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We demonstrate a nonlinearity optimization method by altering distribution of passive fibers in a dissipative-soliton mode-locked fiber laser to level up output parameters. In the numerical simulation, we found that the passive fiber segment after gain fiber characterizes the highest average B-integral among fiber segments. By reducing the length of this fiber section and keeping the total passive fiber length as constant, the output pulse energy can be effectively scaled up while maintaining a short dechirped pulse duration, resulting in boosting peak power. With this method, 37-nJ pulses are generated from a dissipative-soliton mode-locked cladding pumped ytterbium-doped single-mode fiber laser in the experiment. The pulse can be dechirped to 66 fs with 350 kW peak power. Moreover, the pulse pedestal is suppressed by a vector-dispersion compressor.
The transition metal compound catalysts have been taken a great part in renewable energy conversion and storage systems. Herein, we report the uniform CoFe2O4 nanoparticles with abundant oxygen vacancies and specific active surface exposed through the simple hydrothermal reaction for improving the electrocatalytic performance and stability. They show good electrocatalytic performance for hydrogen evolution reaction in 0.5 M H2SO4 with an onset potential of 20 mV, the overpotential of 45 mV (at j = 10 mA/cm2), and remarkable long-term stability more than 100 h at different current densities and better oxygen reduction reaction activity with lower overpotential in 0.1 M KOH. Moreover, the home-made primary Zn–air batteries, using CoFe2O4 nanoparticles as an air–cathode display the high open-circuit voltage of 1.47 V and the maximum power density of 142 mW/cm2. The two-series-connected batteries fabricated by CoFe2O4 nanoparticles can support a light-emitting diode to work for more than 48 h.
The beginning of the transition from the laminar to a turbulent flow is usually the generation of instability Tollmien-Schlichting (T-S) waves in the boundary layer. Previously, most numerical and experimental researches focused on generating instability T-S waves through the external disturbances such as acoustic waves and vortical disturbances interacting with wall roughness or at the leading-edge of flatplate, whereas only a few paid attention to the excitation of the T-S waves directly by free-stream turbulence (FST). In this study, the generating mechanism of the temporal mode T-S waves under free-stream turbulence is investigated by using direct numerical simulation (DNS) and fast Fourier transform. Wave packets superposed by a group of stability, neutral and instability T-S waves are discovered in the boundary layer. In addition, the relation between the amplitude of the imposed free-stream turbulence and the amplitude of the excited T-S wave is also obtained.
We present results of current measurements on the super-sensitive mini-cyclotron as an accelerator mass spectrometer, successfully developed at Shanghai Institute of Nuclear Research (SINR). We describe new ideas and unique techniques adopted for increasing the transmission efficiency in the injection, acceleration and extraction region, for eliminating various backgrounds and for improving the precision of 14C analysis, which have led to the breakthrough of our Shanghai Mini-Cyclotron Accelerator Mass Spectrometry project. We also discuss further development of the prototype facility.
Environmental filtering and competitive interactions are important ecological processes in community assembly. The contribution of the two processes to community assembly can be evaluated by shifts in functional diversity patterns. We examined the correlations between functional diversity of six traits (leaf chlorophyll concentration, dry matter content, size, specific leaf area, thickness and wood density) and environmental gradients (topography and soil) for 92 species in the 20-ha Dinghushan forest plot in China. A partial Mantel test showed that most of the community-weighted mean trait values changed with terrain convexity and soil fertility, which implied that environmental filtering was occurring. Functional diversity of many traits significantly increased with increasing terrain convexity and soil fertility, which was associated with increased light and below-ground resources respectively. These results suggest that co-occurring species are functionally convergent in regions of strong abiotic stress under the environmental filtering, but functionally divergent in more benign environments due to resource partitioning and competitive interactions. Single-trait diversity and multivariate functional diversity had different relationships with environmental factors, indicating that traits were related to different niche axes, and associated with different ecological processes, which demonstrated the importance of focusing niche axes in traits selection. Between 9% and 41% of variation in functional diversity of different traits was explained by environmental factors in stepwise multiple regression models. Terrain convexity and soil fertility were the best predictors of functional diversity, which contributed 30.5% and 29.0% of total R2 to the model. These provided essential evidence that different environmental factors had distinguishing impacts on regulating diversity of traits.
We find that for the galaxy groups, the luminosity gap between the brightest and the subsequent brightest member galaxies in a halo (group) can be used to significantly reduce the scatter in the halo mass estimation based on the luminosity of the brightest galaxy alone. These corrections can significantly reduce the scatter in the halo mass estimations by ~ 50% to ~ 70% in massive halos.
We show that Artin–Schelter regularity of a
-graded algebra can be examined by its associated
r-graded algebra. We prove that there is exactly one class of four-dimensional Artin–Schelter regular algebras with two generators of degree one in the Jordan type. This class is strongly noetherian, Auslander regular, and Cohen–Macaulay. Their automorphisms and point modules are described.
A high-order numerical method for three-dimensional hydrodynamics is presented. The present method applies high-order compact schemes in space and a Runge-Kutta scheme in time to solve the Reynolds-averaged Navier-Stokes equations with the k-ε turbulence model in an orthogonal curvilinear coordinate system. In addition, a two-dimensional equation is derived from the depth-averaged momentum equations to predict the water level. The proposed method is first validated by its application to simulate flow in a 180° curved laboratory flume. It is found that the simulated results agree with measurements and are better than those from SIMPLEC algorithm. Then the method is applied to study three-dimensional hydrodynamics in a natural river, and the simulated results are in accordance with measurements.
Tramadol hydrochloride (HCl) is a centrally acting synthetic opioid analgesic. Psychotic symptoms are relatively rare in reported adverse events. Here, we report a patient who presented with tramadol-related psychotic symptoms.
A 59-year-old female had underlying bipolar I disorder and received lithium treatment with stable affective status. 1 month before hospitalisation, she had been taking tramadol HCl/acetaminophen for joint pain. She then developed obvious persecutory delusion. However, her clinical picture did not meet the criteria of any mood episode. After treatment of risperidone in addition to lithium, she was discharged without any psychotic symptom. She remained euthymic without any psychotic symptom on monotherapy of lithium (300 mg) three tablets once daily.
Tramadol HCl is commonly prescribed in clinical practice and psychotic symptoms related to it are uncommon. We should be careful about the rare but important adverse events while prescribing tramadol HCl.
This study identified possible risk factors for newly diagnosed mood disorders, including depressive and bipolar disorders, in prostate cancer patients.
From 2000 to 2006, two cohorts were evaluated on the occurrence of mood disorder diagnosis and treatment. For the first cohort, data of patients diagnosed with prostate cancer was obtained from the Taiwan National Health Insurance (NHI) Research Database. As the second cohort, a cancer-free comparison group was matched for age, comorbidities, geographic region, and socioeconomic status.
Final analyses involved 12,872 men with prostate cancer and 12,872 matched patients. Increased incidence of both depressive (IRR 1.52, 95% CI 1.30–1.79, P <0.001) and bipolar disorder (IRR 1.84, 95% CI 1.25–2.74, P = 0.001) was observed among patients diagnosed with prostate cancer. Multivariate matched regression models show that cerebrovascular disease (CVD) and radiotherapy treatment could be independent risk factors for developing subsequent depressive and bipolar disorders.
We observed that the risk of developing newly diagnosed depressive and bipolar disorders is higher among Taiwanese prostate cancer patients. Clinicians should be aware of the possibility of increased depressive and bipolar disorders among prostate cancer patients in Taiwan. A prospective study is necessary to confirm these findings.
We introduce a method named homogeneous PBW deformation that preserves the regularity and some other homological properties for multigraded algebras. The method is used to produce Artin–Schelter regular algebras without the hypothesis on grading.
Plasmonic Ag nanoparticles (AgNPs) with narrow distribution were successfully loaded on graphitic carbon nitride (g-C3N4) sheet by thermal polymerization of melamine precursor and a simple wet-chemical pathway in the presence of polyvinylpyrrolidone (PVP). N,N-dimethylformamide (DMF) was used as an efficient reducing agent as well as a solvent and its presence facilitated homogeneous distribution of AgNPs under mild reaction condition and easy control of its particle growth under different precursor amounts. Ag/g-C3N4 composites of different Ag content were prepared, and the phase, chemical structure, morphologies, electronic and optical properties of Ag/g-C3N4 heterostructures were well characterized, respectively. The photocatalytic activity of Ag/g-C3N4 composites was evaluated by the decolorization of methyl orange (MO), and they exhibited superior photocatalytic activity to bulk g-C3N4 under visible-light irradiation. Influence of Ag content to photocatalytic activity was also discussed and possible mechanism was explored based on the analysis of photoluminescence spectra (PL) and photodecoloration activity.
In this paper, we present a detailed study of high quality (110) ZnO films, epitaxially grown on R-plane sapphire substrates by metal-organic chemical vapor deposition (MOCVD). The epitaxial relationships are (11
0 ) ZnO//( 01 2 ) Al2O3 and  ZnO// Al2O3 as confirmed by X-ray diffraction (θ-2θ, and ϕ-scan) and high-resolution cross-sectional transmission electron microscopy (HR-TEM). Low temperature photoluminescence (PL) indicates the ZnO thin films are almost strain free. Optical absorption and reflection measurements with linearly polarized light indicate a strong optical anisotropy. The polarization rotation towards the C-axis associated with the optical anisotropy is utilized to demonstrate an optically addressed ultra-fast, ultraviolet light modulator.
Epitaxial lateral overgrowth (ELO) of GaN on SiO2-masked (0001) GaN substrates has been investigated by using chloride-based growth chemistries via hydride vapor phase epitaxy (HVPE) and metal organic vapor phase epitaxy (MOVPE). Diethyl gallium chloride, (C2H5)2GaCl, was used in as the MOVPE Ga precursor. The lateral and vertical growth rates as well as the overgrowth morphology of ELO GaN structures are dependent on growth temperature, V/III ratio and the in-plane orientation of the mask opening. A high growth temperature and low V/III ratio increase the lateral growth rate and produce ELO structures with a planar surface to the GaN prisms. High-quality coalesced and planar ELO GaN has been fabricated by both growth chemistries. The use of the diethyl gallium chloride source allows for the benefits of HVPE growth to be realized within the MOVPE growth environment.
A study of 7,388 consecutive patients after hepatic resection between 2011 and 2012 identified hepatolithiasis, cirrhosis, and intraoperative blood transfusion as the only independent risk factors of both incisional and organ/space surgical site infection (SSI). Patients with these conditions should be cared for with caution to lower SSI rates.
An in situ redox reaction was developed to synthesize bundled tungsten oxide (WO3@W18O49) ultrafine nanowires (BUNs) loaded with Ag nanoparticles using weakly reductive W18O49 and oxidative silver nitrate as precursor. However, due to the weak activation between the two reactants, redox just happened on the surface of W18O49, resulting in the formation of W18O49 coated with WO3 (here, we refer this structure to WOx simply), and the bulk phase of the composites retained the same pattern. Ag nanoparticles (<5 nm) with a narrow size distribution were obtained and immobilized onto WOx BUNs without any aggregation. The paper presented a systematic investigation on the Ag-WOx nanocomposite used as a catalyst for the reduction of p-nitrophenol and as an antibacterial agent against Escherichia coli. The remarkably enhanced performance may be ascribed to the moderate interaction of the small Ag-NPs and WOx BUNs with high specific surface area.
The AlGaN/GaN/InGaN/GaN double heterojunction high electron mobility transistors (DH-HEMTs) sample has been grown by MOCVD on (0 0 0 1) sapphire substrate. The structure features a 7 nm In0.046Ga0.954N interlayer determined by Rutherford backscattering (RBS). Since the polarization field in the InGaN interlayer is opposite to it in the AlGaN layer, an additional potential barrier is introduced between the two-dimensional electron gas (2DEG) channel and buffer, leading to enhanced carrier confinement and improved buffer isolation. The GaN layers between the AlGaN layer and InGaN interlayer are divided into two layers consisting of GaN channel layer which provides high mobility 2DEG grown at 1070 °C and GaN spacer layer grown at the same temperature as InGaN interlayer (800 °C) to prevent indium diffusion. RBS measurement confirms that the 3 nm GaN spacer layer isolates the InGaN interlayer well and free from diffusion. Hall measurement has been performed, the mobility as high as 1552 cm2/V s at room temperature is obtained and the sheet carrier density is 1.55 × 1013 cm−2. The average sheet resistance is 331 Ω/sq, respectively. The mobility obtained in this paper is about 20% higher than similar structures reported.
Dating middle Pleistocene hominin occupations alongside the reconstruction of paleoenvironments in China between 700 and 100 ka has always been a challenging task. In this paper, we report thermally transferred optically stimulated luminescence (TT-OSL) dating results for a Middle Paleolithic site in the Luonan Basin, central China, which we have named Longyadong Cave. The results suggest that the age of cave infilling and the deposition of sediments outside the cave range between 389 ± 18 and 274 ± 14 ka. These deposits are stratigraphically and geochronologically correlated with the L4 loess and S3 paleosol units of the typical loess–paleosol sequence of the Chinese Loess Plateau, and with Marine Isotope Stages (MIS) 10 to 9, respectively. On the basis of these new ages and the available paleoenvironmental data, it is suggested that the Longyadong hominins might have occupied the site both in glacial and interglacial periods, demonstrating that they coped well with environmental change in this mountainous region in warm/wet and cold/dry climates. The study further implies that the hominins abandoned the Longyadong Cave between 274 ± 14 and 205 ± 19 ka, when it was sealed by alluvial and slope deposits.
Previous studies support Beck's cognitive model of vulnerability to depression. However, the relationship between his cognitive triad and other clinical features and risk factors among those with major depression (MD) has rarely been systematically studied.
The three key cognitive symptoms of worthlessness, hopelessness and helplessness were assessed during their lifetime worst episode in 1970 Han Chinese women with recurrent MD. Diagnostic and other risk factor information was assessed at personal interview. Odds ratios (ORs) were calculated by logistic regression.
Compared to patients who did not endorse the cognitive trio, those who did had a greater number of DSM-IV A criteria, more individual depressive symptoms, an earlier age at onset, a greater number of episodes, and were more likely to meet diagnostic criteria for melancholia, postnatal depression, dysthymia and anxiety disorders. Hopelessness was highly related to all the suicidal symptomatology, with ORs ranging from 5.92 to 6.51. Neuroticism, stressful life events (SLEs) and a protective parental rearing style were associated with these cognitive symptoms.
During the worst episode of MD in Han Chinese women, the endorsement of the cognitive trio was associated with a worse course of depression and an increased risk of suicide. Individuals with high levels of neuroticism, many SLEs and high parental protectiveness were at increased risk for these cognitive depressive symptoms. As in Western populations, symptoms of the cognitive trio appear to play a central role in the psychopathology of MD in Chinese women.