bluuebunny/crossref_metadata_2025 huggingface dataset:
Target-mediated base-mismatch initiation of a non-enzymatic signal amplification network for highly sensitive sensing of Hg2+
Authors: Li Daxiu , Yang Fang , Li Xin , Yuan Ruo , Xiang Yun
Published: October 2019

Target-triggered initiation of a non-enzymatic signal amplification network leads to highly sensitive fluorescence detection of Hg2+.
Possible magnetic correlation above the ferromagnetic phase transition temperature in Cr2Ge2Te6
Authors: Sun Y. , Tong W. , Luo X.
Published: October 2019

The magnetic correlation above the ferromagnetic phase transition temperature plays an important role in the ferromagnetism in Cr2Ge2Te6.
Coenzyme Q10 attenuates platelet integrin αIIbβ3 signaling and platelet hyper-reactivity in ApoE-deficient mice
Authors: Ya Fuli , Xu Xiaohong Ruby , Tian Zezhong , Gallant Reid C. , Song Fenglin , Shi Yilin , Wu Yinfan , Wan Jianbo , Zhao Yimin , Adili Reheman , Ling Wenhua , Ni Heyu , Yang Yan
Published: October 2019

CoQ10 supplementation in ApoE−/− mice attenuates high-fat diet-induced platelet hyper-reactivity via down-regulating platelet αIIbβ3 signaling, and thus protecting against atherothrombosis.
Correction: Surface hardness and flammability of Na2SiO3 and nano-TiO2 reinforced wood composites
Authors: Garskaite Edita , Karlsson Olov , Stankeviciute Zivile , Kareiva Aivaras , Jones Dennis , Sandberg Dick
Published: October 2019

Correction for ‘Surface hardness and flammability of Na2SiO3 and nano-TiO2 reinforced wood composites’ by Edita Garskaite et al., RSC Adv., 2019, 9, 27973–27986.
Correction: The selective hydrosilylation of norbornadiene-2,5 by monohydrosiloxanes
Authors: Guseva Marina A. , Alentiev Dmitry A. , Bermesheva Evgeniya V. , Zamilatskov Ilya A. , Bermeshev Maxim V.
Published: October 2019

Correction for ‘The selective hydrosilylation of norbornadiene-2,5 by monohydrosiloxanes’ by Marina A. Guseva et al., RSC Adv., 2019, 9, 33029–33037.
Oligo(ethylene glycol) side chain effect on the physical properties and molecular arrangement of oligothiophene–isoindigo based conjugated polymers
Authors: Chen Chien-An , Wang Shih-Chieh , Tung Shih-Huang , Su Wei-Fang
Published: October 2019

Incorporation of an oligo(ethylene glycol) side chain into an oligothiophene–isoindigo based conjugated polymer can tune the polymer packing orientation.
Hybrid precoding design for millimetre wave systems with the partially‐connected structure
Authors: Wang Ye , Zou Weixia
Published: October 2019

Millimetre wave (mmWave) communication is a promising technique for fifth generation networks. Hybrid precoding is introduced to mmWave communication systems to provide a reasonable trade‐off strategy between system performance and energy cost. The hybrid precoder with the partially‐connected structure has relatively low hardware complexity and less energy consumption. In this study, the authors decompose the optimisation problem of analogue precoder into several subproblems, and introduce a heuristic method to find the solution. Then, they obtain the digital precoder according to the product of the channel matrix and analogue precoding matrix. Numerical simulations show that the proposed algorithm performs well in most cases. Considering the error of channel estimation or the finite resolution of phase shifters, the proposed algorithm is able to provide acceptable spectral efficiency as well.
Two constructions of zero correlation zone aperiodic complementary sequence sets
Authors: Chen Xiaoyu , Li Guanmin , Li Huanchang
Published: October 2019

Two constructions of zero correlation zone (ZCZ) aperiodic complementary sequence (ZACS) sets are presented. Based on aperiodic complementary sequence (ACS) sets and orthogonal matrices, construction 1 proposed ZACS sets by utilising cascade operation. Also, the parameters of the resulting sets are optimal if the original ACS sets can achieve the theoretical bound. In construction 2, according to different setting methods of , two classes of ZACS sets are presented based on two orthogonal matrices, and the length of ZCZ can be chosen flexibly. Furthermore, compared with the existing references, the order of the two orthogonal matrices can be different. The ZACS sets presented in this study are of practical interest in multi‐carriers code division multiple access systems.
Optimal Strategy of Active Distribution Network Considering Source–Network–Load
Authors: Kong Xiangyu , Yong Chengsi , Wang Chengshan , Chen Ying , Yu Li
Published: October 2019

With the access of renewable distributed generations and the uncertainty of demand‐side response, the operation states of the active distribution network (ADN) are uncertain. This study proposes a novel optimal strategy taking active management costs of the source–network–load as the goal and considering the site selection and the incentive price for the responsive load to optimise the ADN. To deal with uncertainties, a chance‐constrained optimisation model is established and the Monte Carlo sampling method is used. Then, the uncertain model is settled by the improved backtracking search algorithm, which uses an adaptive mutation scale factor. Finally, the practicability of the proposed strategy and the performance of the algorithm are verified by the modified IEEE 33‐bus distribution system and an actual distribution system in China.
Comprehensive approach for distribution system planning with uncertainties
Authors: Seta Felipe da Silva , de Oliveira Leonardo W. , de Oliveira Edimar J.
Published: October 2019

This study presents a comprehensive approach for the distribution system expansion planning (DSEP) that considers investment, operation, carbon dioxide emission and reliability costs, as well as uncertainties over load demand and wind‐based distributed generation. A restoration strategy is taken into account for obtaining the energy not supplied under the ‘N − 1’ criterion and the corresponding reliability cost over a planning horizon. The problem is modelled as mixed‐integer non‐linear programming by using the artificial immune system algorithm. Also, two methods to represent uncertainties are applied and compared: an interval technique through an interval power flow and a scenario‐based approach. Network constraints are considered, as the limits of current, voltage and power from substations, as well as the obtaining of radial and connected topology. The novelty of the proposed interval DSEP consists of handling the uncertainties over operation in an efficient manner through a single step, instead of the several deterministic evaluations of the scenario‐based approach. Numerical results are presented for well known test systems, which show the potentials of the proposed approach.
Novel coated differentially fed dual‐band fractal antenna for implantable medical devices
Authors: Fan Yi , Liu Hui , Liu XiongYing , Cao Yan , Li ZhongXin , Tentzeris Manos M.
Published: October 2019

A novel differentially fed fractal antenna coated with a layer of a dielectric film and operating at two bands of Medical Implant Communication Services 402–405 MHz and Industrial, Scientific, and Medical 2.4–2.48 GHz, is investigated to enable sufficient data transmission rates, while featuring a ‘mode‐control’ signal to prolong the battery life. The symmetrical fractal technology of Hilbert curve is employed to miniaturise the dimension. To facilitate interfacing with peripheral integrated circuits, differentially feeding is adopted. To demonstrate how common‐mode noises are suppressed, for the first time, a detailed analysis about the noise suppression of the differential configuration with two feedings is presented. A layer of thin film is coated around the proposed antenna to isolate the effect of human tissues and alleviate the electromagnetic coupling with human body. Moreover, to draw a design methodological guideline, the key geometrical parameters are analysed numerically and theoretically. Health safety considerations, radiation performance, and link budgets are also discussed to validate the proposed antenna's applicability in biomedical telemetry.
Research on low input current ripple two‐stage converter for low frequency pulsed‐power applications
Authors: Gu Yu , Zhang Donglai , Fang Mingzhu , Zhang Xiaofeng , Qi Pengyu
Published: October 2019

In this study, a two‐stage cascaded pulsed power converter based on the proposed optimised control scheme has been presented. In order to eliminate the low‐frequency input current ripple, the front‐stage converter only needs to provide average power and the second‐stage converter provides pulsed power. Meanwhile, the isolation of energy transfer mode combines with the proposed optimised control method based on the input current AC signal feedback control guarantee smooth input power with low repeat frequency pulsed load. To demonstrated the effectiveness of the proposed low‐frequency input current ripple cancellation technique, a 1 kW peak pulsed power prototype is built and tested. The experimental results verify the validity and reliability of the two‐stage isolated pulsed power converter with proposed optimised control method, and the proposed methods and concepts in this study can also be applied to all kinds of pulsed power applications.
Design of a sprayer for complex treatment of tilled crops
Authors: Belousova Anna I. , Moiseev Arkadiy V. , Fillipov Dmitry A.
Published: October 2019

The article is devoted to the complex processing of tilled crops by the proposed sprayer. The article has a research character which is expressed in the fact that there was shown the analysis of methods and means of chemical protection of plants as well as the analysis of the leading scientists on the subject, promising designs that provide optimal chemical treatment of tilled crops, their shortcomings and solutions to these problems were cited. There was defined the main tendency of development of machines for chemical protection of plants, improvement of their design according to modern requirements of agricultural development. Also, there was justified the design of the sprayer, namely, the results of scientific researches, there were shown the causal relationship of the number of spraying tips from the width and the grip of working area. There was described the principle and operation process of the developed sprayer. As a result of the work there was obtained the design for the complex processing of tilled crops. The conclusions present the main results achieved so far.
Analytical substantiation of constructive parameters of rotating field board of plow’s body
Authors: Konovalov Vladimir , Konovalov Sergey , Igumnova Victoria
Published: October 2019

The article shows importance of use of dump plowing for formation and maintenance of soil structure and pest control and diseases of cultivated plants. A significant drawback of plowing process is indicated, which is its high energy intensity. To reduce energy consumption, it is proposed to use rotating field boards, which allow replacing sliding friction forces with rolling friction forces. The article presents a description of design of plow’s body with rotating field board and notes that without a preliminary analytical study and justification of initial parameters, their use may not be effective. Analytical relations connecting value of radius of rotating field of board, rate of collapse of soil, allowable value of indentation of field board into soil and specific force of cutting resistance of soil that ability to use it for baseline technical parameters. To analyze obtained dependence, the article presents its graphical solution. The authors obtained an expression for determining the value of arm’s force of reference reaction from soil to balance a plow’s body, in addition, this indicator can be used to adjust a body when working on soils with different physical and mechanical parameters and at different depths.
Justification of the choice of the type of forage harvester for farms
Authors: Golovkov Aleksandr , Boiko Andrey , Chaava Mikhail
Published: October 2019

The results of tests of feed-harvesting combines of domestic and foreign manufacturers for the last ten years are presented. Recommendations on the choice of the studied equipment are given.
Numerical modeling of space umbrella-type mesh reflector
Authors: Belov Sergey , Belkov Aleksey , Zhukov Andrey , Pavlov Mikhail , Kuznetsov Stanislav , Ponomarev Sergey
Published: October 2019

This paper describes numerical modeling of space umbrella-type mesh reflector. The modeling includes two stages. The first stage embraces the calculation of the shape of cable elements for reflector frontal (rear) nets by the nonlinear force density method. The second stage involves the design of the reflector finite-element model based on the calculated nets. After this, the node displacement and prestress boundary conditions are imposed to determine a node displacement field.
Different stages of the evolution of cerebral aneurysms: joint analysis of mechanical test data and histological analysis of aneurysm tissue
Authors: Parshin Daniil , Lipovka Anna , Dubovoy Andrey , Vasilyeva Mariya , Kuznetsova Elena , Sergeevichev David
Published: October 2019

In practical neurosurgery, an important issue is determining the status of the aneurysm and predicting its further growth, rupture or stabilization. The main approaches for the study of risk analysis asessment are computational hydrodynamics and analysis of the mechanics of the wall of cerebral aneurysm. In this paper, an analysis of various sections of the wall of cerebral aneurysm is given, combining mechanical test data and histological examination data. It was shown that, along with significant diﬀerences in mechanics, a diﬀerent degree of calcification is observed in the tissue, which indicates a diﬀerent level of impaired transport of substances inside the tissue.
Numerical approximations for fractional elliptic equationsviathe method of semigroups
Authors: Cusimano Nicole , del Teso Félix , Gerardo-Giorda Luca
Published: October 2019

We provide a novel approach to the numerical solution of the family of nonlocal elliptic equations (−Δ)su=fin Ω, subject to some homogeneous boundary conditionsBon ∂Ω, wheres∈ (0,1), Ω ⊂ ℝnis a bounded domain, and (-Δ)sis the spectral fractional Laplacian associated toBon ∂Ω. We use the solution representation (−Δ)−sftogether with its singular integral expression given by the method of semigroups. By combining finite element discretizations for the heat semigroup with monotone quadratures for the singular integral we obtain accurate numerical solutions. Roughly speaking, given a datumfin a suitable fractional Sobolev space of orderr≥ 0 and the discretization parameterh> 0, our numerical scheme converges asO(hr+2s), providing super quadratic convergence rates up toO(h4) for sufficiently regular data, or simplyO(h2s) for merelyf∈L2(Ω). We also extend the proposed framework to the case of nonhomogeneous boundary conditions and support our results with some illustrative numerical tests.
Comparison of Clinical Symptoms of Assumed vs. Actual Uterine Fibroids – Symptoms Described by Patients and Ultrasound Findings
Authors: Knudsen Nina Isabelle , Wernecke Klaus-D. , Kentenich Heribert , David Matthias
Published: October 2019

Purpose How many women assume that they have fibroids but are found not to have fibroids on ultrasound examination? How severe are the physical symptoms reported by these women compared to the symptoms reported by women with actual uterine fibroids? Are the symptoms more severe if the patient believes that she has at least one relatively large (dominant) fibroid or more than 3 fibroids?

Material and Methods A total of 1548 patients completed an anonymous questionnaire in which they were asked about the number of their fibroids, dysmenorrhea and premenstrual symptoms, dyspareunia and bleeding disorders (using a numerical analog scale between 0 – 10). The questionnaire was administered in a hospital-based fibroid clinic. The information provided by the patients was then compared with transvaginal or abdominal ultrasound findings. The symptoms reported by women with and without fibroid(s) were compared.

Results 1045 out of 1548 patients fulfilled the studyʼs inclusion criteria. Contrary to the information they provided, no fibroid(s) were detected in 6% (62 of 1045 patients) of patients on ultrasound examination. Of these women, 87% had dysmenorrhea, 79% had premenstrual pain and 57% reported dyspareunia. The severity of the symptoms was found not to be associated with the assumed size or number of fibroid(s). There was no significant difference in the pain reported by women without and by women with fibroids. Reporting a feeling of strong pressure on the bladder (OR: 1.18) or abdomen (OR: 1.12) or constipation (OR: 1.16) increased the likelihood of detecting a fibroid on ultrasound investigation.

Conclusions The presence of manifest symptoms (dysmenorrhea, dyspareunia, premenstrual pain, bleeding disorders) does not allow conclusions to be made about the number or size of fibroids or about which therapy is indicated. Even an erroneous assumption about the presence of fibroids may result in patients experiencing symptoms.
Nasennebenhöhlenchirurgie an deutschen HNO-Kliniken – eine Bestandsaufnahme
Authors: Hildenbrand Tanja , Knopf Andreas , Ketterer Manuel Christoph
Published: October 2019

Hintergrund Die Nasennebenhöhlenchirurgie hat sich in den letzten Jahrzehnten wesentlich weiterentwickelt, hin zur endonasalen endoskopischen Chirurgie zur Therapie von benignen und malignen Erkrankungen der Nasennebenhöhlen. Das Ziel der vorliegenden Untersuchung war die Erfassung des aktuellen Standes der Nasennebenhöhlenchirurgie in HNO-Kliniken in Deutschland.

Material und Methode Ein Fragebogen mit Fragen zu OP-Zahlen, OP-Technik, technischer Ausstattung, interdisziplinärer Zusammenarbeit, Nachsorge, Nutzung von CT-Checklisten, Ausbildung und Bewertung der Lebensqualität wurde an alle Ordinarien und Chefärzte von HNO-Kliniken in Deutschland versandt.

Ergebnisse Die Rücklaufquote betrug 79,5 %. 89,1 % der Kliniken geben an, 200–400 oder mehr als 400 Eingriffe bei benignen Erkrankungen der Nasennebenhöhlen durchzuführen. Die Zahl der durchgeführten Eingriffe bei malignen Erkrankungen ist deutlich geringer. Nur ein Teil der Kliniken, die Patienten in einem interdisziplinären Tumorboard vorstellen, führen auch interdisziplinäre Tumoroperationen durch. Die meisten Kliniken geben an, sowohl ein Endoskopie- als auch ein Navigationssystem für die Nasennebenhöhlenchirurgie zu besitzen. Die Ausbildung von Assistenzärzten in der Nasennebenhöhlenchirurgie beginnt meist zwischen dem 2. und 4. Jahr und in fast allen Kliniken werden Dissektionskurse während der Ausbildung besucht. Mehr als die Hälfte der Kliniken nutzt eine CT-Checkliste zur präoperativen Analyse von CT-Bildern. Die Lebensqualität vor und nach Operationen an den Nasennebenhöhlen wird nur in wenigen Kliniken bestimmt.

Schlussfolgerung Unsere Untersuchung zeigt ein repräsentatives Bild des aktuellen Standes der Nasennebenhöhlenchirurgie in der stationären Versorgung in Deutschland.
The Impact of Hepatitis C Virus Infection on Buprenorphine Dose in Pregnancy
Authors: McDowell Misty L. , Tonismae Tiffany R. , Slaven James E. , Abernathy Mary P. , Shanks Anthony L. , Benjamin Tara D. , Quinney Sara K.
Published: October 2019

Objective Buprenorphine (BUP) is commonly used for opioid maintenance therapy in pregnancy. Our goal was to determine whether liver dysfunction related to hepatitis C virus (HCV) infection impacts BUP dosing requirements in pregnancy.

Study Design This was a retrospective cohort study of pregnant women with antenatal exposure to BUP to compare dosing between individuals positive versus negative for HCV infection. Spearman correlation tests were used to assess the relationship between BUP dose and HCV status.

Results HCV infection was present in 103 (39%) of the patients. Patients with HCV infection required lower dose increases of BUP throughout pregnancy (p = 0.02). HCV viral load was positively correlated with the liver enzymes aspartate transaminase (r = 0.30, p = 0.003) and alanine transaminase (r = 0.25, p = 0.01). There was a negative correlation between HCV viral load and BUP dose during the second trimester (r = −0.27, p = 0.01) and third trimester (r = −0.20, p = 0.04).

Conclusion Women with HCV infection required less of an increase in BUP dose throughout pregnancy compared with women without HCV infection. Severity of HCV infection, as measured by viral load and liver enzymes, was also associated with BUP dosing.
Three-phase metal-insulator transition and structural alternative for a VO2 film epitaxially grown on Al2O3(0001)
Authors: Bailly A. , Grenier S. , Villamayor M. M. , Gaudin M. , Ramos A. Y. , Bouvier P. , Bouchard C. , Magaud L. , Laversenne L. , Mongellaz B. , Bellet-Amalric E. , Lacoste A. , Bès A.
Published: October 2019

We report on the crystallographic phases and their epitaxial relationships observed during the metal-insulator transition (MIT) of a VO2 film deposited on Al2O3(0001). A key feature of this work is to establish two possible in-plane epitaxial relationships for the VO2 film, introducing an “on-axis” and a “diagonal” model. These models have distinctive signatures in reciprocal spaces in the form of multiplet reflections and can, therefore, be easily differentiated by diffraction. They serve as a basis for interpreting the results gained by high-resolution X-ray diffraction, and complemented by Raman spectroscopy, on a 420-nm-thick VO2 film grown by microwave plasma-assisted reactive sputtering on Al2O3(0001). We address its orientation and follow its structure through the MIT. The film is oriented according to the diagonal model and exhibits a MIT involving three phases with different temperature domains of (co)existence. The room- and high-temperature phases are, respectively, identified as the monoclinic M1 and rutile R polymorphs of VO2. Additionally, we observe that when the sample resistivity starts to decrease, the insulating M1 phase turns into an intermediary phase, which then partially transforms into the metallic R phase when the MIT is complete. The intermediary phase is similar to the M2 polymorph of VO2, according to its lattice parameters, Raman signature, and its known proximity with the M1 and R phases in tensile conditions. The mixing of the M2 and R phases is still detected at 110°C, i.e., far above the MIT; the M2 polymorph is being probably stabilized at the interface between the film and the substrate, where the interfacial strain is higher.
Absorption-emission symmetry breaking and the different origins of vibrational structures of the 1Qy and 1Qx electronic transitions of pheophytin a
Authors: Rätsep Margus , Linnanto Juha Matti , Muru Renata , Biczysko Malgorzata , Reimers Jeffrey R. , Freiberg Arvi
Published: October 2019

The vibrational structure of the optical absorption and fluorescence spectra of the two lowest-energy singlet electronic states (Qy and Qx) of pheophytin a were carefully studied by combining low-resolution and high-resolution spectroscopy with quantum chemical analysis and spectral modeling. Large asymmetry was revealed between the vibrational structures of the Qy absorption and fluorescence spectra, integrally characterized by the total Huang-Rhys factor and reorganization energy in absorption of SvibA = 0.43 ± 0.06, λA = 395 cm−1 and in emission of SvibE = 0.35 ± 0.06, λE = 317 cm−1. Time-dependent density-functional theory using the CAM-B3LYP, ωB97XD, and MN15 functionals could predict and interpret this asymmetry, with the exception of one vibrational mode per model, which was badly misrepresented in predicted absorption spectra; for CAM-B3LYP and ωB97XD, this mode was a Kekulé-type mode depicting aromaticity. Other computational methods were also considered but performed very poorly. The Qx absorption spectrum is broad and could not be interpreted in terms of a single set of Huang-Rhys factors depicting Franck-Condon allowed absorption, with Herzberg-Teller contributions to the intensity being critical. For it, CAM-B3LYP calculations predict that SvibA (for modes >100 cm−1) = 0.87 and λA = 780 cm−1, with effective x and y polarized Herzberg-Teller reorganization energies of 460 cm−1 and 210 cm−1, respectively, delivering 15% y-polarized intensity. However, no method was found to quantitatively determine the observed y-polarized contribution, with contributions of up to 50% being feasible.
Passivating and low-resistive poly-Si tunneling junction enabling high-efficiency monolithic perovskite/silicon tandem solar cells
Authors: Luderer C. , Reichel C. , Feldmann F. , Bivour M. , Hermle M.
Published: October 2019

We present a p+/n+ poly-Si tunneling junction (TJ) based on a tunnel oxide passivated contact (TOPCon) that enables both low contact resistivity ρc and high implied open-circuit voltages iVoc. It will be shown that the charge carrier profile of the TJ and the junction resistance are strongly affected by the applied thermal budget, consisting of a furnace anneal and/or a rapid thermal processing treatment, and the deposition parameters of the a-Si layers. A minimum combined junction resistance of the p+/n+ poly-Si/SiOx stack of less than 10 mΩ cm2 and iVoc of up to 726 mV at 1 sun illumination is reported. This work aims for incorporation of our p+/n+ poly-Si TJ into an industrially feasible tandem solar cell featuring a Si bottom cell with a TOPCon front emitter and the industrial standard technology of a passivated emitter and rear cell rear structure.
Asymmetric and long range interactions in shaken granular media
Authors: Codina Joan , Pagonabarraga Ignacio
Published: October 2019

We use a computational model to investigate the emergence of interaction forces between pairs of intruders in a horizontally vibrated granular fluid. The time evolution of a pair of particles shows a maximum of the likelihood to find the pair at contact in the direction of shaking. This relative interaction is further studied by fixing the intruders in the simulation box where we identify effective mechanical forces and torques between particles and quantify an emergent long range attractive force as a function of the shaking relative angle, the amplitude, and the packing density of grains. We determine the local density and kinetic energy profiles of granular particles along the axis of the dimer to find no gradients in the density fields and additive gradients in the kinetic energies.
A chemical potential equalization approach to constant potential polarizable electrodes for electrochemical-cell simulations
Authors: Nakano Hiroshi , Sato Hirofumi
Published: October 2019

Atomistic modeling of electrochemical systems is one of the most challenging topics in the field of molecular simulations. We derive the equations for modeling constant potential polarizable electrodes in electrochemical-cell simulations based on the chemical potential equalization principle. They reduce to those derived by Siepmann and Sprik [J. Chem. Phys. 102, 511 (1995)], later arranged by Reed, Lanning, and Madden [J. Chem. Phys. 126, 084704 (2007)] under some assumptions. The present approach clarifies the physical meaning of the total energy of a system that includes classical polarizable electrodes, which is important in order to analyze the energetics of chemical phenomena at electrode-electrolyte interfaces. The effects of the Hubbard U parameter of an electrode atom are discussed in connection with the perfect conductor limit for a metal electrode.
On the calculation of the bandgap of periodic solids with MGGA functionals using the total energy
Authors: Tran Fabien , Doumont Jan , Blaha Peter , Marques Miguel A. L. , Botti Silvana , Bartók Albert P.
Published: October 2019

During the last few years, it has become more and more clear that functionals of the meta generalized gradient approximation (MGGA) are more accurate than GGA functionals for the geometry and energetics of electronic systems. However, MGGA functionals are also potentially more interesting for the electronic structure, in particular, when the potential is nonmultiplicative (i.e., when MGGAs are implemented in the generalized Kohn-Sham framework), which may help to get more accurate bandgaps. Here, we show that the calculation of bandgap of solids with MGGA functionals can also be done very accurately in a non-self-consistent manner. This scheme uses only the total energy and can, therefore, be very useful when the self-consistent implementation of a particular MGGA functional is not available. Since self-consistent MGGA calculations may be difficult to converge, the non-self-consistent scheme may also help to speed up the calculations. Furthermore, it can be applied to any other types of functionals, for which the implementation of the corresponding potential is not trivial.
Towards efficient density functional theory calculations without self-interaction: The Fermi-Löwdin orbital self-interaction correction
Authors: Jackson K. A. , Peralta J. E. , Joshi R. P. , Withanage K. P. , Trepte K. , Sharkas K. , Johnson A. I.
Published: October 2019

The Fermi-Löwdin orbital (FLO) approach to the Perdew-Zunger self-interaction correction (PZ-SIC) to density functional theory (DFT) is described and an improved approach to the problem of optimizing the Fermi-orbitals in order to minimize the DFT-SIC total energy is introduced. To illustrate the use of the FLO-SIC method, results are given for several applications involving problems where self-interaction errors are pronounced.
Near-term Quantum Algorithms for Quantum Many-body Systems
Authors: Ritter Mark B.
Published: October 2019

There has been a good deal of work on algorithms to simulate quantum many-body systems with fault-tolerant quantum computers- those with full error correction. Fault-tolerant quantum computers of scale requisite to achieve computational advantage for these problems are likely over a decade away. Moreover, devices that we can build in the near term, called Noisy Intermediate Scale Quantum computers (NISQ), have too much noise to implement the long circuits required by these algorithms. We review heuristic, short-depth quantum algorithms more suited to NISQ computers; specifically, their scaling properties when applied to electronic and nuclear structure calculations, including Hamiltonian complexity with particle number, ansatz state preparation, convergence, and noise. We will present examples of actual quantum structure calculations with NISQ computers, as well as a newly-developed error mitigation technique that significantly improves accuracy. We end with an outlook for “advantage” – when NISQ systems might excel conventional HPC approaches for comparable problems.
Ground state phase diagram of the one-dimensional Bose-Hubbard model from restricted Boltzmann machines
Authors: McBrian Kristopher , Carleo Giuseppe , Khatami Ehsan
Published: October 2019

Motivated by recent advances in the representation of ground state wavefunctions of quantum many-body systems using restricted Boltzmann machines as variational ansatz, we utilize an open-source platform for constructing such ansatz called NetKet to explore the extent of applicability of restricted Boltzmann machines to bosonic lattice models. Within NetKet, we design and train these machines for the one-dimensional Bose-Hubbard model through a Monte Carlo sampling of the Fock space. We vary parameters such as the strength of the onsite repulsion, the chemical potential, the system size and the maximum site occupancy and use converged equations of state to identify phase boundaries between the Mott insulating and superfluid phases. We compare the average density and the energy to results from exact diagonalization and map out the ground state phase diagram, which agrees qualitatively with previous finding obtained through conventional means.
A First Look at Lattice Effects in Coarse-Grained Protein Models via Wang-Landau Simulations
Authors: Farris Alfred C.K. , Seaton Daniel T. , Landau David P.
Published: October 2019

In order to study the effects of lattice constraints on coarse-grained protein models, we apply Wang-Landau sampling to the continuum analogue of the hydrophobic-polar (HP) lattice protein model. The continuum version is inspired by the AB polymer model but incorporates potentials chosen specifically to mimic those of the lattice case. Because of their relative simplicity, both the lattice and continuum models offer significant computational advantage over all-atom simulations, but the impact of the additional lattice constraint on generic folding behavior is unknown. In this preliminary study, we compare and contrast thermodynamics during the folding process of the continuum model to the original HP lattice protein model for sequences mapped from Crambin, a 46 amino acid plant protein. We find that the folding process for both of these coarse-grained models is quite similar, with major structural transitions occurring at almost exactly the same temperatures.
Propagation of dust ion acoustic solitary waves in dusty plasma with Boltzmann electrons
Authors: Das S.
Published: October 2019

In this multispecies plasma model, consisting of negative mobile dusts, non-thermal ions and Boltzmann electrons, dust-ion acoustic solitary waves are studied through reductive perturbative technique by deriving corresponding Korteweg-de Vries (KdV) equation. The number of dust charge contained in a dust particle (Zd) and the streaming speeds of mobile dusts (ud0) and ions (ui0) are observed to play very important role to form dust-ion acoustic compressive and rarefactive KdV solitons. Remarkably, some initial streaming of dust (ud0) are found to be instrumental for both compressive and rarefactive KdV solitons in a short range of Zd separating both kinds by some asymptotic lines. Also, the presence of low dust charges and lower ion streaming, compressive and rarefactive KdV solitons of either concave or convex characters are shown to reflect. For the higher streaming of mobile dusts, the amplitudes of the rarefactive KdV solitons characteristically changes from higher to lower showing convex character for this plasma model. A rigorous theoretical investigation has been made to show how the number of dust charge contained in a dust particle (Zd) drastically change the amplitudes of the compressive and rarefactive KdV solitons.
Deformation of quark stars under strong internal magnetic fields
Authors: Rizaldy R. , Sulaksono A.
Published: October 2019

The pulsar detector has observed the existence of a strong magnetic field on compact stars. So much we can learn from this observation, one of them is the deformation of a compact star under strong magnetic fields. In this note, we study the deformation of quark stars due to a magnetic field. Note that quark stars and neutron stars have a fundamental difference in their equation of states such as the composition and crusts. Here, we used two equation of states of quark matter, i.e., CIDDM model with the scalar and with vector Coulomb terms included [1]. In both equation of states, we vary the magnetic field value in the center of the star to see how the internal magnetic field affects the shape of the quark star.
The effective dark energy in brane universe
Authors: Bansawang B J , Gazali Yunus M N , Sutiono Azwar , Surungan Tasrief
Published: October 2019

We study the dynamical system of braneworld cosmology with the effective cosmological constant as the effective dark energy on brane universe. Firstly we introduce several scenarios of braneworld model then derive the effective EFE on the brane which reduced at low energy limit. Next, we discuss the FRW cosmological model in braneworld scenario considered in static and non-closed system. In the dynamical study of cosmology, we assume the equation of state of dark energy varies with time and can be parameterized as a function of scale factor of the universe. Using the dynamical system approach, we describe the evolution of brane universe with non-vanishing NCC/BCC term. In this study, we investigate the effects of the presence of NCC/BCC perturbations in brane universe. Finally, we discuss the NCC/BCC perturbations in the late-time cosmic acceleration when the dark energy contribution is ΩΛ ≃ 0.72.
Temporal statistics of residual wavefront variance of an adaptive optics system
Authors: Huang Jian , Zhou Hong , Yang Jinsheng , Liu Chao , Xian Hao
Published: October 2019

We present the probability density function (PDF) for the residual wavefront variance of an adaptive optics system that includes control error, the fitting error of a deformable mirror, and Hartmann sensor detecting noise. The PDF is directly connected to adaptive optics system parameters and the spatiotemporal strength parameters of atmospheric turbulence, and it can be described as a generalized Chi square distribution. Our results provide a more precise theory for adaptive optics systems compared to the current theory based on the ensemble average. Thus, this study can contribute to the development of high-resolution and high-stability adaptive optics systems for astronomy and optical communications in the atmosphere.
Residually finite rationally solvable groups and virtual fibring
Authors: Kielak Dawid
Published: October 2019

We show that a non-trivial finitely generated residually finite rationally solvable (or RFRS) group

G
G

is virtually fibred, in the sense that it admits a virtual surjection to

Z

\mathbb {Z}

with a finitely generated kernel, if and only if the first

L
2

L^2

-Betti number of

G
G

vanishes. This generalises (and gives a new proof of) the analogous result of Ian Agol for fundamental groups of

3
3

-manifolds.
On free subsemigroups of associative algebras
Authors: Letzter Edward
Published: October 2019

In 1992, following earlier conjectures of Lichtman and Makar-Limanov, Klein conjectured that a noncommutative domain must contain a free, multiplicative, noncyclic subsemigroup. He verified the conjecture when the center is uncountable. In this note we consider the existence (or not) of free subsemigroups in associative

k
k

-algebras

R
R

, where

k
k

is a field not algebraic over a finite subfield. We show that

R
R

contains a free noncyclic subsemigroup in the following cases: (1)

R
R

satisfies a polynomial identity and is noncommutative modulo its prime radical. (2)

R
R

has at least one nonartinian primitive subquotient. (3)

k
k

is uncountable and

R
R

is noncommutative modulo its Jacobson radical. In particular, (1) and (2) verify Klein’s conjecture for numerous well-known classes of domains, over countable fields, not covered in the prior literature.
The weak sigma-attractor for the semi-dissipative 2D Boussinesq system
Authors: He Jinfang , Sun Chunyou
Published: October 2019

In this paper, we obtain the attraction properties for the velocity variable of the 2D Boussinesq equations with viscosity and without heat diffusion in the sense of the strong topology of

V
V

and prove that the weak sigma-attractor has a pancake-like structure, which answer partly some questions arising in Biswas et al. [Ann. Inst. H. Poincaré Anal. Non Linéaire 34 (2017), pp. 381–405] and enrich the structure of the weak sigma-attractor.
A note on Non-Noetherian Cohen-Macaulay rings
Authors: Kim Youngsu , Walker Andrew
Published: October 2019

In this note, we study the Cohen-Macaulayness of non-Noetherian rings. We show that Hochster’s celebrated theorem that a finitely generated normal semigroup ring is Cohen-Macaulay does not extend to non-Noetherian rings. We also show that for any valuation domain

V
V

of finite Krull dimension,

V
[
x
]

V[x]

is Cohen-Macaulay in the sense of Hamilton-Marley.
On the structure of the Sally module and the second normal Hilbert coefficient
Authors: Masuti Shreedevi , Ozeki Kazuho , Rossi Maria Evelina , Truong Hoang
Published: October 2019

The Hilbert coefficients of the normal filtration give important geometric information on the base ring like the pseudo-rationality. The Sally module was introduced by W.V. Vasconcelos and it is useful to connect the Hilbert coefficients to the homological properties of the associated graded module of a Noetherian filtration. In this paper we give a complete structure of the Sally module in the case the second normal Hilbert coefficient attains almost minimal value in an analytically unramified Cohen-Macaulay local ring. As a consequence, in this case we present a complete description of the Hilbert function of the associated graded ring of the normal filtration. A deep analysis of the vanishing of the third normal Hilbert coefficient has been necessary. This study is related to a longstanding conjecture stated by S. Itoh.
Operators polynomially isometric to a normal operator
Authors: Marcoux Laurent , Zhang Yuanhang
Published: October 2019

Let

H

\mathcal {H}

be a complex, separable Hilbert space and let

B

(

H

)

\mathcal {B}(\mathcal {H})

denote the algebra of all bounded linear operators acting on

H

\mathcal {H}

. Given a unitarily-invariant norm

‖
⋅

‖
u

\| \cdot \|_u

on

B

(

H

)

\mathcal {B}(\mathcal {H})

and two linear operators

A
A

and

B
B

in

B

(

H

)

\mathcal {B}(\mathcal {H})

, we shall say that

A
A

and

B
B

are polynomially isometric relative to

‖
⋅

‖
u

\| \cdot \|_u

if

‖
p
(
A
)

‖
u

=
‖
p
(
B
)

‖
u

\| p(A) \|_u = \| p(B) \|_u

for all polynomials

p
p

. In this paper, we examine to what extent an operator

A
A

being polynomially isometric to a normal operator

N
N

implies that

A
A

is itself normal. More explicitly, we first show that if

‖
⋅

‖
u

\| \cdot \|_u

is any unitarily-invariant norm on

M

n

(

C

)

\mathbb {M}_n(\mathbb {C})

, if

A
,
N
∈

M

n

(

C

)

A, N \in \mathbb {M}_n(\mathbb {C})

are polynomially isometric and

N
N

is normal, then

A
A

is normal. We then extend this result to the infinite-dimensional setting by showing that if

A
,
N
∈

B

(

H

)

A, N \in \mathcal {B}(\mathcal {H})

are polynomially isometric relative to the operator norm and

N
N

is a normal operator whose spectrum neither disconnects the plane nor has interior, then

A
A

is normal, while if the spectrum of

N
N

is not of this form, then there always exists a nonnormal operator

B
B

such that

B
B

and

N
N

are polynomially isometric. Finally, we show that if

A
A

and

N
N

are compact operators with

N
N

normal, and if

A
A

and

N
N

are polynomially isometric with respect to the

(
c
,
p
)

(c,p)

-norm studied by Chan, Li, and Tu, then

A
A

is again normal.
Inhomogeneous Strichartz estimatesin some critical cases
Authors: Bez Neal , Cunanan Jayson , Lee Sanghyuk
Published: October 2019

Strong-type inhomogeneous Strichartz estimates are shown to be false for the wave equation outside the so-called acceptable region. On a critical line where the acceptability condition marginally fails, we prove substitute estimates with a weak-type norm in the temporal variable. We achieve this by establishing such weak-type inhomogeneous Strichartz estimates in an abstract setting. The application to the wave equation rests on a slightly stronger form of the standard dispersive estimate in terms of certain Besov spaces.
On the Lie algebra structure of 𝐻𝐻¹(𝐴) of a finite-dimensional algebra 𝐴
Authors: Linckelmann Markus , Rubio y Degrassi Lleonard
Published: October 2019

Let

A
A

be a split finite-dimensional associative unital algebra over a field. The first main result of this note shows that if the

Ext
\operatorname {Ext}

-quiver of

A
A

is a simple directed graph, then

H

H
1

(
A
)

H\!H^1(A)

is a solvable Lie algebra. The second main result shows that if the

Ext
\operatorname {Ext}

-quiver of

A
A

has no loops and at most two parallel arrows in any direction, and if

H

H
1

(
A
)

H\!H^1(A)

is a simple Lie algebra, then

char
⁡
(
k
)
≠

\operatorname {char}(k)\neq

2
2

and

H

H
1

(
A
)
≅

H\!H^1(A)\cong

s
l

2

⁡
(
k
)

\operatorname {\mathfrak {sl}}_2(k)

. The third result investigates symmetric algebras with a quiver which has a vertex with a single loop.
A class of nilpotent Lie algebras whose center acts nontrivially in cohomology
Authors: Cairns Grant , Jessup Barry , Nikolayevsky Yuri
Published: October 2019

We show that the central representation is nontrivial for all one-dimensional central extensions of nilpotent Lie algebras possessing a codimension one abelian ideal.
On the tropical discs counting on elliptic K3 surfaces with general singular fibres
Authors: Lin Yu-Shen
Published: October 2019

Using Lagrangian Floer theory, we study the tropical geometry of K3 surfaces with more general singular fibres other than simple nodal curves. In particular, we give the local models for the types

I
n

I_n

,

I
I

II

,

I
I
I

III

and

I
V

IV

singular fibres in the Kodaira classification. This generalizes the correspondence theorem in “Correspondence theorem between holomorphic discs and tropical discs on K3 surfaces”, arXiv:1703.00411 between open Gromov-Witten invariants/tropical discs counting to these cases.
Descents of unipotent representations of finite unitary groups
Authors: Liu Dongwen , Wang Zhicheng
Published: October 2019

Inspired by the Gan-Gross-Prasad conjecture and the descent problem for classical groups, in this paper we study the descents of unipotent representations of unitary groups over finite fields. We give the first descents of unipotent representations explicitly, which are unipotent as well. Our results include both the Bessel case and Fourier-Jacobi case, which are related via theta correspondence.
Health Status and Quality of Life of Women Seeking Infertility Treatments in Baluchistan, Pakistan
Authors: Hassan Sehar-Un-Nisa , Siddiqui Salma , Friedman Bruce D
Published: October 2019

Obstacles in health-care service delivery and attitudinal barriers contribute to women being vulnerable to increased social and psychological costs resulting from infertility in developing countries. The present study uses quantitative data to examine women’s infertility experiences and its impact on their quality of life (QoL). Women seeking infertility treatments from reproductive health-care centres in Baluchistan, Pakistan participated in the study. Findings demonstrate that infertility has a significant influence on women’s health and QoL, irrespective of age, education, years in marriage, economic background and types of infertility. Given that women also experience several additional social consequences of infertility, such as a husband’s second marriage, fear of divorce, intimate-partner violence, social stigma and family pressure for a male child, social workers must comprehend the economic, social and cultural factors associated with infertility and its influence on health status and QoL. Findings have implications for prioritising an integrative intervention plan at the micro, mezzo and macro levels of practice to address the gaps and inequalities in the health care of infertile couples.
The Information Behaviour of Social Workers: Needs, Seeking, Acquiring and Using Information in Practice
Authors: Flanagan Niamh
Published: October 2019

In the debate about what informs social work practice, research remains the dominant discourse. However, the relationship between research and social work practice has always been an uneasy one, arguably passed from other clinical disciplines without resizing to fit social work. Even as social work research matures as a discipline it represents one element in a much broader composite which informs practice. This article takes a unique step back from the traditional research-practice discourse and examines the broader information landscape of social work practice, asking how practitioners inform their practice, rather than how research informs practice. This study explores the information needs that prompt practitioners to search for information, the strategies they employ, their acquisition of information and the uses to which the information is put. This study aims to elucidate the information behaviour with a view to improving dissemination and use. Findings demonstrate that the social work information base is substantially broader than has been suggested. Practitioners employ a pragmatic palette of strategies to navigate the breadth of information that supports practice, from research through to knowledge sharing. This article proposes that a pragmatic framework of information behaviour is required to accurately reflect the information behaviour of social workers.