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The method of high temperature thermal diffusion was successfully applied for doping Si impurities into cubic boron nitride (cBN) crystals. X-ray photoelectron spectra (XPS) and the current–voltage ( I – V ) characteristics at different temperatures were respectively used for analyzing the chemical states and the activation energy of Si impurity in cBN. According to the XPS results, Si impurities mainly replace B atoms bonding with the adjacent N atoms and become donors in cBN. Without surface cleaning, there are a lot of C and O contaminations on the surface of cBN, so a small quantity of C–Si and Si–N–O bonds also exist at the surface of cBN. Most Si impurities distribute in the shallow layer underneath the surface of cBN. Based on the electric measurement, Si impurities in cBN usually have the activation energy beyond 0.4 eV, and they can only be slightly ionized at room temperature, therefore the resistivity of Si-doped cBN is still high, and the space charge limited current becomes the main conductive mechanism in cBN. However, the conductivity of Si-doped cBN can rapidly increase with the temperature. In addition, the activation energy and the concentration of Si impurity in cBN can be affected by the temperature and the time of thermal diffusion, which needs to be verified further.

Sertraline, one of the oldest antidepressants, remains to be the most efficacious treatment for depression. However, major depression disorder (MDD) is characterized by altered emotion processing and deficits in cognitive control. In cognitive interference tasks, patients with MDD have shown excessive hypothalamus activity. The purpose of this study was to examine the effects of antidepressant treatment (sertraline) on hypothalamus-anchored resting brain circuitry. Functional magnetic resonance imaging was conducted on depressed patients(n=12)both before and after antidepressant treatment. After eight weeks of antidepressant treatment, patients with depression showed significantly increased connectivity between the hypothalamus and dorsolateral prefrontal cortex, orbitofrontal cortex, anterior cingulate cortex, insula, putamen, caudate, and claustrum. By contrast, decreased connectivity of the hypothalamus-related areas was primarily located in the inferior frontal gyrus, medial frontal gyrus, cingulated gyrus, precuneus, thalamus, and cerebellum. After eight weeks of antidepressant therapy, 8 out of the 12 depressed subjects achieved 70% reduction or better in depressive symptoms, as measured on the Hamilton depression rating scale. Our findings may infer that antidepressant treatment can alter the functional connectivity of the hypothalamus resting brain to achieve its therapeutic effect.

Unpredictable and inevitable perturbations during welding have adverse effects on the uniformity of weld penetration degree. Hence feedback control of weld penetration is necessary for assuring the welding quality. The backside weld bead width, regarded as a representation of penetration state, is measured usually by a structured-light sensor during the welding process. However, the structured-light method can only measure the width of the solidified weld behind the weld pool, but not the weld pool width, owing to the specular weld pool surface, thermal radiation and the possible arc light. It will introduce a time delay into the penetration control system. A novel low-cost visual technique of acquiring the backside weld pool width is developed in this paper, and the closed-loop control of weld penetration is achieved during gas tungsten arc welding (GTAW) for aluminum alloy. The parallel light is projected onto the weld pool backside, and the outline of the weld pool is highlighted because of the different reflection from the plate’s flat surface and the weld pool’s convex surface. Changes in the plate geometry are introduced during the experiments to perturb the welding process. Results show that stable penetration is maintained despite the perturbation.

In order to solve the problem that the information sharing level of educational resources is not high in the cloud computing environment, it is required to improve the design of educational resource information sharing algorithm in cloud computing environment. Therefore, an educational resource information sharing algorithm based on big data association mining and quasi-linear regression analysis is proposed. In this algorithm, information fusion and comprehensive measurement index system reconstruction are performed to resource distribution information of the educational resource database based on attribute type and semantic ontology characteristics. The simulation results show that the algorithm performs well in convergence during resource scheduling in educational resource information sharing and can provide average sharing level up to 0.9247, so this algorithm can be adopted to allocate resources in a balance way.

The polarities of a kind of plate-like and color-zoning cubic boron nitride (cBN) crystal were extensively investigated by microscopy, chemical etching, XPS, Raman scattering, and current–voltage measurements. The {1 1 1}B faces and { 1 ¯ 1 ¯ 1 ¯ } N faces of the cBN samples can be easily distinguished by optical microscope as there are a lot of defects incorporate in { 1 ¯ 1 ¯ 1 ¯ } N sectors serving as the color centers, while the {1 1 1}B sectors have less defects and are nearly colorless. Both XPS and Raman spectra also revealed the uneven distributions of N vacancies and substitutional impurities in cBN crystals. The determination of {1 1 1}B faces and { 1 ¯ 1 ¯ 1 ¯ } N faces can also be verified by the results of the chemical etching because the { 1 ¯ 1 ¯ 1 ¯ } N faces have much faster etch rates than the {1 1 1}B faces. According to XPS, the {1 1 1}B faces have more C and O contaminations than the { 1 ¯ 1 ¯ 1 ¯ } N faces, however the { 1 ¯ 1 ¯ 1 ¯ } N faces have larger atomic ratio of B:N after surface cleaning by Ar+ sputtering. In the Raman spectra of the { 1 ¯ 1 ¯ 1 ¯ } N sectors of cBN, several small broad infrared-active phonon bands emerge nearby TO and LO modes because of the disorder-activated Raman scattering. As for the {1 1 1}B sectors, this phenomenon disappears. In addition, the {1 1 1}B faces have much smaller leakage current than the { 1 ¯ 1 ¯ 1 ¯ } N faces, which indicates that the {1 1 1}B sectors have higher crystalline quality.

We present research on the development of a collaborative searching system for ecommerce shopping, based on domain specific requirements of retail shopping. We describe the design rationale for the system development and inclusion of collaborative search features, including search, chat, clipboard, product suggestions, shared views, and shopping cart. Our research goal is to understand whether collaborative searching tools are useful in supporting actual collaborative shopping tasks. In addition to describing the system development, we report findings from some preliminary user study. The findings highlight that collaborative search systems for domain specific areas such as online shopping can support collaborative searching, shared views, and group communication to aid in the completion of collaborative tasks.

With the social progress and development in China, market competition becomes increasingly fierce. In order to seek more long-term development, China has proposed higher requirements over the cause of education, which takes the training of comprehensive talents as the main objective and transmits more talents to promote social development. On this basis, it is an inevitable choice to apply a new teaching method in the general physics experiment course. As an innovative teaching method, peer instruction, in the practical application, can effectively stimulate students' interests in studies, get them actively involved, develop good experimental creation ability and physical literacy, train their logical thinking capacity, and have a far-reaching impact on the comprehensive development of students' overall quality. As a result, this paper mainly analyzes the application of peer instruction in the general physics experiment course, combines with the actual situation, and objectively describes its key application points and roles, in order to better enhance the teaching effects of the physics experiment course. In the traditional teaching, teacher is the main body of classroom, there is little interaction between teachers and students, students often do not dare to express their opinions, and teachers attach little importance to questions asked by students, which seriously inhibit students' learning efficiency. Such teaching conditions make it hard to doubt teachers. Nevertheless, in Western countries, this cramming teaching method has been replaced as early as the end of last century. They adopt new teaching methods, focus on the cultivation of students' self-learning ability and overall quality, encourage students to actively participate in learning and dare to doubt teachers, and carry out teaching discussions. After comparing with the current educational conditions between China and the US, relevant scholars have found that Chinese students study very hard, have very solid basic skills, and they are good at coping with all kinds of tests, yet they show poor practical abilities, inadequate flexibility, and do badly in asking questions and solving problems. In the teaching of physics experiment, Chinese students show defects in practical ability and innovation ability. The training of practical ability and innovation ability for college students has become a priority for the current teaching reform of the physics experiment course.

Based on the classical polarization theory, we studied and specified the physical mechanism of the electric-field-induced (EFI) Pockels effect and optical rectification in the space charge region of a near-intrinsic silicon sample with the planar capacitor structure. Especially, the effect of the applied DC bias on these EFI effects was investigated. The results show that the electro-optic signal from Pockels effect in silicon linearly increases with the applied DC voltage and the modulating voltage, and the signal of optical rectification is linearly enhanced by the DC bias as well, but the polarization characteristic of optical rectification does not vary. The enhancement of these EFI effects is mainly owed to the strengthening of the built-in field and the extension of the space charge region in the silicon sample. The Kerr effect of silicon was also detected and contrasted against the EFI Pockels effect, and it is verified that the EFI Pockels effect is much stronger than the Kerr effect in the silicon sample. These EFI effects are significant for the development of silicon photonics or silicon optoelectronics.

The defects, impurities and their bonding states of unintentionally doped cubic boron nitride (cBN) single crystals were investigated by X-ray photoelectron spectroscopy (XPS). The results indicate that nitrogen vacancy (V N ) is the main native defect of the cBN crystals since the atomic ratio of B:N is always larger than 1 before Ar ion sputtering. After sputter cleaning, around 6 at% carbon, which probably comes from the growth chamber, remains in the samples as the main impurity. Carbon can substitute nitrogen lattice site and form the bonding states of C B N or C B, which can be verified by the XPS spectra of C1s, B1s and N1s. The C impurity (acceptor) and N vacancy (donor) can compose the donor–acceptor complex to affect the electrical and optical properties of cBN crystals.

Different electro-optic effects, such as Kerr effect, Pockels effect induced by the electric field or strain, and plasma dispersion effect exist in silicon. Experimentally distinguishing these effects is necessary for designing silicon-based electro-optic devices. According to their different polarization dependencies and frequency responses, these effects are measured and distinguished successfully via a transverse electro-optic modulation experiment based on the near-intrinsic silicon sample. The results indicate that Pockels effect induced by the electric field or strain is primary among these effects in the near-intrinsic silicon sample.

Weld joint detecting technology is significant and indispensable to intelligent welding manufacturing. And vision sensing is considered as a promising weld joint detecting technology, with the advantages of rich information, non-contact measuring, high accuracy and anti-electromagnetic interference. Many structural components used in the aerospace field are manufactured through welding with tight butt joints. However, the conventional structured light method is not suitable for the detection of tight butt joints, since they rely on the light stripes' geometric distortion caused by the grooves. This study presents a real-time visual method for the tight butt joints' detection. Uniform surface light is employed to highlight tight butt joint and acquire 2D information, and structured light with a double-line pattern is projected onto the seam to acquire 3D point cloud data by optical trigonometry. Surface fitting with moving Least Squares (MLS) method is conducted in an iterative manner to combine 2D and 3D information and calculate the seam's positions and poses. Experimental results indicate that the proposed method is capable of detecting stably and accurately tight butt joints with a gap of less than 0.2 mm. The technique has the potential to be applied in tracking tight butt joints of complex structures in the aerospace industry for an automatic welding process.

In this Letter, we have demonstrated significant electric field induced (EFI) optical rectification (OR) effects existing in the surface layers of germanium (Ge) and measured the distributions of EFI OR signals along the normal directions of surface layers of Ge samples. Based on the experimental results, the ratios of the two effective second-order susceptibility components χzzz(2eff)/χzxx(2eff) for Ge(001), Ge(110), and Ge(111) surface layers can be estimated to be about 0.92, 0.91, and 1.07, respectively. The results indicate that the EFI OR can be used for analyzing the properties on surface layers of Ge, which has potential applications in Ge photonics and optoelectronics.

Making rural settlements of Mountainous Regions in Western Sichuan as the study objects and using symbolic statistical methods, then combining the case study of Daofu County, the paper analyzes the negative impact of the scattered rural settlements on infrastructure construction, farmers’ income increase and mountain ecological reconstruction in mountainous regions of western Sichuan. The results indicate that economic density is positively related to both rural settlements density (R 2=0.73) and rural population density (R 2=0.77), and it is the same for relationship between towns density and rural settlements density (R 2=0.88) and between towns density and economic density (R 2=0.71), and the scattered distribution pattern of the rural settlements and shortage of economic centers is a major factor to the lagged socioeconomic development. On the eco-economic zoning to Daofu County, the paper indicates the spatial distribution model and the industrial development model of the rural settlements need to be changed, and rural population should be concentrated in larger rural settlements with development of off-farm industries while infrastructure construction is to reinforced.

Osteosarcoma is a high-grade malignant bone neoplasm. Although the introduction of chemotherapy has reduced its mortality, >50% of patients develop chemoresistance and have an extremely poor prognosis due to pulmonary metastasis. Several molecular pathways contributing to osteosarcoma development and progression have recently been identified. Various studies have addressed the genes involved in the metastasis of osteosarcoma. However, the highly complex molecular mechanisms of metastasis remain to be elucidated. Recent studies have emphasized causative links between aberrant microRNA expression patterns and osteosarcoma progression. miR-1908 is dysregulated in certain human types of cancer. The expression pattern, clinical significance and biological role of miR-1908 in osteosarcoma, however, remain largely undefined. In the present study, we showed that miR-1908 was markedly upregulated in osteosarcoma cells and tissues compared with normal bone tissues using RT-qPCR. miR-1908 upregulation in osteosarcoma tissues was significantly associated with cell proliferation, invasion, advanced TNM stage and tumor growth. Both gain- and loss-of-function studies showed that miR-1908 markedly increased the ability of osteosarcoma cells to proliferate and to invade through Matrigel in vitro. Analyses using mouse xenograft model revealed that xenografts of miR-1908 stable-expressing osteosarcoma cells exhibited a significant increase in tumor volume and weight, compared with the control group. Subsequent investigations revealed that miR-1908 directly inhibited the expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Using a luciferase reporter carrying the 3'-untranslated region (3'-UTR) of PTEN, we identified PTEN as a direct target of miR-1908. Collectively, the results showed that, miR-1908 promotes proliferation and invasion of osteosarcoma cells by repressing PTEN expression.

Ab initio calculations of lattice constants, lattice stabilities of ZnX (X=O, S, Se, Te) at different electronic temperatures (Te) have been performed using generalized gradient approximation (GGA) pseudopotential method within the density functional theory (DFT). The calculated phonon frequencies of ZnX at Te = 0 eV accord well with the experimental and other theoretical values. Firstly, it is indicated that the lattice constants of ZnX increase and all the phonon frequencies reduce as Te increases. Additionally, the transverse-acoustic phonon frequencies of ZnX are imaginary with the elevation of Te, namely the lattices of ZnX become unstable under ultrafast intense laser irradiation. Moreover, the transverse optical mode-longitudinal optical mode (LO-TO) splitting degree of ZnX (X=S, Se, Te) gradually decreases as the electronic temperature increases, mainly due to the reason that the electronic excitation weakens the strength ionicity of ionic crystal ZnX under intense laser irradiation. However, the LO-TO splitting degree of ZnO firstly increases and then decreases with the increase of electronic temperature. After that, it can be helpful for understanding the mechanism of ultrafast intense laser induced semiconductors damage.

Oridonin is an active diterpenoid, which was extracted from traditional Chinese herbs and had been widely used in clinical treatment nowadays. Oridonin phosphate is one of the derivatives of oridonin. In the present study, we explored its anti-tumor effect and investigated the molecular mechanism of oridonin phosphate in breast cancer cell lines. Firstly, cell viability was analyzed by MTT assay. The breast cancer cells were treated with increasing concentrations of oridonin phosphate for 24, 48 and 72 h, respectively. The results demonstrated that oridonin phosphate inhibited the proliferation of MDA-MB-436 and MDA-MB-231 cells in a dose- and time-dependent manner. Next, cell apoptosis rate was detected in oridonin phosphate-treated breast cancer cells by Annexin V-FITC/PI dual staining analysis and the data demonstrated that oridonin phosphate induced cell apoptosis of breast cancer cells in time- and dose-dependent manner. Moreover, apoptosis-related proteins were detected by Western blotting analysis. The results showed that the expression level of Bax was up-regulated and the expression level of Bcl-2 was down-regulated. Meanwhile, the level of cleaved caspase-9 was significantly increased when the cells were treated with 40 μM of oridonin phosphate for 48 h, although the expression level of pro-caspase-9 was not obviously changed. All of the data revealed that mitochondrial apoptosis pathway may be involved in the cell apoptosis induced by oridonin phosphate in breast cancer cells. Importantly, the expression levels of autophagy-related protein beclin-1 and LC3-II were significantly higher in oridonin phosphate-treated breast cancer cell lines MDA-MB-436 and MDA-MB-231 for 48 h. Additionally, we further explored the relationship between apoptosis and autophagy specifically induced by oridonin phosphate in breast cancer cells. The result showed that inhibition of autophagy suppressed the cell apoptosis in oridonin phosphate-treated MDA-MB-436 cells. Taken together, the compound of oridonin phosphate simultaneously induced cell apoptosis and autophagy in breast cancer cells. Inhibition oridonin phosphate-induced cell autophagy suppressed the progression of cell apoptosis, which revealed that oridonin phosphate-induced autophagy participated in up-regulation of apoptosis in human breast cancer cells. It would provide some new clues for the therapy of breast cancer.

The electro-optic effects in silicon include Kerr effect, plasma dispersion effect, and Franz-Keldysh effect etc.. Silicon does not have the linear electro-optic effect in the bulk because of the inversion symmetry, which restricts the development of the silicon-based optoelectronics and silicon photonics. However, the electric field can destroy the inversion symmetry of silicon, and produce so-called electric-field-induced linear electro-optic effect. In intrinsic or near-intrinsic silicon, these electro-optic effects exist simultaneously. In this paper, a transverse electro-optic modulation system was designed to detect these electro-optic effects. The electric-field-induced linear electro-optic effect was demonstrated in the space charge region of silicon sample and distinguished from Kerr effect based on the different frequency response. The relationship between the linear electro-optic signal and the azimuth angle of the analyzer was measured too, which was used for distinguishing the electric-field-induced linear electro-optic effect from the plasma dispersion effect. The results showed that the electric-field-induced linear electro-optic effect was stronger than Kerr effect and the plasma dispersion effect in the near-intrinsic silicon samples.

In the promotion of agricultural structure adjustment, Jili District Government in Henan Province cultivated the management model of “Three Fives”, i.e. the organizational model of “Five Alliances”, the operational model of “Five Links” and the management model of “Five Unions”. It has been proved that it is of great help to the adjustment and optimization of agricultural structure if the government plays a better role of bridge or ties and performs its functions of comprehensive services. In details, the government should integrate various resources, such as scientific institution, financial department, peasant, company and media to construct modern agricultural organization and provide technological information, research resources, project, start-up capital and scientific demonstration for peasants; establish a public service platform to provide information service for peasants' cultivation, base management, company organization, factory's processing, market forecast and scientific service for the development of product market; establish an agricultural management platform to realize unified management and supervision of the whole process, including seed supply, technical training, product label, product pricing and marketing.

Making rural settlements of mountainous regions in western Sichuan as the study objects and using symbolic statistical methods, then combing Daofu County as the case study, the paper analyzed the negative impact of scattered rural settlements to road construction and other infrastructure in mountain regions of western Sichuan. The results showed that the road utilization was in state of longer road length per capita, but smaller road density and bad utilization and profit, and most rural settlements were in poverty with no road, infirmary, school and electricity net, and the scattered distribution of rural settlements was a major factor. It indicates that road construction patterns should be changed in mountainous regions of western Sichuan, the scattered rural settlements should be resettled in the range of whole county, the spatial distribution pattern of settlements should be reconstructed, and the scale of settlements and population should be enlarged in the service range of current road. On the eco-economic zoning of the Daofu county, the three road construction patterns were indicated based on rural settlements spatial reconstruction in mountainous regions of western Sichuan, patterns based on national road and central villages, patterns based on key townships, common townships and central village, and patterns based on key townships and central villages.

Macropore silicon etching with photo-electro-chemistry was carried out under different experimental conditions, including etching voltage, current density and wave length of optical source et al. The surface, diameter of pore and wall of the macropore silicon were observed with Scanning Electronic Microscope (SEM) and Metallographic Microscope. The influencing factors on morphology of pore were analyzed. Experimental parameters for fabricating high properties macropore silicon were also determined. Macropore silicon with depth of pores up to 300 ?m and aspect ratios more than 75 was etched with photo-electrochemistry.

The MEMS silicon-micro-machining is the main MEMS technology, which includes the surface-silicon-micro-machining and the bulk-silicon-micro-machining technology; however the bulk-silicon micro-machining technology has a wide application. In this paper, the formation procession of electron multiplier on n-type Silicon substrate by bulk-silicon-micro-machining technology was investigated. A series of electrochemical etching experiments and tests were carried out in three poles electrobath system using HF electrolyte with different concentration. The rate of photoelectrochemical etching on the macropore depends on a few technological parameters, such as doping concentration, operating bias, illumination intensity of the light, HF concentration, and so on. It was found that the formation possibility of the macropore array is directly correlated with crystal orientation of n-type Silicon substrate.

Microsphere plate (MSP) is a new type of electron multiplier device. It is similar to the traditional microchannel plate (MCP) in dimensions and model of operation. Compared with the MCP electron multiplier, the MSP has some unique characteristics such as a high electron gain, without ion feedback and easy to be fabricated, thus it is widely used in the fields of imaging and detecting. However, there are some key technologies to fabricate a satisfied MSP. In this paper, the whole fabrication process of MSP was introduced and some of major processes such as the formation of glass beads, the sintering of MSP body, and the formation of dynode and electrodes were specially discussed. At the end of the paper, the optimal processed for the fabrication of MSP was given.

With the two point correlation function, we investigate the effect of the correction parameters on the thermalization of Plasma in the background corrected by conformal anomaly. In terms of the AdS/CFT correspondence, this equals to probe the collapse of a shell of dust by the like-space geodesic in the background corrected by conformal anomaly. The result shows that as the parameter corrected by conformal anomaly increases, the thermalization time for the plasma evolving from the non-equilibrium state to the equilibrium state is longer. We also get the fitted function of the thermalization curve, and based on the function, we further obtain the thermalization velocity and thermalization acceleration. With the thermalization velocity curve, we find the thermalization process can be divided into a acceleration phase and a deceleration phase, the phase transition point raises as the parameter corrected by conformal anomaly increases.

By observing two-photon response and anisotropy of the light-induced voltage in Si-Al Schottky barrier potential of the Si MSM (Metal-Semiconductor-Metal) planar structure two-photon response optical detector. It is certified from the experimental and theoretical analysis that the built-in electric field generated by the Schottky barrier potential will induce the phenomena of optical rectification in Si photodiode. Thus, it is deduced that there must be double-frequency absorption (DFA) caused by phase-mismatch in the mechanism of two-photon response of Si photodiode. If the intensity of the built-in electric field is strong enough, the DFA will be the main feature of the two-photon response.

In this paper, numerical analysis was investigated for the double-clad fiber lasers and experimental study on the Yb3+-doped double-clad fiber lasers was performed. The results shown that the output power increased monotonically with absorbed power, and in lossy cavity the output power is less than in the lossless cavity. The output power decreases for the lossy fiber with the reflectivity of output coupler. There was an optimum fiber length to reach a maximum output and the optimum length was mainly dependent on the loss coefficient. In experiment we obtained an output power of 21.6W, slope efficiency of 54% by using Yb3+-doped double-clad fiber and 40W LD pump source.

The MCP ion barrier film in low-light-level imaging tube and its process techniques were introduced in this paper. The electron transmittance of this film was studied. The results of half field-of-view testing comparisons and the concept of dead voltage were presented. The dead voltage curve and the relation between dead voltage and thickness of film were tested. The composition of film was analyzed by XPS.

The formation of deep macropore array of p-type Silicon in HF electrolyte has been investigated. Then a series of electrochemical etching experiments and tests were carried out in three poles electrobath using different concentration HF electrolyte. HF concentration is a very important factor that determined whether electrochemical reaction was accomplished or not. By means of theoretical analysis and investigation, it is generally assumed that etching proceeds through sequential reaction of Si-H groups with F- to form Si-X, which determined whether electrochemical etching reaction was carried out or not. The electrochemical etching of p-type Silicon macropore array in aqueous fluoride solutions is satisfied with economic requirements for costs of fabricating deep macropores. The consequences are benefit to Silicon electrochemical deep macropore array etching technology.

This paper reports on a silicon micro-hole arrays (Si-MHA) prepared by Inductively Coupled Plasma (ICP) etching, a dry etching method. By ICP etcher, we carried out several experimental researches and process exploration for micromachining Si-MHA. The mechanism of lateral etching, sidewall passivation, gas micro-transport and some process parameters in Si-MHA micromachining, such as gas switching time, flow rate, etching rate, were analyzed. The footing effect, lag effect, longitudinal strips and RIE grass effect occurred in the ICP etching process were also studied. These process problems had reappeared in the micro-hole arrays process though these problems had be solved in the field of integrated circuits process and microelectromechanical system (MEMS). The study results reported here had demonstrated a Si-MHA that the diameter was 15 μm, the center distance 30 μm, and the depth 240 μm prepared by ICP, and had led the author to believe that the deep pore structure and the deep trench with high aspect ratio were very different in etching process. The former is a closed structure for the gas transport, and the latter is an open structure, so the process of deep hole structure is a puzzle in micromachining and MEMS technology.

This paper reports on a silicon mcrochannel arrays prepared based on bulk-micromachining technology, dry etching technology and electrochemical process respectively. In dry etching, a silicon microchannel plate (Si-MCP), with 15-30 aspect ratio of the microchannel, 6-20 µm, 6-8 µm space and 150-300µm depth, were prepared by Inductively Coupled Plasma (ICP). The phenomenon ofplasma etching lag and the morphology ofthe microchannel array in dry processing were analyzed and discussed.In wet process, both p-type and n-type silicon was selected as the substrate for microchannel arrays. A inducing pit arrays was first prepared by oxidation, lithography, KOH etching, and then a square channel arrays that has 4 µm length of side and 2 µm space were formed by electrochemical etching in hydrofluoric acid in three poles electrolyzing cell, which can yield straight holes with high aspect ratio. The electrochemical mechanism of silicon anisotropy etching, the parameters of three pole electrolyzing cell, and the inducing pit and channel morphology were investigated and discussed. The results shows that the high aspect ratio of silicon microchannel arrays can be made by both dry and wet etching processes. The ICP process yield a microchannel arrays with uneven, re-entrant, notched and ripples surface within the channel. The electrochemical process for silicon microchannel arrays has lower cost than ICP process.

Although the benefit of reducing blood pressure for primary and secondary prevention of stroke has been established, the effect of antihypertensive treatment in patients with acute ischemic stroke is uncertain.To evaluate whether immediate blood pressure reduction in patients with acute ischemic stroke would reduce death and major disability at 14 days or hospital discharge.The China Antihypertensive Trial in Acute Ischemic Stroke, a single-blind, blinded end-points randomized clinical trial, conducted among 4071 patients with nonthrombolysed ischemic stroke within 48 hours of onset and elevated systolic blood pressure. Patients were recruited from 26 hospitals across China between August 2009 and May 2013.Patients (n = 2038) were randomly assigned to receive antihypertensive treatment (aimed at lowering systolic blood pressure by 10% to 25% within the first 24 hours after randomization, achieving blood pressure less than 140/90 mm Hg within 7 days, and maintaining this level during hospitalization) or to discontinue all antihypertensive medications (control) during hospitalization (n = 2033).Primary outcome was a combination of death and major disability (modified Rankin Scale score ≥3) at 14 days or hospital discharge.Mean systolic blood pressure was reduced from 166.7 mm Hg to 144.7 mm Hg (-12.7%) within 24 hours in the antihypertensive treatment group and from 165.6 mm Hg to 152.9 mm Hg (-7.2%) in the control group within 24 hours after randomization (difference, -5.5% [95% CI, -4.9 to -6.1%]; absolute difference, -9.1 mm Hg [95% CI, -10.2 to -8.1]; P .001). Mean systolic blood pressure was 137.3 mm Hg in the antihypertensive treatment group and 146.5 mm Hg in the control group at day 7 after randomization (difference, -9.3 mm Hg [95% CI, -10.1 to -8.4]; P .001). The primary outcome did not differ between treatment groups (683 events [antihypertensive treatment] vs 681 events [control]; odds ratio, 1.00 [95% CI, 0.88 to 1.14]; P = .98) at 14 days or hospital discharge. The secondary composite outcome of death and major disability at 3-month posttreatment follow-up did not differ between treatment groups (500 events [antihypertensive treatment] vs 502 events [control]; odds ratio, 0.99 [95% CI, 0.86 to 1.15]; P = .93).Among patients with acute ischemic stroke, blood pressure reduction with antihypertensive medications, compared with the absence of hypertensive medication, did not reduce the likelihood of death and major disability at 14 days or hospital discharge.clinicaltrials.gov Identifier: NCT01840072.

Introduced the construction of the experiment system of the laser probe measurements based on electro-optic sampling technique. Analyzed the relationship between the width of the optical pulses and the signal noise ratio of detection. The function of different stage circuit internal to the high-speed dynamic divider circuit chip have been measured with the double-frequency phase sweeping technique. A detail analysis about the chip failure have been given.

The nonlinear photoresponse to a 1.56-\mu m infrared continuous wave laser in semi-insulating (SI) galliumarsenide (GaAs) is examined. The double-frequency absorption (DFA) is responsible for the nonlinear photoresponse based on the quadratic dependence of the photocurrent separately on the coupled optical power and bias voltage. The electric field-induced DFA remarkably affects the native DFA in SI GaAs. The surface electric field or the surface band-bending of SI GaAs significantly affects the magnitude variation of the photocurrent and dark current.

The transverse electro-optic (EO) modulation system is built based on cubic boron nitride (cBN) single crystals unintentionally doped and synthesized at a high pressure and high temperature. The photoelectric output of the system includes two parts that can be measured respectively and the value of elements in the linear EO tensor of the cBN crystal can be obtained. This method does not need to measure the absolute light intensity. All of the surfaces of the tiny cBN crystals whose hardness is next to the hardest diamonds are {111} planes. The rectangular parallelepiped cBN samples are obtained by cleaving along {110} planes and subsequently grinding and polishing f112g planes of the tiny octahedral cBN flakes. Three identical non-zero elements of the EO tensor of the cBN crystal are measured via two sample configurations, and the measured results are very close, about 3.68 and 3.95 pm/V, respectively, which are larger than the linear EO coefficients of the general III-V compounds.

Properties of two-photon response in a [111]-cut nearly-intrinsic Si hemisphere photodetector are studied. The measured photocurrent of the photodetector responding to the 1.32μm continuous wave laser shows a quadratic dependence on the coupled optical power and is saturated with the bias voltage. Also, the photocurrent is independent of polarization. Such properties are in good agreement with the theory of two-photon absorption. The isotropic photocurrent generated from the [111]-cut Si hemisphere is compared to the anisotropic one induced in the [110]-cut Si sample and the ratio of χxxxx/χxxyy for silicon performing at 1.32 μm is calculated to be 2.4 via the fitted function of the anisotropic photocurrent from the [110]-cut sample.

We present a unique dataset of student source-based argument essays to facilitate research on the relations between content, argumentation skills, and assessment. Two classroom writing assignments were given to college students in a STEM major, accompanied by a carefully designed rubric. The paper presents a reliability study of the rubric, showing it to be highly reliable, and initial annotation on content and argumentation annotation of the essays.