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Although Ti2AX has excellent mechanical properties of both metals and ceramics, there are few papers exploring the correlation between mechanics and thermodynamics simultaneously. In this paper, the structure properties, elastic anisotropies, thermodynamic and tensile properties of Ti2AX (A = Al and Ga, X = C and N) MAX phases are studied by first-principles calculations. The results show that these MAX phases have thermodynamical, dynamical, and mechanical stabilities. The calculated anisotropy indexes indicate that the MAX phases are anisotropic in elastic modulus. Ti-X chemical bonds possess covalent-ionic mixed nature. Moreover, the sound velocities and thermal conductivities of these Ti2AX MAX phases are also anisotropic. According to the tensile calculation, the tensile strength along the [110] direction is greater than that along the [001] direction, and fracture failure will occur in the [110] direction. [ABSTRACT FROM AUTHOR]

Objective: To explore the relationship between amniotic fluid and peripheral blood inflammatory factors and the pregnancy outcomes after emergency cervical cerclage, and to identify effective indicators for predicting adverse pregnancy outcomes after the procedure. Methods: A case-control study was conducted, including pregnant women who were hospitalized at Sun Yat-sen Memorial Hospital, from January 1, 2013, to July 31, 2019, and underwent emergency cervical cerclage due to cervical dilatation at gestational age between 16 and 28 weeks. A total of 85 pregnant women who underwent amniocentesis for the detection of amniotic fluid inflammatory factors during the perioperative period were included. Based on whether their baby was perinatal death, the participants were divided into the case group (28 cases with perinatal death) and the control group (57 cases with live births). Univariate logistic regression analysis was performed to identify risk factors associated with adverse pregnancy outcomes, followed by multivariate logistic regression analysis to establish a regression model and nomogram. Results: (1) The levels of tumor necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6, IL-8, IL-10 in the amniotic fluid during the perioperative period and postoperative serum C-reactive protein (CRP) were significantly higher in the case group compared to the control group (all P <0.05). The case group underwent emergency cervical cerclage at an earlier gestational age compared to the control group, and their cervical dilation was greater than that of the control group (all P <0.05). However, there were no significant differences in the white blood cell counts, neutrophil percentage, and the level of preoperative CRP in the peripheral blood of pregnant women during the perioperative period (all P >0.05). (2) Univariate logistic regression analysis showed that the levels of amniotic fluid WBC, TNF-α, IL-1β, IL-2 receptor (IL-2R), IL-6, IL-8, IL-10, postoperative CRP in the peripheral blood, gestational age at cerclage and cervical dilation were associated with adverse pregnancy outcomes (all P <0.05). Multivariate regression analysis indicated that only the levels of amniotic fluid WBC and TNF-α were independent risk factors for perinatal death. (3) Based on clinical practice, a multivariate logistic regression model was constructed including the levels of amniotic fluid TNF-α, WBC, gestational age at cervical cerclage, and cervical dilation. A nomogram and calibration curve were plotted, which suggested its good predictive value for adverse pregnancy outcomes. Conclusions: During the perioperative period of emergency cervical cerclage, the levels of amniotic fluid WBC, TNF-α, IL-1β, IL-2R, IL-6, IL-8, IL-10 are associated with adverse pregnancy outcomes, with amniotic fluid WBC and TNF-α showing the closest relationship. However, there is no significant correlation between maternal peripheral hemogram during the perioperative period and adverse pregnancy outcomes. A model constructed by amniotic fluid TNF-α, WBC, cervical cerclage gestational age, and cervical dilation has a good predictive effect on adverse pregnancy outcomes.

Outbreaks caused by highly industrialized food companies are characterized by cross-border, trans-regional, rapid and unpredictable, related to serious disease and economic burden. A cluster of cases with monophasic s almonella enterica serovar Typhimurium ST34 infection suspected to be associated with consumption of contaminated chocolate products have been reported in several Europe countries since December 2021. After retrospective investigations, the buttermilk circuit in the Belgian factory was suspected to be the point of origin of the contamination. This outbreak could provide a reference for the risk management of foodborne pathogens contamination in China. The objective of this paper was to summarize the process and characteristics of the outbreak of monophasic S. Typhimurium caused by contaminated chocolate products, analyze the characteristics of ST34 monophasic S. Typhimurium and the microbial management measures in the process of chocolate products, and systematically discuss the suggestions for the risk management of foodborne pathogens contamination and countermeasures for the rapid development of industrialization of food enterprises in China, in order to provide scientific and technological support for the prevention and control, prediction and early warning of sudden cases in China.

Objective: To explore the incidence and risk factors of postoperative surgical site infection (SSI) after colon cancer surgery. Methods: A retrospective case-control study was performed. Patients diagnosed with colon cancer who underwent radical surgery between January 2016 and May 2021 were included, and demographic characteristics, comorbidities, laboratory tests, surgical data and postoperative complications were extracted from the specialized prospective database at Department of General Surgery, Peking Union Medical College Hospital. Case exclusion criteria: (1) simultaneously multiple primary colon cancer; (2) segmental resection, subtotal colectomy, or total colectomy; (3) patients undergoing colostomy/ileostomy during the operation or in the state of colostomy/ileostomy before the operation; (4) patients receiving natural orifice specimen extraction surgery or transvaginal colon surgery; (5) patients with the history of colectomy; (6) emergency operation due to intestinal obstruction, perforation and acute bleeding; (7) intestinal diversion operation; (8) benign lesions confirmed by postoperative pathology; (9) patients not following the colorectal clinical pathway of our department for intestinal preparation and antibiotic application. Univariate analysis and multivariate analysis were used to determine the risk factors of SSI after colon cancer surgery. Results: A total of 1291 patients were enrolled in the study. 94.3% (1217/1291) of cases received laparoscopic surgery. The incidence of overall SSI was 5.3% (69/1291). According to tumor location, the incidence of SSI in the right colon, transverse colon, left colon and sigmoid colon was 8.6% (40/465), 5.2% (11/213), 7.1% (7/98) and 2.1% (11/515) respectively. According to resection range, the incidence of SSI after right hemicolectomy, transverse colectomy, left hemicolectomy and sigmoid colectomy was 8.2% (48/588), 4.5% (2/44), 4.8% (8 /167) and 2.2% (11/492) respectively. Univariate analysis showed that preoperative BUN≥7.14 mmol/L, tumor site, resection range, intestinal anastomotic approach, postoperative diarrhea, anastomotic leakage, postoperative pneumonia, and anastomotic technique were related to SSI (all P <0.05). Multivariate analysis revealed that anastomotic leakage (OR=22.074, 95%CI: 6.172-78.953, P <0.001), pneumonia (OR=4.100, 95%CI: 1.546-10.869, P =0.005), intracorporeal anastomosis (OR=5.288, 95%CI: 2.919-9.577, P <0.001) were independent risk factors of SSI. Subgroup analysis showed that in right hemicolectomy, the incidence of SSI in intracorporeal anastomosis was 19.8% (32/162), which was significantly higher than that in extracorporeal anastomosis (3.8%, 16/426, χ(2)=40.064, P <0.001). In transverse colectomy [5.0% (2/40) vs. 0, χ(2)=0.210, P =1.000], left hemicolectomy [5.4% (8/148) vs. 0, χ(2)=1.079, P =0.599] and sigmoid colectomy [2.1% (10/482) vs. 10.0% (1/10), χ(2)=2.815, P =0.204], no significant differences of SSI incidence were found between intracorporeal anastomosis and extracorporeal anastomosis (all P >0.05). Conclusions: The incidence of SSI increases with the resection range from sigmoid colectomy to right hemicolectomy. Intracorporeal anastomosis and postoperative anastomotic leakage are independent risk factors of SSI. Attentions should be paid to the possibility of postoperative pneumonia and actively effective treatment measures should be carried out.

Objective: To assess the taste function of healthy Chinese adults with the reliable whole-mouth taste test, and to analyze the correlation of taste function with age and gender. Methods: The clinical data of 584 participants reporting the normal sense of smell and taste from March 2019 to January 2020 in the Physical Examination Center of Beijing Anzhen Hospital were analyzed in the study, including 297 males and 287 females, aging (46.9±16.6) years. The subjects were divided into youth group (19-35 years old), middle aged group (36-50 years old), middle-elderly aged group (51-65 years old) and elderly group (66-80 years old). The taste test involved 5 tastants (sour, sweet, salty, umami and bitter) and 7 concentrations. The perception and recognition scores of five tastes were obtained through the whole-mouth taste test. SPSS 22.0 software was used for statistical analysis. Results: The intra-class correlation coefficients of the whole-mouth taste test were 0.751 to 0.828, which showed high test-retest reliability. The total score of perception and recognition of five tastes showed the significant negative correlation with age ( r value was -0.49 and -0.44, respectively, both P <0.001). Compared with the other two groups, taste function of middle-elderly aged and elderly group decreased significantly (all P <0.001). There was no significant difference in total perception scores and total recognition scores between youth and middle aged group (all P >0.05). The perception scores and recognition scores of sour, salty, umami, bitter and total scores in females were higher than those in males (all P <0.05), but there was no significant difference in perception scores and recognition scores for sweet between them ( P value was 0.584 and 0.223, respectively). Conclusions: The taste function is significantly negatively correlated with age. Except the sweet, females are more sensitive to the sour, salty, umami and bitter tastes than males.

Objective: To explore the effects of porcine acellular dermal matrix (ADM) combined with human epidermal stem cells (ESCs) on wound healing of full-thickness skin defect in nude mice. Methods: The morphology of porcine ADM was analyzed by photograph of digital camera, the cell residues in porcine ADM were observed by hematoxylin-eosin (HE) staining, the surface structure of porcine ADM was observed by scanning electron microscope, the secondary structure of porcine ADM was analyzed by infrared spectrometer, the porcine ADM particle size was analyzed by dynamic light scattering particle size analyzer, and the porcine ADM potential was analyzed by nano-particle size potentiometer. The morphology of porcine ADM was observed by inverted fluorescence microscope when it was placed in culture medium for 30 min, 1 d, and 5 d ( n =2). The porcine ADM was divided into 5 min group, 10 min group, 20 min group, 30 min group, 60 min group, and 120 min group according to the random number table (the same grouping method below) in static state at normal temperature for the corresponding time to calculate the water absorption by weighing method ( n =3). Swiss white mouse embryonic fibroblasts (Fbs) were divided into blank control group (culture medium only), and 50.0 g/L ADM extract group, 37.5 g/L ADM extract group, 25.0 g/L ADM extract group, 12.5 g/L ADM extract group, and 6.5 g/L ADM extract group which were added with the corresponding final concentrations of ADM extract respectively. At post culture hour (PCH) 24, 48, and 72, the cell survival rate was detected by cell counting kit 8 and the cytotoxicity was graded ( n =5). The erythrocytes of a 6-week-old male Sprague-Dawley male rat were divided into normal saline group, ultra-pure water group, and 5 mg/mL ADM extract group, 10 mg/mL ADM extract group, and 15 mg/mL ADM extract group which were treated with the corresponding final concentrations of porcine ADM extract respectively. After reaction for 3 h, the absorbance value of hemoglobin was detected by microplate reader to represent the blood compatibility of porcine ADM ( n =3). ESCs were isolated and cultured from the discarded prepuce of a 6-year-old healthy boy who was treated in the Department of Urology of the First Affiliated Hospital of Army Medical University (the Third Military Medical University) in July 2020, and then identified by flow cytometry. The porcine ADM particles of composite ESC (hereinafter referred to as ESC/ADM) were constructed by mixed culture. After 3 days of culture, the composite effect of ESC/ADM was observed by HE staining and laser scanning confocal microscope. Thirty-six 7-8-week-old male non-thymic nude mice were divided into phosphate buffer solution (PBS) alone group, ADM alone group, ESC alone group, and ESC/ADM group, with 9 mice in each group, and the wound model of full-thickness skin defect was established. Immediately after injury, the wounds were treated with the corresponding reagents at one time. On post injury day (PID) 1, 7, 11, and 15, the wound healing was observed and the wound healing rate was counted ( n =3). On PID 7, the epithelialization of wounds was observed by HE staining and the length of un-epithelialized wound was measured (with this and the following sample numbers of 4). On PID 11, the dermal area and collagen deposition of wounds were observed by Masson staining and the dermal area of wound section was calculated, the number of cells expressing CD49f, a specific marker of ESC, was calculated with immunofluorescence staining, the mRNA expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) in ESC after wound transplantation was detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction. Data were statistically analyzed with independent sample t test, one-way analysis of variance, analysis of variance for repeated measurement, and least significant difference t test. Results: The porcine ADM was white particles and composed of reticular structure, with no cells inside, disordered structure, and rough surface. The absorption peak of porcine ADM appeared at the wave numbers of 1 659, 1 549, and 1 239 cm -1 , respectively. The main particle size distribution of porcine ADM in solution was 500 to 700 nm, with negative charge on the surface. The morphology of porcine ADM in static state at 30 min and on 1 and 5 d was relatively stable. The water absorption of porcine ADM remained relatively high level in static state from 30 min to 120 min. The cytotoxicity of mouse embryonic Fbs in 6.5 g/L ADM extract group, 12.5 g/L ADM extract group, and 25.0 g/L ADM extract group was grade 1 at PCH 24, and the cytotoxicity of the other groups was 0 grade at each time point. After reaction for 3 h, the absorbance value of hemoglobin of erythrocytes in ultra-pure water group was significantly higher than the values in normal saline group and 15 mg/mL ADM extract group (with t values of 8.14 and 7.96, respectively, P <0.01). After 3 days of culture, the cells of the fourth passage showed pebble-like morphology, with low expression of CD71 and high expression of CD49f, which were identified as ESCs. There was ESC attachment and growth on porcine ADM particles. On PID 1, the wound sizes of nude mice were almost the same in PBS alone group, ADM alone group, ESC alone group, and ESC/ADM group. On PID 7, 11, and 15, the wound contraction of nude mice in each group was observed, especially in ADM alone group, ESC alone group, and ESC/ADM group. On PID 7, the wound healing rates of nude mice in ESC alone group and ESC/ADM group were significantly higher than the rate in PBS alone group (with t values of 2.83 and 4.72 respectively, P <0.05 or P <0.01). On PID 11, the wound healing rate of nude mice in ESC/ADM group was significantly higher than that in PBS alone group ( t =4.86, P <0.01). On PID 15, the wound healing rates of nude mice in ADM alone group, ESC alone group, and ESC/ADM group were significantly higher than the rate in PBS alone group (with t values of 2.71, 2.90, and 3.23 respectively, P <0.05). On PID 7, the length of un-epithelialized wound of nude mice in ADM alone group, ESC alone group, and ESC/ADM group was (816±85), (635±66), and (163±32) μm, respectively, which were significantly shorter than (1 199±43) μm in PBS alone group (with t values of 5.69, 10.19, and 27.54 respectively, P <0.01). On PID 11, the dermal areas of wound section of nude mice in ADM alone group, ESC alone group, and ESC/ADM group were significantly larger than the area in PBS alone group (with t values of 27.14, 5.29, and 15.90 respectively, P <0.01); the collagen production of nude mice in ADM alone group and ESC/ADM group was more obvious than that in PBS alone group, and the collagen production of nude mice in ESC alone group and PBS alone group was similar. On PID 11, in the wounds of nude mice in ESC alone group and ESC/ADM group, the cells with positive expression of CD49f were respectively 135±7 and 185±15, and the mRNA expressions of GAPDH were positive; while there were no expressions of CD49f nor mRNA of GAPDH in the wounds of nude mice in PBS alone group and ADM alone group. Conclusions: ESC/ADM particles can promote the wound healing of full-thickness skin defects in nude mice, which may be related to the improved survival rate of ESCs after transplantation and the promotion of dermal structure rearrangement and angiogenesis by ADM.

Objective: To observe the changes of olfactory function, intranasal trigeminal nerve function and taste function in patients with upper respiratory tract post-viral olfactory dysfunction (PVOD), and to explore the correlation of chemosensory function. Methods: The clinical data of 42 patients with PVOD who visited to the Olfactory and Taste Center of Otorhinolaryngology Head and Neck Surgery Department of Beijing Anzhen Hospital from January to December of 2019 were analyzed retrospectively, including 20 males and 22 females, aging (48.86±11.47) years (x¯). Twenty subjects in normal control group were selected according to the sex ratio of PVOD patients. Sniffin' Sticks olfactory tests were performed on the subjects, including threshold test (T), discrimination test (D) and identification test (I), and the sum of the above three test scores was the TDI value. At the same time, olfactory event-related potentials (oERPs), trigeminal event-related potentials (tERPs) and taste function test were performed. According to the taste function test, the patients were divided into normal gustation (NG) group and gustatory dysfunction (GD) group. The results of olfaction, taste and intranasal trigeminal nerve function tests were compared among different groups, and the correlation analysis was carried out. SPSS statistical software was used for statistical analysis. Results: GD was present in 14 (33.3%) of 42 PVOD patients with a course of PVOD of 5 (3, 6) months ( M ( Q 1 , Q 3 )). The gustatory function of patients with PVOD was related to gender ( r =0.565, P <0.001), smoking status ( r =-0.512, P =0.001), duration ( r =-0.357, P =0.020) and olfactory function (all P <0.05). The olfactory function of GD group was worse than that of NG group, and the differences of TDI value and T value between the two groups were statistically significant (10.25±4.58 vs 13.35±3.61, 1.54±0.66 vs 2.10±0.88, t value was 2.40 and 2.10 respectively, both P <0.05). The amplitudes of oERPs and tERPs were significantly lower in GD group than those in NG group (all P <0.05). Conclusion: In patients with PVOD, the subjective and objective olfactory function, intranasal trigeminal nerve function and taste function were decreased, and there was a correlation, suggesting that there was a synergistic effect between the chemosensory functions of PVOD patients.