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Bipolar disorder is a highly heritable polygenic disorder. Recent
enrichment analyses suggest that there may be true risk variants for
bipolar disorder in the expression quantitative trait loci (eQTL) in the
We sought to assess the impact of eQTL variants on bipolar disorder risk
by combining data from both bipolar disorder genome-wide association
studies (GWAS) and brain eQTL.
To detect single nucleotide polymorphisms (SNPs) that influence
expression levels of genes associated with bipolar disorder, we jointly
analysed data from a bipolar disorder GWAS (7481 cases and 9250 controls)
and a genome-wide brain (cortical) eQTL (193 healthy controls) using a
Bayesian statistical method, with independent follow-up replications. The
identified risk SNP was then further tested for association with
hippocampal volume (n = 5775) and cognitive performance
(n = 342) among healthy individuals.
Integrative analysis revealed a significant association between a brain
eQTL rs6088662 on chromosome 20q11.22 and bipolar disorder (log Bayes
factor = 5.48; bipolar disorder P =
5.85×10–5). Follow-up studies across multiple independent
samples confirmed the association of the risk SNP (rs6088662) with gene
expression and bipolar disorder susceptibility (P =
3.54×10–8). Further exploratory analysis revealed that
rs6088662 is also associated with hippocampal volume and cognitive
performance in healthy individuals.
Our findings suggest that 20q11.22 is likely a risk region for bipolar
disorder; they also highlight the informative value of integrating
functional annotation of genetic variants for gene expression in
advancing our understanding of the biological basis underlying complex
disorders, such as bipolar disorder.
The need for higher energy density batteries has spawned recent renewed interest in alternatives to lithium ion batteries, including multivalent chemistries that theoretically can provide twice the volumetric capacity if two electrons can be transferred per intercalating ion. Initial investigations of these chemistries have been limited to date by the lack of understanding of the compatibility between intercalation electrode materials, electrolytes, and current collectors. This work describes the utilization of hybrid cells to evaluate multivalent cathodes, consisting of high surface area carbon anodes and multivalent nonaqueous electrolytes that are compatible with oxide intercalation electrodes. In particular, electrolyte and current collector compatibility was investigated, and it was found that the carbon and active material play an important role in determining the compatibility of PF6-based multivalent electrolytes with carbon-based current collectors. Through the exploration of electrolytes that are compatible with the cathode, new cell chemistries and configurations can be developed, including a magnesium-ion battery with two intercalation host electrodes, which may expand the known Mg-based systems beyond the present state of the art sulfide-based cathodes with organohalide-magnesium based electrolytes.
To conduct a meta-analysis to compare the short-term outcomes of robotic thyroidectomy and conventional open thyroidectomy for differentiated thyroid cancer.
Medline, Embase, Science Citation Index Expanded and the Cochrane Library databases were searched for relevant literature. The evaluated endpoints were intra-operative and post-operative outcomes.
Twelve eligible, non-randomised comparative studies involving 2513 patients were included, with 923 patients in the robotic thyroidectomy group and 1590 patients in the conventional open thyroidectomy group. Meta-analysis results revealed that robotic thyroidectomy was associated with significantly longer operative time and a lower number of retrieved central lymph nodes, as compared with conventional open thyroidectomy. No significant differences were found between robotic thyroidectomy and conventional open thyroidectomy in terms of post-operative outcomes.
Robotic thyroidectomy appears to be a feasible and safe surgical procedure for patients with differentiated thyroid cancer. However, more high-quality randomised clinical trials should be undertaken to confirm these findings.
Two-step growth method of low pressure chemical vapor deposition(LPCVD) process was employed to fabricate the ZnO:B-TCO film; For the first layer, the seed layer with a heavy doping concentration was deposited on the glass substrate, the film having higher deposition rate were then grown on the top of the first layer; It shows that the doping situations of the seed layer play an important role in electrical and optical performance of the whole ZnO:B-TCO layer, and the combination of this two properties is optimal when the doping ratio (B2H6/DEZ) was 0.4;
Flexible electronics and microsystems are an emerging technology with a tremedous impact to the future electronics and information technology and widespread applications. Various devices and microsystems have been developed. Surface acoustic wave (SAW) devices are a type of essential device for electronics, microsensors and microsystems; however there is no activity on the development of flexible SAW devices yet. This paper reports the development of flexible SAW devices on cheap, bendable and disposable plastic films. Flexible SAW devices with resonant frequency of 198.1 MHz and 447 MHz for the Rayleigh and Lamb waves respectively have been obtained with a large transmission signal up to 18dB. The flexible SAW devices have also demonstrated their ability for acoustic streaming with a velocity up to 3.4 cm/s and for particle concentration. The results have clearly demonstrated that the flexible SAW devices have great potential for applications in electronics and microsystems.
We investigate the electronic structure of interstitial Li and Li vacancy in Li7P3S11 by first principles calculations. We find that Li7P3S11 is a good insulator with a wide band gap of 3.5 eV. We find that the Li vacancy and interstitial Li+ ion do not introduce states in the band gap hence they do not deteriorate the electronic properties of Li7P3S11. The calculated formation energies of Li vacancies are much larger than those of Li interstitials, indicating that the ion conductivity may arise from the migration of interstitial Li.
We investigate the impact of various dopants (Na, Ag, Cd, Zn, Al, Ga, In, Tl, Ge, and Sn) on the electronic structure of Mg2Si by first principles calculations using a hybrid functional that does not need a band gap correction. We find that for Na and Ge in Mg2Si, the impurity-induced states do not affect the density of states at both edges of the valence band and the conduction band. Ag- and Sn affect slightly the density of states at the valence band edge, while Cd and Zn affect slightly the density of state at the conduction band edge. Al and In could modify significantly the density of states at the conduction band edge. Ga introduces states just at the bottom of the conduction band. Tl introduces states in the band gap. This study provides useful information on optimizing the thermoelectric efficiency of Mg2Si.
Defect energy levels of oxygen vacancies in various high K oxides HfO2, ZrO2, La2O3 and SrTiO3 have been calculated using methods which give the correct band gap, such as the screened exchange and weighted density approximation.
Epitaxial growth of the dilute magnetic semiconductors GaMnP and GaMnN has been investigated by Gas Source Molecular Beam Epitaxy (GSMBE). GaMnP films grown with < 4.5% Mn show the preferential formation of the second phases MnP and Mn5.64P3, resulting in only a slight deviation from purely diamagnetic behavior. GaMnN films grown on both Al2O3 and Metal-Organic Chemical Vapor Deposition (MOCVD) derived GaN surfaces show strong ferromagnetism when grown with either C codoping or at elevated temperatures to raise the concentration of n-type carriers. Comparable GaMnN films grown under conditions which produce highly resistive material show only paramagnetism, indicating the importance of carrier concentration on the resulting magnetic behavior. The formation of second phases was not observed in the GaMnN material for Mn concentrations less than 9%.
Zirconia-yttria films containing 8.0wt% Y2O3 were prepared on a Si substrate with r.f. magnetron sputtering deposition followed by 170 KeV Ar+ ion irradiation at room temperature. The characterization of these zirconia-yttria films with different ion bombarding doses has been studied by XRD, XPS and AES. It was found that all the films consisted of three portions, the amorphous films deposited with r.f. magnetron-sputtering were partially crystallized and nontransformable tetragonal (T') phase was detected after Ar+ ion bombardment of a dose of 1×1016 ion/cm2, and the oxidized states of Zr3d, Y3d and Ols peaks of XPS were observed under the conditions of argon ion bombardment of different doses.
A systematic study of superconducting Te, Hc and also the behavior of resistivity of Nb/Si mfltiiayers is reported. Nb and Si layers with different thicknesses were deposited alternatively in an LUIV two electron—beam evaporating installation and controlled automatically by a microcomputerquartz—monitor system. Well reproduciole results were achieved. Structural analyses show very good modulated structure with (110)textured polycrystallino Nb and] amorphous Si layers. Superconducting Tc of Nb/Simultilayers are significantly higher than that of the sputtered Nb/Ge system. Thevariation of Hc(T) in parallel field manifests a 2D–3D crossover with transformation temperature of 0.7– 0.8 Tc. The possible mechanism and implication of these phenomena were discussed.
Crystalline films of Ge have been homoepitaxially grown through a liquid Au medium by the so-called vapor-liquid-solid (VLS) mechanism at relatively low temperature (400-450 °C). During the process, the Ge vapor is delivered by a molecular beam evaporator and the liquid phase in the system is formed at the interface by heating a Au metal film above its eutectic point with the semiconductor. This process has a potential of a high growth rate at low temperature. The growth process and the crystallinity of the films were monitored in situ by high energy ion backscattering and channeling. The surface morphology and quality of the films were examined by scanning electron microscopy and cross-sectional transmission electron microscopy. The experimental results are presented, together with a discussion of the growth mechanism and the nature of the liquid metal-semiconductor interface.
Thin SiO2 films grown on silicon substrates were exposed to electron beam irradiation at energies from 100 eV to 2.5 KeV. Then, thermally stimulated exoelectron emission (TSEE) spectra were taken by heating the sample linearly to a maximum temperature of 600°C. We have compared the emission behavior from oxides grown on both n-typeand p-type, (100) and (111) silicon wafers. The TSEE spectra show emission peaks whichcan be categorized by their behavior into two groups. The β emission peaks are characteristic of emission from localized electron traps while the γ emission peaks result from the annealing of beam-induced defects. We have observed changes in the β peaks which appear to be associated with the concentration of dopants in the substrate material. In addition, we have identified a beam energy threshold near the oxygen Is binding energy for the creation of defects. This suggests that defect creation results froman electronic transition similar to electron stimulated desorption.
Electron beam irradiation at energies between 0.5 and 4 keV has been found to produce defects in oxide materials including SiO2, Al2O3 and ZrO2. These defects trap excess charge in the materials and affect their electronic and optical properties. Measurements of the thermally stimulated exoelectron emission following irradiation provides information on relative defect concentrations, defect creation mechanisms, electron trap binding energies, electron emission mechanisms and annealing properties of these materials. Electron emission during sample heating occurs via a variety of mechanisms including the thermionic emission of excess charge from defects at temperatures characteristic of each trap binding energy. By measuring relative trap concentrations as a function of beam parameters, we have identified electron beam energy thresholds for the creation of some types of defects which correlate with core level electronic transitions. Also, electron emission which occurs during defect annealing or diffusion to a surface shows the conditions for the elimination of defects. The ability to control and characterize defect formation and annihilation provides the possibility of engineering specific surface defect conditions. In addition, defect creation by electronic processes is very selective as compared with momentum transfer in ion beam damage of surfaces.
Ionized cluster beam deposition (ICBD) technique has been used to deposit Ag films on both Si(111) and Si(100) substrates. Sizes of clusters in ionized cluster beam are found to distribute in a range of 100–600 atoms/cluster. X-ray diffraction (XRD), and α-step profile methods are used to analyze the properties of Ag films. As a comparison, Ag films deposited by conventional evaporation are also investigated. Highly textured Ag films with strong (111) orientation on Si (111) have been obtained at high accelerating voltage Va=4kV. The crystallinity and surface flatness of Ag films can be improved by ICBD at high accelerating voltages.
We have fabricated highly-orientated crystalline potassium titanyl phosphate (KTP) films on a variety of substrates by pulsed excimer laser ablation. The resulting films have been extensively characterized in terms of their compositional, crystalline, and optical properties. Nonlinear optical property of secondary harmonic generation of the films has been evaluated with a high d value comparable to that of KTP bulk crystals. The results are encouraging that the KTP films deposited are very promising for nonlinear optical waveguide device applications.