Fractional-order electromagnetic modeling and identification for PMSM servo system.

An accurate electromagnetic model is essential for an optimal controller tuning of the high-performance servo system. This paper proposes a fractional-order electromagnetic model of a permanent magnet synchronous motor (PMSM) servo system and an identification methodology of this model. The reason why the investigated electromagnetic model should be a fractional-order one is addressed with a detailed explanation. The influence of voltage source inverter nonlinearity, which may cause system identification error, is analyzed. An improved inverter nonlinearity model and compensation method are proposed to promote the accuracy of the model parameter identification. Compared with the existing typical electromagnetic models of the PMSM servo system, the current open-loop and closed-loop experiments prove that the proposed fractional-order electromagnetic model with time delay is more accurate for the actual physical system. The effectiveness of the proposed nonlinearity modeling and compensation scheme of the inverter is also verified on an experimental PMSM servo system.

Active disturbance rejection control with fractional-order model-aided extended state observer.

Increasing the observer bandwidth of the extended state observer (ESO) can significantly enhance the disturbance rejection performance of the active disturbance rejection control (ADRC). However, a large observer bandwidth can also amplify the noise and degrade the control quality. This study proposes a novel fractional-order ADRC (FOADRC) approach. A fractional-order model-aided extended state observer (FOMESO) is designed by leveraging available plant information. Under a given observer bandwidth, the disturbance estimation performance of FOMESO is improved, while noise sensitivity is not aggravated. Additionally, FOMESO transforms a typical second-order plant into a fractional-order double-integrator model, reducing the phase lag to below 180∘. Consequently, the derivative component, which is sensitive to noise, is unnecessary in the feedback controller. Simulation and comprehensive comparisons demonstrate that the proposed FOADRC scheme outperforms the traditional ADRC in tracking, noise sensitivity, disturbance rejection, and stability. Furthermore, the proposed FOADRC approach is robust to plant parameter variations. The proposed method is validated through experiments on a permanent magnet synchronous motor speed servo system, confirming its superiority and effectiveness.

The Role and Positioning of Clinical Trial Ethics Review under Pharmaceutical Innovation Strategy / 中国医学伦理学

Ethical review runs through the whole process of drug clinical trials, and is a critical step to ensure the rights and interests of subjects. This paper analyzed and discussed the role and positioning of ethical review in new drug clinical trials, cleared the principles of ethical review, identified the responsibilities of ethical review, and clarified the authority of ethical review approval documents. The ethical review should primarily focus on the ethics of the clinical trials, not replace other professional institutions to review the clinical trials’ legality and scientific nature. Ethical approval is only one of the necessary conditions for conducting clinical trials, not the only factor. It is recommended to strengthen the publicity and popularization of scientific and technological ethics awareness, improve the clinical trial approval mechanism, and optimize the phrasing of ethical review approval documents. It is warranted to further optimize the quality of ethical review, improve the construction of ethical review system, ultimately achieve the unity of promoting innovation and preventing risks, so as to effectively realize the benign interaction between high-quality development of scientific and technological innovation and high-level safety.

The genus Datura L. (Solanaceae): A systematic review of botany, traditional use, phytochemistry, pharmacology, and toxicology.

The genus Datura has been used as an important traditional medicine in China, as well as in other countries worldwide. This review summarizes the latest progress and perspective of the genus Datura, from the aspects of botany, traditional uses, phytochemistry, pharmacology, and toxicology. Up to May 2022, literatures were collected from online scientific databases, including Google Scholar, PubMed, SciFinder, CNKI, ACS, and Web of Science, and information was also obtained from "Flora Republicae Populairs Sinicae", Chinese Pharmacopoeia, Chinese herbal classic books, and Ph.D. and M. Sc. dissertations. Studies on chemical constituents, pharmacological activities, and toxicity are mainly focused on D. metel, D. stramonium, and D. inoxia. Furthermore, 496 compounds have been discovered from the genus Datura, including withanolides, alkaloids, flavonoids, terpenoids, phenylpropanoids, steroids, amino acids, aromatics, and aliphatics. Among them, withanolides and alkaloids are two main active constituents. Pharmacological activities of extracts and compounds have been studied from the aspects of antitumor, antiinflammation, antioxidant, antimicrobial, antispasmodic, anticoagulant, analgesic, hypoglycemic and xanthine oxidase inhibitory activities, as well as the effects on central nervous system and immune system. Modern pharmacological studies have provided more clues to elucidate the traditional usages. The toxicity of the genus Datura is noteworthy, especially the potential toxicity on organs. This review would provide a comprehensive and constructive overview for new drug development and utilization of the genus Datura.

Coupling a 3D Lithophilic Skeleton with a Fluorine-Enriched Interface to Enable Stable Lithium Metal Anode.

Lithium (Li) metal anode is known as a potential anode candidate for next-generation high-energy-density rechargeable batteries. Nevertheless, the challenge caused by the uncontrollable Li dendrites' growth and the fragile solid electrolyte interface (SEI) layer seriously hinders the commercial application of Li metal batteries. Herein, we report a fluorine-enriched nitrogen-doped hollow carbon spheres decorated carbon fibers (FNCS@CF) skeleton which effectively integrates the uniformly distributed lithophilic sites and mechanically robust LiF-enriched SEI, thus endowing the composite Li metal anode with durable and dendrite-free features. The Li nucleation barrier is greatly reduced owing to the strong lithiophilicity characteristics of pyridinic/pyrrolic nitrogen. The fluorinated hollow carbon spheres can not only provide a powerful setting for Li deposition but can also promote the in situ formation of LiF-enriched SEI. As a result, the prepared FNCS@CF skeleton demonstrates excellent electrochemical performances such as ultrahigh average Coulombic efficiency of 99.6% over 240 cycles at 3 mA h cm-2 and remarkable cyclability (1300 h) with a low deposition overpotential of 10 mV. Furthermore, a FNCS@CF-Li|NCM full cell was also assembled which exhibits a prominent cycling stability and capacity retention even under simulated practical working conditions, i.e., low negative-to-positive capacity (N/P) ratio of 1.5 and lean electrolyte of 10 uL mAh-1.

Daturanolide A-C, Three New Withanolides from Datura metel L. and Their Cytotoxic Activities.

Three new withanolides (1-3), named as daturanolide A-C, along with six known withanolides (4-9) were isolated from the flowers of Datura metel L. Their structures with absolute configurations were elucidated by a series of spectroscopic methods, electronic circular dichroism (ECD) analyses, and X-ray crystallography. All the isolates were evaluated for cytotoxicity against five human cancer cell lines (HCT116, U87-MG, NCI-H460, BGC823, and HepG2), and 6 exhibited marked cytotoxicity.

Effect of enteral nutrition on nutritional status and tumor cell proliferation activity in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy / 中国医师进修杂志

Objective@#To explore the effect of enteral nutrition on tumor cell proliferation activity in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy.@*Methods@#Sixty-six rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy from January 2016 to January 2018 in the Yongchuan Hospital Affiliated to Chongqing Medical University were selected. The patients were divided into experimental group (enteral nutrition combined with neoadjuvant therapy) and control group (simple adjuvant therapy) according to the random digits table method, with 33 cases in each group. The expressions of proliferating cell nuclear antigen (PCNA) and Ki-67 antigen before and after treatment were detected by immunohistochemical method; the albumin and prealbumin before and after treatment were observed, and the nutrition risk screening 2002 (NRS2002) was evaluated.@*Results@#There were no statistical differences in the expressions of PCNA and Ki-67 antigen before treatment between 2 groups (P>0.05); the expressions of PCNA and Ki-67 antigen after treatment in experimental group were significantly lower than those in control group, and there were statistical differences (P<0.05). There were no statistical differences in the NRS2002 score, albumin and prealbumin before treatment between 2 groups (P>0.05); the NRS2002 score after treatment in experimental group was significantly lower than that in control group: (1.58 ± 0.50) scores vs. (3.65 ± 0.72) scores, the albumin and prealbumin after treatment were significantly higher than those in control group: (35.92 ± 2.77) g/L vs. (31.12 ± 1.76) g/L and (204.58 ± 23.86) mg/L vs. (157.46 ± 18.99) mg/L, and there were statistical differences (P<0.01).@*Conclusions@#Enteral nutrition can reduce the proliferation activity of tumor cell in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy, and it can improve the nutritional status of patients.

Effect of enteral nutrition on nutritional status and tumor cell proliferation activity in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy / 中国医师进修杂志

Objective To explore the effect of enteral nutrition on tumor cell proliferation activity in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy. Methods Sixty-six rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy from January 2016 to January 2018 in the Yongchuan Hospital Affiliated to Chongqing Medical University were selected. The patients were divided into experimental group (enteral nutrition combined with neoadjuvant therapy) and control group (simple adjuvant therapy) according to the random digits table method, with 33 cases in each group. The expressions of proliferating cell nuclear antigen (PCNA) and Ki-67 antigen before and after treatment were detected by immunohistochemical method; the albumin and prealbumin before and after treatment were observed, and the nutrition risk screening 2002 (NRS2002) was evaluated. Results There were no statistical differences in the expressions of PCNA and Ki-67 antigen before treatment between 2 groups (P＞0.05); the expressions of PCNA and Ki-67 antigen after treatment in experimental group were significantly lower than those in control group, and there were statistical differences (P﹤0.05). There were no statistical differences in the NRS2002 score, albumin and prealbumin before treatment between 2 groups (P＞0.05); the NRS2002 score after treatment in experimental group was significantly lower than that in control group: (1.58 ± 0.50) scores vs. (3.65 ± 0.72) scores, the albumin and prealbumin after treatment were significantly higher than those in control group: (35.92 ± 2.77) g/L vs. (31.12 ± 1.76) g/L and (204.58 ± 23.86) mg/L vs. (157.46 ± 18.99) mg/L, and there were statistical differences (P﹤0.01). Conclusions Enteral nutrition can reduce the proliferation activity of tumor cell in rectal cancer patients with nutritional risk treated with preoperative neoadjuvant therapy, and it can improve the nutritional status of patients.

Evolution of the hemagglutinin gene of influenza A( H7N9) virus in China between 2013 and 2017 / 医学研究生学报

Objective Influenza A(H7N9) virus causes a relatively high mortality in humans and therefore it is of great sig-nificance to know its prevalence in China .This article aimed to study the genetic characteristics and evolution of the hemagglutinin (HA) gene of the influenza A(H7N9) virus prevailing in China between 2013 and 2017. Methods We downloaded the HA se-quences of the influenza A ( H7N9) virus prevailing in China between 2013 and 2017 from The Global Initiative on Sharing All Influen-za Data and National Center for Biotechnology Information .Using the bioinformatics software , we analyzed the homology , molecular characteristics , phyletic evolution , and selective pressure of the HA gene. Results The homology of the HA gene of the influenza A ( H7N9) virus and the reference strain was decreasing each year from 2013 to 2017, 99.0%-99.9%in 2013, 98.7%-99.5%in 2014, 98.4%-99.6%in 2015, 76.8%-99.4%in 2016, and 69.9%-98.2%in 2017.Compared with the reference strain , the HA gene of the influ-enza A(H7N9) virus underwent variations in 21 antigenic sites.The variation of N285D was the highest (23%) in 2015 and that of R148K increased yearly,reaching 65%in 2016 and 78.5% in 2017. Phylogenetic analysis showed a concentrative distribution of the influenza A ( H7N9) virus strains on the phylogenetic tree in the same year from 2013 to 2017.Amino acid substitution of T 140A was observed in most of the influenza A ( H7N9) virus strains from Guang-dong in 2013, and the widest distribution of the virus strains was found in 2014.Positive selective pressure site 65 was obtained in the sequence of 2015 using the FEL and IFEL models, but not in the strains of 2016 or 2017. Conclusion Influenza A(H7N9) virus constantly undergoes variation , which has increased the difficulty in its prevention and control .More importance should be attached to observation of the virus and response to its adaptive mutations .

Evolution of the hemagglutinin gene of influenza A( H7N9) virus in China between 2013 and 2017 / 医学研究生学报

Objective Influenza A(H7N9) virus causes a relatively high mortality in humans and therefore it is of great sig-nificance to know its prevalence in China .This article aimed to study the genetic characteristics and evolution of the hemagglutinin (HA) gene of the influenza A(H7N9) virus prevailing in China between 2013 and 2017. Methods We downloaded the HA se-quences of the influenza A ( H7N9) virus prevailing in China between 2013 and 2017 from The Global Initiative on Sharing All Influen-za Data and National Center for Biotechnology Information .Using the bioinformatics software , we analyzed the homology , molecular characteristics , phyletic evolution , and selective pressure of the HA gene. Results The homology of the HA gene of the influenza A ( H7N9) virus and the reference strain was decreasing each year from 2013 to 2017, 99.0%-99.9%in 2013, 98.7%-99.5%in 2014, 98.4%-99.6%in 2015, 76.8%-99.4%in 2016, and 69.9%-98.2%in 2017.Compared with the reference strain , the HA gene of the influ-enza A(H7N9) virus underwent variations in 21 antigenic sites.The variation of N285D was the highest (23%) in 2015 and that of R148K increased yearly,reaching 65%in 2016 and 78.5% in 2017. Phylogenetic analysis showed a concentrative distribution of the influenza A ( H7N9) virus strains on the phylogenetic tree in the same year from 2013 to 2017.Amino acid substitution of T 140A was observed in most of the influenza A ( H7N9) virus strains from Guang-dong in 2013, and the widest distribution of the virus strains was found in 2014.Positive selective pressure site 65 was obtained in the sequence of 2015 using the FEL and IFEL models, but not in the strains of 2016 or 2017. Conclusion Influenza A(H7N9) virus constantly undergoes variation , which has increased the difficulty in its prevention and control .More importance should be attached to observation of the virus and response to its adaptive mutations .

Laparoscopic versus open liver resection for elderly patients with malignant liver tumors / 上海预防医学

Objective To compare the curative effect and short-term benefits of laparoscopic liver resection with open liver resection in elderly patients with malignant liver tumors and medical comorbidities.Methods Patients aged 70 and over who received liver resections for malignant liver tumors between January and October 2015 were enrolled.The perioperative outcomes of 17 patients with laparoscopic approach were matched and compared with those of 34 patients with conventional open approach in a 1:2 ratio.Results There was no significant difference found between the two groups with regard to age,gender,incidence of comorbid illness,hepatitis B positivity,and Child-Pugh grading of liver function.The median tumor size was 3 cm for both groups.The types of liver resection were similar between the two groups with no significant difference in the duration of operation (laparoscopic: 195 min vs.open: 210 min,P=0.436).The perioperative blood loss was 150 mL in the laparoscopic group and 330 mL in the open group (P=0.046) with no significant difference in the number of patients with blood transfusion.The duration of hospital stay was 6 days (3-15 days) for the laparoscopic group and 8 days (5-105 days) for the open group (P=0.005).Conclusion Laparoscopic liver resection is safe and feasible for elderly patients.The short-term benefits of laparoscopic approach proves to be evident for geriatric oncological liver surgery.

Clinical study of preoperative enteral nutrition in elderly colorectal cancer patients with nutritional risk / 重庆医学

Objective To observed the influence of preoperative enteral nutrition(EN) on postoperative nutritional status,immune function and complications in elderly patients with colorectal cancer complicating nutritional risk.Methods The NRS2002 nutritional risk screening criteria was used to select 70 elderly patients with colorectal cancer complicating nutritional risk,including 36 cases in the EN group and 34 cases in the control group.The EN support was given in the ENN group on preoperative 3 d.The levels of plasma total protein,prealbumin,albumin,transferrin,total lymphocyte count,plasma D-lactate(D-LAC) and plasma diamine oxidase (DAO) were detected on postoperative 1,3,5 7 d.The intraoperative intestinal cleanliness and postoperative complications were observed.Results The levels of plasma total protein,prealbumin,albumin,transferrin and total lymphocyte count in the EN group were significantly higher than those in the control group and the levels of D-LAC and DAO,and the incidence rates of abdominal infection and wound infection were significantly lower than those in the control group,the differences were statistically significant(P＜0.05).There was no statistically significant differences in the incidence rates of intestinal cleanliness and anastomotic leakage between the two groups (P＞0.05).Conclusion Preoperative EN support therapy in the patients with colorectal cancer complicating nutritional risk can significantly improve clinical prognosis.

Efficacy Observation of Cetuxizumab or Bevacizumab Combined with FOLFOX4 Regimen in the Treat-ment of Advanced Rectal Cancer / 中国药房

OBJECTIVE:To observe clinical efficacy of bevacizumab or cetuxizumab combined with FOLFOX4 regimen in the treatment of advanced rectal cancer. METHODS:114 patients with rectal cancer were randomly assigned to cetuxizumab group and bevacizumab group,with 57 cases in each group,among which one patient of bevacizumab group withdrew from therapy. Both groups received FOLFOX4 regimen:oxaliplatin 85 mg/m2+calcium folinate 200 mg/m2,ivgtt,2 h,and 5-FU 400 mg/m2,ivgtt, last,5-FU 600 mg/m2,ivgtt,22 h. Cetuxizumab group was additional given cetuxizumab 500 mg/m2;bevacizumab group was addi-tionally given bevacizumab 5 mg/kg,ivgtt. A treatment course lasted for 2 weeks. Both groups received 4 courses of treatment,and then clinical efficacy,toxic reaction and progression-free survival (PFS) were evaluated. RESULTS:Objective remission rate (RR),disease control rate(DCR)and median PFS of cetuxizumab group was 45.61%,92.98%and 10.0 months,those of bevaci-zumab group were 48.21%,87.50%and 11.0 months;there was no statistical significance between 2 groups(P>0.05). No signifi-cant differences were found in the incidence of ADR such as sensory neurotoxicity,aleucocytosis,thrombopenia,nausea and vomit-ing,diarrhea and erythra between 2 groups(P>0.05). CONCLUSIONS:Both bevacizumab or cetuxizumab combined with FOLF-OX4 regimen have a similar effect on patients with advanced cancer,with low incidence of toxic reaction.