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Objective To determine the best collection time period of plasma which can be used for human COVID-19 immunoglobulin for intravenous injection through SARS-CoV-2-IgG change and neutralizing antibody distribution against different virus strain in representative mixed plasma before and after Omicron strain infection by ELISA and pseudovirus neutralization test. Methods An ELISA method for quantitative detection of SARS-CoV-2-IgG was established and its linear range,accuracy and precision was verified. SARS-CoV-2-IgG potency was detected in 25 convalescent plasma which were collected 20-40 days after confirmed Omicron infection, two groups of mixed plasma samples WP1 and WP2 were prepared according to the SARS-CoV-2-IgG results, and pseudovirus neutralization experiments with different virus strain (prototype strain, BA. 1,BA.2, BA.4/5, BF.7, BQ.1.1) were carried out to determine the distribution of neutralizing antibodies against different virus strain. SARS-CoV-2-IgG potency of representative mixed plasma collected from 14 plasma stations subordinate to the company before and after Omicron strain infection was detected, including Omicron convalescent plasma (OP) collected from different plasma stations from December 2022 to May 2023 and normal pool plasma (VN) feed in March 2023 which collected from March 2022 to December 2022. According to the results, the difference and the change rule with time of SARS-CoV-2-IgG before and after Omicron strain infection were analyzed. Results The linearity of SARS-CoV-2-IgG ranged from 6.25 to 200 EIU/mL, the accuracy in-batch ranged from 81.793% to 106.985%, the precision in-batch ranged from 1. 100% to 13.000%, and the total error in-batch ranged from 2.988% to 22.679%. The accuracy between batches ranged from 90.788%to 96.893%, the precision between batches ranged from 4.870% to 6.272%, and the total error between batches ranged from 9.192% to 15.399%. The results of pseudovirus neutralizing antibody showed that the potency of different virus strain neutralizing antibodies were in the order of prototype strain>BA.2>BA.4/5>BF.7≈ BQ.1.1>BA.1 and the correlation between WP1 and WP2 was high (Pearson r=0. 931 1, P=0.002 3) which indicated that the potency distribution of neutralizing antibodies of different virus strain in Omicron convalescent plasma was basically stable. Compared with the mixed convalescent plasma sample G128 collected in June 2022, the potency of Omicron neutralizing antibodies of WP series were significantly higher, the ratio of BA.2 antibody to prototype antibody increased from 26.9% (before infection) to 82.6%-87.5% (after infection). The results of VN series before Omicron infection were < 100 EIU/mL, and the results of OP series after Omicron infection showed that the plasma collected from the beginning of December 2022 was the peak of antibody in the same month,and then dropped sharply, entering a short plateau in February-March 2023 (potency was about 40% of the peak value),and then dropped sharply again in April (potency was about 20% of the peak value). Conclusion The potency and proportion of neutralizing antibody against Omicron subtype in convalescent plasma after COVID-19 Omicron strain infection increased significantly. IgG antibody of plasma donors in different regions reached its peak in the month of infection, then continued to dropped sharply. The best collection period of plasma that can be used for human COVID-19 immunoglobulin for intravenous injection was 1 to 2 months after infection.

This is an article in the field of process mineralogy. As the raw material of high-grade quartz products，higher-purity quartz sand has strict requirements on impurity elements．Besides that，the presence of inclusions has an important impact on its purity and performance．Based on this，the fluid inclusions in the vein quartz of western Hubei Province have been studied in detail by using X-ray diffraction，plasma atomic emission spectroscopy，optical microscope，micro temperature measurement and laser Raman spectroscopy．The results show that the content of SiO2 in the ore is beyond 99.9%，and the impurity elements are mainly Al and alkali metal elements．The inclusions in the quartz are single-phase saline solution inclusions，two-phase inclusions and containing CO2 three-phase inclusions．There is no solid inclusions in the ore．The size of inclusions is mainly concentrated in 5～25 μm．The uniform temperature is 160～270 ℃ and the salinity is less than 10.00% NaCl. As a result, the ore-forming fluid belongs to medium-low temperature and low salinity fluid.According to the analysis results of the inclusion characteristics, the ore can be used as a raw material for high-purity quartz sand after deep processing and purification．

Coal seam water injection can effectively inhibit gas gushing in the process of coal mining, and its inhibition effect mainly depends on the wetting characteristics of coal seam. The chemical structure of coal is one of the important factors affecting the wettability of coal. In order to study the relationship between the functional groups of medium and low rank coal and its wettability, the coal quality characteristics of typical medium and low rank coal samples were analyzed, and the parameters of different coal samples were obtained by Nicolet iN10 Fourier Transform microscopic infrared spectrometer. In this paper, the size of the contact Angle of deionized water at the solid-liquid-gas junction on the coal surface is used to characterize the wettability of coal. JC2000D contact Angle measuring instrument is used to obtain the contact Angle of different coal samples. Zeta potential can reflect wettability and ionization degree of coal surface functional groups, so as to establish the relationship between hydrophilic functional groups (hydroxyl functional groups, other oxygen-containing functional groups), contact Angle and Zeta potential of coal samples. The experimental results show that with the deepening of coal metamorphism, the strength of hydrophilic functional groups of coal samples decreases gradually, the peak height of hydrophilic functional groups of middle rank coal decreases by 0.13 compared with that of low rank coal, and the absorption peak area decreases by 58.91. The hydrophilic functional groups are negatively correlated with the contact Angle of coal samples, that is, the contact Angle decreases gradually with the increase of absorption peak intensity of hydrophilic functional groups, and the contact Angle decreases by 8.27 ° from middle rank coal samples to low rank coal samples. The relationship between hydrophilic functional groups and Zeta potential of coal samples shows a first-order exponential decay function, and the correlation coefficient is as high as 0.95. That is to say, the absolute value of Zeta potential increases gradually with the increase of absorption peak area of hydrophilic functional groups. The surface electronicity of coal samples is strong, and the hydrophilicity of coal is good. Among them, the hydroxyl functional group has a great influence on the wettability of coal, and the hydrogen bond formed by self-associating hydroxyl group is the main factor affecting the wettability of coal. Other oxygen-containing functional groups, such as carboxyl and ether bond hydrophilic functional groups, combine with water molecules under intermolecular force, showing strong vitality and improving the hydrophilicity of coal.

To explore the effects of different drying methods on lipid oxidation and volatile flavor components of fishery products, the corresponding experimental groups were prepared by hot-air drying, cold-air drying and traditional natural drying using fresh Spanish mackerel (Scomberomorus niphonius) as raw material. The moisture content, pH value, lipid content, acid value (AV), peroxide value (POV), malondialdehyde (MDA), fatty acid composition and volatile flavor components of raw materials and different dried samples were measured. The results showed that the moisture content of dried samples prepared by three drying methods was about 30% with the pH value above 6. The AV, POV and the contents of MDA in the cold-air drying group were lower than the other groups (P

[Objective] The accurate and rapid landslide susceptibility zoning method were studied in order to provide a reference for regional safety monitoring, and provide a scientific basis for the government to control landslide disasters. [Methods] The study was conducted in the Guichi District of Chizhou City, Anhui Province. The coupled model of gradient boosting decision tree-logistic regression (GBDT-LR) and an information value (I) model was used to determine the evaluation of regional landslide susceptibility. The model learns from the original samples and combines them to generate new simulation samples in order to enhance the fitting ability of the model to evaluate landslide susceptibility. The Borderline-Smote algorithm was used to solve the problem of sample data asymmetry. The slope unit divided by r.slopeunits software was selected as the minimum evaluation unit, and a total of 10 evaluation factors were selected: slope gradient, slope aspect, terrain curvature, profile curvature, plane curvature, topographic wetness index (TWI), topographic relief, normalized difference vegetation index (NDVI), distance from fault, and distance from river. The landslide susceptibility model was evaluated from three aspects: frequency ratio, density of landslide disaster points and hidden danger points, and the receiver operating characteristic (ROC) curve. [Results] The experimental results showed that the frequency ratio of the coupled model I-GBDT-LR was 10%, 13%, and 7% greater than that of the I, LR, and I-LR models, respectively. The density of landslide disaster points and hidden danger points in the high risk area increased by about 9, 11, and 7, respectively, and the ROC accuracy increased by about 10%, 9%, and 5%, respectively. [Conclusion] The accuracy of the coupled model was higher than that of the single model, and the accuracy of the coupled model proposed was higher than that of the I-LR coupled model, which provides an effective and new evaluation method for landslide susceptibility evaluation.

BackgroundMitochondrial dynamin-related protein 1 (DRP1) regulates mitochondrial division and plays an important role in maintaining hepatocyte function. However, the role of DRP1 in cadmium exposure-induced maternal liver damage in pregnant mice remains unclear. ObjectiveTo investigate the role and mechanism of DRP1 in maternal liver damage induced by cadmium exposure during pregnancy.MethodsThis study consisted of animal experiments and cell experiments. (1) Animal experiments. Mice at 14 days of gestation were randomly divided into three groups: a control group, a low-dose cadmium group (LCd group: 2.5 mg·kg−1), and a high-dose cadmium group (HCd group: 5 mg·kg−1). The pregnant mice were intraperitoneally injected with cadmium chloride (CdCl2) for 6 and 24 h in the next morning. The weights of pregnant mice, uterus, maternal liver, and fetal mice were recorded after sacrifice. Serum and liver of pregnant mice were collected, the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum were detected, and liver tissues were stained with HE to observe changes in liver function and liver tissue structure. The expressions of oxidative phosphorylation-related proteins, hypoxia inducible factor-1α (HIF-1α) and DRP1 proteins in liver of pregnant mice were detected by Western blotting. (2) Cell experiments. AML12 cells were treated with CdCl2 (10 μmol·L−1) for 0, 2, 6, 12, and 24 h. The expressions of oxidative phosphorylation-related proteins, DRP1, and hypoxia inducible factor-1α (HIF-1α) proteins were detected. AML12 cells were pretreated with DRP1 inhibitor Mdivi-1 for 1 h and then CdCl2 (10 μmol·L−1) for 12 h to detect the expression of oxidative phosphorylation-related proteins and DRP1 protein. AML12 cells were treated with Hif-1α siRNA for 48 h and CdCl2 (10 μmol·L−1) for 6 h to detect the expression of HIF-1α and DRP1 proteins. ResultsThe results of animal experiments showed that cadmium exposure in pregnant mice had no effects on maternal liver weight and liver coefficient. However, the histomorphological changes and necrosis in hepatocytes were observed. Compared with the control group, the serum ALT and AST levels of pregnant mice in the LCd group were significantly increased after 6 h (P＜0.05), and the levels in the HCd group were significantly increased after 6 and 24 h (P＜0.05). Cadmium exposure during pregnancy significantly up-regulated HIF-1α and DRP1 expressions and down-regulated the expressions of oxidative phosphorylation-related proteins in maternal livers. In vitro cell experiments showed that the expressions of oxidative phosphorylation-related proteins was significantly decreased and HIF-1α and DRP1 protein expressions were significantly increased in the AML12 cells treated with CdCl2 for 6 h. Mdivi-1 pretreatment significantly antagonized the inhibitory effect of cadmium on the expressions of oxidative phosphorylation-related proteins in AML12 cells, while Hif-1α siRNA pretreatment significantly antagonized the up-regulative effect of cadmium on DRP1 expression in AML12 cells. ConclusionCadmium exposure in pregnant mice may up-regulate DRP1 expression by activating HIF-1α signaling, then inhibit oxidative phosphorylation level of hepatic cells, and ultimately lead to maternal liver damage.

As an important new non-metallic electronic material，higher-purity quartz sand has high requirements on impurity elements in inclusions of raw materials．Besides that ，the presence of inclusions has an important impact on its purity and performance．Based on this，the fluid inclusions in the vein quartz abroad have been studied in detail by using optical microscope, X-ray diffraction，plasma atomic emission spectroscopy，micro temperature measurement and laser Raman spectroscopy．The results show that the content of SiO2 in the ore is beyond 99.9%，and the impurity elements are mainly Al，alkali metal elements and Fe．The inclusions in the quartz are single-phase saline solution inclusions，two-phase saline solution inclusions and containing CO2 three-phase inclusions．There is no solid inclusions in the ore．The uniform temperatures of the two samples inclusions are 120～270℃ and 90～140℃．As a result，the deposit of the ore is medium-low temperature hydrothermal metamorphic quartzite．The raw ore can be used as the raw material of higher purity quartz sand after inclusion elimination and impurity reduction.

Objective: To explore the effects of different concentrations of Rosa roxburghii Tratt powder on antioxidant stress injury of skeletal muscle in overtrained rats. Methods: The rats were divided into the control group (C group), exercise group (HT group), low concentration Rosa roxburghii Tratt powder exercise group (L-HT group) and high concentration Rosa roxburghii Tratt powder exercise group (H-HT group). HT, L-HT and H-HT groups underwent treadmill training with increasing load for 6 weeks, respectively. During the training, L-HT group and H-HT group were intragastrically administered with 20 and 50 mg/mL Rosa roxburghii Tratt powder solution at the dose of 20 mL·kg−1·d−1, respectively. Group C and HT were given the same dose of saline. The samples collected 24 hours after last training were used to measure serum creatine kinase (CK), interleukin -1β (IL-1β) and tumor necrosis factor-α (TNF-α). The activities of superoxide dismutase (SOD) and the contents of malondialdehyde (MDA) and glutathione (GSH) in skeletal muscle were determined. The expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1(HO-1), B cell lymphoma factor-2 (Bcl-2) and Bcl-2-related X protein(Bax) in skeletal muscle was detected. Results: Compared with the HT group, the activity of CK decreased (P

Shielded Metal Arc Welding (SMAW) is always used for the vertical welding of inner wall of LNG storage tanks in China, and there has been no successful case for the application of automatic welding technology to vertical welding so far. In this paper, an automatic Flux Cored Arc Welding (FCAW) technology with multi-layer, filament, short arc, circumferential swing and short pause on both sides of the groove was proposed through the automatic welding test of vertical welds of 9%Ni steel plates. Then, tests on mechanical properties were conducted for the welds made with this technology. The results show that the tensile, bending and low-temperature impact properties of the specimens can meet the requirements of relevant standards. In particular, the low-temperature Charpy impact energy of the heat affected area is 17.6% higher than that of SMAW. In addition, the vertical FCAW was applied to a 16×104 m3 LNG tank in a LNG receiving terminal of China, with the welding efficiency increased by 52% and the welding repair rate reduced by 2% in comparison to SMAW. In addition, the tank passed the hydrostatic test, kept stable in trial run, and was put into operation. So, the research results could provide some theoretical guidance and practical basis for the promotion of automatic welding for vertical welds of inner LNG storage tank in the future.

With the developments of exploration and production of natural gas in the Dongsheng gas field of Hangjinqi area, northern part of Ordos Basin, industrial valued helium has been discovered in this area. Natural gases from 166 wells in the Dongsheng gas field were analyzed in this study and results show that the helium contents of these gases range from 0.045% to 0.487%, with an average value of 0.118%, indicating industrial value for the helium resource. Two basement-faults developed zones of Duguijiahan and Shiguhao in the center of the gas field have relative higher content of helium, with an average value higher than 0.1%, indicating a great exploration potential. The average helium contents decrease from the lower stratum (the first member of Xiashihezi Formation, P1x1) to the upper stratum (the third member of Xiashihezi Formation, P1x3), indicating that the P1x1 and P1x2 are potential targets for helium exploration and development. According to helium isotopic compositions, helium in the Dongsheng gas field has of a typical crust source, mainly from Archean-Proterozoic metamorphic rock-granite series in the basement. It is clear that helium distribution in the Dongsheng gas field was controlled by both basement lithofacies and deep fractures. Helium is enriched mainly along deep basement fractures such as Borjianghaizi and Wulanjilinmiao, and at the intersection of second-level fractures communicating helium source and fourth-level faults being migration pathways, and in the areas of Archean-Proterozoic metamorphic rock-granite series basement distribution. The variation of helium content with gas well production performance in short and medium term of key natural gas wells in the Dongsheng gas field showed that the helium contents in natural gases are stable in a relatively long term. The proved helium reserves are 244.4×106 m3 and the 3P reserves are approaching 830.4×106 m3 by volume method. Thus, the Dongsheng gas field is considered as the first supergiant helium-rich gas field in China. It is suggested that the Dongsheng gas field in the Ordos Basin should be regarded as a pilot test area for the development and utilization of helium resources, and the feasibility of building helium strategic reserve base should be accelerated. The research on helium accumulation mechanism, resource potential evaluation and comprehensive utilization of helium and other associated resources in natural gas should be strengthened in major oil and gas bearing basins, in order to guide the exploration, development and comprehensive utilization of helium resources.

The influence of different parameters on the offset tracking calculation results was analyzed. Then, the offset tracking method based on texture features was added to the offset tracking tool of SNAP8.0. Two offset tracking methods were combined to process the Sentinel-1 ascending and descending data. Two-dimensional deformation of the open-pit mine were calculated according to the geometry of ascending and descending observation. The results show that there are 6 large gradient deformation areas in waste dump, mining area, and stripping area. Vertical and east-west deformation ranges from -42.41 m to 40.71 m and -50.41 m to 42.80 m, respectively. In stripping area, vertical and east-west deformation reaches the maximum, which is -42.41 m and -50.41 m, respectively. The identified large gradient deformation is mainly located in the areas with frequent mining and dumping operations, Therefore, SAR offset tracking technology can effectively monitor the deformation in operation area of open-pit mine, so as to ensure the safe production and life in mining area.

High resolution remote sensing images play an important role in landslide recognition. In order to solve the problems of diverse data, complex algorithms, redundant features, and insufficient research on the specific texture characteristics of a single landslide, Gabor filtering was used for texture feature extraction and fusion of spectral features using Support Vector Machine to achieve landslide extraction. First, multi-scale and multi-direction Gabor transformation is carried out on the landslide image. Then, the Gabor features of different scales in the same direction are fused to obtain the multi-directional features. Finally, the multi-directional Gabor features are filtered at the maximum to form the multi-scale and multi-directional Gabor texture features. The results show that, compared with the local binary model and local spatial autocorrelation, the texture analysis method in this paper has the best effect on landslide extraction and a high extraction accuracy.

Objective To investigate the clinical phenotype and genotype manifestations of autosomal recessive hereditary spastic ataxia 2 (SPAX2), to help physicians recognize this disease. Methods and Results A 35-year-old male patient presented with postural tremors, ataxia, hyperreflexia and then got worse progressively. Sanger sequencing found a homozygous missense mutation in the exon 13 c.1089T > G (p.Ile363Met) of KIF1C gene. It came from his parents respectively and was consistent with the autosomal recessive genetic law. The patient was clearly diagnosed as SPAX2, and his family was diagnosed as SPAX2 pedigree. Conclusions KIF1C-related SPAX2 may be considered as a candidate diagnosis for adolescent patients with postural tremor, ataxia and hyperreflexia. DOI: 10.3969/j.issn.1672-6731.2019.06.008

Objective To summarize phenotype, treatment principles and prognosis of 4 patients from 2 pedigrees with late-onset methylmalonic aciduria (MMA) and homocystinuria cobalamin C (cblC) type, so as to explore the pathophysiological mechanism of this disease. Methods and Results Exome sequencing was applied to rapidly diagnose 2 pedigrees of late-onset MMA and homocystinuria cblC type. The MMACHC gene mutations of the sisters in pedigree 1 were exon 4 c.482G > A (p.Arg161Gln) and c.615C > A (p.Tyr205X). Their parents carried the gene mutation respectively. The proband presented intelligence deterioration, spastic motor dysfunction of lower limbs and epilepsy. The younger sister presented axonal peripheral neuropathy and optic nerve atrophy, while the mental retardation was mild. For the brother and sister in pedigree 2, c.440_441del (p.Gly147fs) and c.482G > A (p.Arg161Gln) in exon 4 of MMACHC gene were identified which came from their parents respectively. The proband presented mental retardation and behavior disorder, weakness of lower limbs with pyramidal sign, and myelinated and axonal mixed peripheral neuropathy. His younger sister had similar symptoms and suffered earlier. After treated by vitamin B12, folic acid and levocarnitine for 6 months, all patients showed intelligence improved and seizures controlled, while still suffered from different degrees of dyskinesia of lower limbs. Conclusions The clinical symptoms of late-onset MMA and homocystinuria cblC type are complex and variable. Cerebral cortex, pyramidal system, extrapyramidal system and peripheral nerve could be widely involved. Target region gene capture combined with next-generation sequencing technology can be used to diagnose the disease rapidly, and early diagnosis and treatment are crucial to improve the prognosis. DOI: 10.3969/j.issn.1672-6731.2019.06.007

BACKGROUND Lithium isotopes are widely used in various fields of earth and planetary science. Accurate determination of the lithium isotopic ratio is the premise of tracing various natural processes. However, there are large deviations in the measured values of lithium isotopic reference materials reported by international laboratories. For example, the reported seawater δ7Li test value differs by 5‰. To avoid this fractionation, laboratories employ their own empirical recovery values obtained from recovery tests rather than a theoretical one. OBJECTIVES To investigate the reasons of this huge discrepancy and get an instructively theoretical value, so as to appraise Li fractionation during ion exchange and purification processes. METHODS Based on the theory of ion exchange, this study uses the normal distribution function to fit the leaching curve, and theoretically calculates the theoretical value of lithium isotope fractionation caused by the ion exchange purification process, which is independent of MC-ICP-MS detection. However, it has a direct impact on the accuracy of lithium isotope testing. On this basis, the relative recovery is defined to monitor lithium isotope fractionation. RESULTS The fitting calculations show that only when recovery is higher than 99.8%, there would be no observable Li isotope fractionation caused by ion exchange and purification processes. At present, laboratories in the world mainly judge whether or not isotope fractionation occurs in the separation process by absolute recovery or relative recovery. Due to the space charge effect of the test, the absolute recovery is easily overestimated, and > 99% of relative recovery does not reach the theoretically calculated one, indicating that the deviation of the test results of the same reference material in each laboratory is most likely due to ion exchange. CONCLUSIONS It is proposed that for each sample, it is only necessary to separately measure the lithium content in the receiving interval and the intervals before and after the ion exchange processes, and the obtained relative recovery value is compared with the theoretical value to determine whether observable lithium isotopic fractionation occurs during the separation and purification processes.

Objective To estimate the accuracy and stability of capillary electrophoresis fragment analysis and clone sequencing in detecting dynamic mutations of spinocerebellar ataxia (SCA). Methods Capillary electrophoresis fragment analysis and clone sequencing were used in detecting trinucleotide repeated sequence of 14 SCA patients (3 cases of SCA2, 2 cases of SCA7, 7 cases of SCA8 and 2 cases of SCA17). Results Capillary electrophoresis fragment analysis of 3 SCA2 cases showed the expanded cytosine-adenine-guanine (CAG) repeats were 31, 30 and 32, and the copy numbers of 3 clone sequencing for 3 colonies in each case were 37/40/40, 37/38/39 and 38/39/40 respectively. Capillary electrophoresis fragment analysis of 2 SCA7 cases showed the expanded CAG repeats were 57 and 34, and the copy numbers of repeats were 69, 74, 75 in 3 colonies of one case, and was 45 in the other case. For the 7 SCA8 cases with the expanded cytosine-thymine-adenine (CTA)/cytosine-thymine-guanine (CTG) repeats of 99, 111, 104, 92, 89, 104 and 75, the results of clone sequencing were 97, 116, 104, 90, 90, 102 and 76 respectively. For 2 SCA17 cases with the short/expanded CAG repeats of 37/50 and 36/45, the results of clone sequencing were 51/50/52 and 45/44 for 3 and 2 colonies. Conclusions Although the higher mobility of polymerase chain reaction (PCR) products containing dynamic mutation in the capillary electrophoresis fragment analysis might cause the deviation for analysis of copy numbers, the deviation was predictable and the results were repeatable. The clone sequencing results showed obvious instability, especially for SCA2 and SCA7 genes, which might owing to their simple CAG repeats. Consequently, clone sequencing is not suited for detection of dynamic mutation, not to mention the quantitative criteria of dynamic mutation sequencing. DOI: 10.3969/j.issn.1672-6731.2018.03.008

Objective To investigate the clinical features and dynamic mutation of 10 cases with juvenile-onset Huntington's disease (HD). Methods The cytosine-adenine-guanine (CAG) repeats of IT15 gene were detected by polymerase chain reaction (PCR) and capillary electrophoresis in 272 individuals of 159 pedigrees with preliminary diagnosis of HD. The correlation between clinical features and expanded CAG repeats in the IT15 gene of 10 cases with juvenile-onset HD were studied carefully. Results Among 211 individuals carried expanded CAG repeats, 10 cases onset before 20 years of age. The predominant clinical manifestations were involuntary movement and cognitive impairment. The average age of onset was (12.50 ± 4.55) years, and the average CAG repeat number of IT15 gene was 63.70 ± 14.83. Pearson correlation analysis showed that the age of onset was significantly and negatively correlated with the CAG repeat number (r = - 0.865, P = 0.001). Conclusions 1) The juvenile?onset case of HD presented with different clinical features compared with adult - onset cases. The most common presentation is cognitive decline. 2) Analysis of CAG repeats of IT15 gene is necessary for the diagnosis of juvenile-onset case of HD with no family history. 3) The variability in age of onset is not completely explained by the effects of expanded CAG repeats of IT15 gene, which is more prominently for the juvenile?onset cases, therefore, it is suggested that other factors may modulate the age of onset. DOI: 10.3969/j.issn.1672-6731.2017.08.008

Objective To make the diagnosis for a patient presented with head tremor and cerebellar atrophy by integrating clinical features and accessory examination with genetic testing and to explore the interpretation of genetic testing results. Methods A 30-year-old male patient's medical information, clinical pheontype, family history and accessory examinations were collected. The next?generation sequencing (NGS) of exons in 3994 causative genes of Mendelian inheritance diseases and the family tree verification were carried out. China Human Phenotype Ontology (CHPO), Phenomizer, Ensembl and Online Mendelian Inheritance in Man (OMIM) database were used to interpret the genetic test results. Results The patient carried heterozygous mutation of spinocerebellar ataxia type 19 (SCA19) related KCND3 gene c.1057A > G (p. Ser353Gly), but his parents did not carry this mutation. The patient also carried heterozygous mutation of parkinsonism type 20 (PARK20) related SYNJ1 gene c.4436C > T (p.Thr1479Ile) which was also seen in his mother. Phenotypic similarity analysis showed the patient's phenotype was correspond with the phenotype of SCA19, and the variation locus of KCND3 gene c.1057A > G was highly conservative with homologous gene in different species. Conclusions By means of the integration of clinical phenotype with the result of genetic test, KCND3 gene c.1057A > G (p.Ser353Gly) carried in the patient is the pathogenic mutation. DOI: 10.3969/j.issn.1672-6731.2017.07.007

Stimulation principles, construction techniques, equipment requirements and technical features of liquid carbon dioxide fracturing were summarized, and the existing problems and development trend of this technology were discussed. Compared with the conventional hydraulic fracturing technology, it has several advantages including high flowback, small damage in reservoir, outstanding stimulation effect and so on. There are five main problems existing in this technology: friction of liquid carbon dioxide is very high; liquid carbon dioxide has an extremely low viscosity, poor proppant carrying ability and a large amount of fluid loss, thus behaves poorly in fracturing; the phase behavior of carbon dioxide is very complex in the process of fracturing, it is hard to realize accurate prediction and control for phase transition of carbon dioxide; fracturing equipments, especially blenders have obvious defects and should be improved further; computational methods for operation parameters in liquid carbon dioxide fracturing is still lacking. Supercritical carbon dioxide fracturing technology succeeds almost all the advantages of traditional liquid carbon dioxide fracturing technology, and has a better stimulation effect, smaller pump pressure and fewer requirements for blenders, thus is the trend in carbon dioxide fracturing. Key words: unconventional resources, fracturing with carbon dioxide, fracturing with supercritical carbon dioxide, reservoir stimulation, phase change

Background Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant genetic disease characterized by cerebellar ataxia, ophthalmoplegia, slow saccade, hyporeflexia, action tremor, cognitive decline and peripheral neuropathy. The brain MRI shows obvious atrophy of cerebellum and brainstem, indicating typical change of olivopontocerebellar atrophy. SCA2 is caused by an expanded cytosine-adenine-guanine (CAG) trinucleotide repeat in the encoding region of ATXN2. The normal CAG repeats range from 13 to 31, and ataxic phenotype occurs when the repeats are more than 34. This study focused on the clinical and imaging features of 5 SCA2 families confirmed by genetic testing. The correlation between phenotype and genotype was analyzed. Methods The pathological CAG triplet repeat expansions of SCA1-3, 6, 7, 17 and dentatorubral-pallidoluysian atrophy (DRPLA) genes were analyzed in the probands of 708 autosomal dominant SCA families and 119 sporadic SCA cases. The CAG repeat of ATXN2 gene was amplified by polymerase chain reaction (PCR) and agarose gel electrophoresis. Fragment analysis based on CEQ8000 sequencer were applied to analyze expanded alleles. Results Expanded CAG repeats of ATXN2 gene were detected in 45 probands of SCA2 families. Most of the patients manifested with the typical clinical features of SCA2 such as cerebellar ataxia, ophthalmoplegia, slow saccade and hyporeflexia. Some of them also associated with action tremor. The brain MRI showed obvious atrophy of cerebellum and brainstem. The correlation between clinical features and CAG repeat of ATXN2 gene wasstudied carefully in 5 families. Conclusion Genetic analysis provides the basis for the diagnosis of SCA2. Clinical and neuroimaging features are very helpful in the diagnosis and differential diagnosis of this disease. For the identification of cases carrying intermediate allele, it is important to combine clinical, imaging features with dynamic mutation analysis in the affected cases within the family.

Background and objective Tumor suppressor in lung cancer-1 (TSLC1) belongs to immunoglobulin superfamily of cell adhesion molecule and differentially expressed in adenocarcinoma of the lung (4.1B)belongs to NF2/ERM/4.1 protein superfamily. They may suppress carcinogenesis via construction of the adjacent cell adhesion stability. The aim of this study is to detect the expressions of TSLC1 and 4.1B in non-small cell lung cancer and the clinical pathological significances. Methods The expressions of TSLC1 and 4.1B were detected by RT-PCR in 52 cases of non-small cell lung cancer and corresponding adjacent cancer lung tissues. Results The expressions of TSLC1 and 4.1B in cancer tissues were significantly lower than that in adjacent cancer lung tissues (0.349±0.008 vs 0.555±0.010; 0.209±0.040 vs 0.721±0.071) (P < 0.01). The expressions of TSLC1 and 4.1B showed a significant correlation with cancer differentiation and TNM staging (P < 0.05), but not with gender, age and pathological type (P > 0.05). The expressions of TSLC1 and 4.1B were positively correlated (r=0.471, P < 0.001). Conclusion Down-regulated expressions of TSLC1 and 4.1B in non-small cell lung cancer, both may participate in a cascade of non-small cell lung cancer occurrence and development. TSLC1 and 4.1B are promising targets for non-small cell lung cancer diagnosis and treatment.

Objective To analyze the relevant risk factors for intracranial infection after craniotomy for resection of skull base neoplasms. Methods The clinical data of 159 patients with skull base neoplasms who underwent craniotomy from May 2010 to January 2020 in The Second Affiliated Hospital of Anhui Medical University were analyzed retrospectively. The relevant risk factors for intracranial infection were analyzed by univariate and multivariate forward Logistic regression. Results Postoperative intracranial infection occurred in 81 out of 159 patients, the infection rate was 50.94%. Multivariate forward Logistic regression analysis showed the operation time was ≥5 h (OR = 3.438, 95%CI: 1.371-8.625; P = 0.008), blood loss ≥ 400 ml (OR = 2.308, 95%CI: 1.115-4.777; P = 0.024), frontal sinus or mastoid air chamber breach (OR = 16.817, 95%CI: 3.689-76.658; P = 0.000) were the risk factors for intracranial infection after craniotomy for resection of skull base neoplasms. Conclusions There was a higher risk of intracranial infection after craniotomy for resection of skull base neoplasms in patients who had long operation time, more intraoperative blood loss as well as frontal sinus or mastoid air chamber breach. It is necessary to adopt effective prevention and control measures to reduce the risk of intracranial infection. [ABSTRACT FROM AUTHOR]

Based on air quality data from dense local micro-stations and sparse national stations, and meteorological data, this study examined the temporal and spatial patterns of air pollution during the Spring Festival in Xiangyang using high-frequency spatial analysis, correlation analysis, and pollutant concentration comparison. The implementation effect of a policy banning fireworks and firecrackers during the Spring Festival was evaluated. The results showed that during the Spring Festival in 2018, the weather in Xiangyang was relatively stable, and the air quality was generally poor. Owing to the influence of fireworks and firecrackers set off from New Year's Eve to the first day of the Lunar New Year in the peripheral areas of Xiangyang, the air pollution condition shifted from mild to severe. The concentrations of PM2.5 and PM10 increased gradually from 19:00 on New Year's Eve, rose linearly after 00:00 on the first day of the Lunar New Year, and then reached a peak during the Spring Festival at 08:00. During this period, the concentrations of SO2 and NO2 also increased significantly, whereas that of CO had no obvious regularity. During the Spring Festival, the spatial distribution patterns of PM2.5 and PM10 daily average concentrations showed a moderate or higher pollution trend of "high in the South and low in the North" on New Year's Eve and the second to fifth days of the Lunar New Year, with Hanjiang and Tangbai Rivers as the boundaries. On the first and sixth days of the Lunar New Year, air pollutants covered almost all of Xiangyang. The setting off of fireworks and firecrackers in the surrounding areas is the primary cause of the heavily polluted weather from New Year's Eve to the first day of the Lunar New Year, and until the fourth day. Traffic exhaust, road dust, and cooking fumes remain significant sources of air pollutants in Xiangyang during the Spring Festival. The characteristic geographical environment and variable meteorological elements are important factors that cause air pollution. Owing to the continuous adoption of air pollution prevention and control policies over the past four years, the overall air pollution situation has improved in Xiangyang. The scope of the firework bans was gradually expanded, thus effectively improving the overall air quality. Compared with research on urban air pollution using a small number of monitoring stations, the application of a high-density air quality monitoring network can describe in detail the spatio-temporal distribution characteristics of urban air pollution on a local scale. Accordingly, increasing the frequency of the spatial analysis of air pollution can allow for the deduction of the specific evolutionary process of air pollution in space. Particularly in special periods or polluted weather, a precise understanding of the spatio-temporal evolution of air pollution can provide an important basis and reference for the prevention and control of urban air pollution.

Based on the loop formation of three-dimensional fabric, three-dimensional fabric sweater can be divided into three types, floating, tuck class, loop formation. By using sweater yarn, different materials, different morphology and different structures, woven different forms three-dimensional fabric Comparison with experimental method ,research and analysis from the yarn to study the effect on three - dimensional fabric . Sweater yarn structure are the greatest impacted the three -dimensional fabric pattern and texture of fabric ,followed by the thickness of the sweater yarn ,materials of yarn and yarn twist, have main effect to the performance and feel of fabric sweater. Only smooth, uniform thickness and flexibility yarn can be good showing a better three-dimensional fabric effects. It provides a theoretical basis for designers. [ABSTRACT FROM AUTHOR]

Taking the China rice/wheat FACE ( Free-Air Carbon Dioxide Enrichment) as a platform, this paper studied the effects of elevated CO2 on the NH4+ -N and NO3--N contents at different depths of paddy soil in rice season. Under elevated CO2, the NH4+ -N content in plough layer increased at early growth stage but decreased at late growth stage, and the soil NO3- -N content at the depths 5, 15, 30, 60, and 90 cm increased by 46. 5%, 36. 8%, 23. 3%, 103. 7%, and 42. 7%, respectively, with a significant increase occurred at the depths 60 cm (P<0. 01) and 90 cm (P< 0. 05), compared with the control. [ABSTRACT FROM AUTHOR]

Background Pre-pregnancy obesity can have a range of effects on both the mother and the fetus, possibly due to abnormalities in maternal-fetal metabolism. Therefore, exploring the mechanisms is essential to improve fetal prognosis. Objective To investigate the alterations of factors associated with obesity and glucose metabolism in the placentas of pregnant women with different BMI levels before pregnancy. Methods A total of 100 singleton pregnant women who delivered in Beijing Shijitan Hospital, Capital Medical University in 2019 were selected as the study subjects. The clinical data were collected based on the electronic medical record system. The subjects were divided into the low/normal body mass group (n=57) and overweight/obese group (n=43) based on their pre-pregnancy body mass. The expression of long non-coding RNA metastasis-associated Lung adenocarcinoma transcript 1 (LncRNA MALAT1), serum amyloid A3 (SAA3), and interleukin 6 (IL-6) mRNA in placental tissue were measured using reverse transcription-polymerase chain reaction. Results The age of the subjects ranged from 22 to 43 years, with an average age of (32.7±4.2) years, including 61 primiparas, 21 with gestational diabetes mellitus (GDM), 14 with low body mass, 43 with normal body mass, 26 with overweight, and 17 with obese. The proportion of GDM and neonatal body mass in the overweight/obese group was higher than that in the low/normal body mass group, and the weight gain during pregnancy was lower than that in the low/normal body mass group, with statistically significant differences (P

In the context of population ageing, the number of elderly patients with dementia is increasing day by day. This disease seriously affects the quality of life of the elderly and causes huge burdens and pressures on families and society. At this stage, issues such as low level of attention at the national and social levels, weak ability of active screening and identification, high treatment and care costs, and fragmented social service system are prominent in the elderly dementia. It is imperative to actively explore the construction of a care system that covers the entire life cycle of dementia in the elderly, which is composed of multiple welfare subjects such as the government, community, family, market, and civil society organizations. Based on the practice of the full-cycle support project for elderly patients with dementia and their families in Beijing X Hospital, the research takes the theory of welfare pluralism as the framework, and constructs the implementation path and mechanism of the welfare pluralism care system for the elderly with dementia through action research. Based on the portrayal of the reality of the elderly with dementia, health social workers break through the shortcomings of the original medical social work service, such as the single service object, the confinement of the service place, the disconnection of the needs of patients with different disease cycles, and the poor effect of the resource link, etc., turn to the perspective of health social work to use the method of action research to try to break the situation from four directions: in the stage of early detection of dementia, we can clarify the responsibilities of service subjects and maximize service effectiveness; in the stage of early treatment of dementia, we can break down barriers between service subjects and realize the value of resources flow; in the stage of self-management of patients with dementia, we can mobilize the subjective initiative of service subjects to achieve positive transformation of target group; in the dementia friendly advocacy stage, we can respond to the internal needs of service subjects and achieve sustainable development of the care system.

Background Pregnancy and vaginal delivery are important factors leading to pelvic floor dysfunction (PFD) in women, manifested as pelvic organ prolapse (POP), stress urinary incontinence (SUI), and sexual dysfunction. Postpartum pelvic floor function rehabilitation has become a research hotspot in recent years. Stimulating the pelvic floor muscle groups through active exercise and passive contraction can improve detrusor stability and levator muscle function to prevent and treat PFD. Objective To investigate the clinical value of biofeedback electrical stimulation combined with pelvic floor muscle training (PFMT) therapy in the rehabilitation of pelvic floor function after vaginal delivery through a clinical controlled study. Methods Postpartum women with PFD after delivery implemented in Department of Obstetrics and Gynecology, Beijing Shijitan Hospital Affiliated to Capital Medical University from January 2020 to January 2022 were selected as the research subjects, and divided into the observation group and the control group using a random number table method. The observation group was treated with biofeedback electrical stimulation combined with PFMT, while the control group was treated with PFMT alone. The muscle strength of the pelvic floor class Ⅰ and class Ⅱ muscle fibers, the ratio of SUI and POP level of the two groups before and after treatment; postpartum PFMT situation; scores of Pelvic Floor Dysfunction Questionnaire (PFDI-20), Pelvic Floor Impact Questionnaire-7 (PFIQ-7), and International Consultation on Incontinence Questionnaire Urinary Incontinence Short Form (ICI-Q-SF) before and at 3 and 6 months after the treatment. Results A total of 327 cases were included in the observation group and 343 cases in the control group. After the treatment, the strength recovery of type Ⅰ and Ⅱ muscle fibers in the observation group was better than the control group (P0.05). The proportion of PFMT frequency≥5 times/week in the observation group was higher than that in the control group at 3 months and 6 months after treatment (P

As the acceleration of urbanization and population aging in China, the prevalence of various chronic diseases among residents is increasing, the prevention and control of various chronic diseases in the medical care and public health fields are becoming more and more severe. As one of the important treatment modalities, physical activity referral schemes (PARS) have achieved remarkable results in the prevention and treatment of chronic diseases abroad, among which PARS in Australia has become a model for "treatment + co-treatment". This study overviews the formation and development of PARS in Australia comprehensively, summarizes and analyzes its implementation experience. It is recommended to build a sharing and interaction mechanism of general practice and sports co-treatment in China in the context of the current development situation of medical care and sports rehabilitation in China from the following aspects: building a referral structure with general practice as the core, promoting the synergistic governance of general practice and sports co-treatment; improving the personnel training system of general practice and exercise physiology, accelerating the training of medical exercise and health coaches; promoting the innovation of the service system, accelerating the construction of scientific process of general practice and sports co-treatment; exerting the advantages of the Internet vigorously to build a data and information platform of general practice and sports co-treatment.

For studying the crevice corrosion behavior and mechanism of Q235 carbon steel under different crevice widths and environmental temperatures, wire beam electrode (WBE) technology and electrochemical impedance spectroscopy (EIS) technology were used to study the differences in current density, polarization resistance, and corrosion morphology of wire beam electrodes. Results showed that when the crevice width was greater than 0.1 mm, the corrosion characteristics of the crevice were not obvious. When the crevice width was 0.1 mm, the maximum current density differences of carbon steel during the initial immersion at 25, 40, and 60 ℃ were 1.24, 19.90, and 7.20 μA/cm2, respectively, while the maximum current density differences after 72 h of immersion were only 41.9%, 4.2%, and 11.9% of the initial immersions. In addition, the polarity conversion phenomenon of current occurred both inside and outside the crevice, indicating that Q235 carbon steel gradually transformed from local corrosion to uniform corrosion with the prolongation of immersion time. Moreover, increasing temperature could enhance the trend of crevice corrosion, and the causes of the most serious corrosion outside the crevice were insufficient soaking time and an increase in solution resistance drop. In general, FeOOH participating in the cathodic reaction caused the electrode to change from the anode to the cathode, while the dissolution reaction of the metal caused the electrode properties changing from the cathode to the anode.

In order to investigate the effect of different copper surface state on the protection performance of triazole click-assembly film on Cu in circulating cooling water of power plants，the triazole inhibition films (CuMA-PR，Cu2OMA-PR，CuOMA-PR) were prepared via an in-situ click assembling reaction using p-toluenesulfonyl azide (MA) and propionic acid (PR) as assembly units on different copper surface state.Corrosion inhibition performance of the triazole inhibition films on copper substrate was evaluated by electrochemical method，corrosion coupon testing，SEM characterization and antibacterial property analysis.At the same time，the protective effect of Cu2OMA-PR on copper substrate in the circulating cooling water system of power plant was investigated.Results showed that Cu2O surface state was the best for the formation of triazole inhibition film(Cu2OMA-PR).The Cu2OMA-PR exhibited an excellent corrosion inhibition and antibacterial property on copper substrate within 21 d.The average inhibition efficiency of Cu2OMA-PR for copper in 3 weeks was 85.4%.Besides，Cu2OMA-PR could also effectively inhibit the proliferation of various microbial communities.

As a new computing paradigm,edge computing provides computing and storage services at the edge of the network compared to traditional cloud computing model.It has the characteristics of high reliability and low latency.However,there are still some problems in privacy protection and data processing.As a distributed machine learning model,federated learning can well solve the problems of inconsistent data distribution and data privacy in edge computing scenarios,but it still faces challenges in equipment heterogeneity,data heterogeneity and communication,such as model offset,the convergence effect is poor,and the calculation results of some devices are lost.In order to solve the above problems,a federated learning optimization algorithm with dynamic weights(FedDw) is proposed,which focuses on the service quality of the equipment,reduces the heterogeneous impact caused by the participation of some equipments due to inconsistent training speed,and determines the proportion in the final mo-del aggregation according to the service quality,so as to ensure that the aggregation results are more robust in complex real situations.Through experiments,the two excellent federated learning algorithms,FedProx and Scaffold,are compared on the real data sets of 10 regional weather stations.The results show that the FedDw algorithm has better comprehensive performance.

Objective To investigate the incidence of pain in patients with Guillain-Barré syndrome （GBS） during acute phase and analyze its relationship with clinical features, clinical variants and anti-ganglioside antibodies in patients from Southwestern Shandong Province, aiming to explore the clinical significance of acute pain in GBS. Methods 226 patients with GBS were enrolled in this prospective observational clinical study. Clinical data were collected, and all patients were followed up for one year. The differences in clinical features, clinical variants and anti-ganglioside antibodies between patients with and without pain during acute phase were analyzed. Results Among 226 GBS patients, 121 were male and 105 were female. 45 patients （19.9%） had pain during acute phase, 46.5% （n = 105） developed antecedent infection, 82.7% （n = 187） experienced limb weakness and 51.8% （n = 117） had sensory deficits. 73.2% （145/198） presented with albuminocytological dissociation in the cerebrospinal fluid. 46.8% （96/205） were positive for anti-ganglioside antibody IgG. 44.7% （n = 101） were diagnosed with classic motor-sensory GBS and 39.4% （89/226） with pure motor GBS. The proportion of upper respiratory tract infection in GBS patients with pain was significantly lower than that in those without pain （P = 0.029）. There was no significant difference in clinical features, clinical variants and positive rate of anti-ganglioside antibodies between patients with and without pain during acute phase （all P > 0.05）. Conclusions Except for the upper respiratory tract infection, no significant difference is observed in clinical features and prognosis between GBS patients with and without pain during acute phase. The types and classifications of GBS deserve further validation.

BackgroundSelf-medication behavior often occurs in acutely ill patients, which may lead to a greatly increased risk of adverse drug events. There are few surveys on the accessibility and rationality of in-home self-medication among acute disease patients against a background of implementing multiple policies associated with China's healthcare reform initiated in 2009, and the available surveys mainly focus on central and eastern China.ObjectiveTo investigate the accessibility and rationality of in-home self-medication among acute disease patients in Gansu, offering evidence for standardizing in-home medication, and improving accessibility and rationality of in-home self-medication in this group.MethodsBy use of multistage stratified random sampling, 1 080 households were selected from five cities in Gansu Province from June to December 2018. They were invited to attend a survey guided by the WHO Household Survey to Measure Access to and Use of Medicines for understanding the morbidity in household members in the past two weeks, use and accessibility of medicines for treating acute diseases using a questionnaire developed by our research team. The survey results were statistically analyzed. Spearman correlation analysis was used to analyze the correlation between acute diseases, accessibility and availability of medicines for treating acute diseases and the number of drugs and antibiotics.ResultsOut of the 1 080 households, 1 071 (99.17%) effectively responded to the survey. The prevalence of acute diseases in family members living in these households in the past two weeks was 36.32% (389/1 071) . In this study, we only included the youngest family member with acutely disease in each household, that is, 389 cases in all. Of them, 350 (89.97%) had an acute upper respiratory infection; 355 (91.26%) had the behavior of seeing a doctor or buying drugs; 355 (91.26%) were on medication for treating acute diseases. Among all cases on medication, 279 (78.59%) used combination therapy, 93 (26.20%) had four or more medications simultaneously, and 151 (42.54%) were on antibiotics. Among all antibiotics users, 133 (79.17%) took antibiotics recommended by doctors, and 136 (80.95%) used β- Lactam antibiotics. In terms of medicine accessibility, 334 (85.86%) of acute disease patients were able to reach the nearest medical facility within 15 minutes; 354 (91.00%) and 329 (84.58%) reported that the required drugs were available at the public medical facilities and pharmacy, respectively. Among all cases on medication, 349 (98.31%) had medical insurance, but only 64 (18.34%) were reimbursed; 42 (11.83%) reported that the spending on medicines accounted for over 20% of the total household spending. There were statistically significant differences between patients in urban and rural areas at the avenues of seeing a doctor or buying drugs, types of antibiotics used, 15 minutes proximity to the nearest medical facility, accessibility to drugs at pharmacies, drug reimbursement rates, and spending over 20% of total household expenditure on drugs for acute illnesses (P

As regression testing size and cost increase,test suite reduction becomes more important to promote its efficiency.Du-ring the selection of test suite subset,we are supposed to consider the representativeness and diversity of subset,and apply an effective algorithm to solve it.Aimed at test suite reduction,a submodular function maximization based algorithm,SubTSR,is proposed in this paper.Although the introduced discrete optimization problem is an NP-hard problem,the heuristic greedy search is used in this paper to find the suboptimal solution with approximation guarantee by exploiting the submodularity of the objective function.To validate the effectiveness of the SubTSR algorithm,the SubTSR algorithm is experimented on fifteen datasets with changes of topic count in LDA and distance for similarity measurement,and compared with other test suite reduction algorithms about the average percentage of fault-detection,fault detection loss rate,first faulty test's index and other metrics.The experiment results show that the SubTSR algorithm has significant improvement in fault detection performance compared with other algorithms,and its performance remains relatively stable on different datasets.Under the text representation change due to topic count change,the SubTSR combined with Manhattan distance keeps relatively stable compared with other algorithms.

Curriculum ideological and political is a new topic in the teaching of information security major courses. The wireless communication network security course of Xidian University was taken as an example by the theory of reverse instructional design. By clarifying the concepts and principles of curriculum ideological and political construction, the curriculum ideological and political teaching design was carried out by the means of curriculum front-end design, teaching objective design, determine evaluation evidence, design learning activities, teaching Feedback. Through the demonstration of this case, the reference for how to carry out curriculum ideological and political teaching design in other courses were provided.

Aiming at the problem of the computation of ventilation heat resistance in a roadway during mine fire, to the ventilation roadways with airflow temperature and density variation, a normative computing formula was deduced. It was pointed out that according to generalized ventilation principle, the ventilation resistance during mine fire includes frictional resistance and local resistance, as well as an additional resistance caused by the external ventilation source, namely fire smoke. In the new formula, the computation of ventilation resistance is expressed from two media, namely fluid and roadway, and the conception of roadway geometry air resistance were introduced. Geometry air resistance is the resistance characteristic of roadway itself, and it has nothing to do with fluid. Geometry air resistance includes frictional resistance and local resistance too. Conceptually, the new formula has a clear discrimination to the essence of heat resistance, so the mistakes easily appear during computation and analysis will be avoided. The conclusion that the ventilation resistance of high temperature smoke flow is in direct proportion to fire temperature was drawn. To verify the heat flow resistance effect, an experimental pipeline facility was designed to determine the variation of heat resistance with temperature. The experimental results are identical to the conclusion drawn from theoretical derivation. The additional resistance of exogenous smoke flow was extracted successfully by using the experimental facility. Experimental results show that exogenous resistance is the physical image of combustion process. A practical method for computing the heat resistance with the participation of exogenous gas is provided. [ABSTRACT FROM AUTHOR]