bluuebunny/crossref_metadata_2025 huggingface dataset:
HCl–H2O dimer: an accurate full-dimensional potential energy surface and fully coupled quantum calculations of intra- and intermolecular vibrational states and frequency shifts
Authors: Liu Yang , Li Jun , Felker Peter M. , Bačić Zlatko
Published: March 2021

The present work reports a new full-dimensional potential energy surface (PES) of the HCl–H2O dimer, and the first fully coupled 9D quantum calculations of the intra- and intermolecular vibrational states of the complex, utilizing this PES.
Fundamental studies to emerging applications of pyrrole-BF2 (BOPHY) fluorophores
Authors: Bismillah Aisha N. , Aprahamian Ivan
Published: March 2021

This review highlights the up-and-coming pyrrole-BF2 (BOPHY) fluorophores, with a focus on synthetic procedures, photophysical properties – including structure–property analyses – as well as emerging applications.
Thermodynamics and kinetics analyses of high CO2 absorption properties of Li3NaSiO4 under various CO2 partial pressures
Authors: Hirai Manami , Niwa Eiki , Hashimoto Takuya
Published: March 2021

The temperature and P(CO2) region for the reaction between Li3NaSiO4 and CO2 is similar to that of Li4SiO4. However, Li3NaSiO4 shows higher CO2 absorption kinetics.
Recent advances in organophosphorus–chalcogen and organophosphorus–pincer based macrocyclic compounds and their metal complexes
Authors: Mondal Dipanjan , Balakrishna Maravanji S.
Published: March 2021

This short review describes the recent developments in organophosphorus–chalcogen and organophosphorus–pincer macrocycles and their metal complexes with emphasis on synthetic methodologies.
Enhanced electrocatalytic oxygen reduction reaction for Fe–N4–C by the incorporation of Co nanoparticles
Authors: Jiang Tao , Luan Weiling , Turyanska Lyudmila , Feng Qi
Published: March 2021

Co@Fe–N–C with the incorporation of Co nanoparticles on the surface of Fe–N4–C is prepared using a novel assisted thermal loading method which shows greatly enhanced ORR activity when compared to Fe–N–C.
A membrane-less electrolyzer with porous walls for high throughput and pure hydrogen production
Authors: Hadikhani Pooria , Hashemi S. Mohammad H. , Schenk Steven A. , Psaltis Demetri
Published: March 2021

The porous wall electrolyzer utilizes two porous walls between nucleation sites in order to achieve high hydrogen production rates with high purity.
Low-operating temperature ammonia sensor based on Cu2O nanoparticles decorated with p-type MoS2nanosheets
Authors: Ding Yanqiao , Guo Xuezheng , Du Bingsheng , Hu Xiaofei , Yang Xi , He Yong , Zhou Yong , Zang Zhigang
Published: March 2021

Cu2O/MoS2hybrids are used for the low-operating temperature detection of NH3. A sensing response of 872% is achieved for the M-5 sensor, displaying an improvement compared with bare Cu2O (103%). The selectivity is also increased for M-5 sensor.
SOX7 suppresses endothelial-to-mesenchymal transitions by enhancing VE-cadherin expression during outflow tract development
Authors: Jiang Xuechao , Li Tingting , Li Bojian , Wei Wei , Li Fen , Chen Sun , Xu Rang , Sun Kun
Published: March 2021

The endothelial-to-mesenchymal transition (EndMT) is a critical process that occurs during the development of the outflow tract (OFT). Malformations of the OFT can lead to the occurrence of conotruncal defect (CTD). SOX7 duplication has been reported in patients with congenital CTD, but its specific role in OFT development remains poorly understood. To decipher this, histological analysis showed that SRY-related HMG-box 7 (SOX7) was regionally expressed in the endocardial endothelial cells and in the mesenchymal cells of the OFT, where EndMT occurs. Experiments, using in vitro collagen gel culture system, revealed that SOX7 was a negative regulator of EndMT that inhibited endocardial cell (EC) migration and resulted in decreased number of mesenchymal cells. Forced expression of SOX7 in endothelial cells blocked further migration and improved the expression of the adhesion protein vascular endothelial (VE)-cadherin (VE-cadherin). Moreover, a VE-cadherin knockdown could partly reverse the SOX7-mediated repression of cell migration. Luciferase and electrophoretic mobility shift assay (EMSA) demonstrated that SOX7 up-regulated VE-cadherin by directly binding to the gene’s promoter in endothelial cells. The coding exons and splicing regions of the SOX7 gene were also scanned in the 536 sporadic CTD patients and in 300 unaffected controls, which revealed four heterozygous SOX7 mutations. Luciferase assays revealed that two SOX7 variants weakened the transactivation of the VE-cadherin promoter. In conclusion, SOX7 inhibited EndMT during OFT development by directly up-regulating the endothelial-specific adhesion molecule VE-cadherin. SOX7 mutations can lead to impaired EndMT by regulating VE-cadherin, which may give rise to the molecular mechanisms associated with SOX7 in CTD pathogenesis.
Joint active and passive beamforming optimization for intelligent reflecting surface assisted proactive eavesdropping
Authors: Yang Jie , Huang Kaizhi , Sun Xiaoli , Wang Yi
Published: March 2021

This paper investigates a three‐node proactive eavesdropping system with the aid of intelligent reflecting surface (IRS), where a monitor tries to wiretap information and transmit jamming signals simultaneously to interfere with the suspicious link. The IRS is deployed around the suspicious users to reconstruct propagation channel. Meanwhile, with large low‐cost passive reflecting elements, it can provide more spatial degrees of freedom to moderate the link quality. In order to degrade exposure risk of eavesdropping behavior, the authors' objective is to minimize the jamming power by carefully designing jamming beamforming vectors and the phase shifts under the constraint of reliable intercepted information. The formulated problem is non‐trivial to solve due to the coupling variables and unit‐modulus constraints. Fortunately, by using alternating optimization and successive convex approximation techniques, the original problem is transformed into convex form and a sub‐optimal solution is achieved. Numerical results show that the proposed scheme can effectively reduce the jamming power and the number of the jamming antennas over benchmark schemes, which is quite suitable for covertly overhearing signal.
Multi‐vendor interoperability in HVDC grid protection: State‐of‐the‐art and challenges ahead
Authors: Wang Mian , Leterme Willem , Chaffey Geraint , Beerten Jef , Van Hertem Dirk
Published: March 2021

Multi‐vendor interoperable HVDC grid protection is key to build large‐scale HVDC grids in a step‐by‐step manner. On the one hand, various protection strategies and technologies have been developed in the past decade to address the challenges associated with HVDC grid protection. On the other hand, state‐of‐the‐art HVDC technologies are often vendor‐specific and there is a general lack of standardisation on HVDC systems as the majority of existing HVDC systems have been built by single vendors as turn‐key projects. In recent years, driven by the need to develop multi‐vendor HVDC grids, both national and international standardisation bodies have been working on guidelines and pre‐standardisation for HVDC systems. This paper provides a comprehensive review of the recent progress on HVDC grid protection focusing on multi‐vendor interoperability and identifies the main challenges to achieve interoperable HVDC grid protection. Compared to AC system protection, the fundamental differences of multi‐vendor interoperability in HVDC grid protection are the possible co‐existence of multiple protection philosophies and the extended scope of the fault clearing process in terms of protection and control. The challenges and research needs related to multi‐vendor HVDC grid protection due to these fundamental differences are identified.
Features of teaching swimming to children of primary school age with autism spectrum disorder
Authors: Shayakhmetova E. Sh. , Matveeva L. M. , Sitdikova A. A. , Sokolova V. A.
Published: March 2021

The article presents an analysis of the peculiarities of teaching swimming to children of primary school age with autism spectrum disorder. The study was conducted on the basis of the sports complex “Burevestnik” in Kazan. According to the results of testing on the scale of assessment of the degree of autism of children, a group of boys aged 9-10 years was formed. In four children, the degree of autism is not expressed and moderately pronounced, in one child-a severe form of autism. At the time of the examination, the children did not know how to swim. Classes on the water were held for six months 3 times a week for 40 minutes. The children trained using the author’s equipment – special boards with an associative character (a fish with bubbles, a whale with a fountain, a dolphin, a frog, a turtle, a rocket). The size of the swimming board remained standard, 32x25cm. The development of the supporting device was due to the need to eliminate the inadequate response to various sensory stimuli, such as touching strangers or tactile contact with unfamiliar objects and textures, as well as to obtain positive associations and mental images for the successful development of a new exercise. At the end of six months of classes, all children with autism spectrum disorder have mastered swimming training according to the indicators: 1) immersion in water with exhalation in water, 2) sliding on the chest with the movement of the legs, 3) sliding on the chest with the movement of the legs and performing proper breathing. The study was determined by the ability to use boards to swim copyright form associative nature.
On the choice issue of functional tests in physical fitness of the undergraduates
Authors: Talantseva Valentina , Orlov Andrei , Altynova Nadezhda , Platunov Andrei
Published: March 2021

Purpose: The purpose of our research is to determine, on the basis of mathematical processing of the experimental results, the most informative functional test, which makes it possible with a greater degree of reliability to assess the state of the vestibular apparatus and the presence of deviations in the work of the nervous system of students of higher educational institutions, and thereby recommend it for use in the practice of physical education in higher educational institutions. Results: Data analysis of the ascertaining experiment for evaluation of the condition of the vestibular system and possible nervous system disorder of the undergraduates shows a significant difference in functional test indicators which makes it necessary to choose the most informative one. Considering the comparison of the test results according to the normal distribution law and further calculation of variation coefficient of the received data it was defined that Romberg test example assuming to hold the balance standing on one leg with eyes closed with hands upwards is the most informative test allowing to more exactly define the condition of the vestibular system and nervous system of the undergraduates. Conclusion: Practical application of functional tests in physical training of students and interpretation of received data regarding the actual biological age of students allows us to actualize their need in physical activity increase. Herewith it is necessary to rely on results of the most informative functional tests, which do not require the application of complex measuring equipment and are quite simple in calculation of results.
Neural Network Algorithms and Methods for Monitoring the Psychological State of Society During Epidemics
Authors: Rogachev Aleksey , Mazaeva Tamara
Published: March 2021

The article presents the issue of monitoring the sociopsychological state of society in the period of epidemics by means of neural network algorithms and methods. Publications of sociologists, psychologists, and philologists, who have created a number of methods for in-depth analysis of emotions and tonality of texts in the Internet media, including cognitive and interpretive decoding, are devoted to substantiating approaches and methods for studying the content of Internet content. The purpose of the study is to substantiate the methods and computer tools for studying the socio-psychological state of society in crisis situations, in particular epidemics, based on neural network technologies based on Internet resources. The article considers methodological approaches and particular methods of their computer implementation. It is shown that for the computer analysis of the psychological state of society in the context of the epidemic, it is necessary to adapt the methodology for designing neural network technologies, as well as systems for collecting and textual analysis of the content of electronic and Internet resources. An effective approach to creating such systems is embedding, which uses a dense vector representation of tokens in a multidimensional space, the dimension of which should be selected experimentally in the process of training and testing the developed artificial neural networks (ANN). For contextual neural network analysis, a multiclass-oriented ANN with regularization layers of the form “SpatialDropout1D”can be used. The neural network architecture can be built on fully connected layers with an activation function of the “ReLU” type. The scientific and applied significance of the results of neural network analysis based on Internet resources is the possibility of obtaining classified assessments and segmentation of target information about the psychological state of society during periods of epidemics. This information can be used to effectively counter information threats to society.
Impact Investing in Sports and Healthcare: problems and trends in measurement
Authors: Dedusenko Elena
Published: March 2021

The idea of this paper is to focus on the trends of the impact investing industry worldwide. At this stage of the impact investing development in the international scale such researches are crucial steps for its further growth and use in the different industries. It is essential aim to analyse impact investing potential in the sports and healthcare sectors. In addition, an interesting area of research is the comparison of metrics for evaluating the effectiveness of impact investing and sports and healthcare. The key issues studied include the actual trends and challenges in impact investing system and recommendations for improvement of the impact investing ecosystem.
Anthropogenic temperversusgeological and pedological inclusions: grog temper as a possible chrono-cultural marker for the Late Ceramic Age in the pre-Columbian Lesser Antilles
Authors: Fronteau Gilles , van den Bel Martijn
Published: March 2021

In order to compare pre-Columbian cultural affiliations in the Lesser Antilles, we studied three ceramic series from Guadeloupe (F.W.I.) from well-dated Troumassoid sites between AD 1000 and 1300 (radiometric ages) attributed to the Late Ceramic Age (AD 1000–1500). The significance of the different types of inclusions in these ceramics is discussed through a petrographic study using optical and electron microscopy, that we subsequently compared with the local geological contexts. Two of the studied sites are located in the volcanic part of Guadeloupe (Basse-Terre), while the third one is situated in an area dominated by the sedimentary substratum of Grande-Terre and its silty cover. The petrographic analysis shows either the use of local heterogeneous materials: natural, geological or pedological aplastic inclusions (volcanic sands and cinders, ferruginous soils), and the addition of grog (anthropogenic temper). At each of the three sites studied, the presence of grog was demonstrated for several modal series. Comparison of the compositions of the pastes with the ceramic chrono-typology allow us to explore the proposition presented by Donahueet al.(1990), suggesting that the use of grog may infer a difference between Troumassoid and pre-Troumassoid assemblages. We also hypothesize a progressive diffusion of the use of grog temper into the Lesser Antilles, from the Guianas. This idea defies the commonly accepted idea that Troumassoid developed smoothly out of a locally present Saladoid ceramic series without external influence.
Seaweeds in viticulture: a review focused on grape quality
Authors: Gutiérrez-Gamboa Gastón , Moreno-Simunovic Yerko
Published: March 2021

Cell walls of seaweeds contain a wide number of organic and inorganic constituents, of which polysaccharides have important biological activity. Some researchers suggest that polysaccharides from seaweeds can behave as biotic elicitors in viticulture, triggering the synthesis of phenolic compounds in leaves and grape berries. The mechanism of action of seaweeds after a foliar application to grapevines is not fully understood but it is discussed in this review. An overview of the recent research focused on the effects of seaweeds foliar applications on grapevine productivity, on grape and wine quality is included as well as a short-term future perspective for the research in this field.
Various choices of source terms for a class of two-fluid two-velocity models
Authors: Hurisse Olivier
Published: March 2021

The source terms of the Baer–Nunziato model involve highly non-linear return to equilibrium terms. In order to perform numerical simulations of realistic situations, accounting for this relaxation effects is mandatory. Unfortunately, with the classical forms retained for these source terms in the literature, building efficient, robust and accurate numerical schemes is a tricky task. In this paper, we propose different non-classical forms for these source terms. As for the classical ones, they all agree with the second law of thermodynamics and they are thus associated with a growth of an entropy. The great advantage of some of these new forms of source terms is that they are more linear with respect to the conservative variables. Consequently, this allows to propose more robust, efficient and accurate numerical schemes, in particular when considering fractional step approaches for which source terms and convection terms are solved separately.
Effects and Side Effects of Platelet Transfusion
Authors: Cognasse Fabrice , Hally Kathryn , Fauteux-Daniel Sebastien , Eyraud Marie-Ange , Arthaud Charles-Antoine , Fagan Jocelyne , Mismetti Patrick , Hamzeh-Cognasse Hind , Laradi Sandrine , Garraud Olivier , Larsen Peter
Published: March 2021

Aside from their canonical role in hemostasis, it is increasingly recognized that platelets have inflammatory functions and can regulate both adaptive and innate immune responses. The main topic this review aims to cover is the proinflammatory effects and side effects of platelet transfusion. Platelets prepared for transfusion are subject to stress injury upon collection, preparation, and storage. With these types of stress, they undergo morphologic, metabolic, and functional modulations which are likely to induce platelet activation and the release of biological response modifiers (BRMs). As a consequence, platelet concentrates (PCs) accumulate BRMs during processing and storage, and these BRMs are ultimately transfused alongside platelets. It has been shown that BRMs present in PCs can induce immune responses and posttransfusion reactions in the transfusion recipient. Several recent reports within the transfusion literature have investigated the concept of platelets as immune cells. Nevertheless, current and future investigations will face the challenge of encompassing the immunological role of platelets in the scope of transfusion.
Demonstration of a laser-driven, narrow spectral bandwidth x-ray source for collective x-ray scattering experiments
Authors: MacDonald M. J. , Saunders A. M. , Bachmann B. , Bethkenhagen M. , Divol L. , Doyle M. D. , Fletcher L. B. , Glenzer S. H. , Kraus D. , Landen O. L. , LeFevre H. J. , Klein S. R. , Neumayer P. , Redmer R. , Schörner M. , Whiting N. , Falcone R. W. , Döppner T.
Published: March 2021

X-ray Thomson scattering (XRTS) is a powerful diagnostic technique that involves an x-ray source interacting with a dense plasma sample, resulting in a spectrum of elastically and inelastically scattered x-rays. Depending on the plasma conditions, one can measure a range of parameters from the resulting spectrum, including plasma temperature, electron density, and ionization state. To achieve sensitivity to collective electron oscillations, XRTS measurements require limited momentum transfer where the spectral separation of elastic and inelastic scattering is small. Such measurements require an x-ray probe source with a narrow bandwidth in order to reduce the spectral overlap between scattering contributions, allowing for the different features to be more precisely deconvolved. In this investigation, we discuss the theory behind how the bandwidth for a common XRTS probe, Zn He-α emission at 9 keV, can be reduced using a Cu K-edge filter. Proof-of-principle experiments conducted at the OMEGA laser facility confirm that this is an effective method for attenuating the higher energy He-α peak in the Zn emission spectrum. Calibration measurements at the National Ignition Facility show a reduction in spectral bandwidth from 87 eV to 48 eV when using the Cu filter, which will be important to improve the spectral resolution of future XRTS measurements that will probe plasmon oscillations in strongly compressed plasmas of low-Z materials at densities of tens of g/cm3.
A mV-level real-time peak-voltage detection circuit based on differential structure
Authors: Wu Qing , Wang Shiliang , Liao Congwei , Tang Zhexiang , Luo Heng , Huang Shengxiang , Deng Lianwen
Published: March 2021

A peak-voltage detection circuit based on a differential comparison structure is proposed to synchronize the control and the input signal. The detection circuit is hence free of reset signals for the sampling capacitors. Furthermore, a two-channel parallel sample and hold structure (i.e., S/H circuit) is used, and a correlated double sampling technique is used, in combination with the ping-pong technique, to sample the signal value and offset voltage within one sample cycle. Consequently, the parallel connected S/H structure can not only extract the offset voltage of the op-amp but also effectively reduce the detection error, which is caused by circuit noise and leakage current. Measurements of the implemented peak detector show that in the case that the detection signal frequency is 20 kHz and the amplitude is 10 mV, the detection error is decreased to 30 µV with the equivalent output noise of 71 nV/Hz.
A Fock space coupled cluster based probing of the single- and double-ionization profiles for the poly-cyclic aromatic hydrocarbons and conjugated polyenes
Authors: Chaudhuri Rajat K. , Chattopadhyay Sudip
Published: March 2021

Sequential formation of a poly-cyclic aromatic hydrocarbon (PAH) dication in the H I regions of the interstellar medium (ISM) is proposed to be a function of internal energy of the doubly ionized PAHs, which, in turn, is dependent on the single- and double-ionization potentials of the system. This sets a limit on the single- and double-ionization energies of the system(s) that can further undergo sequential absorption of two photons, leading to a dication (PAH+2). Here, we report the single-ionization (I+1) and double-ionization (I+2) energies and the I+2/I+1 ratio for some selected PAHs and conjugated polyenes obtained using the Fock space coupled cluster technique, enabling simultaneous consideration of several electronic states of different characters. The I+2 to I+1 ratio bears a constant ratio, giving allowance to determine I+2 from the knowledge of single-ionization (I+1) and vice versa. Our observations are in good agreement with the established literature findings, confirming the reliability of our estimates. The measured single- and double-ionization energies further demonstrate that the sequential formation and fragmentation of a PAH dication in the H I regions of the ISM for systems such as benzene and conjugated polyenes such as ethylene and butadiene are quite unlikely because I+2–I+1 for such system(s) is higher than the available photon energy in the H I regions of the ISM. Present findings may be useful to understand the formation and underlying decay mechanisms of multiply charged ions from PAHs and related compounds that may accentuate the exploration of the phenomenon of high-temperature superconductivity.
Nonlinear effects in locally resonant nanostrip phononic metasurface at GHz frequencies
Authors: Gao Feng , Bermak Amine , Benchabane Sarah , Raschetti Marina , Khelif Abdelkrim
Published: March 2021

In this paper, we report on the observation of nonlinear effects in a nanostrip phononic metasurface (NPM) that enable the tuning of resonance frequencies at 1.42 GHz. The NPM resonator made of a periodic nanostrip array is fabricated on a lithium niobate substrate. Each of the nanostrips is 250 nm wide and is made of a 680-nm-thick SiO2 layer stacking on 50-nm Al metal electrodes. Finite element analysis reveals that the device operates in a vertically polarized (compression) mode with substantial acoustic energy confined in the nanostrips, leading to a local resonance at low acoustic velocity. Due to the nonlinearity, the resonance frequency of the device decreases with the increase in stimulation power. The underlying mechanism of the nonlinearity is found to be the power-dependent coupling of the adjacent nanostrips. This coupling induces softening of the substrate surface region, which reduces the acoustic velocity and, hence, the bulk radiation. As a result, the quality factor of the NPM resonator is found to improve with the increase in stimulation power. The power-dependent coupling of nanostrips in the NPM resonator demonstrates a reliable method for the realization of nonlinearity in phononic metasurfaces, which would significantly enrich the mechanisms for the manipulation of surface acoustic waves at high frequencies.
Supercurrent-controlled kinetic inductance superconducting memory element
Authors: Ilin Eduard , Song Xiangyu , Burkova Irina , Silge Andrew , Guo Ziang , Ilin Konstantin , Bezryadin Alexey
Published: March 2021

We report a superconducting kinetic inductance memory (SKIM) element, which can be controlled exclusively by the bias supercurrent, without involving magnetic fields and heating elements. The SKIM is nonvolatile memory. The device is made of two Nb Dayem bridges, and it can operate reliably up to 2.8 K. The achieved error rate is as low as one in 105 operations.
A first-principles understanding of point defects and impurities in GaN
Authors: Lyons John L. , Wickramaratne Darshana , Van de Walle Chris G.
Published: March 2021

Attaining control over the electrical conductivity of gallium nitride through impurity doping is one of the foremost achievements in semiconductor science. Yet, unwanted contaminants and point defects continue to limit device performance, and experimental techniques alone are insufficient for elucidating the behavior of these unintentionally incorporated species. Methodological advancements have made first-principles calculations more powerful than ever and capable of quantitative predictions, though care must still be taken in comparing results from theory and experiment. In this Tutorial, we explain the basic concepts that define the behavior of dopants, unintentional impurities, and point defects in GaN. We also describe how to interpret experimental results in the context of theoretical calculations and also discuss how the properties of defects and impurities vary in III-nitride alloys. Finally, we examine how the physics of defects and impurities in GaN is relevant for understanding other wide-bandgap semiconductor materials, such as the II–IV-nitrides, boron nitride, and the transition metal nitrides.
Re-evaluation of the electronic structure and thermoelectric properties of narrow-gap semiconducting α-SrSi2: A complementary experimental and first-principles hybrid-functional approach
Authors: Shiojiri Daishi , Iida Tsutomu , Kadono Tomoyuki , Yamaguchi Masato , Kodama Takuya , Yamaguchi Seiya , Takahashi Shinta , Kayama Yuki , Hiratsuka Kota , Imai Motoharu , Hirayama Naomi , Imai Yoji
Published: March 2021

Thermoelectric power generation in the low temperature region has attracted considerable attention as a means of the effective use of distributed energy and for sensor applications. However, it is difficult to theoretically predict the exact thermoelectric transport properties owing to the relatively narrow bandgap of low temperature thermoelectric materials. In this study, a high-purity α-SrSi2 crystal was synthesized by the vertical Bridgman (VB) method. The carrier density of the VB-grown α-SrSi2 was investigated, and, from the temperature dependence of the carrier density, it was estimated that the bandgap was 13.1 meV. First-principles calculations using the Heyd–Scuseria–Ernzerhof screened hybrid functional for α-SrSi2 predicted the bandgap to be very close to this value (13.27 meV) when assuming the mixing parameter of the Hartree–Fock contribution to the exact exchange is 18.7%. Using the calculated electronic structure and the measured carrier concentration, the predicted temperature dependence of the Seebeck coefficient was in good agreement with the experimental results.
Interaction of CO with Pt nanoclusters on a graphene-covered Ru(0001) surface
Authors: Esan Dominic A. , Trenary Michael
Published: March 2021

The adsorption of CO on Pt nanoclusters on a single layer of graphene epitaxially grown on the Ru(0001) surface [Gr/Ru(0001)] was studied with reflection absorption infrared spectroscopy (RAIRS) and temperature programmed desorption (TPD). The graphene layer was grown through exposure to ethylene using a method that has previously been shown to completely cover the surface. As CO adsorbs on Ru(0001) but not on graphene, the complete coverage of the Ru(0001) surface by graphene was verified with TPD as no CO adsorption was detectable. Previous work has demonstrated that Pt nanoclusters nucleate in the moiré unit cells of the Gr/Ru(0001) surface. Exposure of the Pt/Gr/Ru(0001) surface to CO gives rise to strong RAIRS peaks at 2065–2085 cm−1 assigned to CO at Pt atop sites and at 1848 cm−1 due to CO at Pt bridge sites. The CO TPD peak areas were used to quantify the CO coverage, which allowed for the determination of the RAIRS peak areas per CO molecule. It was found that the RAIRS intensity for CO on Pt/Gr/Ru(0001) is as much as nine times the intensity of CO on Ru(0001) on a per molecule basis. A more modest intensity enhancement was observed compared to CO on Pt islands on the Ru(0001) surface.
Effect of combined treatment of cesium fluoride as precursor and post-treatment on Cu(In,Ga)Se2 thin film solar cell
Authors: Khatri Ishwor , Sugiyama Mutsumi
Published: March 2021

In this study, we investigate the combined effect of cesium fluoride (CsF) as a precursor and post-treatment on a Cu(Inx,Ga1-x)Se2 (CIGS) thin film solar cell fabricated onto sodalime glass substrates. The combined treatment improves the open-circuit voltage, fill factor, and cell efficiency of the solar cell compared with its single counter treatment. Secondary ion mass spectroscopy measurements show a higher concentration of Cs diffusion in the surface regions in the combined treatment, which change the electronic properties of the buffer/CIGS interface by reducing interfacial recombination. Solar cells fabricated using CsF as a precursor indicate a deterioration in device performance owing to the formation of bulk defects, as confirmed from admittance spectroscopy. This study unveils device performance improvement by combining a heavy alkali metal as a precursor and post-treatment on CIGS thin film solar cells.
PASP: Property analysis and simulation package for materials
Authors: Lou Feng , Li X. Y. , Ji J. Y. , Yu H. Y. , Feng J. S. , Gong X. G. , Xiang H. J.
Published: March 2021

We have developed a software package, namely, PASP (Property Analysis and Simulation Package for materials), to analyze the structural, electronic, magnetic, and thermodynamic properties of complex condensed matter systems. Our package integrates several functionalities including symmetry analysis, global structure searching methods, effective Hamiltonian methods, and Monte Carlo simulation methods. In conjunction with first-principles calculations, PASP has been successfully applied to diverse physical systems. In this paper, we give a brief introduction to its main features and underlying theoretical formulism. Some typical applications are provided to demonstrate the usefulness, high efficiency, and reliability of PASP. We expect that further developments will make PASP a general-purpose tool for material simulation and property calculation of condensed matters.
Quantum–classical nonadiabatic dynamics of Floquet driven systems
Authors: Schirò Marco , Eich Florian G. , Agostini Federica
Published: March 2021

We develop a trajectory-based approach for excited-state molecular dynamics simulations of systems subject to an external periodic drive. We combine the exact-factorization formalism, allowing us to treat electron–nuclear systems in nonadiabatic regimes, with the Floquet formalism for time-periodic processes. The theory is developed starting with the molecular time-dependent Schrödinger equation with the inclusion of an external periodic drive that couples to the system dipole moment. With the support of the Floquet formalism, quantum dynamics is approximated by combining classical-like, trajectory-based, nuclear evolution with electronic dynamics represented in the Floquet basis. The resulting algorithm, which is an extension of the coupled-trajectory mixed quantum–classical scheme for periodically driven systems, is applied to a model study, exactly solvable, with different field intensities.
Localized potential well vs binding site: Mapping solute dynamics in a membrane channel onto one-dimensional description
Authors: Berezhkovskii Alexander M. , Bezrukov Sergey M. , Makarov Dmitrii E.
Published: March 2021

In the one-dimensional description, the interaction of a solute molecule with the channel wall is characterized by the potential of mean force U(x), where the x-coordinate is measured along the channel axis. When the molecule can reversibly bind to certain amino acid(s) of the protein forming the channel, this results in a localized well in the potential U(x). Alternatively, this binding can be modeled by introducing a discrete localized site, in addition to the continuum of states along x. Although both models may predict identical equilibrium distributions of the coordinate x, there is a fundamental difference between the two: in the first model, the molecule passing through the channel unavoidably visits the potential well, while in the latter, it may traverse the channel without being trapped at the discrete site. Here, we show that when the two models are parameterized to have the same thermodynamic properties, they automatically yield identical translocation probabilities and mean translocation times, yet they predict qualitatively different shapes of the translocation time distribution. Specifically, the potential well model yields a narrower distribution than the model with a discrete site, a difference that can be quantified by the distribution’s coefficient of variation. This coefficient turns out to be always smaller than unity in the potential well model, whereas it may exceed unity when a discrete trapping site is present. Analysis of the translocation time distribution beyond its mean thus offers a way to differentiate between distinct translocation mechanisms.
Magnetic modulation of mid and far-infrared plasmon resonances using the orientational magneto optical effect
Authors: Armelles Gaspar , Cebollada Alfonso
Published: March 2021

Arrays of in plane randomly placed aligned slits were engraved on an anisotropic magneto resistance Ni81Fe19 film, a material whose optical properties depend on the relative orientation of the light polarization and the magnetization direction (orientational magneto optical effect). In the 3–14 μm spectral range and for light polarized perpendicular to the slit axis, the reflectivity of the arrays presents a dip related to the excitation of the slit plasmon longitudinal resonance. We show that the intensity of this feature is different if the direction of the magnetization is parallel or perpendicular to the light polarization that excites this resonance. By varying the slit length, the spectral dependence of this magnetic modulation of the plasmon resonance has been analyzed. The results suggest that the orientational magneto optical effect could be used for magnetic modulation of plasmon resonances from the mid-infrared to the far-infrared spectral ranges.
Informing telehealth service delivery for cardiovascular disease management: exploring the perceptions of rural health professionals
Authors: Kocanda Lucy , Fisher Karin , Brown Leanne J. , May Jennifer , Rollo Megan E. , Collins Clare E. , Boyle Andrew , Schumacher Tracy L.
Published: March 2021

Objective To explore the perceptions of rural health professionals who use telehealth services for cardiovascular health care, including the potential role of telehealth in enhancing services for this patient group. Methods Semi-structured interviews were conducted with ten rural health professionals across a range of disciplines, including medicine, nursing and allied health. All study participants were based in the same rural region in New South Wales, Australia. Results Participant responses emphasised the importance of including rural communities in ongoing dialogue to enhance telehealth services for cardiovascular care. Divergent expectations about the purpose of telehealth and unresolved technology issues were identified as factors to be addressed. Rural health professionals highlighted the importance of all stakeholders coming together to overcome barriers and enhance telehealth services in a collaborative manner. Conclusion This study contributes to an evolving understanding of how health professionals based in regional Australia experience telehealth services. Future telehealth research should proceed in collaboration with rural communities, supported by policy that actively facilitates the meaningful inclusion of rural stakeholders in telehealth dialogue. What is known about the topic? Telehealth is frequently discussed as a potential solution to overcome aspects of rural health, such as poor outcomes and limited access to services compared with metropolitan areas. In the context of telehealth and cardiovascular disease (CVD), research that focuses on rural communities is limited, particularly regarding the experiences of these communities with telehealth. What does this paper add? This paper offers insight into how telehealth is experienced by rural health professionals. The paper highlights divergent expectations of telehealth’s purpose and unresolved technological issues as barriers to telehealth service delivery. It suggests telehealth services may be enhanced by collaborative approaches that engage multiple stakeholder groups. What are the implications for practitioners? The use and development of telehealth in rural communities requires a collaborative approach that considers the views of rural stakeholders in their specific contexts. To improve telehealth services for people living with CVD in rural communities, it is important that rural stakeholders have opportunities to engage with non-rural clinicians, telehealth developers and policy makers.
First record of a pygmy sperm whale (
Authors: Dehm Jasha , Varea Rufino , Hewavitharane Chinthaka Anushka , Stockwell Brian , Brown Kelly Thomas
Published: March 2021

On 18 July 2020, a small whale was found stranded along the eastern shoreline of Viti Levu, Fiji. The whale died two days later despite efforts to refloat and guide it out to sea. Morphometric measurements and photo identification confirm it to be an adult male pygmy sperm whale, Kogia breviceps (Blanville, 1838). This specimen acts as the first confirmed record of the species in Fiji.
Sexual development and maturity of the male brown banded bamboo shark,
Authors: Sephid Hesam , Salamat Negin , Salari Mohammad Ali
Published: March 2021

The present study aimed to assess the reproductive biology of male brown banded bamboo shark (Chiloscyllium punctatum). Morphological and histological changes in the reproductive tract and changes in gonad steroid testosterone were assessed in 110 male C. punctatum collected from Bahrakan Creek between January 2018 and March 2019. The reproductive tract in male C. punctatum consisted of a pair of testes, efferent ducts, epididymidis, ductus deferens, seminal vesicles, Leydig gland and claspers. Four sexual development stages were determined: (1) immature, no calcified claspers (2) maturing, partially calcified claspers; (3) active and resting adults. Both adult resting and active stages had calcified claspers. In this study, immature male C. punctatum without calcified claspers were found from August to October, maturing C. punctatum with partially calcified claspers were found from November to January and adult C. punctatum caught from February to April were active with calcified claspers, whereas adult fish collected from May to July and during the rest of the year (until mid-January in the following year) were in the resting stage with inactive testes. The testis had a lobular structure and the spermatocysts were arranged diametrically (i.e. along the cross-sectional width of the testis) in each lobule. Plasma testosterone concentrations were associated with histomorphological changes in the reproductive tract. Testosterone concentrations peaked in March in active males and then decreased significantly in resting males. Overall, the variations in the reproductive organs during different sexual maturity stages were consistent with their roles in the production, movement and release of spermatozoa.
Immunoediting role for major vault protein in apoptotic signaling induced by bacterial
N
-acyl homoserine lactones
Authors: Rayo Josep , Gregor Rachel , Jacob Nicholas T. , Dandela Rambabu , Dubinsky Luba , Yashkin Alex , Aranovich Alexander , Thangaraj Manikandan , Ernst Orna , Barash Eran , Malitsky Sergey , Florea Bogdan I. , Krom Bastiaan P. , Wiemer Erik A. C. , Kickhoefer Valerie A. , Rome Leonard H. , Mathison John C. , Kaufmann Gunnar F. , Overkleeft Herman S. , Cravatt Benjamin F. , Zor Tsaffrir , Janda Kim D. , Ulevitch Richard J. , Kravchenko Vladimir V. , Meijler Michael M.
Published: March 2021

Significance

It has become clear that our immune system can significantly inhibit the growth of cancer cells, in a process that has been coined “cancer immunoediting.” Based on this model, if the programmed cell death (apoptosis) mediated through immunosurveillance processes is not successful, the tumor cells may enter an equilibrium phase where they are either maintained or “edited” immunologically, leading to populations of tumor variants in the escape phase. Microbial factors have been found to affect cancer immunoediting. In this study we have identified a central player in these processes, called the major vault protein (MVP). Binding of certain bacterial signaling molecules to MVP strongly modulates apoptotic signaling, provoking new ideas and avenues to understand human-bacterial relationships and fight cancer.
A conformational switch driven by phosphorylation regulates the activity of the evolutionarily conserved SNARE Ykt6
Authors: McGrath Kaitlyn , Agarwal Shivani , Tonelli Marco , Dergai Mykola , Gaeta Anthony L. , Shum Andrew K. , Lacoste Jessica , Zhang Yongbo , Wen Wenyu , Chung Daayun , Wiersum Grant , Shevade Aishwarya , Zaichick Sofia , van Rossum Damian B. , Shuvalova Ludmilla , Savas Jeffrey N. , Kuchin Sergei , Taipale Mikko , Caldwell Kim A. , Caldwell Guy A. , Fasshauer Dirk , Caraveo Gabriela
Published: March 2021

Significance

Ykt6 is a conserved SNARE that plays critical roles along multiple vesicular pathways. To achieve its function, Ykt6 cycles between the cytosol and membrane-bound compartments through reversible lipidation. The mechanism that regulates these transitions is unknown. Ykt6 function is disrupted by α-synuclein, a protein critically implicated in synucleinopathies such as Parkinson’s Disease. Through a multidisciplinary approach, we report that phosphorylation regulated by Ca2+signaling drives a conformational change that allows Ykt6 to switch from a closed cytosolic to an open membrane-bound form. Phosphorylation is also a critical determinant for Ykt6 protein interactions with functional consequences in the secretory and autophagy pathways under normal and α-synuclein conditions. This work provides a mechanistic insight into Ykt6 regulation with therapeutic implications for synucleinopathies.
Estimating maximal microbial growth rates from cultures, metagenomes, and single cells via codon usage patterns
Authors: Weissman J. L. , Hou Shengwei , Fuhrman Jed A.
Published: March 2021

Maximal growth rate is a basic parameter of microbial lifestyle that varies over several orders of magnitude, with doubling times ranging from a matter of minutes to multiple days. Growth rates are typically measured using laboratory culture experiments. Yet, we lack sufficient understanding of the physiology of most microbes to design appropriate culture conditions for them, severely limiting our ability to assess the global diversity of microbial growth rates. Genomic estimators of maximal growth rate provide a practical solution to survey the distribution of microbial growth potential, regardless of cultivation status. We developed an improved maximal growth rate estimator and predicted maximal growth rates from over 200,000 genomes, metagenome-assembled genomes, and single-cell amplified genomes to survey growth potential across the range of prokaryotic diversity; extensions allow estimates from 16S rRNA sequences alone as well as weighted community estimates from metagenomes. We compared the growth rates of cultivated and uncultivated organisms to illustrate how culture collections are strongly biased toward organisms capable of rapid growth. Finally, we found that organisms naturally group into two growth classes and observed a bias in growth predictions for extremely slow-growing organisms. These observations ultimately led us to suggest evolutionary definitions of oligotrophy and copiotrophy based on the selective regime an organism occupies. We found that these growth classes are associated with distinct selective regimes and genomic functional potentials.
Ancient plant DNA reveals High Arctic greening during the Last Interglacial
Authors: Crump Sarah E. , Fréchette Bianca , Power Matthew , Cutler Sam , de Wet Gregory , Raynolds Martha K. , Raberg Jonathan H. , Briner Jason P. , Thomas Elizabeth K. , Sepúlveda Julio , Shapiro Beth , Bunce Michael , Miller Gifford H.
Published: March 2021

Significance

The Arctic is warming exceptionally rapidly, promoting an expansion of shrubs across the Arctic with global-scale climate implications. The Last Interglacial (∼125,000 y ago) was the most recent time the Arctic was warmer than present and thus serves as an analogue for Arctic greening in the near future. Ancient plant DNA in lake sediment from this time reveals major ecosystem changes in response to warmth, including an ∼400 km northward shift of dwarf birch relative to today. Enhanced shrub cover, corroborated by molecular and microfossil analyses, amplified warming during the Last Interglacial and will likely play a similar role in the future. This record constitutes the oldest authenticated plant DNA from lake sediment yet reported, increasing the technique’s temporal potential.