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Short-range (SR) magnetic orders such as magnetic glass orders or fluctuations in a quantum system usually host exotic states or critical behaviors. As the long-range (LR) magnetic orders, SR magnetic orders can also break time-reversal symmetry and drive the non-zero Berry curvature leading to novel transport properties. In this work, we report that in EuZn$_2$As$_2$ compound, besides the LR A-type antiferromagnetic (AF) order, the SR magnetic order is observed in a wide temperature region. The magnetization measurements and electron spin resonance (ESR) measurements reveal the ferromagnetic (FM) correlations for this SR magnetic order which results in an obvious anomalous Hall effect above the AF transition. Moreover the ESR results reveal that this FM SR order coexists with LR AF order exhibiting anisotropic magnetic correlations below the AF transition. The interactions of LR and SR magnetism evolving with temperature and field can host non-zero spin charility and berry curvature leading the additional topological Hall contribution even in a centrosymmetric simple AF system. Our results indicate that EuZn$_2$As$_2$ is a fertile platform to investigate exotic magnetic and electronic states., 6 pages, 4 figures

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by recurrent arteriovenous thrombosis and/or morbid pregnancy. Valve involvement is the most common cardiac manifestation of APS, with lesions characterized by valve thickening and vegetations known as Libman-Sacks endocarditis (LSE). This report discussed a rare case of a 26-year-old young woman diagnosed with primary APS with multiple cerebral infarctions and right middle cerebral artery occlusion that occured 3 years ago. During the investigation, transthoracic echocardiography (TTE) revealed vegetations on both leaflets of the mitral valve with mild to moderate mitral regurgitation. One year following corticosteroid and anticoagulant treatment, mitral valve fibrosis and moderate to severe regurgitation were noted, after which mitral mechanical valve replacement was finally performed. Accordingly, this report suggests that LSE occurrence should be alerted during the examination of APS patients especially in those with cerebrovascular disease. Furthermore, establishing an early diagnosis and conducting close follow-ups are necessary for its timely intervention and treatment.

Additional file 1: Supplement Fig. 1. Calculations of sample size and model power.

We demonstrate an unconventional near-infrared photodetector fabricated from a ZnO chip with a metallic subwavelength grating structure as a contact and optical window, which harvests hot electrons generated by plasmonic resonances introduced by incident light. The grating structure has a strong selection of the polarization of incident light, meaning that the detector is naturally polarization-sensitive. In our device, the polarization extinction ratio is as high as 64:1, much higher than that relying on crystal orientations. Since the photoresponse is introduced by plasmonic resonance, a narrow photoresponse spectrum with a linewidth of 32.1 nm at 1.201 μm is obtained. By simply changing the grating period, the spectral position can be tailored freely within the near-infrared region, i.e., wavelength-selective. Such a spectral response is not likely to be realized with conventional semiconductor photodetectors, which depend on the band edge absorption. We propose a modified Fowler's model, which well explains the line shape of photoresponse spectra of such devices.

The epitaxial growth of technically-important $\beta$-Ga$_2$O$_3$ semiconductor thin films have not been realized on flexible substrates due to limitations by the high-temperature crystallization conditions and the lattice-matching requirements. In this report, for the first time single crystal $\beta$-Ga$_2$O$_3$(-201) thin films is epitaxially grown on the flexible CeO2 (001)-buffered hastelloy tape. The results indicate that CeO$_2$ (001) has a small bi-axial lattice mismatch with $\beta$-Ga$_2$O$_3$ (-201), thus inducing a simultaneous double-domain epitaxial growth. Flexible photodetectors are fabricated based on the epitaxial $\beta$-Ga$_2$O$_3$ coated tapes. Measurements show that the obtained photodetectors have a responsivity of 40 mA/W, with an on/off ratio reaching 1000 under 250 nm incident light and 5 V bias voltage. Such photoelectrical performance is already within the mainstream level of the $\beta$-Ga$_2$O$_3$ based photodetectors by using the conventional rigid single crystal substrates; and more importantly remained robust against more than 1000 cycles of bending tests. In addition, the epitaxy technique described in the report also paves the way for the fabrication of a wide range of flexible epitaxial film devices that utilize the materials with lattice parameters similar to $\beta$-Ga$_2$O$_3$, including GaN, AlN and SiC., Comment: 25 pages, 10 figures

The epitaxial growth of technically-important $��$-Ga$_2$O$_3$ semiconductor thin films have not been realized on flexible substrates due to limitations by the high-temperature crystallization conditions and the lattice-matching requirements. In this report, for the first time single crystal $��$-Ga$_2$O$_3$(-201) thin films is epitaxially grown on the flexible CeO2 (001)-buffered hastelloy tape. The results indicate that CeO$_2$ (001) has a small bi-axial lattice mismatch with $��$-Ga$_2$O$_3$ (-201), thus inducing a simultaneous double-domain epitaxial growth. Flexible photodetectors are fabricated based on the epitaxial $��$-Ga$_2$O$_3$ coated tapes. Measurements show that the obtained photodetectors have a responsivity of 40 mA/W, with an on/off ratio reaching 1000 under 250 nm incident light and 5 V bias voltage. Such photoelectrical performance is already within the mainstream level of the $��$-Ga$_2$O$_3$ based photodetectors by using the conventional rigid single crystal substrates; and more importantly remained robust against more than 1000 cycles of bending tests. In addition, the epitaxy technique described in the report also paves the way for the fabrication of a wide range of flexible epitaxial film devices that utilize the materials with lattice parameters similar to $��$-Ga$_2$O$_3$, including GaN, AlN and SiC., 25 pages, 10 figures

By means of all optical characterizations, carrier dynamics of GaZn–VZn defect complex in Ga doped ZnO film has been systematically studied. It is observed that the defect complex exhibits a red emission centered at 650 nm, different from that of a reference sample containing VO only. From our observations using time-resolved photoluminescence and multiple-wavelength excitation photoluminescence measurements, the energy level of GaZn–VZn is determined to be a two-level system, which is fundamentally different from the reference sample with only a deep level in term of carrier dynamics. This work reveals that GaZn–VZn distinguished from the widely observed VO is a potential candidate for new single photon emitters.

A single-phase wurtzite MgZnO film with an optical band gap of 294.5 nm was synthesized on ZnO substrate by molecular beam epitaxy, and a photodetector was fabricated working in the ultraviolet-B spectrum region. Wurtzite BeO was adopted to restrain the substrate response as an insulating layer and provide an excellent epitaxial template for high-Mg-content MgZnO growth. In situ reflection high-energy electron diffraction observations, ex situ X-ray diffraction and reflectance spectrum indicate the achievement of high-quality single-phase wurtzite MgZnO with smooth surface and deep ultraviolet band gap. The BeO layer efficiently suppresses the photoresponse from the substrate, as the photo-detector demonstrates a sharp cutoff at 290 nm, consistent with the optical band gap. (C) 2013 Elsevier B.V. All rights reserved.

A potentially fatal microsporidial infection targeting the skeletal muscles of the tiger barb Puntius tetrazona was described. Ultrastructural and molecular analyses of infected tissues confirmed that the causative parasite was Pleistophora hyphessobryconis. Compared to P. hyphessobryconis observed in other hosts, those infecting tiger barb demonstrated differences in ultrastructure that may be related to host adaptation. Phylogenetic analysis revealed that classifications based on different methods of analysis (molecular, morphologic, or developmental) do not always coincide, and suggesting that the genetic relationships between Pleistophora and Ovipleistophora may need to be redefined. Transparent mutants of tiger barb can be artificially infected by P. hyphessobryconis, and the dynamic process and spatial distribution of P. hyphessobryconis infection can be observed in real time. These transparent fish mutants are a valuable model to study microsporidial infection in vivo.

Single-phase rock-salt Mg0.3Zn0.7O film was fabricated on MgO (100) substrate by radio-frequency plasma assisted molecular beam epitaxy. A smooth surface was observed by in-situ reflection high-energy electron diffraction and ex-situ atomic force microscopy. X-ray diffraction characterization demonstrated a high-quality single-phase structure with highly (200) orientation and cube-on-cube epitaxial relationship. Zn fraction in the single-phase rock-salt Mg0.3Zn0.7O film was determined by Rutherford backscattering spectrometry. Optical property of the film was investigated by reflectance spectroscopy, which indicated a solar-blind band gap of 255.5 nm. The reason why Zn solubility limit is greatly enhanced in non-polar (100) film compared with (111) polar epilayer is tentatively discussed in this work, suggesting MgO (100) is more suitable for the synthesis of single-phase rock-salt MgZnO with high Zn content towards solar-blind opto-device applications.

Broadband antireflection of silicon has been realized by combining black silicon, surface passivation and surface plasmons. Black silicon, fabricated by Ag assisted chemical etching, was employed here to reduce the reflection of incident light with wavelengths below 1100 nm. Due to the increased bandgap caused by the quantum confinement effect and enhanced backward-scattering in our black silicon, light trapping was diminished at the wavelengths above 1100 nm. Ag nanoparticles were deposited on black silicon to obtain the lowest reflectivity at the wavelengths above 1100 nm. Compared with traditionally textured multicrystalline silicon, the average reflectivity of passivated black multicrystalline silicon patterned with 5 nm mass thickness of Ag was decreased to 5.7% in the wavelength range from 300 nm to 1100 nm and was reduced by 20.2% in the wavelength range from 1100 nm to 1400 nm. The surface plasmon effect of the Ag nanoparticles on the black silicon was also demonstrated by surface enhanced Raman scattering, which was observed in the Ag nanoparticle patterned black silicon after being immersed in rhodamine 6g.

A unique ultraviolet photodetector based on a metal-semiconductor-metal structure was fabricated from a wurtzite MgxZn1−xO film with gradually changing Mg content, homoepitaxially grown on a BeO-buffered ZnO substrate. The BeO layer filtered out the substrate photoresponse. The cutoff wavelength of the photodetector under zero bias was 266 nm with a UV/visible light rejection ratio of greater than 2 orders of magnitude in the deep UV region. Applying a bias, the cutoff wavelength exhibited a prominent continuous redshift from 266 (0 V) to 315 nm (3 V), indicating the capability for multi-band UV detection on a monolithic chip. The bias-controlled wavelength-selective UV photoresponse mechanism occurred in the optically active area in a compositionally distributed MgxZn1−xO alloy that was achieved by molecular epitaxial growth.

We have constructed a dual-band ultraviolet photodetector by growing high quality MgxZn1−xO layers on Si substrate with molecular beam epitaxy. The device performance was studied by current-voltage, capacitance-voltage, spectra photoresponse, and time-resolved photoresponse characterizations. It demonstrates a high UV/visible light rejection ratio of more than 2 orders of magnitude and a fast response speed of less than 100 ms. The cutoff wavelength can be at solar-blind (280 nm)/visible-blind (301 nm) region by applying 1 V forward/2 V reverse bias. The working principle of the dual-band photodetector was finally investigated by interpretation of the specific carrier transport behavior with the energy band diagram.

Hybrid snakehead(Channa maculata♀ × C.argus♂) is one of the most popular species cultured in the areas of eastern and southern China.With high density culture and rapid expanding production,problems of its diseases become more and more serious.A disease with white spots in internal organs of hybrid snakehead broke out in Fushan and Guangzhou in Guangdong Province in 2011.Bacteria pathogens were isolated from diseased hybrid snakehead cultured in pond.Two bacteria strains with strong virulence were chosen for identifications.The morphological,biochemical and physiological characteristics of the two isolates were studied by using conventional method,ATB Expression System(ID32 STREP)and other assays,and the characteristics of the isolated strains were in accordance with those of Aeromonas schubertii.Molecular analyses of 16S rRNA and gyrB genes were used for further identification.BLAST showed that 16S rRNA and gyrB genes of two strains possessed high similarities with their counterparts registered in GenBank and with each other.The virulent tests were carried out by using the pure culture of the isolated strains artificially infected hybrid snakehead,and the result indicated that the high concentration of bacteria(≥1 × 10 7 CFU/mL) caused acute death,and infected diseased fish displayed symptom of sarcoidosis after three days,while the control group showed no signs in 7d post-challenge.The morphological and biochemical characteristics of the re-isolated bacteria from the artificially infected diseased fish were the same as those of the original infected bacteria.Antibiotic sensitivity assays showed that among 16 antibiotics tested 14 were sensitive,and 2 were resistant.

A comparative study of n-MgZnO/p-Si UV-B photodetector performance was carried out with different device structures. The experimental results demonstrate superior photoresponse characteristics of the p-n heterojunction detector against the Schottky type metal-semiconductor-metal counterpart, including a sharper cutoff wavelength at 300 nm, a larger peak photoresponsivity of 1 A/W, and a faster response speed. The role of built-in field and low interface scattering in p-n heterojunction is explored, and the energy band diagram of n-MgZnO/p-Si is employed to interpret the efficient suppression of visible light photoresponse from Si substrate, revealing the applicability of this heterostructure in fabrication of deep ultraviolet detectors.

High-quality wurtzite MgZnO film was deposited on Si(111) substrate via a delicate interface engineering using BeO, by which solar-blind ultraviolet photodetectors were fabricated on the n-MgZnO(0001)/p-Si(111) heterojunction. A thin Be layer was deposited on clean Si surface with subsequent in situ oxidation processes, which provides an excellent template for high-Mg-content MgZnO growth. The interface controlling significantly improves the device performance, as the photodetector demonstrates a sharp cutoff wavelength at 280 nm, consistent with the optical band gap of the epilayer. Our experimental results promise potential applications of this technique in integration of solar-blind ultraviolet optoelectronic device with Si microelectronic technologies.

Stokes shifts and near-band emission in high-Mg-content single-phase wurtzite Mg x Zn1−x O (0.27 ⩽ x ⩽ 0.55) epilayers were investigated by photoluminescence (PL) and photoluminescence excitation combining laser and synchrotron excitation experiments. The observed Stokes shifts (e.g. 365 meV for the sample containing 55% Mg) as well as the ‘S-shaped’ temperature dependence of the maximum PL emissions were explained in terms of Mg compositional fluctuations in our sample resulting in exciton localization in potential traps and, consequently, suppression of non-radiative recombination making high-Mg-content MgZnO a good candidate for optical applications.