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Latrophilin (LPH) is known as an adhesion G-protein-coupled receptor which involved in multiple physiological processes in organisms. Previous studies showed that lph not only involved the susceptibility to anticholinesterase insecticides but also affected fecundity in Tribolium castaneum. However, its regulatory mechanisms in these biological processes are still not clear. Here, we identified two potential downstream carboxylesterase (cce) genes of Tclph, esterase4 and esterase6, and further characterized their interactions with Tclph. After treatment of T. castaneum larvae with carbofuran or dichlorvos insecticides, the transcript levels of Tcest4 and Tcest6 were significantly induced from 12 to 72 h. RNAi against Tcest4 or Tcest6 led to the higher mortality compared with the controls after the insecticides treatment, suggesting that these two genes play a vital role in detoxification of insecticides in T. castaneum. Furthermore, with insecticides exposure to Tclph knockdown beetles, the expression of Tcest4 was upregulated but Tcest6 was downregulated, indicating that beetles existed a compensatory response against the insecticides. Additionally, RNAi of Tcest6 resulted in 43% reductions in female egg laying and completely inhibited egg hatching, which showed the similar phenotype as that of Tclph knockdown. These results indicated that Tclph affected fecundity by positively regulating Tcest6 expression. Our findings will provide a new insight into the molecular mechanisms of Tclph involved in physiological functions in T. castaneum.
Astrophysical collisionless shocks are amazing phenomena in space and astrophysical plasmas, where supersonic flows generate electromagnetic fields through instabilities and particles can be accelerated to high energy cosmic rays. Until now, understanding these micro-processes is still a challenge despite rich astrophysical observation data have been obtained. Laboratory astrophysics, a new route to study the astrophysics, allows us to investigate them at similar extreme physical conditions in laboratory. Here we will review the recent progress of the collisionless shock experiments performed at SG-II laser facility in China. The evolution of the electrostatic shocks and Weibel-type/filamentation instabilities are observed. Inspired by the configurations of the counter-streaming plasma flows, we also carry out a novel plasma collider to generate energetic neutrons relevant to the astrophysical nuclear reactions.
We present laboratory measurement and theoretical analysis of silicon K-shell lines in plasmas produced by Shenguang II laser facility, and discuss the application of line ratios to diagnose the electron density and temperature of laser plasmas. Two types of shots were carried out to interpret silicon plasma spectra under two conditions, and the spectra from 6.6 Å to 6.85 Å were measured. The radiative-collisional code based on the flexible atomic code (RCF) is used to identify the lines, and it also well simulates the experimental spectra. Satellite lines, which are populated by dielectron capture and large radiative decay rate, influence the spectrum profile significantly. Because of the blending of lines, the traditional
value are not applicable in diagnosing electron temperature and density of plasma. We take the contribution of satellite lines into the calculation of line ratios of He-
lines, and discuss their relations with the electron temperature and density.
To track multiple ships and estimate the feature parameters of multiple emitters on board using electronic intelligence satellites under clutter interference, a long and random revisit time, and other complex conditions, a novel tracking algorithm using both kinematic (position and velocity) and feature information based on an improved Multiple Hypothesis Tracking (MHT) approach is proposed in this paper. Firstly, the characteristics of multi-ship tracking with multiple emitters using satellite electronic information are analysed, and a new model of an emitter is built as an extended target in geographical coordinates. Secondly, a pre-processing of measurements is utilised via hierarchical clustering using the location and feature information of emitters. Thirdly, feature information is incorporated into the MHT framework using Jensen-Shannon divergence distance and fuzzy C-means clustering to calculate track scores. Finally, we present the prediction and update of target states, especially the update of feature parameters, to realise joint kinematic and feature tracking of ships. The results of the simulation show that the proposed method has much better tracking performance than the standard MHT algorithm.
In this paper, a dual-wideband bandpass filter (BPF) with independently controllable center frequencies (CFs) and wide stopband suppression is presented using a new quintuple-mode resonator (QMR). By applying the classical odd-/even-mode analysis method, the resonant characteristics of the new QMR have been analyzed. It shows that five modes can be excited, and two of them can be employed to form the lower passband, while the other three modes contribute to the higher passband. For verification, a dual-wideband BPF using the new QMR is designed, fabricated, and tested. Experimental results show that the CFs of the dual-wideband BPF centered at 2.96 GHz and 5.695 GHz with 3 dB fractional bandwidths of 27.7 and 23.4%, respectively. In addition, 20-dB suppression in upper-stopband ranges from 2.23 to 4.04f0, where f0 is the center frequency of the first passband. The measurement results are in good agreement with the prediction results.
With the improvement of the bias instability of Micro-Electromechanical Systems (MEMS) gyroscopes, the g-sensitivity error is gradually becoming one of the more important factors that affects the dynamic accuracy of a MEMS gyroscope. Hence there is a need for correcting the g-sensitivity error. However, the traditional calibration of g-sensitivity error uses a centrifuge. The calibration conditions are harsh, the process is complex and the cost is relatively high. In this paper, a fast and simple method of g-sensitivity error calibration for MEMS gyroscopes is proposed. With respect to the bias and random noise of a MEMS gyroscope, the g-sensitivity error magnitude is relatively small and it is simultaneously coupled with the Earth's rotation rate. Therefore, in order to correct the g-sensitivity error, this work models the calibration for g-sensitivity error coefficients, designs an (8+N)-position calibration scheme, and then proposes a fitting method for g-sensitivity error coefficients based on the Newton iteration and least squares methods. Multi-group calibration experiments designed on a MEMS Inertial Measurement Unit (MEMS IMU) product demonstrate that the proposed method can calibrate g-sensitivity error coefficients and correct the g-sensitivity error effectively and simply.
Geochronological, elemental and isotopic data of the Dashizhuzi granites and lamprophyre dykes from the eastern Hebei – western Liaoning on the northern North China Craton (NCC) provide an insight into the nature of their magma sources and subcontinental lithospheric mantle. The Dashizhuzi granites have an emplacement age of 226 Ma. They have enriched lithospheric mantle type 1 (EM1-like) Sr–Nd isotopic compositions, and have distinctive features of high Na2O and Sr and low Y with high Sr/Y and (La/Yb)N ratios. These characteristics show that the Dashizhuzi granites originated directly from melting of mafic lower crust composed of pre-existing ancient crustal and enriched mantle-derived juvenile crustal materials at normal continental crustal depth of 33–40 km. The lamprophyre dykes are dated at 167 Ma, and can be divided into two groups. The Group 1 dykes have variable Sr–Nd isotopic compositions and mid-ocean-ridge basalt (MORB-) like Th/U, Ba/Th and Ce/Pb ratios, whereas the Group 2 dykes have enriched Sr–Nd isotopic compositions and notable high Co, Cr, MgO and low Al2O3 characteristics. These distinctive features suggest that the Group 1 dykes were derived from a relatively fertile lithospheric mantle source (garnet-facies amphibole-bearing lherzolite) which has experienced variable degrees of asthenospheric mantle-derived melt–peridotite interaction prior to melting. However, the Group 2 dykes were derived from an ancient garnet-facies phlogopite and/or amphibole-bearing lherzolite lithospheric mantle. Thinning of the Early Mesozoic lithospheric mantle beneath the northern NCC is dominantly through melt–peridotite interaction and thermo-mechanical erosion prior to Middle Jurassic time. The chemical compositions have been modified at the bottom of the lithospheric mantle through melt–peridotite interaction processes.
Fracture analysis is performed on a cylindrical composite consisting of an outer elastic layer, an inner rigid cylinder and an intermediate sliding interface. Interaction between the sliding interface and a parallel crack under in-plane shear is explored. An interesting phenomenon of oscillatory normal stress occurs on the local interfacial region near to the crack. It leads to local sliding-prevention and promotion effects, which constitute the mechanisms for the variations of stress intensity factors versus interfacial parameters. In addition, another interesting conclusion is that a crack near and parallel to a sliding interface never has the conventional anti-symmetry, even under pure in-plane shear loading.
Femtosecond laser direct writing (FsLDW) in transparent materials is a laser-based precise three-dimensional (3D) micro/nanofabrication method that has shown great potential for applications. The advantages of FsLDW originate in the nonlinear nature of absorption in the multiphoton absorption process. Over the past few years, transparent material micro/nanofabrication using FsLDW has seen several developments in materials and applications. Specifically, two-photon polymerization has been widely used as a precision direct-writing process for fabrication of polymeric 3D micro/nanostructures; internal/surface ablation of polymer 3D structures based on multiphoton absorption has been demonstrated and developed as a promising subtractive manufacturing technique; and femtosecond laser multiphoton modification in glass has been intensively studied for refractive-index change and generation of nanogratings and microvoids. This article describes the latest research on FsLDW in polymers and glasses with specific applications for large-dimension fabrication, microelectromechanical systems, microphotonics, and microfluidics.
Choline and betaine are essential nutrients involved in one-carbon metabolism and have been hypothesised to affect breast cancer risk. Functional polymorphisms in genes encoding choline-related one-carbon metabolism enzymes, including phosphatidylethanolamine N-methyltransferase (PEMT), choline dehydrogenase (CHDH) and betaine-homocysteine methyltransferase (BHMT), have important roles in choline metabolism and may thus interact with dietary choline and betaine intake to modify breast cancer risk. This study aimed to investigate the interactive effect of polymorphisms in PEMT, BHMT and CHDH genes with choline/betaine intake on breast cancer risk among Chinese women. This hospital-based case–control study consecutively recruited 570 cases with histologically confirmed breast cancer and 576 age-matched (5-year interval) controls. Choline and betaine intakes were assessed by a validated FFQ, and genotyping was conducted for PEMT rs7946, CHDH rs9001 and BHMT rs3733890. OR and 95 % CI were estimated using unconditional logistic regression. Compared with the highest quartile of choline intake, the lowest intake quartile showed a significant increased risk of breast cancer. The SNP PEMT rs7946, CHDH rs9001 and BHMT rs3733890 had no overall association with breast cancer, but a significant risk reduction was observed among postmenopausal women with AA genotype of BHMT rs3733890 (OR 0·49; 95 % CI 0·25, 0·98). Significant interactions were observed between choline intake and SNP PEMT rs7946 (Pinteraction=0·029) and BHMT rs3733890 (Pinteraction=0·006) in relation to breast cancer risk. Our results suggest that SNP PEMT rs7946 and BHMT rs3733890 may interact with choline intake on breast cancer risk.
Major advances have been made over the past 30 years in the development of an integrated computational materials design (ICMD) technology. The hierarchical structure of its methods, tools, and supporting fundamental materials databases is reviewed here, with an emphasis on successful applications of CALPHAD (calculation of phase diagrams)-based tools as an example of ICMD, expressing mechanistic understanding in quantitative form to support science-based materials engineering. Opportunities are identified for rapid expansion of CALPHAD databases, as well as a major restructuring of materials education.
Previous epidemiological studies have revealed the anti-cancer effect of dietary circulating carotenoids. However, the protective role of specific individual circulating carotenoids has not been elucidated. The purpose of this study was to examine whether serum carotenoids, including α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin, could lower the risk for breast cancer among Chinese women. A total of 521 women with breast cancer and age-matched controls (5-year interval) were selected from three teaching hospitals in Guangzhou, China. Concentrations of α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin were measured using HPLC. Unconditional logistic regression models were used to calculate OR and 95 % CI using quartiles defined in the control subjects. Significant inverse associations were observed between serum α-carotene, β-carotene, lycopene, lutein/zeaxanthin and the risk for breast cancer. The multivariate OR for the highest quartile of serum concentration compared with the lowest quartile were 0·44 (95 % CI 0·30, 0·65) for α-carotene, 0·27 (95 % CI 0·18, 0·40) for β-carotene, 0·41 (95 % CI 0·28, 0·61) for lycopene and 0·26 (95 % CI 0·17, 0·38) for lutein/zeaxanthin. However, no significant association was found between serum β-cryptoxanthin and the risk for breast cancer. Stratified analysis by menopausal status and oestrogen receptor (ER)/progesterone receptor (PR) showed that serum α-carotene, β-carotene, lycopene and lutein/zeaxanthin were inversely associated with breast cancer risk among premenopausal women and among all subtypes of ER or PR status. The results suggest a protective role of α-carotene, β-carotene, lycopene and lutein/zeaxanthin, but not β-cryptoxanthin, in breast cancer risk.
X-ray powder diffraction data for 1-(4-Nitrophenyl)-2-piperidinone, C11H12N2O3, are reported [a = 9.514(3) Å, b = 12.308(6) Å, c = 9.175(1) Å, α = 90°, β = 91.811(2)°, γ = 90°, V = 1073.94 Å3, Z = 4, ρcal = 1.362 g cm−3 and space group P21/n]. All measured lines were indexed and are consistent with the P21/n space group. No detectable impurities were observed.
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;
Thermal stress can induce birefringence in a laser medium, which can cause depolarization of the laser. The depolarization effect will be very severe in a high-average-power laser. Because the depolarization will make the frequency doubling efficiency decline, it should be compensated. In this paper, the thermal characteristics of two kinds of materials are analyzed in respect of temperature, thermal deformation and thermal stress. The depolarization result from thermal stress was simulated. Depolarization on non-uniform pumping was also simulated, and the compensation method is discussed.
Poly(L-lactide)/poly(para-dioxanone) (PLLA/PPDO) (85/15 w/w) blends with 0, 1, 3, and 5 wt% poly(para-dioxanone-co-L-lactide) (PDOLLA) as a compatibilizer were prepared by solution coprecipitation. The in vitro hydrolytic degradation (HD) of blend bars with different contents of PDOLLA was studied by immersing the bars in a phosphate buffer solution (PBS) at pH 7.49. To estimate the degradation of blend bars, the weight loss, water absorption, thermal properties, surface morphology, and mechanical properties of blend bars, as well as the pH value changes of the PBS, were studied for 8 wk of HD. By adding 1 and 3 wt% PDOLLA, the weight loss of PLLA/PPDO (85/15 w/w) blends increased from 6.4 to 6.8 and 7.4% after 8 wk of HD, 6.2 and 15.6% increment, respectively, while, the average tensile strength of PLLA/PPDO (85/15 w/w) blends for 2–8 wk of HD increased from 25.8 to 29.0 MPa and 31.0 MPa, 12.4 and 20.2% increment, respectively. Considering their good mechanical properties and HD rate, the PLLA/PPDO (85/15 w/w) blends with 1 and 3 wt% PDOLLA are potential to be used as a medical implant material.
Large volume fractions of Mn–Ni–Si (MNS) precipitates formed in irradiated light water reactor pressure vessel (RPV) steels cause severe hardening and embrittlement at high neutron fluence. A new equilibrium thermodynamic model was developed based on the CALculation of PHAse Diagrams (CALPHAD) method using both commercial (TCAL2) and specially assembled databases to predict precipitation of these phases. Good agreement between the model predictions and experimental data suggest that equilibrium thermodynamic models provide a basis to predict terminal MNS precipitation over wider range of alloy compositions and temperatures, and can also serve as a foundation for kinetic modeling of precipitate evolution.
The high repetition rate 10 J/10 ns Yb:YAG laser system and its key techniques are reported. The amplifiers in this system have a multi-pass V-shape structure and the heat in the amplifiers is removed by means of laminar water flow. In the main amplifier, the laser is four-pass, and an approximately 8.5 J/1 Hz/10 ns output is achieved in the primary test. The far-field of the output beam is approximately 10 times the diffraction limit. Because of the higher levels of amplified spontaneous emission (ASE) in the main amplifier, the output energy is lower than expected. At the end we discuss some measures that can improve the properties of the laser system.