Research on Dynamic Compressive Performance and Failure Mechanism Analysis of Concrete after High Temperature and Rapid Cooling

To investigate the dynamic compressive properties of concrete after high temperature and rapid cooling, an experimental study was carried out by considering five temperatures and four strain rates. The coupling effect of high temperature and strain rate on concrete damage morphology and mechanical parameters was comparatively analyzed. The main conclusions are as follows: the compressive damage morphology of concrete is affected by strain rate development trends of significant variability under different temperature conditions. As the strain rate increases, the compressive stress and elastic modulus of concrete are gradually increased. As the temperature increases, the increase in compressive stress is gradually reduced by the strain rate. For the temperatures of 20 °C and 800 °C, the increase in compressive stress by the strain rate is 38.69% and 7.78%, respectively. Meanwhile, SEM and CT scanning technology were applied to examine the mechanism of the effect of high temperature and strain rate on the mechanical properties of concrete from the microscopic perspective, and the corresponding constitutive model was proposed.     

Oral Health,Diabetes, and Inflammation: Effects of Oral Hygiene Behaviour

IntroductionThe aim of this research was to assess the association between inflammation and oral health and diabetes, as well as the mediating role of oral hygiene practice in this association.MethodsData were from the 2009–2010 National Health and Nutrition Examination Survey. The analytical sample consisted of 2,191 respondents aged 50 and older. Poor oral health was clinically defined by significant tooth loss (STL) and periodontal disease (PD). Diabetes mellitus (DM) was determined by glycemic levels. The outcome variable was serum C-reactive protein (CRP) level, dichotomised as ≥1 mg/dL (elevated CRP) vs <1 mg/dL (not elevated CRP). Two path models, one using STL and DM as the independent variable, the other using PD and DM as the independent variable, were estimated to assess the direct effects of having poor oral health and DM on elevated CRP and the mediating effects of dental flossing.ResultsIn path model 1, individuals having both STL and DM (adjusted odds ratio [AOR], 1.92; 95% confidence interval [CI], 1.30–2.82) or having STL alone (AOR, 2.30; 95% CI, 1.68–3.15) were more likely to have elevated CRP than those with neither STL nor DM; dental flossing (AOR, 0.92, 95% CI, 0.88–0.96) was associated with lower risk of elevated CRP. In path model 2, no significant association was found between having both PD and DM and elevated CRP; dental flossing (AOR, 0.91; 95% CI:, 0.86–0.94) was associated with lower risk of elevated CRP.ConclusionsFindings from this study highlight the importance of improving oral health and oral hygiene practice to mitigate inflammation. Further research is needed to assess the longer-term effects of reducing inflammation.Key words: Tooth loss, Periodontal disease, Diabetes, Inflammation     

糖尿病神经病变的评估和预防

糖尿病神经病变是糖尿病最常见和最复杂的并发症之一,可累及全身神经系统的任何部分,大约发生在近50%的糖尿病患者中.通常在1型糖尿病患者中,它出现较晚,而在2型糖尿病的早期就能发现.     

Transperineal pelvic drainage combined with lateral position to promote perineal wound healing after abdominoperineal resection: A prospective cohort trial

Background:For the rectal cancer <5 cm from anal margin, extralevator abdominoperineal resection (eAPR) has been accepted widely by surgeons. However, the rate of perineal infection following up eAPR is approximately 70%. We did the study with the aim of evaluating the effect and safety of transperineal pelvic drainage combined with lateral position (TPDLP) on perineal wound in patients undergoing eAPR.Methods:Patients were randomly assigned to N-TPDLP group (standard arm) or TPDLP group (intervention arm). In the standard arm, surgery was completed after abdominal drainage tube was placed in pelvic. Comparatively, an additional transperineal wound drainage tube was applied in the experimental arm. Postoperatively, patients of both 2 groups were informed not to sit to reduce perineal compression until the perineal wound healed. But lateral position was demanded in the intervention arm. The primary endpoint was the rate of uncomplicated perineal wound healing defined as a Southampton wound score of <2 at 30 days postoperatively. Patients were followed for 6 months.Results:In total, 60 patients were randomly assigned to standard arm (n = 31) and intervention arm (n = 29). The mean perineal wound healing time was 34.2 (standard deviation [SD] 10.9) days in TPDLP arm, which significantly differ from 56.4 (SD 34.1) in N-TPDLP arm (P = .001). At 30 days postoperatively, 3 (10%) of 29 patients undergoing TPDLP were classified into grade 4 according to Southampton wound score, however, 16 (52%) of 31 patients were classified into grade 4 in control arm, and significantly difference was observed between randomization groups (P = .001). What''s more, perineal wound pain was assessed at 30 days postoperatively, and it is discovered that the pain degree of patients in control arm was significantly more severe than the interventive arm (P = .015).Conclusion:In the present study, we found that TPDLP generated a favorable prognosis for perineal wounds with acceptable side-effects.     

Clinical application of metagenomic next‐generation sequencing technology in the diagnosis and treatment of pulmonary infection pathogens: A prospective single‐center study of 138 patients

IntroductionRapid and accurate pathogen identification is essential for the treatment of pneumonia. Metagenomic next‐generation sequencing (mNGS) is a newly developed technology to obtain microbial nucleic acid sequence information quickly, efficiently, and without bias.MethodsWe performed shotgun metagenomic next‐generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) for pathogen identification in pneumonia in a prospective study with 138 patients from a single center. We compared the results of mNGS with standard methods including culture, staining, and targeted PCR and evaluated the clinical applicability of mNGS.ResultsMost of the patients (128/138, 92.75%) were cured or improved. One patient (1/138, 0.72%) died because of acute gastrointestinal bleeding, and 9 patients (9/138, 6.52%) showed no improvement. mNGS identified more bacteria (53 versus 27), fewer fungi (8 versus 31), and more viruses (16 versus 1) than standard methods. In total, treatment in 34 out of 138 cases (24.64%) was adjusted and optimized because of mNGS results. Positive mNGS results contributed to a definitive diagnosis in 23 cases (16.67%), which helped guide treatment decision by either adjusting the antibiotics without de‐escalation or continuing the empirical treatment. mNGS also confirmed no active infection in 11 cases (7.97%) allowed for antibiotic de‐escalation.ConclusionThis prospective clinical study evaluated the clinical utility of mNGS for the diagnosis of pneumonia and showed that mNGS of BALF provides valuable information for effective treatment.     

Synergetic effect of photocatalysis and peroxymonosulfate activated by MFe2O4 (M = Co,Mn, or Zn) for enhanced photocatalytic activity under visible light irradiation

Nanosized MFe₂O₄ (M = Co, Mn, or Zn) photocatalysts were synthesized via a simple sol–gel method. MFe₂O₄ photocatalysts exhibited lower photocatalytic activity for the degradation of levofloxacin hydrochloride under visible light irradiation. For enhancement of photocatalytic activity, MFe₂O₄ was used to activate peroxymonosulfate and degrade levofloxacin hydrochloride under visible light irradiation. The influences of peroxymonosulfate dosage, levofloxacin hydrochloride concentration, pH value, and temperature on peroxymonosulfate activation to degrade levofloxacin hydrochloride were investigated in detail. The mechanism of activation of peroxymonosulfate by MFe₂O₄ was proposed and proved by radical quenching experiments, electron spin resonance analysis, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and transient photocurrent responses. The combined activation effects of photogenerated e⁻/h⁺ and transition metals on peroxymonosulfate to produce sulfate radical clearly enhanced the degradation efficiency.

The combined activation effects of photogenerated e⁻/h⁺, Fe, Co, Mn, and Zn on peroxymonosulfate to produce SO₄˙⁻ clearly enhanced the degradation efficiency.     

突发性聋临床分析

目的探讨突发性聋的治疗方法及预后因素。方法96例突发性聋病例采用川芎嗪、皮质类固醇激素、抗病毒药物为主的综合治疗,其中43例辅以高压氧治疗,分析患者年龄、初诊听力损失程度、听力曲线类型、治疗早晚、有无眩晕与预后的关系。结果痊愈25例,显效46例,痊愈率为26.04%,痊愈、显效率为73.96%;重度听力损失组,高压氧治疗组痊愈、显效率高于非高压氧治疗组(P<0.05);年龄18～40岁组,发病后10天内就诊组,轻、中度听力损失组,初诊听力曲线为平坦型和上升型组,无眩晕组疗效分别好于对照组(P<0.05)。结论年龄18～40岁,发病后10天内就诊,轻、中度听力损失组,初诊听力曲线为平坦型和上升型,无眩晕者预后好。     

头颈部游离组织瓣血管危象的预防和处理

目的探讨头颈部游离组织瓣术后血管危象的预防和处理方法。方法2003年3月～2008年4月我科96例游离组织瓣移植术后危象发生13例。回顾性分析危象发生时间,危象类型,皮瓣类型,吻合血管选择,血栓病理观察,处理过程和抢救成功率。结果13例中,保守处理成功5例。剩下8例中,动脉危象为1例,静脉危象6例,动静脉危象1例;前臂瓣2例,腹直肌3例,股外侧皮3例。首次发生危象时间分别在术后2小时～6天,平均34小时。8例中,4例系连续两次抢救,最终抢救成功4例,失败4例。结论术前认真选择适应证和规范的吻合技术是减少危象的关键;早期发现和掌握抢救技巧提高抢救成功率的关键。     

培哚普利对阵发性心房颤动导管射频消融术患者血清可溶型基质裂解素2和半乳糖凝聚素3水平的影响

目的研究培哚普利对阵发性心房颤动(PAF)导管射频消融术患者血清可溶型基质裂解素2(sST2)、半乳糖凝聚素3(galectin-3)水平的影响。方法选取2018年1月至2020年1月重庆医科大学附属第三医院收治的112例PAF导管射频消融术患者,随机数字表法分为试验组(培哚普利联合常规治疗方案)和对照组(常规治疗方案)各56例。比较两组治疗前及治疗3个月后心功能指标[左心房内径(LAD)、左室射血分数(LVEF)]、炎症因子[超敏C反应蛋白(hs-CRP)、血管紧张素Ⅱ(AngⅡ)]和疾病相关因子(sST2、galectin-3),比较两组复发情况及不良反应发生情况。结果治疗3个月后,试验组LAD、hs-CRP、AngⅡ、sST2、galectin-3水平明显低于治疗前及同期对照组,LVEF水平明显高于治疗前及同期对照组(P<0.05)。试验组早、晚期复发率均明显低于对照组(P<0.05)。两组恶心、呕吐、咳嗽、心脏压塞发生情况比较,差异无统计学意义(P>0.05)。结论培哚普利能够改善PAF导管射频消融术患者心功能,降低血清炎性因子、疾病相关因子水平及术后复发率。