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Between 1958 and 1999, notable lithic localities recorded prehistoric activities in Xiqiao Town of Nanhai District, Foshan City, Guangdong Province, from which double-shouldered and microlith-stone artefacts were uncovered. Currently, the "Xiqiaoshan site" is recognized as a substantial Neolithic quarry and processing location, dating back to 4‒7 ka B P. Subsequently, from 2011 to 2022, we conducted multiple geological environmental surveys and analyses on Xiqiaoshan Mountain. A well-preserved Quaternary stratigraphic profile was discovered north of Fuxian village in the southeast foothills of Xiqiaoshan Mountain. The sedimentological, geochemical, and geochronological results indicate the presence of two primary sedimentary strata in the Fuxian locality. The upper unit comprises the Holocene swamp facies, with a calibrated AMS14C dating range from 5052‒5409 a B P; whereas, the lower unit comprises the late Pleistocene alluvial-diluvial strata, with a calibrated AMS14C dating range from 38420‒40502 a B P, and an optically stimulated luminescence (OSL) dating range of 41.977‒43.796 ka B P. Late Pleistocene strata yielded two sand-gravel layers containing Paleolithic artefacts, which are marked as layers A1 and A2. The predominant artefacts in lower layer A1 include larger scrapers, pointed tools, tongue-shaped edged tools, and small flake tools, such as various scrapers, denticulates, notches, knives, utilized flakes, and cores, including tanged axe-shaped knives. In the upper layer A2, backed or tanged knives appear more frequently. The other small flake tools from this layer (A2) were not significantly different from those in lower layer A1. One bifacially prepared core for producing small elongated flakes is of particular interest for this artefact. Based on the average deposition rate, the computational age of the A1 layer was 46.511‒47.325 ka B P, whereas that of the A2 layer was 41.977‒42.167 ka B P. Although the number of artefacts within the Holocene sediments (>5 ka B P) overlying the late Pleistocene strata is limited, the characteristics of inheritance and development are still evident in the types of artefacts. The discovery presented in this study has completely updated and extended the connotation of Xiqiaoshan National Geopark and "Xiqiaoshan culture,"breaking through the late Pleistocene Paleolithic remains records with exact dating in the Pearl River Delta region for the first time. Therefore, a ground-breaking discovery can accurately trace the footsteps of modern humans in the coastal areas of South China from 40‒50 ka. It also reveals the rich features of lithic industry and the developmental characteristics and evolution of its cultural connotations during this period. The present study shows that during the relatively warm and humid conditions of marine isotope stages 3 (MIS3) interglacial period and the subsequent cold and arid stage of MIS2, human population in the Fuxian locality encountered environmental challenges and adopted new subsistence strategy, which is of great significance for understanding modern human responses and adaptations to global and regional environmental and climate change.

Background and purpose: Rectal cancer occurs on the inner wall of the rectum, and metastasis-associated in colon cancer 1 (MACC1) can promote drug resistance in colon cancer cells. This study aimed to investigate the effect of MACC1 on oxaliplatin resistance in rectal cancer and its mechanism. Methods: Biosignal analysis of MACC1 and TCF7 expressions in rectal cancer tissues and signaling pathways enriched for MACC1 were carried out. The expressions of MACC1 and TCF7 in rectal cancer cells and rectal cancer oxaliplatin-resistant cells were detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR), cell viability was detected by cell counting kit-8 (CCK-8), and cell proliferation was detected by cell colony formation assay. ECAR values, lactate production and glucose consumption were detected by Seahorse Biosciences XF96. Western blot was used to detect the expressions of glycolysis-related proteins. Dual luciferase reporter gene and ChIP were used to validate the regulatory relationship between MACC1 and TCF7. Normality test and homogeneity of variance analysis was performed on the data of each group by GraphPad Prism 8.0. If it conformed to normal distribution, one-way ANOVA or t-test would be used for inter group comparison, otherwise the comparison between groups would be conducted using Wilcoxon rank sum test. Using a two-sided test, P

At the end of 2023, a large-scale rainfall/snowfall and freezing event occurred in northern and central Henan, featuring variable precipitation phases and accompanied by regional thunderstorms, which was relatively rare. This paper analyzed this process by using the data from conventional observations, ERA5 reanalysis, wind profile radar, and dual-polarization radar with a focus on the characteristics of precipitation phases and cause. The results are as follows. (1) At 500 hPa, the horizontal trough turned vertical, and the south branch trough moved eastward, while at 700 hPa, the southwest jet developed. Meanwhile, the ground was affected by the cold air from the east and the west successively, which led to the persistent large-scale freezing rain and snow weather in northern and central Henan. (2) The conditional instability above the cold cushion, the conditional symmetry instability near the frontal zone, and the upward branch of strong frontogenesis circulation provided a favorable condition for the occurrence and development of convective weather, which were the main causes of heavy rain and snow, thunderstorm, and hail. (3) During the process, the freezing rain corresponded to a "thick warm layer (100-200 hPa)-cold layer" stratification, with the ice pellets linking to a "layer of ice crystals - thin warm layer (50-100 hPa) - cold layer" stratification. While the pure snow and sleet corresponded to an entirely cold layer stratification and a shallow warm layer near the ground, respectively. (4) The horizontal wind field products of wind profile radar can qualitatively reflect the changes in the low-level southwest jet stream and the intensity of cold air near the ground. The differences in the vertical velocity products of different precipitation phases are significant, providing a reference for the monitoring and forecasting of short-term phase transitions. (5) The dual-polarization products revealed that the freezing rain and pure snow had the highest correlation coefficients (≥0.99), while the sleet had the lowest (0.85~0.9). The ice pellets showed a significant middle-layer melting, with a maximum differential reflectivity and a minimum correlation coefficient at that level.

Objective To compare the influence of fascia iliaca block (FIB) under ultrasound and intraspinal anesthesia on anesthesia placement position and postoperative analgesia in patients with hip fractures. Methods A total of 83 patients with hip fractures admitted to Wuhu Hospital of Traditional Chinese Medicine from July 2022 to August 2023 were selected and divided into clinical group (41 cases) and control group (42 cases). The clinical group received FIB combined with intraspinal anesthesia, and the control group was given intraspinal anesthesia. Anesthesia effect, perioperative visual analogue scale (VAS) score, fracture recovery Bromage score, dosage of anesthetic drug within 48 h after surgery and occurrence of anesthesia adverse reactions were compared between the two groups. Results The total effective rate of anesthesia in clinical group was 95.12%, which was higher than 78.57% in control group (χ2=4.943, P=0.026). VAS scores in clinical group at the time of changing position and at 6, 12, 24 and 48 h after surgery were lower than those in control group (P＜0.05). The Bromage scores in clinical group at 30 min after analgesia and 12 h to 48 h after surgery were lower than those in control group (P＜0.05). The number of analgesic pump compression and dosage of sufentanil citrate within 48 h in clinical group were significantly lower than those in control group (P＜0.05). There was no significant difference in adverse reactions between the two groups (χ2=0.001, P=0.970). Conclusion FIB has a good analgesia effect during anesthesia placement position and at rest, and it can accelerate the postoperative lower limb muscle strength and hip function recovery, and it is a safe and effective method to relieve pain in patients with hip fractures.

Background Knee osteoarthritis (KOA) is a common clinical condition with a decades-long course. Long-term and personalised health management in community hospitals is the best way to prevent and treat KOA, and non-surgical treatment is an effective way to slow joint degeneration and postpone joint replacement surgery. Objective To understand the population characteristics, clinical staging and treatment modality characteristics of the population attending community hospitals for knee osteoarthritis, in order to provide a basis for optimising the treatment protocol for knee osteoarthritis at the grassroots level. Method All streets in the urban area of Beijing were randomly selected for the study using the whole cluster sampling method, and Hepingli Street in Dongcheng District, Beijing was censored for all patients who attended all community hospitals (7) belonging to the street from January to June 2022, and general information, medical history, personal history, clinical staging, K-L grading and treatment modalities were collected. Results A total of 3 615 KOA patients were included in this study, including 1 327 males (36.71%) and 2 288 females (63.29%), aged (71.8±13.3) years. There were 867 cases (23.98%) in the onset period, 2009 cases (55.57%) in the remission period and 739 cases (20.45%) in the rehabilitation period. Gender and age of patients with different clinical stages were not correlated with clinical stages (P>0.05), while BMI (K=0.235) and KL grading (K=0.406) were correlated with clinical stages (P

In this paper, wheat flour was irradiated at different doses (0, 5, 10, 15, 20 and 25 kGy) to investigate the effects of 60Co-γirradiation on the structural and functional properties of its gluten. The disulfide bond was broken by irradiation, and the content of the free sulfhydryl group increased. The results of Fourier infrared spectroscopy showed that the secondary structure of gluten protein was rearranged with decrease in a-helix content and an increase in β-sheet content. Raman spectroscopy and surface hydrophobicity showed that the microenvironment of aromatic amino acid side chains changed. Irradiation treatment resulted in the tryptophan and tyrosine residues tending more toward the exposed state, and the surface hydrophobicity increased. Meanwhile, irradiation increased the solubility, water and oil holding, and emulsifying properties of gluten proteins, and the maximum value reached at 15 kGy（solubility is 0.46 mg/mL, water holding 3.13 g/g, oil holding 4.33 g/g, emulsification 6.669 m2/g）. In conclusion, the proper dose of gamma-irradiation can change the secondary and tertiary structure of gluten, and improve its functional properties such as solubility, water retention and emulsification, which is conducive to expanding the application space of gluten protein and providing theoretical references for industrial applications.

Objective To investigate the efficacy of antibacterial photodynamic therapy (aPDT) as an adjunct to subgingival scaling and root planning in the treatment of chronic periodontitis. Methods This study followed medical ethics guidelines, and informed consent was obtained from all patients. Sixteen patients were recruited for this randomized split-mouth controlled trial. The control group underwent subgingival scaling and root planning (SRP), while the experimental group received subgingival scaling and root planing plus aPDT treatment using Perowave® with a toluidine blue O solution photosensitizer. The probing pocket depth (PD), recession, plaque index (PLI), bleeding index (BI) and proportion of positive sites of bleeding on probing (BOP) (BOP%) at all sites were examined at baseline (before treatment) and at 1, 3 and 6 months after treatment. Results Follow-up was completed for 13 patients. On the control side, 356 teeth were tested at 2 136 sites. A total of 360 teeth on the test side and 2 160 sites were included in the study. Before treatment, there was no significant difference in the baseline indicators between the two groups. After treatment, both groups showed significant improvement in clinical parameters, including PD, PLI, BI, and BOP%,compared with baseline. At 3 months, the BOP% and PLI in the experimental group were significantly lower than those in the control group (PP

For reduce the carbon emissions of grain transportation, improve ment the efficiency of grain transportation and ensurance the safety of grain transportation, this paper constructed a location-routing optimization model of grain transshipment hub driven by low carbon according to the perspective of quantitative analysis. An improved genetic algorithm was designed to solve the model, which could improve and optimize the layout of China's existing grain transportation network. Finally, some provincial capital cities on the key line of grain logistics were selected for analysis and verification. The results showed that The model and algorithm of hub node sitting-route optimization in hub-spoke multimodal transport network could reduce the total grain transportation cost by 13.87%. Carbon emissions were reduced by 11.70%, and the average transfer saturation of hubs was increased by 9.66%. This method was suitable for the actual grain transportation process, and can realize the low-carbon and efficient transportation of grain, which could provide reference for the location and path planning of Chinese grain transport hub under low-carbon drive.

Phosphoric acid is commonly used to react with carbonates to generate carbon dioxide for determining the carbon and oxygen isotopes of carbonates by using online reaction device, for example, GasBench coupled to an isotope ratio mass spectrometer (IRMS). During the measurement, oxygen isotope fractionation will arise due to various factors, which can result differences between the measured oxygen isotope values and the actual ones. In this study, a series of carbonate standard materials (international standard materials IAEA-603, NBS18, and national standard materials GBW04416 and GBW04405) and modern marine planktonic foraminiferal samples were determined to explore the contribution of acid fractionation on the oxygen isotope values under different conditions. The effects of acid fractionation on the oxygen isotope values for each standard material, and the underlying mechanism were investigated and discussed. The results showed that: 1) The acid fractionation effect is mainly caused by the exchange of oxygen isotopes between the sample CO2 gas and the evaporated gas phase water in the headspace bottle (at high temperatures) or by the liquid water in the acid (at low temperatures); 2) The acid fractionation coefficients of oxygen isotope in carbonate reference materials with different characteristics show significant differences and are related to their oxygen isotope compositions; 3) The degree of deviation of oxygen isotopes is related to the factors such as reaction temperature, sample quantity, water content of phosphoric acid, and the difference between the oxygen isotope composition of liquid and gaseous water in the acid and the oxygen isotope composition of the samples; 4) The acid fractionation effect on oxygen isotopes is significantly correlated with signal intensity. It is recommended to effectively correct the oxygen isotope fractionation of acid by accurately weighing reference materials and samples, following the principle of peak intensity matching and adopting linear correction method for determination of oxygen isotopes in carbonates. Besides, a lower reaction temperature (25 ℃) generates slighter degree of oxygen isotope fractionation. This study provides a useful reference for the accurate determination of carbon and oxygen isotope composition in carbonates, and is of great significance for improving analysis accuracy.

Objective To detect the expression changes of interleukin-10 （IL-10） and transforming growth factor-β1 （TGF-β1） during the development of deep vein thrombosis in mice, and to explore the application value of them in thrombus age estimation. Methods The mice in the experimental group were subjected to ligation of inferior vena cava. The mice were sacrificed by excessive anesthesia at 1 d, 3 d, 5 d, 7 d, 10 d, 14 d and 21 d after ligation, respectively. The inferior vena cava segment with thrombosis was extracted below the ligation point. The mice in the control group were not ligated, and the inferior vena cava segment at the same position as the experimental group was extracted. The expression changes of IL-10 and TGF-β1 were detected by immunohistochemistry （IHC）, Western blotting and real-time qPCR. Results IHC results revealed that IL-10 was mainly expressed in monocytes in thrombosis and TGF-β1 was mainly expressed in monocytes and fibroblast-like cells in thrombosis. Western blotting and real-time qPCR showed that the relative expression levels of IL-10 and TGF-β1 in each experimental group were higher than those in the control group. The mRNA and protein levels of IL-10 reached the peak at 7 d and 10 d after ligation, respectively. The mRNA expression level at 7 d after ligation was 4.72±0.15 times that of the control group, and the protein expression level at 10 d after ligation was 7.15±0.28 times that of the control group. The mRNA and protein levels of TGF-β1 reached the peak at 10 d and 14 d after ligation, respectively. The mRNA expression level at 10 d after ligation was 2.58±0.14 times that of the control group, and the protein expression level at 14 d after ligation was 4.34±0.19 times that of the control group. Conclusion The expressions of IL-10 and TGF-β1 during the evolution of deep vein thrombosis present time-dependent sequential changes, and the expression levels of IL-10 and TGF-β1 can provide a reference basis for thrombus age estimation.

Abstract [Objective] This study aims to investigate the impact of Streptomyces pactum Act12 broth on growth and physiological characteristics of Medicago sativa seedlings under petroleum stress. [Methods] The effects of different concentrations (0, 1%, 10%, and 100%) of Act12 broth under a petroleum stress level of 3% (W/W ) were examined by determining seedling growth, root morphology, photosynthetic characteristics, osmoregulatory substance content, and antioxidant capacity in M . sativa. [Results] The 3% petroleum significantly hindered photosynthesis and biomass accumulation of M . sativa seedlings, compared to the control group (CK). Moreover, it resulted in elevation in malondialdehyde level, decrease in soluble sugar and soluble protein content, as well as alteration in the activities of superoxide dismutase (SOD) and peroxidase (POD). Compared to the absence of Act12 broth, solutions with low and medium concentrations (1% and 10%) effectively mitigated the toxic effects of petroleum, with 10% Act12 broth exhibiting the most significant effect. The seedlings treated with Act12 broth exhibited significant enhancements in plant height, above-ground dry mass, underground dry mass, stem tolerance index, root tolerance index, total root length, root surface area, root volume, and number of root tips. Additionally, the level of MDA was decreased by 42.49% and 56.45%, soluble sugar was increased by 79.25% and 89.83%, while soluble protein was increased by 167.63% and 256.15% in the above-ground and underground parts, respectively. Moreover, SOD and POD activity were increased by 35.81% and 57.33%, respectively. [Conclusion] The fermented liquid with low/medium concentration effectively modulates antioxidant enzyme activity and osmotic regulation ability of seedlings, resulting in reduced MDA content, enhanced photosynthesis ability, increased biomass, and eventually alleviates the inhibition effects of petroleum stress on seedling growth.

In recent years, both morbidity and mortality of chronic kidney disease （CKD） have been rising rapidly and cardiovascular disease （CVD） is one of major causes. Traditional cardiovascular risk factors cannot fully explain this phenomenon. Therefore such CKD-specific risk factors as uremic toxins （UTs） have emerged as crucial players. This review focused upon typical protein-binding toxin of indoxyl sulfate （IS）. It described the mechanisms of effects in the occurrence and development of CKD and depicted an association with IS and CKD-related CVD by four aspects of atherosclerosis, arteriosclerosis, congestive heart failure and arrhythmias. Also effective therapeutic measures of reducing serum level of IS were introduced, including restriction of protein intake, modulation of intestinal flora, using oral intestinal adsorbents and innovative dialysis approaches of enhancing IS clearance. And albumin-binding competitors appear to be an effective removal of protein-binding UTs. In the future, more modes of IS clearance shall be discovered and verified whether or not they can slow the progression of CKD and lower the incidence of CKD-related cardiovascular disease in CKD.

Electrochemical interfaces are the core of various important fields, such as energy conversion and storage, biochemistry, sensors, and corrosion. The investigations of the structure-performance relationship of electrochemical solid-liquid interfaces have become a hot topic yet extremely challenging due to the fact that the interfaces are ultrathin, highly dynamic and extremely complex. Mass spectrometric techniques coupled with electrochemistry are powerful and have been widely applied in investigations of mechanisms of electrochemical reactions. However, traditional mass spectrometry (MS) is difficult to characterize the electrode-electrolyte interfaces in an in situ manner due to inherent limitations existing in their ionization processes. In recent years, the state-of-the-art in situ liquid time-of-flight secondary ion MS (ToF-SIMS) based on high-vacuum compatible microfluidic devices has been developed to tackle with this challenge. This review mainly reviewed the principle, characteristics and rapid development of in situ liquid ToF-SIMS in real-time and in situ investigations of electrochemical solid-liquid interfaces during the past decade. In situ liquid ToF-SIMS possesses shallow information depth (nm), high temporal resolution (μs) and high detection sensitivity (10-6-10-9). Besides, it ionizes the electrochemical interfaces in a truly in situ manner and provides direct molecular evidences of chemical evolution of both electrode/electrocatalyst surfaces and reactants/intermediates/products in electrolytes at the interfaces simultaneously. Being attributed to its uniqueness, in situ liquid ToF-SIMS has become a powerful and versatile molecular "eye" in in situ and real-time tracking dynamic electrochemical solid-liquid interfaces, such as capturing electrochemical reaction intermediates, identification of electrocatalytic active sites, probing fine structures of electrochemical double layers, and unraveling the formation chemistry of solid-electrolyte interphases in batteries. Further innovations of microfluidic electrochemical devices and ToF-SIMS instruments are desired to promote the enhanced performance and wider applications of in situ liquid ToF-SIMS in the electrochemical field, and in situ liquid ToF-SIMS will make significant contributions to the understanding of the structure-performance relationship of interfaces in complex electrochemical assays and guide the engineering of better electrochemical interfaces in important fields, such as electrocatalysis and batteries.

BackgroundAnimal experimental studies have shown that arsenic exposure contributes to hepatic lipid accumulation, but epidemiological findings are inconsistent. Moreover, the role of arsenic metabolism is still unclear. ObjectiveTo evaluate the potential causal association between arsenic metabolism and non-alcoholic fatty liver disease (NAFLD). MethodsA total of 1020 participants from the Dongfeng-Tongji cohort with urinary arsenic metabolites and genotype data were included in the present study (NAFLD group, n=529; non- NAFLD group, n=491). Epidemiological information was obtained by questionnaire survey, liver ultrasound was obtained by physical examination, arsenic metabolites in urine were measured by high-performance liquid chromatography-inductively coupled plasma mass spectrometry, and DNA from leukocytes was extracted for genome-wide genotype. NAFLD was diagnosed if the following two criteria were met: (1) positive fatty liver according to abdominal ultrasonography; (2) excluding participants reporting history of excessive alcohol consumption (≥30 g·d−1 for men; ≥20 g·d−1 for women) and/or fatty liver with other known causes. Genetic risk score (GRS) and weighted genetic risk score (w-GRS) were constructed using single nucleotide polymorphisms (SNPs) related to arsenic metabolism reported in previous studies to predict the estimated arsenic metabolism. Logistic regression models were used to analyze the association between arsenic metabolism and NAFLD; linear regression models were used to analyze the association between GRS/w-GRS and arsenic metabolism, and Mendelian randomization analysis was performed using GRS method, inverse variance weighting, Egger regression, and weighted median. ResultsThe mean age of the 1020 participants was (68.14±7.45) years, of which 64% were female, and 529 (51.9%) were NAFLD cases. The median (P25, P75) level of total arsenic in urine was 18.34 (11.93, 27.14) μg·L−1 with a geometric mean and standard deviation of (15.86±1.81) μg·L−1. The proportions of inorganic arsenic (iAs%), monomethylarsenic (MMA%), and dimethylarsenic (DMA%) in the total arsenic were 13.90%±9.90%, 9.49%±4.97%, and 76.60%±11.00%, respectively. After adjustment for potential confounders, the ORs (95%CIs) for NAFLD risk by per standard deviation increase in iAs% and MMA% were 1.21 (1.06, 1.38) and 0.62 (0.51, 0.74) respectively. Each unit increase in GRS constructed from 77 SNPs was associated with a 0.16% increase in MMA% and a 0.19% decrease in DMA%, and each unit increase in w-GRS was associated with a 0.17% increase in MMA% and a 0.14% decrease in DMA%. After further exclusion of SNPs with linkage disequilibrium (r2>0.3) and pleiotropic effect, a total of 25 SNPs were included in the Mendelian randomization analysis. The GRS method showed that the OR (95%CI) for NAFLD risk by per unit increase in MMA% expectation was 0.95 (0.90, 0.99), and the inverse variance weighting method also showed a significant association between MMA% and NAFLD, with OR (95%CI) of 0.91 (0.84, 0.99). ConclusionThere is a negative causal association between MMA% and NAFLD.

The intestinal flora of the human body is closely related to health. Gut microbiota dysbiosis will lead to intestinal dysfunction and, consequently, a variety of intestinal diseases. In this study, subjects with different diseases were requested to take one of three microecological agents, stachyose, composite probiotics (CPb) and synbiotic MF-13. An Ion Torrent PGM™ sequencing platform was used to analyze the structure of intestinal microflora and the contents of cholesterol and bile acid in the feces of the subjects were measured. Our aim was to investigate the regulatory effect of intervention with microecological agents on the intestinal microflora structure and lipid metabolism. The results showed that 1 067 operational taxonomic units (OUT) were obtained from the fecal microbial samples from all subjects. The dominant bacteria were Firmicutes and Bacteroidetes, altogether accounting for 91.65%, and Bacteroidetes accounting for about 70.10% of the total number of sequences. Bacteroides and Prevotella were the dominant genera, accounting for 33.1% and 33.8% of the total sequences, respectively. At the phylum level, stachyose promoted the proliferation of Bacteroidetes, but inhibited the proliferation of Firmicutes. CPb had no significant effect on the abundance of each phylum, while MF-13 promoted the proliferation of Proteobacteria and Actinobacteria. Stachyose significantly decreased the abundance of Sutterella in subjects with constipation and insomnia, CPb significantly decreased the abundance of Sutterella in subjects with diarrhea, and MF-13 increased the abundance of Parabacteroides. The analysis of intestinal microflora diversity showed that Chao1 index significantly increased during the early period of MF-13 intervention, while there were no significant changes in other diversity indexes. Cluster analysis and non-metric multi-dimensional scaling (NMDS) analysis showed that microecological preparation intervention changed the intestinal microbiota structure in most of the samples, and the microflora structure of all populations showed an overlapping tendency. The intestinal microflora species that significantly differed between individuals were analyzed using Metastat statistics, and it was found that there was no significant change in the abundance of OTUs before and after intervention with each microecological agent, while there was a significant difference between individual subjects. MF-13 significantly promoted the fecal excretion of cholesterol and bile acids (P < 0.05). In conclusion, stachyose has an obvious influence on the intestinal microflora structure of volunteers, while CPb and MF-13 do not. However, MF-13 can increase the intestinal excretion of cholesterol and bile acid, which is beneficial to the metabolism of intestinal cholesterol, but the durability of this effect is poor.

Objective To investigate the effect of quality control circle (QCC)activities in improving the standardized implementation rate of peripheral venous thrombolysis for lower-limb deep venous thrombosis (DVT). Methods A QCC group was set up. Factors causing failed implementation rate of DVT were analyzed, and countermeasures were carried out for continuous quality improvement. Results The standardized implementation rate of peripheral venous thrombolysis for lower-limb DVT increased form 33. 33% before QCC activities to 91. 25% after QCC activities, with a significant difference (P＜0. 05). Conclusion The implementation of QCC activities for continuous quality improvement of standardized procedure of peripheral venous thrombolysis may help to improve the effect of thrombolytic therapy. (目的 探讨品管圈在提高下肢深静脉血栓形成(DVT)患者外周静脉溶栓执行规范率中的效果。方法 成立品管圈小组, 进行品管圈知识培训, 选定活动主题, 进行现状调查, 分析下肢DVT患者外周静脉溶栓执行不合格原因, 制定对策并实施质量持续改进。结果 下肢DVT患者外周静脉溶栓执行规范率由品管圈活动前的33. 33%提高至开展品管圈活动后的91. 25%, 差异有统计学意义(P＜0. 05)。结论 开展品管圈活动, 对下肢DVT患者外周静脉溶栓执行规范率进行持续改进, 可以有效提高溶栓效果。)

Food concerns national livelihood and food security is vital for national security. In the context of “dual circulation” (i.e., domestic and international economic circulation) in China, clarifying the basic situation and challenges of food security and exploring effective strategies for food development are crucial for ensuring stable national development. Using national macro statistics, we first analyzed the basic situation of food security in China and the challenges it faces in the context of “dual circulation”. Subsequently, we made a macro study on national food security and proposed the goals, strategic paths, major projects, and feasible countermeasures for ensuring national food security. Our study indicates that there exists a large gap between food supply and demand, a high degree of external dependence, and a large amount of imports of feed protein in China, as well as challenges including the difficulty in substituting feed protein domestically, rigidness of environmental restrictions on soil and water resources, low incentives for farmers to grow grains, and insufficient risk-resistant capabilities of the food security system. Moreover, we proposed a series of major projects, such as demonstration for upgrading grain production capacity, new protein resource substitution, green and lowcarbon planting and breeding circulation, development and utilization of international grain resources, and research and development demonstration of future foods. Several development strategies were further suggested, including the establishment of a food security guarantee system, moderate expansion of cultivated land areas, sustained increase in oil-bearing plant production, steady resumption of a multiple cropping system in South China, and sustained advancement of a rotational cropping system in North China.

To study the corrosion behavior of three commonly used steels in associated gas pipelines in the three-gas coexistence system of H2S-CO2-O2 can provide guidance for the corrosion prevention and control of associated gas pipelines in Tahe oilfield.Based on the typical corrosion working conditions in Tahe oilfield and taking 20 steel，L245NS steel and 3Cr steel as the research objects，the corrosion rates and corrosion products of the three steels under typical working conditions in H2S - CO2- O2 coexistence system were studied through high -temperature and high-pressure reactor experiment.Results showed that the corrosion rate of 20＃ steel was the highest，followed by L245NS steel，and the corrosion rate of 3Cr steel was the lowest.The corrosion products of the three pipes were mainly Fe，FeS，FeCO3 and Fe2O3.The corrosion resistance behaviors of four typical internal anti-corrosion coatings in Tahe oilfield were studied through an adhesion test and the weight gain method that involved the measuring of the weight gain before and after corrosion，and the results indicated that coating 2 possessed the optimal corrosion resistance and adhesion.Considering the cost performance，“L245NS+coating 2”was finally selected as the anti-corrosion measure for the associated gas pipelines in Tahe Oilfield.

A 40-year-old male patient presented with an unexplained pericardial effusion and was treated with antituberculosis therapy. This patient showed a transient improvement, but then progressively worsened to develop constrictive pericarditis, multiple plasma chamber effusions, and venous thrombosis. The patient was transferred to Zhongshan Hospital, Fudan University. Through a pleural histopathological biopsy, this patient was diagnosed with pleural mesothelioma and secondary malignant tumor of the pericardium. Later, clinical the manifestations of patient progressed rapidly, resulting in the death of the patient. Mesothelioma is a very rare group of malignant tumors originating from the pleura and other tissues. Patients are mostly advanced at the time of initial diagnosis, with limited treatments and short median survival. It is important to strengthen the understanding of mesothelioma, pay attention to all medical and technical examinations, especially dynamic follow-up of changes in the disease for early diagnosis of this disease.

In recent years,with the development of unmanned driving,intelligent UAV and mobile Internet,the demand for lightweight neural network from low-power,low-cost mobile and embedded platforms is increasingly urgent.Based on the idea of deformable convolution and depthwise separable convolution,this paper presents a low-cost deformable convolution,which has the advantages of high-efficiency feature extraction ability of deformable convolution and low computational complexity of depthwise separable convolution.In addition,on the basis of applying low-cost deformable convolution and combining with the method of model structure compression,4 lightweight methods of MobileNet network are designed.Experiments on Caltech256,CIFAR100 and CIFAR10 datasets demonstrate that low-cost deformable convolution can effectively improve the classification accuracy of lightweight networks without significant increase in computational effort.Besides,the accuracy of the MobileNet network can be improved by 0.4%~1% by combining the 4 MobileNet re-lightening methods in this paper,while the network computing load can be reduced by 5% ~ 15%,which significantly improves the performance of the lightweight network and better meets the practical needs of low power consumption and low computing power.It has very important practical significance for the advancement of intelligence in the field of mobile and embedded platforms.

The drying is an important part of the processing of Ziziphi Spinosae Semen (ZSS) in the producing area and has an important effect on the quality of ZSS. In this study, an integrated 1H nuclear magnetic resonance and gas chromatography-mass spectrometry method was developed to reveal the effects of vacuum drying (VD), freeze-drying (FD), and hot air drying (HAD) method on the chemical composition and antioxidant activity of ZSS. Then the effects of different drying methods on the quality of ZSS were investigated. The results showed that the VD produced high contents of 6 fatty acids (palmitic acid, linoleic acid, oleinic acid, stearic acid, squalene, and γ-tocopherol), 7 amino acids (leucine, isoleucine, valine, alanine, γ-aminobutyric acid, glutamine, and threonine), and 2 carbohydrates (α-glucose and β-glucose), but exhibited weak DPPH radical scavenging activity, ABTS cation radical scavenging activity and FRAP antioxidant activity (FD>VD>HAD). However, FD gave an improved secondary metabolite profile retention, such as jujuboside A, betulinic acid, magnoflorine, and 6ʹʹʹ-feruloylspinosin, thereby resulting in a superior DPPH radical scavenging activity (IC50: 2.82±0.15 mg/mL), ABTS cation radical scavenging activity (IC50: 0.86±0.02 mg/mL) and FRAP antioxidant activity (58.91±2.87 mg VC/g). Thus, FD was a suitable drying method to maximize the product quality retention of ZSS. This study can provide a scientific reference for the establishment of reasonable processing technical specifications of ZSS and provide an experimental basis for improving the quality of ZSS.

Non-Line-of-Sight (NLOS) Underwater Wireless Optical Communication (UWOC) is mainly realized through the air-seawater interface reflection or the scattering of light by particles in seawater. It can effectively solve the link alignment issues of Line-of-Sight (LOS) underwater wireless optical communication. This paper summarizes the research progress of NLOS UWOC technology in the aspects of channel model, simulation and experiment. At present, scholars mainly explore the effects of water quality, wave, turbulence, modulation technology, receiving and sending terminal configuration on the performance of NLOS UWOC link. Few scholars have studied the effects of complex hydrodynamic and water quality factors, non-linearity of light source, non-linearity, sensitivity and noise of detector on the performance of NLOS UWOC and effective solutions. Therefore, it is necessary to carry out more in-depth channel model, simulation and experimental research in the future, so as to promote the development of NLOS UWOC technology.

【Objective】In order to study the genetic mechanism of sweet corn pericarp thickness and select high-quality sweet corn varieties, the major genes and polygenes genetic analysis and QTL mapping of sweet corn pericarp thickness were carried out.【Method】The sweet corn inbred lines T15 and T77 with large differences in pericarp thickness were selected to prepare hybrid combination (T77×T1). The F2 population of the combination was used as the experimental material, the main genes and polygenes hybrid genetic method was used to analyze relevant parameters of the genetic model; Combined with the pericarp thickness and SSR genetic linkage map of each individual plant in F2 population, QTL mapping of pericarp thickness in sweet corn was carried out by using composite interval mapping method.【Result】It was found that A-1 was the optimal model for sweet corn pericarp thickness, that is, an additive and partially dominant genetic model controlled by a pair of major genes, and the heritability of major genes was 69.10%. There were three QTLs identified on chromosomes 5 and 8 respectively, which were related to pericarp thickness. Two QTLs were detected in region bin 5.04 of chromosome 5, which were located in the marker interval bnlg150-bnlg653 and bnlg653-bnlg1208 respectively, and the additive effect values were -2.39 and -3.01 respectively. The QTL located on chromosome 8 was in bin8.03-bin8.04, the marker interval was umc1741-bnlg2046, the additive effect value was -3.06, and the contribution rate to phenotype was 22.02%.【Conclusion】The pericarp thickness of sweet corn is dominated by the effect of major genes. In breeding practice, genetic improvement and selection can be carried out in the early generation. The QTLs detected in this experiment can be used for molecular marker assisted selection and quality breeding.

Objective: To purify and comprehensive identify αS1-casein from bovine caseins and prepare rabbit polyclonal antibody against αS1-casein. Method: DEAE Sepharose Fast Flow anion exchange chromatography was used to separate and purify αS1-casein. The physicochemical property (isoelectric point and protein content), immunological technique and mass spectrometry were used to comprehensively identify αS1-casein. Then the αS1-casein was obtained by dialysis and lyophilization, polyclonal antibody was prepared by immunizing New Zealand white rabbit with the purified αS1-casein, and the specificity of polyclonal antibody was analyzed. Result: Among the four kinds of caseins, αS1-casein had the latest peak time, the largest peak area in anion exchange chromatography and the highest position in the electrophoretic diagram. Finally, the purity of αS1-casein was 94.26%, and the yield was 27.19%. The titers of sera from two rabbits inoculated with purified αS1-casein for five times reached 1280000 and 320000, respectively. In addition to the slight cross reaction with soybean protein (

Objective To summarize the clinical, imaging and genetic characteristics of spinocerebellar ataxia 2 (SCA2) families presenting as Parkinsonism. Methods and Results Two families with autosomal dominant SCA2 with Parkinson's syndrome diagnosed by genetic test in Peking University First Hospital from May 2019 to December 2020 were included. The probands in 2 families manifested as lead⁃pipe like rigidity and cerebellum ataxia. Electronystagmography (ENG) in proband of family 1 showed gaze nystagmus, understable saccade, decreased smooth tracking ability and disappeared optokinetic nystagmus, proband of family 2 showed slow saccade, decreased smooth tracking ability and decreased optokinetic nystagmus. Head MRI in both probands of 2 families showed slightly enlarged third ventricle, while the proband of family 2 showed atrophy in brain stem and cerebellar. Whole exome sequencing (WES) in 2 probands showed no gene mutations, Sanger sequencing showed dynamic mutation of ATXN2 gene and the copy number of cytosine⁃adenine⁃guanine (CAG) with 37 repeats. Two probands were finally diagnosed as SCA2, and two pedigrees were diagnosed as SCA2 pedigrees. Conclusions SCA2 can present as Parkinsonism, which is easily to be misdiagnosed as Parkinson's disease due to the effective treatment of levodopa. ENG is helpful in detecting subclinical cerebellar lesions. For Parkinsonism patients with family history, especially when cerebellar lesions are involved, ATXN2 gene testing is recommended.

To make an effective correlation analysis on the factors influencing the corrosion and perforation of high sulfur associated gas pipeline in Tahe Oilfield, the pipeline flow parameters were calculated using multiphase flow transient model, and a method combining Pearson correlation coefficient with Apriori association rule mining algorithm was proposed to determine the associativity rules that affecting corrosion perforation. Results showed that the multiphase flow transient model revealed the variation laws of pipeline temperature, pressure, flow rate, and liquid holdup along the pipeline. Meanwhile, the degrees of influences of medium parameters and flow parameters on corrosion were as follow: liquid holdup (0.732) > temperature (0.696) > pressure (0.677) =CO2 partial pressure (0.677) = H2S partial pressure (0.677) > gas flow rate (0.618) = gas wall shear force (0.618) > pipe inclination (0.577). The strong correlation rules between the corrosion rate and H2S partial pressure, temperature, liquid holdup, flow rate and pipeline inclination were determined. Besides, the correctness of the association rules was further verified by the high temperature and high pressure dynamic reactor experiment.

Background Doctor-patient communication barrier is one of the major causes leading to medical disputes. Still, there are limited studies and rare instruments with good reliability and validity regarding doctors' ability to communicate with patients in China. Objective To construct the Five Habits Coding Scale (5HCS) and verify its reliability and validity. Methods The first draft of the Five Habits Coding Scale (5HCS) was formulated based on the Chinese version of the Four Habits Coding Scheme (4HCS) developed using Brislin's translation model in March 2014. Then from April to June 2014, the items of the first draft of 5HCS were revised in accordance with the expert consensuses obtained from two rounds of Delphi consultations, and after that, the final version of the 5HCS was developed, and utilized to evaluate 127 residents' abilities to communicate with patients in March 2018 for testing its internal consistency, inter-rater reliability, content validity and criterion-related validity. Results The final version of 5HCS consists of 21 items fell under 5 dimensions, namely "Show respect and kindness, harmonize doctor-patient relationship" "Provide information, guide patients' views" "Demonstrate empathy, build up trust" "Risk disclosure, informed consent", and "Provide diagnostic information, shared-decision making". The Cronbach's α of the scale was 0.716. The dimension-total correlation coefficients (Pearson correlation coefficients) ranged from 0.524 to 0.692, and the content validity index of each item (I-CVI) ≥0.81. The inter-rater reliability was calculated by intraclass correlation (ICC) (Pearson coefficient=0.912, ICC=0.912, P

With the extension of oilfield production life and the complication of its service environmental conditions, the applicability of the inner coating would be being challenged. In this work, the service condition of epoxy black ceramic coating in Tahe oilfield was simulated by using high-temperature autoclave to study the corrosion resistance of coatings in gas, oil and water phases, and the electrochemical characteristics of the coating in 6 kinds of simulated working conditions such as H2S dominated, H2S / CO2 coexistence and CO2 dominated were analyzed by the electrochemical AC impedance technique (EIS). Results showed that the epoxy black ceramic coating possessed good corrosion resistance characteristics under working conditions, and the AC impedance value was higher than 107 Ω·cm2. From the filed application, the coating had good adhesion to the substrate and good cathodic stripping resistance. Moreover, the failure mechanism of coatings was discussed preliminarily, and their service life under field conditions was preliminarily predicted. Coating defects became a fast channel for the diffusion of water and various ions, electrochemical corrosion occurred at the interface between the coating and the substrate, resulting in the increase of local pressure at the interface and the blistering and cracking of the coating. Furthermore, the life of epoxy black ceramic coating predicted by quadratic polynomial of fitting curve was 517 d.

Recovering dynamic magnetic resonance imaging (MRI) from highly undersampled raw data is of great significance, and is an important approach for achieving both high temporal and spatial resolution in dynamic contrast enhanced imaging. In this study, a method for 3D dynamic MRI with high spatiotemporal resolution and motion insensitivity was developed, which combines golden angle variable density spiral trajectory, parallel imaging and homotopic l0 minimization-based compressed sensing. Golden angle variable density spiral trajectory, which has the advantages of high data acquisition efficiency and motion insensitivity, was used to acquire k-space data. In the reconstruction algorithm, multicoil sparsity constrain was applied in the temporal total variation domain and l0 minimization, instead of traditional l1 minimization, was adopted, which could further increase the undersampling rate. Simulations and in vivo experiments demonstrated that high spatial resolution and temporal resolution can be achieved by the proposed method while maintaining the image quality. This study also suggested the advantages of homotopic l0 norm-based 3D dynamic MRI reconstruction and its clinical potential.

Rough set theory is a mathematical tool for dealing with uncertain information.The core notions of rough set theory is approximation operators of approximation spaces.Pawlak approximation operators are established by using equivalence relations on the universe.They are extended to generalized rough approximation operators based on arbitrary binary relations.The topolo-gical structures of approximation operators are important topics in rough set theory.This paper is devoted to the study of topological properties of generalized rough approximation operators induced by arbitrary binary relations.Four types of topologies induced by generalized approximation operators based on granules and subsystems are presented and the relationships among these four types of topologies are discussed.The bases of the topologies induced by generalized approximation operators based on granules are presented by the right-neighborhood systems for objects,and the normality and regularity for related topologies are investigated.By analyzing the properties of the generalized upper approximation operators based on the subsystem,it is proved that the topologies induced by the subsystem-based generalized upper approximation operators can be transformed into the topologies induced by the generalized lower approximation operators based on the objects.

Objective To explore the influence of family environment on depression in middle school students, and explore the role of coping styles in this process. Methods A multi-level sampling method was conduct in Qingpu District. A total of 1 902 junior and senior school students from four middle schools were investigated. The questionnaires included self-designed questionnaire which was used for collecting the students' information of gender, age, family environment and so on, coping style questionnaire for middle school students which was used for evaluating the scores of coping factors, Patient Health Questionnaire (PHQ-9) which was used for evaluating the scores of depression. The t-Test, Mann-Whitney Test, Pearson correlation analysis and Spearman rank correlation analysis were used for difference analysis or correlation analysis, and the SPSS Process was used for Mediation analysis. Results The PHQ-9 scores of junior high school students in the adverse family environment (divorced/single-parent family, unharmonious family atmosphere, and non-wealthy family) were significantly higher than those in favorable family environment (non-divorced/single-parent family, harmonious family atmosphere, and wealthy family). Students in the adverse family environment scored higher in "problem-focused coping" and lower in "emotion-focused coping", while students in adverse family environment scored the opposite. The results of mediation analysis showed that "emotion-focused coping" played a partial mediating role in the relationship between depression and family structure (β = 0.212, 95%CI: 0.029-0.421) or family atmosphere (β = 0.304, 95%CI: 0.169-0.461) or family economic status (β = 0.261, 95%CI: 0.058-0.491) in the middle school students, and the mediation effect accounted for 9.83%, 15.13% and 13.85% of the total effect respectively. "Problem-focused coping" also played a partial mediating role in the relationship between depression and family structure (β = 0.316, 95%CI: 0.139-0.521) or family atmosphere (β = 0.455, 95%CI: 0.311-0.626) or family economic status (β = 0.505, 95%CI: 0.306-0.730) in the middle school students, and the mediation effect accounted for 14.68%, 22.72% and 26.75% of the total effect respectively. Conclusion The adverse family environment is a risk factor for depression in middle school students, and coping styles play a partial mediating role in this process. [ABSTRACT FROM AUTHOR]

Objective To understand intake frequency of sugar-sweetened beverages (SSBs) and the consumption habit among primary and secondary students. To explore the relationship of SSBs cognition and behavior, and to provide a basis for reducing students' intake of SSBs. Methods A multi-stage sampling process was employed to select subjects from primary and middle school in Shenzhen. Network questionnaire survey was conducted to collecting information in September and October, 2021. Spearman rank correlations was used to analyze relationships of various types of SSBs consumption frequency. Multivariable linear regression model was used to examine the relationship between SSBs cognition score and consumption frequency score. Hierarchical analysis to explore the interactions. Results A total of 16 840 primary and secondary students aged 6 to 18 years old were included. The prevalence of SSBs consumption at least 3 time/week was 58.9%, the grades 1-3, 4-6 and middle school students were 52.3%, 60.3% and 67.6%. Parents (73.3%) were the main buyers of SSBs, convenience stores (73.7%) were the main places and delicious (77.2%) was the major cause of choices. There was a positive correlation between the intake frequency of different types of SSBs (P < 0.001). The results of multivariate linear regression showed that the higher the cognition was, the lower the intake frequency of SSBs was (β = 0.179, 95%CI: 0.155-0.204). There was a multiplicative interaction between the cognitive score of SSBs and the educational level of parents (P < 0.00l). Conclusion The intake frequency of SSBs was high among primary and middle school students in Shenzhen, and the cognitive level of SSBs was related to the intake frequency and the educational level of parents. [ABSTRACT FROM AUTHOR]

In order to clarify the stress situation of buried elbow in a certain sulfur oil and gas field, by analyzing the stress factors of a buried elbow in this oil field, the stress parameters affecting the elbow are simulated and calculated.Results showed that the stress at the elbow increased with the increase of the operating temperature, and it presented approximately linear relationship.Under operating conditions with higher operating temperature, the stress at the elbow decreased as the operating pressure increased.Under operating conditions with lower operating temperature, the stress at the elbow increased with increasing operating pressure.Moreover, the stress at the elbow increased first and then decreased as the angle of the elbow increased.According to the change rule of the influence of various factors on the stress of the elbow, the influence factors of the comprehensive parameters of stress evaluation at the elbow were determined, and the stress risk of the elbow in the field engineering was quickly investigated.

Aiming at the problems of the unreasonable structure and the low efficiency of the traditional statistical partition and publishing of location big data, a deep learning-based statistical partition structure prediction method and a differential publishing method were proposed to enhance the efficacy of the partition algorithm and improve the availability of the published location big data.Firstly, the two-dimensional space was intelligently partitioned and merged from the bottom to the top to construct a reasonable partition structure.Subsequently, the partition structure matrices were organized as a three-dimensional spatio-temporal sequence, and the spatio-temporal characteristics were extracted via the deep learning model in a bid to realize the prediction of the partition structure.Finally, the differential privacy budget allocation and Laplace noise addition were implemented on the prediction partition structure to realize the privacy protection of the statistical partition and publishing of location big data.Experimental comparison of the real location big data sets proves the advantages of the proposed method in improving the querying accuracy of the published location big data and the execution efficiency of the publishing algorithm.

1,3,5-tris（3,3,3-trifluoropyl）-1,3,5-trimethylcyclotrisiloxane （D3F） and hexamethylcyclotrisiloxane were used as raw materials to synthesize fluorosilicone copolymer with high molecular weight. The effects of reaction time and reaction temperature on molecular weight of the products and monomer ratio on chain segment content of the copolymers were studied. The structure of the copolymer was characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy, and its molecular weight was determined by Ubbelohde viscometer. The results showed that the proportion of chain segment content in fluorosilicone rubber was closer to that of feed when D3F amount was high. With increase of reaction temperature and time, molecular weight of the fluorosilicone copolymer first increased and then decreased. Molecular weight of fluorosilicone copolymer could be effectively increased by stopping heating at an approp-riate node in the reaction process. When the reaction temperature was 90 ℃, reaction time was 10 min and mole fraction of D3F was 80%, molecular weight of fluorosilicone copolymer reached the maximum, and the viscosity average molecular weight was 8.2×105.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely applied in the treatment of inflammation, fever and for pain relief based on its efficacy in anti-inflammatory, anti-rheumatic, analgesic, antipyretic, and anticoagulation. Moreover, the relationship between NSAIDs and immune cells is quite important since. NSAIDs can negatively regulate B cell proliferation via inhibiting prostaglandin (PG), improve the imbalance of Th1/Th2 and immunologic derangement caused by Th17 differentiation, inhibit release of TNF-α by macrophages and decrease the level of tumor necrosis factor (TNF)-α, influence inflammation via controlling other inflammatory cytokines. In addition, the mechanism may be concerned with several signal pathways including PGE2 receptor 2 (PGE2-EP2), 5-hydroxytryptamine(5-HT), glucagon-like peptide-2 (GLP-2) and nuclear factor kappa-B-interleukin-6- signal transducer and activator of transcription 3 (NF-κB-IL-6-STAT3). Thus, it is necessary to further investigate the regulation and mechanism of NSAIDs on various immunocytes, potentially provide a new strategy to optimize immune funtions under trauma and disease.

Objective To establish a method combining QuEChERS and ultra-high liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） for rapid screening and testing of three types of new psychoactive tryptamines in human blood： 5-MeO-DALT, 5-MeO-MiPT and 5-MeO-DiPT. Methods The effects of the type of extractant, the type and dosage of salting-out agent, and the dosage of adsorbent on the test results of the three tryptamines were investigated. Blood samples were processed by QuEChERS method and then determined by UPLC-MS/MS. Results The linear relationships of 5-MeO-DALT, 5-MeO-MiPT and 5-MeO-DiPT in human blood were good in the range of 0.5-100, 0.5-100 and 0.2-100 ng/mL, respectively, with their coefficients higher than 0.99. The limits of detection （LODs） were 0.1-0.2 ng/mg. The recoveries ranged from 84.86% to 94.57%. Intra-day and inter-day precisions were good. Conclusion The method is simple, rapid, easy to operate and has a high recovery. It is suitable for the qualitative and quantitative study of tryptamines in blood and can provide the reference for public security organs to deal with related cases.

Objective: To evaluate the image quality of brain MRI sequences accelerated by constellation shuttling imaging (uCS) to provide a basis for clinical application. Methods: Twenty volunteers underwent brain MRI scanning （TSE axial T1WI, T2-FLAIR, sagittal T1WI and GRE sagittal 3D-T1WI） twice using parallel imaging (routine scanning) and corresponding uCS accelerated acquisition. The evaluation of images in each sequence was conducted through combining the subjective (Likert five-point scale method, image artifact and overall quality) and objective (signal-to-noise ratio measurement) methods. Results: The scanning time of using uCS in each MRI sequence was shorter than that of conventional scanning. The total scanning time of uCS in each volunteer was 542 s, while that of conventional scanning was 735 s, which decreased 26.3%. The scanning time of 3D sequence was nearly reduced 39%. There is no statistically difference between uCS and conventional sequence in subjective evaluation (overall image quality and image artifact degree). The SNR of uCS axial T1WI and sagittal T1WI sequences was significantly higher than those of conventional axial T1WI and sagittal T1WI sequences(P

The performance of content-based image retrieval(CBIR) system mainly depends on two key technologies:image feature extraction and image feature matching.In this paper,the color features of all the images are extracted,and an appropriate fuzzy algorithm is adopted in the process of color feature extraction to gain the fuzzy color features of image.Image feature ma-tching mainly depends on the similarity between two image feature vectors.In this paper,a novel fuzzy similarity measure method is proposed it adopts the similarity between the query image and its k nearest neighbor images to constitute the k-dimensional fuzzy feature vector of the query imagem,and adopts the similarity between each retrieved image and k nearest neighbor images of the query image to constitute the k-dimensional fuzzy feature vector of each retrieved image.Then it calculates the fuzzy similarity between the k-dimensional fuzzy feature vector of the query image and the k-dimensional fuzzy feature vector of each retrieved image,and the retrieved images are fed back to users in reverse order of the fuzzy similarity.In order to verify the effectiveness of the proposed fuzzy color features,a series of experimental comparison are performed on the WANG dataset.In order to evaluate the performance of the image retrieval system based on different similarities,a series of experimental comparison are performed on WANG,Corel-5k and Corel-10K datasets.Experimental results show that the performance of the image retrieval system based on the maximum and minimum value outperforms that of the image retrieval systems based on the other three commonly used similarities.And the performance of the image retrieval system based on fuzzy similarity outperformsthat of the image retrieval system based on the maximum and minimum value.On the WANG,Corel-5k and Corel-10K datasets,the average precision of top 20 images retrieved by the image retrieval system based on fuzzy similarity is 4.92%,17.11% and 19.48% higher thanthat of top 20 images retrieved by the image retrieval system based on the maximum and minimum value respectively,and the average precision of top 100 images retrieved by the image retrieval system based on fuzzy similarity is 4.94%,22.61% and 33.02% higher that than of top 100 images retrieved by the image retrieval system based on the maximum and minimum value respectively.

Traditional class action recognition methods focus on the recognition of interactive behavior itself,not the group discovery.Accurate positioning and discovery of interactive groups in class environment is the basis for further individual behavior recognition,but there is a problem of missing behavior data caused by occlusion.Skeletal data represent human behavior and motion trajectory,and have the advantages of not being disturbed by light and background,and simple data expression.Aiming at multi-person interactive group discovery of skeleton data,an interactive group discovery algorithm based on skeleton trajectory aggregation (IGSTA) is proposed.Firstly,this paper standardizes the skeleton data into the human-centered coordinate system to reduce the impact on recognition accuracy of different body size and initial position of person.Secondly,a skeleton trajectory aggregation model based on multi-core representation is proposed to accurately describe the changes of students' interactive beha-vior groups.Finally,the aggregated skeleton trajectories are clustered to realize the discovery of interactive group.Kinect is used to obtain the simulated video of classroom student interaction behavior.Experiments proves the validity of the method,that is,in the case of missing skeleton nodes,the interaction group of students can be accurately found in class environment.

In conventional airfoil optimization design method, the aerodynamic performance of the optimal airfoil can deteriorate at the non-design point, so it is necessary to study the airfoil robust optimization method.An airfoil robustness design method based on convolutional neural network and polynomial chaos method is proposed.Firstly, an aerodynamic force prediction method based on convolutional neural network model is established.And then, the polynomial chaos method is used to perform the uncertainty quantification for mach number and attack angle, a design system of airfoil robust aerodynamic optimization is constructed.Finally, the optimization design verification is carried out for the aerodynamic optimization design problem, in which the RAE2822 airfoil is taken as the basis airfoil.The results show that the robustness design method of the airfoil proposed in this paper is feasible, the optimized airfoil aerodynamic performance and robust aerodynamic optimization design efficiency are improved in a wide design range.

Regional geochemical prospecting data contains a lot of geological information. Extracting the geological spatial distributing information contained in these data is of great significance for regional geological research and mineral prospecting. Regional geochemical data usually includes dozens of elements, which belong to high-dimensional data. Geological spatial distributing information hidden in these high-dimensional data cannot be observed directly from the data. In order to solve this problem, we constructed a dimensionality reduction and visualization model of high-dimensional regional geochemical exploration data based on the t-Distributed Stochastic Neighbor Embedding (t-SNE) algorithm. t-SNE algorithm is a nonlinear dimensionality reduction method, which is especially suitable for dimensionality reduction and visualization of high-dimensional data. Select the elements that are sufficiently stable in lithology identification. Reduce the dimension of high-dimensional geochemical exploration data to 1D, 2D or 3D through the t-SNE algorithm, because the low-dimensional data less than 3D can be observed by human eyes easily. Express the output variables of dimension reduction algorithm as raster files, and visualize them by RGB color mixing and other methods, thus the spatial distribution information of geological bodies hidden in high-dimensional geochemical exploration data can be observed directly. The regional geochemical exploration data of stream sediments in a region of southwest England are taken as an example to evaluate the t-SNE algorithm in visualization of high-dimensional geochemical exploration data. The case study shows that: (1) The high-dimensional geochemical exploration data visualization results through t-SNE algorithm can represent the spatial distribution of geological bodies in the study area very well; (2) The visualization results are tightly related to two parameters: target dimension and perplexity of the t-SNE algorithm. The higher the target dimension was be reduced in the t-SNE algorithm, the more detailed the geological spatial information displayed. (3) The results of dimension reduction and visualization of geochemical exploration data based on the t-SNE algorithm are better than those based on principal component analysis (PCA). The research in this paper shows that the high-dimensional geochemical exploration data visualization method based on the t-SNE algorithm can display the spatial distribution information of geological bodies, which has certain guiding significance for inferring the spatial distribution of geological bodies.

The quantum chromodynamics (QCD) phase diagram is of great interest to researchers in the field of high energy nuclear physics. We review the present research status of several aspects of this topic. This review includes the search for the phase transition mechanism resulting in high-order baryon number fluctuations, how chiral imbalance, finite volume, and under rotations affect the QCD diagram, and the applications of the equation of states of dense QCD matter in the study of compact stars. The Nambu-Jona-Lasinio model and Dyson-Schwinger equations approach are the most commonly used methods described in this review. It is found that the theoretical results of high-order baryon number fluctuations are in good agreement with the experimental data. The chiral imbalance, finite volume, and rotation of quark-gluon plasma (QGP) have a quantitative impact on the chiral condensate and the QCD phase structure. In the study of compact stars, the theoretical results from equation of states of dense QCD matter agree well with pulsar observations. Further research will be required to form a complete understanding of the QCD phase diagram, particularly given the abundance of QGP.

Objective To explore the osteogenic activity of polyetheretherketone/58S bioactive glasses (PEEK/58S) as a kind of bone implant. Methods MG-63 osteoblasts were cultured on PEEK and PEEK/58S surfaces for predetermined time. Then MG-63 osteoblast attachment and spreading condition were observed by scanning electron microscopy (SEM). The proliferation activity of MG-63 osteoblast was evaluated by CCK-8 (cell counting kit). Alkaline phosphatase (ALP) activity was measured to determine the osteogenic differentiation of MG-63 osteoblast. The mRNA expression levels of osteogenesis-related genes ALP, BMP-2, COL-I, OCN and OPN were detected using real-time fluorescent quantitative PCR. Osseointegration of PEEK and PEEK/58S bone implant was evaluated by histological analysis and biomechanical pull-out tests after implantation in a rat tibia model for 12 weeks. Results Compared with the PEEK, the adhesion and spreading of MG-63 osteoblast was more favorable. The proliferation activity and ALP activity of MG-63 osteoblast was significantly promoted (P＜0.05). Also, the mRNA expression of ALP, BMP-2, COL-I, OCN and OPN was significantly up-regulated (P＜0.05). In vivo experiments showed that PEEK/58S exhibited better osseointegration than pure PEEK. Conclusions PEEK/58S bone implant significantly improves the attachment, spreading, proliferation and differentiation of osteoblast and enhances the peri-implant osseointegration, so it is a potential novel orthopedic material for clinical use.

Aimed at the problem of the compressors of the low temperature air source heat pump system, this paper analyzes the impact of volume ratio on performance and proposes a novel three-cylinder two-stage variable volume ratio rotary compressor. The performance of the proposed compression system is compared with that of the traditional two-stage compression system of the same terminal in the experiments. The results show that the three-cylinder two-stage system operates in a stable manner with a coefficient of performance (COP) of 1.52 at a ambient temperature of -30 ℃,while the traditional two-stage system does not work. The COP of the three-cylinder two-stage system is always 1.25% to 12.41% higher than that of the traditional two-stage systems at any ambient temperature. When the ambient temperature is stable and the water supply temperature increases, the amount of dissipated heat at the terminal increases. At the same time, the maximum heat of external machine decreases, as well as the COP. When the ambient temperature is 7 ℃ and -25 ℃ respectively, and the water supply temperature changes from 40 ℃ to 55 ℃,the COP of the three-cylinder two-stage system is 1.15% to 8.86% and 4.32% to 7.33% higher than that of the traditional two-stage system, respectively. The power consumption of the three-cylinder two-stage system is always 3.78% to 16.67% lower than that of the traditional two-stage system.

BACKGROUND Currently the analysis methods of organochlorine pesticides and pyrethroids in environment samples are gas chromatography and gas chromatography-mass spectrometry (GC-MS). Gas chromatography with electron capture detector has been widely used in the study of environmental behavior of pollutants due to its high sensitivity. GC-MS has good qualitative results, but the detection sensitivity is relatively low. OBJECTIVES To establish an easy, highly efficient and precise method for determination of 20 organochlorine pesticides and 4 pyrethroids in complicated matrix soils. METHODS The residues of organochlorine pesticides and pyrethroids in samples from Jiangsu Province in 2018 were studied. In order to improve the qualitative accuracy and ensure the detection sensitivity, a comprehensive two-dimensional gas chromatography-electron capture detector detection method for determination of 20 organochlorine pesticides and 4 pyrethroids in complex-matrix soils was established. TG-35MS column (30m×0.25mm×0.25μm) was chosen as the column for the first dimension, and a DB-1 column (0.8m×0.18mm×0.18μm) was chosen as the column for the second dimension. The fresh sample was mixed with anhydrous sodium sulfate and extracted with hexane-acetone (1:1, V/V), subsequently purified by activated sheet copper. The analysis was conducted by GC×GC-μECD, qualified by retention time and quantified by external standard. RESULTS The proposed method showed good linearity with correlation coefficients (r) higher than 0.995 in the concentration range of 1.0-500μg/L, with the detection limits of 0.02-0.17μg/kg. The recovery of standard addition method ranged from 80.7% to 103.5%, and the relative standard deviations (n=6) were 1.84%-10.12%. CONCLUSIONS The proposed method combined high sensitivity detector with comprehensive two-dimension gas chromatography overcomes the matrix interference in complex sample, which shows a good detection sensitivity and peak capacity. The detection limit of the method is far lower than that of HJ 835-2017 standard (0.02-0.09). This method can provide reference for the analysis of multiple organochlorine pesticides and pyrethroids in complex-matrix soil.

The cobalt hydroxides were in situ synthesized via hydrothermal method with carbon fiber derived from cotton as substrate using cobalt nitrate as cobalt precursor and hexamethylenetetramine as precipitation agent. The morphology and structure of the materials were characterized by scanning electron microscope(SEM), X-ray diffraction(XRD) and IR spectra, respectively. The electroch-emical performance of the samples was analyzed by electrochemical tests such as cyclic voltammetry, galvanostatic charge and discharge and AC impedance. The XRD and SEM results show that, the obtained cobalt hydroxide grown in situ on the carbon fiber substrate is flower-like and α-phase. The electrochemical performance tests display that the specific capacitance of the flower-like cobalt hydroxide is 650 F/g at the current density of 1 A/g, and the retention rate of 67% can be kept with the current density of 10 A/g. The above results illustrate that the flower-like cobalt hydroxide has excellent electrochemical performance, mainly due to its unique structure and morphology, which significantly improves the stability of the electrode material, the diffusion rate of ions and the transport efficiency of electrons.

Intermediate Fluid Vaporizer (IFV) is a key heat exchange device for off-shore floating LNG receiving terminals. Based on the heat transfer theory, a coupled heat exchange calculation model for multiple heat exchangers was established, and mixed working fluid was used as an intermediate medium to study the influence of operating parameters on the heat exchange performance of the gasifier. By analyzing the influence of the saturation temperature of the mixed intermediate medium on the heat exchange performance of the vaporizer, combined with the sensitivity analysis of seawater temperature fluctuations, the optimal saturation temperature range of the mixed intermediate medium is 256-265 K. As the total heat exchange area is small and the change is not vulnerable to seawater temperature fluctuation, the IFV will operate more stably under such condition. Thanks to the high heat exchange coefficient of evaporator and condenser, the IFV will have good heat exchange performance. By studying the influence of the temperature drop of seawater in the thermostat on the heat exchange performance of IFV, the temperature drop range of seawater in the thermostat is 0.6–1.2 K. At this time, the UA value of each IFV, i.e., the product of heat exchange thermal coefficient U and heat exchange area A, and heat load both show high volume, the heat flux density is high, the heat exchangers have good heat exchange performance, and the change on the total heat exchange area of IFV is controlled within 10% of the minimum heat transfer area, each heat exchange accounts for 20% to 50%, which is more conducive to improving the stability and adaptability of IFV operation, and the recommended heat load ratio between heat exchangers is 3–7.

There was a gap between the level of clinical performance /research in Western China and that in Eastern China. Through the investigation and comparison of the staff composition, beds number and research publication in the Department of Otolaryngology of two affiliated hospitals of Western and Eastern medical colleges in 2020, the weakness and barriers of medical personnel in Western China were found out. The regular Journal Clubs(JCs) is an effective method which may stimulate the interest of faculty at hospital in clinical research, enhance research level and arouse the enthusiasm of paper publication with extensive view of latest medical progress and improve the quality of healthcare service.