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The excitation function of the charged particle-induced reaction plays an important role in basic nuclear physics research, nuclear engineering design and nuclear technology applications, and which is also essential input information required in areas such as accelerator shielding and fusion reactor design, space radiation effects, radiation therapy and biomedical radioisotope production. In the field of tumor therapy, 211At is ideal targeted therapeutic nuclide for generating α-rays, which is prepared by α-particle bombardment of a bismuth target, and therefore the large-scale production of 211At nuclide relies on the information related to the data of 209Bi(α,2n)211At reaction excitation function and the thick target yield of the 211At nuclide. The production of 211At nuclide is accompanied with the production of 210At nuclide (the decaying substrates are highly toxic 210Po nuclides), and it is also necessary to analyze the data of excitation function for the 209Bi(α,3n)210At reaction and the thick target yield of the 210At nuclide for determining whether the prepared 211At product meets the requirements of the subsequent drug labelling. Based on the above background, the experimental data of 209Bi(α,2n)211At and 209Bi(α,3n)210At reaction excitation function in the Experimental Nuclear Reaction Database (EXFOR) were compiled and analyzed. However, there are still divergency in the experimental data of the reaction excitation functions, especially for the 209Bi(α,3n)210At reaction, and the analyzed available experimental data are discontinuous in some energy region. For providing the reasonable and continuous data of the above two reactions, the relevant theoretical calculations were carried out based on the EMPIRE code. Through the comparison between the experimental data and the EMPIRE calculation results, the reasonable forms of optical potential parameters and level density parameters are chosen. With the enhanced generalized superuid model (EGSM) for level density in the EMPIRE code, the evolution data of the excitation functions of the above two reactions are obtained, and both of them are in general agreement with the analyzed experimental data. Based on the evolution data of 209Bi(α,2n)211At reaction excitation function, the thick target yield of the medical radioisotope 211At was calculated, and it is in good agreement with the related experimental data. Besides, the thick target yield of 210At (the parent nucleus of the highly toxic nuclide 210Po) was also studied. And the results show that the thick target yield ratio of 210At to 211At is less than 10-5 at Eα

Under the carbon trading mechanism, virtual power plants (VPP) aggregating distributed energy resource (DER) to participate in electricity market (EM) trading will help new energy consumption and improve environmental benefits. This paper constructed a multi-agent VPP model including wind turbine, photovoltaic power, controllable distribution generation, stored energy, and flexible load, and formulated bidding strategies for each entity participating in the electric energy market (EEM) and peak regulating market (PRM). The EEM and PRM examples showed that participating in peak regulating bidding by VPP could achieve the maximum benefits of VPP and reasonable distribution of the interests among DER members. Moreover, this paper introduced the carbon trading mechanism, analyzed the correlation between changes in carbon trading price and wind and solar consumption rate, carbon emissions and VPP benefits, and further explored the impact of carbon sink resource trading on electricity price, output and energy demand change rate. It provided a basis for the ecological protection compensation mechanism of carbon sink value, and also provided a reference for the price transmission effect of carbon market (CM) on EM under the coordination of electricity-carbon market and the optimization design of CM price mechanism.

The research progress of the compressive permanent deformation of silicone rubber was reviewed, and the influences of base rubber, filler, auxiliary agent, sample size and testing environment on the compressive permanent deformation were introduced. The research direction of low compression permanent deformation of silicone rubber was also prospected. [ABSTRACT FROM AUTHOR]

The research progress of oil-resistant silicone rubber was reviewed, and three main methods to improve the oil resistance of silicone rubber were introduced, which were adjusting the formula, introducing polar functional groups, and blending with other rubber. The application prospect of oil-resistant silicone rubber was also speculated. [ABSTRACT FROM AUTHOR]

Production technology of chenille union fabric was studied. A chenille union fabric was taken as an example, fabric specifications were introduced. In order to ensure successful production, comparative tests were carried out on heald type, healding, reeding and droper threading method. Warp stop per 100 000 wefts was used as evaluation index, orthogonal test of loom process was carried out. The results showed that using the optimized process, the average loom speed was reached 426 r/min, the average loom efficiency was above 85.10% and the finished product weaving defect rate was controlled within 0.5%. It is considered that optimizing special parts and loom process are the keys to ensuring successful production. [ABSTRACT FROM AUTHOR]

There are a large number of Late Paleozoic volcanic rocks existing in Karamaili area, recording the activities of the Siberia plate and the Kazakhstan-Junggar plate. This paper systematically analyzes the lithofacics and geochemical characteristics of the basic volcanic rocks in Shuangquan gold mine of Karamaili, and discusses the geotectonic environment and its significance. The basic volcanic rocks of Shuangquan gold mine belong to the peraluminous and calc-alkaline rock series, and the rocks are rich in potassium and magnesium and are poor in sodium and calcium. The magmatic hydrothermal source may be the crust and mantle mixed magma of the lower crust or upper mantle. At the same time, the abundance of large ion lithophile elements is low, enriching light rare earth elements, and significantly depleting high field strength elements, showing the rock characteristics of the continental and oceanic plates in which island are volcanic rocks and crust are assimilated. The characteristics of the island arc volcanic rocks are shown on the environmental structure discriminant diagram. It is speculated that it is likely to he formed in the fore-arc tension environment affected by the oceanic ridge subduction. [ABSTRACT FROM AUTHOR]

Heat-resistant and salt-tolerant acrylamide copolymer is one of the hotspots in the current research, which is formed of acrylamide as main monomer, added the monomer with properties of heat-resistant and salt-tolerant. This article introduces the heat-resistant and satt-tolerance mechanism of function monomer, polymerization method, and the choice of initiator. Through the recent research status of heat-resistant and satt-tolerant acrylamide based copolymers at home and abroad, adding adequate function monomer is the most effective way to improve the heat-resistant and salt-tolerance of polyacrylamide. And selecting the appropriate polymerization method and initiator could obversly influence the molecular weight and performance of copolymer. [ABSTRACT FROM AUTHOR]

Study on formation process of biological purification efficiency in raw watei delivery pipelines was beneficial to improve water quality in long distance raw water delivery pipes. Using simulated pipeline reactors to simulate water situation in raw water delivery pipelines, and water samples were prepared in laboratory. The influent and effluent water quality, the microorganisms in the biofilm is continuously monitored. Results show that the ammonia nitrogen (NH4+-N) and organic matter removal are stabilized after a gradual increase in first, and stable value decreases slightly compared to the maximum in the formation process of biological purification efficiency. Biofilm grow on polyethylene slides in simulated pipeline reactor and then harvest within 45 days, the removal rate of NH4+ - N remains stable at 75%. Nitrite nitrogen ( NO2- - N ) effluent concentration remains stable at 0.02 mg/L. Ammonia oxidizing bacteria (AOB) is dominant stiain compared to nitrite oxidizing bacteria (NOB) in raw water delivery pipes. Removal rate of UV254 and turbidity are about 30%, and orthophosphate (PO43-) removal rate ranges from 13. 64% to 38. 78%. [ABSTRACT FROM AUTHOR]

The combination of chlorine dioxide (ClO2) and chlorine (NaOCl) or monochloramine (NH2Cl) was used to degrade the formation of ClO2-, when ClO2 was used as an effective oxidant which could form undesirable oxidation by-products, i.e. ClO2-. In this article, Mill-Q water was used, and the impact of NaOCl or NH2Cl combined with ClO2 or ClO2 on the yield of ClO2 and ClO2 were investigated by monitoring the residual of NaOCl, NH2Cl, ClO2 and ClO2-. It was proved that when NaOCl or NH2Cl combined with ClO2, hypoehlorousacid (HOCl) formed by NaOCl or NH2Cl could react with ClO2-, which was the reason that ClO2 yield reduced and C102yield increased, and the increase in ClO2 yield exceeded the decrease in ClO2 yield. For the purpose of the highest reaction rate, the optimal ratio between NaOCl and ClO2 was 3:1, while it was 1:1 between NH2Cl and ClO2. The appropriate ratios of residual NaOCl/NH2Cl and ClO2 for ClO2 complete removal were found to be close to the value of 1 and 0.5 respectively. Furthermore, compared with NaOCl, equivalent yield of NH2Cl had much more ClO2 residual yield when reacted with ClO2, and had faster reaction rate in any ratio. It can be concluded that the generation of ClO2 is typically much lower and the residual of ClO2 is much higher with combination of ClO2 and NaOCl or NH2Cl when compared to the use of ClO2 alone. And the minimum ratio between NaOCl and ClO2, NH2Cl and CIO2 are 3:1 and 1:1 respectively when used in micro-polluted water. [ABSTRACT FROM AUTHOR]

Acupuncture manipulation, a crucial component of acupuncture procedures, significantly influences the therapeutic outcomes. Acupuncture manipulation measuring instrument and operating instrument have been developed based on modern technology to objectively characterize manipulation parameters, and achieve standardized and normalized output of acupuncture manipulation. This paper systematically reviews the development and current application status of in vivo acupuncture manipulation measuring instrument, ex vivo acupuncture manipulation measuring instrument, and acupuncture manipulation operating instrument worldwide, and explores key issues that acupuncture manipulation operating instruments need to address for clinical applications, and provides insights into the future prospect of acupuncture robots.

The biofilms formed by pathogenic microorganisms seriously threaten human health and significantly enhance drug resistance, which urgently call for developing drugs specifically targeting on biofilms. Chitooligosaccharides extracted from shrimp and crab shells are natural alkaline oligosaccharides with excellent antibacterial effects. Nevertheless, their inhibition efficacy on biofilms still needs to be improved. Spirulina (SP) is a microalga with negatively charged surface, and its spiral structure facilitates colonization in the depth of the biofilm. Therefore, the complex of Spirulina and chitooligosaccharides may play a synergistic role in killing pathogens in the depth of biofilm. This research first screened chitooligosaccharides with significant bactericidal effects. Subsequently, Spirulina @Chitooligosaccharides (SP@COS complex was prepared by combining chitooligosaccharides with Spirulina through electrostatic adsorption. The binding of the complex was characterized by zeta potential, z-average size, and fluorescence labeling. Ultraviolet-visible spectroscopy (UV-Vis) showed the encapsulation efficiency and the drug loading efficiency reached up to 90% and 16%, respectively. The prepared SP@COS2 exhibited a profound synergistic inhibition effect on bacterial and fungal biofilms, which was mainly achieved by destroying the cell structure of the biofilm. These results demonstrate the potential of Spirulina -chitooligosaccharides complex as a biofilm inhibitor and provide a new idea for addressing the harm of pathogenic microorganisms.

Objective: To study the effects of trioxygen pretreatment on cerebral ischemia/reperfusion (I/R) injury in rats., Methods: A total of 24 clean grade male Sprague-Dawley (SD) rats were randomly divided into Sham group, brain I/R group (I/R group) and Ozone pretreatment group (Ozone group), with 8 rats in each group. The animals were routinely fed, and the operation was performed 5 days after the intervention of Ozone group by intraperitoneal injection of trioxygen water (concentration 80 mg/L, 0.01 mL/g), and the Sham group and I/R group were injected with equal volume normal saline. The Sham group only separated the arteries without ligation, and the I/R group and Ozone group established the rat cerebral I/R model. Neurological deficit score (NDS) was performed 2 hours after ischemia and modified neurological deficit score (mNSS) was performed 24 hours after reperfusion. Brain tissue was collected after anesthesia. Cerebral infarction was observed by 2, 3, 5-triphenyltetrazolium chloride (TTC) staining and the percentage of cerebral infarction volume was calculated. Protein expression of metabolic glutamate receptor 5 (mGluR5) and ionic glutamate α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor (AMPAR) subunit GluA2 in cerebral ischemic penumbra was determined by Western blotting., Results: Compared with the Sham group, NDS score, mNSS score and percentage of cerebral infarction volume in I/R group were increased [NDS score: 2.63±0.52 vs. 0, mNSS score: 9.63±1.19 vs. 1.13±0.64, cerebral infarction volume: (41.25±2.93)% vs. 0%, all P < 0.05], and expressions of mGluR5 and GluA2 in penumbra area of cerebral ischemia were decreased [mGluR5 protein (mGluR5/β-actin): 0.44±0.14 vs. 1.00±0.10, GluA2 protein (GluA2/β-actin): 0.23±0.08 vs. 1.00±0.25, both P < 0.05]. Compared with the I/R group, mNSS score and percentage of cerebral infarction volume in the Ozone group were decreased [mNSS score: 7.00±1.20 vs. 9.63±1.19, cerebral infarction volume: (27.23±6.21)% vs. (41.25±2.93)%, both P < 0.05], and mGluR5 and GluA2 expressions in the penumbra of cerebral ischemia were up-regulated [mGluR5 protein (mGluR5/β-actin): 0.81±0.10 vs. 0.44±0.14, GluA2 protein (GluA2/β-actin): 0.76±0.13 vs. 0.23±0.08, both P < 0.05]., Conclusions: Trioxygen preconditioning can alleviate cerebral I/R injury in rats, and its mechanism may be related to the upregulation of GluR5 and GluA2 in the ischemic penumbra.

Medical magnetic nanoparticles are nano-medical materials with superparamagnetism, which can be collected in the tumor tissue through blood circulation, and magnetic particle imaging technology can be used to visualize the concentration of magnetic nanoparticles in the living body to achieve the purpose of tumor imaging. Based on the nonlinear magnetization characteristics of magnetic particles and the frequency characteristics of their magnetization, a differential detection method for the third harmonic of magnetic particle detection signals is proposed. It was modeled and analyzed, to study the nonlinear magnetization response characteristics of magnetic particles under alternating field, and the spectral characteristics of magnetic particle signals. At the same time, the relationship between each harmonic and the amount of medical magnetic nanoparticle samples was studied. On this basis, a signal detection experimental system was built to analyze the spectral characteristics and power spectral density of the detected signal, and to study the relationship between the signal and the excitation frequency. The signal detection experiment was carried out by the above method. The experimental results showed that under the alternating excitation field, the medical magnetic nanoparticles would generate a spike signal higher than the background sensing signal, and the magnetic particle signal existed in the odd harmonics of the detected signal spectrum. And the spectral energy was concentrated at the third harmonic, that is, the third harmonic magnetic particle signal detection that meets the medical detection requirement could be realized. In addition, the relationship between each harmonic and the particle sample volume had a positive growth relationship, and the detected medical magnetic nanoparticle sample volume could be determined according to the relationship. At the same time, the selection of the excitation frequency was limited by the sensitivity of the system, and the detection peak of the third harmonic of the detection signal was reached at the excitation frequency of 1 kHz. It provides theoretical and technical support for the detection of medical magnetic nanoparticle imaging signals in magnetic particle imaging research.

Objective: To investigate the application value of contrast-enhanced ultrasound (CEUS) technique to assist the repair of oral and maxillofacial defects by superficial inferior epigastric artery perforator flap., Methods: Sixteen oral cancer patients, 10 males and 6 females, who were to undergo superficial inferior epigastric artery perforator flap repair between June 2018 and February 2020, were selected, with an average age of 55.8 years (range, 24-77 years). There were 13 cases of squamous cell carcinoma, 2 cases of adenoid cystic carcinoma, and 1 case of mucinous epidermis-like carcinoma. The color Doppler ultrasound (CDUS) and CEUS were used to screen the superficial inferior epigastric artery, assisted in the design of the flap, and compared it with the actual intraoperative exploration. The sensitivity, specificity, positive predictive value, and negative predictive value of CEUS and CDUS examinations were analyzed. Fourteen of 16 patients were repaired with superficial inferior epigastric artery perforator flap, and 2 patients were repaired with superficial iliac artery flap because the source artery was not found. After surgery, regular follow-up was performed to check for disease recurrence and metastasis and to evaluate the appearance of the patien's donor area, the recovery of transoral feeding function, and the presence of complications., Results: Comparison of preoperative CDUS and CEUS findings and intraoperative exploration showed that CEUS had 100% sensitivity, specificity, positive predictive value, and negative predictive value for vascular exploration of the superficial inferior epigastric artery perforator flap, compared with 57%, 100%, 100%, and 25% for CDUS. The preoperative CDUS identified 25 penetrating vessels in 14 cases repaired with superficial inferior epigastric artery flaps. All vessel signals were enhanced by CEUS enhancement, and an additional 11 penetrating vessels were identified confirmed intraoperatively. The preoperative CEUS measurements of the initial diameter of superficial arteries in the abdominal wall were significantly higher than both CDUS and intraoperative measurements ( P <0.05); the difference in peak systolic velocity between CEUS and CDUS measurements was significant ( t =3.708, P =0.003). One case of superficial epigastric artery perforator flap developed venous embolism crisis at 48 hours after operation, the wound healing delayed. The other incisions in donor sites healed by first intention. All the patients were followed up 3-12 months, with an average of 8 months. No recurrence or metastasis appeared during the follow-up. There was no serious complications such as abdominal wall hernia, the location of abdominal scarring was hidden, and transoral feeding was resumed., Conclusion: The superficial inferior epigastric artery perforator flap with small injury in supply area and hidden scar location is a better choice for repairing oral and maxillofacial defects. The use of CEUS technique to assist the preoperative design of the superficial inferior epigastric artery perforator flap has good feasibility and high accuracy.

Objective: Feature extraction of breast tumors is very important in the breast tumor detection (benign and malignant) in ultrasound image. The traditional quantitative description of breast tumors has some shortcomings, such as inaccuracy. A simple and accurate feature extraction method has been studied., Methods: In this paper, a new method of boundary feature extraction was proposed. Firstly, the shape histogram of ultrasound breast tumors was constructed. Secondly, the relevant boundary feature factors were calculated from a local point of view, including sum of maximum curvature, sum of maximum curvature and peak, sum of maximum curvature and standard deviation. Based on the boundary features, shape features and texture features, the linear support vector machine classifiers for benign and malignant breast tumor recognition was constructed., Results: The accuracy of boundary features in the benign and malignant breast tumors classification was 82.69%. The accuracy of shape features was 73.08%. The accuracy of texture features was 63.46%. The classification accuracy of the three fusion features was 86.54%., Conclusions: The classification accuracy of boundary features was higher than that of texture features and shape features. The classification method based on multi-features has the highest accuracy and it describes the benign and malignant tumors from different angles. The research results have practical value.

The determination of ambient carbonyls by the derivative method inevitably leads to the introduction of extra 2,4-dinitrophenylhydrazine (2,4-DNPH) into the sample solution. Traditional solid phase extraction (SPE) materials cannot remove this interference. To address this issue, a selective molecularly imprinted solid phase extraction (MISPE) column was prepared. With 2,4-dinitroaniline (2,4-DNAN) as the dummy template, MISPE could eliminate the excessive derivative agent (2,4-DNPH) in the air samples. Consequently, the sample could be concentrated effectively while the sensitivity increased greatly. By coupling MISPE and high performance liquid chromatography (HPLC), the developed method was used to study the concentration and source of 14 carbonyls of PM2.5 during spring in Guangzhou Higher Education Mega Center. Results showed that the total concentration of carbonyls increased with the level of air pollution. Particularly, the content of isovaleraldehyde increased sharply to account for 21% of the 14 total carbonyls in the haze days. Moreover, a high positive correlation between isovaleraldehyde and propionaldehyde was found either in normal days or haze days. From the correlation analysis, it was shown that anthropogenic emissions together with photochemical reaction had contributed to the abnormally high levels of carbonyls in ambient PM2.5 in the haze days. This aspect should be further investigated.

Professor GUO Yi learnt from several famous acupuncturists and develops his own manipulations based on his teachers' clinical thoughts and family manipulations. " Kongque Kaiping " is for cervical spondylosis and cerebrovascular diseases, etc, the description including Fengfu (GV 16), Fengchi (GB 20), Tianzhu (BL 10), Yifeng (TE 17) and Wangu (GB 12). " Qianlong Ruhai " is for the syndromes of hyperactivity of liver yang , upper heat and lower cold, and the acupoints are Taichong (LR 3), Xiangu (ST 43), Xiaxi (GB 43) and the point in the dorso-ventral boundary after fingerweb edge between the 3rd and 4th toes. " Shanyang Hupiao " can improve local loop and pharyngeal function with Lianquan (CV 23) and Panglianquan (Extra), 1 cun besides Lianquan (CV 23). The traditional manipulations of " Laolv Lamo " is for stomach and abdomen diseases with Zhongwan (CV 12) and Xiawan (CV 10) in abdomen, and professor GUO Yi believes that it can treat mental illness which is the same treatment for different diseases.

Accurate placement of pedicle screws is a key factor of spinal surgery. Investigation of a new real-time intra-operative monitoring method is an important area of clinical application research which makes a contribution to planting pedicle screw accurately. Porcine spines were chosen as experimental objects. The changes of reduced scattering coefficient (μ'(s)) along normal puncture path, medial perforation path and lateral perforation path were measured and studied. A conclusion is drawn that there are two distinct peaks throughout the puncture process, appearing at the junction of cancellous bone and cortical bone, at the beginning and at the end, respectively. The reduced scattering coefficient is proved to be a good monitoring factor which can identify whether the screw is about to reach the critical position of the spine puncture. Moreover, the variation provides an important reference for spinal surgical navigation process.

Objective: To prepare monoclonal antibodies (mAbs) against S100A9, and characterize these antibodies' properties for functional studies., Methods: We amplified cDNA fragment of S100A9 from adult human liver sample, then constructed the vectors pGEX-4T-1-S100A9 and pET-32a-S100A9 for protein expression. The S100A9 protein fused respectively with the His-tag and GST-tag were expressed in E.coli and purified for immunizing mice as antigen and hybridoma screening, respectively. After hybriodma screening, the titer of mAbs was determined by ELISA and the specificity was identified by Western blotting and indirect immunofluorescence technique., Results: Both GST-tagged and His-tagged S100A9 fusion proteins were successfully constructed and expressed in E.coli. Eighteen hybridoma cell strains secreting S100A9 mAbs were obtained, of which 15 showed strong positive reaction but 3 showed weak positive reaction to the recombinant protein in Western blotting. Two hybridoma cell strains were capable of binding to S100A9 native protein in tumor tissue interstitial fluid., Conclusion: We successfully prepared the mAbs against S100A9 protein, which provide the useful tool for further study on biological function and clinical detection of S100A9.

Objective: To identify a non-enterotoxigenic strain of Bacteroides fragilis., Methods: B. fragilis was isolated from the feces of a healthy full-term infant in July 2012 and identified by morphological characteristics and culture conditions, physiological and biochemical test, drug sensitivity test, 16 s rRNA gene sequencing and short and long-term toxicity tests., Results: The isolated bacterial strain was similar to B. fragilis in terms of morphological characteristics, culture conditions and physiological and biochemical features. The results of 16s rRNA gene sequencing demonstrated that the nucleoids of newly-isolated strain were up to 99% identical to those of standard stain of B. fragilis NCTC9343 (GenBank). The drug sensitivity test revealed that it was not sensitive to cefradine, amoxicillin, gentamicin, sulfamethoxazole and trimethoprim. And the acute and long-term toxicity tests were negative., Conclusion: The isolated bacteria is a non-enterotoxigenic strain of B. fragilis.

Background and Objective: Bufalin, a component of the Chinese medicine chan'su, induces apoptosis in various human tumor cell lines. The aim of this study is to investigate the mechanism of anti-proliferation and the induction of apoptosis of Bufalin on non-small cell lung cancer cell., Methods: The effect of Bufalin on A549 cell proliferation was measured using MTT assay; the morphological change was observed with Wright-Giemsa stain; cell cycle phase distribution and hypodiploid DNA were determined by flow cytometry with PI; expressions of Livin, Caspase-3 were detected by Western blot., Results: MTT assay showed that Bufalin inhibited A549 cell proliferation in time and dose-dependent manner. The inhibition concentration of 50% cell growth (IC50) at 48 h, 72 h and 96 h were (56.14+/-6.72) nmol/L, (15.57+/-4.28) nmol/L and (7.39+/-4.16) nmol/L, respectively; apoptosis of A549 cells could be effectively induced by Bufalin; apoptotic bodies and sub-G1 peak (representing apoptosis) emerged when cells were treated with different concentrations, compared with the untreated control group (P < 0.01). The expression of Livin protein was downregulated (P < 0.01) and Caspase-3 protein was activated during Bufalin-induced apoptosis in A549 cells., Conclusions: Bufalin suppresses the growth of A549 cells and induces apoptosis; inhibition of Livin and activation of Caspase-3 may be involved in its mechanism.