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Wastewater pollutants are a major threat to natural resources, with antibiotics and heavy metals being common water contaminants. By harnessing clean, renewable solar energy, photocatalysis facilitates the synergistic removal of heavy metals and antibiotics. In this paper, MXene was both a template and raw material, and MXene-derived oxide (TiO2) and SnIn4S8 Z-scheme composite materials were synthesized and characterized. The synergistic mode of photocatalytic reduction and oxidation leads to the enhanced utilization of e-/h+ pairs. The TiO2/SnIn4S8 exhibited a higher photocatalytic capacity for the simultaneous removal of tetracycline (TC) (20 mg·L-1) and Cr(VI) (15 mg·L-1). The main active substances of TC degradation and Cr(VI) reduction were identified via free radical scavengers and electron paramagnetic resonance (EPR). Additionally, the potential photocatalytic degradation route of TC was thoroughly elucidated through liquid chromatography-mass spectrometry (LC-MS).
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PURPOSE: To clarify the relationship between quality of sleep and pregnancy outcomes and to explore how sleep quality affects mood state in the first trimester of pregnancy. METHODS: This prospective cohort study enrolled pregnant women from June 2020 to June 2021. Maternal sleep conditions, daytime sleepiness, and mood state in the first trimester were assessed using four Chinese self-rating scales, namely, the Pittsburgh Sleep Quality Index (PSQI), the Sleep Hygiene Practice Scale (SHPS), Epworth Sleepiness Scale (ESS), and the abbreviated version of the Profile of Mood States (a-POMS). Participants were divided into an exposed group (PSQI score > 5, poor sleep quality group) and a non-exposed group (PSQI score ≤ 5, good sleep quality group). Maternal characteristics, pregnancy outcomes, and the relationship among sleep quality, sleepiness, and mood state were analyzed. Comparisons of sleep hygiene behavior variables between the two subgroups were also analyzed. RESULTS: A total of 2703 pregnant women were enrolled in the study. Poor sleep quality increased the probability of gestational diabetes mellitus (GDM) (1.573, 1.315-1.863), liver function damage (1.467, 1.021-2.107), preterm delivery (1.468, 1.077-2.002), mild sleepiness (1.612, 1.357-1.915), and excessive sleepiness (2.134, 1.686-2.701). Poor maternal sleep quality was significantly associated with the occurrence of preterm premature rupture of membranes (1.947, 1.168-3.243) and perinatal death (1.003, 1.000-1.006). Additionally, a significant positive correlation between the PSQI score and the total mood disturbance (TMD) score was revealed by Spearman's correlation analysis (r = 0.378, P < 0.01). Enter Regression analysis demonstrated that sleep quality (R2 = 0.390, P < 0.01) and sleepiness (R2 = 0.234, P < 0.01) exerted significant direct effects on mood state during pregnancy. Furthermore, Spearman's correlation analysis indicated a positive association between the PSQI score and the SHPS total score (r = 0.227, P < 0.01). CONCLUSIONS: Poor sleep quality is significantly associated with elevated rates of maternal mood disturbances, obstetric complications, and adverse outcomes in infants. The findings suggest that it may be useful to provide comprehensive sleep assessment and education on sleep hygiene during the early stages of pregnancy.
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Afeto , Complicações na Gravidez , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Qualidade do Sono , Humanos , Feminino , Gravidez , Adulto , Estudos Prospectivos , Afeto/fisiologia , Estudos de Coortes , Diabetes Gestacional/epidemiologiaRESUMO
PURPOSE: To explore the influence of sleep conditions and sleep hygiene behaviors in early pregnancy on gestational diabetes mellitus (GDM) development. METHODS: This 1:1 propensity-score matched study included 1,216 pregnant women divided into GDM and control groups based on diagnosis via the oral glucose tolerance test at 24-28 gestational weeks. Sleep conditions and hygiene behaviors were evaluated using structural questionnaires, including the Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, and Sleep Hygiene Practice Scale. Univariate and multivariate logistic regression analyses and Spearman's correlation were conducted to identify the associations. RESULTS: After adjusting for baseline clinical characteristics, women with GDM were more likely to have poor sleep quality (adjusted odds ratio [AOR] = 1.585, 95% confidence interval [CI]: 1.261-1.992) and higher scores for subjective sleep quality, latency, duration, efficiency, and sleep disturbances (all P < 0.01). Mild sleepiness (AOR = 1.311, 95% CI: 1.012-1.699) and worrying about not being able to fall asleep (AOR = 1.123, 95% CI: 1.005-1.255) were more likely to occur in the GDM group. Sleep quality and hygiene behaviors such as sleep-irrelevant activities, staying in bed after waking up, weekend catch-up sleep, and overeating before bedtime were significantly correlated with gestational diabetes variables. CONCLUSION: Poor sleep conditions and specific sleep hygiene behaviors in early pregnancy may be independent risk factors for GDM. This suggests that sleep assessment and behavior education can be used as new approaches for the early implementation of surveillance and prevention of GDM.
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INTRODUCTION: Cesarean scar defect (CSD) is a long-term outcome of cesarean section (CS) and associated with numerous gynecological and obstetric problems. Previous studies indicate that infection may be a risk factor for CSD. Adjunctive azithromycin was shown to reduce the risk of postoperative infection in patients undergoing non-elective primary cesarean delivery in labor or after the rupture of membranes compared with standard antibiotic prophylaxis. This study investigated the protective effect of adjunctive azithromycin in combination with single-dose cephalosporin against CSD in women undergoing non-elective cesarean delivery. MATERIAL AND METHODS: A randomized, double-blind, controlled clinical trial was conducted in a University hospital in Shanghai, China. A total of 242 women who underwent their first non-elective CS were randomly assigned to receive 1500 mg cefuroxime sodium plus 500 mg intravenous azithromycin (n = 121; experimental group) or 1500 mg cefuroxime sodium plus a placebo (n = 121; placebo group). The primary outcome was CSD prevalence, as determined by transvaginal ultrasound and saline infusion sonohysterography within 6 months of delivery. Secondary outcomes were changes in infectious indicators (eg hypersensitive C-reactive protein and procalcitonin), postoperative morbidity, and use of postoperative antibiotics. We also examined the operative procedure, pathogenic microorganism cultures, and fetal outcomes. Outcomes were compared between groups with the chi-squared test, Fisher's exact test, or Student's t test. RESULTS: Between May 2018 and May 2021, 121 women were randomized to each arm. Because the sonographic follow up was disrupted by the coronavirus disease 2019 pandemic and strict management policies, we merged the follow-up time points (6 weeks and 6 months) into a single time period (6 weeks to 6 months); 104 and 108 women in the experimental and placebo groups, respectively, completed the first sonographic follow up. CSD was diagnosed by sonography in 34/104 (32.7%) and 50/108 (46.3%) patients in the experimental and placebo groups, respectively (relative risk 0.71, 95% confidence interval 0.50-0.99; p = 0.043). Characteristics of CSD and short-term infection outcomes did not differ between groups. CONCLUSIONS: A single dose of intravenous 500 mg azithromycin adjunctive to single-dose cefuroxime prophylaxis significantly reduced the incidence of CSD in women undergoing non-elective CS.
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Tratamento Farmacológico da COVID-19 , Complicações Infecciosas na Gravidez , Antibioticoprofilaxia/efeitos adversos , Azitromicina/uso terapêutico , Cefuroxima/uso terapêutico , Cesárea/efeitos adversos , Cesárea/métodos , China , Cicatriz/epidemiologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , SódioRESUMO
BACKGROUND Since China has not yet constructed its own risk assessment model (RAM) for pregnancy-related venous thromboembolism (VTE), more and more hospitals use the RCOG RAM for VTE risk prediction. However, the RCOG RAM was established based on Western populations, and its applicability in China is still uncertain. Thus, we aimed to evaluate the validity of the RCOG RAM in predicting postpartum VTE in Chinese maternity. MATERIAL AND METHODS This retrospective case-control study was conducted at the International Peace Maternity and Child Health Hospital (IPMCHH) from June 2016 to June 2020. The VTE group consisted of 38 women with postpartum VTE. For each VTE patient, 4 women without VTE who gave birth on the same day were randomly selected as the control group (n=152). The receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) were used to evaluate the discrimination, accuracy, and validity of the RCOG RAM. Univariable analysis and multivariable logistic regression analysis were used to identify other related factors for postpartum VTE. RESULTS Compared with the low-risk group, the risk of VTE was 9.75-fold greater in the intermediate-risk group, and 90.00-fold greater in the high-risk group. The area under curve (AUC) of the model was 0.828 (95% CI: 0.762-0.894), with a score of 2 as its best cut-off value, which exactly matched the criterion recommended by the RCOG guidelines for pharmacological thromboprophylaxis. The calibration curves and DCA of the model also showed good accuracy. In addition to the factors included in the RCOG RAM, glucocorticoid therapy during pregnancy (adjusted OR=6.72, 95% CI: 1.56-28.91) and previous use of IUD (adjusted OR=7.11, 95% CI: 1.45-34.93) were associated with increased risk of postpartum VTE. CONCLUSIONS The RCOG RAM was found to be effective in predicting postpartum VTE, and has certain guiding significance for postpartum thromboprophylaxis in China.
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Tromboembolia Venosa/epidemiologia , Adulto , China/epidemiologia , Feminino , Humanos , Período Pós-Parto , Gravidez , Complicações Cardiovasculares na Gravidez , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
Enhanced capability of co-fermenting glucose and xylose at high temperature is highly desirable for yeast application in second-generation bioethanol production. Here, we obtained hybrid strains with improved glucose-xylose co-fermentation properties at high temperature by combining genome shuffling and adaptive evolution. Genome resequencing of these strains suggested predominantly inherited genetic information from one parental strain Spathaspora passalidarum SP rather than the other parental strain Saccharomyces cerevisiae ScY01, possibly due to that the CUG codon system of S. passalidarum might have systematically eliminated most of the functional proteins from S. cerevisiae through misfolding. Compared to SP, one-copy loss of a 146-kb fragment was found in the hybrid strain and regained after being evolved for a while, whereas one-copy loss of an 11-kb fragment was only found after being evolved for a longer time. Besides, the genes affected by nonsynonymous variants were also identified, especially the mutation S540F in the endoplasmic reticulum chaperon Kar2. Structural prediction indicated that S540F might change the substrate binding activity of Kar2, and thus play a role in preventing protein aggregation in yeast at high temperature. Our results illustrated genomic alterations during this process and revealed some genomic factors that might be involved to determine yeast thermotolerance.
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Dissacarídeos/metabolismo , Fermentação , Temperatura Alta , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomycetales/genética , Etanol/metabolismo , Evolução Molecular , Proteínas Fúngicas/genética , Engenharia Genética , Genoma Fúngico , Genômica , Glucose/metabolismo , Proteínas de Choque Térmico HSP70/genética , Mutação , TermotolerânciaRESUMO
OBJECTIVE: Radiofrequency thermocoagulation (RFTC) has emerged as an effective and safe treatment method for patients with refractory focal epilepsy, when stereo-electroencephalography (SEEG) is implanted. Although real-world research results are still limited, a considerable number of patients have shown favorable outcomes with this less invasive method. This study aims to describe the outcomes and predictive factors of SEEG-RFTC in real-world research. METHODS: A retrospective observational study was conducted on patients in the authors' epilepsy center. In total, 121 patients who underwent RFTC were included in the study. Post-RFTC outcomes were evaluated using the seizure-free rate and response rate (seizure frequency reduction more than 50%). Predictive factors influencing post-RFTC outcome were considered by comparing different variables. RESULTS: The mean follow-up period was 18.3 months. Eighty-two patients (67.8%) were responders and 54 (44.6%) were seizure free. In 36 patients with malformation of cortical development, the seizure-free rate and the response rate were 69.44% and 83.33%, respectively. In 20 patients with hippocampal sclerosis, 19 patients were responders and 14 (70%) patients were seizure free at the last follow-up. The MRI feature and etiology of epilepsy are correlated with the outcome. MR-positive is a predictive factor for seizure freedom (p < 0.01) and responders (p < 0.01). Other factors have no predictive value for post-RFTC outcome. INTERPRETATION: SEEG-RFTC is a safe procedure and yields favorable outcomes in numerous cases of focal DRE. The MRI feature and etiology of epilepsy are correlated with the seizure-free rate and response rate. And MRI positivity is the predictor for good RFTC outcome.
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Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Humanos , Masculino , Feminino , Adulto , Epilepsias Parciais/fisiopatologia , Epilepsia Resistente a Medicamentos/fisiopatologia , Epilepsia Resistente a Medicamentos/diagnóstico , Adulto Jovem , Estudos Retrospectivos , Adolescente , Pessoa de Meia-Idade , Criança , Eletrocoagulação , Eletroencefalografia , Seguimentos , Eletrocorticografia , Resultado do Tratamento , Pré-Escolar , Técnicas EstereotáxicasRESUMO
The electrochemical behaviors of CuCl, SnCl2 and a CuCl-SnCl2 mixture were investigated by cyclic voltammetry (CV) and square wave voltammetry (SWV). The reduction potentials of Cu(i) and Sn(ii) on CV curves are -0.49 and -0.36 V, respectively, while the reduction potentials of Cu(i)-Sn(ii) in the CuCl-SnCl2 mixture almost overlap. The co-chlorination reaction progress between CuCl-SnCl2 and Zr was also studied by monitoring the concentration changes of Cu(i), Sn(ii) and Zr(iv) ions in situ by CV, SWV and inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analyses. The results indicate that during the reaction, the concentration of Zr(iv) ions increases gradually, while those of Cu(i) and Sn(ii) decrease rapidly until they disappear. When the molar ratios of Cu(i) to Sn(ii) are 1 : 1 and 1 : 0.5, the reaction between Cu(i) and Zr is faster but cannot exceed twice that of Sn(ii) and Zr in a short time. When the theoretical product of ZrCl4 is a constant, and with the proportion of CuCl to SnCl2 decreasing from 1 : 0 to 0 : 1, the chlorination reaction time periods increase from 40 to 170 min. Chloride products such as Cu x Sn y , Sn x Zr y , and Cu x Zr y , are formed with different molar ratios. The coupling effect caused by the formation of alloys will promote the chlorination reaction when the ratios of CuCl to SnCl2 are 0.66 : 0.17 and 0.5 : 0.25. The results provide a theoretical basis for the electrolytic refinement of zirconium.
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Background: Esophageal cancer is a global health concern. Regularly updated data about the burden of esophageal cancer are essential for formulating specific public policies. We aimed to estimate the global, regional, and national burden and trends of esophageal cancer and its attributable risk factors from 1990 to 2019, by age, sex and socio-demographic index (SDI). Methods: Data about the incidence, death, disability-adjusted life-years (DALYs), and age-standardized rates were collected from Global Burden of Disease study 2019. Estimated annual percentage changes were used to quantify the temporal trends of age-standardized rates. Moreover, the risk factors attributable to esophageal cancer deaths were also presented. Results: There were 534,563 incident cases and 498,067 deaths in 2019, contributing to 11,666,017 DALYs. The absolute numbers of incidence, death, and DALYs had increased from 1990 to 2019, contrasting with declined changes in their corresponding age-standardized rates. The burden of esophageal cancer varied across different regions and countries, and the age-standardized rates were negative with SDI. Almost half of the esophageal cancer was concentrated in China. Males accounted for most of the burden of esophageal cancer, and the onset age tended to be older. The death of esophageal cancer was primarily attributable to smoking, followed by alcohol use, high body mass index, diet low in fruits and diet low in vegetables. Conclusion: The burden of esophageal cancer was heterogeneous across regions and countries by sex, age, and SDI, providing information for governments that may help to formulate more targeted policies.
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Neoplasias Esofágicas , Carga Global da Doença , Neoplasias Esofágicas/epidemiologia , Saúde Global , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Fatores de RiscoRESUMO
Background: Elevated intrapartum temperature has been widely proven to be associated with adverse clinical outcomes in both mothers and neonates. Histological chorioamnionitis (HCA), the inflammation of chorion and amniotic membranes, is commonly observed in those with elevated intrapartum temperature. Thus, we aimed to explore whether the combination of HCA would further affect the pregnancy outcomes in those with intrapartum temperature ≥ 37.5°C. Methods: This retrospective cohort study was conducted at the International Peace Maternity and Child Health Hospital (IPMCH), including all full-term women with intrapartum temperature ≥ 37.5°C from Jan 2017 to Jan 2019. Patients were divided in to HCA group or control group according to placental pathology results, and we used 1:1 propensity score matching (PSM) to reduce the effects of potential confounding factors between the two groups. Univariate and multivariable logistic regression were used to identify the association between HCA and different adverse maternal and neonatal outcomes. Results: We formed a propensity-score matched cohort containing 464 women in each group. Higher positive rate of mycoplasma (14.01% vs. 7.33%, p = 0.001) was found in the vaginal secretion culture of women in the HCA group. After adjusting for various baseline clinical characteristics, women with HCA were more likely to end their delivery by cesarean section (AOR = 1.55, 95% CI: 1.05-2.28), and puerperal morbidity (AOR = 2.77, 95% CI: 1.44-5.33) as well as prolonged hospitalization (AOR = 1.56, 95% CI: 1.12-2.17) were more likely to be observed in the HCA group. The existence of HCA might also be associated with neonatal sepsis (AOR = 2.83, 95% CI: 1.14-7.04) and NICU admission (AOR = 1.40, 95% CI: 1.04-1.87) in newborns. In the study on the impact of different stages of HCA, we found that both maternal and neonatal outcomes would not be affected by mild HCA (stage I), while HCA of stage III was associated with increased need for neonatal respiratory support and elevated likelihood of prolonged hospitalization in neonates. Conclusions: Elevated intrapartum temperature complicated by HCA might be related to the elevated occurrence of several adverse maternal and neonatal outcomes, except those with HCA of stage I. Advanced HCA stage correlated with a worse prognosis.
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The prognostic heterogeneity in patients with BRAF V600E metastatic colorectal cancer (mCRC) remains poorly defined. Real-world data of 93 BRAF V600E mCRC patients from Sun Yat-sen University Cancer Center were evaluated using the prognostic factors affecting overall survival (OS). Treatment of metastases served as an independent prognosticator, where curative locoregional interventions (LRIs) were associated with superior clinical outcomes (adjusted hazard ratio (HR): 0.46, 95% confidence interval (CI): 0.22-0.98; p = 0.044). The LRIs group showed an improved median OS of 49.4 months versus 18.3 months for the palliative treatments (PTs) group. The median OS of patients with colorectal liver metastasis (CRLM) was significantly prolonged after undergoing LRIs (42.4 vs. 23.7 months; HR: 0.11, 95% CI: 0.01-1.22; p = 0.030), and patients in the LRIs plus liver-limited or lung-limited metastasis (LLM) group benefited more than those in the LRIs plus non-LLM group when compared to the PTs group (LLM from LRIs vs. PTs, HR: 0.16, 95% CI: 0.04-0.68; p = 0.006. Non-LLM from LRIs vs. PTs, HR: 0.47, 95% CI: 0.21-1.05; p = 0.074). In conclusion, we confirmed the positive prognostic value of LRIs in BRAF V600E mCRC, particularly in patients with CRLM or LLM.
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Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Estudos de Coortes , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Modelos de Riscos ProporcionaisRESUMO
BACKGROUND: With the increasing trend of vaginal birth after caesarean delivery (VBAC), evaluation of the feasibility and safety of a second VBAC with grand multiparity is worth considering. Intrapartum uterine rupture is diagnosed in approximately one-fifth of all VBAC cases following successful vaginal delivery. To our knowledge, no report is available on the application of laparoscopy to repair postpartum uterine rupture after a successful second VBAC in China. CASE SUMMARY: A 31-year-old woman (gravida 5, para 2) at 39 wk and 5 d of gestation was admitted to the hospital in labour. After a successful VBAC and observation for approximately 13 h, the patient complained of progressive abdominal pain. Given the symptoms, signs, and auxiliary examination results, intraperitoneal bleeding was considered. Because the patient was stable and ultrasound imaging was the only method available to assess the possibility of rupture, we recommended laparoscopy to clarify the diagnosis and for prompt laparoscopic uterine repair or exploratory laparotomy if necessary. Operative findings included transverse uterine scar rupture at the lower uterine segment of approximately 5.0 cm in length and 800 mL of intraoperative pelvic haemoperitoneum. Finally, she successfully underwent laparoscopic repair of uterine rupture and recovered very well according to three-dimensional magnetic resonance imaging at 42 d postpartum. CONCLUSION: Routine postpartum intrauterine exploration is not beneficial to the mother and may even increase the risk of rupture. This case highlights a laparoscopic approach for repairing uterine rupture in the immediate postpartum period.
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INTRODUCTION: Perioperative infections may be considered predictors of caesarean scar defect (CSD), and multidose antibiotics have a protective effect against CSD. However, the ability of adjunctive azithromycin combined with cephalosporin to reduce the prevalence of CSD remains unclear. The planned study aims to clarify the protective effect of antibiotics against CSD and to assess the effectiveness of adjunctive azithromycin prophylaxis for CSD. METHODS AND ANALYSIS: This study is a double-blind, parallel-control randomised clinical trial that will be carried out at the International Peace Maternity and Child Health Hospital. A total of 220 eligible patients will be randomised (1:1) to receive either adjunctive azithromycin or single-dose cephalosporin 30 min before the incision. The evaluation criteria are the prevalence and characteristics of CSD as assessed by transvaginal ultrasound (TVU) and saline infusion sonohysterography (SIS) at 42 days, 6 months and 12 months after delivery. The primary outcome will be the prevalence of CSD, and the characteristics of CSD will be assessed by TVU and SIS 42 days after delivery; all other outcomes are secondary. ETHICS AND DISSEMINATION: This protocol received authorisation from the Medical Research Ethics Committee of International Peace Maternity and Child Health Hospital on 25 April 2018 (approval no. GKLW2017-84). The findings will be reported in peer-reviewed publications and presentations at international scientific meetings. TRIAL REGISTRATION NUMBER: ChiCTR-INR-17013272.
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Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Azitromicina/uso terapêutico , Cefalosporinas/uso terapêutico , Cesárea/efeitos adversos , Cicatriz/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Complicações Pós-Operatórias/prevenção & controle , GravidezRESUMO
The anodic dissolution behaviours of Cu, Zr and Cu-Zr alloy were analysed in LiCl-KCl at 500°C by anode polarization curve and potentiostatic polarization curve. The results show that the initial and fast-dissolving potentials of Cu are -0.50 and -0.29 V, and Zr are -1.0 and -0.88 V, respectively. But, in the Cu-Zr alloy, the initial and fast-dissolving potentials of Cu are -0.52 and -0.41 V, and Zr are -0.96 and -0.92 V, respectively. The potentials satisfy the selection dissolution principle that Zr in the alloy dissolves first, while Cu is left in the anode and is not oxidized. The passivation phenomenon of Zr is observed in the quick dissolution of Zr, while it is not observed in the Cu-Zr alloy. Moreover, from the above anodic dissolution results, potentiostatic electrolysis of Cu-Zr alloy was carried out at -0.8 V for 40 min, and the anodic dissolution mechanism and kinetics of Zr in Cu-Zr alloy were also discussed. In the initial stage, Zr dissolves as Zr4+ ions from the alloy surface and enters into the molten salt, leaving a Cu layer called 'dissolving layer' on the surface of the alloy. After that, another layer between the matrix and 'dissolving layer' called 'diffusion-dissolution layer' appears. Zr diffuses in the alloy matrix and dissolves as Zr4+ ions on the surface of the 'diffusion-dissolution layer' continuously, and Zr4+ ions diffuse through the 'dissolving layer' and enter into the molten salt finally. In addition, the factors affecting the dissolution of Cu-Zr alloy, such as time and potential, were also investigated. The dissolution loss increases with the increasing dissolution potential and time, while the dissolution rate increases with the increasing dissolution potential and declines with the prolonging dissolution time.
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Mig1 and Snf1 are two key regulatory factors involved in glucose repression of Saccharomyces cerevisiae. To enhance simultaneous utilization of glucose and xylose by engineered S. cerevisiae, single and double deletion strains of MIG1 and SNF1 were constructed. Combining shake flask fermentations and transcriptome analysis by RNA-Seq, the mechanism of Mig1 and Snf1 hierarchically regulating differentially expressed genes that might affect simultaneous utilization of glucose and xylose were elucidated. MIG1 deletion did not show any significant effect on co-utilization of mixed sugars. SNF1 deletion facilitated xylose consumption in mixed sugars as well as co-utilization of glucose and xylose, which might be due to that the SNF1 deletion resulted in the de-repression of some genes under nitrogen catabolite repression, thereby favorable to the utilization of nitrogen nutrient. Further deletion of MIG1 gene in the SNF1 deletion strain resulted in the de-repression of more genes under nitrogen catabolite repression and up-regulation of genes involved in carbon central metabolism. Compared with wild type strain, the MIG1 and SNF1 double deletion strain could co-utilize glucose and xylose, and accelerate ethanol accumulation, although this strain consumed glucose faster and xylose slower. Taken together, the MIG1 and SNF1 deletions resulted in up-regulation of genes under nitrogen catabolite repression, which could be beneficial to simultaneous utilization of glucose and xylose. Mig1 and Snf1 might be involved in the hierarchical regulatory network of genes under nitrogen catabolite repression. Dissection of this regulatory network could provide further insights to new targets for improving co-utilization of glucose and xylose.