bluuebunny/crossref_metadata_2025 huggingface dataset:
Fault‐tolerant cooperation for time‐varying multi‐vehicle systems with schemes
Authors: Shi Jiantao , Yang Yuhao , Sun Jun , Wang Ning
Published: July 2019

This study dealt with the fault‐tolerant cooperation problem for a class of time‐varying multi‐vehicle system with actuator faults under the mixed structure. Through solving coupled backward Riccati equations, a distributed cooperation fault‐tolerant controller was designed for satisfying the proposed constraints. Finally, a numerical simulation verified the effectiveness of the proposed method.
The super‐resolution reconstruction of SAR image based on the improved FSRCNN
Authors: Luo Zhenyu , Yu Junpeng , Liu Zhenhua
Published: July 2019

Synthetic aperture radar (SAR) images have become an important way to obtain information in the military and civilian fields, because of its unique advantages. With the development of technology and the need of application, people subjectively put forward a higher demand for image quality. Image resolution is a key factor for evaluating digital image quality and is the basis for subsequent image processing. However, the image quality of SAR images is far worse than that of optical images because of the imaging mechanism and so on. Therefore, it is more difficult to realise super‐resolution reconstruction on SAR images. In the image super‐resolution reconstruction method, a reconstruction‐based method is generally used, but the effect is poor. A method based on deep learning is used to realise the reconstruction of SAR images based on floating‐point data by obtaining the mapping relationship between low‐resolution images and high‐resolution images. At the same time, the SSIM index is introduced into the loss function, so that the reconstructed SAR image is improved both in subjective visual and in objective evaluation indicators. It lays the foundation for subsequent SAR image recognition and other work.
Joint azimuth‐range jamming for ISAR based on time delay
Authors: Botao Li , Wenfeng Dong , Yuansong Du , Peng Xu
Published: July 2019

Aiming at the problem that azimuth cosinusoidal phase‐modulation cannot be directly implemented in application, and two‐dimensional modulation can only be carried out in azimuth and distance, respectively, a joint azimuth‐range jamming method based on time delay for ISAR is proposed. The ISAR signal captured by jammer is delayed in the fast time domain. The ISAR signal captured by jammer is then delayed in the fast time domain to achieve the cosinusoidal phase‐modulation because the time delay is a function of slow time. The blind frequency shift modulation term is introduced at the same time. The simulation results show that the target will be completely submerged in the multiple jamming strips formed by the jamming signal, and the feasibility and effectiveness of the method are verified.
2D DOA estimator for coherently distributed sources using one snapshot
Authors: Lin Qingqing , Jing Meng , Shuai Ping , Huang Liangwei
Published: July 2019

A two‐dimensional (2D) direction‐of‐arrival (DOA) estimation method for coherently distributed (CD) sources has been proposed in high real‐time situation using only one snapshot. Utilising two uniform linear arrays (ULAs), the proposed algorithm first construct four equivalent matrices with rotational structures using one snapshot, and then a total equivalent covariance is extended by the four matrices. Finally, two rotational invariance matrices can been calculated by ESPRIT‐like algorithm, and the eigenvalues which contains of the information of the central DOAs can be obtained by eigen‐decomposition of the two matrices. To improve the performance of the proposed method, in‐phased accomplished data is proposed. Without snapshots accumulation, peak searching, and correlation process, the 2D DOA estimation method for CD sources can be used for real‐time situation. Several simulation results are used to illustrate the performance of the proposed method.
Discontinuity preserving phase unwrapping algorithm for simulated InSAR based on MRF model using line process
Authors: Zhou Lifan , Xia Yu
Published: July 2019

Phase unwrapping (PU) is one of the important procedures in measuring digital elevation model (DEM) from interferometric synthetic aperture radar (InSAR) images. It is known that the existence of phase discontinuity poses challenges to the traditional PU algorithms. In this study, the authors propose a coupled Markov random fields (MRF) called line process (LP) for PU, abbreviated as the LP‐MRF method. First, an 8‐neighbourhood line process is used to detect discontinuous phase surfaces while regularising continuous phase surface. Then, a truncated quadratic is utilised in the LP model for optimisation convenience. Finally, the proposed method on four types of simulated experimental data is tested, which yields that the proposed method has better performance than some of the commonly used methods in handling sharp phase discontinuities while regularising continuous phase surfaces.
Feedback from OB stars on their parent cloud: gas exhaustion rather than gas ejection
Authors: Watkins E. J. , Peretto N. , Marsh K. , Fuller G. A.
Published: July 2019

Context.Stellar feedback from high-mass stars shapes the interstellar medium, and thereby impacts gas that will form future generations of stars. However, due to our inability to track the time evolution of individual molecular clouds, quantifying the exact role of stellar feedback on their star formation history is an observationally challenging task.

Aims.In the present study, we take advantage of the unique properties of the G316.75-00.00 massive-star forming ridge to determine how stellar feedback from O-stars impacts the dynamical stability of massive filaments. The G316.75 ridge is 13.6 pc long and contains 18 900M⊙of H2gas, half of which is infrared dark and half of which infrared bright. The infrared bright part has already formed four O-type stars over the past 2 Myr, while the infrared dark part is still quiescent. Therefore, by assuming the star forming properties of the infrared dark part represent the earlier evolutionary stage of the infrared bright part, we can quantify how feedback impacts these properties by contrasting the two.

Methods.We used publicly availableHerschel/HiGAL and molecular line data to measure the ratio of kinetic to gravitational energy per-unit-length,αvirline, across the entire ridge. By using both dense (i.e. N2H+and NH3) and more diffuse (i.e.13CO) gas tracers, we were able to computeαvirlinefor a range of gas volume densities (~1 × 102–1 × 105cm−3).

Results.This study shows that despite the presence of four embedded O-stars, the ridge remains gravitationally bound (i.e.αvirline≤ 2) nearly everywhere, except for some small gas pockets near the high-mass stars. In fact,αvirlineis almost indistinguishable for both parts of the ridge. These results are at odds with most hydrodynamical simulations in which O-star-forming clouds are completely dispersed by stellar feedback within a few cloud free-fall times. However, from simple theoretical calculations, we show that such feedback inefficiency is expected in the case of high-gas-density filamentary clouds.

Conclusions.We conclude that the discrepancy between numerical simulations and the observations presented here originates from different cloud morphologies and average densities at the time when the first O-stars form. In the case of G316.75, we speculate that the ridge could arise from the aftermath of a cloud-cloud collision, and that such filamentary configuration promotes the inefficiency of stellar feedback. This does very little to the dense gas already present, but potentially prevents further gas accretion onto the ridge. These results have important implications regarding, for instance, how stellar feedback is implemented in cosmological and galaxy scale simulations.
Influence of macroclumping on type II supernova light curves
Authors: Dessart Luc , Audit Edouard
Published: July 2019

Core-collapse supernova (SN) ejecta are probably structured on both small and large scales, with greater deviations from spherical symmetry nearer the explosion site. Here, we present 2D and 3D gray radiation hydrodynamics simulations of type II SN light curves from red and blue supergiant star explosions to investigate the impact of inhomogeneities in density or composition on SN observables, with a characteristic scale set to a few percent of the local radius. Clumping is found to hasten the release of stored radiation, boosting the early time luminosity and shortening the photospheric phase. Around the photosphere, radiation leaks between the clumps where the photon mean free path is greater. Since radiation is stored uniformly in volume, a greater clumping can increase this leakage by storing more and more mass into smaller and denser clumps containing less and less radiation energy. An inhomogeneous medium in which different regions recombine at different temperatures can also impact the light curve. Clumping can thus be a source of diversity in SN brightness. Clumping may lead to a systematic underestimate of ejecta masses from light curve modeling, although a significant offset seems to require a large density contrast of a few tens between clumps and interclump medium.
Planetary system around the nearby M dwarf GJ 357 including a transiting, hot, Earth-sized planet optimal for atmospheric characterization
Authors: Luque R. , Pallé E. , Kossakowski D. , Dreizler S. , Kemmer J. , Espinoza N. , Burt J. , Anglada-Escudé G. , Béjar V. J. S. , Caballero J. A. , Collins K. A. , Collins K. I. , Cortés-Contreras M. , Díez-Alonso E. , Feng F. , Hatzes A. , Hellier C. , Henning T. , Jeffers S. V. , Kaltenegger L. , Kürster M. , Madden J. , Molaverdikhani K. , Montes D. , Narita N. , Nowak G. , Ofir A. , Oshagh M. , Parviainen H. , Quirrenbach A. , Reffert S. , Reiners A. , Rodríguez-López C. , Schlecker M. , Stock S. , Trifonov T. , Winn J. N. , Zapatero Osorio M. R. , Zechmeister M. , Amado P. J. , Anderson D. R. , Batalha N. E. , Bauer F. F. , Bluhm P. , Burke C. J. , Butler R. P. , Caldwell D. A. , Chen G. , Crane J. D. , Dragomir D. , Dressing C. D. , Dynes S. , Jenkins J. M. , Kaminski A. , Klahr H. , Kotani T. , Lafarga M. , Latham D. W. , Lewin P. , McDermott S. , Montañés-Rodríguez P. , Morales J. C. , Murgas F. , Nagel E. , Pedraz S. , Ribas I. , Ricker G. R. , Rowden P. , Seager S. , Shectman S. A. , Tamura M. , Teske J. , Twicken J. D. , Vanderspeck R. , Wang S. X. , Wohler B.
Published: July 2019

We report the detection of a transiting Earth-size planet around GJ 357, a nearby M2.5 V star, using data from the Transiting Exoplanet Survey Satellite (TESS). GJ 357 b (TOI-562.01) is a transiting, hot, Earth-sized planet (Teq = 525 ± 11 K) with a radius of Rb = 1.217 ± 0.084 R⊕ and an orbital period of Pb = 3.93 d. Precise stellar radial velocities from CARMENES and PFS, as well as archival data from HIRES, UVES, and HARPS also display a 3.93-day periodicity, confirming the planetary nature and leading to a planetary mass of Mb = 1.84 ± 0.31 M⊕. In addition to the radial velocity signal for GJ 357 b, more periodicities are present in the data indicating the presence of two further planets in the system: GJ 357 c, with a minimum mass of Mc = 3.40 ± 0.46 M⊕ in a 9.12 d orbit, and GJ 357 d, with a minimum mass of Md = 6.1 ± 1.0 M⊕ in a 55.7 d orbit inside the habitable zone. The host is relatively inactive and exhibits a photometric rotation period of Prot = 78 ± 2 d. GJ 357 b isto date the second closest transiting planet to the Sun, making it a prime target for further investigations such as transmission spectroscopy. Therefore, GJ 357 b represents one of the best terrestrial planets suitable for atmospheric characterization with the upcoming JWST and ground-based ELTs.
Cometary compositions compared with protoplanetary disk midplane chemical evolution
Authors: Eistrup Christian , Walsh Catherine , van Dishoeck Ewine F.
Published: July 2019

Context.Comets are planetesimals left over from the formation of planets in the solar system. With a growing number of observed molecular abundances in many comets, and an improved understanding of chemical evolution in protoplanetary disk midplanes, comparisons can be made between models and observations that could potentially constrain the formation histories of comets.

Aims.Our aim is to carry out the first statistical comparison between cometary volatile ice abundances and modelled evolving abundances in a protoplanetary disk midplane.

Methods.Aχ2-method was used to determine maximum likelihood surfaces for 14 different comets that formed at a given time (up to 8 Myr) and place (out to beyond the CO iceline) in the pre-solar nebula midplane. This was done using observed volatile abundances for the 14 comets and the evolution of volatile abundances from chemical modelling of disk midplanes. Two assumptions for the chemical modelling starting conditions (cloud inheritance or chemical reset), as well as two different sets of cometary molecules (parent species, with or without sulphur species) were investigated.

Results.Considering all parent species (ten molecules) in the reset scenario,χ2likelihood surfaces show a characteristic trail in the parameter space with high likelihood of formation around 30 AU at early times and 12 AU at later times for ten comets. This trail roughly traces the vicinity of the CO iceline in time.

Conclusions.A statistical comparison between observed and modelled chemical abundances in comets and comet-forming regions could be a powerful tool for constraining cometary formation histories. The formation histories for all comets were constrained to the vicinity of the CO iceline, assuming that the chemistry was partially reset early in the pre-solar nebula. This is found, both when considering carbon-, oxygen-, and sulphur-bearing molecules (ten in total), and when only considering carbon- and oxygen-bearing molecules (seven in total). Since these 14 comets did not previously fall into the same taxonomical categories together, this chemical constraint may be proposed as an alternative taxonomy for comets. Based on the most likely time for each of these comets to have formed during the disk chemical evolution, a formation time classification for the 14 comets is suggested.
Photospheric magnetic structure of coronal holes
Authors: Hofmeister Stefan J. , Utz Dominik , Heinemann Stephan G. , Veronig Astrid , Temmer Manuela
Published: July 2019

In this study, we investigate in detail the photospheric magnetic structure of 98 coronal holes using line-of-sight magnetograms of SDO/HMI, and for a subset of 42 coronal holes using HINODE/SOT G-band filtergrams. We divided the magnetic field maps into magnetic elements and quiet coronal hole regions by applying a threshold at ±25 G. We find that the number of magnetic bright points in magnetic elements is well correlated with the area of the magnetic elements (cc = 0.83 ± 0.01). Further, the magnetic flux of the individual magnetic elements inside coronal holes is related to their area by a power law with an exponent of 1.261 ± 0.004 (cc = 0.984 ± 0.001). Relating the magnetic elements to the overall structure of coronal holes, we find that on average (69 ± 8)% of the overall unbalanced magnetic flux of the coronal holes arises from long-lived magnetic elements with lifetimes > 40 h. About (22 ± 4)% of the unbalanced magnetic flux arises from a very weak background magnetic field in the quiet coronal hole regions with a mean magnetic field density of about 0.2−1.2 G. This background magnetic field is correlated to the flux of the magnetic elements with lifetimes of > 40 h (cc = 0.88 ± 0.02). The remaining flux arises from magnetic elements with lifetimes < 40 h. By relating the properties of the magnetic elements to the overall properties of the coronal holes, we find that the unbalanced magnetic flux of the coronal holes is completely determined by the total area that the long-lived magnetic elements cover (cc = 0.994 ± 0.001).
Thermal evolution and quiescent emission of transiently accreting neutron stars
Authors: Potekhin A. Y. , Chugunov A. I. , Chabrier G.
Published: July 2019

Aims.We study the long-term thermal evolution of neutron stars in soft X-ray transients (SXTs), taking the deep crustal heating into account consistently with the changes of the composition of the crust. We collect observational estimates of average accretion rates and thermal luminosities of such neutron stars and compare the theory with observations.

Methods.We performed simulations of thermal evolution of accreting neutron stars, considering the gradual replacement of the original nonaccreted crust by the reprocessed accreted matter, the neutrino and photon energy losses, and the deep crustal heating due to nuclear reactions in the accreted crust. We also tested and compared results for different modern theoretical models. We updated a compilation of the observational estimates of the thermal luminosities in quiescence and average accretion rates in the SXTs and compared the observational estimates with the theoretical results.

Results.The long-term thermal evolution of transiently accreting neutron stars is nonmonotonic. The quasi-equilibrium temperature in quiescence reaches a minimum and then increases toward the final steady state. The quasi-equilibrium thermal luminosity of a neutron star in an SXT can be substantially lower at the minimum than in the final state. This enlarges the range of possibilities for theoretical interpretation of observations of such neutron stars. The updates of the theory and observations leave the previous conclusions unchanged, namely that the direct Urca process operates in relatively cold neutron stars and that an accreted heat-blanketing envelope is likely present in relatively hot neutron stars in the SXTs in quiescence. The results of the comparison of theory with observations favor suppression of the triplet pairing type of nucleon superfluidity in the neutron-star matter.
Bias voltage effect on magnetron sputtered titanium aluminum nitride TiAlN thin films properties
Authors: Ait-Djafer Zouina Amina , Saoula Nadia , Wamwangi Daniel , Madaoui Noureddine , Aknouche Hamid
Published: July 2019

In this study, a negative substrate bias voltage is used to tune the structural, morphological, mechanical and electrochemical properties of TiAlN coatings fundamental for protective coating applications. TiAlN thin films have been deposited on glass, (001)Si and stainless steel substrates by RF magnetron sputtering at a power density of 4.41 W/cm2. The deposition rate was determined from X-ray reflectivity measurements to 7.00 ± 0.05 nm/min. TiAlN films used in this work were deposited for 60 min to yield a film thickness of 420 nm. Structural analysis has shown that TiAlN coating forms a cubic (fcc) phase with orientations in (111), (200), (220) and (222) planes. The deposited coatings present maximum hardness (H = 37.9 GPa) at −75 V. The dependence of hardness and Young's modulus and corrosion resistance on microstructure has been established. Electrochemical studies by potentiodynamic polarization in aggressive environment (3.5 wt.% NaCl) have revealed that stainless steel substrate with TiAlN coating exhibits excellent corrosion resistance.
Environmental drivers of plant assemblages: are there differences between palustrine and lacustrine wetlands? A case study from the northern Apennines (Italy)
Authors: Angiolini Claudia , Viciani Daniele , Bonari Gianmaria , Zoccola Antonio , Bottacci Alessandro , Ciampelli Paola , Gonnelli Vincenzo , Lastrucci Lorenzo
Published: July 2019

Mountain wetlands are among the most vulnerable habitats in the Mediterranean basin. Their conservation requires knowledge of plant species assemblages and their environmental drivers. In this study, we investigated what the main environmental factors driving species composition in mountain wetlands are. Differences in environmental control and floristic composition between palustrine and lacustrine wetlands were explored. We used a dataset of 168 vegetation plots (relevés), sampled at 45 mountain wetlands in the northern Apennines (central Italy). Direct ordination showed that water depth, geology type and altitude were the main factors responsible for species distribution. The most important gradient was linked to soil moisture, with hygrophilous species increasing with moisture levels. Indicator Species Analysis underlined a clear distinction in the distribution of aquatic plants between wetland subsystems. Geology and rainfall affected species assemblages in lacustrine and palustrine subsystems. Indirect ordination and Generalized Additive Models revealed that plant species and their attributes significantly changed in the wetland subsystems with an increase in hydrophytes with increasing rainfall in palustrine wetlands and a decrease in thermophilous species along an altitudinal gradient in lacustrine wetlands. Management and conservation guidelines for northern Apennines wetlands are suggested.
Spinal fusion achieves similar two-year improvement in HRQoL as total hip and total knee replacement. A prospective, multicentric and observational study
Authors: Cervera Irimia Javier , Tomé-Bermejo Félix , Piñera-Parrilla Angel R. , Benito Gallo Marina , Bisaccia Michele , Fernández-González Manuel , Villar-Pérez Julio , Fernández-Carreira Jose Manuel , Orovio de Elizaga Javier , Areta-Jiménez Francisco Javier , Álvarez Galovich Luis , Rollo Giuseppe , Caruso Luigi , Meccariello Luigi
Published: July 2019

Introduction: Total hip and knee arthroplasty (THA/TKA) are surgical procedures with proven benefits. Although the literature reports outcomes of fusion of the lumbar spine comparable to those of THA/TKA in general health-related quality-of-life (HRQoL) questionnaires, functional assessment is nevertheless needed for these results to be of use in clinical practice and management. Aim of our study was to prove that lumbar spinal fusion has similar if not better outcomes than THA/TKA using intervention-specific HRQoL questionnaires and functional assessment questionnaires.

Materials and methods: Observational, ambispective, multicentre study of three cohorts undergoing lumbar spinal fusion (n = 115), THA (n = 119) and TKA (n = 253). Patients were evaluated using the Short-Form-12 (SF-12), Harris–Hip-Score, Hospital for Special Surgery Scale (HSS) and Oswestry Low Back Pain Disability questionnaires. A minimum follow-up of two years was conducted.

Results: The SF-12 showed significant improvement in all groups. The SF-12 physical component summary score indicated a more severe pre-operative status (p = 0.031) in the THA cohort. The mental component summary score indicated a less severe pre-operative status in the TKA cohort (p = 0.008) and greater post-operative improvement in the TKA and THA cohorts across follow-up (six months p = 0.021; one year p = 0.012; two years p = 0.042). Functional assessment indicated greater pre-operative disability in the THA group. At two years of follow-up, functional improvement according to the Harris, HSS and Oswestry questionnaires were 152.01%, 50.07% and 41.14% respectively.

Conclusions: This study demonstrates that lumbar spinal fusion and total knee and hip arthroplasty are comparable in terms of functional improvement when thoroughly studied with health, quality-of-life and functional assessment questionnaires.
Jeder macht alles – das war gestern!
Authors: Hollweg Tilmann , Dimmek Bernd , Kolbe Harald Joachim , Schuchardt Stefan
Published: July 2019

In der forensischen Pflege ist die Vielfalt der Aufgaben inzwischen so groß, dass
es weder notwendig noch möglich ist, dass jeder Beschäftigte alle Tätigkeiten
ausführen kann. Deshalb plädieren unsere Autoren für eine Differenzierung von
Qualifikationsanforderungen innerhalb der forensisch-psychiatrischen Pflege.
Berichten RCT-Publikationen zur Versorgung von AMD-Patienten Baseline-Daten zum eingebrachten Patientengut mit Blick auf die Generalisierbarkeit des Studiendesigns?
Authors: Knippschild Stephanie , Krummenauer Frank , Hahn Ursula , Geis Berit , Tulka Sabrina , Baulig Christine
Published: July 2019

Hintergrund Für die Übertragbarkeit von Ergebnissen randomisierter klinischer Studien (RCTs) in den medizinischen Alltag und zur Beurteilung der methodischen Güte der Randomisierung geben die Baseline-Daten wichtige Informationen. Das CONSORT-Statement fordert dazu eine transparente Darstellung dieser Angaben. Hiermit soll die Umsetzungsrate sowie die formal korrekte Darstellung der Angaben in RCTs zur „altersbedingten Makuladegeneration“ (AMD) geprüft werden.

Material und Methode Die Grundlage für diese Untersuchung bildeten 132 RCTs (01/2004 – 12/2013), die mittels Vollerhebung durch 2 Reader parallel, unabhängig evaluiert und final konsentiert wurden. Die Bewertung der im CONSORT-Statement empfohlenen 2 Unterpunkte erfolgte hierbei hierarchisch. Bei formal korrekter Dokumentation wurde die Auffindbarkeit allgemeiner patientenbezogener Angaben wie Alter, Geschlecht, klinische Zielgröße der Untersuchung (z. B. Visus), AMD-Stadium, Vorliegen systemischer bzw. ophthalmologischer Vorerkrankungen geprüft.

Ergebnisse In 129 von 132 (98%) RCT-Publikationen konnte eine Dokumentation von Baseline-Daten aufgefunden werden, wobei 67 (51%) eine formal korrekte Umsetzung der geforderten Unterpunkte aufwiesen. Die Darstellung der Baseline-Daten bezog sich jedoch nur in 77 (58%) Studienberichten auf den Zeitpunkt „Studienbeginn“; in nur 67 (87%) Publikationen wurden Informationen für jede randomisierte Stichprobe dokumentiert.

Schlussfolgerung Das scheinbar „triviale“ Kriterium „Baseline-Daten“ erfährt auf den ersten Blick eine hohe Umsetzungsrate in Publikationen, die jedoch bei genauerer Betrachtung unvollständige Informationen aufwiesen. Im Publikationsprozess sollte auf die korrekte Umsetzung dieser grundlegenden Informationen geachtet werden.
Medikamentöse Therapieansätze für die nicht neovaskuläre AMD
Authors: Zeitz Oliver , Frentzel Dominik Pascal , Rübsam Anne , Seibel Ira , Riechardt Aline Isabel , Brockmann Claudia , Meißner Friederike , Joussen Antonia M.
Published: July 2019

Hintergrund Die nicht neovaskuläre (trockene) altersbedingte Makuladegeneration (AMD) ist bis heute nicht behandelbar. Dieser Artikel fasst die klinischen Forschungsansätze für eine medikamentöse Therapie zusammen und analysiert, warum diese nicht zum Erfolg geführt haben.

Material und Methoden Literatur und Datenbankrecherche.

Ergebnisse Insgesamt ist die Zahl der verfolgten Therapieansätze begrenzt. Nur die Reduktion von Lipofuscinablagerungen und Drusen ist spezifisch für die AMD. Weitere Ansätze sind die Modulation der Entzündung und Neuroprotektion. Derzeit konnte mit keinem der Verfahren in einer konfirmatorischen Studie das Voranschreiten der AMD gestoppt oder verlangsamt werden.

Diskussion Um die Chancen für Entwicklungserfolge zu erhöhen, muss der aktuell begrenzte pharmakologische Target Space durch die Anwendung molekularer Netzwerkanalysen erweitert werden. Da bei der trockenen AMD der Visus oft nicht der primär betroffene Parameter ist, muss flankierend die Perspektive Betroffener näher untersucht werden, um sinnvolle Therapieziele jenseits des Visus zu definieren.
Single-Center Study: Evaluating the Diagnostic Performance and Safety of Contrast-Enhanced Ultrasound (CEUS) in Pregnant Women to Assess Hepatic Lesions
Authors: Schwarze Vincent , Marschner Constantin , Negrão de Figueiredo Giovanna , Rübenthaler Johannes , Clevert Dirk-André
Published: July 2019

Background Ultrasound is an essential imaging tool for evaluating physiological and pathological fetal or maternal conditions during pregnancy. Published data is limited with respect to the application of CEUS during pregnancy. CEUS has already been safely applied for assessing uteroplacental blood flow, cesarean scar pregnancy and invasive placenta percreta. CT and MRI scans during pregnancy must be thoroughly evaluated due to harmful ionizing radiation and cerebral gadolinium deposition, respectively.

Purpose The aim of the present retrospective single-center study is to assess the diagnostic performance and safety of CEUS during pregnancy to evaluate hepatic lesions of unknown entity.

Methods 6 pregnant patients who underwent CEUS between 2005 and 2014 (mean age: 32 years; mean weeks of pregnancy: 28 weeks) were included in this study. The applied contrast agent was a second-generation blood-pool agent (SonoVue®, Bracco, Milan, Italy). CEUS examinations were performed and interpreted by a single radiologist with experience since 2000 (EFSUMB Level 3).

Results CEUS was safely performed on all included pregnant women without the occurrence of adverse fetal or maternal events. In the context of the present study, CEUS helped to safely differentiate hepatic metastases, focal nodular hyperplasia, atypical hemangioma, hepatic arteriovenous malformation and cystic echinococcosis. In two patients CEUS determined immediate therapy.

Conclusion Although not clinically approved in obstetrics so far, CEUS is a safe imaging modality which, in addition to B-mode and color Doppler ultrasonography, may be applied during pregnancy for further medical indications and to provide helpful information.
Challenges in Treating Extensive Deep Vein Thrombosis with Severe Thrombocytopenia in Patients with Antiphospholipid Syndrome—A Follow-up of 2 Years
Authors: Wei Lee Kai , Sule Ashish Anil
Published: July 2019

Thrombocytopenia is one of the most common manifestations of antiphospholipid syndrome (APS). There is little evidence or definitive guidelines regarding the treatment of APS with thrombocytopenia. We describe a patient with APS and moderate-to-severe thrombocytopenia and the challenges of balancing anticoagulation with thrombocytopenia. A 19-year-old male patient presented with right lower limb swelling to the emergency department with a history of gradually worsening right leg swelling for 1 week and was diagnosed with right leg proximal deep vein thrombosis. Ultrasound Doppler of the right lower limb revealed complete venous thrombosis from the level of the popliteal vein to the distal superficial femoral vein. Subsequently, he was found to have triple-positive APS and moderate-to-severe immune thrombocytopenia, with a platelet count nadir of 31 × 10 to the ninth power/L. He was started on anticoagulation with warfarin. The severe thrombocytopenia was not treated with immunosuppressants and the platelets fluctuated in the range of moderate-to-severe thrombocytopenia but did not develop any rethrombotic or bleeding events. His platelets varied from 31 × 10 to the ninth power/L to 106 × 10 to the ninth power/L. This case report demonstrates that it may be safe to hold off treatment for thrombocytopenia in APS, even in cases of severe thrombocytopenia. Treatment with immunosuppressants may be instituted only when platelet levels fall below 20 × 10 to the ninth power/L or when there is clinically significant bleeding, as in primary immune thrombocytopenia.
Treatment of Sinonasal Adenocarcinoma: A Population-Based Prospective Cohort Study
Authors: König Marton , Osnes Terje , Bratland Åse , Jebsen Peter , Meling Torstein R.
Published: July 2019

Objectives Sinonasal adenocarcinoma (AC) is a potentially curable disease despite being an aggressive malignancy. Long-term survival can be achieved with early diagnosis and adequate multidisciplinary treatment. Our goal was to evaluate outcomes for patients with AC treated at our institution.

Design In a population-based consecutive prospective cohort, we conducted an analysis of all patients treated for surface epithelial AC between 1995 and 2018.

Results Twenty patients were included, and follow-up was 100%. The mean follow-up time was 89 months for the entire cohort (112 months for patients with no evidence of disease). Intestinal-type AC was found in 65%, whereas nonintestinal-type AC was found in 35% of all cases; 75% had stage T3/4 disease. Tumor grade was intermediate/high in 65%. Eighteen patients underwent treatment with curative intent (craniofacial resection [CFR] in 61%, transfacial approach in 39%, adjuvant radiotherapy in 89%), achieving negative margins in 56% of cases. Overall survival (OS) rates were 90, 68, and 54% after 2, 5, and 10 years of follow-up, respectively, and the corresponding disease-specific survival (DSS) rates were 90, 73, and 58%. Age over 60 years, tumor with a maxillary origin, and microscopic bone invasion were negative prognostic factors. Radical CFR was correlated with better OS and DSS.

Conclusion The high probability of achieving radicality with CFR, the low complication rate, the acceptable toxicity of modern irradiation modalities, and the promising survival rates indicate that this strategy might be considered a safe and an effective option for treating patients with very advanced sinonasal AC.
Design and simulation of high conversion efficiency betavoltaic battery based on a stacked multilayer structure
Authors: Wu Meng , Zhang Jinwen
Published: July 2019

This paper presents the design and simulation of a high conversion efficiency betavoltaic battery composed of multiple, alternately stacked layers of silicon p-n junction converters and 63Ni isotope sources. Self-absorption of β particles within sources of different thicknesses and β particle energy deposition in the converters are investigated via Monte Carlo simulation. Optimizing the source thickness and doping concentration in the converter significantly improves the conversion efficiency and maximum output power of the proposed battery in comparison to one with a simple two-layer structure but same volume and source activity. The proposed battery can achieve an overall conversion efficiency of 3.3% and output power of 17.48 nW/mm2 from 5.05 mCi of 63Ni.
The strong Langmuir turbulence spectra in weakly relativistic plasma
Authors: He Jian-Wei , Liu Xiao-Lan , Chen Ming-Qin , Liang Liu-Feng
Published: July 2019

The spectral characteristics of strong Langmuir turbulence in weakly relativistic plasma is analyzed. The temporal evolutions of the turbulence energy density spectra are obtained by perfoyming the fast Fourier transformations on weakly relativistic Zakharov equations. The relativity parameter significantly influenced the Langmuir turbulence, in that a decrease in the relativity parameter lengthened the action time of wave-wave and wave-particle interactions, which is useful for studying the particles acceleration problem.
Fractional gray Lotka-Volterra models with application to cryptocurrencies adoption
Authors: Gatabazi P. , Mba J. C. , Pindza E.
Published: July 2019

The Fractional Gray Lotka-Volterra Model (FGLVM) is introduced and used for modeling the transaction counts of three cryptocurrencies, namely, Bitcoin, Litecoin, and Ripple. The 2-dimensional study is on Bitcoin and Litecoin, while the 3-dimensional study is on Bitcoin, Litecoin, and Ripple. Dataset from 28 April 2013 to 10 February 2018 provides forecasting values for Bitcoin and Litecoin through the 2-dimensional FGLVM study, while dataset from 7 August 2013 to 10 February 2018 provides forecasting values of Bitcoin, Litecoin, and Ripple through the 3-dimensional FGLVM study. Forecasting values of cryptocurrencies for the n-dimensional FGLVM study, n={2,3} along 100 days of study time, are displayed. The graph and Lyapunov exponents of the 2-dimensional Lotka-Volterra system using the results of FGLVM reveal that the system is a chaotic dynamical system, while the 3-dimensional Lotka-Volterra system displays parabolic patterns in spite of the chaos indicated by the Lyapunov exponents. The mean absolute percentage error indicates that 2-dimensional FGLVM has a good accuracy for the overall forecasting values of Bitcoin and a reasonable accuracy for the last 300 forecasting values of Litecoin, while the 3-dimensional FGLVM has a good accuracy for the overall forecasting values of Bitcoin and a reasonable accuracy for the last 300 forecasting values of both Litecoin and Ripple. Both 2- and 3-dimensional FGLVM analyses evoke a future constant trend in transacting Bitcoin and a future decreasing trend in transacting Litecoin and Ripple. Bitcoin will keep relatively higher transaction counts, with Litecoin transaction counts everywhere superior to that of Ripple.
Study of solar irradiation distribution in narrow channel of desiccant rotor
Authors: Li Jie , Hamamoto Yoshinori , Mori Hideo , Wang Zhan
Published: July 2019

The objective of this paper is to present experimental results on distribution characteristics of solar irradiation absorbed by the narrow channel wall of desiccant rotor. Experiments are performed with the channel made by the silica gel and the poly propylene (PP). Energy absorption rate is measured in conditions of different channel lengths, incident irradiation angles, air temperatures, and humidity. The result of the present measurement for silica gel is equal to that of the previous study [J. Li, Y. Hamamoto, and H. Mori, Transactions of the Japan Society of Refrigerating and Air Conditioning Engineers 32(2), 149–154 (2015)], which is conducted using laser light as a source. It is confirmed the previous prediction model of laser light is suitable for this solar light system. Moreover, the previous model is improved, because the rate of laser for PP is larger than that of solar. These models are applicable to predict desorption rate of the water vapor in a desiccant rotor heated directly by the concentrated solar irradiation. The results show that the absorption rates of solar irradiation and red laser are equal to each other in the silica gel channel. The absorption rates of the laser irradiation are larger than that of the solar irradiation for PP materials. It is clear that the solar irradiation absorption rate cannot be influenced by the ambient humidity and temperature. The prediction model of the absorption efficiency based on the laser for silica gel channel can reproduce well the absorption efficiency of experiment based on solar irradiation. In the case of PP, the difference between the prediction and the measurement is observed.
Atomistic design favored compositions and atomic-level structure of Mg–Ca–Ag ternary metallic glasses
Authors: Chen Fengjiao , Cheng Songqi , Liu Jian-bo , Li Jiahao , Zhao Shuai , Li Shunning , Yang Qilin , Liu Baixin
Published: July 2019

A realistic interatomic potential of Mg–Ca–Ag system is constructed under a proposed modified tight-binding scheme with the aid of ab initio calculations. Then, the favored and optimized compositions for forming Mg–Ca–Ag metallic glasses are investigated by means of the potential-based molecular dynamics simulations of atomistic modeling. The calculation shows that the Mg–Ca–Ag ternary system is liable to form amorphous alloys and the favored compositions for metallic glass formation locate at a sub-region, where the amorphization driving force is greater than that of other regions. Notably, we improve the conventional method of removing the facets in the amorphous structure analysis, and we introduce K-means clustering to eliminate the facets of the Voronoi polyhedra, which allows more reasonable description of various geometries of the different central atoms and their neighboring atoms. Then, both the Voronoi tessellation method and the Honeycutt–Andersen pair analysis are used to describe the disordered structure in Mg50Ca30Ag20 metallic glass based on the result of K-means clustering. Our work provides good guidance for composing the Mg–Ca–Ag metallic glasses, and further verifies the microstructure of the amorphous alloys.
Tunable optical meta-surface using graphene-coated spherical nanoparticles
Authors: Raad Shiva Hayati , Atlasbaf Zahra
Published: July 2019

Graphene-coated spherical nanoparticles are proposed as the unit cells of a single negative (SNG) meta-surface at infrared frequencies. To derive the effective permittivity of the meta-surface, each graphene layer is represented as a thin shell with complex conductivity calculated by the Kubo formulas. Later, based on the modified Mie Lorenz coefficients of the particle, electric polarizability of the unit cell is obtained, to be used in the Clausius–Mossotti effective medium formulation. The proposed structure has lower optical losses in comparison to its noble metal counterparts and it is tunable by varying the bias voltages of graphene shells. Moreover, material and geometrical parameters of the particles along with the filling fraction of the meta-surface are other parameters for the control of the optical response in the target frequency. A deep sub-wavelength tunable perfect reflector is considered as an instance. Two possible applications of the designed reflector are in lenses and semiconductor laser cavities, as a promising replacement to Bragg reflectors.
Promote efficiency of harvesting vibration energy by tailoring potential energy with addition of magnets
Authors: Pan Jianan , Qin Weiyang , Deng Wangzheng
Published: July 2019

Large-amplitude snap-through motion might happen between two equilibria of a buckling inverted piezoelectric beam under vibration excitation, therefore enhancing the energy harvesting performance of system significantly. However, in practical application, owing to the deep potential well of a buckling beam, relatively large excitation amplitude is needed to trigger such snap-through motion. To overcome this limitation, we herein propose an improved inverted beam harvester that comprises an inverted beam with an affixed tip magnet and two additional magnets mounted in the vicinity of the equilibrium positions. By introducing this repulsive magnetic force, the potential energy could be tailored to promote the occurrence of snap-through motion. Numerical simulation is conducted and it is shown that with the proposed design the harvester would be able to realize snap-through motion more easily compared to the original buckling system. This has also been validated by the experiment in which large deflection and voltage output are both observed when snap-through motion is activated under low excitation frequency.
New variational calculus equation calculates space-charge limited current for any geometry
Authors: Frank Jodi Ackerman
Published: July 2019

Rather than directly solving Poisson’s equation, researchers apply variational calculus to calculate space charge limited emission current density for cylindrical and spherical geometries and beyond.
Parochialism, social norms, and discrimination against immigrants
Authors: Choi Donghyun Danny , Poertner Mathias , Sambanis Nicholas
Published: July 2019

Significance

As immigration increases due to globalization, wars, and climate change, there is more interaction between native and immigrant populations and more potential for conflict. Policymakers have emphasized the need to better integrate immigrants to forge a common set of norms concerning appropriate behavior. However, there is a lack of evidence to support the hypothesis that a shared understanding of norms can reduce discrimination. We provide experimental evidence that religious differences cause bias and discrimination in everyday interactions between natives and immigrants. Cultural integration signaled through immigrants’ enforcement of local norms reduces, but does not eliminate, bias. As long as public debates and policies heighten the importance of religious differences, cultural integration will not be able to eliminate intergroup conflict.
A thylakoid membrane-bound and redox-active rubredoxin (RBD1) functions in de novo assembly and repair of photosystem II
Authors: García-Cerdán José G. , Furst Ariel L. , McDonald Kent L. , Schünemann Danja , Francis Matthew B. , Niyogi Krishna K.
Published: July 2019

Significance

Photosystem II (PSII) catalyzes the light-driven oxidation of water in photosynthesis, supplying energy and oxygen to many life-forms on earth. During PSII assembly and repair, PSII intermediate complexes are prone to photooxidative damage, requiring mechanisms to minimize this damage. Here, we report the functional characterization of RBD1, a PSII assembly factor that interacts with PSII intermediate complexes to ensure their functional assembly and repair. We propose that the redox activity of RBD1 participates together with the cytochrome
b
559
to protect PSII from photooxidation. This work not only improves our understanding of cellular protection mechanisms for the vital PSII complex but also informs genetic engineering strategies for protection of PSII repair to increase agricultural productivity.
The use of Off-Label Medications in Substance Abuse Treatment Programs
Authors: Paino Maria , Aletraris Lydia , Roman Paul M.
Published: July 2019

Background: Substance use disorder (SUD) treatment centers serve a population of clients who have diverse needs, and may desire or require access to varied treatments while seeking care for their SUDs. While pharmacotherapies have increased in popularity for the treatment of SUDs, adoption rates do remain quite low. But a wider array of pharmacotherapies has become available in recent years which may shift the trend. This article helps shed light on how variations in SUD treatment centers develop and persist with regard to the adoption and delivery of off-label medications.

Methods: We use a nationally representative and longitudinal sample of SUD treatment centers in the US ( N = 196). We use a logistic regression to analyze the relationship between organizational characteristics and offering any medications, off-label. We also use a negative binomial regression to analyze the relationship between organizational characteristics and the number of medications that were used off-label.

Results: Our findings reveal that older centers, accredited centers, and centers that offer mental health screenings are all positively associated with the provision of off-label medication in SUD treatment. We also find a positive relationship between private funding and offering a greater number of off-label medications.

Conclusions: Our results suggest that SUD clients who seek treatment from centers that offer medications off-label, may have access to a greater number of medication-assisted treatment options.
Article Commentary: Opioid Discontinuation as An Institutional Mandate: Questions and Answers on Why We Wrote to the Centers for Disease Control and Prevention
Authors: Kertesz Stefan G. , Satel Sally L. , DeMicco James , Dart Richard C. , Alford Daniel P.
Published: July 2019

On March 6, 2019, a self-designated committee sent a public letter to the Centers for Disease Control and Prevention (CDC) urging the agency to address the widespread misapplication of its 2016 guideline on prescribing opioids. Three hundred and eighteen health care professionals, and three former Directors of the White House Office of National Drug Control Policy (Drug Czars) signed the letter, as did the parent organization for Substance Abuse Journal, the Association for Multidisciplinary Education and Research on Substance use and Addiction. The letter reflected concern about a wide range of initiatives and policies by payers, quality metric agencies, health care organizations, and other regulators enforced to strongly incentivize or mandate forced opioid dose reductions on long-term opioid recipients who were otherwise stable. In April of 2019, both the United States Food and Drug Administration and the CDC's Director issued statements that could help to reduce ongoing harms resulting from such forced reductions, provided they are taken seriously. This commentary explains the rationale for the original letter, and the optimum course of action now that the CDC has responded.