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Direct determination of barrier height (ΦBH) value between Ir and single crystal (001) hydrogen-terminated diamond with lightly boron doped has been performed using x-ray photoelectron spectroscopy technique. 70 nm Ir islands were formed on hydrogen-terminated diamond surface using anodic aluminum oxide. The ΦBH value for Ir/hydrogen-terminated diamond was −0.43 ± 0.14 eV, indicating that Ir was a suitable metal for ohmic contact with hydrogen-terminated diamond. The band diagram of Ir/hydrogen-terminated diamond was obtained. The experimental ΦBH was compared with the theoretical ΦBH in this work.
(1 − x)Ba(Mg1/3Ta2/3)O3–xBa(Co1/3Nb2/3)O3 (BMT–BCN, x = 0.0, 0.20, 0.25, 0.30, 0.40) ceramics were prepared using the traditional solid-state reaction method. X-ray diffraction patterns have shown that the intensities of (001) and (100) super-lattices decrease with the increase in the BCN content. Seven main Raman vibrational modes are observed, assigned, and illustrated, in particular. Raman shifts of Eg(O) modes and the FWHM values of F2g(O)/A1g(O) modes have close relationship with the dielectric properties. The calculated values by the four-parameter semiquantum model based on IR reflectivity match well with the measured data (@3.8 GHz), which means that most of dielectric contribution to the system may be ascribed to the absorption of structural phononic oscillations at the infrared region, and the contribution from the scattering of the defective phonons is small. The contributions of each vibrational mode on the dielectric responses were investigated in detail, indicating that the low-frequency modes (A2u(1) and Eu(1)) have a decisive role to the dielectric properties.
The crack initiation and early growth behaviors of a TC4 titanium alloy under high cycle fatigue and very high cycle fatigue were experimentally investigated. The results show that it exhibits the duplex S–N curve characteristics associated with surface and interior failures at a stress ratio of 0.1, while it represents the similar S–N curve characteristics only related to surface failure at a stress ratio of −1. The interior failure is accompanied with the occurrence of facets, granular bright facets (GBFs), and fisheye. Slip-like patterns are observable on the facets easily formed under positive stress ratio. The interior failure process is characterized as (i) occurrence of slip lines on partial α grains under cyclic loading, (ii) initiation and growth of microcracks within some α grains, (iii) coalescence of microcracks and formation of GBF, (iv) stable long crack growth within fisheye, (v) unstable crack growth outside fisheye, and (vi) final momentary fracture.
Lead is one of the environmental pollutants with cardiovascular toxicity. The embryos are particularly sensitive to lead exposure, because it can move through the blood-placental barrier and the blood-brain barrier easily during embryonic development. Cerebral cavernous malformations 3 (CCM3) gene plays an important role in cardiovascular development, mainly affecting cell proliferation, differentiation and apoptosis. In this study, we established a blood vessel development model of mouse embryos in order to imitate human people with CCM3 genes defects and exposing to environment toxin Pb in utero. We would like to determine the interaction of Pb and CCM3 gene on vascular development, and to explore the mechanisms. We found that the yolk sac of CCM3 heterozygous mice embryo showed abnormal morphology at E11.5 after lead treatment comparing with wild type (WT) mice without lead exposure, meanwhile it showed more angiogenesis and vascular remodeling in the hematoxylin and eosin stained sections of the CCM3+/− yolk sac with lead exposure. We also found that the similar effect of Pb and CCM3 gene on mitochondrial DNA (mtDNA) copy number in vivo and in vitro. Mitochondrial morphology and function also changed in primary human umbilical vein endothelial cells after lead exposure. Besides, it was found that the HIF-1α and TFAM which have close relationship with mtDNA biogenesis showed similarly increasing messenger RNA expression in both human and mouse-derived primary cells with lead treated and CCM3 gene knockout. All of the above results indicated that lead and CCM3 might damage endothelial cells through mitochondria pathway and eventually both affected angiogenesis.
In recent years, hand, foot, and mouth disease (HFMD) has been increasingly recognized as a critical challenge to disease control and prevention in China. Previous studies have found that meteorological factors such as mean temperature and relative humidity were associated with HFMD. However, little is known about whether the diurnal temperature range (DTR) has any impact on HFMD. This study aimed to quantify the impact of DTR on childhood HFMD in 18 cities in Sichuan Province. A distributed lag non-linear model was adopted to explore the temporal lagged association of daily temperature with age-, gender- and pathogen-specific HFMD. A total of 290 123 HFMD cases aged 0–14 years were reported in the 18 cities in Sichuan Province. The DTR–HFMD relationships were non-linear in all subgroups. Children aged 6–14 years and male children were more vulnerable to the temperature changes. Large DTR had the higher risk estimates of HFMD incidence in cases of EV71 infection, while small DTR had the higher risk estimates of HFMD incidence in cases of CV-A16 infection. Our study suggested that DTR played an important role in the transmission of HFMD with non-linear and delayed effects.
Outside surface fluctuations of inertial confinement fusion (ICF) capsule greatly affect the implosion performance. An atomic force microscope (AFM)-based profilometer is developed to precisely characterize the capsule surface with nanometer resolution. With the standard nine surface profiles and the complete coverage data, 1D and 2D power spectra are obtained to quantitatively qualify the capsule. Capsule center fast aligning, orbit traces automatic recording, 3D capsule orientation have been studied to improve the accuracy and efficiency of the profilometer.
Little is known about the joint mental health effects of air pollution and tobacco smoking in low- and middle-income countries.
To investigate the effects of exposure to ambient fine particulate matter pollution (PM2.5) and smoking and their combined (interactive) effects on depression.
Multilevel logistic regression analysis of baseline data of a prospective cohort study (n=41785). The 3-year average concentrations of PM2.5 were estimated using US National Aeronautics and Space Administration satellite data, and depression was diagnosed using a standardised questionnaire. Three-level logistic regression models were applied to examine the associations with depression.
The odds ratio (OR) for depression was 1.09 (95% CI 1.01–1.17) per 10 μg/m3 increase in ambient PM2.5, and the association remained after adjusting for potential confounding factors (adjusted OR = 1.10, 95% CI 1.02–1.19). Tobacco smoking (smoking status, frequency, duration and amount) was also significantly associated with depression. There appeared to be a synergistic interaction between ambient PM2.5 and smoking on depression in the additive model, but the interaction was not statistically significant in the multiplicative model.
Our study suggests that exposure to ambient PM2.5 may increase the risk of depression, and smoking may enhance this effect.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
The Honggong pluton is the largest ferroan alkalic (A-type) granite intrusion emplaced along the Jiangshan–Shaoxing fault zone in southwestern Zhejiang Province, and has important implications for understanding the Late Mesozoic tectonic evolution of SE China. U–Pb ages of 138.7 ± 0.8, 134.2 ± 1.1, 128.5 ± 1.5 and 126.1 ± 0.9 Ma were obtained from zircon by laser ablation–inductively coupled plasma–mass spectrometry, indicating that the Honggong pluton formed in the Early Cretaceous. The Honggong pluton has a clear ferroan alkalic (A-type) granite geochemical signature with, for example, high total alkali contents and FeOt/(FeOt + MgO) values. The Sr–Nd–Hf isotopic compositions suggest that there was juvenile material in the magma source. Geochemical evidence indicates that the pluton was derived through extensive fractionation of melts that contained both asthenospheric mantle and Mesoproterozoic crustal components. These rare granites in southern China were emplaced during five episodes at 235–225, 190, 165–155, 100–90 and 140–120 Ma. The age of the Honggong pluton suggests that localized extension in southwestern Zhejiang Province began as early as ~138 Ma and continued to 126 Ma. This Early Cretaceous extensional event was triggered by localized rollback of the subducting Pacific Plate.
In this paper, the recent studies of laboratory astrophysics with strong magnetic fields in China have been reviewed. On the Shenguang-II laser facility of the National Laboratory on High-Power Lasers and Physics, a laser-driven strong magnetic field up to 200 T has been achieved. The experiment was performed to model the interaction of solar wind with dayside magnetosphere. Also the low beta plasma magnetic reconnection (MR) has been studied. Theoretically, the model has been developed to deal with the atomic structures and processes in strong magnetic field. Also the study of shock wave generation in the magnetized counter-streaming plasmas is introduced.
Bulk nanocrystalline (NC) silvers were fabricated by spark plasma sintering process. The effects of sintering temperature on physical and mechanical properties of the NC silvers were investigated. The results indicate that no impurities were introduced into the bulk compacts during the preparation procedure. Both the density and the electrical conductivity of the NC Ag increase with an increase in sintering temperature. However, the micro-hardness and ultimate tensile strength (UTS) of the bulk compacts increase initially and then decrease with increasing sintering temperature. The NC Ag sintered at 500 °C exhibits the highest micro-hardness of 85.3 HV along with the best compression yield strength of 379 MPa and the highest UTS of 534 MPa. The deterioration of the mechanical properties of the NC Ag sintered at 550 °C should be attributed to the rapid grain growth.
The present study was performed to identify the genotype of a hypertrophic cardiomyopathy family and investigate the clinicopathogenic characteristics and prognostic features of relevant genetic abnormalities. Target sequence capture sequencing was performed to screen for pathogenic alleles in a 32-year-old female patient (proband). Sanger sequencing was carried out to verify the results. Sanger sequencing was also performed on other family members to identify allele carriers. A survival analysis was carried out using published literature and our findings. We found that the proband and her son harboured a Gly716Arg sequence variant of the β-myosin heavy chain. Neither the proband’s father nor the mother were carriers of this sequence variant; thus, the mutation was classified as “de novo”. Further survival analysis revealed that female patients appear to have a longer life expectancy compared with males. Our study may provide an effective approach for the genetic diagnosis of hypertrophic cardiomyopathy.
The microstructure evolution and mechanical properties of ultrafine-grained (UFG) Al sheets subjected to accumulative roll bonding (ARB) and subsequent cryorolling was studied. Cryorolling can suppress the dynamic softening of UFG Al sheets subjected to ARB at room temperature. After the third ARB pass, the grains are slightly refined as the number of ARB passes increases. However, the grains are significantly refined further during cryorolling. The grain size of 460 nm achieved after the third ARB pass is reduced to 290 nm after two cryorolling passes with total reduction ratio 80%. Sheets subjected to ARB + cryorolling show improved mechanical properties compared to only ARB-processed sheets due to a change in the fraction of high-angle boundaries and elongated grains. The deformation mechanism for ultrafine grains at room temperature is determined by grain boundary sliding or dislocation-based recovery, while it is governed by dislocation glide at cryogenic temperature.
A large schizophrenia genome-wide association study (GWAS) and a
subsequent extensive replication study of individuals of European
ancestry identified eight new loci with genome-wide significance and
suggested that the MIR137-mediated pathway plays a role
in the predisposition for schizophrenia.
To validate the above findings in a Han Chinese population.
We analysed the single nucleotide polymorphisms (SNPs) in the newly
identified schizophrenia candidate loci and predicted
MIR137 target genes based on our published Han
Chinese populations (BIOX) GWAS data. We then analysed 18 SNPs from the
candidate regions in an independent cohort that consisted of 3585
patients with schizophrenia and 5496 controls of Han Chinese
We replicated the associations of five markers
(P<0.05), including three that were located in the
predicted MIR137 target genes. Two loci
(ITIH3/4: rs2239547, P
=1.17×10–10 and CALN1: rs2944829,
P=9.97×10–9) exhibited genome-wide
significance in the Han Chinese population.
The ITIH3/4 locus has been reported to be of genome-wide
significance in the European population. The successful replication of
this finding in a different ethnic group provides stronger evidence for
the association between schizophrenia and ITIH3/4. We
detected the first genome-wide significant association of schizophrenia
with CALN1, which is a predicted target of
MIR137, and thus provide new evidence for the
associations between MIR137 targets and
Transistors in the traditional field effect geometry operate by the injection of mobile carriers – electrons or holes – from a source reservoir to the drain reservoir through a conducting channel region. The carriers enter the channel region by surmounting an electrostatic potential barrier. The gate electrode controls the height of this barrier capacitively. The carriers in the source reservoir are in thermal equilibrium with the source contact. This means that the carriers, say electrons, are distributed in energy in the conduction band according to the Fermi–Dirac distribution f(E = 1/1[1+exp((E − EF)/kT)]. The Maxwell–Boltzmann approximation f(E) ~ exp[− E/kT] of the Fermi–Dirac distribution for large energies represents the high-energy tail of the distribution. There are electrons in this tail with energy higher than the potential barrier; the gate cannot stop them from being injected into the channel. This leads to a sub-threshold “leakage” drain current ID ~ exp[qVGS / kT], which leads to the well-known sub-threshold slope (S) requirement of S ~ (kT / q)ln10 ~ 60 mV/dec change of current. Methods to make the SS steeper than the 300 K value of 60 mV/dec value are expected to substantially lower the power dissipation in digital logic and computation [1, 2]. The methods must explore novel mechanisms of charge transport, or of electrostatic gating. This chapter focuses on transport.
The high-energy tail of electrons exists because of the available density of states (DOS) DC(E) of the conduction band; the electron distribution in energy is n(E) = DC(E)f(E). If the DOS were cut off, there would be no tail, and it is possible to obtain S less than 60 mV/dec. This sort of energy filtering is possible if we replace the n-type source for electrons by a p-type source, which has a valence band maximum and zero DOS above. For injection into the channel of the n-FET, the electrons cannot undergo the traditional drift/diffusion process, but have to quantum mechanically tunnel through the bandgap. This energy-filtering scheme to achieve sub-60 mV/dec switching is the central idea behind the tunneling FET (or TFET).
Annual wild soybean characterized by low 100-seed weight (100SW), high protein content (PRC) and low oil content (OIC) may have favourable exotic genes/alleles for broadening the genetic base of the cultivated soybean. To evaluate the wild alleles/segments, a chromosome segment substitution line population comprising 151 lines with N24852 (wild) as the donor and NN1138-2 (cultivated) as the recurrent parent was analysed using single-marker analysis, interval mapping, inclusive composite interval mapping and mixed linear composite interval mapping. On 14 segments of ten chromosomes, 17 quantitative trait loci (QTL) were identified, with two segments each containing two QTL for 100SW and OIC and one segment containing two QTL for PRC and OIC, respectively. All the seven wild alleles/segments for 100SW were associated with negative effects and three were associated with positive effects, but one was associated with a negative effect for PRC, and five were associated with negative effects, but one was associated with a positive effect for OIC. Except Satt216 and Sat_224 for 100SW, the identified QTL/segments have been reported from cultivated soybean mapping populations. The detected wild segments may provide materials for further characterization, cloning and pyramiding of the alleles conferring the seed-quality traits.
Annual wild soybean characterized with more number of branches and pods may contain favourable exotic genes/alleles for improving the yield potential of cultivated soybeans. To evaluate the wild alleles/segments, the chromosome segment substitution line population SojaCSSLP3 comprising 158 lines with N24852 (wild) as the donor and NN1138-2 (cultivated) as the recurrent parent was tested under three environments. The phenotypic data along with 198 simple sequence repeat markers were analysed for qualitative trait loci (QTL)/segments associated with the number of branches on the main stem (BN) and number of pods per plant (PN) using the inclusive composite interval mapping procedure (RSTEP-LRT-ADD model) of ICIM version 3.0. The analysis was carried out for individual environments due to a significant G × E interaction. A total of eight QTL/segments associated with BN and eight QTL/segments associated with PN were detected under the three environments, with all the wild segments having positive effects. Among these, two QTL/segments for each of the two traits could be detected under two or three environments and three QTL/segments could be detected for both traits. Four QTL/segments associated with BN and one QTL/segment associated with PN were identified only in SojaCSSLP3, not reported for cultivated crosses in the literature. The detected wild segments may provide materials for further characterization, cloning and pyramiding of the alleles conferring the two traits.
Polycrystalline Ba8Ga16MgxGe30−x compounds were synthesized by combining solid-state reaction with spark plasma sintering (SPS) method. The structural and electronic properties of Mg-substituted Ge type-I clathrate phase Ba8Ga16MgxGe30−x (x = 1, 2, 3, 4) were investigated experimentally and theoretically. Theoretically structural and electronic properties of Ba8Ga16MgxGe30−x were calculated by first-principles method based on the density-functional theory. The results indicate a strong preference for the occupation of the 6c sites by Mg. It is found that Mg substitution for Ge can lower the melting points and bulk modulus of this system. The formation energies and the binding energies decrease with increasing Mg content, suggesting that the Mg-doped Ba8Ga16Ge30 clathrates are stable in a limited range of composition. The calculated results show that these alloys are all indirect gap semiconductors and the values of band gap increase with the increase of Mg content. All specimens exhibit the behavior of the p-type conduction, which is originated from the presence of a shallow acceptor energy level. The electrical conductivity and the room-temperature carrier mobility decrease with increasing Mg content, while the room-temperature carrier concentration increases with increasing Mg content.
Many countries are making increased efforts to improve marine security and safety and develop ship surveillance techniques to satisfy the increasing demands. Space-borne Synthetic Aperture Radar (SAR) delivers high performance day/night all weather capabilities and a space-based Automatic Identification System (AIS) can give near real time and global coverage. Limited by the development of sensors and data processing techniques, the integration of space-borne SAR and AIS has much to offer ship surveillance. State-of-the-art data fusion methods have generally provided satisfactory performance. However, in high-density shipping or high sea-states, performance quality is less assured. This paper firstly investigates improved data association methods. The association methods based on the position feature are improved, and multi-feature-based association methods are proposed. Then, ship identification and tracking by the integration of space-borne SAR and AIS are researched further. Multi-source data fusion strategy is also investigated. Finally, the discussion is presented and the future works are emphasized in the conclusion.
Ship surveillance is important for maritime security and safety. It plays important roles in many applications including ocean environment monitoring, search and rescue, anti-piracy and military reconnaissance. Among various sensors used for maritime surveillance, space-borne Synthetic Aperture Radar (SAR) is valued for its high resolution over wide swaths and all-weather working capabilities. However, the state-of-the-art algorithms for ship detection and identification do not always achieve a satisfactory performance. With the rapid development of space-borne Automatic Identification System (AIS), near real-time and global surveillance has become feasible. However, not all ships are equipped with or operate AIS. Space-borne SAR and AIS are considered to be complementary, and ship surveillance using an integrated combination has attracted much attention. In order to summarize the achievements and present references for further research, this paper attempts to explicitly review the developments in previous research as the basis of a brief introduction to space-borne SAR and AIS.