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Rational construction of Z-scheme photocatalysts and exploration of the Z-scheme charge transfer mechanism have drawn much attention in the field of CO2 reduction because of its great potential to alleviate energy crisis and environmental problems. In this study, a series of Z-scheme CdS/BiOI composites were constructed by depositing CdS nanoparticles on the surface of BiOI nanosheets. The synthesized materials were characterized comprehensively, and their photoreduction CO2 activities were evaluated. The results show that the composites exhibit higher photoreduction CO2 activity under visible light irradiation (λ > 400 nm) than pure CdS and BiOI. The yields of CO and CH4 for the optimal composite after 3 h irradiation are 3.32 and 0.54 μmol/g, respectively. The improved photocatalytic activity is attributed to Z-scheme transfer mode of the photogenerated charges in the composites. The mechanism of CO2 reduction is proposed and verified experimentally.
Light-absorbing impurities (LAIs, e.g. black carbon (BC), organic carbon (OC), mineral dust (MD)) deposited on snow cover reduce albedo and accelerate its melting. Northern Xinjiang (NX) is an arid and semi-arid inland region, where snowmelt leads to frequent floods that have been a serious threat to local ecological security. There is still a lack of quantitative assessments of the effects of LAIs on snowmelt in the region. This study investigates spatial variations of LAIs in snow and its effect on snow albedo, radiative forcing (RF) and snowmelt across NX. Results showed that concentrations of BC, OC (only water-insoluble OC), MD ranged from 32 to 8841 ng g−1, 77 to 8568 ng g−1 and 0.46 to 236 µg g−1, respectively. Weather Research and Forecasting Chemistry model suggested that residential emission was the largest source of BC. Snow, Ice, and Aerosol Radiative modelling showed that the average contribution of BC and MD to snow albedo reduction was 17 and 3%, respectively. RF caused by BC significantly exceeded RF caused by MD. In different scenarios, changes in snow cover duration (SCD) caused by BC and MD decreased by 1.36 ± 0.61 to 6.12 ± 3.38 d. Compared with MD, BC was the main dominant factor in reducing snow albedo and SCD across NX.
The purpose of this paper is to establish some limit theorems of delayed averages for countable nonhomogeneous Markov chains. The definition of the generalized C-strong ergodicity and the generalized uniformly C-strong ergodicity for countable nonhomogeneous Markov chains is introduced first. Then a theorem about the generalized C-strong ergodicity and the generalized uniformly C-strong ergodicity for the nonhomogeneous Markov chains is established, and its applications to the information theory are given. Finally, the strong law of large numbers of delayed averages of bivariate functions for countable nonhomogeneous Markov chains is proved.
Echinococcus granulosus sensu stricto (s.s.), Echinococcus multilocularis and Echinococcus canadensis are the common causes of human echinococcosis in China. An accurate species identification tool for human echinococcosis is needed as the treatments and prognosis are different among species. The present work demonstrates a method for the simultaneous detection of these three Echinococcus species based on multiplex polymerase chain reaction (mPCR). Specific primers of this mPCR were designed based on the mitochondrial genes and determined by extensive tests. The method can successfully detect either separated or mixed target species, and generate expected amplicons of distinct size for each species. Sensitivity of the method was tested by serially diluted DNA, showing a detection threshold as less as 0.32 pg for both E. granulosus s.s. and E. canadensis, and 1.6 pg for E. multilocularis. Specificity assessed against 18 other parasites was found to be 100% except weakly cross-react with E. shiquicus. The assay was additionally applied to 69 echinococcosis patients and 38 healthy persons, confirming the high reliability of the method. Thus, the mPCR described here has high application potential for clinical identification purposes, and can further provide a useful tool for evaluation of serology and imaging method.
This study aimed to determine whether increased carotenoids intake was associated with reduced risk of gestational diabetes mellitus (GDM). We performed a cross-sectional analysis using data from Tongji Maternal and Child Health Cohort study. The dietary carotenoids intake of 1978 pregnant women was assessed using a researcher-administered FFQ before undertaking an oral glucose tolerance test at 24–28 weeks. Multivariate logistic and linear regression analyses were used to obtain the effect estimates. Participants in the highest quartile of lycopene intake showed a lower risk of GDM (OR 0·50; 95 % CI 0·29, 0·86; Pfor trend = 0·007) compared with those in the lowest quartile; each 1 mg increase in lycopene consumption was associated with a 5 % (95 % CI 0·91, 0·99; Pfor trend = 0·020) decrease in GDM risk. No significant association was found between α-carotene, β-carotene, β-cryptoxanthin, lutein/zeaxanthin intake and GDM risk. Multiple linear regression analysis suggested an inverse association between lycopene intake and fasting blood glucose (FBG) (Pfor trend < 0·001); each 1 mg increase in lycopene intake was associated with 0·005 (95 % CI 0·002, 0·007; Pfor trend < 0·001) mmol/l decrease in FBG. Interaction analysis indicated consistent effect on each age or pre-BMI subgroup; however, a stronger protective effect of lycopene intake against GDM was observed among primigravid women (OR 0·20; 95 % CI 0·07, 0·55 in the highest v. the lowest quartile of intake; Pfor interaction = 0·036). In conclusion, dietary lycopene intake was mainly assumed via reducing FBG to decrease GDM risk, and the protection was relatively increased among primigravid women.
The plerocercoid (sparganum) of Spirometra erinaceieuropaei is the main aetiological agent of human sparganosis. To improve the current knowledge on S. erinaceieuropaei evolution, we performed multi-locus microsatellite typing of sparganum isolates from China for the first time. All available expressed sequence tag (EST) sequences for the Spirometra were downloaded from the GenBank. The identification and localization of microsatellites in ESTs was accomplished by MISA. Based on the selected microsatellites, the genetic structure of 64 sparganum isolates collected from 11 geographical locations in southwest China were investigated through principal component analysis, STRUCTURE analysis and neighbour-joining clustering. A total of 522 non-redundant ESTs containing 915 simple sequence repeats were identified from 12 481 ESTs screened. Five primer pairs were finally selected. Using these loci, a total of 12 alleles were detected in 64 sparganum isolates. Little variability was observed within each of geographical population, especially among isolates derived from Kunming of Yunnan (YN-KM) province. Both STRUCTURE analysis and the clustering analysis supported that two genotypes existed among the sparganum isolates from southwest China. In conclusion, five microsatellite markers were successfully developed, and sparganum population was observed to harbour low genetic variation, further investigation with deeper sampling was needed to elucidate the population structure.
La3+ doped yttrium iron garnet films have been grown on (111) oriented gadolinium gallium garnet substrates via Liquid phase epitaxy technique as a basic material for ISHE device fabrication. Pt as a material with a large spin hall angle was used as a spin detection layer. We investigated the dependence of the spin pumping effect on the power and frequency of the excitation microwaves in La:YIG/Pt bilayers by measuring the ISHE voltage. We demonstrated that the area under the ISHE curve(SISHE) across a wide power range had a nearly linear correlation with the input microwave power (Pin). The parameter SISHE can be used to describe the spin current energy in a Pt layer which can be a useful parameter for a microwave rectifier.
Optoelectronic nanoscale devices have wide applications in chemical, biological, and medical technologies. Improving the performance efficiency of these devices remains a challenge. Performance is mainly dictated by the structure and characteristics of the semiconductor materials. Once a nanodevice is fabricated, its efficiency is determined. The key to improving efficiency is to control the interfaces in the device. In this article, we describe how the piezo-phototronic effect can be effectively utilized to modulate the band at the interface of a metal/semiconductor contact or a p–n junction to enhance the external efficiency of many optoelectronic nanoscale devices such as photodetectors, solar cells, and light-emitting diodes (LEDs). The piezo-phototronic effect can be highly effective at enhancing the efficiency of energy conversion in today’s green and renewable energy technology without using the sophisticated nanofabrication procedures that have high cost and complexity.
Maternal dietary patterns and macronutrients intake have been shown to affect the development of gestational diabetes mellitus (GDM), but the findings are inconsistent. We aimed to identify maternal dietary patterns and examine their associations with GDM risk, and to evaluate the contributions of macronutrients intake to these associations. We included 2755 Chinese pregnant women from the Tongji Maternal and Child Health Cohort. Dietary intakes were assessed using a validated semi-quantitative FFQ 2 weeks before the diagnosis of GDM. GDM (n 248) was diagnosed based on the results of a 75-g, 2-h oral glucose tolerance test at 24–28 weeks gestation. We derived five different dietary patterns from a principal component analysis. The results showed that high fish–meat–eggs scores, which were positively related to protein intake and inversely related to carbohydrate intake, were associated with a higher risk of GDM (adjusted OR for quartile 4 v. quartile 1: 1·83; 95 % CI 1·21, 2·79; Ptrend=0·007) and higher plasma glucose levels. In contrast, high rice–wheat–fruits scores, which were positively related to carbohydrate intake and inversely related to protein intake, were associated with lower risk of GDM (adjusted OR for quartile 3 v. quartile 1: 0·54; 95 % CI 0·36, 0·83; Ptrend=0·010) and lower plasma glucose levels. In addition, dietary protein and carbohydrate intake significantly contributed to the associations between dietary patterns and GDM risk or glucose levels. These findings suggest that a dietary pattern characterised by high protein and low carbohydrate intake in pregnancy was associated with a higher risk of GDM, which may provide important clues for dietary guidance during pregnancy to prevent GDM.
The growth advantage of twinned dendrites over regular columnar ones was systematically investigated during Bridgman solidification. An experimental approach was designed and the results indicated that the strong twin growth advantage lost its efficiency in the coexisting microstructure containing both twinned and regular dendrites at a low growth rate of 10 μm/s. The twin growth advantage derives from three essential components: the lateral twin propagation perpendicular to twin plane (Rx), the propagation parallel to twin plane (Ry), and the dendrite tip growth (Rz). The lateral extension component Rx played a vital role and would be limited at a low rate. Meanwhile, the tip undercooling of the twinned dendrite was estimated based on its plate-like growth morphology. Furthermore, the competitive growth between twinned dendrites was investigated in different feathery grains. When the included angle between twin planes was relatively large, the lateral twin propagation would keep down the in-plane twin propagation.
Two new species of egg parasitoids, Oobius saimaensis Yao and Mottern new species and Oobius fleischeri Yao and Duan new species (Hymenoptera: Encyrtidae), are described from eggs of Agrilus fleischeri Obenberger, 1925 (Coleoptera: Buprestidae). Agrilus fleischeri is a phloem-feeding woodborer of poplar (Populus Linnaeus; Salicaceae) in northeastern China. These two species can be distinguished morphologically as O. fleischeri has five tarsomeres and O. saimaensis has four tarsomeres. Although O. saimaensis is morphologically similar to its sympatric congener O. agrili Zhang and Hang, 2005, an important natural enemy of the invasive emerald ash borer, Agrilus planipennis Fairmaire, 1888, molecular phylogenetics and morphological data indicate that they are distinct species. Phylogenetic relationships among the new species and other closely related species are also inferred by using DNA sequence data from several ribosomal and mitochondrial genes. In addition, we expand the known distribution of Oobius primorskyensis Yao and Duan, 2016 to include South Korea.
A novel wideband circularly polarized printed antenna is proposed in this paper. It consists of asymmetrical ground and monofilar spiral stubs connecting to it. By employing an inverted L-shaped microstrip feedline to excite the slit etched in the ground and spiral stubs, a wideband culalry polarized performance of the proposed antenna is realized. After optimization, the measured results of the final structure demonstrate that a 10 dB bandwidth of 76.2% from 2.6 to 5.8 GHz and a 3 dB axial-ratio bandwidth for circular polarization of 72.9% from 2.7 to 5.8 GHz could be achieved which could completely cover the Wimax (3.3–3.8 GHz) band.
For the first time, an experiment has been conducted to investigate synthetic jet laminar vortex rings impinging onto porous walls with different geometries by time-resolved particle image velocimetry. The geometry of the porous wall is changed by varying the hole diameter on the wall (from 1.0 mm to 3.0 mm) when surface porosity is kept constant (
). The finite-time Lyapunov exponent and phase-averaged vorticity field derived from particle image velocimetry data are presented to reveal the evolution of the vortical structures. A mechanism associated with vorticity cancellation is proposed to explain the formation of downstream transmitted vortex rings; and both the vortex ring trajectory and the time-mean flow feature are compared between different cases. It is found that the hole diameter significantly influences the evolution of the flow structures on both the upstream and downstream sides of the porous wall. In particular, for a porous wall with a small hole diameter (
, 0.10 and 0.133), the transmitted finger-type jets will reorganize into a well-formed transmitted vortex ring in the downstream flow. However, for the case of a large hole diameter of
, the transmitted vortex ring is not well formed because of insufficient vorticity cancellation. Additionally, the residual vorticity gradually evolves into discrete jet-like structures downstream, which further weaken the intensity of the transmitted vortex ring. Consequently, the transmitted flow structures for the
case would lose coherence more easily (or probably even transition to turbulence), resulting in a faster decay of the axial velocity and stronger entrainment of the transmitted jet. For all porous wall cases, the velocity profile of the transmitted jet exhibits self-similar behaviour in the far field (
), which agrees well with the velocity distribution of free synthetic jets. With the help of the control-volume approach, the time-mean drag of the porous wall is evaluated experimentally for the first time. It is shown that the porous wall drag increases with the decrease in the hole diameter. Moreover, for a porous wall with a small hole diameter (
, 0.10 and 0.133), it appears that the porous wall drag mainly derives from the viscous effect. However, as
increases to 0.20, the form drag associated with the porous wall geometry becomes significant.
Previously, the concept of Ply Drop Sequence (PDS) is introduced by the authors for the designing of composite laminated structures with multiple regions. Compared to deleting a contiguous innermost/outermost plies in the classical guide-based blending, using PDS is more flexible than dropping plies between adjacent regions. In this article, a new blending model called the Permutation for Panel Sequence (PPS) blending model is proposed to correct the problem of repeated searching of discrete points in the design space for the previous PDS blending model. The proposed method is also applied to an 18-panel horseshoe benchmark problem. The results demonstrate that the useful searching points in the PPS method are less than those in the PDS method when the number of the panels is less than the number of plies in the guide laminate, and the PPS method obtains a faster convergence speed compared with the PDS method.
Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in a laser system, which can also serve as a reference in certain applications. The authors prove that all of the beam transfer information (position and pointing) can theoretically be monitored and recorded by the sensor. Furthermore, auto-alignment with a single lens sensor is demonstrated on a simple beam line, and the results indicate that effective auto-alignment is achieved.
Background: Parkinson’s disease (PD) is a degenerative disorder of the central nervous system mainly affecting the motor system. Presently, there is no effective and safe drug to treat patients with PD. Ginkgo biloba extract (GBE), obtained from leaves of the Ginkgo biloba tree, is a complex mixture of ingredients primarily containing two active components: flavonoids and terpenoids. In this study, we investigated the effects of GBE on A53T α-synuclein transgenic mice, a PD model that has better simulated the progression of PD patients than other models such as the 1-methyl-4-phenyl-1,2,3,6 tetrahydropyridine–induced PD model. Methods: Fifty α-synuclein A53T transgenic mice were fed and treated with GBE, and locomotor activity was detected by pole test, forced swim test, and wire-hang test. The expression of tyrosine hydroxylase and dopamine transporters was detected using immunohistochemistry. Superoxide dismutase activity, glutathione peroxidase activity, and malondialdehyde expression were detected using an assay kit. Results: Our results show that GBE treatment improved locomotor activity and that superoxide dismutase and glutathione peroxidase inhibited the expression of methane dicarboxylic aldehyde and recovered the expression of tyrosine hydroxylase and dopamine transporters. Conclusions: The GBE treatment improved locomotor activity and inhibited the development of PD in the A53T α-synuclein transgenic mice, which may be partly responsible for decreased oxidative damage and maintain the normal dopamine homeostasis.
Little is known about the combined use of benzodiazepines and antidepressants in older psychiatric patients. This study examined the prescription pattern of concurrent benzodiazepines in older adults treated with antidepressants in Asia, and explored its demographic and clinical correlates.
The data of 955 older adults with any type of psychiatric disorders were extracted from the database of the Research on Asian Psychotropic Prescription Patterns for Antidepressants (REAP-AD) project. Demographic and clinical characteristics were recorded using a standardized protocol and data collection procedure. Both univariate and multiple logistic regression analyses were performed.
The proportion of benzodiazepine and antidepressant combination in this cohort was 44.3%. Multiple logistic regression analysis revealed that higher doses of antidepressants, younger age (<65 years), inpatients, public hospital, major comorbid medical conditions, antidepressant types, and country/territory were significantly associated with more frequent co-prescription of benzodiazepines and antidepressants.
Nearly, half of the older adults treated with antidepressants in Asia are prescribed concurrent benzodiazepines. Given the potentially adverse effects of benzodiazepines, the rationale of benzodiazepines and antidepressants co-prescription needs to be revisited.
In this paper we investigate the Parisian ruin problem of the general dual Lévy risk model. Unlike the usual concept of ultimate ruin, allowing the surplus level to be negative within a prespecified period indicates that the deficit at Parisian ruin is not necessarily equal to zero. Hence, we consider a Gerber–Shiu type expected discounted penalty function at the Parisian ruin and obtain an explicit expression for this function under the dual Lévy risk model. As particular cases, we calculate the Parisian ruin probability and the expected discounted kth moments of the deficit at the Parisian ruin for the compound Poisson dual risk model and a drift-diffusion model. Numerical examples are given to illustrate the behavior of Parisian ruin and the expected discounted deficit at Parisian ruin.
The Wuhan Pre/Post-Natal Twin Birth Registry (WPTBR) is one of the largest twin birth registries with comprehensive medical information in China. It recruits women from the first trimester of pregnancy and their twins from birth. From January 2006 to May 2016, the total number of twins enrolled in WPTBR is 13,869 twin pairs (27,553 individuals). The WPTBR initiated the Wuhan Twin Birth Cohort (WTBC). The WTBC is a prospective cohort study carried out through incorporation of three samples. The first one comprises 6,920 twin pairs, and the second one, 6,949 twin pairs. Both are population-based samples linked to the WPTBR and include pre- and post-natal information from WPTBR. The second sample includes neonatal blood spots as well. Using a hospital-based approach, we recently developed a third sample with a target enrolment of 1,000 twin pairs and their mothers. These twins are invited, via their parents, to participate in a periodic health examination from the first trimester of pregnancy to 18 years. Biological samples are collected initially from the mother, including blood, urine, cord blood, cord, amniotic fluid, placenta, breast milk and meconium, and vaginal secretions, and later from the twins, including meconium, stool, urine, and blood. This article describes the design, recruitment, follow-up, data collection, and measures, as well as ongoing and planned analyses at the WTBC. The WTBC offers a unique opportunity to follow women from prenatal to postnatal, as well as follow-up of their twins. This cohort study will expand the understanding of genetic and environmental influences on pregnancy and twins’ development in China.