Highly reversible extrinsic electrocaloric effects over a wide temperature range in epitaxially strained SrTiO3 films.

Electrocaloric effects have been experimentally studied in ferroelectrics and incipient ferroelectrics, but not incipient ferroelectrics driven ferroelectric using strain. Here we use optimally oriented interdigitated surface electrodes to investigate extrinsic electrocaloric effects in low-loss epitaxial SrTiO3 films near the broad second-order 243 K ferroelectric phase transition created by biaxial in-plane coherent tensile strain from DyScO3 substrates. Our extrinsic electrocaloric effects are an order of magnitude larger than the corresponding effects in bulk SrTiO3 over a wide range of temperatures including room temperature, and unlike electrocaloric effects associated with first-order transitions they are highly reversible in unipolar applied fields. Additionally, the canonical Landau description for strained SrTiO3 films works well if we set the low-temperature zero-field polarization along one of the in-plane pseudocubic <100> directions. In future, similar strain engineering could be exploited for other films, multilayers and bulk samples to increase the range of electrocaloric materials for energy efficient cooling.

[Safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy: A prospective, multi-center, single arm trial].

Objective: To evaluate the safety of double and a half layered esophagojejunal anastomosis in radical gastrectomy. Methods: This prospective, multi-center, single-arm study was initiated by the Affiliated Cancer Hospital of Zhengzhou University in June 2021 (CRAFT Study, NCT05282563). Participating institutions included Nanyang Central Hospital, Zhumadian Central Hospital, Luoyang Central Hospital, First Affiliated Hospital of Henan Polytechnic University, First Affiliated Hospital of Henan University, Luohe Central Hospital, the People's Hospital of Hebi, First People's Hospital of Shangqiu, Anyang Tumor Hospital, First People's Hospital of Pingdingshan, and Zhengzhou Central Hospital Affiliated to Zhengzhou University. Inclusion criteria were as follows: (1) gastric adenocarcinoma confirmed by preoperative gastroscopy;(2) preoperative imaging assessment indicated that R0 resection was feasible; (3) preoperative assessment showed no contraindications to surgery;(4) esophagojejunostomy planned during the procedure; (5) patients volunteered to participate in this study and gave their written informed consent; (6) ECOG score 0-1; and (7) ASA score I-III. Exclusion criteria were as follows: (1) history of upper abdominal surgery (except laparoscopic cholecystectomy);(2) history of gastric surgery (except endoscopic submucosal dissection and endoscopic mucosal resection); (3) pregnancy or lactation;(4) emergency surgery for gastric cancer-related complications (perforation, hemorrhage, obstruction); (5) other malignant tumors within 5 years or coexisting malignant tumors;(6) arterial embolism within 6 months, such as angina pectoris, myocardial infarction, and cerebrovascular accident; and (7) comorbidities or mental health abnormalities that could affect patients' participation in the study. Patients were eliminated from the study if: (1) radical gastrectomy could not be completed; (2) end-to-side esophagojejunal anastomosis was not performed during the procedure; or (3) esophagojejunal anastomosis reinforcement was not possible. Double and a half layered esophagojejunal anastomosis was performed as follows: (1) Open surgery: the full thickness of the anastomosis is continuously sutured, followed by embedding the seromuscular layer with barbed or 3-0 absorbable sutures. The anastomosis is sutured with an average of six to eight stitches. (2) Laparoscopic surgery: the anastomosis is strengthened by counterclockwise full-layer sutures. Once the anastomosis has been sutured to the right posterior aspect of the anastomosis, the jejunum stump is pulled to the right and the anastomosis turned over to continue to complete reinforcement of the posterior wall. The suture interval is approximately 5 mm. After completing the full-thickness suture, the anastomosis is embedded in the seromuscular layer. Relevant data of patients who had undergone radical gastrectomy in the above 12 centers from June 2021 were collected and analyzed. The primary outcome was safety (e.g., postoperative complications, and treatment). Other studied variables included details of surgery (e.g., surgery time, intraoperative bleeding), postoperative recovery (postoperative time to passing flatus and oral intake, length of hospital stay), and follow-up conditions (quality of life as assessed by Visick scores). Result: [1] From June 2021 to September 2022,457 patients were enrolled, including 355 men and 102 women of median age 60.8±10.1 years and BMI 23.7±3.2 kg/m2. The tumors were located in the upper stomach in 294 patients, mid stomach in 139; and lower stomach in 24. The surgical procedures comprised 48 proximal gastrectomies and 409 total gastrectomies. Neoadjuvant chemotherapy was administered to 85 patients. Other organs were resected in 85 patients. The maximum tumor diameter was 4.3±2.2 cm, number of excised lymph nodes 28.3±15.2, and number of positive lymph nodes five (range one to four. As to pathological stage,83 patients had Stage I disease, 128 Stage II, 237 Stage III, and nine Stage IV. [2] The studied surgery-related variables were as follows: The operation was successfully completed in all patients, 352 via a transabdominal approach, 25 via a transhiatus approach, and 80 via a transthoracoabdominal approach. The whole procedure was performed laparoscopically in 53 patients (11.6%), 189 (41.4%) underwent laparoscopic-assisted surgery, and 215 (47.0%) underwent open surgery. The median intraoperative blood loss was 200 (range, 10-1 350) mL, and the operating time 215.6±66.7 minutes. The anastomotic reinforcement time was 2 (7.3±3.9) minutes for laparoscopic-assisted surgery, 17.6±1.7 minutes for total laparoscopy, and 6.0±1.2 minutes for open surgery. [3] The studied postoperative variables were as follows: The median time to postoperative passage of flatus was 3.1±1.1 days and the postoperative gastrointestinal angiography time 6 (range, 4-13) days. The median time to postoperative oral intake was 7 (range, 2-14) days, and the postoperative hospitalization time 15.8±6.7 days. [4] The safety-related variables were as follows: In total, there were 184 (40.3%) postoperative complications. These comprised esophagojejunal anastomosis complications in 10 patients (2.2%), four (0.9%) being anastomotic leakage (including two cases of subclinical leakage and two of clinical leakage; all resolved with conservative treatment); and six patients (1.3%) with anastomotic stenosis (two who underwent endoscopic balloon dilation 21 and 46 days after surgery, the others improved after a change in diet). There was no anastomotic bleeding. Non-anastomotic complications occurred in 174 patients (38.1%). All patients attended for follow-up at least once, the median follow-up time being 10 (3-18) months. Visick grades were as follows: Class I, 89.1% (407/457); Class II, 7.9% (36/457); Class III, 2.6% (12/457); and Class IV 0.4% (2/457). Conclusion: Double and a half layered esophagojejunal anastomosis in radical gastrectomy is safe and feasible.

[Efficacy and safety of extracorporeal membrane oxygenation-supported percutaneous coronary intervention in chronic coronary total occlusion patients with reduced left ventricular ejection fraction].

Objective: To investigate the feasibility and safety of extracorporeal membrane oxygenation (ECMO)-supported percutaneous coronary intervention (PCI) in chronic coronary total occlusion (CTO) patients with reduced left ventricular ejection fraction (LVEF). Methods: The CTO patients with LVEF≤35% and undergoing CTO-PCI assisted by ECMO in the General Hospital of Northern Theater Command from December 2018 to March 2022 were enrolled in this study. The post-procedure complications, changes of LVEF from pre-procedure to post-procedure during hospitalization, and the incidence of all-cause mortality and changes of LVEF after discharge were assessed. Results: A total of 17 patients aged (59.4±11.8) years were included. There were 14 males. The pre-procedure LVEF of these patients were (29.00±4.08)%. Coronary angiography results showed that there were 29 CTO lesions in these 17 patients. There was 1 in left main coronary artery, 7 in left anterior descending artery, 11 in left circumflex artery, and 10 in right coronary artery. ECMO was implanted in all patients before procedure. Among 25 CTO lesions attempted to cross, 24 CTO were successfully implanted with stents. All patients underwent successful PCI for at least one CTO lesion. The number of drug-eluting stents implantation per patient were 4.6±1.3. After procedure, there were 8 patients with hemoglobin decreased>20 g/L, and 1 patient with ECMO-access-site related bleeding. The LVEF value at a median duration of 2.5 (2.0-5.5) days after procedure significantly increased to (38.73±7.01)% (P<0.001 vs. baseline). There were no in-hospital deaths. Patients were followed up for 360 (120, 394) days after discharge, 3 patients died (3/17). The LVEF value was (41.80±7.32)% at 155 (100, 308) days after discharge, which was significantly higher than the baseline value (P<0.001). Conclusion: The results of present study demonstrate that it is feasible, efficient and safe to perform ECMO)-supported CTO-PCI in CTO patients with reduced LVEF.

[Clinical characteristics and prognostic analysis of female patients with Stanford type B aortic dissection].

Objective: To explore the clinical characteristics and prognostic factors of female patients with Stanford type B aortic dissection. Methods: This is a single-centre retrospective study. Consecutive patients diagnosed with Stanford type B aortic dissection in General Hospital of Northern Theater Command from June 2002 to August 2021 were enrolled, and grouped based on sex. According to the general clinical conditions and complications of aortic dissection tear, patients were treated with thoracic endovascular aortic repair, surgery, or optimal medication. The clinical characteristics and aortic imaging data of the patients at different stages were collected, adverse events including all-cause deaths, stroke, and occurrence of aortic-related adverse events were obtained during hospitalization and within 30 days and at 1 and 5 years after discharge. According to the time of death, death was classified as in-hospital death, out-of-hospital death, and in-hospital death was divided into preoperative death, intraoperative death and postoperative death. According to the cause of death, death was classified as aortic death, cardiac death and other causes of death. Aortic-related adverse events within 30 days after discharge included new paraplegia, post-luminal repair syndrome, and aortic death; long-term (≥1 year after discharge) aortic-related adverse events included aortic death, recurrent aortic dissection, endoleak and distal ulcer events. The clinical characteristics, short-term and long-term prognosis was compared between the groups. Logistic regression analysis was used to explore the association between different clinical factors and all-cause mortality within 30 days in female and male groups separately. Results: A total of 1 094 patients with Stanford type B aortic dissection were enrolled, mean age was (53.9±12.1) years, and 861 (78.7%) were male and 233 (21.3%) were female. (1) Clinical characteristics: compared with male patients, female patients were featured with older average age, higher proportion of aged≥60 years old, back pain, anemia, optimal medication treatment, and higher cholesterol level; while lower proportion of smoking and drinking history, body mass index, calcium antagonists use, creatine kinase level, and white blood cell count (all P<0.05). However, there was no significant difference in dissection tear and clinical stage, history of coronary heart disease, diabetes, hypertension, and cerebrovascular disease between female and male patients (all P>0.05). (2) Follow-up result: compared with male patients, female patients had a higher rate of 30-day death [6.9% (16/233) vs. 3.8% (33/861), P=0.047], in-hospital death (5.6% (13/233) vs. 2.7% (23/861), P=0.027), preoperative death (3.9% (9/233) vs. 1.5% (12/861), P=0.023) and aorta death (6.0% (14/233) vs. 3.1% (27/861), P=0.041). The 1-year and 5-year follow-up results demonstrated that there were no significant differences in death, cerebrovascular disease, and aorta-related adverse events between the two groups (all P>0.05). (3) Prognostic factors: the results of the univariate logistic regression analysis showed that body mass index>24 kg/m2 (HR=1.087, 95%CI 1.029-1.149, P=0.013), history of anemia (HR=2.987, 95%CI 1.054-8.468, P=0.032), hypertension (HR=1.094, 95%CI 1.047-1.143, P=0.040) and troponin-T>0.05 µg/L (HR=5.818, 95%CI 1.611-21.018, P=0.003)were associated with an increased risk of all-cause mortality within 30 days in female patients. Conclusions: Female patients with Stanford type B aortic dissection have specific clinical characteristics, such as older age at presentation, higher rates of anemia and combined back pain, and higher total cholesterol levels. The risk of death within 1 month is higher in female patients than in male patients, which may be associated with body mass index, hypertension, anemia and troponin-T, but the long-term prognosis for both female and male patients is comparable.

[Formation of professor Mao Xiejun's thoughts on stomatological education].

Professor Mao Xiejun wrote a report about dental education of China in 1935. From 1948 to 1950, he published three articles containing the educational idea of "developing dentistry into stomatology". When he served as the director of the Faculty of Dentistry of Peking University Medical School in July 1950, he proposed to rename the Faculty of Dentistry into the Faculty of Stomatology,which were approved by the Ministry of Health and the Ministry of Education of the People's Republic of China in one month. The Chinese Medical Association established the Society of Stomatology the next year. Later, dentistry was successively changed into stomatology, and medical content was integrated into dental education, which was of great significance and far-reaching influence. During the developments of the thought of stomatological education in China, Professor Mao Xiejun evidently played a pivotal role. In this paper, the formation process of the thoughts of stomatological education related to professor Mao Xiejun's contribution is elucidated through studying the archives, personal letters, and historical documents, so as to enrich the researches on the history of stomatology in China and to facilitate better understanding and promoting the development of stomatology.

SrB4O7:Sm2+ fluorescence improves the accuracy of temperature measurements in externally heated diamond anvil cells.

The sample temperature in an externally heated diamond anvil cell (EHDAC) is generally measured by a thermocouple fixed to the pavilions of diamond anvils, ignoring the temperature difference between the thermocouple and the sample. However, the measured temperature depends strongly on the placement of the thermocouple, thus seriously reducing the accuracy of the temperature measurement and hindering the use of EHDAC in experiments requiring precise temperature measurements, such as high-pressure melting and phase-diagram investigations. In this study, the full width at half maximum (FWHM) of the 0-0 fluorescence line of strontium borate doped with bivalent samarium ions (SrBO4:Sm2+, SBO) is found to be highly sensitive to temperature and responds extremely rapidly to small temperature fluctuations, which makes it an excellent temperature indicator. We propose herein a precise method to measure temperature that involves measuring the FWHM of the 0-0 fluorescence line of SBO. This method is used to correct the temperature discrepancy between the thermocouple and the sample in an EHDAC. These corrections significantly improve the accuracy of temperature measurements in EHDACs. The accuracy of this method is verified by measuring the melting point of tin at ambient pressure. We also use this method to produce a tentative elementary phase diagram of tin up to 109 GPa and 495 K. This method facilitates high-pressure, high-temperature experiments demanding accurate temperature measurements in various disciplines. The study also discusses, in general, the experimental approach to measuring temperature.

[Epidemiological characteristics of two local COVID-19 outbreaks caused by 2019-nCoV Omicron variant in Guangzhou, China].

Objective: To understand the epidemiological characteristics of two local COVID-19 outbreaks caused by 2019-nCoV Omicron variant in Guangzhou, such as incubation period, serial interval, basic reproductive number (R0) and the influence of gathering places on R0, and provide evidence for the prevention and control of Omicron variant infection. Methods: The data of daily confirmed cases of Omicron variant infection from April 8 to May 8, 2022 in two COVID-19 outbreaks in Guangzhou were collected for model fitting. Weibull, Gamma and lognormal distribution were used to estimate incubation period and serial interval. Exponential growth method and the maximum likelihood estimation were used to estimate R0. Results: The median of incubation period was 2.94 (95%CI: 2.52-3.38) days and median of serial interval was 3.32 (95%CI: 2.89-3.81) days. The estimated R0 in small-size place was 4.40 (95%CI: 3.95-4.85), while the estimated R0 at airport was 11.35 (95%CI: 11.02-11.67). Conclusion: The incubation period of Omicron variant in two local COVID-19 outbreaks in Guangzhou is significantly shorter than that of delta variant. The higher the gathering degree in a place, the larger the R0. Due to its rapid transmission, COVID-19 epidemic is prone to occur. Therefore, the COVID-19 prevention and control strategy should be dynamically adjusted in time.

The genera Coccus and Prococcus (Hemiptera: Coccomorpha: Coccidae) in China, with two new combinations and descriptions of two new species.

The Chinese soft scale species in the genus Coccus Linnaeus, 1758 (Hemiptera: Coccomorpha: Coccidae) were studied. Coccus cambodiensis Takahashi and the Malaysian species C. cameronensis Takahashi are considered to be non-congeneric with Coccus hesperidum Linnaeus, 1758, the type species of Coccus, and are transferred to Prococcus Avasthi, 1993, as Prococcus cambodiensis (Takahashi, 1942), comb. n. and Prococcus cameronensis (Takahashi, 1952), comb. n. The generic diagnosis of Prococcus is revised. In the genus Coccus, two new species are described and illustrated based on adult females: Coccus nanningensis Cao Feng, sp. n. from Guangxi, China, on Ficus carica (Moraceae), and Coccus cephalotaxus Cao Feng, sp. n. from Shannxi, China, on Cephalotaxus sinensis (Taxaceae). Identification keys to separate adult females of Prococcus from Coccus, the 14 species of Coccus found in China, and all three species of Prococcus are provided.

[One-year follow-up results of atrial fibrillation patients who undergoing transcatheter aortic valve implantation].

Objective: To investigate whether atrial fibrillation (AF) before transcatheter aortic valve implantation (TAVI) will affect the prognosis of patients post TAVI. Methods: This is a single center retrospective study. A total of 115 patients with severe aortic stenosis (AS) who were admitted to General Hospital of Northern Theater Command from May 2016 to November 2020 and successfully received TAVI treatment were included. According to absence or accompaniment of AF pre-TAVI, they were divided into AF group (21 cases) and non-AF group (94 cases). The patients were followed up for postoperative antithrombotic treatment and the occurrence of the net adverse clinical and cerebrovascular events (NACCE) at 12 months post TAVI, including cardiogenic death, readmission to hospital for heart failure, nonfatal myocardial infarction, ischemic stroke and severe bleeding (BARC levels 3-5). Univariate logistic regression was used to analyze the related factors of NACCE. Results: Among the 115 selected patients, age was (73.8±6.9) years, there were 63 males. And 21 cases (18.2%) were diagnosed as AFbefore TAVI. In terms of postoperative antithrombotic therapy, 48.9% (46/94) of the patients in the non-AF group received monotherapy and 47.9% (45/94) received dual antiplatelet therapy. In the AF group, 47.6% (10/21) received anticoagulants and 33.3% (7/21) received dual antiplatelet therapy. The proportion of patients in the AF group taking non-vitamin K antagonist oral anticoagulants (NOAC) was higher than that in the non-AF group (38.1% (8/21) vs. 2.1% (2/94), P<0.001). Patients in both groups were followed up to 12 months after TAVI. During the 12 months follow-up, the incidence of NACCE after TAVI was 14.3% (3/21) in the AF group, which was numerically higher than that in the non-AF group (6.4% (6/94)), but the difference was not statistically significant (P=0.441). The incidence of severe bleeding was significantly higher in the AF group than in the non-AF group (9.5% (2/21) vs. 0, P=0.032). Univariate logistic regression analysis showed that hypertension was associated with the risk of NACCE (OR=8.308, P=0.050), while AF was not associated with the risk of NACCE (P=0.235). Conclusion: The incidence of severe bleeding after TAVI is higher in patients with AF than in patients without AF prior TAVI, and there is a trend of increased risk of NACCE post TAVI in AF patients.

Tunable electronic properties and related functional devices for ferroelectric In2Se3/MoSSe van der Waals heterostructures.

In recent years, two-dimensional (2D) materials have attracted increasing attraction in a number of scientific research fields. In particular, ferroelectric materials with reversible spontaneous electric polarization and Janus transition metal dichalcogenides (TMDs) with intrinsic dipoles exhibit novel properties for many practical applications. Here, the electronic properties of van der Waals (vdW) heterostructures consisting of In2Se3 and MoSSe were investigated based on a first-principles approach. It was demonstrated that four studied In2Se3/MoSSe heterostructures exhibited obvious band gap (E g) differences, ranging 0.13 to 0.90 eV for PBE (0.47 to 1.50 eV for HSE06) owing to the reversible spontaneous electric polarization of In2Se3 and different intrinsic dipole of MoSSe, and different band alignments of type-I or type-II could also be obtained. The energy bands of the four vdW heterostructures could be obviously regulated by varying degrees of vertical (horizontal) strain and vertical interface electric field, and the E g varied from zero to 1.27 eV. Then, M4-based mechanical switching devices and ferroelectric diodes were designed based on the significant strain and electric field function. These results provide one possible mechanism for how the polarization direction regulates the physical properties of the system due to the different charges on the two surfaces of the out-of-plane polarized ferroelectric material, which may lead to different proximity effects on the face of the material.

[Perioperative serious complications in patients undergoing transcatheter aortic valve replacement: a single-center experience].

Objective: To observe the incidence of perioperative severe complications in aortic stenosis (AS) patients undergoing transcatheter aortic valve implantation (TAVR), and to explore the influence of the accumulated experience of the operators on the incidence of complications. Methods: This is a single-center retrospective study. Patients with AS who underwent TAVR from May 2016 to November 2020 in General Hospital of Northern Theater Command were included. The occurrence of severe complications during perioperative period was recorded. Severe complications included all-cause death, surgical transfer to thoracotomy, coronary artery occlusion, peripheral vascular approach complications, severe cerebrovascular events, moderate or above perivalvular leakage, valve displacement (implanted valve middle valve), pacemaker implantation, etc. In order to observe the influence of the accumulated experience of the operators on the occurrence of postoperative complications, the complications in each stage of the patients were counted and the bar chart was drawn with interval of every 30 patients. Results: A total of 119 patients were included, including 64 males and 55 females, the mean age was (73.9±6.9) years. The valve implantation was unsuccessful in 3 out of 119 patients (2.5%). There were 39 cases of severe complications during perioperative period, including 1 death (0.8%), 2 cases of thoracotomy (1.7%), 2 cases of coronary artery occlusion (1.7%), 8 cases of peripheral vascular approach complications (6.7%), and 1 case of new severe cerebrovascular event (0.8%), 3 cases of moderate or higher perivalvular leakage (2.5%), 8 cases of valve displacement leads to midvalvular implantation (6.7%), 14 cases of permanent pacemaker implantation due to new atrioventricular block (11.8%). The bar chart showed that the incidence of permanent pacemaker implantation and in-valve implantation did not significantly decrease with the accumulation of experience, while the incidence of other complications showed a decreasing trend after 30 cases. Conclusions: Most serious complications occurred in the early stage of TAVR in our center. The incidence of all cause death, coronary artery occlusion and peripheral vascular approach complications in the perioperative period post TAVR could be reduced in the TAVR center in the learning stage through the accumulation of procedure-related experience, but the incidence of pacemaker placement and the implanted valve within the valve dose not significantly decrease over time.

Genome-wide DNA methylation and transcription analysis in tongue and biceps femoris muscles of cloned pigs with macroglossia.

Cloned animals are prone to abnormal phenotypes such as enlarged tongue, fetal oversize, and progeria. In the present study, whole-genome bisulfite sequencing and mRNA sequencing were performed on tongue and biceps femoris muscles of cloned piglets with and without macroglossia, in an attempt to elucidate the epigenetic causes of the macroglossia phenotype. We identified 14 958 and 18 752 differentially methylated regions in the tongue and biceps femoris muscles, respectively, of macroglossia piglets and these correspond to 4574 and 4772 differentially methylated genes compared with the control group (piglets without macroglossia). Larger methylation difference was found in tongue muscle than in biceps femoris muscle. In total, 114 genes in tongue and 72 genes in biceps femoris muscles were found to be differentially expressed between the two groups. Of these differentially expressed genes in tongue muscle, 31 were also differentially methylated genes, among which DIO3 and ZIC1 were imprinting or predicted imprinting genes. These two and another six overlapping genes (ALDH1A2, MKX, MAB21L2, CA3, RANBP3L, and MYL10) are crucial factors involved in embryonic development or tissue and organ development. GO enrichment analysis suggested possible alteration of these processes. Our study provides novel molecular insights into the formation of macroglossia in cloned pigs.

[Five-year clinical outcomes of the second generation biodegradable polymer sirolimus-eluting stent (EXCROSSAL) in treating patients with de novo coronary lesions].

Objective: To evaluate the five-year safety and efficacy of the second generation biodegradable polymer sirolimus-eluting stent (EXCROSSAL) in treating patients with de novo coronary artery diseases. Methods: Patients with coronary artery disease (CAD)who were implanted with EXTROSSAL stents in CREDIT Ⅱ and CREDIT Ⅲ study were included. CREDIT Ⅱ was a randomized trial, and CREDIT Ⅲ was a single-arm study. From November 2013 to December 2014, 833 CAD patients with de novo coronary lesions implanted with EXTROSSAL stents were selected from 33 centers in China. The primary outcome was 5-year target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction and clinically indicated target lesion revascularization. Secondary endpoints was patient-oriented composite endpoint (PoCE), including all-cause death, all myocardial infarction, or any revascularization within 5 years post stenting and stent thrombosis according to Academic Research Consortium's (ARC) definition. Kaplan Meier method was used to calculate the incidence of TLF and PoCE within 5 years after operation. Univariate Cox regression analysis was used to analyze the impacts of diabetes, small vessel disease (vessel diameter ≤ 2.74 mm), lesion length ≥ 16.7 mm and multivessel disease on the incidence of TLF within 5 years after operation. Results: A total of 833 patients were included in this study including 579 males (69.5%), the age was (59.3±9.1) years. And 832 (99.9%) patients completed 5-year clinical follow-up. The incidence of TLF and PoCE in the 5-year follow-up were 10.6%(86/811) and 15.5%(126/811), respectively. Stent thrombosis occurred in 1.0%(8/811) of patients. Univariate Cox regression analysis showed that vessel diameter ≤ 2.74 mm (HR=3.20,95%CI 1.90-5.39,P<0.001), lesion length ≥ 16.7 mm (HR=1.88,95%CI 1.18-2.99,P=0.007) and multivessel disease (HR=2.44,95%CI 1.60-3.72,P<0.001) were related factors of TLF within 5 years after operation. Conclusion: EXCROSSAL stent is effective and safe in treating CAD patients with de novo coronary lesions, with low incidence of TLF and PoCE within 5 years after operation.

Tunable electronic and optical properties of a BAs/As heterostructure by vertical strain and external electric field.

Based on the first-principles method, we investigated the electronic properties of a BAs/arsenene (As) van der Waals (vdW) heterostructure and found that it has an intrinsic type-II band alignment with a direct band gap of 0.25 eV, which favors the separation of photogenerated electrons and holes. The band gap can be effectively modulated by applying vertical strain and external electric field, displaying a large alteration in the band gap via the strain and experiencing an indirect-to-direct band gap transition. Moreover, the band gap of the heterostructure varies almost linearly with external electric field, and the semiconductor-to-metal transition can be realized in the presence of a strong electric field. The calculated band alignment and optical absorption reveal that the BAs/As heterostructure could present an excellent light-harvesting performance. The absorption strength can be tuned mainly by interlayer coupling, while external electric field shows clear regulating effects on the absorption strength and absorption edge.

[Application of artificial intelligence in prevention and control of COVID-19 in Guangzhou city].

Since the outbreak of COVID-19, it has spread rapidly throughout the country and even in the world. As a first tier city, Guangzhou is also the South Gate of China, with large population mobility and severe and complex prevention and control situation. Guangzhou CDC, together with Tencent and Alibaba Cloud, has made full use of its artificial intelligence technology to carry out a series of practices in case transmission chain analysis, close contact and other key personnel management, front-line staff prevention and control skills training and convenience services. Through the application of artificial intelligence in different scenarios, the difficulties and challenges in the prevention and control are solved, and the speed of epidemic prevention and control is increased.

[Contagiousness and secondary attack rate of 2019 novel coronavirus based on cluster epidemics of COVID-19 in Guangzhou].

Objective: To analyze the contagiousness and secondary attack rate of 2019 novel coronavirus in cluster epidemics in Guangzhou and provide evidence for the prevention and control of COVID-19. Methods: All the individuals identified to be infected with 2019-nCoV in Guangzhou, including confirmed cases and asymptomatic cases, were included and classified as imported cases and local cases. The first case of each cluster epidemic was defined as index case, and the number of subsequent infections was calculated to evaluate the contagiousness and secondary attack rate of 2019 novel coronavirus in the shortest incubation period of 1-3 days. Results: As of 18 February, 2020, a total of 349 cases of 2019-nCoV infection, including 339 confirmed cases (97.13%) and 10 asymptomatic cases (2.87%) were reported in Guangzhou. There were 68 clusters involving 217 2019-nCoV infection cases (210 confirmed cases and 7 asymptomatic cases). The median number of subsequent infections caused by an index case in a cluster epidemic was 3, among which 2 were confirmed cases and 1 was asymptomatic cases, respectively. The average number of contagiousness was 2.18 in shorted incubation period of 1-3 days (The average number of infected cases were 2.18 cases by the index case in a cluster epidemic), the average infection number in family members was 1.86, and the infection ratio of family member transmission was 85.32% (1.86/2.18). The secondary attack rate in close contacts with shortest incubation period of 1-3 days was 17.12%-18.99%, the secondary attack rate in family members was 46.11%-49.56%. Conclusions: The cluster epidemic of COVID-19 in Guangzhou mainly occurred in families, the contagiousness was high. It is necessary to strengthen the prevention and control to reduce the community transmission of COVID-19.

[Long-term efficacy of a second generation biodegradable polymer sirolimus-eluting stent (EXCEL2) in treating patients with de novo coronary artery diseases].

Objective: To evaluate the long-term efficacy of a second generation biodegradable polymer sirolimus-eluting stent (EXCEL2) in treating patients with de novo coronary artery diseases. Methods: CREDIT Ⅱ trial was a prospective, multicenter, randomized, controlled study, conducted at 15 Chinese cardiac centres from November 2013 to December 2014. In this analysis, eligible patients for coronary stenting (n=419) were randomized to receive either the EXCEL2 stent (n=208) or the EXCEL stent (n=211). The primary endpoint was target lesion failure (TLF) at 3 years after PCI defined as a composite endpoints of cardiac death, target vessel myocardial infarction (TVMI), or clinically indicated target lesion revascularization (CI-TLR). Secondary endpoints included patient-oriented composite endpoint (PoCE) including all-cause death, all MI, or any revascularization at 3 years and independent components, and stent thrombosis according to Academic Research Consortium's (ARC) definition. Results: Among 419 enrolled patients, 413 (98.6%) patients completed 3-year clinical follow-up. Compared with the EXCEL group, 3-year TLF (5.4%(11/204) vs. 11.5% (24/209), P=0.025) and PoCE (9.8% (20/204) vs. 20.1% (42/209), P=0.003) were significantly lower in the EXCEL2 group. The cumulative event rate of CI-TLR (2.0% (4/204) vs. 5.7% (12/209), P=0.042) and any revascularization (4.9% (10/204) vs. 14.4% (30/209), P=0.001) were statistically lower in the EXCEL2 group than in the EXCEL group. There were no significant difference between two groups in terms of all-cause death and all MI. Rates of stent thrombosis were low without significant difference between the two groups (EXCEL2 vs. EXCEL, 1.0% (2/204) vs. 2.9% (6/209), P=0.285). Conclusion: 3-year clinical follow-up results demonstrate that EXCEL2 stents are effective and safe in treating CAD patients with de novo coronary lesions.

[Clinical observation of LOP chemotherapy combined with radiotherapy in the treatment of early nasal NK/T cell lymphoma].

Objective:To investigate the efficacy and safety of LOP（asparaginase + vincristine + dexamethasone） chemotherapy combined with radiotherapy in patients with nasal NK/T cell lymphoma. Method:Sixty patients with nasal NK/T cell lymphoma admitted to our hospital from February 2012 to February 2016 were selected as the study subject. They were randomly divided into group A and group B, 30 cases in each group. All patients were treated with combined chemotherapy and IMRT（intensity modulated conformal radiotherapy）. The LOP regimen was used in group A and the CHOP（cyclophosphamide + pirarubicin + vincristine + dexamethasone） regimen was used in group B. The short-term efficacy, long-term efficacy and adverse reactions of the two groups were compared. Result:The clinical manifestations of 60 patients mainly included nasal obstruction（81.67%）, accompanied by fever, headache, nosebleed and runny nose. Forty-one patients（68.33%） had only one site of lesion, and 21 patients（35.00%） had multiple sites of lesions. In terms of total remission rate, it was significantly higher in group A than that in group B（93.33% vs. 66.67%, P<0.05）. In terms of adverse reactions, the incidence of bone marrow suppression, gastrointestinal reaction and low-protein reaction was significantly lower in group A than that in group B（P<0.05）. Three patients died in group A and 11 patients died in group B during the 3-year follow-up. The 3-year survival rate of group A was higher than that of group B（P<0.05）. Conclusion:Compared with CHOP+IMRT regimen, the LOP+IMRT regimen for nasal NK/T-cell lymphoma patients resulted in higher overall remission rate, survival rate and lower adverse reactions, so it is worth in clinical promotion.

[Effect of excimer laser coronary atherectomy in the interventional treatment of acute coronary syndrome].

Objective: To investigate the effect of excimer laser coronary atherectomy (ELCA) in the interventional treatment of acute coronary syndrome (ACS). Methods: This prospective study enrolled 31 patients with ACS who underwent ELCA treatment in our hospital from November 8, 2016 to December 13, 2017. The efficacy and complications of ELCA were observed, and patients were followed up for postoperative observation of major adverse cardiovascular and cerebrovascular events (including target vessel revascularization, stroke, stent thrombosis, coronary artery bypass grafting, and death). Results: The patients were aged (65.0±10.8) years old and 25 were males (80.6%).There were 5 cases (16.1%) ST-segment elevation myocardial infarction, 3 cases (9.7%) non-ST-segment elevation myocardial infarction, and 23 cases (74.2%) unstable angina in this cohort.There were 9 cases (29.0%) in-stent restenosis, 11 cases (35.5%) saphenous vein graft, 2 cases (6.5%) chronic total occlusive disease, and 4 cases (12.9%) calcification.Two patients with chronic complete occlusive disease and 1 patient with calcified lesion were examined by intravascular ultrasound (IVUS). The other lesions were not examined with IVUS and optical correlation tomography (OCT).The ELCA success rate was 100% (31/31) and the PCI success rate was 100% (31/31).Intraoperative use of 0.9 mm diameter catheters accounted for 38.7% (12/31), 1.7 mm diameter catheters accounted for 32.3% (10/31), and 1.4 mm diameter catheters accounted for 29.0% (9/31).One patient with ST-segment elevation myocardial infarction experienced no reflow of coronary artery during operation. The other 30 patients had no complications such as perforation, small dissection, large dissection, distal occlusion, slow blood flow and collateral occlusion. One cardiac death(3.2%) occurred during the postoperative follow-up of (6.4±1.9) months. Conclusion: Our preliminary study results indicate that the use of ELCA in the interventional therapy of ACS is safe and effective.