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In order to understand the impact of nano-crystallites on current transport mechanisms in screen-printed c-Si solar cells with lowly-doped emitter, Te-glass based Ag pastes with different transition temperatures (Tg) were used. The Te-glass with lower Tg showed lower Rc than the one with higher Tg due to the formation of nano-crystallites in the glass layer. These nano-crystallites enhance the conductivity of the glass and lead to higher fill factor (FF). The nature of these nano-crystallites was first identified by the Raman spectrometry and the peaks at 76 cm-1, 119 cm-1 and 145 cm-1 were corresponding to Ag2Te and PbTe. The conductive-AFM further confirmed the high conductivity of these nano-crystallites without pyramidal Ag crystallites, which means the current transporting from Si emitter to Ag gridlines is mainly through the nano-crystallites in the glass.
Given the global water challenges, solar-driven steam generation has become a renewed topic recently as an energy-efficient way for clean water production. Here, a hybrid plasmonic structure consisting of a top layer of TiN nanoparticles (NPs) and a bottom layer of mesoporous anodized alumina membrane (AAM) was rationally designed and fabricated. The top TiN NPs with broadband light absorption acted as a plasmonic heating layer, which converted the absorbed light to heat efficiently for interfacial water heating. The AAM acted as the mechanical support layer, guaranteeing the heat isolation and continuous water replenishment. With optimized thickness of the TiN top layer, a solar steam generation efficiency of 87.7% was achieved in this study. This efficiency is comparable or even higher than prior studies. The current work proves the capability of the TiN NPs as an alternative photothermal material.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
In the past few years, we have performed a 22 GHz H2O maser survey towards hundreds of BGPS sources using the 25-meter Nanshan Radio Telescope (NSRT) of the Xinjiang Astronomical Observatory, and detected more than one hundred masers. Our aim is to study star formation activities associated with these sources, as well as search for any correlations that may exist between 22 GHz H2O masers and the evolutionary stage of high-mass star formation regions. The NSRT has been upgraded and have now an effective diameter of 26 meter. Besides, cryogenically cooled dual-beam receiver systems covering seven millimeter-wave observing bands have been installed on the NSRT. For the next step of maser observation, we will continue to do H2O and SiO masers survey of massive dust clumps and monitor some maser sources.
Babesiosis is an emerging tick-transmitted zoonosis prevalent in large parts of the world. This study was designed to determine the rates of Babesia microti infection among small rodents in Yunnan province, where human cases of babesiosis have been reported. Currently, distribution of Babesia in its endemic regions is largely unknown. In this study, we cataloged 1672 small wild rodents, comprising 4 orders, from nine areas in western Yunnan province between 2009 and 2011. Babesia microti DNA was detected by polymerase chain reaction in 4·3% (72/1672) of the rodents analyzed. The most frequently infected rodent species included Apodemus chevrieri and Niviventer fulvescens. Rodents from forests and shrublands had significantly higher Babesia infection rates. Genetic comparisons revealed that Babesia was most similar to the Kobe- and Otsu-type strains identified in Japan. A variety of rodent species might be involved in the enzootic maintenance and transmission of B. microti, supporting the need for further serological investigations in humans.
An apparatus design is described. It is for detecting VHE gamma ray point sources by means of the atmospheric Cerenkov technique. Obviously, the improvement of flux sensitivity and discrimination between gamma ray and isotropic proton showers is still a key problem. Of course, it is necessary to set up more observatories and to track an object continuously with several facilities. With this in mind, we decided to develop an experiment for observing VHE gamma ray sources in China. As a first step, we will set up an apparatus which consists of three 1.5 m diameter searchlight morrors at Xinglong station of Beijing Observatory, Xinglong county, Hebei province (40°. 4N, 117°.5E, altitude 940 m). The observation will start in 1988. Then, the second apparatus will be set up at Delingha station of Purple Mountain Observatory, Delingha county, Qinghai porvince (37°.22N, altitude 3204 m). Both the sites are far from air and light pollution, and have suitable meteological condition for Cerenkov light detection as well as quite convenient facilities for transportation. Some probable technical improvements are also discussed in this paper.
Methods for promoting individuals’ pro-environmental behaviours are becoming very important. Besides traditional factors relevant to pro-environmental actions, few studies have examined the licensing effect within this domain. Across three studies we have explored whether the licensing effect really exists in pro-environmental behaviours, how this effect actually works, and how to inhibit or even avoid this effect. Results have revealed that previous pro-environmental behaviours lead to a decrease in subsequent pro-environmental behaviours, indicating a licensing effect. Also, the licensing effect in pro-environmental behaviours can be explained by having individuals focus on goal progress and reduced by focusing on goal commitment. Furthermore, attributional recall could be an intervention for mitigating the licensing effect.
Zircon U–Pb dating and whole-rock geochemical analysis have been performed on Late Jurassic – Early Cretaceous intrusive rocks of the Ulanhot area, NE China, with the aim of constraining the tectonic evolution of the central and southern Da Xingan Range. Zircon U–Pb dating indicates that Late Jurassic – Early Cretaceous magmatic events experienced four stages at: c. 155 Ma; c. 144 Ma; 135–130 Ma; and c. 126 Ma. The c. 155 Ma magmatic event consists of quartz diorite and granite-porphyryp with the geochemical characteristic of high Sr and Sr/Y or high A/CNK (1.38), implying the primary magma was derived from partial melting of a thickened lower crust which induced the closure of the Mongol–Okhotsk Ocean. The c. 144 Ma magmatic event consists of quartz monzodiorite with the geochemical characteristics of alkaline series, and indicates the delamination of a thickened crust. The 135–130 Ma magmatic event consists of syenogranite and granite-porphyry with characteristics of both I-type and A-type granites, which induced both the subduction of the Palaeo-Pacific oceanic plate and the post-orogenic extension of the Mongol–Okhotsk Orogenic Belt. The c. 126 Ma magmatic event consisted of highly fractionated I-type biotite granite and alkaline series gabbro, marking the end of the Mongol–Okhotsk Orogen, and implying that the study area was controlled by the circum-Pacific tectonic system during this stage.
The effect of electropulsing assisted ultrasonic surface modification (EUSM) on microstructure and surface properties of S50C steel welded components is investigated. Compared with conventional ultrasonic surface modification (USM) process, EUSM process achieves significant improvements in microstructure, including deeper strengthened layers and gradient microstructure on the surface. The EUSM-induced microstructure results in higher levels of surface compressive residual stress and greater surface microhardness and its effective depth. Conventional USM process is inevitably accompanied by some plastic damages, such as pit and crack defects. The damages, however, can be eliminated to some extent during the EUSM process. These enhancements may be attributed to the thermal and athermal effects caused by electropulsing treatment, which accelerates the mobility of dislocations in the dynamic recrystallization process.
The present study was conducted to investigate the anti-inflammatory effect of vitamin D both in juvenile Jian carp (Cyprinus carpio var. Jian) in vivo and in enterocytes in vitro. In primary enterocytes, exposure to 10 mg lipopolysaccharide (LPS)/l increased lactate dehydrogenase activity in the culture medium (P<0·05) and resulted in a significant loss of cell viability (P<0·05). LPS exposure increased (P<0·05) the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6 and IL-8), which was decreased by pre-treatment with 1,25-dihydroxyvitamin D (1,25D3) in a dose-dependent manner (P<0·05). Further results showed that pre-treatment with 1,25D3 down-regulated Toll-like receptor 4 (TLR4), myeloid differentiation primary response gene 88 (Myd88) and NF-κB p65 mRNA expression (P<0·05), suggesting potential mechanisms against LPS-induced inflammatory response. In vivo, intraperitoneal injection of LPS significantly increased TNF-α, IL-1β, IL-6 and IL-8 mRNA expression in the intestine of carp (P<0·05). Pre-treatment of fish with vitamin D3 protected the fish intestine from the LPS-induced increase of TNF-α, IL-1β, IL-6 and IL-8 mainly by downregulating TLR4, Myd88 and NF-κB p65 mRNA expression (P<0·05). These observations suggest that vitamin D could inhibit LPS-induced inflammatory response in juvenile Jian carp in vivo and in enterocytes in vitro. The anti-inflammatory effect of vitamin D is mediated at least in part by TLR4-Myd88 signalling pathways in the intestine and enterocytes of juvenile Jian carp.
In this study, the authors have comparatively studied the influence of H2 addition on the structures and properties of ZnO films grown by metal organic (MO) chemical vapor deposition with dimethyl zinc and diethyl zinc as zinc precursors and N2O and O2 as oxygen sources, respectively. Various characterization methods, like x-ray diffraction, Raman scattering, Hall effect, photoluminescence, and atomic force microscopy, have been utilized, showing that H2 has different effects on different MO precursors and oxidants. The H2 addition has significantly improved the crystal structural quality of ZnO thin films for the case of dimethyl zinc source, but an opposite effect has been found for the case of diethyl zinc. Moreover, the H2 addition can significantly improve the optical properties of the ZnO films, regardless of the zinc MO sources used, with the surface morphology improved too. The suppression of carbon-related contaminations depends on the use of different precursors and whether H2 is added. By analyzing the experimental results, we have given the effects of H2 on the decomposition of the discussed MO precursors and oxidants, the proposed mechanism could be used in understanding the experimental data.
The etiology and pathogenesis of neurodegenerative disorders has yet to be elucidated, so their differential diagnosis is a challenge. This is especially true in differentiating Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson disease (PD), and multiple system atrophy (MSA).
A total of 11 eligible articles were identified by search of electronic databases including PubMed, Springer Link, Elsevier, and the Cochrane Library, up to June 2014. In meta-analyses, standardized mean differences (SMD), with 95% confidence intervals (CI), comparing cerebrospinal fluid (CSF) measures of α-synuclein between the above conditions were calculated using random-effects models.
CSF α-synuclein concentrations were significantly higher in AD compared to DLB [SMD: 0.32, 95% CI: (0.02, 0.62), z = 2.07, P = 0.038]; PD [SMD: 0.87, 95% CI: (0.15, 1.58), z = 2.38, P = 0.017]; or MSA [SMD: 1.14, 95% CI: (0.15, 2.14), z = 2.25, P = 0.025]. However, no significant difference was found between patients with AD and neurological cognitively normal controls [SMD: 0.02, 95% CI: (−0.21, 0.24), z = 0.13, P = 0.894].
Results of these meta-analysis suggest that quantification of CSF α-synuclein could help distinguish AD from other neurodegenerative disorders such as DLB, PD, or MSA.
The effect of high-energy electropulsing treatment (EPT) on the microstructure evolution, mechanical properties, and fracture behavior of as-treated Ti–6Al–4V alloy strips was investigated. EPT was found to accelerate phase transition and microstructure evolution of quasi-single-phase titanium alloy strips at a relatively low temperature, and obtain characteristic duplex microstructure and Widmanstatten microstructure. The EPT-induced microstructural changes increased elongation-to-failure remarkably with a slight decrease in tensile strength. Fracture surface observation and three-dimensional analysis showed that transition from small-shallow dimple colony to big-deep colony fracture took place with an increase in frequency of EPT. The rapid phase change of the Ti–6Al–4V alloy strip under EPT was attributed to the enhancement of nucleation rate and atomic diffusion resulting from the coupling of the thermal and athermal effects. It is supposed that EPT can provide a highly efficient method for the intermediate-softening annealing of titanium alloy sheet/strips.
Electropulsing treatment (EPT) provided a promising technology to improve the microstructure and plasticity of the cold-rolled Ti–6Al–4V noticeably while only affecting the strength mildly. Thus, titanium alloy of high plasticity and good comprehensive property can be obtained by this high efficient processing method. The research found that the tensile ductility could be improved largely with the increasing frequency. In the low frequency, the maximum ductility (32.5%) could be obtained at 293 Hz-EPT. Under high-frequency EPT, plasticity has a slight decrease but the tensile strength increases in the contrary. With the help of multi-characterization, abstracting phenomena are explained and therefore the conclusion has been drawn that the whole process of increasing frequency EPT can be divided roughly into two periods: (a) recrystallization period in the low frequency, at this period athermal effect of the EPT played a leading role and (b) phase change period in the high frequency, at this period the other important factor of the EPT thermal effect was predominant. As a comparison, furnace heat treatment is conducted to prove the preferential phase transition instead of complete recrystallization under the single heating effect. The mechanism of the results can be discussed by the competitive mechanism of recrystallization process and phase change in the EPT processing.
In this paper, we study the existence of infinitely many periodic solutions for the non-autonomous second-order Hamiltonian systems with symmetry. Based on the minimax methods in critical point theory, in particular, the fountain theorem of Bartsch and the symmetric mountain pass lemma due to Kajikiya, we obtain the existence results for both the superquadratic case and the subquadratic case, which unify and sharply improve some recent results in the literature.
Fine-sized powders of BaSi3Al3O4N5:Eu2+ phosphors with high stability and improved photoluminescence properties were successfully synthesized by the traditional solid-state reaction method under a reductive atmosphere using BaF2-fluxing additives in the raw powder mixture. The produced phosphors had strong blue emission under excitation in ultraviolet (UV) and vacuum ultraviolet (VUV) light, due to the 4f 5d–4f7 transition of Eu2+ ions. X-ray diffraction, scanning electron microscopy, XANES, and the photoluminescence (PL) spectra under UV and VUV were used to characterize the as-received samples. The experimental results showed that the addition of BaF2 flux improved the crystalline regime and the PL properties of the produced phosphors. Most significantly, it allowed control of the particle size and particle size distribution in the final powders but did not jeopardize the high thermal and chemical stability of the phosphors produced. With the modification of the BaF2 flux, the blue-emitting BaSi3Al3O4N5:Eu2+ phosphors will show excellent packing and coating properties and could be a good candidate for the light-emitting diodes and plasma display panels.