant detections in almost all orbital phases. Results are discussed in context with simultaneous observations with the X-ray Telescope onboard the Neil Gehrels Swift Observatory.
Controlled illumination of a PDMS-free Retina-on-a-Chip for the proximity-culture of retinal organoids with pigment epithelial cells
2019-07-22

Purpose: In spite of comprehensive research over the last decades, there is often no treatment available for many retinal diseases, due to a lack of suitable in vitro models. We, hence, combined advanced microfabrication and stem cell technology to develop a human Retina-on-a-Chip (RoC) that embeds all relevant retinal cell types in a physiological microenvironment with vasculature-like supply. Methods: The chip-platform is fabricated using polymethylmethacrylate (PMMA) as base material. To realize a complex 3D environment within the RoC, microchannels and -structures were cut into several PMMA-layers with different heights via laser-assisted microfabrication. To separate the perfusion channels from the tissue compartments, we integrated isoporous membranes to emulate the vasculature microenvironment. The whole RoC was assembled via solvent bonding technique using defined amounts of ethanol, controlled pressure onto the layers and a convection oven. To generate the retinal tissue we combined retinal organoids and retinal pigment epithel derived from the same human induced pluripotent stem cells in the tissue compartments. Finally, for the light exposure, we developed an illumination device based on LED-arrays integrated into 3D-printed housings. Results: The developed microphysiological RoC enabled the generation of a 3D tissue featuring more than seven different cell types in a physiological multi-layer structure. Further, the RoC was able to support a stable long-term culture and to recapitulate the constant recycling process of photoreceptor outer-segments, which is a key function of the human retina. The choice of PMMA as base material provides a key advantage compared to polydimethylsiloxane (PDMS), which is commonly used for organ-on-chips (OoCs): PMMA features a much lower absorption of hydrophobic molecules. With the illumination-platform, it was possible to control the light intensity over culture periods and to apply defined exposure patterns to mimic both physiological day/night changes and light-toxicity. Conclusions: Combining the precise microengineering of OoCs with the biological self-assembly of organoids, we generated an in vitro model of the human retina with so-far unmatched functionality and the capacity for controlled light exposure. Thereby, the developed RoC is versatile for disease modeling, personalized medicine and toxicity screening. This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.
Work-break schedules for preventing musculoskeletal symptoms and disorders in healthy workers
2019-07-23

We found low-quality evidence that different work-break frequencies may have no effect on participant-reported musculoskeletal pain, discomfort and fatigue. For productivity and work performance, evidence was of very low-quality that different work-break frequencies may have a positive effect. For different types of break, there may be no effect on participant-reported musculoskeletal pain, discomfort and fatigue according to low-quality evidence. Further high-quality studies are needed to determine the effectiveness of frequency, duration and type of work-break interventions among workers, if possible, with much higher sample sizes than the studies included in the current review. Furthermore, work-break interventions should be reconsidered, taking into account worker populations other than office workers, and taking into account the possibility of combining work-break intervention with other interventions such as ergonomic training or counselling, which may may possibly have an effect on musculoskeletal outcomes and work performance.
The Novel Z-Scheme Ternary-Component Ag/AgI/α-MoO3 Catalyst with Excellent Visible-Light Photocatalytic Oxidative Desulfurization Performance for Model Fuel
2019-07-23

The novel ternary-component Ag/AgI/α-MoO3 (AAM) photocatalyst was successfully fabricated by a facile hydrothermal method combined with a charge-induced physical adsorption and photo-reduced deposition technique. X-ray diffraction, scanning/transmission electron microscope, X-ray photoelectron, UV-vis diffuse reflectance, photoluminescence and electrochemical impedance spectroscopy were employed to characterize the composition, morphology, light-harvesting properties and charge transfer character of the as-synthesized catalysts. The ternary-component AAM heterojunctions exhibited an excellent visible-light photocatalytic oxidative desulfurization activity, in which the AAM-35 (35 represents weight percent of AgI in AAM sample) possessed the highest photocatalytic activity of the conversion of 97.5% in 2 h. On the basis of band structure analysis, radical trapping experiments and electron spin resonance (ESR) spectra results, two different catalytic mechanisms were suggested to elucidate how the photogenerated electron-hole pairs can be effectively separated for the enhancement of photocatalytic performance for dual composites AM-35 and ternary composites AAM-35 during the photocatalytic oxidative desulfurization (PODS) of thiophene. This investigation demonstrates that Z-scheme Ag/AgI/α-MoO3 will be a promising candidate material for refractory sulfur aromatic pollutant’s removal in fossil fuel.
Behavioral responses to conspecific mobbing calls are predator‐specific in great tits (Parus major)
2019-07-23

Abstract When facing a predator, animals need to perform an appropriate antipredator behavior such as escaping or mobbing to prevent predation. Many bird species exhibit distinct mobbing behaviors and vocalizations once a predator has been detected. In some species, mobbing calls transmit information about predator type, size, and threat, which can be assessed by conspecifics. We recently found that great tits ( Parus major ) produce longer D calls with more elements and longer intervals between elements when confronted with a sparrowhawk, a high‐threat predator, in comparison to calls produced in front of a less‐threatening tawny owl. In the present study, we conducted a playback experiment to investigate if these differences in mobbing calls elicit different behavioral responses in adult great tits. We found tits to have a longer latency time and to keep a greater distance to the speaker when sparrowhawk mobbing calls were broadcast. This suggests that tits are capable of decoding information about predator threat in conspecific mobbing calls. We further found a tendency for males to approach faster and closer than females, which indicates that males are willing to take higher risks in a mobbing context than females.
Pigmentation of White, Brown, and Green Chicken Eggshells Analyzed by Reflectance, Transmittance, and Fluorescence Spectroscopy
2019-07-23

Abstract We report on the reflectance, transmittance and fluorescence spectra ( λ =200–1200 nm) of four types of chicken eggshells (white, brown, light green, dark green) measured in situ without pretreatment and after ablation of 20–100 μm of the outer shell regions. The color pigment protoporphyrin IX (PPIX) is embedded in the protein phase of all four shell types as highly fluorescent monomers, in the white and light green shells additionally as non‐fluorescent dimers, and in the brown and dark green shells mainly as non‐fluorescent poly‐aggregates. The green shell colors are formed from an approximately equimolar mixture of PPIX and biliverdin. The axial distribution of protein and colorpigments were evaluated from the combined reflectances of both the outer and inner shell surfaces, as well as from the transmittances. For the data generation we used the radiative transfer model in the random walk and Kubelka‐Munk approaches.
Fragmentation, rotation, and outflows in the high-mass star-forming region IRAS 23033+5951
2019-07-23

Context. The formation process of high-mass stars (&gt;8 M ⊙ ) is poorly constrained, particularly the effects of clump fragmentation creating multiple systems and the mechanism of mass accretion onto the cores. Aims. We study the fragmentation of dense gas clumps, and trace the circumstellar rotation and outflows by analyzing observations of the high-mass (~500 M ⊙ ) star-forming region IRAS 23033+5951. Methods. Using the Northern Extended Millimeter Array (NOEMA) in three configurations and the IRAM 30 m single-dish telescope at 220 GHz, we probe the gas and dust emission at an angular resolution of ~0.45′′, corresponding to 1900 au. Results. In the millimeter (mm) continuum emission, we identify a protostellar cluster with at least four mm-sources, where three of them show a significantly higher peak intensity well above a signal-to-noise ratio of 100. Hierarchical fragmentation from large to small spatial scales is discussed. Two fragments are embedded in rotating structures and drive molecular outflows, traced by 13 CO (2–1) emission. The velocity profiles across two of the cores are similar to Keplerian but are missing the highest-velocity components close to the center of rotation, which is a common phenomena from observations like these, and other rotation scenarios are not excluded entirely. Position–velocity diagrams suggest protostellar masses of ~6 and 19 M ⊙ . Rotational temperatures from fitting CH 3 CN (12 K − 11 K ) spectra are used for estimating the gas temperature and thereby also the disk stability against gravitational fragmentation, utilizing Toomre’s Q parameter. Assuming that the candidate disk is in Keplerian rotation about the central stellar object and considering different disk inclination angles, we identify only one candidate disk as being unstable against gravitational instability caused by axisymmetric perturbations. Conclusions. The dominant sources cover different evolutionary stages within the same maternal gas clump. The appearance of rotation and outflows of the cores are similar to those found in low-mass star-forming regions.
Discourse management during speech perception: A functional magnetic resonance imaging (fMRI) study
2019-07-23

Discourse structures enable us to generate expectations based upon linguistic material that has already been introduced. We investigated how the required cognitive operations such as reference processing, identification of critical items, and eventual handling of violations correlate with neuronal activity within the language network of the brain. To this end, we conducted a functional magnetic resonance imaging (fMRI) study in which we manipulated spoken discourse coherence by using presuppositions (PSPs) that either correspond or fail to correspond to items in preceding context sentences. Definite and indefinite determiners were used as PSP triggers, referring to (non-) uniqueness or (non-) existence of an item. Discourse adequacy was tested by means of a behavioral rating during fMRI. Discourse violations yielded bilateral hemodynamic activation within the inferior frontal gyrus (IFG), the inferior parietal lobe including the angular gyrus (IPL/AG), the pre-supplementary motor area (pre-SMA), and the basal ganglia (BG). These findings illuminate cognitive aspects of PSP processing: (1) a reference process requiring working memory (IFG), (2) retrieval and integration of semantic/pragmatic information (IPL/AG), (3) cognitive control of inconsistency management (pre-SMA/BG) in terms of "successful" comprehension despite PSP violations at the surface. These results provide the first fMRI evidence needed to develop a functional neuroanatomical model for context-dependent sentence comprehension based on the example of PSP processing.
Benjamini–Schramm and spectral convergence
2019-07-23

It is shown that under mild conditions, Benjamini–Schramm convergence of lattices in locally compact groups is equivalent to spectral convergence. Next both notions are extended to the relative case and then are expressed in terms of relative L^2 -theory.
Optical communications through tissue
2019-07-23

In capsule endoscopy, the wireless data transmission technologies currently employed suffer from high path loss, heavily impacting on the capsule power budget. Optical data transmission shows, in principle, scope to overcome this limitation, at least in selected tissues. Bench testing technologies, and Monte Carlo simulations on the impact of light scattering on carrier frequency, will be presented and discussed.
Intervertebral Disc Nucleus Repair: Hype or Hope?
2019-07-24

Chronic back pain is a common disability, which is often accredited to intervertebral disc degeneration. Gold standard interventions such as spinal fusion, which are mainly designed to mechanically seal the defect, frequently fail to restore the native biomechanics. Moreover, artificial implants have limited success as a repair strategy, as they do not alter the underlying disease and fail to promote tissue integration and subsequent native biomechanics. The reported high rates of spinal fusion and artificial disc implant failure have pushed intervertebral disc degeneration research in recent years towards repair strategies. Intervertebral disc repair utilizing principles of tissue engineering should theoretically be successful, overcoming the inadequacies of artificial implants. For instance, advances in the development of scaffolds aided with cells and growth factors have opened up new possibilities for repair strategies. However, none has reached the stage of clinical trials in humans. In this review, we describe the hitches encountered in the musculoskeletal field and summarize recent advances in designing tissue-engineered constructs for promoting nucleus pulposus repair. Additionally, the review focuses on the effect of biomaterial aided with cells and growth factors on achieving effective functional reparative potency, highlighting the ways to enhance the efficacy of these treatments.
XIII—The Flow of Time in Experience
2019-07-24

Abstract Our perceptual experiences as of change over time seem to be accompanied by the sense that time flows. The sense of flow is widely regarded as one of the most elusive aspects of temporal experience. In this paper, I develop a novel account of its nature. I give an initial characterization of the sense of flow as the sense that the present changes—in short, as the sense of replacement. Further, I specify the type of account of the sense of replacement to be developed: since the sense that the present changes will be assumed to be grounded in the perceptual representation that the present changes, my focus will be to explain the perceptual representation that the present changes. I develop an account of the synchronic perceptual representation of the present. Finally, I develop an account of the diachronic perceptual representation of the present as changing.
Neovagina creation methods and their potential impact on subsequent uterus transplantation: a review
2019-07-24

Congenital uterovaginal aplasia commonly occurs in Mayer–Rokitansky–Küster–Hauser syndrome. Various methods of neovagina creation exist, including nonsurgical self‐dilation, surgical dilation, and surgical procedures involving skin or intestinal transplants. Subsequent uterus transplantation is necessary to enable pregnancy. We review the main characteristics, advantages, and disadvantages of established neovagina creation methods and discuss their suitability regarding subsequent uterus transplantation. Suitability criteria include sufficient vaginal length, absence of previous major intra‐abdominal surgery, a natural vaginal axis, and a natural vaginal epithelium. In conclusion, Vecchietti‐based laparoscopically assisted neovagina creation provides ideal functional conditions for uterus transplantation. Nonsurgical self‐dilation and Wharton–Sheares–George vaginoplasty may also be suitable. Tweetable abstract This review discusses the main advantages and disadvantages of neovagina creation methods with regard to subsequent uterus transplantation.
Young magnetars with fracturing crusts as fast radio burst repeaters
2019-07-24

Abstract Fast radio bursts are millisecond-duration radio pulses of extragalactic origin. A recent statistical analysis has found that the burst energetics of the repeating source FRB 121102 follow a power law, with an exponent that is curiously consistent with the Gutenberg–Richter law for earthquakes. This hints that repeat bursters may be compact objects undergoing violent tectonic activity. For young magnetars, possessing crustal magnetic fields which are both strong (B ≳ 1015 G) and highly multipolar, Hall drift can instigate significant field rearrangements even on ≲ century long time-scales. This reconfiguration generates zones of magnetic stress throughout the outer layers of the star, potentially strong enough to facilitate frequent crustal failures. In this paper, assuming a quake scenario, we show how the crustal field evolution, which determines the resulting fracture geometries, can be tied to burst properties. Highly anisotropic stresses are generated by the rapid evolution of multipolar fields, implying that small, localized cracks can occur sporadically throughout the crust during the Hall evolution. Each of these shallow fractures may release bursts of energy, consistent in magnitude with those seen in the repeating sources FRB 121102 and FRB 180814.J0422+73.
A new three‐dimensional geometric morphometrics analysis of the Ouranopithecus macedoniensis cranium (Late Miocene, Central Macedonia, Greece)
2019-07-24

Abstract Objectives This study aims to virtually reconstruct the deformed face (XIR‐1) and maxilla (RPl‐128) of the Late Miocene hominoid Ouranopithecus macedoniensis from Greece, through the application of mirror‐imaging and segmentation. Additionally, analysis was conducted through 3D geometric morphometrics, utilizing a comparative sample of fossil hominoids, extant great apes ( Gorilla , Pan , and Pongo ) and humans, so as to explore shape variation and phenetic similarities between them. Materials and methods High‐resolution computed tomography was used to create digital representations of the XIR‐1 and RPl‐128 specimens. The virtual reconstruction of the XIR‐1 cranium was achieved by mirror‐imaging, while the RPl‐128 maxilla was virtually segmented and reattached in a correct anatomical position. Anatomical landmarks were registered in three dimensions on a comparative sample of adult crania of extant great apes, humans and fossil hominoids. The data were processed with Procrustes superimposition and analyzed using multivariate statistics methods. Results Results show that Ouranopithecus macedoniensis falls within or close to the Gorilla convex hull in the principal component analyses, and it is closer to the mean Procrustes shape distance of primarily Gorilla . Both specimens, XIR‐1 and RPl‐128, are classified as Gorilla based on discriminant function analyses. Discussion The results of our geometric morphometrics analyses indicate that Ouranopithecus macedoniensis is morphologically more similar to Gorilla than to Homo , Pan , or Pongo , results that can contribute to the evaluation of existing hypotheses about its phylogenetic position.
Relative spectral tuning of the vertical versus base modes in plasmonic nanocones
2019-07-24

Gold nanocones acting as optical antennas offer an excellent geometry for focusing light near the cone tip, acting as nano-light sources with spot sizes on the order of the tip radius. However only the vertical plasmon mode oscillating in the axial direction can effectively excite the tip, whereas lateral modes oscillating along the cone base create mostly unwanted background in applications. The present work investigates the three-dimensional plasmonic mode structure of nanocones both experimentally and numerically. By tuning the nanocone aspect ratio, the modes can be spectrally tuned relative to each other, making them coincide for maximum excitation, or tuning the base mode away from the vertical mode for effective background suppression.