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Coal mining engineering involves complex stress structure time effect issues, which are closely related to the occurrence and prevention of rock burst disasters. Therefore, this study conducts experimental research on the stress structure time effect of impact coal. Coal rock specimens were obtained from three coal mines in Shaanxi, Gansu, and Inner Mongolia. The stress-time effect of loading rate was studied through coal uniaxial compression static-dynamic load and creep tests. The stress-time effect under the condition of coal in situ release was investigated using a long-term segmented test method. Water immersion tests on coal and structural time-effect studies on coal-rock combinations were conducted. The experimental results indicate that there is a positive correlation between the uniaxial compressive strength of coal and the loading rate, and a negative correlation with the duration of in-situ relief and immersion time. The combined mode of coal-rock structure time effect significantly affects its energy and strength properties, while impact coal exhibits both stress and structural time effects. According to the experimental results, a plastic limit structure is proposed to explain the irreversible deformation of coal-rock mass under stress. Furthermore, by constructing a time-dependent model for plastic strain in coal under impact conditions and comparing the numerical approximations of non-elastic strain and irreversible strain, the plastic limit strain characteristics of shock-induced coal were verified.

Collaborative encirclement of multiple unmanned ground vehicles (UGVs) is a focal challenge in the realm of multiagent collaborative tasks, representing a fundamental issue in complex undertakings such as multiagent collaborative search and interception. Although optimization algorithms have yielded rich research outcomes in collaborative encirclement, challenges persist, including poor real-time computational efficiency and weak robustness. Reinforcement learning theory holds considerable promise for addressing multiagent sequential decision problems. This paper delves into the study of the collaborative encirclement of multiple UGVs based on deep reinforcement learning theory, focusing on the following key aspects: establishing a kinematic model for UGVs to describe the collaborative encirclement task, detailing the collaborative encirclement process, developing strategies for target UGV escape, and addressing challenges arising from the increasing number of UGVs, which results in a complex environment and issues such as algorithmic instability, dimension explosion, and poor convergence. This paper introduces a collaborative encirclement algorithm based on the soft actor–critic (SAC) framework. To address issues related to poor collaboration and weak generalization among multiple UGVs, long short-term memory is incorporated into the network structure, serving as a memory function for UGVs. This tactic aids in capturing and using information from historical observation sequences, effectively processing time–series data, making more accurate decisions, promoting mutual collaboration among UGVs, and enhancing system stability. To tackle the issue of increased state space dimensions and low training efficiency during collaborative encirclement, an attention mechanism is introduced to calculate and select attention weights in the state space, focusing attention on key states relevant to the task. This strategy helps constrain state space dimensions, ensuring network stability, achieving stable and efficient collaboration among multiple UGVs, and improving algorithm training efficiency. To address the problem of sparse rewards in collaborative encirclement tasks, a mixed reward function is proposed that divides the reward function into individual and collaborative rewards. Individual rewards guide UGVs toward the target, incentivizing their motion behavior, whereas collaborative rewards motivate a group of UGVs to collectively accomplish the encirclement task. This approach further guides UGVs to obtain more frequent reward signals, ultimately enhancing the algorithm convergence speed. Simulation and experimental results demonstrate that the proposed method achieves faster convergence than SAC, with a 15.1% reduction in encirclement time and a 7.6% improvement in success rate. Finally, the improved algorithm developed in this paper is deployed on a UGV platform, and real-world experiments in typical encirclement scenarios validate its feasibility and effectiveness in embedded systems.

In order to study the pattern of quality changes in selenium-rich rice during storage, selenium-rich rice and non-selenium-rich rice produced in Enshi and Jingzhou of Hubei province were subjected to accelerated aging for 180 days under high temperature storage conditions (35 ℃, and 50% relative humidity) in an artificial climate incubator. The storage characteristics, gelatinization characteristics and edible quality were measured and analyzed every 30 days. The results showed that with increasing storage time, the trends of changes in all tested indicators were consistent between selenium-rich rice and non-selenium-rich rice, but the degree of change was different. On day 180, the germination rate of non-selenium-rich rice was 69.7% and 65.7% for the cultivars Ezhong 6 and Daojingliangyou, the content of fatty acids increased by 40.43% and 59.74% compared with those on day 0, and α-amylase activity was 0.26 and 0.22 U/g, respectively. For these two cultivars, the germination rate of selenium-rich rice was 66.7% and 64.0%, and the content of fatty acids increased by 53.99% and 78.47% compared with those on day 0, and α-amylase activity was 0.24 and 0.19 U/g, respectively. Compared with the control group, selenium-rich rice had lower germination rate, lower α-amylase activity and higher fatty acid value, indicating no obvious advantages in storage quality. On day 180, the content of malondialdehyde (MDA) was 0.36 and 0.28 μmol/g in ordinary Ezhong 6 and Daojingliangyou rice, the content of free phenols was 341.78 and 371.59 μg/g, and free sulfhydryl group content was 0.67 and 0.64 μmol/g, respectively; for selenium-enriched Ezhong 6 and Daojingliangyou rice, MDA content was 0.31 and 0.24 μmol/g, free phenol content was 368.33 and 399.22 μg/g, and free sulfhydryl group content was 0.89 and 0.74 μmol/g, respectively. Compared with the control group, selenium-rich rice had lower MDA content, and higher contents of free phenols and free sulfhydryl groups, indicating better antioxidant capacity during storage. In terms of gelatinization characteristics, texture characteristics and edible quality, compared with the control group, selenium-rich rice had higher peak viscosity, lower gelatinization temperature, lower hardness, higher viscosity, higher elasticity and higher taste score during the same storage period. In conclusion, selenium-rich rice had better antioxidant capacity and higher taste score during storage at 35 ℃, but did not show anti-aging advantages.

The 1∶500000 seismotectonic map of the Ordos active block and boundary zone is a special achievement of the national key research and development project “Research on dynamic model and strong earthquake risk of Ordos active block boundary zone” . Taking the Ordos active block and boundary zone as the mapping scope, this map refers to the compilation standards and database standards of seismotectonic map in the seismic industry, and carries out high-resolution image interpretation on the basis of systematically collecting and collating geographic information, geology, active tectonics, earthquake, geophysics and other data. It absorbs the latest research results of the project and builds the basic database required for mapping. Through data vectorization, stratigraphic boundary modification, fault modification, map modification, the 1∶500000 seismotectonic map of the Ordos active block and boundary zone was compiled. This map reflects the boundary zone of Ordos active blocks such as Yinchuan Basin Helan Mountains, arc structure bundle, Weihe Basin, Shanxi graben system, Hetao Basin and the seismic structure of adjacent blocks, the geometric and kinematic images of active tectonics in the Ordos block and boundary zone were improved.

To determine the impact of high-temperature-induced thermal damage on the acoustic emission characteristics and fracture mechanism of granite during various stress stages, uniaxial compression tests and real-time acoustic emission monitoring of thermally damaged granite at 25, 200, 400, and 600 ℃ were performed. The peak frequencies of thermally damaged granites, the distribution characteristics of RA-AF (AE rise time/AE amplitude-AE average frequency) data, and the distribution patterns of energy concentration \begin{document}$\rho $\end{document} at various loading stages were investigated. The results show that the stress stages of granite under uniaxial compression conditions after thermal damage at each temperature can be divided into the following stages: Stage Ⅰ corresponds to the crack compaction stage; Stage Ⅱ corresponds to the crack emergence and stable development stage; Stage Ⅲ corresponds to the crack unstable development stage; and Stage Ⅳ corresponds to the post-peak damage stage based on the acoustic emission development characteristics. Further, the more severe the thermal damage to the granite, the earlier the granite enters Stage II and the longer the duration of this stage. The acoustic emission peak frequency of thermally damaged granite at different temperatures exhibits a band distribution across four principal frequency regions. With increasing severity of thermal damage, the generation of medium- and high-frequency fracture signals occurs earlier, resulting in a wider distribution range of the primary frequency bands. In addition, there is a decrease in the occurrence of ultrahigh frequency signals during the failure stage. The distribution characteristics of the acoustic emission RA-AF data of the thermally damaged granite at different temperatures can provide insights into the cracking mechanism observed during different stress stages. Subsequently, Stage I generates a small amount of tensile and tension–shear cracks; Stage II generates mixed tension–shear cracks; Stage III generates tensile and mixed tension–shear cracks while shear cracks continue to develop and enlarge; and Stage IV generates numerous shear cracks. The thermally damaged granite is more likely to produce shear cracks under pressure. The higher the temperature of thermal damage, the more shear cracks develop. The curve of energy concentration based on acoustic emission data during uniaxial compression of granite contains three major stages: the initial irregular fluctuation, stable, and abrupt drop stages, which have obvious correspondence to stages I, II, and III, respectively. The abrupt change point between the stable and abrupt drop stages of the energy concentration curve can be used as a failure precursor for granite samples under uniaxial compression.

Due to the advantages of long service life, compact structure, strong environmental adaptability and high inherent safety, the heat pipe reactor power supply system is worth studying. The NUSTER2.0 dual-mode heat pipe reactor non-nuclear prototype built by Xi’an Jiaotong University adopts the integrated design of “simulated reactor core-high temperature heat pipe-Stirling generator-thermoelectric power generation”. The combination of the dynamic module coupled with Stirling and the static module coupled with thermoelectric power generation device can meet the diversified demands of energy. In this paper, the steady-state experiment of NUSTER2.0 was carried out to verify the design, and the system coupling simulation of the prototype was carried out by COMSOL multiphysics to analyze its operation and mechanical characteristics. In the 15 kW thermal power steady-state experiment, the generating power of the dynamic module is 2 019 W, and the static module is 493.2 W. The overall thermoelectric conversion efficiency is 16.7%, which verifies the engineering feasibility of the design. The system simulation model is coupled with the thermal resistance network model of high temperature heat pipe, the equivalent thermal conductivity model of thermoelectric power generation device and the Stirling adiabatic analysis program. The heat source of fuel rod and the heat sink of cooling water were simulated by heat flux boundary and convective boundary respectively. Under 15 kW thermal power, the steady-state simulation results are in good agreement with the experimental results on both the heat pipe temperature distribution and the main operating parameters of the dynamic and static modules, while the maximum relative error is 6.73%, which verifies that the coupled model is reliable. The variable thermal power steady-state simulation determines that the limit due to Stirling is 16.5 kW, and predicts that the static module will reach the peak efficiency near 25 kW. The system start-up transient simulation obtains the start-up characteristics under the 3.5-10.15 kW stepped power platform. The prototype start-up strategy based on the combination of power platform cold start and thermal insulation restart was also proposed. The thermal-mechanical coupling simulation indicates that the stress danger zone of the system is the coupling between the heat pipe and assembly matrix. Under 15 kW thermal power, the maximum stress at the coupling of heat pipe-core matrix and heat pipe-collector matrix are 160 MPa and 97 MPa, respectively. In the experiment, the self-adjusting function of the Stirling insulation ring can significantly relieve the 366 MPa stress between it and the Stirling matrix. The thermal expansion rate of the reactor core is 1.21%, which will cause negative feedback on the reactivity. The simulation results provide the numerical basis for the operation safety analysis and further experimental design of the NUSTER2.0 prototype.

To further meet the requirements for using pipeline steel in extreme environments and to improve its safety in service, the inclusion control level in pipeline steel urgently needs improvement. In this paper, the variation laws of inclusion type, size, and composition in the refining process of X80 pipeline steel were studied through industrial trial sampling, and the evolution mechanism of inclusions during calcium treatment and steel cooling and solidification was analyzed using thermodynamic calculations with FactSage 8.1 software. The trial results showed mainly MgO–Al2O3 and MgO–Al2O3–CaO inclusions after LF refining in proportions of 25% and 75%, respectively, with sizes mainly distributed between 1–5 μm, and the proportion of inclusions of 1–2 μm and 2–5 μm were 56.0% and 37.3%, respectively. The contents of T[O] and [N] were reduced from 0.0022% and 0.0059% after LF refining to 0.0010% and 0.0035% after RH refining, respectively, and the number density of inclusions was reduced from approximately 23.07 mm−2 after LF to 7.44 mm−2, with an inclusions removal rate of approximately 67.8%. The inclusions were mainly MgO−Al2O3–CaO and CaS–Al2O3–CaO systems during calcium treatment, the average CaS content in the inclusions increased from 8% after RH refining to 36%, and the average CaO content decreased from 24% to 12%. After soft blowing, the SiO2 content ranged from 0 to 2.5% in the inclusions smaller than 40 μm and from 6.0% to 8.0% in the inclusions larger than 40 μm, and the inclusions larger than 40 μm were mainly CaO–Al2O3–MgO–SiO2, whose chemical composition is essentially identical to that of the refining slag, whose source is the refining slag involved; thermodynamic calculations show that when the [Ca] content is between 10.5×10–6–15.8×10–6, all spinel inclusions are modified, and all the inclusions are liquid calcium aluminates; when the steel is at casting temperature, the inclusions are mainly liquid calcium aluminates, and when the temperature is lowered to 1428 ℃, the liquid inclusions completely transform into solid. As the temperature drops below 1309 ℃, the type of inclusions essentially remains constant. During the entire temperature drop, the CaO content in the inclusions decreased, and the CaS content increased.

To explore the protective effect and possible mechanism of probiotics combined with resveratrol on chronic alcoholic liver injury, C57BL/6J mice were used to construct chronic alcoholic liver injury model. Mice were randomly divided into the control group (Con group), themodel group (Mod group), three intervention groups of probiotics combined with resveratrol (Res) (Lactobacillus paracasei J5+Res (J5+Res), Lactobacillus casei YRL577+Res (YRL577+Res), Bifidobacterium animalis F1-7+Res (F1-7+Res)) groups, and the positive drug tiopronin group (LP group). After the experiment, the liver lipid content, alcohol metabolism enzyme activities, oxidative stress level and other indexes of mice were investigated. In order to further explore the mechanism of the combined action, the mRNA expressions of oxidative stress related genes CYP2E1, nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in liver were analyzed. The results showed that compared with Mod group, probiotics combined with resveratrol could significantly reduce the contents of triglyceride, total cholesterol, serum aspartate aminotransferase and alanine aminotransferase activites in liver of mice (P

Objective To explore the teaching effect of mind mapping to implement the concept of “ student-centered learning (SCL)”. Methods One hundred and eighteen undergraduates of four-year program in Nursing School, Peking Union Medical College enrolled in 2019 were selected as objects. Before the learning of the human parasitology, the students were investigated to find current situation of “students' autonomous learning”;Then they were guided to make up a mind map of what they need to learn in the course of human parasitology and the effect of mind mapping was evaluated at the end of the course. Results This method guided students to make up a mind map and so effectively stimulated their enthusiasm of active learning. This method significantly strengthened students' self-confidence,supported their deep understanding of knowledge and build their capacity of logic attitude of learning. This method may contribute to encourage and orient students' autonomous learning. Conclusions The application of mind mapping is an effective and feasible method to practice education concept of “student-centered learning” concept.

On June 9，2020，an earthquake measuring ML3.4 occurred in Shapotou District，Zhongwei City，Ningxia. The earthquake occurred in the meizoseismal area of the 1709 M7½ earthquake of South Zhongwei，and its epicenter is located in an area where there were relatively few weak earthquakes in the past. In this paper，based on the waveform records of the Ningxia regional seismic network，the focal mechanism solution and focal centroid depth of the Zhongwei ML3.4 earthquake on June 9，2020 are inversed using the gCAP method. The focal mechanism solution is also calculated by the Hash method，and the central focal mechanism of these two methods is obtained. The result shows that the focal mechanism solution of gCAP method is strike 255°，dip 79°，rake −20° for nodal plane I，and strike 348°，dip 70°，rake −160° for nodal plane II，and the centroid depth is 12 km，and that the focal mechanism solution of Hash method is strike 344°，dip 89°，rake 176° for nodal plane I，and strike 74°，dip 86°，rake 1° for nodal plane II. The central focal mechanism solution of the two methods is strike 255°，dip 87°，rake −11° for nodal plane I，and strike 346°，dip 80°，rake −176° for nodal plane II，and the principal stress axis is mainly in NE direction. The minimum 3-D rotation angle between the gCAP method result and the central focal mechanism is relative small，which is 12.09°. Combing the past geologic structure data，we deduces that the main dislocation of Zhongwei ML3.4 earthquake on June 9，2020 is the left-lateral slip，and that the fault is more likely to belong to the nodal plane in NEE direction.

China has maintained the world’s highest zinc production for many years, which has generated a tremendous amount of zinc slag, and 60% of which has not been effectively treated. Most of this slag is zinc leaching residue produced by the hydrometallurgical processing of zinc. The accumulation and storage of zinc leaching residue requires large tracts of land and harmful elements like arsenic and cadmium in the residue contaminate the surrounding soil and groundwater. From another perspective, zinc leaching residue represents a solid waste resource with a very high comprehensive utilization value. For example, many valuable metals are present in zinc leaching residue, including zinc, lead, and silver, which have high recovery values. In addition, zinc leaching residue can be fully utilized to produce cement, glass, ceramics, and a range of chemical materials. The comprehensive recovery and total material utilization of zinc leaching residue would help to significantly reduce the burden of its storage. This paper summarized research progress on the recovery of valuable metals from and the total material utilization of zinc leaching residue. Two main methods were used to recover valuable metals from this residue: pyrometallurgical and hydrometallurgical processes. Based on a detailed comparative analysis of the advantages, disadvantages, and feasibility of various typical recovery processes, this paper proposed a combined method of bioleaching and chloride leaching for the efficient extraction of zinc, lead, and silver from zinc leaching residue. This combined method has good applicability to different types of zinc leaching residue and good prospects for industrial application. In addition, this paper introduced the progress achieved in the total material utilization of zinc leaching residue and the future development prospects for utilization technologies. The total material utilization of zinc leach residue should be developed to product high-performance, sophisticated, environment-friendly and energy-efficient materials. Greater economic benefit can be gained while realizing clean production in the zinc industry.

Objective To investigate the epidemiological and forensic characteristics of multiple organ dysfunction syndrome （MODS） after severe trauma and explore the reference indexes for determining traumatic MODS. Methods In terms of the number of organs or systems involved in MODS, the number of failures of each organ or system, the first failing organ and the survival time after organ failure, 72 cases of MODS death caused by traffic accidents were retrospectively analyzed. The cases were divided into two groups according to the mean injury severity score （ISS）. The t test was used to analyze the differences in the number of organs or systems involved in MODS in the two groups. Chi-square test was used to analyze the differences in the types of first failing organs and the differences between the two groups in the number of cases of organ or system failure involved in MODS. Wilcoxon signed-rank test was used to analyze the differences between the two groups in survival time of MODS after trauma. Kaplan-Meier survival curve was drawn and Log-Rank test was performed. Results The number of MODS involved organs or systems after trauma in ISS≤35 group was 3-5, and 2-4 in the ISS>35 group （P35 group （P35 group was relatively low and the decline was steep （P35 can be used as reliable reference indexes for evaluation of the causal relationship among trauma, MODS and death.

In recent years,structural magnetic resonance imaging (sMRI) and functional magnetic resonance imaging (fMRI) are widely used in depression research.From the perspectives of morphology,structural network and functional network,the brain abnormalities of depression were explored to understand the pathogenesis,and to assist doctors in clinical diagnosis,treatment and prognosis.A large number of researches have found that the hippocampus and amygdala of depression showed different degrees of atrophy,and the connection strength of brain network and graph theory attributes showed significant abnormal.Moreover,the abnormal brain areas were related to emotional regulation,attention and cognitive control,and the degree of abnormalities were highly correlated with the severity of depression.The research actuality of depression from different perspectives was reviewed,and some suggestions for future research were put forward.

Objective To investigate the contamination situation of Salmonella at different times, slaughtering and processing sites in a broiler slaughter factory to acquire the key contamination point. Methods Chicken anal swabs, carcasses and broiler samples in different slaughtering stages were timely collected in a broiler slaughterhouse in Shaanxi Province from November 2016 to November 2017, Salmonella concentration was quantitatively detected by most probable number (MPN) method, Salmonella isolate recovered from positive samples were identified by polymerase chain reaction (PCR) combined with serum agglutination techniques. Results Among the 284 samples, 67 (23.6%) were positive to Salmonella, the average MPN value was 0.051 6 MPN/g. During sampling period, samples in July was the most frequently contaminated with the positive rate of 37.8% (14/37) and average MPN value of 0.064 7 MPN/g. the lowest Salmonella contamination rate was detected in November 2016 (13.9%, 5/36) with average MPN value of 0.043 6 MPN/g. Among different processing stages, the highest positive rate was detected after scalding and fading (43.3%, 26/60), the average MPN value of which was 0.060 5 MPN/g. The positive rate of chicken breast before freezing was the lowest (18.3%, 11/60), and the average MPN value was 0.036 8 MPN/g, which was slightly higher than that of the whole chicken carcass/chicken breast collected from distribution and storage processes (0.035 8 MPN/g). Conclusion The result showed detection rate and MPN values of Salmonella positive samples in broiler slaughtering process had a strong seasonality, detection of Salmonella in different slaughtering stages indicated that vertical and cross-contamination might happen during the whole process. It was necessary to strengthen the regulation of broilers processing as well as the critical control points.

In the 5G era,growth of network traffic is driven by the development of emerging services,especially the burst of east-west traffic.The network evolved from a multi-layered planar architecture to a three-dimensional architecture,thereby promoting the development and application of all-optical switching technology.The development and technology evolutions of optical switching architecture were introduced,the key enabling technologies and applications of all-optical switching equipment were described,and the future trends of all-optical switching technology were discussed.

Objective To explore the clinicopathological features of adult medulloblastoma with myogenic differentiation and to discuss clinicopathological differentiations from relevant tumors, so as to improve the ability of diagnosing and differentiating this kind of tumor. Methods The clinical manifestations, imaging, pathological features and immunohistochemical features of one case of adult medulloblastoma with myogenic differentiation were analyzed, and related literatures were reviewed. Results A 32-year-old female patient presented with repeated distortion of mouth and facial numbness for over 6 years. T1WI showed a mixed-signal lesion in the cerebellar vermis and dorsal part of brainstem, and protruded toward the fourth ventricle. Enhanced T1WI showed a round strengthened nodule in the lesion. During operation, it was seen that the tumor arised in cerebellar vermis, projected into the fourth ventricle and invaded brainstem. On microscopy examination, it was found that oval nuclei tumor cells were distributed in sheet or scattered patterns, and neuroblastic rosettes were observed. Abundant and eosinophilic cytoplasm, eccentrically placed and atypical nuclei containing hyperchromatic chromatin or prominent nucleoli in the tumor could be displayed. Mitoses were frequently seen. The tumor also presented with fresh and old hemorrhage in some place. Immunohistochemical staining showed that tumor cells were diffusely positive for integrase interactor 1 (INI1), synaptophysin (Syn), chromogranin A (CgA), human internexin neuronal intermediate filament protein α (INα), neurofilament protein (NF), Nestin (Nes), β-catenin and P53, and partly positive for desmin (Des), neuronal nuclei (NeuN) and S-100 protein (S-100), but negative for glial fibrillary acidic protein (GFAP), oligodendrocyte transcription factor-2 (Olig-2), CD99, pan cytokeratin (PCK), epithelial membrane antigen (EMA), MyoD1, myogenin, muscle-specific actin (MSA) and smooth muscle actin (SMA). Ki-67 labeling index was about 10% . Pathological diagnosis was medulloblastoma with myogenic differentiation (WHO Ⅳ). The patient was not given further treatment including chemotherapy or radiotherapy after surgery. Nine-month follow-up showed no tumor recurrence. Conclusions Medulloblastoma is a malignant, invasive embryonal tumor commonly occuring in the cerebellum of children. Medulloblastoma with myogenic differentiation occurs very rarely in adult, which is characterized by containing primitive neuroectodermal and rhabdomyoblastic elements. The diagnosis should be differentiated from central nervous system primitive neuroectodermal tumor (PNET), atypical teratoid/rhabdoid tumor (AT/RT) and rhabdomyosarcoma. DOI: 10.3969/j.issn.1672-6731.2015.09.009

Background Pilocytic astrocytoma (PA) is a low⁃grade glioma that occurs mainly in the cerebellum of children and young adults. This article is to report a rare case of PA with angiocentric arrangement in the supratentorial region of a 28-year-old male. The pathomorphism of this tumor is different from that of typical PA, since most tumor cells grow in single layer around the hyalinized degenerative vessels, that is to say, angiocentric pattern. This paper aims to discuss the clinical, imaging and pathological features of PA with angiocentric arrangement and clinicopathological differentiations from relevant tumors, so as to improve the ability of diagnosing and differentiating this kind of tumor. Methods and Results A 28-year-old male with no significant past history presented with repeated grand mal seizures and did not recover in the treatment with antiepileptic drugs. Physical and neurological examinations were normal. Electroencephalography (EEG) found no typical epileptic wave or focal δ wave. CT and MRI showed a superficial cystic mass with a mural nodule and clear boundary in the left frontal cortex. During the resection of the tumor, the lesion was identified as cystic structure on the surface and solid structure within the cyst wall. Optical microscopy findings revealed that tumour cells with round or oval nuclei and cytoplasm showing slender hair-like protuberance of both ends were arranged in single layer around hyalinized blood vessels. Some tumor cells with fusiform nuclei showed compact fascicles or loose stellate reticulum. Rosenthal fibers and eosinophilic granular bodies were occasionally seen. According to immunohistochemical staining, the tumor cells were diffusely positive for glial fibrillary acidic protein (GFAP), Vimentin (Vim), S-100 protein (S-100), Nestin, CD56, and focally positive for Olig2, while the tumor cells were negative for epithelial membrane antigen (EMA), isocitrate dehydrogenase 1 (IDH1), P53, neuronal nuclei antigen (NeuN), neurofilament protein (NFP), synaptophysin (Syn) and CD34. The overall MIB-1 labeling index was 1%. According to these findings, the tumor was diagnosed as PA with angiocentric arrangement in the left frontal lobe (WHO Grade Ⅰ). The patient was not given further treatment including radiotherapy or chemotherapy after surgery. One year follow-up showed no onset of seizures or tumor recurrence. Conclusion This is the first case report of a cerebrellum PA with extensive angiocentric arrangement in an adult. According to the clinical and histomorphological (including the angiocentric arrangement) features, the differential diagnosis should include pilomyxoid astrocytoma, astroblastoma, angiocentric glioma, cortical ependymoma and papillary glioneuronal tumor.

研究是重要的知識探索過程，採用嚴謹的研究方法與適當的統計分析技術，清楚且有系統的呈現研究發現，能促進學域知識的發展。高品質的學術論文，是學域專業彰顯最重要的支撐。因此為瞭解圖書資訊學研究的發展趨勢，其研究方法與統計分析技術的應用，是相當值得探討的議題。鑑此，本研究針對近四十年來刊登在《教育資料與圖書館學》期刊之1,540篇研究論文，進行書目計量與內容分析，並依其刊物沿革、宗旨及演進過程，將研究期間區隔為四期，探析其自1970年創刊迄2010年所刊載的論文特徵，包括文章類型、論文語文、主題類別、論文結構、研究方法及統計分析技術等面向。研究結果發現，在文章類型上，第一期的文章類型共11種類型最多；在語文類別上，以中文論文刊載為主；在主題類別上，所刊載之論文以「圖書資訊學」（66%）所占比例最高，其次是「教育」（15%）；另在論文結構部分，有42篇（2.73%）的論文採用ILMRAD結構撰寫論文，另有8篇採用IMRAD結構，且多集中於第四期。至於最常採用的研究方法為調查法，其中主題類別為「圖書資訊學」的論文採調查法（46.63%）最多；次為「教育」類論文，約12%採用調查法；而最常採用的統計分析技術是量化敘述統計（60.11％），次為T檢定（9.27％）。Research is the important process of knowledge exploration. Domain knowledge development can be improved by using research design and proper statistical methods meticulously as well as clearly and systematically displaying research results. In order to find out the evolving trend of Library and Information Science, its research design and statistical method is a topic worth exploring. By applying bibliometric and content analysis, this study investigates the 1,540 research papers published in the Journal of Educational Media & Library Sciences (JoEMLS) in the last 40 years. According to its history and mission statement, the researchers separate time span from 1970 to 2010 into four period, exploring the features of those published papers, including the type of articles, article languages, topics, structures, research designs and statistical methods. The results show as follow. During period 1, the type of articles are diversities. In addition , Chinese papers are dominate. Moreover, the top 3 categories of research papers are the study of “Library and Information Science”(66%), follows by the “Education”(15%). As for the paper structure, there are 2.73% papers applying ILMRAD and only 8 papers of them applying IMRAD. The most commonly adopted research design is Survey Method, among them, the study of “Library and Information Science” used more often (46.63%). As to the most commonly used statistical method is Descriptive Statistics (60.11%), secondly the T-Test(9.27％).

本研究旨在探討美國公共圖書館生涯資訊服務之內涵，以及施行生涯資訊服務之館員對此項服務之功能、困難及挑戰、館員扮演之角色與應具備之條件、及未來發展方向等層面之看法。本研究以美國公共圖書館負責生涯資訊服務之124 位館員或主管為研究對象，採用網路問卷調查法，並輔以電子郵件訪談，藉以深入了解服務之具體內容與受訪者內心的想法。研究結果顯示美國公共圖書館生涯資訊服務內涵方面，主要包括提供豐富的生涯館藏與製作相關資料、成立生涯資訊中心、提供資訊轉介服務、舉辦專題講座、及行銷生涯資訊服務等。本研究亦綜合研究結果，就圖書館規劃之服務內容、館員的在職訓練、及館員宜具備之人格特質與專業知能等面向，提出數項建議藉以供國內未來規劃施行生涯資訊服務之公共圖書館參考。 Employing an on-line questionnaire and email interview, this study investigated the content of career information services of American public libraries. 124 librarians or managers responsible for the services were surveyed about their opinion on the functions, difficulties and challenges of the services, and the librarians’ role and qualifications and how they perceive the services in the future. The results indicate that American public libraries participating in this study offer a wide variety of career collections, found career information centers, provide referral services, give workshops, and market the services. 頁次：66-87

Background: Aging and age-related health problems are major issues of concern for community health services. Yoga is an exercise with both physiological and psychological effects on aging. Although many studies have assessed the effectiveness of yoga in the elderly, little information is available in the literature to support empirical conclusions. Purpose: This review synthesizes and characterizes findings related to the effects of yoga on depression and quality of sleep in the elderly. Method: Researchers used keywords including yoga, elderly, aged / older adult, depression, sleep, and quality to search 6 electronic databases for relevant studies published prior to March 2013. Inclusion and exclusion criteria were used to screen identified study abstracts. The Jadad scale appraised the quality of identified studies. Results: Seven studies met the inclusion criteria. Five studies found significant changes in participant depression symptoms after doing yoga. Three studies found significant effects on the quality of sleep of participants after 6 months of doing yoga. Conclusion: Yoga significantly reduced the depressive symptoms of elderly participants and improved their quality of sleep after 6 months. Findings were similar for elderly living in institutions and in the community. However, the majority of participants in the assessed studies were women characterized by a high level of social participation and proactive participation in health promotion activities. Future studies should broaden the scope of research to address different aging populations and use long-term cohort observations in order to better elicit the effectiveness of yoga and to develop strategies to introduce yoga into daily activities. [ABSTRACT FROM AUTHOR]

The negative effects of smoking during pregnancy are well documented. Health care providers typically advise pregnant women who smoke usually to quit for their health as well as for the health of their fetus. Most women are familiar with the need to stop smoking while pregnant. Hospitals offer various smoking cessation services. However, the literatures reveals a low uptake of smoking cessation services among pregnant women. The purpose of this paper is to explore the smoking cessation experience and feelings amongst women during pregnancy and assess smoking cessation intervention in antenatal care. Findings may provide health care providers a better understanding of this issue and help women overcome related challenges. [ABSTRACT FROM AUTHOR]

Taking the benchmarks of industry market size, industry association, dynamic comparative cost, bottleneck effect, and comparative advantage and the Shinohava benchmark as the standards to frame index system, an evaluation index system composed of five levels and eight indices is built for the choice of pillar industries. The system takes full account of the economic and cultural factors and introduces the factor analysis in the decision made to pick out the pillar industries in Liaoning province, with relevant data collected and a qualitative analysis made for the pillar industries thus picked out. Combining quantitative analysis with qualitative analysis, the machine-building, electric power supply, real estate and building industries are picked out as the four pillar industries in Liaoning province. Among them the machine-building industry is regarded as the No. 1, and its developmental strategy is discussed. [ABSTRACT FROM AUTHOR]

In engineering construction, cement quality directly affects the safety of construction projects. So it is necessary that we use qualified cement in the engineering structure. It is of great signification that a method detects cement raw material rapidly to adjust the mixture ratio of raw ores to ensure the cement quality. Traditional detection method needs sampling, sample preparation and test, etc. With many procedures, the test results are seriously lagged behind the production process. This paper introduces a set of online analysis equipment to determinate elemental composition of cement powder timely based on laser induced breakdown spectroscopy. This equipment is composed of a LIBS detection system and a pneumatic system. The equipment can achieve the real-time measurement for it needn’t sample preparation. Thus, it can guide cement raw material proportioning in time. In this paper, we have quantitatively analyzed the main components of Al2O3, CaO, Fe2O3, MgO and SiO2 in the cement raw materials using the full spectrum normalization method as well as the support vector machine. The corresponding maximum absolute errors were 0.34%, 0.35%, 0.07%, 0.14%, and 0.55%, respectively. Results showed that the measurement results of the newly developed LIBS equipment are in accord with those of the conventional chemical method. Furthermore, the measurement precision is in line with X-Ray fluorescence spectrometry. It is confirmed that the LIBS technique could be a prospect method for determination of elemental composition in the cement production industries.

A carbon dioxide (CO2) sensor is developed using quartz enhanced photoacoustic spectroscopy (QEPAS) with a 2.0 μm distributed feedback diode laser. The detection is based on a 2f wavelength-modulation spectroscopy approach by dithering and scanning the laser current. The laser modulation depth is optimized at normal atmosphere pressure and room temperature. The influence of the H2O presence in the sample gas mixture on the CO2 sensor performance is also investigated. The results show that, with 1% CO2 concentration, the H2O in the concentration ranges of 0 to 0.2% has an effect on the CO2 signal amplitude and phase, and the largest amplitude difference is ~2.1 times. When the H2O concentration is over 0.2%, the CO2 signal amplitude is saturated and remains steady. Atmospheric CO2 concentration is well measured using the optimal sensor parameters. Benefiting from the strong absorption line intensity at 4989.97 cm(-1), a detection limit of 19 ppm (1σ, 300 ms averaging time) is achieved, which corresponds to a normalized noise equivalent absorption coefficient of 4.71 × 10(-9) cm(-1) · W · Hz(-1/2).

Objective: To estimate the median effective dose (EDs0) of oral administrated HX0969w, fospropofol disodium and propofol emulsion in rats, and to compare the sedative-hypnotic effects and safety of the three drugs., Methods: The ED50 of the three drugs were determined using sequential method. Thirty healthy adult Sprague-Dawley rats were divided into three groups randomly, being orally administered with HX0969w (n=10), fospropofol disodium (n=10) and propofol emulsion (n=10), respectively. The neurobehavioral performance of the rats was observed. The time of loss of forepaw righting reflex (LRR) and the time of recovery of forepaw righting reflex (RRR) were recorded., Results: The ED50 of oral HX0969w, fospropofol disodium and propofol emulsion were 96.5 mg/kg, 130.0 mg/kg and 113.8 mg/kg, respectively. HX0969w, fospropofol disodium and propofol emulsion had a mean LRR of (10.0 +/- 2.9) min,(7.5 +/- 2.8) min and (16.0 +/- 5.9) min; respectively; and a mean RRR of (66.9 +/- 21.5) min, (131.9 +/- 32.7) min and (198.9 +/- 110.0) min, respectively., Conclusion: HX0969w, fospropofol disodium and propofol emulsion can produce sedative-hypnotic effects and they are safe when administered by oral route. The two propofol prodrugs HX0969w and fospropofol disodium have shorter LRR than propofol emulsion. HX0969w also has a shorter RRR than fospropofol disodium and propofol emulsion.

Because of the poor accuracy of the commonly used Boltzmann plot method and double-line method, the Boltzmann-Maxwell distribution combined with the Saha-Eggert formula is proposed to improve the measurement accuracy of the plasma temperature; the simple algorithm for determining the linewidth of the emission line was established according to the relationship between the area and the peak value of the Gaussian formula, and the plasma electron density was calculated through the Stark broadening of the spectral lines; the method for identifying the plasma local thermal equilibrium (LTE) condition was established based on the McWhirter criterion. The experimental results show that with the increase in laser energy, the plasma temperature and electron density increase linearly; when the laser energy changes within 127~510 mJ, the plasma electron density changes in the range of 1.30532X10(17)~1.87322X10(17) cm(-3), the plasma temperature changes in the range of 12586~12957 K, and all the plasma generated in this experiment meets the LTE condition threshold according to the McWhirter criterion. For element Al, there exist relatively few observable lines at the same ionization state in the spectral region of the spectrometer, thus it is unable to use the Boltzmann plane method to calculate temperature. One hundred sets of Al plasma spectra were used for temperature measurement by employing the Saha-Boltzmann method and the relative standard deviation (RSD) value is 0.4%, and compared with 1.3% of the double line method, the accuracy has been substantially increased. The methods proposed can be used for rapid plasma temperature and electron density calculation, the LTE condition identification, and are valuable in studies such as free calibration, spectral effectiveness analysis, spectral temperature correction, the best collection location determination, LTE condition distribution in plasma, and so on.

Laser-induced breakdown spectroscopy (LIBS) as a rapid spectral analysis technology shows the outstanding application foreground and research value in coal quality on-line monitoring. In the practical application of this technology, the pulsed laser power fluctuation leads to the worse performance of long term stability, so a closed-loop feedback pulsed laser power locking device is set up, using laser power feedback signal to control and lock Nd:YAG laser output power. The laser power locking experiments are investigated in the same pre-set value with different splitting ratios, the different laser output power with the same proportion and the long time running modes. The results show that the beam split ration has little impact to the stability of the laser power, and the smaller split ration leads to the faster stabilization. This device can keep the output power of the pulsed laser being locked in the pre-set range for a long-term running, RSD values decrease from 2.4% of free-running to 1.1%.

In the present paper, the authors simply describe the principle of cavity ring-down spectroscopy (CRDS) measurement technology and introduce a threshold circuit, based on 555 timer IC (integrated circuit), applied to CRDS. And we verify the feasibility of the circuit. By means of changing the input resistor and input capacity, we analyzee the influence of threshold circuit characteristics on single ring-down event, and found that the greater the input capacitance, and the smaller the input impedance of circuit, the more serious the distortion of measurement of ring-down curve, especially when the resistance is less than 50 omega the ring-down time produces very big change. Then we collected and analyzed the C2H2 absorption signal at 6 531.7805 cm(-1) with different input resistance and input capacitance, and fitted the absorption line with Voigt profile. We found that the change of the input capacitance and resistance caused the distortion of fitting curve. Finally We give the optimal design of threshold circuit: the input impedance of the threshold circuit should be great, minimum of 100 omega, the capacitive reactance should be as small as possible, preferably below 1 nf, at the same time it should be ensured that the threshold of the circuit time constant is much smaller than ring-down time. The experiment research on CRDS technique application has important reference value to threshold circuit design.

In the present paper a theoretical description of the line shapes of frequency modulated noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) under saturated conditions is presented. Expressions for both Doppler broadened and Doppler free frequency modulated NICE-OHMS signals at their absorption and dispersion phases are given. The modulation frequency, saturation parameter and frequency modulation index are set to 384 MHz, 10 and 0.2, respectively in the simulation. Based on the simulated line shape curves, in the absorption detection phase there are four sub Doppler structures existing in the spectral envelope of absorption signals of two sidebands, and in the dispersion phase there are five sub-Doppler structures existing in the spectral envelope of dispersion signals of carrier and two sidebands. The sub-Doppler structure originates from the fact that two counter propagating waves interact with the same group of molecules and one can act as a detecting beam and the other can act as a pumping beam. Therefore the sub-Doppler structure can appear at laser carrier and sidebands frequency and their middle frequencies of carrier and sidebands. Since NICE-OHMS absorption signal is only related to the absorption of sidebands the small saturation parameters of two sidebands can not saturate the Doppler broadened signal too much Although the NICE-OHMS dispersion signal includes the dispersion of carrier and two sidebands, the amplitude of Doppler broadened signal does not have so much influence by saturation except for the Doppler free signal. Therefore NICE-OHMS technique is a good candidate for the high sensitive detection of gas medium but with high selectivity under the condition of low pressure. Finally the dependences of NICE-OHMS line shape on the detection phase and saturation parameter are simulated and analyzed, the results of which nicely agree with the existing experimental results. The researches on NICE-OHMS line shapes will help explain the phenomena of related experiment.

Frequency modulation spectroscopy (FMS) not only can be used to simultaneously measure the absorption and dispersion of atoms and molecules, but is the key technology of the noise immunity cavity enhanced optical heterodyne molecular spectroscopy (NICE-OHMS). The optical devices or the instability of output light polarization of the laser source will induce the residual amplitude modulation (RAM) in the FMS. RAM greatly limits the FMS technology application in trace gas detection, so the research on the RAM characteristics in the FMS has very important significance. Firstly, the lineshape of FMS without absorption was analyzed, and the impact factors on the RAM were acquired, then the influence of input and output polarization direction and electro-optical modulation (EOM) temperature was measured, respectively. They all have linear relationship with the RAM. The results verify the theoretical analysis and provide the basis for reducing the RAM and other related working.

In the present paper a phase controllable waveplate model was applied to the analysis of polarization maintaining fiber. Under the temperatures of 24 degrees C and 26.8 degrees C there is no residual amplitude modulation (RAM) existing in frequency modulation spectroscopy (FMS) when performing the measurement of fiber temperature dependence on the RAM. However, the temperature setting can not reduce the background long term drift and a servo feedback suggested by N. C. Wong and J. L. Hall can be used to actively reduce the RAM. The error signal for feedback is from the dispersion background signal of FMS without gas sample. The variation of RAM induced by the temperature changing of PM fiber is the main reason for the long term background drift of dispersion signal of FMS.

The present paper studied the impact of geometry dimensions, located angle and detection position of a quartz tuning fork (QTF) on the sensitivity of QEPAS system. Ten kinds of QTFs were employed to compare the sensitivity with each other, and the results show that the QTF with a wedge-shape top obtains a higher quality factor and turns to be 50% more sensitive than the ones with a regular cuboid top when detecting the water concentration at 7 306 cm-1. By studying the located angle of a QTF, it was found that it nearly makes no difference, but more noise is introduced when there is an angle phi between the laser beam and QTF. The optimal detection position of a QTF appears to be 3. 1 cm away from the bottom of the QTF under the case of the normal incidence. At last the influence of external contamination on the resonant frequency of a QTF is discussed. The authors found that the frequency of the QTF decreases along with the contamination increasing. A novel method to lower the frequency of the QTF is proposed. This may make a contribution to the QEPAS used in detecting trace gas with a low V-T relaxation.

A method is introduced about quantitative analysis of carbon in coal by LIBS (laser-induced breakdown spectroscopy) in the present paper, and it introduces data optimization technology and method based on spectral data integration, normalization and data screening processing to overcome the poor quality of precision in the analysis because of laser source energy fluctuation, self-absorption, sample surface roughness etc. It is showed that the standard deviation (SD) is less than 1.6% using the method to analyze C element content in coal, and this method also can be used for other element analysis for coal.

Self-designed identifying software for LIBS spectral line was introduced. Being integrated with LabVIEW, the soft ware can smooth spectral lines and pick peaks. The second difference and threshold methods were employed. Characteristic spectrum of several elements matches the NIST database, and realizes automatic spectral line identification and qualitative analysis of the basic composition of sample. This software can analyze spectrum handily and rapidly. It will be a useful tool for LIBS.

A technique about accurate measurement of oxygen content in coal in air environment using laser-induced breakdown spectroscopy (LIBS) is introduced in the present paper. Coal samples were excited by the laser, and plasma spectra were obtained. Combining internal standard method, temperature correction method and multi-line methods, the oxygen content of coal samples was precisely measured. The measurement precision is not less than 1.37% for oxygen content in coal analysis, so is satisfied for the requirement of coal-fired power plants in coal analysis. This method can be used in surveying, environmental protection, medicine, materials, archaeological and food safety, biochemical and metallurgy application.

For a better application of laser-induced breakdown spectroscopy (LIBS) to coal quality analysis, it is necessary to optimize the key parameters of the experimental LIBS-based device. The relationships between the key parameters and the signal-to-noise ratios (S/N) of the elemental emission lines in the plasma spectrum of the pulverized coal were studied, according to which the optimal parameters can be selected. Experimental results indicate that the optimal settings for our LIBS-based device are laser pulse energy = 120 mJ x Pulse(-1), delay time of spectrometer = 200 ns, laser focal point be located 3-5 mm underneath the sample surface, rotation speed of sample cell = 2.7 rev x min(-1), a narrow-band filter with center frequency of 1 064 nm and a diaphragm with center hole diameter of 1.5 mm be placed in the path of the laser beam. Quantitative analysis results of pulverized coal show that, by using the optimal LIBS-based device, the standard deviation (SD) of C has been reduced from 6.7% to 1.6%, while the relative standard deviation (RSD) of other trace elements has been reduced from 28% to 10%. As a result, th accuracy has been improved greatly.

The harmonic detection of methane at 6105.3694 cm(-1) was measured by use of a digital lock-in amplifier (SR830) remotely controlled by a computer. The programme was written by Visual Basic 6.0 because it has strong function and a friendly appearance. The experimental results are in agreement with theoretical analysis, which fully confirms that a better signal-to-noise ratio (SNR) can be achieved in the high-harmonics detection of trace gases by the digital lock-in amplifier. The method can be applicable to the highly sensitive detection of pollution gases.

The absorption coefficient alpha(v) of gas plays an important role in quantitative analysis of pollution gases and theoretical investigation of molecular parameter. In this paper we first analyze alpha(v) theoretically and present a calculation method. Then we analyze 2v3 band R3 manifold of pure CH4 and draw a conclusion that alpha(v0) decreases and the peak absorption kappa(v0) increases with increasing the pressure. When the pressure is <0.03 and >2 atm, we can calculate alpha(v0) using the Gaussian profile and Lorentzian profile respectively, and then analyze the relative error. Finally we analyze the peak absorption kappa(v0) at various pressures, then define the high-resolution area and high-sensitive area respectively when the pressure is <0.01 and >1 atm.