Search

ObjectivesDistributed photovoltaic power prediction is of great significance for the operation and scheduling of photovoltaic power plants. Point prediction methods are difficult to comprehensively describe the uncertainty of distributed photovoltaic power. This article proposed a distributed photovoltaic power interval prediction model based on complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and sparrow search algorithm optimized least squares support vector machine (SSA-LSSVM).MethodsFirstly, the photovoltaic sequence was broken down into multimodal components through CEEMDAN, and then the high-frequency non-stationary components obtained from the first decomposition were decomposed twice. Secondly, sample entropy (SE) was used to reconstruct all components into trend and oscillation components. Then, the point prediction values of the two components were obtained through SSA-LSSVM. Finally, the probability density estimation was performed on the point prediction error of the oscillation component, and the stacked point prediction value was used to obtain the overall prediction interval result.ResultsThe interval prediction model proposed in this paper has higher interval coverage and narrower average interval width.ConclusionsAdding secondary modal decomposition to distributed photovoltaic power data processing and combining sample entropy to reconstruct its sub-sequences can effectively reduce the complexity of the original prediction components and improve the accuracy of model prediction.

Objective To determine the effect of enamel matrix derivative (EMD) on remineralization of artificial root dentin caries. Methods Bovine root dentin blocks were placed in a demineralization solution to create artificial root dentin carious lesions. The lesions were then randomly divided into EMD group (30 g/L EMD, the experimental group), sodium fluoride (NaF) aqueous solution group (1 g/L NaF, the positive control group) and distilled and deionised water (DDW) group (the negative control group), and all the lesions were pH-cycled at 6 cycles per day for 8 d. Morphology of the lesions were observed by scanning electron microscopy (SEM) and polarized light microscopy (PLM). Transverse microradiography (TMR) was used to examine mineral loss, lesion depth and mineral content. Results After pH-cycling, the surface morphology by SEM and the vertical morphology by PLM suggested that EMD and NaF treatment, but not DDW, caused mineral accumulation of artificial root dentin caries. Meanwhile, TMR revealed significantly lower mineral loss, shallower lesion depth and more mineral content in the EMD group than the DDW group (P < 0.05) after pH-cycling. Conclusion EMD can significantly promote remineralization of root dentin caries in vitro, and is a promising agent for non-invasive root caries therapy. [Key words] enamel matrix derivative , root caries , root dentin ,remineralization ,

In order to clarify the controlling effect of different packaging materials on common storage pests, the penetration and survival of 7 kinds of high density polyethylene films with different concentrations of deltamethrin by the larvae of 3 common species of stored grain pests (Tribolium castaneum (Herbst), Tribolium confusum Duval and Lasioderma serricorne (Fabricius)) were investigated after being treated by two penetration methods for different times at 27~29 ℃ and 70%~80% RH. The results showed that all the tested new insect-proof films had certain insect resistance capabilities, which were different based on species of stored grain insects. In addition, the insect resistance capability of the 6 kinds of new films containing chemicals was higher than that of the control films after 9 days of treatment, and the anti-penetration rate of 1% A (HDPE particle containing 5% deltamethrin by mass) film, 3% A film, 1% B (HDPE particle containing 5% deltamethrin and 2% isoethers by mass) film and 3% B film was 100% under two penetration modes. The survival rate of all three species larvae decreased with increasing treatment time. After 9 days of parallel penetration treatment, the survival rate of three species of larvae on 3%B film was significantly lower than that of other films, and the survival rate of L. serricorne larvae reduced to 10% at the lowest. According to the penetration resistance and larvae survival rate of the test insects on the films, 3% B film had the best insect control effectiveness.

A semiconductor nanomaterial was prepared and its degradation efficiency on zearalenone (ZEN) was investigated. The photocatalytic material, graphitic carbon nitride (g-C3N4), was synthesized by the conventional thermal cracking method, and its structure was analyzed by (X-ray diffraction) XRD, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic degradation experiments showed that g-C3N4 induced photocatalytic effects under ultraviolet light (254 nm, including 185 nm), releasing reactive oxygen radicals to degrade ZEN. The experimental conditions for the photocatalytic degradation of ZEN were explored. The results showed that the degradation rate of ZEN was 96.0% when the mass of the photocatalytic material , the wavelength of the UV lamp, the initial concentration and the irradiation time were 20 mg, 254 nm (50 W), 0.5 μg/mL and 60 min, respectively. Meanwhile, the experimental conditions for the photocatalytic degradation of ZEN powder samples were optimized. The results showed that the degradation rate of ZEN was 80.0% when the mass of the photocatalytic material, the wavelength of the UV lamp, and the irradiation time were 800 mg, 254 nm (50 W) and 50 min, respectively. The results could provide a theoretical reference and practical basis for the photocatalytic degradation of ZEN.

Fusarium infection of wheat can lead to scab, mycotoxin contamination and yield reduction. Fusarium is a serious threat to food security. In this study, the Fusarium strains in wheat were isolated and identified. The three strains N1, N2 and N3 belonged to Fusarium graminearum, Fusarium asiaticum and Fusarium culmatum, respectively. The production of zearalenone, vomitoxin and fumonisin by the three strains was analyzed by toxin-producing gene detection and mycotoxin detection. The results showed that N1 and N3 could produce zearalenone and vomitoxin, but did not produce fumonisin, while N2 did not produce these three toxins. In this study, ozone and chlorine dioxide were further used for gas fumigation to explore the effect of gas fumigation on the three strains isolated. By observing the spore morphology, mycelium length and mycelium morphology, the results showed that chlorine dioxide fumigation could effectively inhibit the growth of mycelium and spore germination, while ozone could only inhibit spore germination and had no obvious inhibitory effect on the growth of mycelium.

The tumor tissue of craniopharyngioma is closely adherent to peripheral neurovascular tissue, so the operation to remove lesion is more difficult, the perioperative complications are very serious, and the prognosis of patients is poor. There are many studies on the use of tumor histology or anatomical classification to guide surgical principles and surgical approaches, as well as drug therapy or combination therapy, but no consensus has been reached. This paper reviews the histological, anatomical and molecular typing of craniopharyngioma, providing new ideas for the future realization of the fusion typing of craniopharyngioma to guide the precise treatment.

To synthesize a class of 2T2R parallel mechanisms with optimal transmission and large tilting ability, a type synthesis method for parallel mechanisms is proposed by combining the screw theory and the limb construction method. Taking the 2-RPS mechanism as the basic limb, the screw theory is used to classify the constraint types of the new limb, and the limb construction criterion is given to ensure that the degrees of freedom of the parallel mechanism remain unchanged. Combined with the characteristics of motion/force transmission of the mechanism, the limb with the maximum transmission index is selected by using the screw theory, and the 2T2R parallel mechanism with the optimal transmission is synthesized. Finally, the kinematics analysis of a novel 2-RPS-UPS parallel mechanism is carried out, and the workspace of the mechanism is solved by Matlab. The results show that the synthesized parallel mechanism has optimal transmission and large tilting ability.

Human corneal endothelial cells (HCECs) are very important for maintaining corneal transparency, but HCECs remain arrested at the G1 phase after embryonic development and could not proliferate and regenerate in vivo. The density of HCECs decreases spontaneously with corneal development and aging, while systemic factors and corneal diseases can further cause a massive loss to HCECs, lead to corneal opacity and edema and ultimately induce vision impairment. Therefore, the regeneration of HCECs has always been a heated topic in the field of corneal endothelial research. Currently, function restoration of exogenous corneal endothelium mediated by cell therapy and autologous regeneration of endogenous HCECs have made amazing breakthroughs, with endogenous HCECs autologous regeneration being a more convenient and physiological treatment option. This review summarizes and analyzes the strategies and related techniques that are currently applied to the autologous regeneration of HCECs in aspects of operative treatment, gene therapy and pharmacological treatment.

As an important part of the power Internet of things, the distribution field area network is the "last mile" infrastructure of the power Internet of things. It can solve the communication problem of the last mile of the power Internet of things. In order to meet the high real-time and high reliability requirements of distribution field area network control services and improve the coverage and reliability of the network, a highly reliable and fast routing optimization algorithm based on Dijkstra algorithm is proposed. The field high-speed power line carrier and radio frequency communication methods of the field area network have complementary advantages. The nodes select the most reliable communication link to transmit data through the hybrid routing table, and consider the reliability and real-time constraints at the same time. The simulation results show that the high-reliability routing optimization algorithm of the distribution field area network can effectively increase the coverage capacity, the number of successfully transmitted services and the average routing reliability.

Objective To summarize the clinical and imaging characteristics with Dandy-Walker syndrome (DWS) in children before and after peritoneal shunt. Methods and Results All 6 children with DWS admitted to Fujian Sanbo Funeng Brain Hospital from January 2016 to January 2023 were selected as the objects of observation, including one case of Dandy-Walker malformation (DWM) and 5 cases of Dandy- Walker variant (DWV). Before surgery, the main manifestations were cerebellar vermis defect, upward movement of the tentorial and sinusional area, severe dilatation of the fourth ventricle, posterior cranial fossa cystic lesions, supratentorial ventricle dilatation and hydrocephalus (one case); or cerebellar vermis dysplasia, cerebellar hemisphere compression, the fourth ventricle dilatation, posterior cranial fossa cystic lesions, supratentorial ventricle dilatation and hydrocephalus (5 cases). Right lateral ventriculoperitoneal shunt (2 cases) or posterior cranial fossa cyst-peritoneal shunt (4 cases) were performed, and the operations were successful without surgery - related complications. After 2.31-7.00 years of follow - up, 6 cases of hydrocephalus and posterior cranial fossa cystic malformation were gradually relieved, 3 cases of good prognosis, cerebral hemisphere and cerebellum development, speech, movement and intelligence normal; there were 3 children with general prognosis, including cerebellar disequilibrium symptoms (one case), autism, claustrophobia (one case), and speech, motor and intellectual disorders (one case) complicated with neurocutaneous melanosis. Conclusions The brain structure of the children with DWS presented with hydrocephalus can be well developed after the hydrocephalus is corrected by single shunt. Among them, the cerebellar vermis of the DWV is well developed, while the development of the DWM presented with cerebellar vermis defect needs to be observed in more cases.

Objective: Construction of a simple and rapid method for the analysis of ganoderic acid A （GAA）. Methods: The molecular imprinted polymer （MIP） that can specifically recognize ganoderic acid A （GAA） were prepared by cyclic voltammetric deposition using GAA as template molecule and o-phenylenediamine as functional monomer. The structure, morphology and electrochemical behavior of MIP were characterized by infrared spectroscopy, scanning electron microscopy and electrochemical methods. Using [Fe（CN）6]3-/4- as the active indicator, the analytical performance of the sensor for GAA was investigated. Porous MIP for GAA can be prepared on the electrode surface by one-step electropolymerization. Results: The results of quantitative analysis showed that the electrochemical signal of [Fe（CN）6]3-/4- had a good linear relationship with the logarithm of GAA concentration in the range of 1.0 pmol/L～1.0 μmol/L, and the detection limit was 0.21 pmol/L. The measured values of GAA in ethanol and water-soluble solution of Ganoderma lucidum powder were 1.15 nmol/L and 3.00 pmol/L, respectively. Conclusion: The MIP-based GAA electrochemical sensor can be used for the rapid determination of GAA in extract solution of Ganoderma lucidum powder.

In order to rapidly determine aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) in maize, a AFB1-ZEN-DON three-in-one combined detection method has been established. This quantitative immunofluorescence assay based on superconductor coating was used to detect multiple maize samples. Combined with the recovery rate, stability, detection limit, precision and other indexes, the applicability of the method were evaluated and compared with the results of liquid chromatography. The results showed that the AFB1-ZEN-DON three-in-one combined detection method had the good linearity in the range of 0.5~30 µg/mL for AFB1, 5~200 µg/kg for ZEN and 100~2 500 µg/mL for DON, respectively. The relative deviation of AFB1, ZEN and DON detected by this method was –2.84%~11.91%, –3.43%~18.12% and 1.83%~12.91%, respectively, which were within the allowable deviation of 20%, 15% and 23%. The detection limit of AFB1 was 0.41 μg/kg and the corresponding limit of quantification was 1.12 μg/kg. The limit of detection of ZEN was 3.22 μg/kg and the corresponding limit of quantitation was 9.15 μg/kg. The detection limit of DON was 35.42 μg/kg and the corresponding limit of quantitation was 100.84 μg/kg. Compared with the results of liquid chromatography, the superconductor coated immunofluorescence test strip method is an effective, practical, rapid and quantitative analysis method within the allowable deviation range, suggesting that it could meet the requirements of simultaneous detection of AFB1, ZEN and DON in maize.

Bone development shows certain regularity with age. The regularity can be used to infer age and serve many fields such as justice， medicine， archaeology， etc. As a non-invasive evaluation method of the epiphyseal development stage， MRI is widely used in living age estimation. In recent years， the rapid development of machine learning has significantly improved the effectiveness and reliability of living age estimation， which is one of the main development directions of current research. This paper summarizes the analysis methods of age estimation by knee joint MRI， introduces the current research trends， and future application trend.

Objective: This study aimed to improve the production technology and flavor of Chinese beef sauce. Methods: Compared with traditional static curing, the effects of breathing rolling curing on volatile components of beef were analyzed by SPME/GC-MS. Results: The main aroma components of the beef in breathing rolling and curing process were the same as those in traditional static state, which were mainly aldehydes, hydrocarbons, alcohols, esters and ketones, among which the representative substances were benzaldehyde, anisene, cineol, eugenol acetate and 2-butanone. There were some differences in the types and relative contents of volatile substances, among which the number of hydrocarbons was significantly higher than that of other substances. There were 23 kinds of hydrocarbons in the traditional static pickled beef, and only 11 kinds of hydrocarbons in the breathing rolling pickled beef were significantly lower than that in the control group. The relative content of aldehydes, as the main flavor source of the sauce beef, was significantly higher than that of other substances, which were 37.48% and 34.28% in the two curing methods, respectively. The alcohols in soy beef mainly come from spicy seasoning. The ester compounds in beef were increased and their relative contents were also increased with the breathing rolling and kneading curing. The results of GC-MS analysis showed that there was significant difference between the aroma characteristics of the beef processed by breathing rolling curing and traditional static curing. Conclusion: SPME/GC-MS can be used to analyze and compare volatile substances in beef with different curing methods.

ObjectiveTo develop plasmid DNA reference materials that can be used for polymyxin antibiotic resistance encoding genes rapid detection.MethodsThe reference sequence of mcr­1， mcr­3 and mcr­5 were retrieved from the National Center for Biotechnology Information to construct recombinant plasmids and strains. The recombinant strains were subcultured for 15 generations to detect the genetic stability of the target gene. The recombinant plasmid was extracted and vacuum dried to prepare the standard sample. The limit of detection （LOD） of PCR and RT­qPCR was determined after the standard sample was hydrated and continuously diluted with 10­fold gradient， respectively. Multi­tube plasmid DNA standard samples were randomly selected to qualitatively and quantitatively evaluate the uniformity and storage stability at 4 ℃， 37 ℃ and -20 ℃ by PCR and UV spectrophotometer.ResultsFragments of mcr­1， mcr­3 and mcr­5 that encoding polymyxin resistance mechanism were successfully obtained. Target genes in the recombinant strains could stably inherited after subcultured for 15 generations. The LOD of PCR and RT­qPCR of mcr­1， mcr­3 and mcr­5 standard samples were 1.67×104 and 1.67 copies/μL， 1.31×104 and 13.1 copies/μL， 1.55×105 and 1.55 copies/μL， respectively. The mass F values of 12 standard samples randomly selected for each gene were all less than the F critical value， each gene could be detected by RT­qPCR and indicating that the uniformity of the samples met the requirements. When standard samples were stored at 4 ℃ for 90 d， 37 ℃ for 14 d and -20 ℃ for 360 d， the qualitative and quantitative test result showed it was stable without significant difference.ConclusionIn this study， plasmid DNA standard samples that carrying mcr­1， mcr­3 and mcr­5 were prepared. The target genes could be stably inherited， the standard samples had good uniformity and storage stability， and could be used as a quality control samples for polymyxin antibiotics resistance encoding genes detection and mechanisms prediction.

Grain freshness is affected by various factors in the environment during the process of storage, and its quality will change as time goes by. Therefore, the identification of freshness of grain is an indispensable and important in grain storage. However, in the grain industry, there has been no standard national method to indetify the freshness of grain. This paper summarizes common identification methods of the freshness of grain, and looks out to the future developments and researches, so as to provide references for people who work in the grain industry.

At present,recommendation system has been widely used in our life,which greatly facilitates people's life.The traditional recommendation method mainly analyzes the interaction between users and items and considers the history of users and items,and only obtains the user's preference for items in the past.The sequential recommendation system,by analyzing the interaction sequence of items in the recent period of time and considering the relevance between the user's previous and subsequent behaviors,can obtain user's preference for items in short term.It emphasizes the short-term connection between user and item,while ignoring the relationship between the attributes of the item.Aiming at the above problems,this paper presents a convolutional embedding recommendation with time and user preference (CERTU) model.This model can analyze the relations between items.It can obtain dynamic changes in user preferences.The model also considers the influence of individual item and multiple items to the next item.Experiments show that the performance of CERTU model is better than that of the current baseline method.

Objective To screen the differentially expressed (DE) coding and non-coding RNAs in human vitiligo melanocytes and analyze their interactions and verify the expression of the identified key RNAs in order to explore their possible role in the pathogenesis of vitiligo. Methods High throughput sequencing was performed on human vitiligo melanocyte lines and normal human melanocyte lines. DE analysis was performed by R software. Protein-protein interaction (PPI) network was constructed by using the search tool STRING. The interaction loop of miRNA-mRNA and miRNA-lncRNA was identified by bioinformatics algorithm miRanda. The competitive endogenous RNA (CeRNA) network was constructed by Cytoscape software, and the functional enrichment and pathway analysis of DE mRNAs were performed by David database. Finally, the identified key RNAs were verified by Q-PCR. Results A total of 5 958 DE mRNAs, 1 650 DE lncRNAs and 450 DE miRNAs were screened out by DE analysis. The top10 hub genes (JUN, HIST2H3PS2, SOX2, EGR1, MMP9, NGF, BMP2, HSPA5, EDN1 and SERPINE1) in the PPI network are indicated closely related to the pathogenesis of vitiligo. Furthermore, 7 key lncRNAs that interact with top 20 hub genes are found. Among them, 3 lncRNAs (ENST0000623111, NONHSAT245258.1 and NONHSAT189782.1) with the most abundant molecular functions and signaling pathways were constructed into CeRNA subnetwork, and the expression of hsa-miR-92b-5p predicted in the CeRNA sub-network is significantly different in vitiligo melanocytes. In addition, the results of Q-PCR were basically consistent with our analysis. Conclusion The identified hub genes and non-coding RNAs in our study may play important roles in the pathogenesis of vitiligo. Our findings provide novel insights and strategies for researches on vitiligo.

Objective To investigate the effect of neurophysiological monitoring in extended endoscopic transsphenoidal surgery for cavernous sinus and clivus tumors. Methods We monitored the oculomotor nerve, trochlear nerve, trigeminal nerve and abducent nerve in 18 patients with cavernous sinus and clivus tumors by recording the free⁃electromyography (f⁃EMG) and triggered⁃electromyography (t⁃EMG) from August 2019 to December 2020. Two needle electrodes were inserted percutaneous into the levator palpebrae superioris muscle, superior oblique muscle, extraocular rectus muscle and masticatory muscle. To evaluate spontaneous muscle activity and complex muscle action potentials after cranial nerve stimulation. We evaluated the safety of cranial nerves and provided objective information for neurosurgeon. Results All the 18 patients with cavernous sinus and clivus tumors were treated by extended endoscopic transsphenoidal surgery, including 10 pituitary adenomas, 5 chordomas, 2 craniopharyngiomas and one cystic schwannoma. Total resection rate achieved 9/18, subtotal resection rate was 4/18, and partial resection rate was 5/18. There was no postoperative internal carotid artery (ICA) injury and cerebrospinal fluid leakage. A total of 20 oculomotor nerves, 3 trochlear nerves, 27 trigeminal nerves and 26 abducent nerves were recorded. There were one patient with left abducent nerve palsy and one patient with right abducent nerve paresis before surgery. The median follow⁃up time was 8.63 months, postoperative brain nerve injury occurred in 2 patients, the brain nerve injury rate was 2/18, all of which recovered 3 months after surgery. No patients with postoperative impaired trigeminal nerve function. Conclusions Monitoring of oculomotor nerve, trochlear nerve, trigeminal nerve and abducent nerve in extended endoscopic transsphenoidal surgery for cavernous sinus and clivus tumors is a safe and effective method. By monitoring and evaluating intraoperative f ⁃ EMG and t ⁃ EMG, neurosurgeons can adjust surgical procedures and strategies during tumor resection and reduce cranial nerve injuries.

Objective To investigate the effect of modulating thrombomodulin (TM) expression on renal injury in a rat model of diabetic nephropathy (DN) and explore the possible mechanism. Methods We examined the expression of liver X receptor-α (LXR-α), TM, coagulation factor XⅢ-A (FXⅢ-A) and CD163 in 25 renal biopsy samples from patients with DN and in 6 normal renal tissue specimens using immunohistochemistry. Twenty-four 12-week-old male db/db mice with DN were randomly assigned into 4 equal groups and treated daily with intragastric administration of normal saline or LXR-α agonist T0901317, or with intravenous injection of an adenoviral vector carrying TM shRNA or the control adenoviral vector for 7 consecutive days; 6 wild-type C57BL6 mice with intragastric saline treatment served as the normal control group. Four weeks after the treatment, the expression of TM, LXR-α, FXⅢ-A and CD163 in the renal tissues of the mice were detected using Western blotting, the levels of tumor necrosis factor-α (TNF-α) and interleukine-6 (IL-6) were detected by ELISA, and the urinary microalbumin level was determined. Results The renal expression levels of TM and LXR-α were decreased (P < 0.05) and those of FXⅢ-A and CD163 were increased significantly (P < 0.05) in the kidney tissues of DN patients compared with normal kidney tissues. In db/db mouse model of DN, the expression levels of TM and LXR-α were positively correlated while those of FXⅢ-A and CD163 were negatively correlated with glomerular filtration rate (P < 0.05). Compared with the wild-type mice, the mouse model of DN showed significantly increased urinary microalbumin levels and serum levels of TNF-α and IL-6, lowered renal expressions of TM and LXR-α, and increased renal expression of FXⅢ-A and CD163; these changes were further exacerbated in the mice treated with Ad-TM shRNA (P < 0.05) but significantly improved in the mouse models treated with T0901317. Conclusion Upregulating TM expression can reduce urinary microalbumin level in db/db mouse model of DN by inhibiting the renal expression of FXⅢ-A and CD163 and downregulating blood levels of inflammatory mediators.

Objective To determine the effect of aminopeptidase N (APN) on the proliferation, invasion, and apoptosis in human glioma U251 cells and to investigate the possible mechanism. Methods After APN gene expression was silenced in glioma cells U251 by RNAi, its expression at mRNA and protein levels was detected by RT-qPCR and Western blotting, respectively. Then, CCK-8 assay, flow cytometry, wound healing test and transwell assay were used to detect the proliferation ability, cell cycle and apoptosis, migration and invasion activity in the U251 cells. The protein expression of STAT3 signal pathway proteins t-STAT3, p-STAT3, MMP-2 and Bcl-2 was measured by Western blotting. Results Compared with blank control and NC-siRNA cells, the expression of APN was decreased at mRNA and protein levels in APN-siRNA cells (P < 0.01). Silencing of APN gene also resulted in inhibited proliferation ability (P < 0.05), cell cycle arrested at G0/G1 phase, enhanced apoptotic rate (P < 0.01), and decreased migration and invasion abilities (P < 0.01) in U251 cells. What's more, the inhibited expression of p-STAT3 caused the decreased expression of Bcl-2 and MMP-2 (all P < 0.05). Conclusion Silencing of APN could inhibit the proliferation, migration and invasion, and induce apoptosis in glioma U251 cells via STAT3 signaling pathway.

Objective To compare the surgical efficacy of combined bypass surgery for symptomatic moyamoya disease patients at early and late Suzuki stage, and to preliminarily explore the correlation between operative timing and efficacy. Methods A retrospective analysis was performed on 58 patients (70 hemispheres) with symptomatic moyamoya disease treated with combined bypass surgery in our department from June 2015 to October 2018. According to the results of Suzuki staging system for moyamoya disease, they were divided into early stage group (stage Ⅰ~Ⅲ, 42 hemispheres) and late stage group (stage Ⅳ~Ⅵ, 28 hemispheres). Superficial temporal artery-to-middle cerebral artery bypass with encephalo-duro-myo-synangiosis (STA-MCA bypass+EDMS) were performed for all patients. The perioperative complications, and improvement of symptoms, recurrence of stroke, and prognosis score (Modified Rankin Scale, mRS) in 6 months after the operation were assessed and compared between the 2 groups. Results The incidences of total perioperative complications, cerebral hyperperfusion syndrome and perioperative cerebral hemorrhage was significantly lower in the early stage group than the late stage group (28.6% vs 57.1%, 14.3% vs 35.7%, 0 vs 10.7%, respectively, P < 0.05). There were more patients with mRS score of 0~2 at 6 months after surgery in the early stage group than those in the late stage group (85.7% vs 64.3%, P=0.036). No obvious difference was seen in the improvement rate of postoperative symptoms between the 2 groups (65.6% vs 68.4%, P=0.838). No stroke occurred in the both groups during postoperative follow-up. Conclusion Bypass surgery can not only reduce the incidence of perioperative complications, but also obtain better prognosis for the early Suzuki stage patients with symptomatic moyamoya disease. Early Suzuki stage should be optimal operative time for bypass surgery.

Scalar coupling is an important parameter in nuclear magnetic resonance (NMR). The proton-proton coupling constant JH-H provides valuable information on molecular structure. However, determining JH-H value in complex coupling networks is still challenging. Here, we propose a method called simultaneous multi-slice selective constant-time J-resolved spectroscopy (SMS-SECTJRES) to measure JH-H values of all coupling networks of a molecule simultaneously in one experiment. In this method, gradient-encoded selective refocusing is used during a fixed evolution time, combined with echo planar spectroscopic imaging (EPSI) detection module to extract different selective J-edited spectra in different spatial positions. This new method is conducive to reveal coupling networks and the analysis of molecular structures.

A sol-gel method was applied to prepare xLa-3%(mole fraction,the same below)In-TiO2 photocatalytic materials,which were characterized by XRD, SEM, surface area, and pore size distribution measures. Photocatalytic activity of the materials was also evaluated. The results show that the materials are in tetragonal anatase structure. Crystalline size of TiO2 decreases after doping La and In. In3+ and La3+ exist in TiO2 crystal lattice by substituting Ti4+. La doping results in enlarging surface area and shrinking pore size. Pore size of xLa-3%In-TiO2 is mainly in the range of 1.5-10nm. Doping of La obviously leads to enhanced photocatalytic activity. Photocatalytic rate constants of methyl orange are 0.061min-1 and 0.029min-1 on 0.3%La-3%In-TiO2 and 3%In-TiO2, respectively. The chromogenic groups in methyl orange molecules can be degraded during photocatalytic process.

Most organotin compounds, which have been widely used in food packaging materials and production process show serious toxicity effects on human health. A high content of fat brought large matrix interference to the analysis and detection of edible vegetable oil. Methanol was selected as the extraction solvent, and the edible vegetable oil in low temperature was easily solidified. A simple and low-cost method based on high performance Liquid Chromatography-Tandem Mass Spectrometry for the simultaneous determination of four organotins in edible vegetable oil samples was developed. Four organotins including dibutyltin dichloride, tributyltin chloride, diphenyltin dichloride and triphenyltin chloride were simultaneously extracted with methanol using the low-temperature precipitation process. After being concentrated, the extracts were purified by matrix solid-phase dispersion using graphitized carbon black. Ethanol, methanol, and acetonitrile were investigated to extract organotins from edible vegetable oil samples. The recoveries of the four organotins extracted by liquid-liquid extraction and freezing extraction were also compared. The proposed method is comparable to, or even an improvement on the current national standard and related research. The adsorption abilities of some materials including primary secondary amine, alumina N, florisil, and graphitized carbon black were also studied. In order to evaluate the accuracy of the new method, the recovery was investigated. The ranges in the recoveries for the four organotins present at three levels ranged from 74.2% to 99.5%. Current work is comparable or better than those of national standards and the reported methods. The results show that the sample preparation method enables the simultaneous determination of the four organotins in peanut oil, soybean oil, corn oil, rape oil and edible blended oil samples.

The electromagnetic properties of high-carbon ferrochrome powders(HCFCP) obtained at different cooling rates were investigated by means of the vector network method in the frequency range of 1 to 18 GHz. It is found that both the real part and the imaginary part of the relative complex permittivity of HCFCP show an increasing order with a rising in cooling rate at most frequencies,of which prominent peaks occur in the imaginary part of the air-cooled and water-cooled powders on account of polarization relaxation.For comparison,both the relative complex permeability and magnetic loss factor present complex change histories,where the real part of the relative complex permeability decreases as the cooling rate rises,and the imaginary part of the water-cooled powders occupies the dominant except for the frequency range from 3 to 5 GHz. While peaks in the imaginary part of each cooling sample principally result from the effect of nature resonance and magnetic hysteresis respectively corresponding to low frequency and high frequency. The reflection losses of furnace-cooled,air-cooled and water-cooled HCFCP with the values of -2.30,-2.15 and -2.07 d B severally at 2.45 GHz,could meet the need of microwave heating in principle. By overall consideration,the water-cooled powders are determined as the optimal materials for solid-phase decarburization of HCFCP in a microwave field,attributed to a higher dielectric loss factor as well as a higher magnetic loss factor.

The A-weight sound level is difficult to evaluate the annoyed noise of the inverter air conditioner,so it is necessary to establish the sound quality and give objective evaluate parameters,such as loudness,sharpness,roughness,psychoacoustic annoyance etc. The sound quality software is developed to analyze outdoor noise of MIDEA inverter air conditioner and the competitive product; the main difference is low-frequency noise. Then,the"rock"noise and periodic"buzz"noise are analyzed in detail,and system dynamic balance and beat are main reasons. Some methods are obtained to eliminate the lowfrequency noise and can improve the sound quality. These methods can potentially become a powerful air conditioner sound evaluation tool in inverter air conditioner field.

Based on blockiness and the matter-element extension theory,this article introduces BET method(classification method based on blockiness and the extension theory) especially suitable for roof stability analysis. The integrity of roof rock was reflected by blockiness in three-dimensional space,and an evaluation system was constructed with blockiness,uniaxial compressive strength,joint condition and groundwater condition as evaluating indicators. The classical domain,the segment and the object element of the model were established,the incompatible problems between these indexes were analyzed,and the index weights were calculated by the extension method. After the correlation degree was comprehensively calculated,the stability classification method and standard were determined. Selecting four test areas of fractured rock mass in Guangxi Tongkeng Mine,an engineering application study of BET classification method was carried out. The results of traditional classification methods,such as RMR method,RSR method and Q method,were respectively compared to that of BET method. It is shown that compared with these traditional classification methods,the index system selected by BET method is more comprehensive and its evaluation method is more objective and scientific.

Traditional determination of fluoride and chloride in gypsum and its products has the disadvantages of complicated pretreatment, long detection time, poor accuracy and low sensitivity. To remedy this, an ion chromatography method which can simultaneously determine the fluoride and chloride in gypsum and its products has been successfully developed. The sample was extracted firstly by ultrasonic processing and eluted by Na2CO3-NaHCO3. The solution was then separated by anion column and suppressed by self-electric chemistry suppressor. Finally, the solution was detected using a conductivity detector. By optimizing the pretreatment and separate conditions, the concentrations of the fluoride and chloride have good linear relationships with the peak area in the measured range with correlation coefficients of 0.9999 and 0.9998 for F- and Cl-, respectively. The proposed method yielded the detection limits of 0.15 ng/mL and 0.28 ng/mL for F- and Cl-, respectively, the recovery of 95.0%-99.7% and the RSD of less than 5% (n=8). The proposed method utilizes ultrasonic extraction and avoids purification. The pretreatment can be completed in less than 0.5 h and the loss of target analyte can be avoided. Compared with the ion selective electrode method, the detection limit of this method improves from μg/mL to ng/mL.

In view of problems of high cost and big volume of petroleum gas measuring system by use of imported equipment, the paper proposed a design scheme of measuring system of wellhead gas components of petroleum drilling. The system uses catalytic combustion type gas sensing probe and takes wheatstone bridge as measuring unit. When gas sensing probe meets measured gas, resistances of wheatstone bridge would change with changing of temperature if the gas could be ignited by electrode, so as to obtain gas concentration. Results of measured gas concentration are displayed, stored and generated report automatically through upper computer LabVIEW program. The actual application showed that the system has low cost, convenient operation and sensitive response, whose measured results are synchronous with imported equipment.

An enhancement was proposed that the receiving node feeds back its decoding state to the other nodes.Further,the enhancement can improve the performance of decode-and-forward cooperative diversity.The outage probability and throughput of incremental relay and selection relay were derived in low SNR,and the three-order approximation of out-age probability was presented.Combined with the strong points of incremental relay and selection relay,joint relay was brought forward.The theoretical analysis and numerical simulation reveal that the proposed joint relay has such pre-dominant performances as outage probability and throughput.

Light curing 3D printing technology has become an emerging technology in the manufacturing industry because of its high precision, rapid prototyping, and complex parts can be formed. Photosensitive resin is the main consumable of light curing 3D printing technology, and its mechanical properties, heat resistance, precision and strength are not ideal enough to meet the needs of industrial production. In order to obtain the photosensitive resin with high mechanical strength and function, it must be modified. In this paper, the modification of photosensitive resin for photocuring 3D printing is introduced. Starting with the principle of SLA photocuring rapid prototyping technology, the various components of photosensitive resin are introduced, and the modification of photosensitive resin is shown from the two aspects of reaction type and addition type. Finally, the development trend of photosensitive resin is prospected. It is pointed out that in the future, on the basis of perfecting the existing photosensitive resin materials, more new materials for 3D printing will be developed, resin formula will be expanded, and more in-depth research will be carried out on the modification of photosensitive resins, so as to develop more high-performance, higher-strength, and greener resin systems. [ABSTRACT FROM AUTHOR]

In recent years, the frequent occurrence of urban waterlogging disasters caused by extreme rainfall due to climate change has posed a threat to urban water safety and sustainable development in China. Accurately grasping the public opinion and emotions in the disaster-stricken areas is of great importance for improving the situational awareness capabilities of emergency management departments in dealing with waterlogging disasters. In today's era of intelligent networks, the increasing importance of social media as a platform for people to voice their problems and suggestions has made it a major carrier of public sentiment and societal opinion, providing a new avenue for obtaining information about natural disasters. A key technical challenge that needs to be urgently addressed is how to quickly extract urban flood disaster information from social media, and how to perform thematic categorization and sentiment analysis of natural disaster information to accurately grasp the thematic categories of regional disaster situations and public opinion trends. Taking Sina Weibo as an example, this article elaborates on the methods of collecting and pre-processing flood disaster data, and constructs a thematic classification and sentiment analysis model of urban flood disaster information based on FastText to accurately capture the thematic categories and public opinion orientations of disaster-stricken areas. The research results, using the "7.20" heavy rain and flood disaster in Zhengzhou in 2021 as an example show that the methods proposed in this article achieve intelligent extraction and analysis of urban flood disaster data on social media. The theme classification model achieves an F1 score of over 0.80 for the classification prediction of the eight predefined categories, and the sentiment analysis model is generally able to accurately predict data labelled as "negative" in sentiment, which indicates that the FastText-based urban flood disaster information theme classification and sentiment analysis model constructed in this article can meet the needs of urban emergency management departments to dynamically grasp the development of flood disasters and public emotions. It holds significant guiding importance for flood prevention and disaster mitigation planning, calming public emotions, and pinpointing rescue efforts in real time. [ABSTRACT FROM AUTHOR]

Objective We tried to explore the optimal dose of esketamine combined sevoflurane for the daytime pediatric circumcision. Methods According to the random number table, children who underwent daytime circumcision were randomly divided into Group A (0.5 mL/kg esketamine), Group B (0.75 mL/kgesketamine), and Group C (1mL/kg esketamine) with 30 cases in each group. Each group were induced with sevoflurane inhalation anesthesia by mask and given a single intravenous dose of the corresponding esketamine after the eyelash reflex disappeared. The occurrence of intraoperative movement and esketamine bolus times was recorded. Heart rate (HR), mean arterial pressure (MAP), pulse oxygen saturation (SpO2) and respiratory rate (RR) were monitored at the time of entry (T0), the beginning of surgery (T1), intraoperative ligation (T2) and the end of surgery (T3). The times of opening eyes and talking after surgery were also recorded. Modified Alertness/Sedation Score (MOAA/S score) at 15 min, 30 min and 60 min after surgery, the Eastern Ontario Children's Hospital Pain Score (CHEOPS score), Bieri Modified Facial expression score and verbal rating scale (VRS) score at the time of awakening, 2 h and 6 h after surgery were all recorded. Moreover, intraoperative and postoperative adverse reactions (respiratory depression, laryngeal spasm, agitation, nausea and vomiting, dizziness and diplopia ect.) were all marked. Results The incidence of intraoperative body movement andesketamine bolus times in Group B and C were all less than that in Group A (P < 0.05). The time of opening eyes and talking in Group A and Group B were shorter than those in Group C (P < 0.05). There was no significant difference in intraoperative vital signs, postoperative alertness score and pain score among the 3 groups (P < 0.05). There was no significant difference in the incidence of adverse reactions among the 3 groups (P < 0.05). Conclusion A does of 0.75 mg/kg esketamine combined with sevoflurane could effectively meet the anesthetic and analgesic needs of children's prepuce operation and shorten postoperative recovery time. It is the optimal dose and deserving promotion in daytime pediatric circumcision. [ABSTRACT FROM AUTHOR]

The International Codex Alimentarius Commission (CAC) issued a new version of the general rules on food hygiene in 2020, which revised and improved the structure, definition and technical contents of the standard, clarified the important role of good hygiene practices in food safety management, and emphasized the advantages of Hazard Analysis and Critical Control Point (HACCPL) in dealing with more complex food safety issues. It also added the latest achievements of standardization research in the field of food safety in recent years, such as allergen control and food safety culture. By comparing the new version of the standard with the 2003 edition of general principles of food hygiene, this paper expounds and analyzes the main changes of the new version of the standard in detail, so as to provide reference for the formulation and implementation of food-related standards in China. [ABSTRACT FROM AUTHOR]

Objective To describe the characteristics of commercial sexual behavior of HIV-infected men who have sex with men (MSM) and analyze its influencing factors. Methods An anonymous questionnaire survey was conducted through the recruitment of HIV-infected MSM by two social organizations in Chongqing. The x² test was used to compare the commercial sexual behavior of HIV infected with MSM with different social demographic characteristics, mental health status, and sexual behavioral characteristics. Multivariate Logistic regression model was used to analyze the influencing factors of commercial behavior. Results A total of 1 501 cases of HIV infection with MSM were investigated in this study. In total 12.50% of the respondents reported same-sex commercial sex in the past six months, of which 28.34% reported unprotected commercial sex behavior. The results of multivariate Logistic regression showed HIV-infected MSM with marital status as marriage/cohabitation (OR =2.345, 95%CI: 1.442-3.814), working status as part-time and others (OR=6.522, 95%CI: 3.575-11.900), monthly income exceeding 5 000 yuan (OR=7.890, 95%CI: 4.254-14.634), age of first sexual intercourse less than 18 years old (OR= 1.818, 95%CI: 1.014-3.260), using same-sex dating software (using one: OR=2.984, 95%CI: 1.477-6.030; using two: OR = 3.683, 95%C$: 1.650-8.221; using 3 and above: OR=21.777, 95%CI: 8.349-56.804), drinking (0R=2.528, 95%C$: 1.5684.074), and using Rush (OR=3.114, 95%CI: 1.988-4.877) were more likely to have commercial sexual behavior (P < 0.05). Conclusion The commercial sexual behavior of HIV infection with MSM is common in Chongqing, and the proportion of commercial sexual behavior without condom is high_ Comprehensive measures should be taken to intervene the drinking, Rush use, and commercial sexual behavior of this population in order to reduce the further spread of HIV/STIs. [ABSTRACT FROM AUTHOR]

Jiaguyou 404 was a new combination of high-quality hybrid rice bred by Quanzhou Institute of Agricultural Sciences, which was bred by crossing Jiagu A, a three-line sterile line with good quality and disease resistance, as the female parent and Quanhui 404 as the male parent. The combination had the characteristics of good plant-leaf shape, large panicle and multiple grains, moderate plant height and plant type, high and stable yield, and good rice quality, which was examined and approved by Fujian Crop Variety Approval Committee in 2022. The breeding process, characteristics, high-yield cultivation and seed production technologies of the new hybrid rice combination, namely Jiaguyou 404 were introduced . [ABSTRACT FROM AUTHOR]

In view of the fact that the multi-stage pump type intermediate guide vane designed according to the pump working condition cannot meet the runner's requirements for flow circulation when used in hydraulic turbine devices, the influence of key structural parameters of pump type equal diameter positive and negative guide vanes on water head loss, efficiency and working head of hydraulic turbine devices is studied by combining the hydraulic turbine design theory and CFD numerical simulation. The results show that appropriately increasing the diameter of the inlet edge of the reverse guide vane, chamfering the edge of the baffle, and chamfering the inner and outer walls of the interstage guide vane inlet can reduce the head loss of the inter-stage guide vane and improve the working efficiency of the hydraulic turbine; the shape and number of guide vanes have a significant impact on their outlet water flow velocity circulation; increasing the wrap angle or increasing the number of blades can enhance the forcing effect of the guide vanes on water flow, increase the outlet water circulation, but increase the head loss of the guide vanes. This paper can provide a reference for the design of the same diameter forward and backward guide vanes used in hydraulic turbines. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of hepatitis B virus (HBV) on the expression of type I interferon and its possible mechanism. Methods: HepG2 cells and HBV stably transfected HepG2.2.15 cells were used as the model, cells were transfected with pEGFP-HBx plasmid or HBx-siRNA, the levels of IFN-α and IFN-β mRNA in cells were detected by fluorescence quantitative PCR, and the expression of pEGFP-HBx plasmid in HepG2 cells was observed by fluorescence microscope, the changes of HBx and p-IRF3 protein in cells were analyzed by Western blot, to investigate the effect of HBV on the expression of type I interferon. Results: The levels of IFN-α and IFN-β mRNA in HepG2.2.15 cells were slightly higher than those in HepG2 cells, there was no significant difference (P>0.05); after silencing HBx expression by using RNA interference in HepG2.2.15 cells, the levels of IFN- α and IFN-β mRNA were significantly increased. Moreover, the levels of type I interferon genes expression and p-IRF3 protein expression in HepG2 cells transfected with pEGFP-HBx were both decreased. Conclusion: HBV inhibits the expression of type I interferon by regulating the activation of IRF3 protein through HBx protein. [ABSTRACT FROM AUTHOR]

To achieve simple and reliable single-phase grounding fault protection on the AC side of VSC-HVDC systems， this paper focuses on systems where the neutral point of the converter valve's AC side is impedance-grounded. The zero-sequence fundamental component on the AC side and the common-mode component on the DC side are analyzed， and analytical expressions for the zero-sequence fundamental voltage and current at both the faulted and non-faulted terminals during a metallic grounding fault are derived. For VSC-HVDC systems utilizing third harmonic injection modulation， the phase characteristics of the longitudinal third harmonic voltage induced by this modulation are examined， and expressions for the third harmonic voltage and current are derived. Based on this analysis， protection criteria using the zero-sequence fundamental voltage and third harmonic voltage at neutral point are proposed to detect grounding faults and determine their location， along with the corresponding setting calculation method. Simulation results under various operating conditions show that the protection mechanism correctly activates when a grounding fault occurs at the protection installation terminal and does not operate erroneously when faults occur at other terminals.

Objective To conduct hazard vulnerability analysis(HVA) in a blood bank, aimed to identify high-risk events and optimize emergency management measures. Methods The risk event evaluation index system was established by referring to the Kaiser model and the situation of Guangzhou Blood Center, and risk events were ranked by risk matrix and Borda count. Results The top five events with the highest risk values identified by Kaiser model were information system emergencies (39.61%), extreme weather (38.03%), major public sentiment (37.86%), public health events (37.37%) and policy changes (37.24%). The results of risk matrix and Borda count revealed 1 extremely high-risk indicator as information system emergency, 5 high-risk indicators with the highest risk being major public sentiment, 11 medium-risk indicators with the highest risk being major medical disputes and 1 low-risk indicator as external fires. Conclusion Conducting HVA in combination with the actual situation of blood banks can effectively identify high-risk events and provide theoretical basis for improving emergency management measures.

BackgroundMetacognition， the capacity to monitor and control one's cognitive processes， has been identified as a crucial component of effective decision-making and behavioral adaptation. Previous research has revealed cognitive deficits in patients with major depressive disorder （MDD）， while findings about metacognitive capacities in patients with MDD have been inconsistent across studies， and the exact relationship between metacognitive capacities and clinical symptoms in MDD patients remains uncertain.ObjectiveTo examine the metacognitive capacities of adolescent hospitalized patients with MDD and to explore its relationship with depressive and anxiety symptoms， thus providing an unprecedented insight into the prevention of MDD.MethodsA coherent 56 adolescent hospitalized patients with MDD in the Psychiatry Department at the Affiliated Hospital of Southwest Medical University from March 2022 to June 2023 and met the diagnostic criteria for depression as defined by the Diagnostic and Statistical Manual of Mental Disorders， fourth edition （DSM-IV） were enrolled as MDD group. At the same time， 62 healthy individuals matched with the age and sex of the MDD group residing in Luzhou were concurrently selected as control group. The metacognitive ability of the two groups was evaluated by perceptual decision-making task and confidence rating task， and the indicators included confidence deviation， reaction time of confidence evaluation and metacognitive efficiency. Additionally， the severity of depressive and anxiety symptoms was measured with Beck Depression Inventory （BDI） and Beck Anxiety Inventory （BAI）. Pearson correlation analysis was utilized to examine the relationship between metacognitive capacities and clinical symptoms.ResultsMDD group scored higher on BDI and BAI when compared with control group （t=-13.722， -9.674， P0.05）. In terms of metacognitive performance， MDD group reported a reduction in overall confidence， confidence in correct decisions， confidence in incorrect decisions and metacognitive efficiency compared with control group （t=3.044， 2.769， 2.836， 3.667， P0.05）. Furthermore， metacognitive efficiency in MDD patients exhibited negative correlation with both BDI and BAI scores （r=-0.269， -0.290， P

Sweetpotato is a heliophile crop. However, it is usually shaded in the lower position in the interplanting cultivation mode. During the middle and late field growing period, it often faces rainy weather with little illumination, which affects the dry matter accumulation in tuberous roots. Thus, analyzing the metabolic response pathways of sweetpotato under shade stress will provide the theoretical basis for the varieties' genetic improvement of shade tolerance. In this study, the sweetpotato variety Zhenghong 23 was exposed to shade stress with 50% light transmittance for 15 days. Results showed that chlorophyll b and the total chlorophyll contents of Zhenghong 23 under shade stress were significantly increased compared with those under natural light. The maximum photochemical efficiency (Fv/Fm), the potential activity (Fv/Fo), and the comprehensive index of photosynthetic performance (PIABS) of the chlorophyll photosystem PSII decreased significantly under shade stress. The net photosynthetic rate and water use efficiency decreased significantly, while SOD and POD enzyme activities increased significantly. In addition, shade stress increased significantly the vine length and specific leaf area of Zhenghong 23, but reduced significantly the fresh weight of roots. Transcriptome and metabolome analysis of leaf tissues under shade stress and natural light conditions showed that the DEGs and DMs were mainly enriched in phenylpropanoid biosynthesis, sugar metabolism, sphinolipid metabolism, and arginine biosynthesis pathways. Most of the up-regulated DEGs enriched in the phenylpropanoid biosynthesis pathway were POD enzyme family genes, indicating that the shade stress triggered the ROS scavenging system in sweetpotato. Meanwhile, shade stress reduced sugar metabolism level of sweetpotato, decreased the soluble sugar content of leaves, inhibited both the synthesis and degradation of starch, and blocked the expansion of tuberous roots. In addition, the sphinolipid and arginine metabolism pathways may better adapt sweetptoato plants to shade stress through improving the stability of biomembranes and increase the synthetic substrates of polyamine anti-stress factors. These results provide new theoretical basis for understanding the metabolic response pathways of sweetpotato under shade stress. [ABSTRACT FROM AUTHOR]

In order to recover user’s queries in conjunctive keyword searchable encryption schemes, two attacks against the conjunctive keyword searchable encryption schemes were proposed, such as cross leakage attack and frequency matching attack. Firstly, a set of candidate keywords were extracted from the leakage. Then the keywords were filtered according to the keyword pair result pattern leakage and query frequency information respectively. Results show that in the cross leakage attack, with knowledge of only 10% of the dataset, the accuracy of query recovery can reach up to 90% if the keyword space is 100. And more than 50% of the queries are still able to recovered by the attacker if the keyword space is expanded to 1 000. In frequency matching attack, even with only inaccurate frequency distribution information known to the attacker, at least 70% of queries can be accurately recovered.

The stability of compressor operation has an inducing and amplifying effect on the stability and performance of the entire engine. Therefore, it is required that the flow margin of the compressor should be wider to adapt to the working stability of the engine under variable operating conditions. A new blade structure with micro pits distributed on the suction surface of the mainstream blade is proposed based on "Golf ball effect". The flow of a certain type of centrifugal compressor impeller is numerically simulated by using the CFX fluid dynamics software to study the effect of adding micro pits on the performance of flow separation structure and flow margin at different parts of the suction surface of the blade. Study the effect of adding micro pit structures with radii of 0.25~0.30 mm at different parts of the blade suction surface on structural performance and flow margin. The results show that adding micro pits at the leading and trailing edges of the mainstream blade suction surface can improve the flow margin. When the radius of the micro pits is 0.3 mm, the flow margin effect is the best, which are increased by 3.01% and 3.15% respectively. The use of new structural blades can increase the compressor flow margin, and provide a reference for the design of centrifugal compressor impellers.

[Objective] Wind-water erosion crisscross region in Loess Plateau is a typical fragile ecosystem. Biological soil crusts (BSCs) are widely distributed in this region and play key roles in the accumulation and transformation of soil organic carbon (SOC). However, the effect of BSCs succession and microorganisms on enzymes related to organic carbon conversion is still unclear. [Methods] In this manuscript, SOC contents, microbial number and enzymes related with carbon conversion in different BSCs types were investigated. The relationships among SOC, microbial number and enzume activities related with carbon conversion were also analyzed by SEM model. [Results] (1) BSCs succession significantly inceased SOC content and enzyme activities related with carbon conversion. SOC and enzyme activities in BSCs layer(0—2 cm) were significantly higher than those in bare sand 2—5 cm soil layer (p

Hybrid DC transmission systems are prone to DC current oscillations as the parameters of constant DC current controller increase， an oscillation suppression strategy based on virtual resistance is proposed. This strategy generates an additional voltage that is in phase opposition to the disturbance component by leveraging the current oscillation component and an introduced virtual resistance， thereby achieving suppression of the DC current oscillations. Initially， a small-signal model of the hybrid DC transmission system is established to analyze the impact of parameters of the constant DC current controller on the stability of small signals. Subsequently， an oscillation suppression strategy based on virtual resistance is put forward to study the influence of virtual resistance on the stability of small signals in the system. The effectiveness of the proposed strategy is verified through PSCAD/EMTDC simulations. Lastly， the stability range of the virtual resistance under different constant current controller parameters is analyzed. The research findings indicate that the proposed control strategy can effectively eradicate DC current oscillations and improve system stability.