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The fragmentation dynamics of two isomers of C

Biological probes with integrated photoluminescence and magnetism characteristics play a critical role in modern clinical diagnosis and surgical protocols combining fluorescence optical imaging (FOI) with magnetic resonance imaging (MRI) technology. However, traditional magnetic semiconductors can easily generate a spin splitting at the Fermi level and half-metallic electronic occupation, which will sharply reduce the radiation recombination efficiency of photogenerated carriers. To overcome this intrinsic contradiction, we propose a controllable oxidation strategy to introduce some particular PO bonds into black phosphorus nanosheets, in which the p orbital hybridization between P and O atoms not only provides some carrier recombination centers but also leads to a room-temperature spin polarization. As a result, the coexistence of photoluminescence and magnetism is realized in multifunctional black phosphorus probes with excellent biocompatibility. This work provides a new insight into integrating photoluminescence and magnetism together by intriguing atomic orbital hybridization.

Lead-free Na0.5Bi0.5TiO3 (NBT) exhibiting large polarization and a high Curie temperature can be considered as a promising candidate for dielectric capacitors. The large polarization switching hysteresis and low breakdown field, however, restrict the performance optimization. Herein, epitaxial NBT-based high-entropy Na0.5Bi0.5Ti0.7Hf0.1Zr0.1Sn0.1O3 (NBTHZS) films are designed and prepared by solution-based processing. Compared with the NBT film, the polarization switching hysteresis is depressed and the breakdown field is significantly improved for the NBTHZS film due to the high-entropy effects. Therefore, the NBTHZS film achieves a ∼16 times enhancement of energy density (from 5.1 J/cm3 of the NBT film to 81 J/cm3 of the NBTHZS film) and a high efficiency of 74.1% as well as an excellent performance reliability. The results shed light on enhancing dielectric energy storage properties of NBT-based films by forming high-entropy structures.

State-resolved charge exchange (CX) cross sections are of the utmost importance for modeling related photon emissions existing in a broad range of astrophysical environments. With the cold-target recoil-ion momentum spectroscopy, we determined with high accuracy the state-resolved single and double CX cross sections at the quantum orbital angular momentum level for solar wind ion C4+ collisions with He in an energy range of 1.67–20 keV u−1, which allow one to benchmark the CX calculations in great detail, and to test the applicability of the analytical n- and ℓ-distribution models widely adopted by the astrophysical community. We found that the present measurements are well reproduced by the most recent state-of-the-art atomic–orbital close-coupling calculations. However, the CX models failed to give a consistent description on the measured ℓ distributions. The present work reveals that the velocity and collision partner species dependence effects as well as electronic correlations for multielectron processes should be included in an improved model. Alternatively, in future modeling to interpret high-resolution astrophysical observations the more elaborate quantum-mechanical calculations may be resorted to with confidence.

Design and realization of high-efficiency p-type thermoelectric materials with excellent performance are the demand for integrated thermoelectric components. Compared with single crystal bulk materials, thermoelectric thin films are more suitable for the miniaturization of thermoelectric devices. Here, c-axis oriented CuRh1− xMg xO2 (x = 0, 0.05, and 0.1) thin films were prepared and the thermoelectric properties are reported. The power factor of a p-type 10% Mg-doped CuRhO2 thin film shows a large value of 535.7 μW K–2 m-1 at 300 K. The results suggest that the hole-doped CuRhO2 thin films can be regarded as potential p-type thermoelectric oxide and will pave an avenue to develop Rh-based thermoelectric thin films.

CaBi2Nb2O9 ceramics were fabricated via the solid-state reaction method by the addition of B2O3 as a sintering aid at lower sintering temperatures than that prepared without B2O3. Ferroelectricity, piezoelectricity, and resistivity can be still greatly enhanced when the sintering temperature is decreased from 1075 °C for CaBi2Nb2O9 to 975 °C for CaBi2Nb2O9–0.25 wt. % B2O3. The high resistivity and weak c-axis texture ensure that the ceramics can be fully polarized in a high enough electric field. The increased spontaneous ferroelectric and remanent polarization result in a significant enhancement in the piezoelectric properties of CaBi2Nb2O9–0.25 wt. % B2O3. The sample sintered at 975 °C possesses a high piezoelectric coefficient d33 of ∼15.0 pC/N and resistivity of 1.4 × 106 Ω cm (at 600 °C) along with a high ferroelectric Curie temperature TC of ∼954 °C. This work is beneficial for the preparation of high-temperature piezoelectric ceramics with excellent electrical properties at a low sintering temperature.

The traditional strategy for transparent conducting oxides (TCOs) follows the path of chemical design by increasing carrier concentrations in insulators through deliberate doping to coordinate the exclusive properties of electrical conductivity with optical transparency. Despite the success of n-type TCOs, the developed p-type TCOs based on chemical design exhibit much lower performance than the n-type counterparts primarily constrained by the hole doping trouble. Recently, the correlated metal of a V2O3 thin film has been reported as high-performance p-type TCOs with high hole concentration (>1022 cm−3). In this paper, we propose an alternative approach of compressive strain in V2O3 thin films toward further increasing the carrier concentration and, consequently, enhancing the performance of p-type TCOs. The compressive strain of the V2O3 thin film is realized by the lattice mismatch between V2O3 and Al2O3. Interestingly, carrier concentrations in strained V2O3 thin films can be increased by several times exceeding 1023 cm−3, which directly correlates with the increase (decrease) in [Formula: see text] ([Formula: see text]) orbital occupation as verified by the Raman spectrum. Meanwhile, the screened plasma energy of a strained V2O3 thin film shifts to ∼1.6 eV, which is less than 1.75 eV to assure the opening of the transparency window in the visible region. As a result, strained V2O3 thin films exhibit enhanced performance as p-type TCOs with relatively high figure of merit. These results indicate that the structural modification can open up an effective approach for increasing the carrier concentration and enhancing the performance of p-type TCOs.

We report a cluster spin glass behavior, multiferroicity and magnetoelectric (ME) effects in the single crystals of 0.46[Formula: see text]-0.54[Formula: see text]. The crystals are found to possess a pseudo-cubic structure with a weak tetragonal distortion and show ferroelectricity at room temperature with a ferroelectric curie temperature of [Formula: see text] K. The cluster spin glass state in the crystal is evidenced by detailed dc and ac magnetic experiments, including thermo-remnant magnetization, aging effect, memory effect, etc. Magnetodielectric effects, poling enhanced magnetism, and electric field induced acceleration of magnetization relaxation in the spin glass state are observed and ascribed mainly to spin-lattice coupling. These results might suggest an effective route to improve ferromagnetism and ME effects by constructing a spin glass state in [Formula: see text]-based antiferromagnetic multiferroics.

Long noncoding RNAs (lncRNAs) play crucial roles in the development of human cancers. LncRNA small nucleolar RNA host gene 20 (SNHG20) has been reported to be an oncogene in several cancers, whereas the specific role of SNHG20 in glioblastoma is unclear. In this study, we found that SNHG20 was significantly upregulated in glioblastoma tissues and cell lines. Survival analysis suggested that high expression of SNHG20 indicated the low overall survival rate of glioblastoma patients. Subsequently, gain or loss-of-function assays were carried out to examine the effect of SNHG20 on glioblastoma cell proliferation and apoptosis. We found that SNHG20 knockdown obviously suppressed cell proliferation, increased cell apoptosis and impaired stem properties, while SNHG20 overexpression led to the opposite results. In vivo experiment demonstrated that knockdown of SNHG20 efficiently suppressed cell growth in vivo. Furthermore, western blotting demonstrated that the PI3K/Akt/mTOR signaling pathway was activated by SNHG20 in glioblastoma cells. At last, rescue assays validated that PI3K/Akt/mTOR signaling pathway involved in the glioblastoma progression mediated by SNHG20. Taken together, this study revealed that SNHG20 regulated PI3K/Akt/mTOR signaling pathway to promote tumorigenesis and stemness of glioblastoma.

Topological semimetals (TSMs) present intriguing quantum states and have attracted much attention in recent years because of exhibiting various anomalous magneto-transport phenomena. Theoretical prediction shows that some novel phenomena, such as negative magnetoresistance (MR) and the planar Hall effect (PHE), originate from the chiral anomaly in TSMs. In this work, high-field (33 T) Shubnikov-de Haas (SdH) oscillations are obtained to reveal the topology of PtSn

Circulating microRNAs (miRNAs) are promising biomarkers for the diagnosis and prognosis prediction of cancer. In the study, we aimed to investigate the potential clinical significance of the plasma miR-25 in non-small cell lung carcinoma (NSCLC).We first compared the miRNAs expression pattern between NSCLC tissues and adjacent normal tissues then, bioinformatic analysis of the downstream targets of miR-25 was performed. The diagnostic and prognostic value of the plasma miR-25 in NSCLC was then evaluated.The expression level of miR-25 was increased in NSCLC tissues compared to the adjacent normal tissues. In addition, bioinformatic analysis of the downstream-targeted genes of miR-25 revealed that many gene ontology functions and pathways were associated with cancer progression. The levels of plasma miR-25 were significantly upregulated in NSCLC patients compared to normal controls. In addition, the plasma miR-25 levels were especially higher in NSCLC patients with positive lymph node metastasis, poorly differentiation or advanced clinical stage. Subsequently, we found that the plasma miR-25 expression levels were dramatically decreased in 45 NSCLC patients after receiving surgical treatment. The receiver operating characteristic (ROC) curve analysis indicated that the plasma miR-25 exhibited high diagnostic sensitivity and specificity to discriminate NSCLC cases from healthy subjects. More interestingly, the combination of the plasma miR-25 and carcinoembryonic antigen (CEA) could effectively enhance the accuracy for distinguishing NSCLC patients from normal controls. Moreover, the plasma miR-25 overexpression was closely correlated with aggressive clinical characteristics and poor survival. Finally, the plasma miR-25 was identified as an independent prognostic marker for the overall survival of NSCLC.Collectively, our findings demonstrated that the plasma miR-25 might serve as a novel promising biomarker in the diagnosis and prognosis prediction of NSCLC.

A mid-wavelength $$128 \times 128$$ infrared focal plane arrays based on InAs/GaSb type-II superlattice was presented in this work. Superlattice materials were grown on GaSb substrates using MBE technology, which was confirmed by XRD, TEM and AFM analyses. Absorber structure for mid-wavelength detector was designed to be 8 ML InAs/8 ML GaSb. The pixel of the detector had a conventional PIN structure with a size of $$50\,\upmu \hbox {m}\times 50\,\upmu \hbox {m}$$ . The device fabrication process consisted of mesa etching, side-wall passivation, metallization, and flip-chip hybridization with readout integrated circuit, epoxy backfill, lap, and polish. The dark current I–V curve was measured from 77 K up to 297 K. The responsivity spectra, photoluminescence peak wavelength and blackbody current responsivity were measured at 77 K. The detector had a cut-off wavelength of $$4.8\,\upmu \hbox {m}$$ , photoluminescence peak wavelength of $$4.4\,\upmu \hbox {m}$$ , peak detectivity of $$7.1\times 10^{11}\,\hbox {cm}\,\hbox {Hz}^{1/2}\,\hbox {W}^{-1}$$ , quantum efficiency of 50 %. The PIN diode may reach a typical value of $$\hbox {R}_{0}\hbox {A}$$ of $$5.0\times 10^{5}\Omega \,\hbox {cm}^{2}$$ . Pixel operability of the detector was more than 98 %, the non-uniformity was 4.3 %, and the mean NETD value was lower than 20 mK. Concept proof of infrared imaging was also demonstrated with the focal plane array at 77 K.

In the sake of connecting the charge-density-wave (CDW) of TaSe$_2$ and single-\emph{\textbf{q}} CDW-type distortion of TaTe$_2$, we present an overall electronic phase diagram of 1\emph{T}-TaSe$_{2-x}$Te$_x$ ($0 \leq x \leq 2$). In the experimentally prepared single crystals, the CDW is completely suppressed as $0.5 < x < 1.5$, while superconductivity emerges as $0.2 < x < 1.2$. Theoretically, similar to 1\emph{T}-TaSe$_2$ and 1\emph{T}-TaTe$_2$, the hypothetic 1\emph{T}-TaSeTe with ordered Se/Ta/Te stacking shows instability in the phonon dispersion, indicating the presence of CDW in the ideally ordered sample. The contradictory between experimental and theoretical results suggests that the CDW is suppressed by disorder in 1\emph{T}-TaSe$_{2-x}$Te$_x$. The formation and suppression of CDW are found to be independent with Fermi surface nesting based on the generated electron susceptibility calculations. The calculation of phonon linewidth suggests the strong \textbf{\emph{q}}-dependent electron-phonon coupling induced period-lattice-distortion (PLD) should be related to our observation: The doping can largely distort the TaX$_6$ (X = Se, Te) octahedra, which are disorderly distributed. The resulted puckered Ta-Ta layers are not compatible with the two-dimensional PLD. Therefore, CDW is suppressed in 1\emph{T}-TaSe$_{2-x}$Te$_x$. Our results offer an indirect evidence that PLD, which can be influenced by strong disorder, is the origin of CDW in the system.

Recently, Bi-based compounds have attracted attentions because of the strong spin-orbit coupling (SOC). In this work, we figured out the role of SOC in ABi3 (A = Sr and Ba) by theoretical investigation of the band structures, phonon properties, and electron-phonon coupling. Without SOC, strong Fermi surface nesting leads to phonon instabilities in ABi3. SOC suppresses the nesting and stabilizes the structure. Moreover, without SOC the calculation largely underestimates the superconducting transition temperatures (Tc), while with SOC the calculated Tc are very close to those determined by measurements on single crystal samples. The SOC enhanced superconductivity in ABi3 is due to not only the SOC induced phonon softening, but also the SOC related increase of electron-phonon coupling matrix elements. ABi3 can be potential platforms to construct heterostructure of superconductor/topological insulator to realize topological superconductivity.

Tunneling spectra of near optimally doped, submicron Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ intrinsic Josephson junctions are presented, and examined in the region where the superconducting gap evolves into pseudogap. The spectra are analyzed using a self-energy model, proposed by Norman {\it et al.}, in which both quasiparticle scattering rate $\Gamma$ and pair decay rate $\Gamma_{\Delta}$ are considered. The density of states derived from the model has the familiar Dynes' form with a simple replacement of $\Gamma$ by $\gamma_+$ = ($\Gamma$ + $\Gamma_{\Delta}$)/2. The $\gamma_+$ parameter obtained from fitting the experimental spectra shows a roughly linear temperature dependence, which puts a strong constraint on the relation between $\Gamma$ and $\Gamma_{\Delta}$. We discuss and compare the Fermi arc behavior in the pseudogap phase from the tunneling and angle-resolved photoemission spectroscopy experiments. Our results indicate an excellent agreement between the two experiments, which is in favor of the precursor pairing view of the pseudogap., Comment: 7 pages, 6 figures

The mesoporous nanocomposite fabricated by self-assembly has many unique properties compared with the original materials. In2O3 (IO) and In2O3–SnO2 (ITO) in mesoporous silica were studied in the present paper. They were self-assembled in a nanoscale mesoporous silica by an adsorption–annealing process. The composite of IO and ITO in mesoporous silica was characterised by transmission electron microscopy, atomic force microscopy and nitrogen sorption isotherms. Photoluminescence spectra of the samples were measured by a fluorescence spectrophotometer. The results show that the composite was synthesised from IO and ITO in a nano-scale mesoporous silica with assembly structure, and bulk mesoporous silica is easier to be loaded by the particles than the sheet one, but the specific surface area decreases with increasing atomic weight of the substances loaded in silica mesoporous. The results also show that the mesoporous composite doped with some substance may enhance the effect of photoluminescence. F...

Background: Henoch Schonlein Purpura (HSP) is a systemic vasculitic disease which is common in children. It is very important to understand the clinical features of this disease for doctors and nurses. Objectives: To study the clinical characteristics of HSP in children. Methods: Collect the clinical data of the HSP children, and analyze the clinical characteristics of these HSP patients. Results: The ratio of M:F was 1.9:1. The mean age was 6.6 ± 1.6 years. The typical onset seasons were spring, winter and autumn. Infection and food allergy were the main etiological factors. The first symptom was skin purpura and these purpura mainly concentrated the lower extremities and buttocks. The dominant digestive clinical features were abdominal pains and vomiting. The knee joint and ankle joint were most frequently affected. The typical kidney symptoms were microscopic hematuria and albuminuria. An increased ESR was reported in 68 patients (56.7%). Serum C3 decreased in 13 cases (10.8%). ASO titer was higher in 57 children (47.5%). Conclusion: There were gender, season and area differences for the HSP patients. The etiological factors were diverse. HSP patients could have various clinical symptoms and rare complications. Key words: Henoch Schonlein Purpura, Children

Azoospermia factor (AZF) genes on the long arm of the human Y chromosome are involved in spermatogenesis, and microdeletions in the AZF region have been recognised to be the second major genetic cause of spermatogenetic failure resulting in male infertility. While screening for these microdeletions can avoid unnecessary medical and surgical treatments, current methods are generally time-consuming. Therefore, we established a new method to detect and analyse microdeletions in the AZF region quickly, safely and efficiently. In total, 1,808 patients with spermatogenetic failure were recruited from three hospitals in southern China, of which 600 patients were randomly selected for screening for Y chromosome microdeletions in AZF regions employing real-time polymerase chain reaction with a TaqMan probe. In our study, of 1,808 infertile patients, 150 (8.3%) were found to bear microdeletions in the Y chromosome using multiplex PCR, while no deletions were found in the controls. Among the AZF deletions detected, two were in AZFa, three in AZFb, 35 in AZFc, three in AZFb+c and two in AZFa+b+c. Our method is fast-it permits the scanning of DNA from a patient in one and a half hours-and reliable, minimising the risk of cross-contamination and false-positive and false-negative results.

To identify the potential role of macrophage inflammatory protein-1α (MIP-1α) with its C-C chemokine receptor 5 (CCR5) in epileptogenic brain injury, we examined their expression in juvenile rat hippocampus and explored the potential link between MIP-1α, CCR5 and neuropathological alterations after status epilepticus (SE) induced by intracerebroventricular (i.c.v.) kainic acid (KA) injection.Based on the determination of the development of spontaneous seizures initiated by SE in developing rat brain, we firstly examined hippocampal neurone damage through Nissl and Fluoro-Jade B staining, and evaluated microglial reaction during the early phase following KA-induced SE in 21-day-old rats. MIP-1α and CCR5 protein were quantified by ELISA and Western blot respectively following mRNA by real-time PCR. We also mapped MIP-1α and CCR5 expression in the hippocampus by immunohistochemistry and identified their cellular sources using double-labelling immunofluorescence.In juvenile rats, KA caused characteristic neurone damage in the hippocampal subfields, with accompanying microglial accumulation. In parallel with mRNA expression, MIP-1α protein in hippocampus was transiently increased after KA treatment, and peaked from 16 to 72 h. Double-labelling immunofluorescence revealed that MIP-1α was localized to microglia. Up-regulated CCR5 remained prominent at 24 and 72 h and was mainly localized to activated microglia. Further immunohistochemistry revealed that MIP-1α and CCR5 expression were closely consistent with microglial accumulation in corresponding hippocampal subfields undergoing degenerative changes.Our data indicated that MIP-1α as a regulator, linking with the CCR5 receptor, may be involved within the early stages of the epileptogenic process following SE by i.c.v. KA injection.

The anisotropic superconducting state properties in Cu0.03TaS2 have been investigated by magnetization, magnetoresistance, and specific heat measurements. It clearly shows that Cu0.03TaS2 undergoes a superconducting transition at TC = 4.03 K. The obtained superconducting parameters demonstrate that Cu0.03TaS2 is an anisotropic type-II superconductor. Combining specific heat jump = 1.6(4), gap ratio 2/kBTC = 4.0(9) and the estimated electron-phonon coupling constant ~ 0.68, the superconductivity in Cu0.03TaS2 is explained within the intermediate coupling BCS scenario. First-principles electronic structure calculations suggest that copper intercalation of 2H-TaS2 causes a considerable increase of the Fermi surface volume and the carrier density, which suppresses the CDW fluctuation and favors the raise of TC., 16pages, 5figures

We report on the first unambiguous observation of macroscopic quantum tunneling (MQT) in a single submicron Bi(2)Sr(2)CaCu(2)O(8+delta) surface intrinsic Josephson junction (IJJ) by measuring its temperature-dependent switching current distribution. All relevant junction parameters were determined in situ in the classical regime and were used to predict the behavior of the IJJ in the quantum regime via MQT theory. Experimental results agree quantitatively with the theoretical predictions, thus confirming the MQT picture. Furthermore, the data also indicate that the surface IJJ, where the current flows along the c axis of the crystal, has the conventional sinphi current-phase relationship.

Two new pregnane-type steroidal glycosides, pregna-5,20-dien-3-O-alpha-fucopyranoside (1) and pregna-20-en-3-O-alpha-fucopyranoiside (2), along with two known pregnane derivatives, were isolated from the soft coral Cladiella krempfi. Their structures were determined by spectroscopic data analysis.

Echinocandins and triazoles were proven to be effective antifungal drugs against invasive fungal infections (IFI), which may cause significant morbidity and mortality in immunocompromised patients. The aim of this study was to compare the efficacy and safety between echinocandins and triazoles for the prophylaxis and treatment of fungal infections. PubMed, Embase, and the Cochrane Library were searched to identify relevant randomized controlled trials (RCTs) up to July 2014. The quality of trials was assessed with the Jadad scoring system. The primary outcomes of interest were treatment success, microbiological success, breakthrough infection, drug-related adverse events (AEs), withdrawals due to AEs, and all-cause mortality. Ten RCTs, involving 2,837 patients, were included, as follows: caspofungin versus fluconazole (n = 1), caspofungin versus itraconazole (n = 1), anidulafungin versus fluconazole (n = 1), micafungin versus fluconazole (n = 4), micafungin versus voriconazole (n = 2), and micafungin versus itraconazole (n = 1). Echinocandins and triazoles showed similar effects in terms of favorable treatment success rate [relative risk (RR) = 1.02, 95 % confidence interval (CI), 0.97–1.08], microbiological success rate (RR = 0.98, 95 % CI, 0.90–1.15), breakthrough infection (RR = 1.09; 95 % CI, 0.59–2.01), drug-related AEs (RR = 0.94; 95 % CI, 0.71–1.15), and all-cause mortality (RR = 0.85; 95 % CI, 0.66–1.10) in the prophylaxis and treatment of fungal infections. Additionally, echinocandins were more effective than triazoles for prophylaxis in patients undergoing hematologic malignancies or those who received hematopoietic stem cell transplantation (HSCT; RR = 1.08; 95 % CI, 1.02–1.15). Echinocandins significantly decreased the AE-related withdrawals rate compared with triazoles (RR = 0.47; 95 % CI, 0.33–0.67). This meta-analysis revealed that echinocandins are as effective and safe as triazoles for the prophylaxis and treatment of patients with fungal infections.