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Background: Several epidemiological articles have reported the correlations between anti-osteoporosis medication and the risks of fractures in male and female subjects, but the specific efficacy of anti-osteoporosis medication for male subjects remains largely unexplored.Objective: The aim of this study was to evaluate the correlation between anti-osteoporosis medication and the risk of fracture in relation to low bone mass [including outcomes of osteoporosis, fracture, and bone mineral density (BMD) loss] in male subjects analyzed in studies within the updated literature.Methods: Randomized controlled trials (RCTs) that analyzed the effectiveness of a treating prescription for male subjects with osteoporosis (or low BMD) and that focused on the outcomes of fracture were included. Relevant studies from Embase, Web of Science, PubMed, and Chinese database of CNKI were retrieved from inception to January 30th, 2019. Two staff members carried out the eligibility assessment and data extraction. The discrepancies were settled by consultation with another researcher. We calculated the pooled relative risks (RRs) based on 95% confidence intervals (CIs).Results: Twenty-seven documents (28 studies) with 5,678 subjects were identified. For the category of bisphosphonates, significant results were observed in pooled analyses for decreased risk of the vertebral fracture domain (RR, 0.44 [95% CI, 0.31–0.62]), nonvertebral fracture domain (RR, 0.63 [95% CI, 0.46–0.87]), and clinical fracture domain (RR, 0.59 [95% CI, 0.48–0.72]) compared with those of controls. Participants with bisphosphonates had a 56% (95% CI = 38–69%) lower risk of vertebral fractures, 37% (95% CI = 13–54%) lower risk of nonvertebral fractures, and 41% (95% CI = 28–52%) lower risk of clinical fractures. Furthermore, meta-analyses also demonstrated a decreased risk of the vertebral fracture domain via treatment with risedronate (RR, 0.45 [95% CI, 0.28–0.72]) and alendronate (RR, 0.41 [95% CI, 0.23–0.74]), but not with calcitriol, calcitonin, denosumab, ibandronate, monofluorophosphate, strontium ranelate, teriparatide, or zoledronic acid, compared with that of controls.Conclusions: This systematic review confirms that bisphosphonates were connected with a decreased risk of vertebral fractures, nonvertebral fractures, and clinical fractures for male subjects with osteoporosis. Future research is needed to further elucidate the role of nonbisphosphonates in treating fractures of osteoporosis subjects.

We report our design of a tunable one-way cross-waveguide splitter, resulting from the broken time-reversal symmetry, based on the edge modes of gyromagnetic photonic crystal. Mode control is accomplished by altering the radius or refractive index of a single central electro-optical rod. The on-off switch of the channels can be manipulated by external electric or magnetic field. Coupled-mode theory between defect modes and waveguide modes was used to characterize the transmission efficiency of the channels. [ABSTRACT FROM AUTHOR]

In this letter, self-collimated beam of surface acoustic waves (SAWs) based on phononic crystals (PnCs), made of cone-shaped micropillars attached on a half-space, are numerically demonstrated and utilized for device applications. The self-collimated SAW beam can be split by a geometric line defect in PnCs. Of special interest is that the energy ratio of self-collimated beams can be adjusted by varying the radius of the micropillars of the defect. As functional displays with scalability and integrability, a one-to-three beam splitter and a Mach–Zehnder interferometer of SAWs are designed by utilizing this mechanism, providing prospects for on-chip SAW sensing or signal filtering. [ABSTRACT FROM AUTHOR]

Single-phase, insulating Bi1-xLaxFeO3 (BLFOx, x=0.05, 0.10, 0.15, 0.20, 0.30, and 0.40) ceramics were prepared. An obvious phase transition from rhombohedral to orthorhombic phase was observed near x=0.30. It is found that the phase transition destructs the spin cycloid of BiFeO3 (BFO), and therefore, releases the locked magnetization and enhances magnetoelectric interaction. As a result, improved multiferroic properties of the BLFO0.30 ceramics with remnant polarization and magnetization (2Pr and 2Mr) of 22.4 μC/cm2 and 0.041 emu/g, respectively, were established. [ABSTRACT FROM AUTHOR]

(1-x)BaTiO3-xNaNbO3 (x=0.025, 0.050, and 0.075) thin films were prepared on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. The structures, ferroelectric and dielectric properties were found to be strongly dependent on the composition wherein the ferroelectric polarization, tunability and temperature coefficient of capacitor (TCC) decrease with increasing x. At an applied field of 390 kV/cm, the room-temperature tunability are 67%, 38%, and 7% for the films with x=0.025, 0.050, and 0.075, respectively. Especially, the tunability reaches 78% with a field of 610 kV/cm for the films with x=0.025. The measured negative TCC values of these films are 1.7×10-3/°C, 1.0×10-3/°C, and 8.9×10-4/°C, respectively. [ABSTRACT FROM AUTHOR]

To realize the hole-mediated ferromagnetism, manganese and nitrogen-codoped ZnO (Zn1-xMnxO:N) films were prepared on sapphire (0001) by reactive radio-frequency (rf) magnetron sputtering from Zn0.97Mn0.03O ceramic targets using N2 gas. X-ray photon spectra reveal that the doped Mn ions are mainly in divalent states and the coexistence of O–Zn and N–Zn bonds in the films. According to the absorption spectra, the band gap of Zn0.97Mn0.03O:N films is about 3.15 eV, which is slightly lower than that of ZnO films (3.20 eV). Compared with Zn0.97Mn0.03O films, ferromagnetic behavior of Zn0.97Mn0.03O:N films were significantly changed with a coercivity of about 70 Oe, a saturation magnetization of 0.92 μB/Mn2+ and a remanance over 0.15 μB/Mn2+ at 300 K, while at 10 K, they increased to be about 110 Oe, 1.05 μB/Mn2+ and 0.23 μB/Mn2+, respectively. However, rapid thermal annealing treatment in pure oxygen results in a significant decrease on the magnetic properties of the films. [ABSTRACT FROM AUTHOR]

This study examined the role of early visual experience and age in the recognition of emotional prosody among students with visual impairments in China. A total of 75 primary and junior high school students participated in the study. The ability of participants to recognize the prosody of four basic emotions (sadness, anger, happiness, and neutrality) was explored. The findings were as follows. (1) Early visual experience had a significant effect on the recognition of emotional prosody. The accuracy rate of students with congenital blindness was lower than that of students with adventitious blindness, and the performance of students with congenital blindness was lower than that of sighted students. The students with congenital blindness exhibited the slowest recognition speeds. (2) Age had a significant effect on the emotional prosody recognition accuracy of the sighted students, but it had no effect on the students with blindness. [ABSTRACT FROM AUTHOR]

An iron foam/silica aerogel composite (IFSA) with bimodal structure was designed and fabricated to solve the contradictions between acoustic damping and mechanical strength of a material. IFSA exhibits excellent broadband sound absorption performance with average absorption of ∼57% (500–6400 Hz) and maximum absorption coefficient of 0.995 at 4336 Hz, and high specific stiffness (1.6 × 105 m2 s−2). The dissipation mechanism of sound energy in IFSA is well predicted by a designed bimodal model. Such fascinating artificial composite not only provides new insights for developing structural materials with high noise reduction and strength, but also has great potential applications for various fields. [ABSTRACT FROM AUTHOR]

In this letter, we present an elastic slow-wave waveguide, which utilizes and transports valley pseudospins in a two-dimensional plate phononic crystal (PnC). Both straight and bent waveguides are made for demonstrating the backscattering suppression of elastic edge-state transport due to valley-dependent pseudospins. By band structure engineering, elastic waves in a plate waveguide can be transported at ultralow velocities with considerable robustness, which is very promising for the generation of new solid-state phononic circuits with great versatility. [ABSTRACT FROM AUTHOR]

Dirac semimetals are materials in which the conduction and the valence bands have robust crossing points protected by topology or symmetry. Recently, a new type of Dirac semimetals, so called the Dirac line-node semimetals (DLNSs), have attracted a lot of attention, as they host robust Dirac points along the one-dimensional (1D) lines in the Brillouin zone (BZ). In this work, using angle-resolved photoemission spectroscopy (ARPES) and first-principles calculations, we systematically investigated the electronic structures of non-symmorphic ZrSiS crystal where we clearly distinguished the surface states from the bulk states. The photon-energy-dependent measurements further prove the existence of Dirac line node along the X–R direction. Remarkably, by in situ surface potassium doping, we clearly observed the different evolutions of the bulk and surface electronic states while proving the robustness of the Dirac line node. Our studies not only reveal the complete electronic structures of ZrSiS, but also demonstrate the method manipulating the electronic structure of the compound. [ABSTRACT FROM AUTHOR]

In the title compound, C18H12O2, the non-H atoms are nearly coplanar, the maximum atomic deviation being 0.113 (2) Å. π–π stacking is observed in the crystal structure, the shortest centroid–centroid distance being 3.5983 (19) Å. The molecular packing is further stabilized by weak C—H...O hydrogen bonds, forming an infinite chain along [100] and generating a C(6) motif.

The title compound, C14H16, was prepared through [2 + 2] cycloaddition of norbornadiene. There are two independent molecules in the asymmetric unit: each is centrosymmetric with the centroid of the four-membered ring located about an inversion center. Each molecule possesses an exo–trans–exo conformation.

In the title compound, C10H5N3O2, the benzylidenemalononitrile unit is nearly planar, with a maximum deviation of 0.129 (2) Å for a terminal N atom; the nitro group is approximately coplanar with the benzene ring [dihedral angle = 8.8 (3)°]. An intramolecular C—H...N hydrogen bond stabilizes the molecular conformation.

The title compound, C18H19N3O, displays an E conformation with respect to the C=N double bond. The dihedral angle between the mean planes of the two benzene rings is 24.49 (3)°. An intramolecular O—H...N hydrogen bond generates an S(6) ring. In the crystal, molecules are linked by nonclassical intermolecular C—H...O hydrogen bonds to form an infinite one-dimensional chain along [010], generating a C(8) motif.

In the title compound, C17H14N2O2, the asymmetric unit comprises two molecules that are comformationally similar [the dihedral angles between the phenyl rings in each are 46.35 (2) and 48.04 (3)°], with the conformation stabilized by intramolecular O—H...N hydrogen bonds, which generate S(7) rings. In the crystal, inversion-related molecules are linked by pairs of weak C—H...O hydrogen bonds, forming dimers with an R22(16) graph-set motif. Weak inter-ring π–π stacking is observed in the structure, the shortest centroid-to-centroid distance being 3.7480 (13) Å.

In the title compound, C13H11N3O2, an intramolecular O—H...N hydrogen bond generates an S(7) ring. The dihedral angle between the mean plane of the benzene ring and the imidazolidinone ring is 3.05 (2)°. In the crystal, inversion-related molecules are linked by dual C—H...Ocarbonyl hydrogen bonds to form a dimer with an R22(14) graph-set motif. A C—H...Ohydroxy interaction links pairs of molecules into another type of cyclic dimer with an R22(18) motif. The molecules are further linked by C—H...N interactions to form layers parallel to (001). Offset π–π stacking [3.3877 (8) Å] is observed in the crystal structure, with an interplanar spacing between the planes of neighboring benzene rings of 3.444 (1) Å.

The title compound, C17H12N2, comprises a norbornane unit having a dicyanonaphthalene ring fused on one side. Both cyano groups are twisted slightly out of the plane of the naphthalene ring system [C—C—C—C torsion angle = 1.9 (2)°]. In the crystal, inversion-related molecules are linked by pairs of weak C—H...N hydrogen bonds, forming dimers.

The molecule of the title compound, C14H9NO2S, is nearly planar, the maximum atomic deviation being 0.081 (2) Å. An intramolecular O—H...N bond generates an S(6) ring motif. In the crystal, inversion-related molecules linked by a pair of weak C—H...O hydrogen bonds form a supramolecular dimer. π–π stacking is observed between the thiazole and benzene rings of adjacent molecules, the centroid–centroid distance being 3.7679 (9) Å.

The polaritons in a two-dimensional artificial ionic-type crystal have been proposed and experimentally demonstrated from the two-dimensional periodically poled LiTaO3. In this artificially micro-structured materials, the anisotropic piezoelectric coefficients and the two-dimensional symmetric result in strong and complex couplings of the incident electromagnetic waves and the two-dimensional superlattice vibrations. We studied the dielectric anomalies, the coupling and transforming between two ordinary polariton modes etc., which reveal that, by engineering the ferroelectric domain's distribution, the artificial ionic-type crystal may establish a new member of meta-materials, and will facilitate access to the device applications such as multi-directional and frequency transducers. [ABSTRACT FROM AUTHOR]

We theoretically reveal that a two-dimensional magneto-optical photonic crystal shows two pairs of one-way edge Dirac cones, whereby only clockwise and anticlockwise circle wave scattering (facing the direction of external applied magnetic field) are allowed in the second and third band-gaps, respectively. These two different chiral pathways originate from the different exchange of Chern numbers, which are attributed to the broken time-reversal symmetry. Moreover, below and above the edge Dirac point, the edge modes show the left-handed (counter propagation of group velocity and phase velocity) and right-handed characters, respectively. [ABSTRACT FROM AUTHOR]

(Mn, Co)-codoped ZnO films have been synthesized on c-sapphire (0001) by a radio-frequency magnetron sputtering system in which two targets were sputtered together. X-ray-diffraction measurements indicate that the films are highly c-axis oriented. X-ray photon spectra show that the doped Mn and Co ions in (Mn, Co) ZnO films are both in the divalent states. The films show ferromagnetic behavior with a coercivity of about 90 Oe and a saturation moment of 0.11μB/(0.3Mn2++0.7Co2+) at 300 K. In the lower temperatures between 5 and 20 K, a relatively large positive magnetoresistance over 10% was observed for (Mn0.03, Co0.07)Zn0.90O film. The number of carrier concentration is experimentally established to be 1.5613×1018 cm-3 and the mobility to be 2.815 cm2 V-1 s-1 for (Mn0.03, Co0.07)Zn0.90O film by Hall measurements at 300 K. The origins of the room-temperature magnetism and the large positive magnetoresistance are also discussed. [ABSTRACT FROM AUTHOR]

We investigate both experimentally and numerically a complex structure, where ‘face-to-face’ Helmholtz resonance cavities (HRCs) are introduced to construct a one-dimensional acoustic grating. In this system, pairs of HRCs can intensely couple with each other in two forms: a bonding state and an anti-bonding state, analogous to the character of hydrogen molecule with two atoms due to the interference of wave functions of sound among the acoustic local-resonating structures. The bonding state is a ‘bright’ state that interferes with the Fabry–Pèrot resonance mode, thereby causing this state to break up into two modes as the splitting of the extraordinary acoustic transmission peak. On the contrary, the anti-bonding state is a ‘dark’ state in which the resonance mode remains entirely localized within the HRCs, and has no contribution to the acoustic transmission. [ABSTRACT FROM AUTHOR]

Abstract: On the basis of the co-integration method and the VAR model, this paper analyzed the interactive relations among Chinese domestic trade, foreign trade and economic growth by impulse response faction, finding that at the 5% significant level, the economic growth relates to the domestic trade and the domestic trade to the foreign trade both in the manner of the bidirectional Granger causality; however, economic growth Granger causes foreign trade but foreign trade does not Granger cause economic growth. In the long run, economic growth can not only have self-promotion, but also have remarkable positive effects on both domestic trade and foreign trade; the domestic trade lacks organizing faculty and has little effect on economic growth; the foreign trade itself has big fluctuations but its effects on economic growth are significant though unstable; the two kinds of trade are in the relation of mutual substitution. [ABSTRACT FROM AUTHOR]

Layered transition-metal dichalcogenides have been recently attracted a lot of attention because of their unique physical properties, such as extremely large and anisotropic magnetoresistance (MR) in WTe2. In this work, we observed the abnormally anisotropic MR on Td-MoTe2 crystal that is strongly dependent on the temperature, as well as the orientations of both magnetic field B and electric field E with respect to crystallographic axes of Td-MoTe2. When E//a-axis and B//c-axis, MR is parabolically dependent on B and is as high as 520% under 9 T and 2K conditions; the MR is quasi-linearly dependent on B when E//a-axis and B//b-axis (E//b-axis and B//c-axis), and the corresponding MR is only 130% (220%); MR is initially parabolically dependent on B, then linearly on B, and finally shows a saturate trend under E//B//a-axis (or E//B//b-axis) conditions, and the MR is about 16% (30%). These anisotropic MR behaviors can be qualitatively explained by the features of the Fermi surface of Td-MoTe2. This work may demonstrate the rich anisotropic physical behavior in layered transition-metal dichalcognides. [ABSTRACT FROM AUTHOR]

Recently, transition metal dichalcogenide (TMD) materials have shown promise in electronics and optoelectronics applications. Most of their properties are closely related to their abundant structural phases and phase transitions. For more practical applications in the future, it is necessary to tune the phase transitions in this material system. Here, we demonstrate the modulation of phase transitions in miscible WxMo1-xTe2 samples by appropriate alloying. The temperature dependent thermal conductivity along the c-axis, which strongly relates to the phase structures and the defect level, has been measured using the time-domain thermoreflectance method. In addition, a tunable hysteretic effect, induced by phase transitions, is observed in both thermal and electrical transport properties and confirmed by the consistent hysteresis in the Raman spectroscopic study. This hysteretic effect can be applied to realize phase-change storage devices. Furthermore, we provide a phase diagram to illustrate the composition dependent phase transition in WxMo1-xTe2. This work demonstrates an approach to modulate phase transition and thermal hysteresis in such a TMD material system by alloying engineering. [ABSTRACT FROM AUTHOR]

The domain evolution of 0.9625Bi0.5Na0.5TiO3-0.0375BiZn0.5Ti0.5O3 ceramic is studied by piezoelectric force microscopy. Nanodomains are the most common in the as-prepared ceramic, and they can transform to monodomain in a micrometer-scale grain under a large external electric field, which corresponds to a maximum piezoelectric d 33 coefficient. After the field is removed, the mondomain commonly decomposes gradually, and occasionally it transforms to periodic stripe-like domains. This experiment exhibits the domain evolution during poling and depoling processes of a normal ferroelectric ceramic, which is different from ergodic relaxors. [ABSTRACT FROM AUTHOR]

Optical communications and computing require on-chip nonreciprocat light propagation to isolate and stabilize different chip-scale optical components. We have designed and fabricated a metallic-silicon waveguide system in which the optical potential is modulated along the length of the waveguide such that nonreciprocal light propagation is obtained on a silicon photonic chip. Nonreciprocal light transport and one-way photonic mode conversion are demonstrated at the wavelength of 1.55 micrometers in both simulations and experiments. Our system is compatible with conventional complementary metal-oxide-semiconductor processing, providing a way to chip-scale optical isolators for optical communications and computing. [ABSTRACT FROM AUTHOR]

Despite a long history of studies, acoustic waves are generally regarded as spinless scalar waves, until recent research revealed their rich structures. Here, we report the experimental observation of skyrmion configurations in acoustic waves. We find that surface acoustic waves trapped by a designed hexagonal acoustic metasurface give rise to skyrmion lattice patterns in the dynamic acoustic velocity fields (i.e., the oscillating acoustic air flows). Using an acoustic velocity sensing technique, we directly visualize a Néel-type skyrmion configuration of the acoustic velocity fields. We further demonstrate, respectively, the controllability and robustness of the acoustic skyrmion lattices by tuning the phase differences between the acoustic sources and by introducing local perturbations in our setup. Our study unveils a fundamental acoustic phenomenon that may enable unprecedented manipulation of acoustic waves and may inspire future technologies including advanced acoustic tweezers for the control of small particles. [ABSTRACT FROM AUTHOR]

Topological insulators (TIs), featured by a symmetry-protected gapless surface Dirac cone(s) in their complete energy band gaps, have been extended from condensed-matter physics to classical bosonic systems in the last decade. However, acoustic TIs in three dimensions remain elusive because of a lack of a spin or polarization degree of freedom for longitudinal airborne sound. Here, we experimentally demonstrate a feasible way to hybridize an acoustic TI in three dimensions based on band inversion through a three-dimensional (3D) hybrid Dirac point (HDP). Such a 3D HDP, with linear dispersion in the layer plane while quadratic out of the layer, is distinct from a general point with linear dispersion in all directions. Interestingly, a single nearly gapless conical-like dispersion for acoustic surface states can be achieved at both zigzag and armchair interfaces, supporting robust sound transport. Our findings can serve as a tabletop platform for exploring unique acoustic applications based on the two-dimensional topological interfaces. [ABSTRACT FROM AUTHOR]

The studies of topological phases of matter have been developed from condensed matter physics to photonic systems, resulting in fascinating designs of robust photonic devices. Recently, higher-order topological insulators have been investigated as a novel topological phase of matter beyond the conventional bulk-boundary correspondence. Previous studies of higher-order topological insulators have been mainly focused on the topological multipole systems with negative coupling between lattice sites. Here we experimentally demonstrate that second-order topological insulating phases without negative coupling can be realized in two-dimensional dielectric photonic crystals. We visualize both one-dimensional topological edge states and zero-dimensional topological corner states by using the near-field scanning technique. Our findings open new research frontiers for photonic topological phases and provide a new mechanism for light manipulating in a hierarchical way. [ABSTRACT FROM AUTHOR]

The asymmetric electron dispersion in type-II Weyl semimetal theoretically hosts anisotropic transport properties. Here, we observe the significant anisotropic Adler-Bell-Jackiw (ABJ) anomaly in the Fermi-level delicately adjusted WTe1.98 crystals. Quantitatively, CW, a coefficient representing the intensity of the ABJ anomaly along the a and b axis of WTe1.98 are 0.030 and 0.051 T-2 at 2 K, respectively. We found that the temperature-sensitive ABJ anomaly is attributed to a topological phase transition from a type-II Weyl semimetal to a trivial semimetal, which is verified by a first-principles calculation using experimentally determined lattice parameters at different temperatures. Theoretical electrical transport study reveals that the observation of an anisotropic ABJ along both the a and b axes in WTe1.98 is attributed to electrical transport in the quasiclassical regime. Our work may suggest that electron-doped WTe2 is an ideal playground to explore the novel properties in type-II Weyl semimetals. [ABSTRACT FROM AUTHOR]

We report an atomic-scale characterization of ZrTe5 by using scanning tunneling microscopy. We observe a bulk band gap of ~80 meV with topological edge states at the step edge and, thus, demonstrate that ZrTe5 is a two-dimensional topological insulator. We also find that an applied magnetic field induces an energetic splitting of the topological edge states, which can be attributed to a strong link between the topological edge states and bulk topology. The relatively large band gap makes ZrTe5 a potential candidate for future fundamental studies and device applications. [ABSTRACT FROM AUTHOR]