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Development of nonprecious metal-based single-atom catalysts (SACs) has provided opportunities to substitute Pt group metals and offer maximum atom utilization and unique coordination environments. Among these catalysts, Fe-N-C catalysts with atomically dispersed Fe-N4 active sites have emerged as some of the most promising oxygen reduction reaction (ORR) catalysts. However, furnace synthesis of Fe-N-C catalysts with carbon substrate derived from metal-organic framework (MOF) involves a high-temperature procedure, in which nitrogen from the carbonized MOF tends to be removed, subsequently leading to a low density of active sites. In this work, we developed a rapid and simple solid-state route to fabricate SACs through laser-induced thermal activation (LITA) of carbonized zeolitic imidazolate framework-8 (ZIF-8) adsorbed with Fe precursors. The results demonstrate that the laser process effectively avoids the loss of nitrogen in the nitrogen-doped carbon substrate and achieves a loading of Fe single atoms of 2.3 wt %, in comparison with that of 1.2 wt % from the conventional furnace treatment. The Fe-N-C catalyst synthesized in the study presents a half-wave potential of 0.91 V for ORR in alkaline media, which is higher than that of commercial Pt/C (0.87 V). When used as a cathode catalyst in zinc-air batteries (ZABs), the battery exhibits excellent electrochemical performance. This work also demonstrates the versatility of the technique through the successful synthesis of Co-N-C and Ni-N-C single atoms on nitrogen-doped carbon substrates.

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@# Objective    To explore the predictive value of a simplified signs scoring system for the severity and prognosis of patients with coronavirus disease 2019 (COVID-19). Methods     Clinical data of 1 605 confirmed patients with COVID-19 from January to May 2020 in 45 hospitals of Sichuan and Hubei Provinces were retrospectively analyzed. The patients were divided into a mild group (n=1 150, 508 males, average age of 51.32±16.26 years) and a severe group (n=455, 248 males, average age of 57.63±16.16 years). Results    Age, male proportion, respiratory rate, systolic blood pressure and mean arterial pressure in the severe group were higher than those in the mild group (P<0.05). Peripheral oxygen saturation (SpO2) and Glasgow coma scale (GCS) were lower than those in the mild group (P<0.05). Multivariate logistic regression analysis showed that age, respiratory rate, SpO2, and GCS were independent risk factors for severe patients with COVID-19. Based on the above indicators, the receiver operating characteristic (ROC) curve analysis showed that the area under the curve of the simplified signs scoring system for predicting severe patients was 0.822, which was higher than that of the quick sequential organ failure assessment (qSOFA) score and modified early warning score (MEWS, 0.629 and 0.631, P<0.001). The ROC analysis showed that the area under the curve of the simplified signs scoring system for predicting death was 0.796, higher than that of qSOFA score and MEWS score (0.710 and 0.706, P<0.001). Conclusion    Age, respiratory rate, SpO2 and GCS are independent risk factors for severe patients with COVID-19. The simplified signs scoring system based on these four indicators may be used to predict patient's risk of severe illness or early death.

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Objective:To analyze the risk factors of lower extremities deep vein thrombosis after thoracoscopic surgery in elderly patients with lung cancer, establish a nomogram prediction model and conduct internal verification.Methods:A total of 183 elderly patients with lung cancer who underwent thoracoscopic radical resection in Nanchong Central Hospital from February 2018 to February 2022 were selected as the study subjects. According to the presence or absence of deep venous thrombosis of the lower extremities within one month after operation, the patients were divided into lower extremities deep venous thrombosis group ( n=61) and non-deep lower extremities venous thrombosis group ( n=122) . Univariate and multivariate analyses of deep venous thrombosis of lower extremities after thoracoscopic surgery for lung cancer in the elderly were performed, and a nomogram prediction model was constructed according to the multivariate analysis results, and the model was verified. Results:There were statistically significant differences in smoking history ( χ2=13.40, P<0.001) , preoperative chemotherapy ( χ2=8.79, P=0.003) , surgical method ( χ2=7.97, P=0.005) , operation time ( t=7.23, P<0.001) , postoperative bed rest time ( t=10.40, P<0.001) , combined with diabetes ( χ2=6.37, P=0.012) , combined with hyperlipidemia ( χ2=9.58, P=0.002) , preoperative D-dimer ( t=13.08, P<0.001) , preoperative fibrinogen ( t=5.84, P<0.001) and preoperative platelet count ( t=7.01, P<0.001) between the lower extremity deep venous thrombosis group and the non-lower extremity deep venous thrombosis group. The results of multivariate logistic regression analysis showed that preoperative chemotherapy ( OR=2.45, 95% CI: 1.05-5.71, P=0.038) , surgical method ( OR=2.55, 95% CI: 1.14-5.73, P=0.023) , postoperative bed rest time ( OR=1.50, 95% CI: 1.24-1.81, P<0.001) , combined with diabetes ( OR=3.60, 95% CI: 1.05-12.33, P=0.042) , and preoperative D-dimer ( OR=1.01, 95% CI: 1.01-1.01, P<0.001) were all independent risk factors for lower extremity deep vein thrombosis in elderly patients with lung cancer after thoracoscopic surgery. The C-index of nomogram for predicting lower extremity deep vein thrombosis-related factors was 0.86 (95% CI: 0.81-0.93) . The calibration curve showed that the model had a good correlation in predicting lower extremities deep venous thrombosis. Conclusion:Preoperative chemotherapy, surgical method, postoperative bed rest time, combined with diabetes, and postoperative D-dimer level are influence factors for lower extremity deep vein thrombosis in elderly patients with lung cancer after thoracoscopic surgery. The nomogram prediction model established in this study has high accuracy and discrimination for the prediction of lower extremity deep vein thrombosis in elderly patients with lung cancer after thoracoscopic surgery.

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OBJECTIVE@#To evaluate the existing randomized controlled trials (RCTs) for evidence of the efficacy and safety of head acupuncture (HA) plus Schuell's language rehabilitation (SLR) in post-stroke aphasia.@*METHODS@#Seven databases including Embase, PubMed, Cochrane Library, Technology Periodical Database, the China National Knowledge Infrastructure, SinoMed and Wanfang Data Information Site were searched for RCTs published from database inception until November 14, 2021. RCTs that compared HA plus SLR with sham (or blank) control, acupuncture therapy alone, certain language rehabilitation therapy alone or other therapies for post-stroke aphasia were included. Data were extracted and assessed, and the quality of RCTs was evaluated. Fixed-effects model was used, with meta-inflfluence analysis, meta-regression, and regression-based sub-group analyses applied for exploration of heterogeneity. Publication bias was estimated by funnel plots and Egger's tests.@*RESULTS@#A total of 32 RCTs with 1,968 patients were included and 51 comparisons were conducted classified as types of strokes and aphasia. (1) For patients with aphasia after ischemic stroke, HA plus PSA showed significantly higher accumulative markedly effective rate [relative risk (RR)=1.55, 95% confidence interval (CI): 1.19-2.02, I2=0%] and accumulative effective rate (RR=1.22, 95% CI: 1.09-1.36, I2=0%). (2) For patients with comprehensive types of stroke, HA plus PSA was more effective in increasing recovery rate (RR=1.89, 95% CI: 1.39-2.56, I2=0%), accumulative markedly effective rate (RR=1.53, 95% CI: 1.36-1.72, I2=9%) and accumulative effective rate (RR=1.14, 95% CI: 1.09-1.19, I2=34%). (3) For patients with aphasia after stroke, HA plus PSA was superior to PSA alone with statistical significance in increasing recovery rate (RR=2.08, 95% CI: 1.24-3.46, I2=0%), accumulative markedly effective rate (RR=1.49, 95% CI: 1.24-1.78, I2=0%) and accumulative effective rate (RR=1.15, 95% CI: 1.06-1.24, I2=39%). (4) For patients with multiple types of aphasia, HA plus PSA also demonstrated significantly higher recovery rate (RR=1.86, 95% CI: 1.28-2.72, I2=0%), accumulative markedly effective rate (RR=1.55, 95% CI: 1.35-1.78, I2=22%), and accumulative effective rate (RR=1.17, 95% CI: 1.11-1.23, I2=41%). (5) For patients with motor aphasia after ischemic stroke, compared with PSA alone, HA plus PSA showed significantly higher accumulative markedly effective rate (RR=1.38, 95% CI: 1.06-1.79, I2=0%) and accumulative effective rate (RR=1.20, 95% CI: 1.05-1.37, I2=0%). Meta-regression analyses were performed without significant difference, and publication bias was found in some comparisons.@*CONCLUSION@#HA plus SLR was significantly associated with better language ability and higher effective rate for patients with post-stroke aphasia, and HA should be operated cautiously especially during acupuncture at eye and neck. (Registration No. CRD42020154475).

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Objective To investigate whether Dajianzhong decoction can treat visceral pain of irritable bowel syndrome (IBS) by interfering with ERK1/2/nuclear factor kB (NF-kB) pathway and its downstream molecules.Methods The IBS visceral pain rat model was prepared by method such as mother-infant separation, acetic acid enema, and intraperitoneal injection of chicken ovalbumin. Rats were randomly divided into normal control group (normal saline), model group (normal saline), Dajianzhong decoction (10.8 g/kg) treatment group, and the control group of pinaverium bromide (45 mg/kg). Eight rats in each group were given intragastrically for 14 days. To evaluate the visceral sensitivity of rats, abdominal withdrawal reaction (AWR) was used ; the expression of ERK1/2 mRNA, NF-kB mRNA, cyclooxygenase-2 (COX-2)mRNA, and matrix metalloproteinase 9 (MMP-9) mRNA in colon tissue of rats in each group were detected by Real-time PCR; Immunohistochemistry staining method was used to detect the expression of NF-kB and COX-2 in the colon tissue of each group. Results Compared with the normal rats, AWR scores of model rats increased significantly at 60, 40 and 20 mmHg pressure (P0.05). Conclusion Dajianzhong decoction can play a role in treating visceral pain of irritable bowel syndrome ( IBS) by interfering ERK1/2/NF-kB pathway and its downstream molecules..

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Single-atom catalysts (SACs) with atomically dispersed catalytic sites have shown outstanding catalytic performance in a variety of reactions. However, the development of facile and high-yield techniques for the fabrication of SACs remains challenging. In this paper, we report a laser-induced solid-phase strategy for the synthesis of Pt SACs on graphene support. Simply by rapid laser scanning/irradiation of a freeze-dried electrochemical graphene oxide (EGO) film loaded with chloroplatinic acid (H2PtCl6), we enabled simultaneous pyrolysis of H2PtCl6 into SACs and reduction/graphitization of EGO into graphene. The rapid freezing of EGO hydrogel film infused with H2PtCl6 solution in liquid nitrogen and the subsequent ice sublimation by freeze-drying were essential to achieve the atomically dispersed Pt. Nanosecond pulsed infrared (IR; 1064 nm) and picosecond pulsed ultraviolet (UV; 355 nm) lasers were used to investigate the effects of laser wavelength and pulse duration on the SACs formation mechanism. The atomically dispersed Pt on graphene support exhibited a small overpotential of -42.3 mV at -10 mA cm-2 for hydrogen evolution reaction and a mass activity tenfold higher than that of the commercial Pt/C catalyst. This method is simple, fast and potentially versatile, and scalable for the mass production of SACs.

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Background: The abnormalities in brain function and structure of patients with functional constipation (FC) have been identified using multiple neuroimaging studies and have confirmed the abnormal processing of visceral sensation at the level of the central nervous system (CNS) as an important reason for FC. As an important basis for central information transfer, the role of the white matter (WM) networks in the pathophysiology of FC has not been investigated. This study aimed to explore the topological organization of WM networks in patients with FC and its correlation with clinical variables. Methods and Analysis: In this study, 70 patients with FC and 45 age- and gender-matched healthy subjects (HS) were recruited. Diffusion tensor imaging (DTI) data and clinical variables were acquired from each participant. WM networks were constructed using the deterministic fiber tracking approach, and the global and nodal properties of the WM networks were compared using graph theory analysis between patients with FC and HS. The relationship between the representative nodal characteristics-nodal betweenness and clinical parameters was assessed using partial correlation analysis. Results: Patients with FC showed increased nodal characteristics in the left superior frontal gyrus (orbital part), right middle frontal gyrus (orbital part), and right anterior cingulate and paracingulate (P < 0.05, corrected for false discovery rate) and decreased nodal characteristics in the left caudate and left thalamus (P < 0.05, corrected for false discovery rate) compared with HS. The duration of FC was negatively correlated with the nodal betweenness of the left thalamus (r = -0.354, P = 0.04, corrected for false discovery rate). Conclusion: The results indicated the alternations in WM networks of patients with FC and suggested the abnormal visceral sensation processing in the CNS from the perspective of large-scale brain WM network.

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OBJECTIVE@#To study the effect of calorie-enriched formula on postoperative catch-up growth in infants with cyanotic congenital heart disease (CHD).@*METHODS@#A total of 100 infants with cyanotic CHD who underwent surgical operation from January to December, 2017, were randomly divided into a high-calorie group (receiving calorie-enriched formula after surgery) and a conventional group (receiving standard formula after surgery), with 50 infants in each group. All infants were followed up for 6 months. The observation indices included body height, body weight, prealbumin, and N-terminal pro-brain natriuretic peptide before surgery, at the time of ventilator weaning and extubation after surgery, and at 1, 3, and 6 months after surgery. Height-for-age Z-score (HAZ), weight-for-age Z-score (WAZ), and weight-for-height Z-score (WHZ) were also assessed. Adverse reactions were recorded for both groups.@*RESULTS@#There were 25 cases (50%) and 21 cases (42%) of malnutrition in the high-calorie group and the conventional group respectively before surgery (@*CONCLUSIONS@#Compared with the standard formula, calorie-enriched formula can better help with postoperative catch-up growth in infants with cyanotic CHD.

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Objective:To investigate the effects of Da Jianzhongtang on substance P （SP）， mast cells （MC）， Toll like receptor 2 （TLR2）， TLR4 on MC model and nuclear transcription factor （NF）-<italic>κ</italic>B p65 in visceral pain rats with irritable bowel syndrome （IBS）， and explore its mechanism of action on IBS visceral pain. Method:Forty-eight 3-day-old SD rats were randomly divided into 6 groups： the control group （control）， irritable bowel syndrome group （IBS）， ketotifen group （Ketotifen，0.18 mg·kg^-1）， Da Jianzhongtang low， medium and high dose groups （DJZT-L， DJZT-M， DJZT-H，2.16，1.08，0.54 g·kg^-1）， with 8 rats in each group. Intragastric administration lasted for 2 weeks. Maternal separation method was used to establish the IBS visceral pain model in rats. The visceral sensitivity of rats was evaluated at 60， 40 and 20 mmHg （1 mmHg≈0.133 kPa） with Abdominal wall withdrawal response （AWR） scale. SP and NF-<italic>κ</italic>B p65 protein expression levels in colon tissue were detected with Western blotting technique. TLR2 and TLR4 proteins on mast cell membrane were detected by immunofluorescence staining. The degranulation rate of mast cells in colon tissue was detected by toluidine blue staining. Result:Compared with normal rats， AWR scores of model rats significantly increased at 60， 40， and 20 mmHg pressure （<italic>P</italic><0.05，<italic>P</italic><0.01）， the degranulation rate of mast cells in colon tissue and SP protein expression in colon tissue significantly increased （<italic>P</italic><0.01）， TLR2， TLR4， and nuclear NF-<italic>κ</italic>B p65 expression on mast cell membrane significantly increased （<italic>P</italic><0.01）. Compared with model rats， the AWR scores of DJZT-H group （pressure of 40， 20 mmHg） and DJZT-M group （pressure of 60， 40， 20 mmHg） significantly decreased. Meanwhile， the degranulation rate of colon mast cells， and the SP， TLR2， TLR4， and NF-<italic>κ</italic>B p65 expression also significantly decreased （<italic>P</italic><0.05，<italic>P</italic><0.01）. Conclusion:Da Jianzhongtang can affect mast cell activity and finally decrease visceral pain of IBS rats by down-regulating SP in colon tissue.

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The rapid development of artificial intelligence technology has achieved a breakthrough in many disciplines. Artificial intelligence has a far-reaching significance in promoting the further development of laboratory medicine. At present, artificial intelligence technology has gradually penetrated into all processes of laboratory work, such as laboratory data processing, laboratory data mining and laboratory quality control. It not only improves efficiency, but also provides important information for clinical diagnosis and treatment supporting information. The functions of laboratory physicians are likely to undergo corresponding transition and adjustment in the future. Therefore, it is a general trend to promote the development and leap of the next generation of laboratory medicine by artificial intelligence, and the future of laboratory medicine will usher in the "artificial intelligence era".

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Evolution of the radial distribution of a micro-crystalline structure within polyacrylonitrile monofilaments at various temperatures during carbonization was investigated via the method of synchrotron wide-angle X-ray diffraction (S-WAXD) and micro-scanning Raman spectroscopy. The result indicated that in the core region of the carbon fiber monofilaments, the L c is lower while the interplanar spacing (d 002) is higher compared with those in the skin region at 1300 °C. The difference between the skin and core regions in L c and d 002 constantly decreases as the heat treatment temperature increases. The results of micro-scanning Raman indicated that the micro-crystallites grow faster along the L a direction, and the graphite degree is higher in the skin region than that in the core region. This is attributed to the fact that the removal of nitrogen element is the domain factor on the growth of a pseudo-graphite crystallite at relatively lower heat treatment temperatures. As the temperature rises, L c is developed mainly in the core region with the closed packing of a graphite layer, while the crystallites in the skin region grow in both L a and L c directions, which are mainly affected by the disordered and boundary graphite structure.

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OBJECTIVE: To research for the identification of Dongchongxiacao [Cordyceps sinensis( Berk.) Sacc.] and its counterfeits-processed materials from Cordyceps taii Liang et Liu. METHODSE: On the basis of the specimens of Dongchongxiacao and four types of counterfeits, the macroscopic and microscopic identification methods were studied, including the comparison of the macroscopic features, such as insertion position of stroma, colour of caterpillar part, abdominal leg, and the microscopic features such as the transverse section of the stroma, the caterpillar's body wall and the planta of abdominal leg. RESULTS: The differences between Dongchongxiacao and four types of counterfeits were obvious in macroscopic and microscopic features. CONCLUSION: Dongchongxiacao and its counterfeits-processed materials from Cordyceps taii Liang et Liu. can be identified by the differernces of macroscopical and microscopical fetures.

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Objective:To study the role of ultraviolet fluorescence detection technology in personal protective equipment education (PPE) and training.Methods:A study was designed to inspect the risk of self-contamination during PPE doffing between 77 healthcare workers. Used a fluorescent tracer slurry which put on the hands, chest, abdomen, knees to simulate the contaminations. Self-contamination of scrubs and skin was measured using ultraviolet light visualization respectively.Results:According to the uv-fluorescer simulating study, 43 (55.8%) of the medical staff had contamination after the removal of PPE, and the main sites of contamination included: left side of the abdomen 11 (11.70%), left side of the chest 9 (9.57%), left forearm 6 (6.38%), left foot instep 6 (6.38%), neck 6 (6.38%), right shoulder 5 (5.32%), etc. Among them, the frequency of simulated fluorescence pollution in the group with working years less than 6 years was less than that in the other groups, and the difference was statistically significant compared with the group of 11-15 years ( t value was -3.685, P value was 0.001 ). Conclusion:Ultraviolet fluorescence labeling detection technology can directly, quickly and effectively evaluate and feedback the key contaminated parts in the process of using PPE, which can provide detailed evidence for redesigning PPE and improve the PPE training process to reduce the contamination.

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Network pharmacology and bioinformatics technology were used to predict the mechanism of action of Fuzi-Lizhong pill (FLP) in the treatment of ulcerative colitis (UC). 26 components (23 prototype compounds and 3 metabolites) in the blood of FLP were selected as the research objects. PharmMapper database, SwissTargetPrediction platform, GeneCards and OMIM database were used to screen and predict potential targets of FLP in blood. The protein-protein interaction network model was constructed by using String database and Cytoscape software. DAVID platform, KEGG and Reactome databases were used for GO analysis and pathway analysis of potential targets. Network of drug ingredients-targets-pathways was constructed by Cytoscape software. AutoDock vina software was used to dock the molecules of the absorbed ingredients of FLP in blood with the key targets. 82 potential targets of FLP for treatment of UC were obtained. Potential targets mainly involve biological processes such as response to organic substance, regulation of apoptosis, regulation of programmed cell death, which played roles in the treatment of UC by adjusting pathways in cancer, Colorectal cancer, Vascular endothelial growth factor signaling pathway, Mitogen-activated protein kinase signaling pathway, arachidonic acid metabolism and the other signal pathways. From the perspective of network pharmacology, this study predicted the mechanisms of action of FLP in treating UC, indicating that FLP in treating UC had the characteristics of multiple ingredients, multiple targets and multiple pathways, which laid a foundation for further research.

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OBJECTIVE@#To evaluate the clinical efficacy and safety of Congrong Shujing Granules ( , CSGs) in treating patients with Parkinson's disease (PD) and Chinese medicine (CM) syndrome of Shen (Kidney) essence deficiency, and to investigate the potential mechanism involving efficacy through a transcriptome sequencing approach.@*METHODS@#Eligible PD patients with syndrome of Shen essence defificiency were randomly assigned to a treatment group or a control group by a random number table, and were treated with CSGs combined with Western medicine (WM), or placebo combined with WM, respectively. Both courses of treatment lasted for 12 weeks. The Unifified Parkinson's Disease Rating Scale (UPDRS) score, the PD Question-39 (PDQ-39) score, CM Syndrome Scale score, and drug usage of all patients were evaluated before and after treatment. Safety was evaluated by clinical laboratory tests and electrocardiographs. Blood samples from 6 patients in each group were collected before and after the trial and used for transcriptomic analysis by gene ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis. Differentially expressed genes were validated using reverse transcription-polymerase chain reaction.@*RESULTS@#A total of 86 PD patients were selected from the Third Affifiliated People's Hospital of Fujian University of Traditional Chinese Medicine between January 2017 and December 2017. Finally, 72 patients completed the trial, including 35 in the treatment group and 37 in the control group. When compared with the control group after treatment, patients in the treatment group showed signifificant decreases in UPDRS sub-II score, PDQ-39 score, CM syndrome score, and Levodopa equivalent dose (P0.05). A possible mechanism of clinical effificacy was proposed that involved regulating cell metabolism-related processes and ribosome-related pathways. Treatment with CSGs had shown to affect relevant gene loci for PD, including AIDA, ANKRD36BP2, BCL2A1, BCL2L11, FTH1P2, GCH1, HPRT1, NFE2L2, RMRP, RPS7, TGFBR1, WIPF2, and COX7B.@*CONCLUSIONS@#CSGs combined with WM can be used to treat PD patients with CM syndrome of Shen essence defificiency with a good safety. The possible mechanism of action and relevant gene loci were proposed. (Registration No. ChiCTR-IOR-16008394).

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BACKGROUND: Tumoral calcinosis is an uncommon clinicopathological condition which is characterized by the formation of calcium salt deposition in intra-articular or peri-articular soft tissues. It usually presents as a focal growth of hard tissue, either solitary or multiple, beneath the skin and connective tissue. Diagnostic techniques mainly include clinical and radiographic evaluation. The most commonly involved locations include the hip, elbow, shoulder and knee. Involvement of the head and neck regions are far less common. There have been 5 case reports of temporomandibular joint involvement in the literature so far. CASE PRESENTATION: We present a case report which describes the diagnosis and management of a 59 year old female patient with chronic right temporomandibular joint pain and localized bony hard swelling over the right pre-auricular region. Patient retained normal range of motion and mouth opening. Computed tomography taken showed a radio-opaque juxta-articular ovoid mass over the right pre-auricular region in close proximity but not fused to the mandibular condyle. Surgical excision was performed for this swelling via a pre-auricular approach under general anaesthesia. Histological examination performed confirmed the diagnosis of tumoral calcinosis. Pain at the right temporomandibular joint was resolved after the surgery. Serum calcium and phosphate levels were normal in this patient. CONCLUSION: Surgical excision is the primary treatment modality for tumoral calcinosis. Tumoral calcinosis may be associated with elevated serum calcium and phosphate levels. In patients with elevated serum electrolytes, it is important to consider the overall systemic health in management of this condition. Management of serum electrolytes levels plays a role in reducing recurrence rates. This case report and review aims to discuss the diagnosis, treatment and overall systemic management of this rare condition.

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Although it has been half a century since polyacrylonitrile (PAN)-based carbon fibers were first developed, the exact formation mechanism of skin-core structure of PAN-based carbon fibers, especially the stabilized PAN fibers, was still not well clarified from the viewpoint of the chemical structure. In order to address this aforementioned challenge, a powerful tool with nanoscale resolution named photo-induced force microscopy was applied to map the chemical group distribution in the cross section of stabilized PAN fibers and reveal the evolution mechanism of skin-core structure throughout the whole stabilization process. The results indicated that the formation of skin-core structure of stabilized PAN fiber was attributed to the complex and overlapped chemical reactions caused by gradient of oxygen along radial direction and the formation of dense crystal layer at the interface between the skin and core part. Finally, the crystal layer was destroyed and the monofilaments tended to be homogeneous with further oxidation.

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Electron probe micro-analysis (EPMA), micro-beam wide angle X-ray diffraction (Micro-beam WAXD), micro-Raman and nano-infrared (nano-IR) spectroscopy were performed to characterize the hierarchical radial structure within polyacrylonitrile (PAN) fibre which was obtained by the wet-spinning method, including morphology, aggregation structure and molecular chain conformation. The results indicated that along the radial direction of the PAN fibre, the skin layer reflects denser morphology compared to the core region. The crystallinity, d-spacing of the (100) Miller plane and crystalline orientation in PAN fibres were gradually decreased from the skin layer to the central part, while the crystalline size shows opposite distribution tendency which was affected by the diffusion depending on the coagulation environment. As to the molecular chain structure, PAN chains tend to keep the helical conformation rather than planar zigzag conformation and packed more orderly in the skin layer of fibres.

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Objective:Based on the previous studies, to investigate the dissolution behavior of Fuzi Lizhongwan by simultaneously determining the dissolution of benzoylmesaconine, benzoylaconine and benzoylhypaconine in Aconiti Lateralis Radix Praeparata. Method:The simultaneous determination of benzoylmesaconine, benzoylaconine and benzoylhypaconine in Fuzi Lizhongwan was established by HPLC-QQQ-MS. The dissolution amounts of three compositions in 15 batches of Fuzi Lizhongwan from 5 manufacturers at different time points, the cumulative dissolution was calculated and the dissolution curve was drawn. The f2 similarity factor method was adopted to evaluate similarity of dissolution curves of index components in different batches of samples from the same manufacturer, and to evaluate similarity of dissolution curves of samples from different manufacturers based on the same index component. The dissolution model of Fuzi Lizhongwan was concluded by fitting with the dissolution data. Result:When hydrochloric acid solution with pH of 1.2 was used as the dissolution medium, the three alkaloids had the best dissolution effect. The dissolution behavior of three monoester alkaloids in Fuzi Lizhongwan was basically synchronous and the dissolution lasted for 24 h. Three batches of samples from the same manufacturer (manufacturer 1, 3, 4 and 5) appeared to be similar on dissolution behavior, indicating that the dissolution behavior of the majority of samples from different manufacturers was similar. The dissolution behavior of batch 1 sample was different from batch 2 and 3 samples in manufacturer 2, suggesting that the quality of different batches of samples in manufacturer 2 might be different. The fitting results of dissolution data of index components in samples from different manufacturers were consistent, and the Weibull model was the best. Conclusion:Index components in fifteen batches of samples from 5 manufacturers are continuously dissolved within 24 h, indicating that the samples have the characteristics of slow dissolution. The dissolution curves of samples from the same manufacturer are similar to each other, indicating that the quality of different batches of products from most manufacturers is stable. The dissolution behavior of benzoylmesaconine, benzoylaconine and benzoylhypaconine in samples form different manufacturers has some differences, which may be caused by the source of medicinal materials and preparation technology parameters.

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Objective: To establish the method for determining the content of Polygalae Radix (3,6'-disinapoylsucrose) and Glycyrrhizae Radix et Rhizoma (glycyrrhizic acid) in Fufang Jiegeng Zhike Pian,so as to know the overall quality condition of Fufang Jiegeng Zhike Pian and ensure the safety and effectiveness of public medication. Method: HPLC was performed of MG C18 chromatographic column (4.6 mm×250 mm,5 μm) and mobile phase acetonitrile-0.05% phosphoric acid solution were used to test Polygalae Radix (3,6'-disinapoylsucrose) and Glycyrrhizae Radix et Rhizoma (glycyrrhizic acid),with the sample amount of 20 μL,flow rate of 1.0 mL·min-1,and column temperature of 30℃,where the mobile phase acetonitrile-0.05% phosphoric acid solution and detection wavelength were 18:82 and 320 nm for Polygalae Radix (3,6'-disinapoylsucrose) and 35:65 and 250 nm for Glycyrrhizae Radix et Rhizoma (glycyrrhizic acid). Result: 3,6'-Disinapoylsucrose and glycyrrhizic acid presented high linearity with the peak area at 0.105 8-2.643 8 μg(r=0.999 5) and 0.077 0-5.773 0 μg (r=1.000 0) respectively,and the average recovery rate was 96.2%(RSD 1.2%) and 95.6%(RSD 0.9%). After content determination of Polygalae Radix and Glycyrrhizae Radix et Rhizoma in 178 batches of samples,it was found that some producers input no,only a few or even poor medicinal materials (medicinal slices) during production,and the quality varied a lot among products from different producers and products of different batches from a same producer. Conclusion: The method is simple,accurate,and highly reproducible and sensitive,providing scientific basis for the overall quality control of Fufang Jiegeng Zhike Pian.