bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased angiotensin II formation in the brain modulates cardiovascular homeostasis and erythropoiesis
Authors: Rodrigues André Felipe , Todiras Mihail , Qadri Fatimunnisa , Campagnole-Santos Maria Jose , Alenina Natalia , Bader Michael 
Published: May 2021

Abstract
In spite of the fact that the modulatory effects of angiotensin II (Ang II) on the sympathetic nerve activity to targeted organs involved in blood pressure (BP) regulation is well acknowledged, the local production of this peptide in the brain and the consequences of enhanced central Ang II beyond the cardiovascular system are not yet well comprehended. In the present study, we generated and validated a new transgenic mouse line overexpressing the rat full-length angiotensinogen (Agt) protein specifically in the brain (Agt-Tg). Adult Agt-Tg mice presented overall increased gene expression of total Agt in the brain including brainstem and hypothalamus. In addition, the excess of Agt led to abundantly detectable brain Ang II levels as well as increased circulating copeptin levels. Agt-Tg displayed raised BP in acute recordings, while long-term telemetrically measured basal BP was indistinguishable from wild-types. Agt-Tg has altered peripheral renin–angiotensin system and vasomotor sympathetic tone homeostasis because renal gene expression analysis, plasma Ang II measurements and ganglionic blockade experiments revealed suppressed renin expression and reduced Ang II and higher neurogenic pressure response, respectively. Plasma and urine screens revealed apparently normal fluid and electrolyte handling in Agt-Tg. Interestingly, hematological analyses showed increased hematocrit in Agt-Tg caused by enhanced erythropoiesis, which was reverted by submitting the transgenic mice to a long-term peripheral sympathectomy protocol. Collectively, our findings suggest that Agt-Tg is a valuable tool to study not only brain Ang II formation and its modulatory effects on cardiovascular homeostasis but also its role in erythropoiesis control via autonomic modulation.
Resolving the dynamical mass tension of the massive binary 9 Sagittarii
Authors: Fabry M. , Hawcroft C. , Frost A. J. , Mahy L. , Marchant P. , Le Bouquin J.-B. , Sana H. 
Published: May 2021

Context. Direct dynamical mass measurements of stars with masses above 30 M⊙ are rare. This is the result of the low yield of the upper initial mass function and the limited number of such systems in eclipsing binaries. Long-period, double-lined spectroscopic binaries that are also resolved astrometrically offer an alternative to eclipsing binaries for obtaining absolute masses of stellar objects. 9 Sgr (HD 164794) is one such long-period, high-mass binary. Unfortunately, a large amount of tension exists between its total dynamical mass inferred spectroscopically from radial velocity measurements and that from astrometric data.
Aims. Our goal is to resolve the mass tension of 9 Sgr that exists in literature, to characterize the fundamental parameters and surface abundances of both stars, and to determine the evolutionary status of the binary system, henceforth providing a reference calibration point to confront evolutionary models at high masses.
Methods. We obtained the astrometric orbit from existing and new multi-epoch VLTI/PIONIER and VLTI/GRAVITY interferometric measurements. Using archival and new spectroscopy, we performed a grid-based spectral disentangling search to constrain the semi-amplitudes of the radial velocity curves. We computed atmospheric parameters and surface abundances by adjusting FASTWIND atmosphere models and we compared our results with evolutionary tracks computed with the Bonn Evolutionary Code (BEC).
Results. Grid spectral disentangling of 9 Sgr supports the presence of a 53 M⊙ primary and a 39 M⊙ secondary, which is in excellent agreement with their observed spectral types. In combination with the size of the apparent orbit, this puts 9 Sgr at a distance of 1.31 ± 0.06 kpc. Our best-fit models reveal a large mass discrepancy between the dynamical and spectroscopic masses, which we attribute to artifacts from repeated spectral normalization before and after the disentangling process. Comparison with BEC evolutionary tracks shows the components of 9 Sgr are most likely coeval with an age of roughly 1 Myr.
Conclusions. Our analysis clears up the contradiction between mass and orbital inclination estimates reported in previous studies. We detect the presence of significant CNO-processed material at the surface of the primary, suggesting enhanced internal mixing compared to currently implemented in the BEC models. The present measurements provide a high-quality high-mass anchor to validate stellar evolution models and to test the efficiency of internal mixing processes.
A study of submillimeter methanol absorption toward PKS 1830−211:
Authors: Muller S. , Ubachs W. , Menten K. M. , Henkel C. , Kanekar N. 
Published: May 2021

Context. Methanol is an important tracer to probe physical and chemical conditions in the interstellar medium of galaxies. Methanol is also the most sensitive target molecule for probing potential space-time variations of the proton-electron mass ratio, μ, a dimensionless constant of nature.
Aims. We present an extensive study of the strongest submillimeter absorption lines of methanol (with rest frequencies between 300 and 520 GHz) in the z = 0.89 molecular absorber toward PKS 1830−211, the only high-redshift object in which methanol has been detected. Our goals are to constrain the excitation of the methanol lines and to investigate the cosmological invariance of μ based on their relative kinematics.
Methods. We observed 14 transitions of methanol, five of the A-form and nine of the E-form, and three transitions of A-13CH3OH, with ALMA. We analyzed the line profiles with a Gaussian fitting and constructed a global line profile that is able to match all observations after allowing for variations of the source covering factor, line opacity scaling, and relative bulk velocity offsets. We explore methanol excitation by running the non local thermal equilibrium radiative transfer code RADEX on a grid of kinetic temperatures and H2 volume densities.
Results. Methanol absorption is detected in only one of the two lines of sight (the southwest) to PKS 1830−211. There, the excitation analysis points to a cool (∼10 − 20 K) and dense (∼104 − 5 cm−3) methanol gas. Under these conditions, several methanol transitions become anti-inverted, with excitation temperatures below the temperature of the cosmic microwave background. In addition, we measure an abundance ratio A/E = 1.0 ± 0.1, an abundance ratio CH3OH/H2 ∼ 2 × 10−8, and a 12CH3OH/13CH3OH ratio 62 ± 3. Our analysis shows that the bulk velocities of the different transitions are primarily correlated with the observing epoch due to morphological changes in the background quasar’s emission. There is a weaker correlation between bulk velocities and the lower level energies of the transitions, which could be a signature of temperature-velocity gradients in the absorbing gas. As a result, we do not find evidence for variations of μ, and we estimate Δμ/μ=(−1.8 ± 1.2) × 10−7 at 1-σ from our multivariate linear regression.
Conclusions. We set a robust upper limit |Δμ/μ| < 3.6 × 10−7 (3σ) for the invariance of μ at a look-back time of half the present age of the Universe. Our analysis highlights that systematics need to be carefully taken into account in future radio molecular absorption studies aimed at testing Δμ/μ below the 10−7 horizon.
Dark matter capture and annihilation in stars: Impact on the red giant branch tip
Authors: Lopes José , Lopes Ilídio 
Published: May 2021

Context.While stars have often been used as laboratories to study dark matter (DM), red giant branch (RGB) stars and all the rich phenomenology they encompass have frequently been overlooked by such endeavors.Aims.We study the capture, evaporation, and annihilation of weakly interacting massive particle (WIMP) DM in low-mass RGB stars (M = 0.8−1.4 M⊙).Methods.We used a modified stellar evolution code to study the effects of DM self-annihilation on the structure and evolution of low-mass RGB stars.Results.We find that the number of DM particles that accumulate inside low-mass RGB stars is not only constant during this phase of evolution, but also mostly independent of the stellar mass and to some extent stellar metallicity. Moreover, we find that the energy injected into the stellar core due to DM annihilation can promote the conditions necessary for helium burning and thus trigger an early end of the RGB phase. The premature end of the RGB, which is most pronounced for DM particles withmχ ≃ 100 GeV, is thus achieved at a lower helium core mass, which results in a lower luminosity at the tip of the red giant branch (TRGB). Although in the current WIMP paradigm, these effects are only relevant if the number of DM particles inside the star is extremely large, we find that for light WIMPs (mχ ≃ 4 GeV), relevant deviations from the standard TRGB luminosity (∼8%) can be achieved with conditions that can be realistic in the inner parsec of the Milky Way.
The Gaia-ESO survey: Mixing processes in low-mass stars traced by lithium abundance in cluster and field stars
Authors: Magrini L. , Lagarde N. , Charbonnel C. , Franciosini E. , Randich S. , Smiljanic R. , Casali G. , Viscasillas Vázquez C. , Spina L. , Biazzo K. , Pasquini L. , Bragaglia A. , Van der Swaelmen M. , Tautvaišienė G. , Inno L. , Sanna N. , Prisinzano L. , Degl’Innocenti S. , Prada Moroni P. , Roccatagliata V. , Tognelli E. , Monaco L. , de Laverny P. , Delgado-Mena E. , Baratella M. , D’Orazi V. , Vallenari A. , Gonneau A. , Worley C. , Jiménez-Esteban F. , Jofre P. , Bensby T. , François P. , Guiglion G. , Bayo A. , Jeffries R. D. , Binks A. S. , Gilmore G. , Damiani F. , Korn A. , Pancino E. , Sacco G. G. , Hourihane A. , Morbidelli L. , Zaggia S. 
Published: May 2021

Aims. We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, IDR6, and from the Gaia Early Data Release 3, EDR3s.
Methods. We selected a sample of main-sequence, sub-giant, and giant stars in which the Li abundance is measured by the Gaia-ESO survey. These stars belong to 57 open clusters with ages from 130 Myr to about 7 Gyr and to Milky Way fields, covering a range in [Fe/H] between ∼​ − 1.0 and ∼​ + 0.5 dex, with few stars between ∼​ − 1.0 and ∼​ − 2.5 dex. We studied the behaviour of the Li abundances as a function of stellar parameters. We inferred the masses of giant stars in clusters from the main-sequence turn-off masses, and for field stars through comparison with stellar evolution models using a maximum likelihood technique. We compared the observed Li behaviour in field giant stars and in giant stars belonging to individual clusters with the predictions of a set of classical models and of models with mixing induced by rotation and thermohaline instability.
Results. The comparison with stellar evolution models confirms that classical models cannot reproduce the observed lithium abundances in the metallicity and mass regimes covered by the data. The models that include the effects of both rotation-induced mixing and thermohaline instability account for the Li abundance trends observed in our sample in all metallicity and mass ranges. The differences between the results of the classical models and of the rotation models largely differ (up to 2 dex), making lithium the best element with which to constrain stellar mixing processes in low-mass stars. We discuss the nature of a sample of Li-rich stars.
Conclusions. We demonstrate that the evolution of the surface abundance of Li in giant stars is a powerful tool for constraining theoretical stellar evolution models, allowing us to distinguish the effect of different mixing processes. For stars with well-determined masses, we find a better agreement of observed surface abundances and models with rotation-induced and thermohaline mixing. Rotation effects dominate during the main sequence and the first phases of the post-main-sequence evolution, and the thermohaline induced mixing after the bump in the luminosity function.
Das schöne, glatte Bein: Haarentfernung durch Laser und lichtbasierte Verfahren
Authors: Braun Tatjana , Kleimann Pia , Meissner Markus , Kaufmann Roland , Valesky Eva Maria 
Published: May 2021

ZusammenfassungDie Fotoepilation zählt zu den meistgefragten nichtchirurgischen Eingriffen in der ästhetischen Dermatologie. Haarlose, glatte Beine gelten dabei als Schönheitsideal.Fotoepilation mittels Laser oder hochenergetischer Blitzlampen (sog. Intensed-Pulsed-Light-Geräte) stellt ein sicheres und effektives Verfahren dar. Der Wirkmechanismus beruht auf dem Prinzip der selektiven Fotothermolyse, wobei eine gezielte thermische Schädigung pigmentierter Haarfollikel unter Schonung des umliegenden Gewebes erfolgt. Melaninpigment des Haarschaftes absorbiert als Zielchromophor Licht eines speziellen Wellenlängenspektrums und führt durch Wärmediffusion zur Schädigung der für das Haarwachstum wichtigen Stammzellen im äußeren Haarwurzelschaft.Patienten müssen über die Notwendigkeit wiederholter Behandlungen sowie den häufig nur partiellen und temporären Haarverlust aufgeklärt werden. Dunkle Terminalhaare bei hellen Hauttypen lassen sich effektiv entfernen. Bei dunklen Hauttypen besteht aufgrund des erhöhten epidermalen Melaninvorkommens ein erhöhtes Risiko für Nebenwirkungen wie Verbrennungen, Dyspigmentierungen und Narben. Sehr feine, helle oder rote Haare lassen sich kaum mit konventionellen Fotoepilationsverfahren entfernen. Haarentfernungsgeräte für den Heimgebrauch sind eine kostengünstige, einfach anzuwendende Alternative, weisen aber im Vergleich zur professionellen Fotoepilation eine geringere Effektivität auf.
Asbestos Exposure and Ovarian Cancer – a Gynaecological Occupational Disease. Background, Mandatory Notification, Practical Approach
Authors: Nowak Dennis , Schmalfeldt Barbara , Tannapfel Andrea , Mahner Sven 
Published: May 2021

AbstractIn 2017, ovarian cancer due to asbestos exposure was designated a new, and thereby the first, gynaecological occupational disease in Germany. Asbestos is a naturally occurring mineral fibre with an annual usage in Germany of 160 000 – 180 000 metric tonnes in the 1960s and 1970s. The carcinogenicity of asbestos for the target organs lungs, larynx, pleura including pericardium, and peritoneum including tunica vaginalis testis has been clearly established for many years. Recent meta-analyses of data from cohort studies have demonstrated that the risk of ovarian cancer roughly doubles in women with occupational exposure to asbestos. Since the group of people with double the risk of developing lung cancer due to work-related asbestos exposure has a 2.25-fold increased risk of mortality from ovarian cancer on average, work-related ovarian cancer has been assigned the same recognition requirements as in occupational lung (and laryngeal) cancer. Thus, gynaecologists must obtain
a thorough history of occupational exposure to asbestos, even if it may have taken place long in the past. The law mandates that suspected such cases must be reported to the Statutory Accident Insurance carrier or the State Occupational Safety and Health Agency.
„Also Stress ist jeden Tag“ – Ursachen und Bewältigung von arbeitsbedingten Fehlbelastungen im Krankenhaus aus Sicht der Beschäftigten. Eine qualitative Studie
Authors: Stiawa Maja , Peters Martin , Mulfinger Nadine , Krumm Silvia , Worringer Britta , Maatouk Imad , Küllenberg Janna , Junne Florian , Genrich Melanie , Gündel Harald , Puschner Bernd 
Published: May 2021

Zusammenfassung
Ziel der Studie Befragung von Mitarbeitern im Krankenhaus zu arbeitsbedingten Fehlbelastungen und Stressfolgen sowie Konsequenzen für Interventionen zur Stressreduktion am Arbeitsplatz.
Methodik Es wurden 6 Fokusgruppen und 7 semistrukturierte Interviews mit 34 Krankenhausmitarbeitern durchgeführt, welche inhaltsanalytisch ausgewertet wurden.
Ergebnisse Mitarbeiter berichteten von Stressfolgen durch Personalmangel, hohes Arbeitsaufkommen, fehlende Rückzugs- und Versorgungsmöglichkeiten, fehlende Absprachen, intransparente Arbeitsabläufe, Teamkonflikte und fehlende Wertschätzung. Berichtete Faktoren, die zur Reduktion von Stressfolgen führten, waren soziale Unterstützung, Arbeitszeitreduktion, Sport und Entscheidungskompetenzen.
Schlussfolgerung Interventionen zur Reduktion arbeitsbedingter Fehlbelastungen im Krankenhaus sollten sowohl berufsgruppenspezifische Interventionsangebote sowie organisationale Normen und strukturelle Rahmenbedingungen berücksichtigen.
A line-scanning chromatic confocal sensor for three-dimensional profile measurement on highly reflective materials
Authors: Hu Hao , Mei Shuang , Fan Liming , Wang Huigang 
Published: May 2021

We developed a practical Line-Scanning Chromatic Confocal Sensor (LSCCS) that can generate three-dimensional (3D) points with up to 32 000/s with a high-precision motion device. An optical route of line-scanning confocal spectroscopy is designed and verified by simulation. The LSCCS is composed of a white laser source, a chromatic confocal optics, and a self-developed spectrometer. The chromatic confocal optics consists of a slit, a chromatic lens (dispersive objective lens), and a beam splitter, and the spectrometer consists of an adjustable slit, a collimating lens, a blazed grating, a focusing lens, a CMOS, and an image processing circuit. The slit and the chromatic lens are designed for a line focus, and the polarizing beam splitter is selected to maximize the white light power collected by the CMOS. The motion device is made to realize the full-field 3D scanning. The key algorithms involved are developed to accurately restore the peak wavelength that includes the position information of the measured surface from the collected spectral image. Theoretical analysis and simulation showed that the corresponding resolutions in Z (depth), X (direction of optical fibers layout), and Y (direction of line-scanning) directions are 0.6, 10, and 5 µm, with a line length of 8 mm and a depth field of 2.4 mm. Experimental results showed that the sensor produces a measurement accuracy of 0.886 µm and a scanning speed of 90 fps. It is of great significance for the accurate measurement of the 3D profile and thickness on the highly reflective materials in the fields of optics, semiconductors, or micromechanics.
Nonparametric coalescent inference of mutation spectrum history and demography
Authors: DeWitt William S. , Harris Kameron Decker , Ragsdale Aaron P. , Harris Kelley 
Published: May 2021

SignificancePopulation histories are encoded by genomic variation among modern individuals. Population genetic inference methods, all theoretically rooted in probabilistic population models, can recover complex demographic histories from genomic variation data. However, the mutation process is treated very simply in these models—usually as a single constant. Recent empirical findings show that the mutation process is complex and dynamic over a range of evolutionary timescales and thus, deserving of richer descriptions in population genetic models. Here, we show that complex mutation spectrum histories can be accommodated by extending classical theoretical tools. We develop mathematical optimization methods and software to infer both demographic history and mutation spectrum history, revealing human mutation signatures varying through time and global divergence of mutational processes.
Effects of HTL/ETL properties on the performance of (FAPbI3)0.85(MAPbBr3)0.15 perovskite solar cells
Authors: Mashhadi Seyyed Abadi Negar , Banihashemi Mehdi , Kashani Nia Alireza 
Published: May 2021

Abstract
Mixed cation perovskite solar cells (PSCs) have shown high stability over 1000 h under outdoor conditions. In this paper, we simulated fluorine-doped tin oxide/TiO2/(FAPbI3)0.85(MAPbBr3)0.15/ Spiro-OMeTAD solar cell as the base structure by SCAPS-1D software. We then studied the effects of E
V position of hole transport layer (HTL) and E
C position of electron transport layer (ETL) and carrier density of HTL and ETL, on the performance of the solar cells. Simulation results showed that the carrier density of HTL and ETL has outstanding effect on the performance of the mixed cation PSC through band alignment between the layers. Moreover, we studied the influence of defect density of ETL/perovskite and perovskite/HTL interface layers. According to simulation results, we predict that using Spiro-OMeTAD as HTL and Nb-doped TiO2 as ETL, that have shown capability of fabrication with PSCs, improves the power conversion efficiency to 19.75%.
Performance improvement in p-Type WS2 field-effect transistors with 1T phase contacts
Authors: Yang Yafen , Li Han , Gu Zhenghao , Chen Lin , Zhu Hao , Ji Li , Sun Qingqing 
Published: May 2021

Abstract
The non-ideal contact between the metal electrode and semiconducting channel has become one of the major bottlenecks degrading the performance of field-effect transistors (FETs) based on two-dimensional (2D) materials. The formation of the Schottky barrier prohibiting the carrier injection as well as the Fermi level pinning effect have a strong impact on the device performance. In this work, we fabricated a 2D WS2 FET device with engineered metallic 1T phase at the source/drain region by using Li intercalation method. As compared to the device with conventional 2H-WS2 channel, the engineered FET with a 2H-WS2/1T-WS2 junction has exhibited greatly improved performance such as over 10 times higher carrier mobility and steeper subthreshold slope. Such results have demonstrated the boosted carrier injection into the channel over the engineered metal contact as well as the reduced tunnel barrier width between the 2H/1T-WS2 junction. This can be attractive for the large-scale integration of the 2D devices towards high-performance and high-reproducibility nanoelectronics applications.
Nano-hillock formation on CaF2 due to individual slow Au-cluster impacts
Authors: Szabo Gabriel L , Lehner Markus , Bischoff Lothar , Pilz Wolfgang , Muckenhuber Helmut , Kentsch Ulrich , Aumayr Friedrich , Klingner Nico , Wilhelm Richard A 
Published: May 2021

Abstract
We present a direct way to generate hillock-like nanostructures on CaF2(111) ionic crystals by kinetic energy deposition upon Au-cluster irradiation. In the past, the formation of similar nanostructures has been observed for both slow highly charged ions and swift heavy ions. However, in these cases, potential energy deposition of highly charged ions or the electronic energy loss of fast heavy ions, respectively, first leads to strong electronic excitation of the target material before the excitation energy is transferred to the lattice by efficient electron-phonon coupling. We now show that the kinetic energy deposited by slow single Au-clusters directly in the lattice of CaF2(111) leads to the production of nano-hillocks very similar to those found with slow highly charged and swift heavy ions, with heights between 1 and 2 nm. Our results are in good agreement with previous cluster irradiation studies regarding energy deposition and hence nano-structuring of surfaces, and we present Au-cluster irradiation as novel tool to fine-tune nanostructure formation.