bluuebunny/crossref_metadata_2025 huggingface dataset:
Redescription and molecular analysis of Neoechinorhynchus (Neoechinorhynchus) johnii Yamaguti, 1939 (Acanthocephala, Neoechinorhynchidae) from the Pacific Ocean off Vietnam
Authors: Amin Omar M. , Chaudhary Anshu , Heckmann Richard , Ha Nguyen V. , Singh Hridaya S.
Published: July 2019

Neoechinorhynchus (Neoechinorhynchus) johnii Yamaguti, 1939 is redescribed from Eleutheronema tetradactylum (Polynemidae), Johnius carouna (Sciaenidae), Johnius sp., and Otolithes ruber (Sciaenidae) along the north and south coasts of Vietnam. Our description completes missing and inadequate information in the original descriptions and line drawings from Johnius goma in Japan and from Pseudosciaena diacanthus in the Indian Ocean. We add new information documented by scanning electron microscopy (SEM) and photomicroscopy, and explore the wide morphological diversity attributed to host species. The redescription includes: worms cylindrical with round proboscis with prominent apical organ, and large anterior hooks distant from small middle and posterior hooks; neck longer than the proboscis, nucleated lemnisci subequal, and receptacle with large basal triangulate cephalic ganglion and attached para-receptacle structure (PRS); male reproductive system in posterior half of trunk; adult females with introvert genital vestibule; and eggs spherical or rectangular. Gallium cuts and X-ray scans of hooks show high concentrations of sulfur on edge layer aiding in forming hardened calcium phosphate apatite of that layer with calcium and phosphorus in higher concentration in central part of hook. Molecular results consistently yielded a strongly supported distinct clade for the Neoechinorhynchus species from Vietnam for both 18S gene and the ITS1-5.8S-ITS2 region of ribosomal RNA. Phylogenetic analysis demonstrated that N. johnii occupies a separate position in the trees, probably indicating an Asian origin of this species.
The phylogenetic position ofAnacanthorus(Monogenea, Dactylogyridae) parasitizing Brazilian serrasalmids (Characiformes)
Authors: Moreira Juliana , Luque José L. , Šimková Andrea
Published: July 2019

Anacanthorus(Anacanthorinae) is one of the most speciose and common genera of neotropical monogeneans, yet there are still many gaps in our knowledge concerning their diversity and phylogeny. We performed phylogenetic analyses of molecular sequences in order to investigate the phylogenetic position within the Dactylogyridae ofAnacanthorusspp. infesting serrasalmids from two Brazilian river basins. Sequences of partial 28S rDNA obtained for nine species ofAnacanthorusandMymarothecium viatorumparasitizing serrasalmids and the published sequences of other members of the Dactylogyridae were included in the phylogenetic reconstruction. Phylogenetic analyses supported the monophyly of anacanthorine monogeneans. The Anacanthorinae (represented in this study byAnacanthorusspp.) formed a monophyletic group included in a large clade together with a group of solely freshwater Ancyrocephalinae and species of the Ancylodiscoidinae.Mymarothecium viatorum(Ancyrocephalinae) was placed within the clade of freshwater Ancyrocephalinae. The phylogenetic analyses indicated that the relationships among species ofAnacanthorusreflect those of their serrasalmid hosts: the first subgroup includes a species specific to hosts assigned toPiaractus, a member of the “pacus” lineage; the second subgroup includes a species parasitizing the “Myleus-like pacus” lineage; and the third subgroup includes species parasitizing the lineage of the “true piranhas”. We suggest thatAnacanthorusand their serrasalmid hosts can be considered a useful model to assess host-parasite biogeography and coevolution in the neotropics. However, future studies focusing on a wider spectrum of host species and their specificAnacanthorusspp. are needed in order to investigate coevolution in this highly diversified system.
Performance evaluation of portfolios with fuzzy returns
Authors: Zhou Zhongbao , Chen Enming , Xiao Helu , Ren Tiantian , Jin Qianying
Published: July 2019

The existing literature on DEA (Data Envelopment Analysis) for evaluating fuzzy portfolios usually takes risk as an input and return as an output. This assumption is actually not congruent with the real investment process, where the input is the initial wealth and the output is the corresponding terminal wealth. As for the risk and return, which are essentially two indicators derived from the terminal wealth, both should be regarded as outputs. In addition, few studies have employed the diversification model (nonlinear DEA) to estimate the fuzzy portfolio efficiency (PE), despite the fact that there are many studies available within the framework of classical probability theory. Further, the relationship between DEA and diversification models needs to be defined. In this paper, we take the initial wealth as an input, while the return and risk of terminal wealth are taken as desirable and undesirable outputs, respectively. We construct different evaluation models under the fuzzy portfolio framework. The relationships among the evaluation model based on a real frontier, the diversification model and the DEA model are investigated. We show the convergence of the diversification and DEA models under the fuzzy theory framework. Some simulations as well as empirical analysis are presented to further verify the effectiveness of the proposed models. Finally, we check the robustness of the evaluation results by using the bootstrap re-sampling approach.
Hochfunktionaler Autismus bei Erwachsenen
Authors: van Elst Ludger Tebartz
Published: July 2019

Die hochfunktionalen Autismus-Spektrum-Störungen stellen eine wichtige Differenzialdiagnose nicht nur in der Kinder- und Jugendpsychiatrie, sondern auch in der Erwachsenenpsychiatrie und durchaus auch für die Psychotherapie dar. Obwohl das Thema insbesondere in der Wissenschaft eine stark zunehmende Beachtung findet, ist es im klinischen Alltag der psychiatrisch-psychotherapeutischen Versorgungsrealität immer noch kaum angekommen.
The role of the atomic decoherence-free subalgebra in the study of quantum Markov semigroups
Authors: Fagnola Franco , Sasso Emanuela , Umanità Veronica
Published: July 2019

We show that for a Quantum Markov Semigroup (QMS) with a faithful normal invariant state, atomicity of the decoherence-free subalgebra and environmental decoherence are equivalent. Moreover, we prove that the predual of the decoherence-free subalgebra is isometrically isomorphic to the subspace of reversible states. We also describe, in an explicit and constructive way, the relationship between the decoherence-free subalgebra and the fixed point subalgebra.
Generators of rank 2 cluster algebras of affine types via linearization of seed mutations
Authors: Nobe Atsushi
Published: July 2019

From the viewpoint of integrable systems on algebraic curves, we discuss linearization of birational maps arising from the seed mutations of types A1(1) and A2(2), which enables us to construct the set of all cluster variables generating the corresponding cluster algebras. These birational maps induce discrete integrable systems on algebraic curves referred to as the types of the seed mutations from which they are arising. The invariant curve of type A1(1) is a conic, while the one of type A2(2) is a singular quartic curve. By applying the blowing-up of the singular quartic curve, the discrete integrable system of type A2(2) on the singular curve is transformed into the one on the conic, the invariant curve of type A1(1). We show that both the discrete integrable systems of types A1(1) and A2(2) commute with each other on the conic, the common invariant curve. We moreover show that these integrable systems are simultaneously linearized by means of the conserved quantities and their general solutions are obtained. By using the general solutions, we construct the sets of all cluster variables generating the cluster algebras of types A1(1) and A2(2).
Recent advances in microfluidic methods in cancer liquid biopsy
Authors: Iliescu Florina S. , Poenar Daniel P. , Yu Fang , Ni Ming , Chan Kiat Hwa , Cima Irina , Taylor Hayden K. , Cima Igor , Iliescu Ciprian
Published: July 2019

Early cancer detection, its monitoring, and therapeutical prediction are highly valuable, though extremely challenging targets in oncology. Significant progress has been made recently, resulting in a group of devices and techniques that are now capable of successfully detecting, interpreting, and monitoring cancer biomarkers in body fluids. Precise information about malignancies can be obtained from liquid biopsies by isolating and analyzing circulating tumor cells (CTCs) or nucleic acids, tumor-derived vesicles or proteins, and metabolites. The current work provides a general overview of the latest on-chip technological developments for cancer liquid biopsy. Current challenges for their translation and their application in various clinical settings are discussed. Microfluidic solutions for each set of biomarkers are compared, and a global overview of the major trends and ongoing research challenges is given. A detailed analysis of the microfluidic isolation of CTCs with recent efforts that aimed at increasing purity and capture efficiency is provided as well. Although CTCs have been the focus of a vast microfluidic research effort as the key element for obtaining relevant information, important clinical insights can also be achieved from alternative biomarkers, such as classical protein biomarkers, exosomes, or circulating-free nucleic acids. Finally, while most work has been devoted to the analysis of blood-based biomarkers, we highlight the less explored potential of urine as an ideal source of molecular cancer biomarkers for point-of-care lab-on-chip devices.
An integration design of gas exchange, bubble separation, and flow control in a space cell culture system on board the SJ-10 satellite
Authors: Sun Shujin , Wang Chengzhi , Bi Yuzhen , Li Ning , Lü Dongyuan , Chen Qin , Chen Juan , Long Mian
Published: July 2019

Pathophysiological changes of astronauts under space microgravity involve complex factors and require an integrative perspective to fully understand the mechanisms. The readouts from space cell biology experiments strongly depend on the hardware and especially the cell bioreactor that is used in distinct spacecraft. Herein, a specialized cell culture bioreactor is designed for culturing mammalian cells on board the SJ-10 satellite. This hardware focuses mainly on satisfying the requirements of gas exchange, bubble separation, and flow control, as well as their functional and structural integration on cell culture within the technical and environmental constraints of the spacecraft platform under microgravity. A passive bubble separator is constructed and is connected in series to an individual cell culture chamber to remove the bubbles that were produced in orbit during cell growth. A moderate flow rate is preset to provide sufficient mass transfer and low shear stress in a well-designed flow circuit. Together with other modules of temperature control, in situ microscopic imaging, and online imaging acquisition, this novel space cell culture system is successfully used to culture human endothelial cells and rat bone marrow-derived mesenchymal stem cells in the SJ-10 mission. The advantages and shortcomings of the integration design are discussed for this type of the hardware.
Design of a lightweight magnetizer to enable a portable circumferential magnetic flux leakage detection system
Authors: Pham Hong Quang , Le Van Sy , Vu Minh Hung , Doan Duy Tuan , Tran Quang Hung
Published: July 2019

We proposed a lightweight magnetizer toward the realization of a portable circumferential magnetic flux leakage (MFL) inspection tool for the detection of longitudinal defects with a linear motion between pipes and the inspection tool. The proposed magnetizer consists of four permanent magnetic poles constructing a configuration in which the like poles are separated by a θ angle ranging from 30° to 60° and the opposite poles are separated by a supplemental angle of θ. The distribution of the magnetic field generated by this magnetizer and caused by defects was studied by finite element methods as well as by experimental measurements. The results reveal that the new magnetizer has advantages of high amplitude and good uniformity of magnetic field over the state-of-the-art ones with configurations of two facing poles or quadrupole geometries. With the new magnetizer, the theoretical and experimental results show that the magnetization in the pipe increases slightly with the θ angle, but the uniformity of magnetization in the pipe and the magnetic field on the surface of pipe decrease dramatically with this angle. So, the optimum angle θ is proposed at around 30°–40°. The finite element calculation and the measurements of the MFL signal caused by artificial defects evidence the capabilities in detecting shallow longitudinal defects of the MFL inspection tool with our novel magnetizer.
Every entangled state provides an advantage in classical communication
Authors: Bäuml S. , Winter A. , Yang D.
Published: July 2019

We investigate the use of noisy entanglement as a resource in classical communication via a quantum channel. In particular, we are interested in the question whether for any entangled state, including bound entangled states, there exists a quantum channel, the classical capacity of which can be increased by providing the state as an additional resource. We partially answer this question by showing, for any entangled state, the existence of a quantum memory channel, the feedback-assisted classical capacity with product encodings of which can be increased by using the state as a resource. Using a different (memoryless) channel construction, we also provide a sufficient entropic condition for an advantage in classical communication (without feedback and for general encodings) and thus provide an example of a state that is not distillable by means of one-way local operations and classical communication but can provide an advantage in the classical capacity of a number of quantum channels. As separable states cannot provide an advantage in classical communication, our condition also provides an entropic entanglement witness.
Intrinsic flow and tearing mode rotation in the RFP during improved confinement
Authors: Craig D. , Tan E. H. , Schott B. , Anderson J. K. , Boguski J. , Den Hartog D. J. , Nishizawa T. , Nornberg M. D. , Xing Z. A.
Published: July 2019

We use charge exchange recombination spectroscopy to make the first localized measurements of impurity ion flow velocity profiles in the reversed field pinch. Measurements in improved confinement plasmas reveal an intrinsic flow profile that is peaked on the axis and mostly parallel to the equilibrium magnetic field. The toroidal flow decreases in time at off-axis locations where tearing modes are resonant, giving rise to a highly sheared flow profile near the axis. The tearing mode phase velocity correlates strongly with toroidal flow near the resonant surface and weakly with flow in other locations, providing an opportunity to verify the commonly held assumption that the plasma and mode move together at the resonant surface. Mechanisms for the observed momentum loss during the improved confinement period are evaluated, and it is found that eddy currents in the conducting shell caused by the rotation of the dominant tearing mode dominate over other losses.
A transient-electroluminescence study on perovskite light-emitting diodes
Authors: Xu Mengmeng , Peng Qiming , Zou Wei , Gu Lianghui , Xu Lei , Cheng Lu , He Yarong , Yang Ming , Wang Nana , Huang Wei , Wang Jianpu
Published: July 2019

We carried out transient-electroluminescence (Tr-EL) studies on multiple-quantum-well (MQW)-based perovskite light-emitting diodes (PeLEDs). The Tr-EL shows a short onset time (τd ∼ 0.1 μs) and rising time (τr ∼ 0.15 μs), demonstrating high carrier mobility in the MQW perovskites. The electron-mobility in the MQW perovskites was evaluated to be on the order of 10−5 cm2 V−1 s−1. When the pulses are turned off, the Tr-EL decays to zero in around 1 μs, indicating a low trap density in the MQW perovskites which was estimated to be on the order of 1015 cm−3. Besides, the Tr-EL enables us to study the EL properties of PeLEDs at intense current densities, with the results showing that both the “Auger” recombination and “Joule” heating are the main causes of the efficiency droop at current densities of tens of ampere per centimeter square.
Unified modeling of both resonant and non-resonant neoclassical transport under non-axisymmetric magnetic perturbations in tokamaks
Authors: Sun Y. , Li X. , He K. , Shaing K. C.
Published: July 2019

A numerical model for neoclassical transport under nonaxisymmetric magnetic perturbations in low collisionality plasmas in tokamaks is developed. To take into account bounce-drift resonances and magnetic drift effects, a Fourier decomposition of the drift kinetic equation in new coordinates, rather than bounce average of it, is employed. A pitch angle scattering collisional operator is used to keep accuracy in the nonresonant regimes or resonant plateau regimes with resonant pitch near pitch space boundaries. Full toroidal geometry effects are also included to increase the accuracy in the modeling of neoclassical transport in the resonant regimes. Neoclassical transport in the most important collisionless regimes, including resonant super-banana plateau and bounce-drift resonances regimes, nonresonant 1/ν and ν−ν regimes, and the transitions between them, can be modeled simultaneously in this model by numerically solving the drift kinetic equation. By application to the neoclassical toroidal viscosity modeling in one discharge in the EAST tokamak, it is found that the bounce-drift resonances dominate the contributions near the plasma core where the plasma E→×B→ drift frequency is close to the bounce frequency, while the precessional resonance dominates the contribution near the edge pedestal top where the E→×B→ drift frequency is close to zero.
Modal learning displacement–strain transformation
Authors: Deng Huaxia , Zhang Haicong , Wang Jun , Zhang Jin , Ma Mengchao , Zhong Xiang
Published: July 2019

The displacement–strain transformation is essential for revealing the internal mechanics of structures and developing strain measurement methods. This transformation typically depends on the environment of the structure. In contrast to the traditional invariant transformation, this paper proposes a method to obtain a variable displacement–strain transformation by self-learning of the modal parameters of the structure in operation. The beam experimental results demonstrate that the transformation is able to take account of different forms of excitation and to obtain strain measurements under sinusoidal and random excitation with up to 99.82% and 99.70% accuracy, respectively. Moreover, these results indicate that the proposed displacement–strain transformation is able to take account of the environmental conditions encountered in practical situations more consistently than conventional approaches. The introduction of a modal-learning displacement–strain transformation in the proposed approach provides a welcome boost to the development of strain measurement methods.
Photoluminescence-based detection of mechanical defects in multijunction solar cells
Authors: Zimmermann Claus G.
Published: July 2019

Mechanical solar cell defects give rise to a characteristic contrast in luminescence imaging. In multijunction cell architectures, the current in each subcell can be adjusted individually in photoluminescence imaging in contrast to electroluminescence imaging. The contrast formation under these conditions is derived theoretically. The image contrast of a defect recorded by illuminating and imaging one specific subcell can be reversed by illuminating the adjacent subcell in addition. This provides a convenient method to eliminate all background contrast by subtracting both images, resulting in an improved visibility of defects. This is demonstrated experimentally for the top cell of Ga0.5In0.5P/GaAs/Ge triple junction solar cells.
Control of solitary-drift-wave formation by radial density gradient in laboratory magnetized cylindrical plasma
Authors: Chang Feng-Jen , Kawamori Eiichirou
Published: July 2019

Solitary drift waves (SDWs) in magnetized plasmas were discovered and then first investigated by experiment and numerical simulation by the Kyushu University group [i.e., H. Arakawa et al., Plasma Phys. Controlled Fusion 52, 105009 (2010)]. However, the formation mechanisms of SDWs still await thorough examination. Our work experimentally identifies a clear transition from turbulent drift waves (DWs) to SDWs for varied radial gradients in background density, which is in agreement with the preceding numerical simulations [M. Sasaki et al., Phys. Plasmas 22, 032315 (2015)]. The formation of SDWs is accompanied by a significant growth in the total fluctuation level and three-wave phase coupling between the constitutive harmonic modes. A subsequent saturation in the total fluctuation level and intensity of three-wave coupling when further increasing the density gradient is witnessed for the first time. The transition from turbulent DWs to SDWs is also characterized by an increase in the radial wavelength of the DWs. The SDW is considered a meso- (or macro-) scale ordered structure nonlinearly generated by turbulent DWs. Our work on SDW generation indicates that this phenomenon in magnetized plasmas is a universal rather than a device-dependent phenomenon.
Crystallographic orientation of orthorhombic aragonite using reflection generalized ellipsometry
Authors: Jellison G. E. , Leonard D. N. , Anovitz L. M. , Cheshire M. C. , Specht E. D. , Rosseel T. M.
Published: July 2019

The 2-modulator generalized ellipsometry microscope (2-MGEM) has been used to study a natural crystal of aragonite. Like its polymorph calcite, aragonite has a large refractive index difference between light polarized parallel to the c-axis and light polarized perpendicular to the c-axis. Unlike calcite, aragonite is orthorhombic, so there is also a very small difference between the refractive indices polarized along the a- and b-directions. As a result, it is not possible to use the 2-MGEM to obtain a definitive map of the optic axis directions of a sample as was possible with calcite, but it is possible to determine approximately the orientation of the c-axis with respect to the surface normal. If the c-axis is in the sample surface plane, it is possible to measure very small deviations of the c-axis direction with an accuracy of ∼0.2°. If the c-axis is oriented normal to the sample surface, 2-MGEM data can be used to identify different crystallites due to rotations about the c-axis. For comparison, the orientations of some of the crystallites have also been measured using X-ray Laue and electron beam backscatter diffraction. In addition, spectroscopic generalized ellipsometry measurements have been used to determine the refractive indices of aragonite.
Impact of a small change in growth temperature on the tail states of GaAsBi
Authors: Kakuyama Kyohei , Hasegawa Sho , Nishinaka Hiroyuki , Yoshimoto Masahiro
Published: July 2019

The influence of growth temperature (Tsub) on the tail states of GaAs1−xBix (0 ≦ x ≦ 0.05) was studied via its sub-bandgap absorption and photoluminescence (PL) characteristics. The Urbach energy (E0) was estimated from the spectral response of the photocurrent of pin GaAs1−xBix photodiodes grown at a low Tsub of 360 °C and a high Tsub of 380 °C. The E0 of GaAs1−xBix is greater than that of GaAs. Once Bi atoms are incorporated, the tail states are formed probably due to Bi atom clustering. The E0 of the GaAs1−xBix sample at Tsub = 380 °C was smaller than the E0 of the sample grown at Tsub = 360 °C; therefore, the formation of the tail states was suppressed by a small increase in the Tsub of 20 °C. At a Tsub of 380 °C, the E0 decreases as the GaBi molar fraction increases. The increase in the Bi flux upon an increase in the GaBi molar fraction may enhance the surfactant effect of the Bi atoms, resulting in an enhancement in the migration of adsorbed atoms at Tsub = 380 °C and a reduction in the tail states. The full-width at half-maximum of the PL peak and the characteristic energy of the temperature dependence of the PL peak energy confirmed the same Tsub tendency of the tail states. The small increase in the Tsub of 20 °C suppressed the inhomogeneous incorporation of Bi atoms into GaAs1−xBix, such as an atomic-scale Bi clustering and the formation of tail states.
Computational discovery of hard and superhard materials
Authors: Kvashnin Alexander G. , Allahyari Zahed , Oganov Artem R.
Published: July 2019

Computational materials discovery is a booming field of science, which helps in predicting new unexpected materials with optimal combinations of various physical properties. Going beyond the targeted search for new materials within prespecified systems, the recently developed method, Mendelevian search, allows one to look for materials with the desired properties across the entire Periodic Table, indicating possibly superhard (or other) materials that could be obtained experimentally. From this viewpoint, we discuss the recently developed methods for crystal structure prediction and empirical models of Vickers hardness and fracture toughness that allow fast screening for materials with optimal mechanical properties. We also discuss the results of the computational search for hard and superhard materials obtained in the last few years using these novel approaches and present a “treasure map” of hard and superhard materials, which summarizes known and predicted materials and points to promising future directions of superhard materials discovery.
Trapping of metallic nanoparticles under the free surface of superfluid helium in a static electric field
Authors: Moroshkin P. , Leiderer P. , Möller Th. B. , Kono K.
Published: July 2019

Electrically charged metallic microparticles and nanoparticles have been trapped under a free surface of superfluid 4He in a vertical static electric field. We report the details of the trapping technique and the observed dynamics of the trapped particles moving along the surface and driven by surface waves, by a static horizontal electric field, and by a thermal counterflow within the surface layer of liquid He.
Effects of trapping site on the spectroscopy of 1P1 excited group 12 metal atoms in rare gas matrices
Authors: Lara-Moreno M. , Alvarez-Hernández J. , Negrín-Yuvero H. , McCaffrey J. G. , Rojas-Lorenzo G.
Published: July 2019

A molecular dynamics deposition model has been used to simulate the growth of rare gas matrices doped with atoms of the group 12 elements zinc, cadmium and mercury. This study investigates the sites occupied by Zn, Cd and Hg metal atoms when isolated in the solid rare gases. To probe the results, the resonance 1P1←1S0 transitions of the matrix-isolated metal atoms were calculated and compared with the recorded spectra of the M/RG solids. The theoretical spectroscopy obtained in this work was generated using the molecular dynamics with quantum transitions method. In Ne matrices the metal atoms preferably occupy tetra- and hexa-vacancy sites while in the case of Xe matrices, only the single vacancy site is formed. For Ar and Kr matrices Zn but especially Cd can be trapped in tetra- and hexa-vacancy sites in addition to single-vacancy sites, while Hg atoms show exclusive occupancy in single vacancy sites.
New ion desorption mechanism from rare gas solids by multiply charged ion impacts
Authors: Ban K. , Akiwa M. , Ueta H. , Tachibana T. , Hirayama T.
Published: July 2019

This study measured the absolute ion desorption yield from the surface of solid Ne and Ar by low-energy Neq+ (q = 1–4), Arq+ (q = 1–6), and Krq+ (q = 2–6) ion impacts. Results revealed the dependence of ion desorption yield on the potential and the kinetic energies of the incident ions, as well as its linear proportionality with the former. Present results could not be explained by existing models for ion desorption from insulator surfaces. We proposed a new mechanism of ion desorption that considers the contribution of both energy types to ion desorption.
Evolution of the transverse electrical resistivity of YBa2Cu3O7–δ single crystals under irradiation with high-energy electrons
Authors: Khadzhai G. Ya. , Litvinov Yu. V. , Vovk R. V.
Published: July 2019

The effect of irradiation with high-energy electrons on the transverse electrical resistivity of YBa2Cu3O7–δ single crystals with a high degree of perfection that are optimally doped with oxygen is considered. This irradiation creates macroscopic regions oriented along the layers in the sample, which are characterized by oxygen deficiency, leading to variable-range hopping transverse conductivity. An increase in the dose of irradiation leads to a decrease in the region of localization of charge carriers.
Experimental observation of anomalies in the electrical, magnetic, and galvanomagnetic properties of cobalt-based Heusler alloys with varying transition elements
Authors: Perevozchikova Yu. A. , Semiannikova A. A. , Domozhirova A. N. , Terentev P. B. , Marchenkova E. B. , Patrakov E. I. , Eisterer M. , Korenistov P. S. , Marchenkov V. V.
Published: July 2019

The residual resistivity, Hall effect, and magnetization of Co2YSi (Y = Ti, V, Cr, Mn, Fe, Co, Ni) Heusler alloys were considered at T = 4.2 K and in fields up to 100 kOe. It is shown that as the number of valence electrons z ranges from 26 to 32, significant changes in the residual resistivity ρ0, magnetization Ms, sign and magnitude of the normal R0 and anomalous RS Hall effect coefficients are observed during the transition from Co2TiSi to Co2NiSi. It is established that there is a clear correlation between the values ρ0, R0, RS and Ms, depending on the number z, which can be associated with the appearance of a half-metal ferromagnetic state and/or spin gapless semiconductor. As z changes, the anomalous Hall effect coefficient has a power-law dependence on the residual electrical resistivity with an exponent of k = 3.1, which diverges with existing theories but agrees well with the experimental data obtained earlier for similar half-metallic ferromagnetic Heusler alloys.
Nonlinear resonant tunneling as mechanism of cool electrons filtration
Authors: Ermakov V. N. , Ponezha E. A.
Published: July 2019

The paper is devoted to the explanation of the effect of suppressing the temperature distribution of the current carriers in the tunneling device where a nanoparticle embedded in a dielectric matrix served as a quantum dot (QD). Due to a spatial confinement the quantization of energy takes place in the QD. Each level assumed to be four-fold degenerated. We suppose the existence of the strong electron–phonon interaction in the QD leading to the attraction of electrons that exceeds the Coulomb repulsion. This interaction results in breaking the degeneracy. The discrete levels can have lower energies than the Fermi energy of the electrode. The tunneling current through these levels will not be affected by the temperature. In the proposed mechanism of the cool electrons filtration, fitting parameters are absent and nevertheless a good agreement between the theory and experiment has been achieved.
Electro-hydrodynamic migration drives the concentration of DNA
Authors: Mandel Savannah
Published: July 2019

Transverse migration is used to concentrate and selectively trap DNA through microfluidic process and has advantages over traditional methods of extracting and purifying DNA.
Comparing the effectiveness and longevity of the urease inhibitor N-(2-nitrophenyl) phosphoric triamide (2-NPT) with N-(n-butyl) thiophosphoric triamide (nBTPT) in reducing ammonia emissions from cattle urine applied to dairy-grazed pasture soils
Authors: Adhikari Kamal P. , Saggar Surinder , Hanly James A. , Guinto Danilo F.
Published: July 2019

The objective of this laboratory incubation study was to assess the effectiveness and longevity of urease inhibitor N-(2-nitrophenyl) phosphoric triamide (2-NPT), along with the commonly used N-(n-butyl) thiophosphoric triamide (nBTPT), in reducing ammonia (NH3) emissions from cattle urine applied to pasture soils. It was hypothesised that 2-NPT would be effective as a longer-lasting inhibitor to reduce emissions after the deposition of urine during multiple grazing events. Two dairy-grazed pasture soils (Fluvisol, Rangitikei loamy sand (RLS) and Andosol, Egmont black loam (EBL)) with contrasting organic carbon levels and urease activity were used. The following treatments were applied to the soils at the start of the experiment: no inhibitor, nBTPT-low, 2-NPT-low, 2-NPT-medium and 2-NPT-high. Urine-N was applied to all the treatments at four stages: immediately before inhibitor application (Stage A), 29 days after inhibitor application (Stage B), 56 days after inhibitor application (Stage C) and 29 days and again 60 days after inhibitor application (Stage D); NH3 emissions were measured up to Day 31 after each urine application. The low, medium and high application rates of inhibitors were determined based on achieving 0.025%, 0.050% and 0.075% of quantity of urine-N applied in Stage A respectively. For the no inhibitor treatment, the proportion of total applied N in urine that was emitted as NH3 for the different stages ranged from 35.8% to 50.5% for RLS soil and from 14.2% to 26.7% for EBL soil. For Stage A, both inhibitors equally reduced NH3 emissions from applied urine in both soils (23.7–27.3% for the RLS and 20.6–27.2% for the EBL). For Stage B, significant reductions (4.2–13.4%) in NH3 emitted was observed only from RLS soil, with there being a significantly greater reduction from 2-NPT than from nBTPT, and 2-NPT continued to reduce NH3 emissions at Stage C (5.6–7.4%). There was no reduction in emissions during Stage D by either of the inhibitors. The results of this study suggest that 2-NPT can extend the longevity of urease inhibition and reduce NH3 emissions compared with the more commonly used inhibitor nBTPT in dairy-grazed pasture soils.
A stepwise mechanism for aqueous two-phase system formation in concentrated antibody solutions
Authors: Rogers Bradley A. , Rembert Kelvin B. , Poyton Matthew F. , Okur Halil I. , Kale Amanda R. , Yang Tinglu , Zhang Jifeng , Cremer Paul S.
Published: July 2019

Significance

Concentrated liquid formulations of therapeutic antibodies are susceptible to colloidal instability, including liquid–liquid phase separation (LLPS). Herein, we measure the kinetics of aqueous two-phase system (ATPS) formation, the macroscopic stage of LLPS, along a linear temperature gradient device. These studies indicate that ATPS formation proceeds by the growth of protein-rich droplets and their subsequent coalescence. Droplet growth accelerates as the solution is cooled because protein–protein interactions become increasingly free energetically favorable. At lower temperatures, however, ATPS formation is rate-limited by a small barrier to droplet coalescence. A gel can form at the coldest temperatures, which arrest phase separation. We propose a simple 2-step model that relates these results to a reaction coordinate diagram for ATPS formation.
Mechanical properties of upper torso rotation from the viewpoint of energetics during baseball pitching
Authors: Kimura Arata , Yoshioka Shinsuke , Omura Leon , Fukashiro Senshi
Published: July 2019

This study aims to examine if upper torso rotation is caused mainly by pelvis rotation during baseball pitching from the viewpoint of energetics. Twelve right‐handed males participated in this study. Five were and seven had been collegiate baseball pitchers, and all used an overarm style. They threw a baseball as fast and precisely as possible, and data from three strikes were used. A motion capture system consisting of 13 cameras and two force platforms was used to collect the data and calculate joint torques of the thoracic and the lumbar joint. The joint torque of the thoracic and the lumbar joint were calculated using a top‐down and a bottom‐up approach, respectively. Then, the mechanical energy generation and transfer by the torsional torques were quantified. The mechanical energy generation exerted by the torsional torques of the thoracic and lumbar joints were 0.03 ± 0.03 and 0.15 ± 0.04 J kg−1 m−1, respectively. The mechanical energy transfer exerted by the torsional torques of the thoracic and lumbar joints were 0.72 ± 0.19 and 0.88 ± 0.24 J kg−1 m−1, respectively. These results indicated that torsional torques transferred a substantial amount of mechanical energy from the pelvis to the upper torso. Furthermore, the findings indicate that the mechanical energy transfer exerted by the torsional torques was a major contributor to the upper torso rotation.
Extracellular vesicles mediate the horizontal transfer of an active LINE‐1 retrotransposon
Authors: Kawamura Yumi , Calle Anna Sanchez , Yamamoto Yusuke , Sato Taka‐Aki , Ochiya Takahiro
Published: July 2019

Long interspersed element‐1 (LINE‐1 or L1) retrotransposons replicate through a copy‐and‐paste mechanism using an RNA intermediate. However, little is known about the physical transmission of retrotransposon RNA between cells. To examine the horizontal transfer of an active human L1 retrotransposon mediated by extracellular vesicles (EVs), human cancer cells were transfected with an expression construct containing a retrotransposition‐competent human L1 tagged with a reporter gene. Using this model, active retrotransposition events were detected by screening for the expression of the reporter gene inserted into the host genome by retrotransposition. EVs including exosomes and microvesicles were isolated from cells by differential centrifugation. The enrichment of L1‐derived reporter RNA transcripts were detected in EVs isolated from cells expressing active L1 retrotransposition. The delivery of reporter RNA was confirmed in recipient cells, and reporter genes were detected in the genome of recipient cells. Additionally, employing qRT‐PCR, we found that host‐encoded factors are activated in response to increased exposure to L1‐derived RNA transcripts in recipient cells. Our results suggest that the horizontal transfer of retrotransposons can occur through the incorporation of RNA intermediates delivered via EVs and may have important implications for the intercellular regulation of gene expression and gene function.
A bipartite sorting signal ensures specificity of retromer complex in membrane protein recycling
Authors: Suzuki Sho W. , Chuang Ya-Shan , Li Ming , Seaman Matthew N.J. , Emr Scott D.
Published: July 2019

Retromer is an evolutionarily conserved protein complex, which sorts functionally diverse membrane proteins into recycling tubules/vesicles from the endosome. Many of the identified cargos possess a recycling signal sequence defined as ØX[L/M/V], where Ø is F/Y/W. However, this sequence is present in almost all proteins encoded in the genome. Also, several identified recycling sequences do not follow this rule. How then does retromer precisely select its cargos? Here, we reveal that an additional motif is also required for cargo retrieval. The two distinct motifs form a bipartite recycling signal recognized by the retromer subunits, Vps26 and Vps35. Strikingly, Vps26 utilizes different binding sites depending on the cargo, allowing retromer to recycle different membrane proteins. Thus, retromer interacts with cargos in a more complex manner than previously thought, which facilitates precise cargo recognition.
Resident memory CD8 T cells persist for years in human small intestine
Authors: Bartolomé-Casado Raquel , Landsverk Ole J.B. , Chauhan Sudhir Kumar , Richter Lisa , Phung Danh , Greiff Victor , Risnes Louise F. , Yao Ying , Neumann Ralf S. , Yaqub Sheraz , Øyen Ole , Horneland Rune , Aandahl Einar Martin , Paulsen Vemund , Sollid Ludvig M. , Qiao Shuo-Wang , Baekkevold Espen S. , Jahnsen Frode L.
Published: July 2019

Resident memory CD8 T (Trm) cells have been shown to provide effective protective responses in the small intestine (SI) in mice. A better understanding of the generation and persistence of SI CD8 Trm cells in humans may have implications for intestinal immune-mediated diseases and vaccine development. Analyzing normal and transplanted human SI, we demonstrated that the majority of SI CD8 T cells were bona fide CD8 Trm cells that survived for >1 yr in the graft. Intraepithelial and lamina propria CD8 Trm cells showed a high clonal overlap and a repertoire dominated by expanded clones, conserved both spatially in the intestine and over time. Functionally, lamina propria CD8 Trm cells were potent cytokine producers, exhibiting a polyfunctional (IFN-γ+ IL-2+ TNF-α+) profile, and efficiently expressed cytotoxic mediators after stimulation. These results suggest that SI CD8 Trm cells could be relevant targets for future oral vaccines and therapeutic strategies for gut disorders.
Impact of naturally forming human α/β-tryptase heterotetramers in the pathogenesis of hereditary α-tryptasemia
Authors: Le Quang T. , Lyons Jonathan J. , Naranjo Andrea N. , Olivera Ana , Lazarus Robert A. , Metcalfe Dean D. , Milner Joshua D. , Schwartz Lawrence B.
Published: July 2019

Both α-tryptase and β-tryptase are preferentially expressed by human mast cells, but the purpose of α-tryptase is enigmatic, because its tetramers lack protease activity, whereas β-tryptase tetramers are active proteases. The monogenic disorder called hereditary α-tryptasemia, due to increased α-tryptase gene copies and protein expression, presents with clinical features such as vibratory urticaria and dysautonomia. We show that heterotetramers composed of 2α- and 2β-tryptase protomers (α/β-tryptase) form naturally in individuals who express α-tryptase. α/β-Tryptase, but not homotetramer, activates protease-activated receptor-2 (PAR2), which is expressed on cell types such as smooth muscle, neurons, and endothelium. Also, only α/β-tryptase makes mast cells susceptible to vibration-triggered degranulation by cleaving the α subunit of the EGF-like module–containing mucin-like hormone receptor-like 2 (EMR2) mechanosensory receptor. Allosteric effects of α-tryptase protomers on neighboring β-tryptase protomers likely result in the novel substrate repertoire of α/β-tryptase tetramers that in turn cause some of the clinical features of hereditary α-tryptasemia and of other disorders involving mast cells.
Neutralizing antibodies against Mayaro virus require Fc effector functions for protective activity
Authors: Earnest James T. , Basore Katherine , Roy Vicky , Bailey Adam L. , Wang David , Alter Galit , Fremont Daved H. , Diamond Michael S.
Published: July 2019

Despite causing outbreaks of fever and arthritis in multiple countries, no countermeasures exist against Mayaro virus (MAYV), an emerging mosquito-transmitted alphavirus. We generated 18 neutralizing mAbs against MAYV, 11 of which had “elite” activity that inhibited infection with EC50 values of <10 ng/ml. Antibodies with the greatest inhibitory capacity in cell culture mapped to epitopes near the fusion peptide of E1 and in domain B of the E2 glycoproteins. Unexpectedly, many of the elite neutralizing mAbs failed to prevent MAYV infection and disease in vivo. Instead, the most protective mAbs bound viral antigen on the cell surface with high avidity and promoted specific Fc effector functions, including phagocytosis by neutrophils and monocytes. In subclass switching studies, murine IgG2a and humanized IgG1 mAb variants controlled infection better than murine IgG1 and humanized IgG1-N297Q variants. An optimally protective antibody response to MAYV and possibly other alphaviruses may require tandem virus neutralization by the Fab moiety and effector functions of the Fc region.
Roadmap on photonic, electronic and atomic collision physics: II. Electron and antimatter interactions
Authors: Schippers Stefan , Sokell Emma , Aumayr Friedrich , Sadeghpour Hossein , Ueda Kiyoshi , Bray Igor , Bartschat Klaus , Murray Andrew , Tennyson Jonathan , Dorn Alexander , Yamazaki Masakazu , Takahashi Masahiko , Mason Nigel , Novotný Oldřich , Wolf Andreas , Sanche Leon , Centurion Martin , Yamazaki Yasunori , Laricchia Gaetana , Surko Clifford M , Sullivan James , Gribakin Gleb , Savin Daniel Wolf , Ralchenko Yuri , Hoekstra Ronnie , O’Sullivan Gerry
Published: July 2019

We publish three Roadmaps on photonic, electronic and atomic collision physics in order to celebrate the 60th anniversary of the ICPEAC conference. In Roadmap II we focus on electron and antimatter interactions. Modern theoretical and experimental approaches provide detailed insight into the many body quantum dynamics of leptonic collisions with targets of varying complexity ranging from neutral and charged atoms to large biomolecules and clusters. These developments have been driven by technological progress and by the needs of adjacent areas of science such as astrophysics, plasma physics and radiation biophysics. This Roadmap aims at looking back along the road, explaining the evolution of the field, and looking forward, collecting contributions from eighteen leading groups from the field.
Ramsey-coherent population trapping Cs atomic clock based on lin∥lin optical pumping with dispersion detection*
Authors: Cheng Peng-Fei , Zhang Jian-Wei , Wang Li-Jun
Published: July 2019

A Cs vapor cell-based atomic clock that uses a lin∥lin pumping scheme with dispersion detection is reported. This atomic clock shows potential for high performance because of its high contrast pumping scheme, and for miniaturization because of its simple architecture. The experimental setup and optimal operating parameters for the clock are introduced. The current fractional frequency stability is measured to be

1.3
×

10

−
12

/

τ

up to 20 s and reaches

3.1
×

10

−
13

at 200 s. We have thoroughly investigated the related noise sources that affect clock frequency stability at the 1 s and 100 s levels. The investigation shows that the laser frequency noise limits the clock frequency stability significantly. The clock performance can be further improved by technically upgrading the laser frequency stabilization setup.
Possible nodeless s±-wave superconductivity in twisted bilayer graphene*
Authors: Liu Zhe , Li Yu , Yang Yi-Feng
Published: July 2019

The recent discovery of superconductivity in the twisted bilayer graphene has stimulated numerous theoretical proposals concerning its exact gap symmetry. Among them, the d+ id or p+ ip-wave was believed to be the most plausible solution. Here, considering that the superconductivity emerges near a correlated insulating state and may be induced by antiferromagnetic spin fluctuations, we apply the strong-coupling Eliashberg theory with both inter- and intraband quantum critical pairing interactions and discuss the possible gap symmetry in an effective low-energy four-orbital model. Our calculations reveal a nodeless s±-wave as the most probable candidate for the superconducting gap symmetry in the experimentally relevant parameter range. This solution is distinctly different from previous theoretical proposals. It highlights the multi-gap nature of the superconductivity and puts the twisted bilayer graphene in the same class as the iron-pnictide, electron-doped cuprate, and some heavy fermion superconductors.