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With the rapid development of food 3D printing technology, its innovative combined application with various auxiliary technologies is attracting more and more attention. Laser technology is characterized by high precision, high energy and rapid material shaping, which matches highly with the personalized customization advantage of food 3D printing technology. The combination of these two techniques shows great application prospects in the field of food processing. This article begins with an introduction to the current development of food 3D printing technology and laser technology, and focuses on the application of laser technology in food 3D printing from the perspectives of laser parameters (such as wavelength, power and pulse) and processing advantages. At the same time, this article points out the challenges facing the application of laser technology in food 3D printing, such as food safety and application limitations. Finally, this article summarizes trends in the deep integration of laser technology and food 3D printing technology and points out future directions so as to provide a theoretical basis for the innovative application of laser technology in the field of food 3D printing.

5G serves as the pivotal infrastructure for the emerging era of the Internet of everything, with intelligentization being its crucial direction. In the 5G-Advanced (5G-A) phase, AI enabled core network running can substantially enhance network efficiency, facilitate real-time perception, and precisely cater to diversified service demands through the deep integration of AI technology and network running mechanisms. For the 5G-A network, the overall intelligent architecture, key technologies, and applications of AI enabled core network operations were highlighted. Firstly, the development trend of AI enabled 5G-A core network running was analyzed and key intelligent applications were elaborated. Secondly, AI enabled core network running architecture combining four layers and four dimensions was proposed, encompassing a central intelligent analysis layer, a control plane intelligent endogenous layer, an edge real-time inference layer, and an on-device lightweight inference layer. This architecture enables customized, real-time data collection across four dimensions: slices, network elements, users, and service flows, thereby offering intelligent analysis services such as data perception, training, and inference. Then, five key technologies and capabilities of AI enabled core network running were introduced. Finally, focusing on the typical service requirements of AI enabled core network running, the relevant solutions and their results were analyzed and summarized, thus providing new ideas for the application and implementation of 5G-A core network intelligence.

This study investigated the effects and evaluation indicators of air conditioning temperature control for summer storage of wheat in large flat storage silos. In the second and third years after wheat was stored in Silo No. 19 of Luliang Jituan Pingyuan Grain Storage Depot, the air conditioning was set to 25 ℃, and the conditions were compared with those in the control Silo No. 17. The temperatures at the surface, second layer, third layer, and fourth layer of the grain bulk were reduced by 3.4 ℃, 2 ℃, 1.5 ℃, and 1.35 ℃, respectively. The moisture content, relative humidity (RH), and wet-bulb temperature were reduced by 3.85 g/kg and 1.5 g/kg, 3.55% and 3.85%, and 3.65 ℃ and 2.2 ℃ for the surface grain and the entire grain bulk, respectively. No significant differences were observed in the thermal characteristic parameters of the grain bulks in the two silos. Compared with Silo No. 17, the peak viscosity, breakdown, and final viscosity of wheat in Silo No. 19 slightly decreased, and the texture parameters, such as hardness, adhesiveness, springiness, gumminess, and chewiness, also slightly decreased. Principal component analysis identified the gelatinization end temperature and peak height measured by DSC, the gelatinization temperature and peak time measured by RVA, and texture parameters such as hardness, gumminess, and chewiness as preferred indicators for evaluating the summer storage of wheat under temperature control. In-depth scanning electron microscopy analysis revealed that the cross-sections of wheat kernels in Silo No. 19 were more compact with uniformly distributed micropores, and the longitudinal sections had fewer small starch granules between large starch granules compared to those in Silo No. 17. The results indicated that operating air conditioning in large flat storage silos during summer helped reduce the dry-bulb temperature of the grain bulk and the air characteristics in the interstitial space between kernels. It also slowed the growth and development of storage pests, and maintained the microstructure of wheat kernels, which could delay quality deterioration.

Conventional nuclear magnetic resonance (NMR) instruments are large and difficult to carry, which limits their application in fields such as on-site petroleum exploration, food safety, environmental pollution, and quality control. To address this issue, this paper proposes a design of a handheld NMR console. By utilizing an advanced RISC machine (ARM) core construction, field programmable gate array (FPGA) logic design and control program design on a programmable system-on-chip Zynq-7000, the entire handheld NMR console was designed and implemented. After completing the entire design, several basic pulse sequences, including free induction decay (FID), spin echo (SE), and Carr-Purcel1-Meiboom-Gill (CPMG), were tested on a 0.5 T desktop NMR system developed by our research group. The tests validated the correctness of the overall architecture design and the coordination among various modules. The designed NMR console is 10.6 cm long, 6.0 cm wide, and 1.9 cm high, which significantly reduces the size while enhancing the real-time performance of pulse sequence and improving the stability of the console, laying a foundation for further development of portable NMR instruments.

To improve the physicochemical properties and processing performance of black wheat flour dough, the effects of adding Glucose oxidase (GOD) on the gelatinization, thermomechanics dough tensile, rheology properties, and microstructure of black wheat flour were investigated using a rapid viscosity analyzer, a texture analyzer, and a scanning electron microscope, among other methods. The effects were also explained in terms of changes in protein fractions. The results showed that the moderate addition of GOD could significantly reduce the content of free sulfhydryl groups and increase the content of disulfide bonds in the dough of black wheat flour, thereby enhancing the degree of protein cross-linking and significantly improving the physicochemical properties of black wheat flour dough. The best improvement in dough structure and properties was achieved when the GOD addition was 0.8%, at which point the ratio of wheat alcohol-soluble protein to wheat gluten (0.81) was close to the optimal ratio (1.0). This study has provided a certain reference for the development of black wheat-based foods and the improvement of their edible quality.

With the realization of “Space 180”, as well as the proposal of the “Space Home Port” program and the manned Mars exploration program, taikonaunts have gradually undertaken more long-term missions in deep space. Therefore, the supply technology of space foods is facing new challenges. Three-dimensional printing technology, also known as additive manufacturing technology, provides a new idea to solve space food problems because of its ability to produce highly customized and personalized foods. Through research and analysis, this article introduces common 3D food printing methods, systematically discusses the application of 3D printing technology in the design and production of space food shapes and the regulation of nutrients and flavor as well as its advantages in enabling the long-term storage and transportation of space foods, and points out the unique challenges of 3D printed food production in the space environment, including printing and shaping under microgravity conditions, and the impact of cosmic radiation on materials and equipment. Finally, an outlook on future trends and directions for 3D printed space food technology is provided, aiming to provide a reference for space food innovation.

[Objective] Water scarcity has become a major constraint to the development of grassland regions. From the perspective of herders, exploring the value of grassland water resources and attempting to establish a feasible pricing scheme for irrigation services is of great significance in promoting the realization of the value of grassland water resources. [Methods] Using survey data from pastoral areas of Inner Mongolia in 2021, this study employed the choice experiment method to simulate irrigation services, applied the random parameters logit regression model to analyze and estimate the value of grassland water resources, and conducted a cost-benefit analysis. [Results] (1) From the herders’ perspective, the value of water resources reaches 0.130 Yuan/m3 in the desert grassland areas, 1.366 Yuan/m3 in the typical grassland areas, and around 0.640 Yuan/m3 in the meadow grassland areas; (2) Herders are willing to pay for grassland irrigation services to improve their water scarce situation. They have differential preferences for different service providers and demonstrate a stronger preference for irrigation services provided by the government and agricultural enterprises compared to village committees. The increase in irrigation frequency can significantly improve herders’ well-being. Heterogeneity analysis indicated that herders with smaller land management area are more inclined to purchase paid irrigation services and prefer higher frequency irrigation services; (3) The fee scheme for grassland irrigation services and the results of cost-benefit analysis indicate that the cost of providing grassland irrigation services is much lower than the subjective benefits obtained by herders. (4) Taking the provision of artificial rainmaking technology as an example, herders in Inner Mongolia can obtain an annual consumer surplus of approximately 1.031 billion Yuan by purchasing irrigation services. [Conclusion] Different types of grasslands significantly influence the value of water resources. Furthermore, herders have a real demand for paid irrigation services to reduce the scarcity of grassland water resources, increasing the frequency of irrigation can enhance herders’ utility, and the government and agricultural enterprises play an important role in providing irrigation services. Finally, providing irrigation services is economically viable, and the value of grassland water resources can be realized through the provision of paid grassland irrigation services.

Objective: To obtain a lightweight Mini-Alexnet banana ripeness grading model and apply it to Android mobile devices. Methods: Based on the external characteristics of bananas with different ripeness, the Alexnet network model was restructured, part of the convolutional layer was deleted, and the global average pooling was used instead of the full connection layer to reduce the model parameters and required memory. A larger convolutional kernel was replaced to extract the global characteristics of the banana skin to achieve an improved lightweight Mini-Alexnet network model. Then the Mini-Alexnet network model was deployed as Android mobile APP, and its feasibility and practicability were verified. Results: The Mini-Alexnet model was only 11.6 MB, and the identification accuracy rate of banana ripeness level 5 was 97.76%. The accuracy rate of local picture recognition mode, photo recognition mode and real-time recognition mode of the mobile APP banana ripeness automatic identification system was 86.66%, 79.33% and 74.00%, respectively, with an average accuracy rate of 80%. Conclusion: The improved Mini-Alexnet model occupies less memory space.

In the context of the “dual carbon” goals， photovoltaic energy storage charging stations （PSCSs） are gradually emerging as the mainstream form of electric vehicle （EV） charging stations. To address the uncertainty associated with photovoltaic （PV） generation and user charging behavior， while ensuring the profitability of PSCSs， the paper proposes a method for optimal allocation of energy storage capacity for PSCSs that takes account of EV user behavior and PV uncertainty. Firstly， an improved K-means algorithm is employed to cluster PV output data， establishing typical PV output scenarios and their rules of probability distribution. Secondly， the charging behavior characteristics of EVs are analyzed， incorporating the impact of environmental temperature variations on EV power consumption to develop an EV charging load model. Lastly， considering demand response， an economic operational model is formulated with the objective functions including purchasing cost， carbon emission cost， and electricity sales revenue. Case study results demonstrate that incorporating PV output uncertainty and demand response during energy storage capacity configuration of PSCSs can reduce carbon emissions and ensure the economic viability of PSCSs.

Cereal foods are the primary source of daily energy, protein, and dietary fiber intake for humans. With the continuous improvement of people's living standards, cereal foods' nutritional value, safety, and food quality have attracted much attention. Cereal metabonomics, as a new and rapidly developing branch of "metabonomics", has made rapid progress in quantifying and analyzing various metabolites. This article reviews the analysis process of metabolomics technology, and its application in the detection of component identification, the identification of flavor substances, the traceability of origin, and the product of new developments in cereal foods, and the development trend of metabonomics in cereal food field has prospected, to provide a reference for the in-depth development and application of cereal foods.

Since 2017, human encephalitis caused by pseudorabies virus (PRV) has been reported in 28 cases in China. The clinical symptoms include fever, headache, seizures, focal neurological loss, disturbance of consciousness, etc.. This disease has the high disability rate and fatality rate. PRV is mainly transmitted through close contact with infected pigs or their excrement, or spread via blood-borne. Patients are mostly practitioners in the live pig industry chain. Early diagnosis and treatment are critical to the prognosis of patients. Therefore, this article reviews the progress on diagnosis and treatment of human encephalitis caused by PRV, in order to improve the clinical diagnosis and treatment of this disease.

In the remote operation and maintenance of relay protection, there are network intrusion risks at every stage of data transmission. Existing security measures have not effectively addressed business layer risks, and some issues such as delayed risk response still exist. Therefore, a message compliance detection method and intrusion blocking technology have been proposed. By analyzing the objects, formats, business logic, and behavioral patterns of messages, a library of message compliance rules and a strategy for blocking non-compliant messages are established. Finally, modules for blocking non-compliant messages and an "emergency blocking" control module are designed and developed. The simulation testing results indicate that the proposed technology consistently blocks abnormal messages of different types as expected. This technology can effectively prevent the illegal intrusion attacks, thereby enhancing the security and stability of the remote operation and maintenance for relay protection.

To understand the cause for the increasing water absorption rate of wheat shorts after cold plasma treatment, a dynamic moisture adsorption instrument was used to measure the moisture sorption isotherms of samples treated with 120 W low-pressure strong radio frequency helium or oxygen CP for different times. The result was that the Caurie equation can fit an isotherm, and its coefficient C0 gived the density of water adsorbed by the sample. For adsorbed or desorbed samples, as the helium or oxygen CP treatment time at the same power increased, there was no difference in the density of adsorbed water, and the coefficient M0 gived the adsorbed water content of the monomolecular layer of the sample. For adsorbed or desorbed samples, as the helium CP treatment time at the same power increased, the water content of the monomolecular layer increased significantly. For samples treated with oxygen plasma, the content of the adsorbed monomolecular layer water first decreased and then increased as the treatment time increased, while the desorbed single-molecule water content showed a decreasing trend with the increased time. In order to improve the fitting of the Caurie equation, M0 was corrected to A+Bt (t was the temperature, A and B were constants). Analysis of the coefficients of the modified Caurie equation showed that as the 120 W helium CP treatment time (0~180 s) increased, the monomolecular layer of water, the number of adsorbed water molecule layers, the bound water content, and the water adsorption surface area all showed a continuous increase trend. For oxygen CP, these indicators showed an increasing trend in the first 60 s of processing, and then showed a decreasing trend if the processing time was extended. The results showed that compared with oxygen-cold plasma, high-energy helium-cold plasma improved the hydrophilicity of wheat shorts proteins and polysaccharides. As the treatment time increased, the surface area and number of layers of water adsorbed by these macromolecules and the monomolecular layer, and the bound water content steadily continued to increase.

Vestibular evoked myogenic potentials (VEMPs), a key electrophysiological technique, is extensively utilized for the clinical evaluation of vestibular function. Patients with Parkinson's disease (PD) often have vestibular dysfunction, with VEMPs abnormalities being the most common. Based on the brief introduction of VEMPs technique, this review summarizes the features of VEMPs abnormalities, its association with clinical phenotype and underlying pathophysiological basis in patients with PD, so as to provide guidance for clinical research and practical application.

[Introduction] In order to analyze the influence of atmospheric stability on the output of wind turbines, and to provide technical reference for improving the simulation accuracy of CFD wind energy resources. [Method] Based on the observation data of different heights of two wind towers in flat and complex mountainous terrain, including wind speed, air temperature, air pressure and other data of multi-layer height, the atmospheric stability of the two wind towers in the region was calculated by using the Moning-Obkhov length method, and the stability calculation results were classified according to Irwin atmospheric stability classification standard. [Result] The results show that: in the near surface layer, the vertical mixing effect caused by the atmospheric thermal effect in complex mountain area is more obvious, and the atmospheric instability is stronger, but the vertical mixing effect is not sufficient; The impact of atmospheric stability on wind turbine output in complex mountainous area is greater than that in flat terrain, and its uncertainty is higher. The reason largely depends on the complexity of atmospheric stability, so it is more necessary to consider the impact of atmospheric stability in wind energy resource assessment. [Conclusion] It is necessary to consider the influence of atmospheric stability in CFD wind farm fluid modeling, especially under the condition of ultra-low wind speed complex mountain site, the evaluation of atmospheric stability is particularly important for fan selection and power generation simulation accuracy.

ObjectiveTo investigate the high-risk detection rate and aggregation of cardiovascular diseases（CVD） in 8 districts of Shanghai and influencing factors， and to provide scientific references for prevention and control of CVD.MethodsBased on the Cardiovascular Disease Screening and Management Program in Shanghai from 2016 to 2021， 104 685 participants aged 35 to 75 in 8 districts of Shanghai were selected for analysis. χ2 test and multivariate logistic regression were used for statistical analysis of the influencing factors of CVD and aggregation of CVD.ResultsThe proportion of high-risk CVD individuals in the population was 19.17%， including the high-risk individuals with hypertension （8.65%）， dyslipidemia （6.33%）， CVD history （5.58%）， and WHO assessed risk ≥20% types （2.69%）， respectively. Old age， overweight and obesity， central obesity， smoking， drinking， farmers， unmarried， and low family income were the risk factors of CVD， while high education level was the protective factor. In the participants， 16 323 people （81.34%） were classified as CVD high-risk groups； The number of aggregation of 1， 2 and ≥3 high risk types of CVD were 16 323（81.34%）， 3 236（16.13%）， 509（2.54%）， respectively. Old age， low education level， low annual family income， farmers， unmarried， smoking， drinking， overweight， obesity and central obesity were associated with the risk of aggregation of high risk types of CVD， and the correlation strength increased with the increase of aggregation types.ConclusionThe prevention and control of CVD in Shanghai should focus on the hypertension， elderly， overweight， obesity， central obesity， smoking， drinking， low educated， low family income， farmers and unmarried people， and targeted intervention measures should be taken to reduce the risk of CVD among residents.

Functional tics is one type of functional movement disorders (FMD) with overlapping clinical manifestations of primary tics. It is difficult to distinguish them in clinical practice. In this text, we will introduce the epidemiology, risk factors, clinical features, diagnosis and treatment of functional tics by comparing with primary tics (especially Tourette's syndrome), with the aim to improve the rate of accurate diagnosis, and avoid misdiagnosis and mistreatment.

[Objective] Time preference is the psychological preferences of actors about the current and future utility in cross-decision making. The preference for “current utility” or “future utility” of pesticides is essential for bio-pesticide adoption. [Methods] Based on the experimental data of farmers in Sichuan Province in 2021, this study analyzed the impact of time preference on the willingness of farmers to adopt bio-pesticides, and further examined the moderating effect of extension approaches on time preference. [Results] The results show that: (1) Time preference significantly weakened the willingness of farmers to adopt bio-pesticides, and farmers who pay high attention to “current utility” always showed lower willingness. (2) The moderating effect suggests that agricultural technology extension measures, such as the establishment of demonstration bases for green pest control technologies, could inhibit the negative impact of time preference on farmers’ willingness to adopt bio-pesticides. For farmers with different levels of literacy，the moderating effect of extension services was heterogeneous. Free distribution of biopesticide products had a more obvious positive effect on farmers with high educational level, while technical training had a more obvious positive effect on farmers with low educational level. [Conclusion] The high time preference of farmers leads to a preference for the “current utility” of pesticides, resulting in a lack of willingness to adopt biopesticides. Agricultural technology extension can effectively mitigate the adverse effects of high time preference, but attention should be paid to adopting differentiated extension methods for farmers with different levels of education.

In the process of deep geological disposal of high-level radioactive waste, the strong radiation field caused by the decay of radionuclides can lead to the leaching property changes of the waste glass. In this work, the 15 MeV Si ion irradiation was used to simulate the strong radiation field of deep geological disposal. The samples were immersed for 1, 3, 7, 14, and 28 days in KOH solution with pH=9.0 by using the MCC-1 method, respectively. The leaching behavior of the borosilicate glass before and after irradiation was studied by inductively coupled plasma emission spectrometer, Raman spectrometer and scanning electron microscope. It is observed that the leached glass surfaces occur constantly corrode and fall off with the increase of leaching time. The leaching rate of the irradiated glass samples is significantly higher than that of the unirradiated glass samples. Although it is observed that the thickness of altered layer is increased after irradiation, there are no significant difference in the structure and element composition of the altered layer between the unirradiated glass and the irradiated glass. The sodium and boron elements in the formed altered layer are basically depleted. The SiO2 network structure in the altered layer is dissolved, a large number of Si—OH bonds and borosilicate structures are created, and the transformation from four-coordinated boron units to three-coordinated boron units is also observed.

Acute myocardial infarction (AMI) is an ischemic myocardial necrosis caused by coronary artery occlusion, which can't be self-repaired through cardiomyocyte regeneration. The necrotic myocardium is replaced by fibrous scars during ventricular remodeling, ultimately leading to heart failure. The safety and efficacy of mesenchymal stem cells (MSCs) transplantation after AMI have been demonstrated by numerous preclinical and clinical studies. MSCs are composed of heterogeneous cells with multi-directional differentiation potential, which can regulate oxidative stress, and secrete a variety of cytokines and growth factors. After being implanted in vivo, MSCs play their roles in immunomodulatory, angiogenesis, anti-inflammatory, and anti-apoptosis through trans-differentiation, cell fusion, and paracrine. Currently, there has been a variety of access to implant MSCs, including intramyocardial injection, intracoronary infusion, and intravenous injection. In addition, the dose and timing of transplantation are also important factors affecting the therapeutic effect of MSCs. However, the low retention and survival rates of MSCs in infarcted myocardium after being transplanted limit their further effect and hinder their clinical translation. In recent years, new concepts, strategies, technologies, and methods for MSCs treatment have been proposed, including cell preconditioning, optimization of the infract local microenvironment, combined gene therapy or tissue engineering technology, exosome infusion, and targeted transplantation of stem cells and their exosomes, which significantly improve the transplantation efficiency and therapeutic effect of MSCs, and open a new chapter for the research and transformation of stem cells to repair the infarcted myocardium. This article reviews the progress of MSCs in repairing myocardial infarction in recent years.

Food material is the key factor of food 3D printing. This review summarized the characteristics of food materials (protein, starch, hydrogel and fat) commonly used in food 3D printing at present, analyzed the influence of different material combinations on the forming performance. Moreover, suggestions on how to improve the printing effect of difficult printing materials were also provided, and the technical bottleneck of food materials development faced in food 3D printing nowadays were noticed. Finally, the direction of food 3D printing technology in the future was prospected.

The magnet of permanent magnet magnetic resonance instrument is susceptible to the interference of temperature and other environmental magnetic fields, resulting in fluctuations of the main magnetic field, which affects the repeatability and accuracy of the measurement. In this paper, two locking methods to solve the magnetic field fluctuation are discussed. On the one hand, the transient magnetic field caused by environmental fluctuation is detected by fluxgate sensor with high sensitivity, and then the field programmable gate array is used for real-time processing and calculation of the magnetic field compensation. On the other hand, the time-domain digital frequency discrimination locking method is employed for the slow magnetic field drift caused by changes in ambient temperature. After the locked sample being excited by radio frequency, nuclear magnetic resonance (NMR) signal is converted to a lower frequency range through frequency mixing, converted into a square wave signal, and directly sent to the field programmable gate array for periodic measurement. The magnetic field compensation amount is also obtained by calculation. The magnetic field compensation obtained by the two methods is superimposed, and then converted into current signal to drive B0 compensation coil mounted on the magnet, thereby a magnetic field locking system is developed to realize the locking of the magnetic field. The test is carried out on a 0.5 T food rapid detection magnetic resonance analyzer. When subjected to transient interference, the magnetic field can be stabilized within the range of ±4 Hz (corresponding to ±0.093 9 μT), and the magnetic field drift caused by temperature can also be accurately measured, which verifies the feasibility of the magnetic field locking method presented in this paper.

Objective To analyze the effect of transitional care on the self-management ability and negative emotion of discharged patients with differentiated thyroid cancer treated with 131I therapy. Methods A total of 120 patients with differentiated thyroid cancer treated with 131I therapy were selected. Participants were randomly assigned to either the intervention (n=60) or control group (n = 60). The control group was given routine nursing care, and the intervention group received transitional care based on routine nursing care. The self-management ability and negative emotions of the two groups of patients after intervention were compared. Results After intervention, the total score of self-management ability in the intervention group (9. 00 ± 0. 78) was significantly higher than that in the control group (6. 52 ± 0. 77), and the difference was statistically significant (t = 24. 877, P < 0. 01). After intervention, the Self-Rating Anxiety Scale and Self-Rating Depression Scale scores of the intervention group were lower than those of the control group, with a significant difference(P

Objective: To classify banana ripeness quickly and accurately. Methods: Collect the bananas images of different maturity and establish gallery, using a variety of different neural networks as a classifier, banana feature extracting by migration study classifying banana six maturity level, access to the most suitable for banana maturity classification network model, network model, based on the improved and easily banana maturity real-time detection interface design, Finally, the feasibility and practicability of the model were verified. Results: AlexNet model was most suitable for banana maturity classification with the highest accuracy of 95.56%. AlexNet model was improved by modifying its full-connection layer structure, and the model accuracy was further improved by 1.11%. Conclusion: AlexNet model can quickly and accurately identify and classify bananas of different maturity.

The rapid development of artificial intelligence (AI) has brought new opportunities for cancer prevention and control. This review give a brief overview of the origin and basic elements of AI. Then it comprehensively carded the application of AI systems in the field of cancer, reviewed the important research progress of AI in several major types of cancer around image-based cancer screening and diagnosis. Finally, this review summarized the challenges in algorithm, implementation and ethics and future development as well as more ideas for the application of AI technology in the oncological research.

Objective To understand the epidemiological characteristics of public health emergencies in Qinghai Province from 2009 to 2023, providing a basis for decision-making in the prevention and control of such events. Methods Data on incidents from 2009 to 2023 in Qinghai Province were collected and organized from the "Public Health Emergency Report Management Information System". Descriptive epidemiological methods were used to analyze the characteristics of these incidents. Results A total of 311 public health emergencies were reported in Qinghai Province from 2009 to 2023, with 9 099 cases of illness affecting a total of 480 213 individuals, resulting in 46 deaths. Join point analysis revealed a turning point in infectious disease incidents, with a statistically significant upward trend from 2012 to 2023 (P=0.001). In contrast, non-infectious disease incidents exhibited a notable downward trend, with an annual percentage change (APC) of -8.30% (95%C7: -14.91% to -2.86%, P=0.003). Global spatial autocorrelation results indicated that, except for 2015 when public health emergencies in Qinghai showed a spatial negative correlation (Moran's I-0.321, Z=-1.557, P=0.035), no statistical differences were observed in other years (P>0.05). Pearson correlation analysis revealed a positive correlation between the reporting time of incidents and the duration of infectious disease outbreaks (r=0.43, P<0.05), indicating that longer reporting intervals were associated with longer outbreak durations. Conclusion There is a correlation between incident reporting and outbreak duration in Qinghai Province. It is recommended to enhance the awareness of timely reporting among medical institutions at all levels and to strengthen epidemic monitoring in key gathering places, such as primary schools, to reduce the occurrence of public health emergencies. [ABSTRACT FROM AUTHOR]

The water environment of Shenzhen Bay,one of the key waters in the Guangdong-Hong Kong-Macao Greater Bay Area,is mainly influenced by the urbanization of the surrounding areas.Water resource protection and water environment governance are particularly important for Shenzhen,a water-deficient city.This paper explores the specific influence relationship between each factor and the water environment in the process of urbanization.The comprehensive water pollution index and Pearson correlation analysis are utilized to analyze the relationship of the changes in population size and industrial structure with the water environment of Shenzhen Bay in urbanization.The research shows that the main pollutants in the water environment of Shenzhen Bay are chemical oxygen demand (COD) and ammonia nitrogen (NH3-N),and some pollutants come from urban non-point source pollution.The water quality in Nanshan District is good,while that in Futian District is poor,but the overall water quality shows a trend of improvement.The water environment is less affected by population change and more affected by industrial structure change.Therefore,formulating reasonable policies to guide the transformation of the industrial structure is an effective way to improve the water environment of Shenzhen Bay.

Based on the development and distribution of cracks, we explored the shear performance of concrete beams without web reinforcement under different shear span ratios and longitudinal reinforcement ratios. Nine groups of concrete beams without web reinforcement with shear-span ratios of 1.5, 2, 2.5 and longitudinal reinforcement ratios of 1.28%, 1.62%, and 1.99% were used for four-point loading shear tests. The cracks on the surface of the test beam were analyzed by applying fractal geometry theory, and the box counting method was used to calculate the fractal dimension of the cracks on the surface of the beam under the effect of the graded load and the ultimate load. The relationship among the fractal dimension of the beam surface, the ultimate load, the graded load and the span was discussed. The results show that the shear-span ratio is inversely proportional to the ultimate load and cracking load, while the longitudinal reinforcement ratio is directly proportional to the ultimate load and exhibit a small influence on the cracking load. Concrete beams without web reinforcement have obvious fractal characteristics under the effect of graded loading or ultimate load. The fractal dimension under the effect of graded load is 0.964–1.449, and the fractal dimension under the effect of ultimate load is around 1.33. The graded load, mid-span deflection and fractal dimension show a good logarithmic relationship. The change curve of graded load and fractal dimension is affected by the shear-span ratio and the beam longitudinal reinforcement ratio. The intermediate deflection is less affected by the shear-span ratio. Under the effect of the longitudinal reinforcement ratio, the curvature of the curve shows a trend of first increasing and then decreasing, but the relationship between the ultimate load and the fractal dimension has certain differences. The ultimate load first increases and then decreases with the increase of the shear span ratio, and the difference is greater with the increase of the longitudinal reinforcement ratio.

Objective: To establish an analytical method for the determination of four main flavor substances in liquor. Methods: A gas chromatography mass spectrometry （GC-MS） method was established for the simultaneous determination of esters, alcohols, acids, and aldehydes in liquor. Single ion monitoring （SIM） mode was chosen. Then the method was inspected through comparison with the standard mass spectrum database, quantitative analysis of the external standard method and relative standard deviation of day-in and day-out were investigated. Results: The limits of detection of the four types of flavor compounds in liquor were 0.007~0.070 mg/L, and the limits of quantitation were 0.020~0.200 mg/L, and the linearities were satisfactory in the range of 0.000 5~5.0 g/L, with the correlation coefficients of R2≥0.998 5. The accuracy was tested by adding three levels of low, medium and high concentrations of standard substances to ethanol in water （60%）, and the average recoveries of the four categories of flavor substances were 87.8%~107.4%, with the relative standard deviations （RSDs） of 2.0%~7.4% （n=6）. Conclusion: The method is accurate and reliable, with good repeatability and high sensitivity. The method is stable and can be used for the determination of various trace substances in wine. It was found that the volatile flavor compounds of different flavor liquors were different to some extent, which could provide a reference for further research on the flavor compounds of liquor.

The approved health food products in China were analyzed from the following five aspects: the number of approved products, the use of raw materials, the claim of health function, the distribution of dosage forms, and the index of signature ingredients. It was found that almost all Spirulina powder was the primary processed product, and the homogeneity was serious. Moreover, the characteristic components were different from those of β-carotene and phycocyanin specified in the record. Based on these problems, the healthy development of health food industry should be promoted by broadening the idea of product research and development, and then improve the synergistic effect of registration and filing.

Objective To analyze the secular trends of pancreatic cancer incidence and mortality in Changning district of Shanghai from 1974 to 2013. Methods We calculated the age-standardized rates of incidence and mortality and the average annual percent changes for pancreatic cancer using Segi's world standard population and the data from Shanghai Cancer Registry. Age-period-cohort model was constructed to further assess the effect of age, diagnosis period and birth cohort on the secular trends of pancreatic cancer incidence and mortality. Results During 1974-2013, the age-standardized incidence and mortality rates were 6.49/105 and 6.01/105 in male, 4.83/105 and 4.57/105 in female, respectively. The age-standardized incidence was increased by 0.8% per year in male during past 40 years, while there was no change in mortality. The age-standardized incidence and mortality rates were increased by 1.6% and 1.3% per year in female. After adjusting the effects of diagnosis period and birth cohort, the incidence and mortality rates of pancreatic cancer increased by about 11% every 5 years older in both male and female. Diagnosis period and birth cohort had no statistical impact on the incidence and mortality of pancreatic cancer. Conclusion The age-standardized incidence of pancreatic cancer shows significantly rising trends during 1974-2013 in both male and female in Changning district of Shanghai, as well as the age-standardized mortality in female. The incidence and mortality rates also increase with age.

The performance of lithium-ion batteries is greatly affected by the temperature change. Therefore, it is of great significance to get the temperature information to develop the thermal management system. In order to solve the problem that the local temperature caused by the traditional temperature sensor arrangement cannot replace the overall average temperature, it is necessary to conduct studies of average temperature estimation for 10 A·h ternary nicke clobalt manganese lithium-ion batteries at variable environment temperature. First, a lithium-ion battery is modeled and the experimental platform is built to obtain the parameters which are necessary for modeling. Then, an average temperature estimation method for lithium-ion batteries based on recursive least squares and the extended Kalman filter algorithm is proposed. Finally, to verify the effectiveness of the proposed method, the experimental data of the battery at variable environment temperature is obtained under improved hybrid pulse power characteristic (IHPPC). The results show that the proposed method can estimate the average temperature of lithium-ion batteries in real time. The maximum error of the temperature estimation model after the algorithm convergence is 1.8 ℃, and the average error is only 1 ℃.

ObjectiveTo investigate the prevalence and risk factors of injury among both primary and middle school students in Changning District， Shanghai， and to provide evidence for injury prevention.MethodsIn 2018， data of basic characteristics and injury-related factors were obtained through field questionnaire survey among the selected primary and middle schools （2 of each）.ResultsThe study finally included 1 821 students， with injury incidence rate of 30.1%. Among them， the injury incidence rate for the primary schools was 32.0%， and 28.8% for the middle schools. The top three injury types were falls， sharps injuries， and blunt injuries. Age， gender， myopia， and injury-related knowledge/behaviors were significantly related to injury incidence.ConclusionFalls should still be the priority of injury prevention for primary/middle school students in Changning District. The effect of reducing injuries can be achieved by improving health education about injury-related knowledge/behaviors.

Long-term continuous cropping, excessive nitrogen input, and low nitrogen use efficiency are prevalent issues in wheat production in the Northwest Oasis irrigation area. This study examined the compensatory mechanism on grain yield and nitrogen utilization by reducing nitrogen input in wheat and multi-cropping of green manure after wheat harvest. The goal was to provide a theoretical basis for developing efficient wheat production technologies with reduced nitrogen input. This long-term field experiment, initiated in 2018, collected data from 2020 to 2022. The main plot included four green manures: multi-cropped common vetch mixed with hairy vetch (HCV), common vetch (CV), rapeseed (R), and fallow (F) after the previous wheat harvest. Subplots applied three nitrogen rates: the local conventional rate (N3, 180 kg hm-2), reduced by 20% (N2, 144 kg hm-2), and reduced by 40% (N1, 108 kg hm-2). Our results indicated that reducing conventional nitrogen by 20% and 40% significantly decreased both grain yield and nitrogen uptake. However, multi-cropped hairy vetch mixed with common vetch after wheat harvest could compensate for the yield and nitrogen uptake losses caused by a 40% nitrogen reduction. When combined with a 20% nitrogen reduction, grain yield and nitrogen uptake increased by 21.4% and 6.9%, respectively (P < 0.05). Additionally, this cropping pattern compensated for the decreased nitrogen use efficiency resulting from a 40% nitrogen reduction and, when combined with a 20% nitrogen reduction, enhanced nitrogen use efficiency by 13.4% (P < 0.05). The compensation mechanism was attributed to: (1) Under a 40% nitrogen reduction, multi-cropped hairy vetch mixed with common vetch compensated for nitrogen uptake rate, increased net nitrogen assimilation rate by 34.3% (P < 0.05), maintained nitrogen distribution in the ear, and enhanced the nitrogen transportation rate from the stem by 6.6% (P < 0.05). (2) Compared with fallow after wheat harvest and the conventional nitrogen application rate, multi-cropped hairy vetch mixed with common vetch under a 20% nitrogen reduction increased mean nitrogen uptake efficiency and net nitrogen assimilation rate by 7.2% and 34.1%, respectively (P < 0.05). It also improved nitrogen distribution in the ear from early filling to maturity stages by 6.7% (P < 0.05) and enhanced the contribution rate of nitrogen transportation from stem and leaf to ear by 17.8% and 8.9%, respectively (P < 0.05). Therefore, multi-cropped hairy vetch mixed with common vetch after wheat harvest is a viable measure to reduce nitrogen fertilizer input. When combined with a 20% nitrogen reduction, it can increase grain yield and nitrogen use efficiency in wheat by improving nitrogen uptake rate, net nitrogen assimilation rate, and the contribution rate of nitrogen transportation from leaf and stem to ear, thereby promoting nitrogen distribution in the ear in arid oasis irrigated areas. [ABSTRACT FROM AUTHOR]

Objective This study aims to investigate the current situation of ultrasonographic teaching and learning needs from eight-year program undergraduates in Peking Union Medical College. Methods Questionnaires of the current situation about ultrasonographic teaching and learning needs from students were collected and compared with feedbacks from students from 4+4 pilot project curriculum who received a new pattern of ultrasonographic teaching. Results The students of eight-year program showed weakness in understanding of definition and development of ultrasound discipline, basic knowledge and ultrasonographic technology. They were not satisfied with the current ultrasonographic teaching and hoped to improve the curriculum content and teaching pathway. Conclusions Based on these results, the ultrasonographic curriculum design and teaching patterns should be adjusted according to students' demands and emphasize essential and basic knowledge such as ultrasonographic manifestations of normal human anatomy and that found in common diseases.

Objective To establish a simple and convenient early warning scoring system by retrospectively analyzing the high risk factors of early intracranial hemorrhage (ICH) in acute non-promyelocytic leukemia (ANPL) patients. Methods We enrolled 1281 adult patients with ANPL (model group) and 378 adult patients (validation group), all patients were followed up for 12 months respectively. We used the data of model group to summarize the relevant factors of ICH occurrence and established risk scoring system. The risk scoring system was validated by the data of the validation group (each patient in the validation group was scored by the scoring system and divided into high, medium and low risks groups). The prediction efficiency of the scoring system was evaluated by ROC curves. Results Univariate and multivariate analyses showed that the independent risk factors of early ICH in ANPL were WBC≥30.00×109/L, Fibrinogen(FIB) < 2.92 g/L and PT≥12.91 s. A new early warning scoring system was established based on the weights of the above three factors. The area under ROC curve of the scoring system was 0.774 (95%CI: 0.688-0.859). The area under the ROC curve of the scoring system was 0.715 (95%CI: 0.559-0.872) confirmed by the validation group. Conclusion The new early warning scoring system could predict the occurrence of early ICH in ANPL and guide the medical staff to identify potential critical patients as early as possible.

Objective To explore the expression of OPA interacting protein 5 (OIP5) in pancreatic cancer and its effect on the proliferation of PANC-1 cells. Methods The expression of OIP5 in pancreatic cancer and adjacent tissues was evaluated by database; the expression of OIP5 mRNA and protein in human pancreatic cancer cell lines like MIAPaCa-2, PANC-1, KP-3 and BxPC-3 was detected by real-time quantitative PCR (RT-qPCR) and Western blot, respectively; the expression of OIP5 gene silencing plasmid (pGCSIL-shOIP5)and control plasmid(pGCSIL-shCtrl)were observed, respectively infected with PANC-1 cells, then divided into OIP5 gene silencing group and shctrl control group. 5 days later, RT-qPCR and Western blot were used to detect slow virus knockdown efficiency, and flow cytometry was used to detect cell apoptosis. MTT and cell count were carried out in OIP5 gene silencing group and shctrl control group for 5 consecutive days. OIP5 gene silencing group and shctrl control group were incubated for 10 days to form colonies, then Giemsa staining was used to count total number of sets. Results The expression of OIP5 mRNA in pancreatic cancer was significantly higher than that in normal pancreatic tissue(P＜0.05), and the overall survival rate in patients with high expression of OIP5 was significantly lower than that in patients with low expression of OIP5 (P＜ 0.05), and the disease-free survival rate was also significantly lower (P＜0.05); the expression of OIP5 was higher in MIAPaCa-2, PANC-1 and KP-3, but lower in BXPC-3 cell line; the results of MTT showed that OIP5 was silenced in the 4th day. The proliferation rate of PANC-1 cells was significantly decreased on the 4th and the 5th day (P＜0.01); the number of cell colonies (9 on average) after OIP5 silencing was significantly lower than that in shctrl control group (40 on average) (P＜0.01); the apoptosis rate of PANC-1 cells after OIP5 silencing was 8.3% and 4.5% higher than that of shctrl (P＜0.01). Conclusions OIP5 is highly expressed in pancreatic cancer cell lines. OIP5 gene can regulate the proliferation, apoptosis and clonal formation of PANC-1 cells, suggesting that OIP5 may play a role as a oncogene in the pathogenesis of pancreatic cancer, thus providing a potential biomarker for targeted treatment of pancreatic cancer.

Flood disasters are a prominent water safety problem for the major cities in China.Land use change has a great impact on the formation of flood disasters,and the comprehensive runoff coefficient is an important factor in response to the hydrological process of floods.Therefore,studying land use change and its impact on the comprehensive runoff coefficient is of great significance.With land use classification data from three phases of Landsat remote sensing images of Zhengzhou for 2000—2021,the spatio-temporal evolution characteristics of land use in Zhengzhou were analyzed,and the regional comprehensive runoff coefficient and the urban ground hardening rate were calculated.The following observations could be made from the results:① The land use in Zhengzhou underwent drastic changes during 2000—2021.Specifically,the area of construction land increased by 1 425.97 km2,while those of forest/grassland and cultivated land decreased by 777.25 km2 and 810.88 km2,respectively.② The percentage of the total area of land use conversion in Zhengzhou during 2000—2021 was 43.39%,and the conversion mainly took place among cultivated land,forest/grassland,and construction land.During the period of 2000—2014,the land use conversion was mainly from cultivated land and forest/grassland to construction land and from forest/grassland to cultivated land.During the period of 2014—2021,it was mainly from cultivated land to forest/grassland and construction land and from forest/grassland and construction land to cultivated land.③ During 2000—2021,the urban ground hardening rate of Zhengzhou increased from 12.32% to 31.14%,and its comprehensive runoff coefficient grew from 0.24 to 0.40.

This paper first analyzes the river system characteristics,hydrodynamic conditions,and status quo of water environment in the tidal river network area.On this basis,a preliminary connection scheme is then drawn up by the concept of connectivity in the graph theory based on “flow resistance” and the connectivity diagnosis and optimization method of river systems based on the “shortest path” idea.The scheme is further refined by a one-dimensional hydrodynamic mathematical water quality model.The results reveal that the scheme of minimum resistance connection by the graph theory is the optimal scheme of structural connectivity,and the problem of connection failure caused by the sluice control mode is solved after the scheme is refined by the mathematical model.This method can quickly diagnose the structural connectivity of river and lake systems,enrich the diagnostic means of river and lake connectivity,and provide a reference for the planning of river system connectivity in the tidal river network area of the Pearl River Delta.

Objective To investigate the problems existing in the work and study of refresher doctors in the Department of ultrasound in Peking Union Medical College Hospital(PUMCH) through questionnaire, in order to achieve precise management. Methods Refresher doctors in the department of ultrasound in PUMCH from April 2009 to September 2017, were asked to fill an electronic questionnaire on the WeChat platform. The questionnaire included gender, age, the professional title, the educational background, the grade of the hospital, the goal of the study, the satisfaction rate of teaching programs and job arrangement, the gains of the study and self-evaluation, etc. According to the educational background, professional title or grade of the hospital, they were divided into different groups. The differences of goals, satisfaction rate of teaching programs and job arrangement, main gains, number of articles and new technologies among different groups were analyzed. Results A total of 110 questionnaires were sent out, and 105 valid questionnaires were collected, and the effective rate was 95.5%. The need for management was significantly different, increasing in the order of the resident group, attending physician group and associate professor or professor group. Sixteen of the 17 refresher doctors (94.1%) who participated in the management of refresher doctors, believed that the experience of management was helpful. The number of articles was significantly different, increasing in the order of the resident group, attending physician group and associate professor or professor group. The satisfaction rate for teaching programs, job arrangement, the rate of publication of articles and development of new technologies were 87.6%, 54.3%, 22.9% and 45.7%, respectively. Conclusions The precise teaching programs make a high satisfaction, but the job arrangement, the training of new technologies and research capacity need to be further refined.

Early warning of rock collapse is one of the hot issues in the field of geotechnical engineering.The traditional monitoring and early warning methods of monitoring indicators are relatively uniform, with more attention being paid to the identification of accelerated damage precursors, which means that the early warning of collapse disasters has many inherent difficulties.In fact, rockblock collapse is caused by the dynamic failure of system instability, so it can be more effective to apply kinetic monitoring indicators to realize more scientific early warnings.In this paper, dynamic monitoring indexes were introduced to summarize the dynamic responses of rock and soil failure processes.A dynamic monitoring index based on natural vibration frequency can provide data for detecting damage in a dangerous rock mass.Based on the latest experimental research, it is concluded that the dynamic monitoring index can effectively reflect changes in physical and mechanical characteristics, and thus, can be used to dynamically and quantitatively analyze the damage and stability of a rock mass.A review of the literature on the current development of this field in China and abroad indicates that the early warning method of rock mass collapse disaster based on precursor failure identification in the detachment phase has better timeliness and will also to prove be more useful in future.Meanwhile, the development of an early warning index system of collapse is forecasted.An early monitoring and early warning index system based on dynamic, static, and environmental quantity indexes has greater potential for effective engineering monitoring and disaster warning.However, this new early warning method and its tripartite early warning indicator system offers a foundation for better responses to rock collapse in high-risk regions, and thus can improve the current passive prevention approach of rock-block monitoring and reduce the casualties and property losses that follow instantaneous rock collapse.This paper provides an effective reference for researchers studying early warning systems and the prevention of brittle damage disasters such as collapse.

Based on the 2018 statistical yearbook,this paper carries out the statistics and analysis on the agricultural non-point source pollution of the four major economic cities,namely Guangzhou,Dongguan,Shenzhen and Foshan in the Pearl River Delta by the inventory analysis method.The study found that:In 2018,the four cities in the Pearl River Delta produced 137 179.3 tons of COD,19 345.5 tons of TN,2 865.2 tons of TP,and 2 926.4 tons of NH+4-N from agricultural non-point source pollution,among which the COD is considered as the primary pollutant,mainly from livestock and poultry breeding,while TN,NH+4-N and TP mainly come from rural life and planting industry.In terms of regions,the pollutant emission intensity of Foshan is 427.42 kg/hm2,which is 1.5 times that of Guangzhou,ranking first among the four cities.The comprehensive water quality index caused by agricultural non-point source pollution in Guangzhou and Foshan is both greater than 4,so the two cities are considered as severely polluted areas,with heavy pressure to reduce agricultural non-point source pollution,while Dongguan and Shenzhen are lightly polluted areas.

This paper simulates the impact of the sewage outfall of the Macau Taipa Wastewater Treatment Plant on the water quality changes in the nearby Lingding Ocean by the hydrodynamic module (HD) and the transmission diffusion module (TR) of the MIKE21 model,provides the boundary conditions for the local two-dimensional tidal current model (built by MIKE21) through the one and two-dimensional integrated tidal current model of the Pearl River Estuary area,and analyzes the impact of pollutant diffusion under normal discharge and accident discharge in terms of the three evaluation factors,namely CODCr (chemical oxygen demand),SS (total suspended solids) and NH3-N (Ammonia-Nitrogen),under the “2005·6” flood combination and “2001·2” low water combination as the most unfavorable hydrological conditions.The results show that the water quality of main channel can meet the Class Ⅲ standard among the Sea Water Quality Standards (GB 3097—1997).With proper preventive measure,the out-of-limit water area under accidental discharge is less than 0.2 km2.This model has good adaptability to the simulation of the diffusion of pollutants into the coastal waters of Macau,so it can better simulate the impact of sewage discharge on the water quality of the sea under the action of ocean tides,and serve as a basis and research direction for the establishment of sewage outfall.

Large size and thick oxide transistors are usually used in the design of Low Dropout Linear Regulator(LDO) in order to increase the upper limited voltage of input supply voltage，but this will increase the area of the circuit. In order to solve this problem, this paper proposed a wide range voltage stabilizing circuit based on an improved Wilson current mirror structure, which provides power and bias for LDO. The simulation results show that the external supply voltage range from 3.5 V to 6 V can be converted to 1.8 V supply voltage, so that the LDO core circuit can still use 0.18 μm MOS transistors under the high input supply voltage, which can reduce the chip area. And it can bring convenience to the design of LDO analog module.

Prediction and prevention of rock burst in project is difficult because of its paroxysm and sudden destructiveness. Determining how to predict the time, place, and intensity of rock burst is one of the main engineering problems that must be solved via geotechnical engineering. Increasing number of experts from the field of underground mining and construction are applying new monitoring techniques and methods to study rock burst for its effective prediction. In the model experiment, the entire process of structuretype rock burst was remotely monitored via the laser Doppler vibrometer. Based on the dynamic theory and energy conservation law; the natural vibration frequency was used to analyze the elastic coefficient of the shear plane. The experimental results show that the incompatible weakness of structural plane is a necessary condition for the occurrence of rock burst, and the spatiotemporal difference of the structural plane strength is the main factor that determines the immediate or the time-delayed rock burst. Slow weakening of the structure causes time-delayed rock burst, whereas rapid weakening causes immediate rock burst. During the whole process of rock burst, the weakening rate of rock mass structure is determined using the natural vibration frequency, and the dissipated energy of the structure occupies merely 0.06% of the rock elastic energy. Thus, most of the elastic energy is released in the form of kinetic energy, and the rock is ejected with high velocity. Furthermore, the incompatible weakening characteristics of rock burst structural planes can be analyzed using the analysis of the frequency decline rate. Therefore, the new monitoring index of dynamic characteristics such as natural vibration frequency improves the understanding of evolution characteristics of rock burst and plays a significant role in the early warning of rock burst in underground engineering.

A magnetic resonance imaging receiver design based on NI PXIe-7966R is proposed, with which the magnetic resonance signals are sampled directly and down-converted digitally, the raw data are uploaded and the magnetic resonance image are restored. The system-level digital signal processing (DSP) development tools offered by NI LabVIEW field programmable gate array (FPGA) was used for FPGA function modeling, simulation and automatic code generation of hardware description language (HDL). It was very flexible during the digital down conversion (DDC) designing. The sampling rate of this module was 50 Mbps, and the receiver bandwidth could be varied between 100 Hz and 1 MHz. The experimental results showed that the receiver design is a high performance magnetic resonance receiver solution.

Objective To explore the value of dynamic susceptibility contrast-enhanced perfusion-weighted imaging (DSC-PWI) in superficial temporal artery-middle cerebral artery (STA-MCA) bypass and to provide radiological evidence for hemodynamic changes in STA-MCA bypass in the treatment of severe internal carotid artery (ICA) and MCA stenosis and/or occlusion. Methods A total of 76 cases (65 males and 11 females with average age of 55) who underwent STA-MCA bypass from January 2011 to February 2016 were included. Routine MRI and DSC-PWI were performed within one month before operation and within one week after operation. Hemodynamic changes [relative cerebral blood flow (rCBF), relative cerebral blood volume (rCBV), relative mean transit time (rMTT) and relative time to peak (rTTP)] of MCA blood supplying area at basal ganglia section (proximal end) and centrum semiovale section (distal end) were compared before and after operation. Results Compared with before operation, rCBF was significantly increased after operation at ipsilateral basal ganglia section (proximal end, P = 0.000) and centrum semiovale section (distal end, P = 0.001). rCBV at basal ganglia section was significantly increased after operation (P = 0.021), while rCBV at centrum semiovale section had no significant difference compared with before operation (P = 0.844). rMTT (P = 0.000, 0.000) and rTTP (P = 0.000, 0.000) at ipsilateral basal ganglia section and centrum semiovale section were significantly reduced after operation. Conclusions STA-MCA bypass can improve cerebral blood perfusion of MCA blood supplying area. DSC-PWI could assess the hemodynamics of ischemic area, so it is the optimal noninvasive technology to evaluate the curative effect of bypass and observe cerebral hemodynamic changes dynamically. DOI: 10.3969/j.issn.1672-6731.2017.06.010