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Background: Hepatocellular carcinoma is one of the most common malignant tumors found all over the globe. Despite advances in surgery and chemotherapy, the five-year survival rate of patients with hepatocellular carcinoma is still low. It is known that the proliferation of hepatocellular carcinoma cells is closely related to the occurrence, development and prog- nosis of hepatocellular carcinoma. The present work investigates the expression of microRNA-489 (miR-489) in human hepatocellular carcinoma cells and its effect on the biological behavior of human hepatocellular carcinoma cells. Methods: The expression of miR-489 by fluorescence quantitative PCR detection in 30 patients with hepatoblastoma of liver cancer tissues and adjacent tissues was studied. Also, the determination of hepatoblastoma in four cell lines with differ- ent metastatic potential (HR8348, HCT116, HT29 and HEPG2) and the expression of miR-489 during miR-489 simulation process was studied. MTT assay, flow cytometry and Western blot analysis were performed to know the cell proliferation to detect the changes in cell cycle, apoptosis of cells, and SOX4 gene expression respectively. Results: RT-PCR results showed that the cells compared with pre-cancerous tissue, the expression level of miR-489 in hepatocellular carcinoma tissues than in adjacent tissue significantly decreased (P 0.05); but miR-489 expression could induce apoptosis, compared with the control group, the apoptosis of miR-489 mimics was significantly increased and the difference was statistically significant (P < 0.05). Conclusion: In conclusion, miR-489 can significantly inhibit the occurrence and development of hepatocellular carcinoma cells. The mechanism may be down regulated by the expression of SOX4 and inhibit cell proliferation. Further this study showed that the tumor cells SOX4 gene as a regulatory factor target the genes of miR-489 in hepatocellular carcinoma. Keywords: Hepatocellular carcinoma; mircroRNA-489; SOX4; apoptosis.

A simulation model of surface to ground missile is proposed in this paper. The model consists of several modules, such as calculating the flight state of missile, judging the distance between missile and target, calculating the hit time of missile, calculating the damage range of missile and calculating the damage condition of target. The main process, data structure and information of the model are introduced. The model not only reflects the main function process of air to ground missile, but also is easy to implement.

Introduction We aimed to explore the real-world clinical application value and challenges of metagenomic next-generation sequencing (mNGS) for pulmonary infection diagnosis. Methods We retrospectively reviewed the results of mNGS and conventional tests from 140 hospitalized patients with suspected pulmonary infections from January 2019 to December 2020. The sample types included bronchoalveolar lavage fluid, lung tissue by transbronchial lung biopsy, pleural effusion, blood, and bronchial sputum. Apart from the mNGS reports that our patients received, an extra comprehensive and thorough literature search was conducted. Results Significant differences were noticed in the positive detection rates of pathogens between mNGS and conventional diagnostic testing (115/140, 82.14% vs 50/140, 35.71%, P 0.05). Conclusion mNGS is a valuable tool for the detection of pulmonary infections, especially mixed pulmonary infections. The most common combinations we found were bacterial–fungal coinfection and bacterial–bacterial coinfection. Still, there are many challenges in the clinical application of mNGS in the diagnosis of pulmonary infections. There is still a lot of work to be done in interpreting the mNGS reports, because both clinical judgment and literature analysis strategy need to be refined.

An adaptive classification is developed as a hybrid of the eigenvector- and model-based decompositions of polarimetric SAR (PolSAR) image. It adopts the canonical models that widely used in model-based target decomposition to obtain an improvement for the well-known $H/\alpha$ classification. First, a correspondence principle is developed to adaptively select the matched canonical models. The models are parallelly combined in terms of the scattering similarity for a fine description of the scattering mechanism then. Twelve classes are finally achieved with each one carrying a unique symbol to indicate a specific scattering. The classification does not depend on a particular data set, avoids the hard partitioning, and solves the obscures in $H/\alpha$ . Comparison on real PolSAR image with $H/\alpha$ validates the better discrimination of radar targets.

Autonomous proximity operations have recently become appealing as space missions. In particular, the estimation of the relative states and inertia properties of a noncooperative spacecraft is an important but challenging problem, because there might be poor priori information about the target. Using only stereovision measurements, this study developed an adaptive unscented Kalman filter to estimate the relative states and moment-of-inertia ratios of a noncooperative spacecraft. Because the accuracy of the initial relative states has an effect on the estimation convergence performance, attention was also given to their determination. The target’s body-fixed frame was defined in parallel to the chaser’s initial body-fixed frame, and then the initial relative attitude was known. After formulating kinematic constraint equations between the relative states and multiple points on the target surface, particle swarm optimization was utilized to determine the initial relative angular velocity. The initial relative position was also determined under the assumption that the initial relative translational velocity was known. To estimate the relative states and moment-of-inertia ratios using the adaptive unscented Kalman filter, the relative attitude dynamic model was reformulated by designing a novel transition rule with five moment-of-inertia ratios, described in the defined target’s body-fixed frame. The moment-of-inertia ratios were added to the state space, and a new state equation with variant process noise covariance matrix Q was formulated. The measurement updating errors of the relative states were utilized to adaptively modify Q so that the filter could estimate the relative states and moment-of-inertia ratios in two stages. Numerical simulations of the adaptive unscented Kalman filter with unknown moment-of-inertia ratios and the standard unscented Kalman filter with known moment-of-inertia ratios were conducted to illustrate the performance of the adaptive unscented Kalman filter. The obtained results showed the satisfactory convergence of the estimation errors of both the relative states and moment-of-inertia ratios with high accuracy.

This paper constructed a new high speed and power density servo motor design scheme based on magnetic pole eccentricity proposed according to the requirements of electrical performance parameters. The analytical formulae were deduced in view of the theory of thick-walled elastic cylinders and the actual model by analytical calculations and finite element calculations. The structure strength of permanent magnet was analyzed. Furthermore, comprehensively comparing and analyzing the calculation results of the two methods verify the accuracy of the analytical calculation method and the rationality of the permanent magnet structure design. In brief, this paper provides a reference for the design of high-speed motor magnetic pole eccentricity.

On-orbit servicing for GEO targets has attracted great attention due to particular significance. In this study, the GEO nearby flying is considered, which denotes that the servicing spacecraft approaches GEO targets within tens of meters. Based on the analysis of differential spherical Earth gravity, J2 perturbation, third-body perturbation, and solar radiation pressure (SRP) between two spacecraft, a relative dynamics of GEO nearby flying is built, in which the differential SRP has great influence on relative motion. Therein, considering the differential SRP, an analytical solution to relative dynamics is obtained, which is an extension to CW equation’s solution. Based on the derived relative dynamics, a novel control method utilizing feedback compensation and artificial potential is developed for spacecraft orbital transfer and hovering at the desired position. During orbital transfer, a bounded space is constrained with maximum and minimum relative distance between two spacecraft. An improved repulsive potential based on Gauss function is designed to drive the servicer off the bound and guarantee the potential value converge to zero at the desired position. Meanwhile, a novel attractive potential about relative distance that drives the servicer to the desired position and to hover with high accuracy against perturbations is designed. Besides, a velocity potential with variable gain is designed to ensure that the servicer achieve the desired position without overshoot. The stability of the system is proved with Lyapunov theory, and the feasibility of the proposed control law is verified through numerical simulations with obvious advantages.

The target classification of interceptor system faces with the problems of high speed, short sampling time, and high echo fluctuation and so on. In order to distinguish the intercept target effectively, this paper proposes a method of echo difference with different frequency points. The data of two channels sampling from different frequency points, is compared to distinguish the target. This method can distinguish large threat projectile target and small non threat bullets target, reducing false alarm rate and avoiding mistaken injury to our own personnel under battlefield environment.

For the polarity test of the CT for 1, 000kV ultra-high voltage(UHV) infrastructure projects, the polarity layout method and test program of a main transformer, etc. were discussed under 3/2 complete serial connection mode in an all-round manner. The protection of 1, 000kV bus difference, circuit breakers, lines and high resistance, the polarity of a metering device CT and the receiving method of a secondary circuit were discussed; and a reasonable point polarity method was provided before actual production. The polarity configuration of CTs at the low-voltage side of an ultra-high voltage transformer body bushing, common windings, a voltage regulation-compensation transformer, a house transformer and a main transformer, and the calculation logic of protective devices were studied. The effect of essential factors such as actual wring, equivalent impedance, etc. on polarity were analyzed, and the adverse factor of voltage regulation position was pointed out. When the polarity at the high-voltage side of the housing transformer was being studied, it is strongly interfered by electromagnetic coupling. The selection scheme of CT secondary circuit was studied according to the requirements of different ultra-high voltage protective devices, and the point polarity measures of the voltage regulation-compensation transformer were explored according to protection calculation logic. When the polarity of the main transformer and the auxiliary transformer for a compensation transformer were being tested, the cause of interference among three phases due to the Y/Δ wiring method at HV and low sides of the main transformer was mainly discussed.

Based on the vectorial Rayleigh-Sommerfeld diffraction integral formulae, analytical expressions for a vectorial elliptical Gaussian beam’s nonparaxial propagating in free space are derived and used to investigate target beam’s propagation properties. As a special case of nonparaxial propagation, the target beam’s paraxial propagation has also been examined. The relationship of vectorial elliptical Gaussian beam’s intensity distribution and nonparaxial effect with elliptic coefficientαand waist width related parameterfωhas been analyzed. Results show that no matter what value of elliptic coefficientαis, when parameterfωis large, nonparaxial conclusions of elliptical Gaussian beam should be adopted; while parameterfωis small, the paraxial approximation of elliptical Gaussian beam is effective. In addition, the peak intensity value of elliptical Gaussian beam decreases with increasing the propagation distance whether parameterfωis large or small, and the larger the elliptic coefficientαis, the faster the peak intensity value decreases. These characteristics of vectorial elliptical Gaussian beam might find applications in modern optics.

Background: To study the changes of electroencephalogram (EEG) power spectrum in the elderly with mild cognitive dysfunction in resting and working memory task states. Methods: In this study, 40 patients with mild Alzheimer's disease (AD group), 40 patients with mild cognitive impairment (MCI group), and 40 normal controls (NC group) were enrolled. Their EEGs were recorded in resting and working memory task states. The EEG power spectrum, including δ, θ, α1, α2, β1, and β2, were analyzed from 10 channels: right and left frontal (F3, F4), central (C3, C4), parietal (P3, P4), temporal (T3, T4), and occipital (O1, O2). Results: In the resting state, the δ and θ powers from some regions in the AD group were higher than those in the NC group and the MCI group (p

The inverted-triangle permanent magnet interior rotor is a new type of motor rotor structure for vehicles. First, this paper introduces and qualitatively analyzes the inverted-triangle interior permanent magnet synchronous motor (IPMSM), and establishes the equivalent magnetic circuit model of the inverted triangle IPMSM under no-load and load conditions. Secondly, based on the equivalent magnetic circuit model, a preliminary design of an inverted-triangle IPMSM for an 8-pole 48-slot vehicle was carried out. Finally, the finite element software is used to optimize the rotor of the motor to obtain ideal electromagnetic performance. The simulation results show that with the same torque performance, the amount of permanent magnets of the inverted-triangle IPMSM is significantly less than that of the V-shaped IPMSM, which is beneficial to reducing the cost of motors for automobiles.

Fin field effect transistor (FinFET) is a most widely used structure when the field effect transistor is scaled down to 30 nm or less. And there are few studies on single-event transient of FinFET devices with gate length below 30 nm. The single-event-transient on FinFET with gate length below 30 nm is worth studying. The single-event-transient responses of bulk FinFETs with 30 nm, 40 nm, 60 nm and 100 nm gate length are examined by using the pulsed laser and technology computer-aided design (TCAD) simulation in this article. First, we use the pulsed laser to ionize the gate of the FinFET device and detect the transient drain current of the FinFET device. The experimental results show that there are obvious platforms for the transient drain current tails of FinFETs with different gate lengths, and the platform current increases as the gate length of FinFET becomes shorter. The charges collected in the platform of FinFET devices with gate lengths of 100, 60, 40, and 30 nm are 34%, 40%, 51%, and 65% of the total charge collected in transient drain current, respectively. Therefore, when the FinFET device with the gate length below 100 nm, the platform current will seriously affect the device performance. Second, we use TCAD to simulate the heavy ion single-event effect of FinFET device and study the generation mechanism of platform region in transient drain current. The TCAD simulation explains this mechanism. Laser or heavy ions ionize high concentration electron-hole pairs in the device. The holes are quickly collected and the high concentration electrons are left under the FinFET channel. High concentration electrons conduct source and drain, generating the source-to-drain current at the tail of the transient drain current. Moreover the source-drain conduction enhances the electrostatic potential below the FinFET channel and suppresses high-concentration electron diffusion, making source-to-drain current decrease slowly and form the platform. The transient drain current tail has a long duration and a large quantity of collected charges, which seriously affects FinFET performance. This is a problem that needs studying in the single-event effect of FinFET device. It is also a problem difficult to solve when the FinFET devices are applied to spacecraft. And the generation mechanism of the transient drain current plateau region of FinFET device can provide theoretical guidance for solving these problems.

The aim of the present study was to investigate the effects of hepatic blood inflow on liver function, liver ultrastructure and the regeneration of future liver remnant (FLR) following major hepatectomy in rats with liver cirrhosis. A rat model of cirrhosis was established through intraperitoneal injection of carbon tetrachloride for 8 consecutive weeks. Extensive liver resection and different blood inflow models by portal vein (PV) and/or hepatic artery (HA) stenosis were conducted on the cirrhosis rats. Animal models were constructed as follows: Control (group A), low-flow PV + high-flow HA (group B), low-flow PV + low-flow HA (group C), high-flow PV + high-flow HA (group D) and high-flow PV + low-flow HA (group E). Hepatic blood inflow was detected by laser speckle contrast analysis, liver function and pathological changes were analyzed, Masson staining was used to identify the fibrosis of the liver and Periodic acid-Schiff staining was used to identify glycogen synthesis and hepatocyte function. The liver cell ultrastructure was evaluated by transmission electron microscopy, and the expression of Ki-67 in hepatocytes and the weight of the FLR were recorded to determine the regeneration of the FLR. Five days after major hepatectomy and liver blood inflow modulation, pathological examination of the livers from groups B and C revealed less congestion and less extensive hepatocellular injury. The serum alanine aminotransferase level of group B at 1, 3 and 5 days after hepatectomy and blood inflow modulation was 460.9±31.7, 331.0±22.0 and 285.6±15.8 U/l, respectively (control group: 676.9±41.7, 574.9±28.0 and 436.1±32.7 U/l, respectively; P

In this study, a model predictive control (MPC) method is developed for a servicer spacecraft autonomously approaching a tumbling failed spacecraft at an ultraclose range. Flight safety and collision avoidance are basic requirements during the approach. Two types of a failed spacecraft with complex configurations are considered, and a double-ellipsoid composite envelope strategy is designed to model their keep-out zones. Given the keep-out zone of the servicer, two expanded ellipsoids are subsequently introduced to determine the collision and sufficient conditions for collision avoidance are derived by using the form of concave constraint. The tumbling motion of the target is considered, and a CW-based translational dynamics and derived attitude dynamics of the target are formulated to predict the motion of the docking point and keep-out zone. The MPC is formulated to drive the servicer tracking the docking point with collision avoidance and handle constraints including control input saturation and relative velocity bound. Convexification of the collision avoidance constraint and sequential convex programming are adopted for the implementation of MPC. Scenarios on the servicer with different initial positions approaching the target with different angular velocities are simulated, and the simulation results indicate that the proposed MPC method is effective.

This paper proposes a novel method to derive the junction temperature of a Silicon Carbide Schottky Barrier Diode (SiC SBD) when it is in operation. There is a correlation between the switching waveforms and the temperature, due to the material parameters and the carrier vary with the temperature. Estimating the Turn-on-delay time as a temperature sensitive electrical parameter (TSEP), the chip temperature in operation can be evaluated. The experiment is based on signal loop — dealing with the output signal of the chip by the peripheral circuits, then putting it as the switching signal to the chip. Thus, each minimal turn-on-delay time — at nanosecond level — can be accumulated to be a time span at microsecond or second level and the value is averaged to evaluate the turn-on-delay time.

Pile-plank structures are widely applied for high-speed railway built in soft ground in China. It can be used as a reinforcement to improve the behavior of subgrade by providing vertical confinement to increase their stiffness and strength and reduce the subgrade settlement of ballastless track. However, the use of pile-board structure for soft ground reinforcement of high-speed railway is hindered by the existing gap between applications and theories. To verify vibration characteristics and long-term performance of pile-plank-supported low subgrade of ballastless track and the benefit of pile-board structure, an experimental study was conducted on low subgrade of pile-board under excitation loads using both in situ frequency sweeping and cyclic loading experiments. The frequency sweeping experimental results show that the pile-plank-supported low subgrade has smooth stiffness along the longitudinal subgrade and can effectively control the progressive effects of train speed on dynamic stiffness of the subgrade, which ensures driving safety and comfort. The cycle loading experimental results show that the pile-plank-supported low subgrade has favorable long-term dynamic stability, and its dynamic response is uniform along the longitudinal subgrade.

The feature of deception jamming for GNSS-dot networks is researched and analyzed, and it is difficult to accurately locate and correct the interference position by using the interference detection methods of the traditional WSN, a new attack detection algorithm that based on an improved angle of arrival (AOA) positioning mechanism to determine the point of disruption and interference correction is proposed. Nextly the algorithm of a single interference source localization based on the hyperbolic method by using anti-jamming principle of the GNSS is researched and given, and can locate both single and multiple interference sources. Then the indicators and methods of performance evaluation for the GNSS-dot networks are proposed. Finally, Experiment based on the algorithm is realized, and the attack detection and correction is very efficient, and interference location under ideal conditions is higher efficiency, and the strategies of anti deception jamming are also identified.

The system proposed in this study deals with pedestrian counting and detection in intelligent video surveillance systems. It is a hybrid of map-based and detection-based approaches, and combines the advantages of both. After the foreground objects being segmented, the map-based module, which implicitly compensates the perspective distortion by integrally projecting the features onto a given direction, is triggered to estimate the number of pedestrians in each foreground region. Then, a class-specific Hough forest is employed to locate individuals. Experimental results have validated our strategy. The proposed map-based module has the ability of accurately estimating the count for each region. Also, the estimation can speed up the process of locating individuals by providing cues like the number of targets and the approximate size of each target. The proposed detection-based module not only locates pedestrians, but deals with enhancing the accuracy of the counting as well.

Multi-label learning has received significant attention in the research community over the past few years. Traditional supervised learning techniques do not fit it well, as real-world objects might be complicated and have multiple semantic meanings simultaneously. In our work, we set our goals to mine the involved product attributes in comment data from JD.com. This task is fundamental and significant to businesses for studying the online market feedbacks from consumers. In this paper, we formally define the three types of text categorization problems and analyze the relations among them. Then, we assign some single-label multiclass classifiers to the new training datasets which are created by our constructing algorithms. Thus, multilabel learning is transformed into a series of single-label multi-class binary classification problems: whether an unseen instance belongs to a certain class or not. Finally, we assemble the outputs of all single-label multi-class classifiers to obtain the multiple labels. In the end of this paper, we conducted comprehensive experiments to evaluate the performance of our proposed algorithms.

Global navigation satellite system (GNSS) has been widely used in different fields of transportation, including transportation supervision, security responses, highway construction and administration as well as waterway construction and administration. Over the past 5 years, breakthroughs have been achieved in the typical application fields of BeiDou navigation satellite system (BDS) such as dynamic safety supervision for road transport, vessel monitoring and management and security responses with the growing demands for applying BDS in national demonstration projects. To standardize and improve the quality of GNSS application service in transportation, the Ministry of Transport of the People's Republic of China has established related standards for GNSS applications. However, problems such as too narrow coverage, repeated formulation, varying quality and difficulties in coordination have appeared owing to the lack of top-down designs and plans as the development of the transportation informatization. In this paper, transportation application standard System of BDS is proposed to guide the formulation of BDS application standards in transportation by comprehensively considering the transportation application requirements and a systematic summary of the status of GNSS application standards in transportation.

Performance Simulation for Global Navigation Satellite System (GNSS) that be used for performance simulation and evaluation analysis of the GNSS, is a part of the critical algorithm test and system index analysis for GNSS. In this article, the requirements of GNSS are analyzed firstly, and the characteristic of model portability for GNSS is studied, then the model integration framework based on Simulation Model Portability is proposed. The system architecture consists of model design, development, integrating, executing and analysis. Lastly, the regional performance of GALILEO Navigation Satellite System in China is tested and analyzed based on the integration framework.

The definition for the constellation availability of the navigation system is given firstly, and then calculates the availability of a single satellite by using Markov processes, and establishes the model based on the state probability of the constellation, to achieve mapping model from component reliability of the single satellite to the constellation availability. Finally, we analysis the regional availability performance of the GNSS by the algorithm, which can fit and satisfy the requirements of contradiction between accuracy and rapidity for analysis of availability for constellation of GNSS.

Medium frequency induction heating for large diameter pipe bending is an advanced technique that has been widely used. However, the thickness control of outer wall and inner wall of pipe is still difficult in the actual production: outer wall tends to be thinner and inner wall tends to be thicker. Therefore, it is necessary to optimize the process parameters of bending. Combined central composite experimental design and a proper selection of design parameters sample, an accurate response surface model was built in order to decrease ovality, thickness reduction ratio and forming load. The response value of objective function was analyzed; and important influence factors for system stability were found, i.e heating temperature, heating width and advance speed. The results indicate that the optimal value range were heating temperature of outer wall t=1030∼1070 °C, while advance speed v=0.3∼0.4 mm/sec. Practical results from multi-objective optimization could achieve qualified products.

For ground penetrating radar (GPR), clutter suppression effect has an important role on target detection. Approaches based on minimal entropy, the signal to clutter ratio (SCR) and image contrast are widely used for assessment. These traditional approaches have inevitable defects. Such as, minimum entropy and image contrast methods lead to inaccurate image evaluation under the cases of heavy clutter. SCR method will be influenced by subjective feeling. This paper presents an adaptive SCR evaluation method. This method can evaluate clutter cancellation effect quantitatively without being influenced by subjective factors.

Penetrating radar for detecting near surface target is a kind of radar which can be used to detect, discern and image the small targets buried in the shallow surface of nonmetallic medium. The main clutter of this radar mechanism is the reflection wave transmitted between radar antennas and the surface of the non-metallic medium. If it cannot be reduced, the image of the small targets will be submerged. This paper presents a clutter reduction method which bases on the idea of subdomain mean cancellation to suppress the reflection wave of non-uniform surface of the medium. Experimental results prove that subdomain mean cancellation method can effectively repress the reflection wave of the medium surface and significantly improve the quality of the image.

GPR for detecting shallow surface target has heavy clutter and target echo cannot be distinguished easily. This paper proposes a PCA-SVD mixed clutter suppression method to realize dimension reduction and reconstruction, which can improve the performance of clutter suppression effectively. SVD processing remove direct wave, firstly. Then PCA remove uncancelled clutter and remove noise. At last, we design an experiment to validate the performance of clutter suppression.

This study was conducted to evaluate the adverse health effects on rabbits exposed to SO2 emitted indoors from burning coals, and compare differences between coal-biomass briquette (B.B.) and raw coal (R.C.). Thirty-six male rabbits were divided equally into three groups at random, and then exposed to burning R.C., B.B., and the third without burning coal (Control) for 90 days. Data showed that the average concentration of SO2 in 24 h in R.C. was 13.04 mg m−3, which was 5-fold greater than B.B. (2.68 mg m−3) and 31-fold higher than control (0.41 mg m−3). After 45 days, the numbers of rabbits, with increased frequency of Comet cell was highest in R.C. After 90 days, the % positive Comet cell was significant at 10.36% in R.C., 5.42% in B.B., and 1.73% in Control. There was a nonlinear dose–effect relationship between % positive Comet cell and the concentration of SO2. The incidence of interstitial pneumonia was 6/12 in R.C. and 4/12 in B.B. showing severe squamous metaplasia with atypical hyperplasia in bro...

Fluorescence of Tm3+/Er3+ codoped bismuth-silica (BS) glasses and the sensitization of Ce3+ are investigated. It shows that Ce3+ codoping with Tm3+/Er3+ in BS glasses results in a quenching of Tm3+ ion emission from 3F4 to the 3H6 level. Consequently, the 1.47 μm emission occurs after the population inversion between the 3H4 and 3F4 levels. Furthermore, the codoped glasses show the broad emission spectra over the whole S and C bands with full-width at half-maximum (FWHM) up to about 119 nm, as it combines 1.55 μm emission band of Er3+ with 1.47 μm emission band of Tm3+ under 800 nm excitation.

Raw coal (RC) is the main fuel in many, especially rural parts of China. Biomass briquette (BB), which has less SO2 emission, was developed as a cleaner alternative for RC. In this research, the cooking fuel of a group of countrywomen was switched from RC to BB and studied for health effects. Five biological indices percent of comet cell (COMET), lysozyme saliva (LYS), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) were chosen. All indices were measured three times during the 18-month experiment. Statistical analysis shows that there are significant changes in the indices. Using BB as a cooking fuel improves the function of anti-oxidation system and the nonspecific immune system, and reduces the DNA damage, which is negatively related to LYS and SOD.

Energy efficiency (EE) has become an increasingly important issue in Device-to-Device (D2D) communications since wireless terminals are hand-held equipments with limited battery life. In this paper, an energy-efficient channel reusing scheme for multi-D2D links is proposed. We first analyze the EE of a single D2D link in both non-cooperative mode (NCM) and cooperative mode (CM), and prove that the EE of the D2D link is mainly determined by the location of the cellular user equipment (CUE) that shares resource with the D2D pair. On this basis, a location-based algorithm (LBA) is proposed to select the optimal CUE for each of the D2D pairs, aiming to maximize the sum EE of all D2D links. Numerical results show that the proposed LBA could effectively improve the overall EE of the D2D system while guaranteeing the target rate of each D2D link. Moreover, the proposed LBA does not require the channel state information (CSI) of all the involved links, which could significantly reduce the feedback overhead and computational complexity.

The basic medical insurance system for urban employees that is currently set up in China marks the official formation of a pattern of primary-level medical insurance which requires the shared responsibilities of the state, the work unit, and the individual. This medical-insurance system, established on the "low-level-and-wide-coverage" principle, is a product of the present stage in the economic development of our country. In this system, special considerations are given to retired employees in such areas as the amount of medical costs entered into their personal accounts, the proportion of medical costs to be paid by them, and the amount of self-pay for basic medical insurance. However, its nature as a form of basic medical insurance limits the role it can play in satisfying the medical and health-care needs of the elderly population—a group of people who tend to be weak in health and vulnerable. As we all know, the elderly population has more needs in terms of medical and health care than people of othe...

The ancient Chinese have understood species diversity, ecological diversity and genetic diversity in their long-term labor practice and investigations. Theknowledge was recorded in a great number of historical documents. They have made great contributions to biodiversity protection through developing agriculture and animal husbandry, rational utilizing biological resources, and building various reserves and gardens.

A novel method of codoping the Er3+, Yb3+, and Ho3+ ions in tellurite glasses is demonstrated to obtain a high efficiency of infrared-to-visible upconversion. Three intense emission bands observed in Er3+, Yb3+, and Ho3+ codoped tellurite glasses centred at 525, 547, and 657 nm correspond to Er3+: 2H11/2→4I15/2, Er3+: 4S3/2→4I15/2+Ho3+: 5S2(5F4)→5I8, and Er3+: 4S3/2→4I15/2+Ho3+: 5F5→5I8 transitions, respectively. No visible upconversion quenching phenomenon is observed when three rare-earth ions are codoped together in tellurite glasses. In contrast, the upconversion intensity of red and green emissions in Er3+, Yb3+, and Ho3+ codoped glasses is enhanced largely when compared with Er3+/Yb3+-codoped glasses. The dependence of upconversion intensities on excitation power and the possible upconversion mechanisms are evaluated. The three emissions are based on two-photon absorption processes.

Poly-phenylquinoxaline is used as the electroluminescent(EL) materials to fabricate the thin film electroluminescent devices by the spin coating method. Doped with 1, 3, 5-triphenyl-2-pyrazoline, the EL spectrum of the devices is shifted to the blue-green region with its peak located at 465nm. The incorporation of a hole transport layer, poly-vinylcarbazole, will enhance the EL intensity, and the quantum efficiency is estimated to be 0.2%. Thus, the devices can be driven by either positive or negative bias (or ac voltage) even though the currentvoltage curve possesses a rectifying property.

An Sb delta doping layer in silicon is grown at the temperature of 300°C by silicon molecular beam epitaxy and characterized by the small angle x-ray reflectivity measurement using synchrotron radiation beam. The oscillations of the reflectivity caused by dopant Sb at Q as large as 14.5 are detected. Simulation of this curve as a whole shows that the total amount of dopant Sb is 0.15 monolayer and is restricted to two atomic layers. An extremely narrow Sb delta doping structure without Sb segregation is thus obtained at the growth temperature of 300°C as verified by the experiment.

Porous silicon samples were prepared for optical studies by using the photoluminescence (PL), Raman scattering (RS), as well as the absolute reflectance and ellipsometry methods. Results show that the porous Si has low optic constants, and can trap the visible photons of more than 95%, but give no evidence of a strong interband transition existing in the visible region. The Bruggeman effective-medium-approximation (EMA) and Lorentz oscillator models were used in data analyses. Calculations show that the layer dispersion effect may result in a red shift of the PL peak. The possible mechanism for the PL and Raman enhancement as well as the photon trap phenomenon was discussed, and was attributed mainly to the random multiple micro-reflections in the porous-Si layer having extremely large internal micro-surfaces.

Cognitive Wireless Network (CWN) is a set of heterogeneity networks designed to perceive and learn from current multi-domain environment, then plan and decide a scheme based on the end-to-end goals. It aims to satisfy the integration, ubiquity and broadband requirements of future networks. With the complexity of heterogeneity networks rising, the need to manage this complexity makes the realization of CWN well-timed and attractive. Many related projects to do further study have been built by research teams. During the past few years, we are working on a project called “Basic theory and Key Technologies in Cognitive Wireless Networks”. It is one of the major projects in National Basic Research Program (973 Program) approved by the Chinese government. Our research team concentrates on issues including network architecture, multi-dimension sensing technologies and radio resource management which are connected with each other. In this article, an overview of this project will be shown by introducing its purpose, research vision, research progress, and testbed.

Competition of Sci-Tech novelty retrieval is analyzed at macro-level, meso-level and micro-level. The overview of competition is discussed at macro-level using Five Forces Model. The meso-level is the competition status in view of the Lorenz curve. At micro-level, weighted evaluation model is established to investigate competitive ability of novelty retrieval workstation

It is demonstrated in this paper that the infrared-up-conversion luminescence generation from porous silicon, considered as an enhanced third-order nonlinear optical effect by the recent work, is anisotropic as the polarization vector of normally incident fundamental light is rotated. A new method has been used to determine the anisotropy parameter σ of the third-order nonlinear optical tensor χ(3). Due to the sensitivity of σ to the crystal structure and microscopic electronic properties, the difference in σ's between porous and crystalline silicon, particularly in their phases, demonstrates that the nanometer structure of porous silicon induces a dramatic change of the electronic band structure, but the strongly anisotropic crystal property remains unchanged.

The absorption in Si1-xGex/Si multiple quantum-well structures is measured. Several separated well absorption peaks corresponding to both intersubband and intervalence band transitions in the samples are observed. In the normal incidence, two broadband peaks are attributed to intervalence band transitions HH0-SO0(2.5 µm), HH0-LH0(~3 µm), respectively. Using 45° incidence of unpolarized light, both the intervalence band and intersubband transitions are observed. The intervalence band transitions (HH0-LH0) are Ge composition dependent, but the intersubband transitions, HH0-HH1(5.9 µm) and HH0-HH2(4.3 µm), are not sensitive to the Ge composition.

With the great pressure on employment under current financial crisis, this paper presents hierarchical analysis theory to evaluate the correlation between the configurations of computer major course and employment rate, so as to improve the course configuration and enhance the employment rate. This paper analyzes three provincial colleges with different characteristics, dividing computer major course into four groups. Through different weights on enquiry and scoring by specialists, combining student ability, a comprehensive evaluation model is set up. YAAHP hierarchical analyzing is used to calculate the influence of computer courses on the employment rate, and the result is quite robust. Through empirical training could improve the practical ability and increase the competitive of employment. Maintaining and enhancing specialized course training is closely related to employment rate.