Diethylenetriamine-functionalized reduced graphene oxide having more amino groups for methylene blue removal.

To obtain a high-performance amino-functionalized graphene, a new aminated graphene was prepared through a substitution reaction between chlorine-functionalized reduced graphene oxide and diethylenetriamine. The product exhibits high nitrogen content uniformly distributed in its sheets, with diethylenetriamine covalently attached to these sheets. The C-N bond in the product was certified by the Fourier transform infrared spectrum, which implies the successful attachment of diethylenetriamine to the graphene sheets. The average interlayer spacing is 0.42 nm. Diethylenetriamine features many more amino groups that act as ligands and spacers during adsorption and layer stacking processes. Compared with the adsorption capacities of reduced graphene oxide (77.1 mg g-1) and activated carbon (46.7 mg g-1), the product exhibits higher adsorption capacity (291.4 mg g-1). The adsorption process fits the quasi-first-order model and Langmuir model. Physical adsorption plays a primary role in the adsorption process. The amino group of the product easily reacts with other chemicals, making it a useful intermediate for other graphene materials.

In situ synthesis of a Bi2O3 quantum dot decorated BiOCl heterojunction with superior photocatalytic capability for organic dye and antibiotic removal.

As a decoration method, coupling a photocatalyst with semiconductor quantum dots has been proven to be an efficient strategy for enhanced photocatalytic performance. Herein, a novel BiOCl nanosheet decorated with Bi2O3 quantum dots (QDs) was first synthesized by a facile one-step in situ chemical deposition method at room temperature. The as-prepared materials were characterized by multiple means of analysis. The Bi2O3QDs with an average diameter of about 8.0 nm were uniformly embedded on the surface of BiOCl nanosheets. The obtained Bi2O3QDs/BiOCl exhibited significantly enhanced photocatalytic performance on the degradation of the rhodamine B and ciprofloxacin, which could be attributed to the band alignment, the photosensitization effect and the strong coupling between Bi2O3 and BiOCl. In addition, the dye photosensitization effect was demonstrated by the monochromatic photodegradation experiments. The radical trapping experiments and the ESR testing demonstrated the type II charge transfer route of the heterojunction. Finally, a reasonable photocatalytic mechanism based on the relative band positions was discussed to illustrate the photoreaction process. These findings provide a good choice for the design and potential application of BiOCl-based photocatalysts in water remediation.

Self-supporting photocatalyst of 2D Bi2O3 anchored on carbon paper for degradation pollutants.

Two-dimensional vertically aligned Bi2O3 nanosheets over carbon paper (CP) were prepared via an in situ growth approach. Bi2O3/CP exhibits a robust photocatalytic activity, as well as renewability and flexibility. With Rhodamine B and 2,4-dichlorophenol used as target pollutants, the rate constant of Bi2O3/CP was 3.72 × 10-3 min-1 and 6.93 × 10-3 min-1 under visible-light irradiation for 2 h, respectively. The improved activity was attributed to the synergistic effects of the hierarchical structure of Bi2O3 and the conductive substrate, CP; the former provided efficient catalytic sites for the pollutants and absorbed more of the light scattered among the nanosheets, while the latter is beneficial to the photogenerated electron transfer.

Robust photocatalytic activity of two-dimensional h-BN/Bi2O3 heterostructure quantum sheets.

Herein, defect intrinsic hexagonal boron nitride (h-BN) quantum sheets (QS) and bismuth oxide (Bi2O3) QS were prepared from bulk materials by ball milling and solvent stripping, respectively. The h-BN/Bi2O3 heterostructure was fabricated via a facile self-assembly method. The structure and performance of samples were systematically characterized. As expected, the layered h-BN QS is tightly coated on the surface of Bi2O3 QS in a face-to-face stacking structure and interconnected by strong interface interactions. The introduction of h-BN QS can significantly enhance the separation efficiency of the photogenerated carriers of h-BN/Bi2O3. The experimental results show that the photocatalytic activity of h-BN/Bi2O3 is markedly improved. The first-order reaction rate constant of the 3wt%-BN/Bi2O3 sample is 3.2 × 10-2 min-1, about 4.5 times that of Bi2O3 QS. By means of the active species capture test, it is found that the main oxidation species are holes (h+), followed by hydroxyl radicals (˙OH). Based on the surface charge transfer characteristics, the photogenerated carrier transfer and separation efficiency can be improved by coupling h-BN and a Bi2O3 semiconductor to the Schottky heterojunction, and the strong interaction between heterogeneous interfaces also enhances the surface catalytic reaction efficiency, which improves dramatically the photocatalytic performance.

Analytical Solution of Thermo-Mechanical Properties of Functionally Graded Materials by Asymptotic Homogenization Method.

In this work, a general mathematical model for functionally graded heterogeneous equilibrium boundary value problems is considered. A methodology to find the local problems and the effective properties of functionally graded materials (FGMs) with generalized periodicity is presented, using the asymptotic homogenization method (AHM). The present models consist of the matrix metal Mo and the reinforced phase ceramic ZrC, the constituent ratios and the property gradation profiles of which can be described by the designed volume fraction. Firstly, a new threshold segmentation method is proposed to construct the gradient structure of the FGMs, which lays the groundwork for the subsequent research on the properties of materials. Further, a study of FGMs varied along a certain direction and the influence of the varied constituents and graded structures in the behavior of heterogeneous structures are investigated by the AHM. Consequently, the closed-form formulas for the effective thermo-mechanical coupling tensors are obtained, based on the solutions of local problems of FGMs with the periodic boundary conditions. These formulas provide information for the understanding of the traditional homogenized structure, and the results also be verified the correctness by the Mori-Tanaka method and AHM numerical solution. The results show that the designed structure profiles have great influence on the effective properties of the present inhomogeneous heterogeneous models. This research will be of great reference significance for the future material optimization design.

Mediating Role of Mental Resilience between Sleep Quality and Mindfulness Level of Pregnant Women Screened by Prenatal Diagnosis.

OBJECTIVE: To explore the status quo of psychological resilience, mindfulness level, the sleep quality of pregnant women by Prenatal Diagnosis Screening, and the mediating effect of psychological resilience on sleep quality and mindfulness. METHODS: A survey of 298 pregnant women was conducted using the psychological resilience scale, Pittsburgh sleep quality index, and the concise version of the five-factor mindfulness scale. RESULTS: The total score of psychological resilience of pregnant women was (68.96 ± 17.27), mindfulness was (77.25 ± 12.65), the median of total sleep quality was 6, and the detection rate of sleep disorders was 31.9%. The sleep quality of pregnant women was negatively correlated with mindfulness level and psychological resilience (p < 0.01), and mindfulness level was positively associated with psychological resilience (p < 0.01). Bootstrap analysis showed that psychological resilience played an 14.1% mediating role between mindfulness and sleep quality. CONCLUSION: The psychological resilience of pregnant women is low, sleep quality is poor, and mindfulness is mild to moderate. Psychological resilience plays an important role in mediating between mindfulness level and sleep quality that suggests nursing staff should pay attention to and improve the psychological resilience of pregnant women screened by prenatal diagnosis to improve the mindfulness level and sleep quality of pregnant women screened by prenatal diagnosis.

A Meta-Analysis of Breastfeeding Effects for Infants With Neonatal Abstinence Syndrome.

BACKGROUND: Neonatal abstinence syndrome (NAS) rates have dramatically increased. Breastfeeding is a nonpharmacological intervention that may be beneficial, reducing NAS symptom severity and thus the need for and duration of pharmacological treatment and length of hospital stay. OBJECTIVES: Conduct meta-analysis to determine whether breastfeeding results in better outcomes for NAS infants. Variables included symptom severity, need for and duration of pharmacological treatment, and length of hospital stay. METHODS: PubMed, Scopus, Embase, and Cochrane Library were searched from 2000 to 2020, and comparative studies examining breastfeeding for NAS infants were extracted. Randomized trials and cohort studies were included. Data were extracted and evaluated with Review Manager Version 5.3. A random-effects model was used to pool discontinuous outcomes using risk ratio and 95% confidence intervals. Continuous outcomes were evaluated by mean differences and 95% confidence intervals. RESULTS: Across 11 studies, 6,375 neonates were included in the meta-analysis. Using a random-effects analysis, breastfeeding reduced initiation of pharmacological treatment, reduced duration of pharmacological treatment, and reduced length of stay. No differences were detected for severity of NAS symptoms. Most studies only reported one to two variables of interest. For most studies, these variables were not the primary study outcomes. All studies were found to be of low risk and good quality based on the Cochrane Risk Assessment Tools. Varying breastfeeding definitions limit generalizability. DISCUSSION: Breastfeeding is associated with decreased initiation and duration of pharmacological treatment and length of stay.

Efficacy of Intermittent Phototherapy versus Continuous Phototherapy for Treatment of Neonatal Hyperbilirubinaemia: A Systematic Review and Meta-analysis.

AIMS: We review the current literatures to determine whether intermittent phototherapy is more effective than continuous phototherapy in treating neonatal hyperbilirubinaemia. DESIGN: The systematic review is a systematic review and meta-analysis. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were used for reporting methods and results of synthesis with meta-analysis. Synthesis Without Meta-analysis (SWIM) guidelines were used for reporting methods and results of synthesis without meta-analysis. DATA SOURCE: Pubmed, Embase, Cochrane library, China National Knowledge Infrastructure, China Biology Medicine, VIP Database, and Wanfang Database. REVIEW METHODS: PICOS eligibility criteria were used to select original studies published from 1984 through 2019. Data were statistically extracted and evaluated using RevMan 5.3 software. RESULTS: A total of 416 records were identified through database searching. Four studies (three randomized studies and one retrospective study) meet the final inclusion criteria. Seven hundred and sixteen neonates were included in the meta-analysis. There was no difference in the treatment efficacy and total serum bilirubin (TSB), while there was a significant difference in phototherapy duration and side effects after treatment of intermittent phototherapy and continuous phototherapy for neonatal hyperbilirubinaemia. CONCLUSION: Intermittent phototherapy appeared to be as effective as continuous phototherapy for the treatment of neonatal hyperbilirubinaemia and is safer than continuous phototherapy. Healthcare organizations and health workers should choose intermittent phototherapy as the preferred therapy for neonatal hyperbilirubinaemia. IMPACT: Intermittent phototherapy is an effective, feasible, and safer treatment method for the infants with hyperbilirubinaemia in paediatric department. Healthcare organizations and health workers should choose intermittent phototherapy as the preferred therapy for neonatal hyperbilirubinaemia.

Dynamic evolution of electrochemical and biological features in microbial fuel cells upon chronic exposure to increasing oxytetracycline dosage.

Dynamic changes in power generation and electrochemical properties were compared between the control microbial fuel cells (C-MFC) and an oxytetracycline (OTC)-treated MFC (O-MFC) on days 84, 139, 174, 224, 295, 307 and 353. The results showed that a high concentration of OTC (>5 mg·L-1) could inhibit microbial activity and result in a decline of voltage output and power density compared with the same C-MFC. However, with the prolongation of incubation time, the inhibitory effect was gradually weakened. Electrochemical analyses demonstrated that long-term OTC acclimation reduced the ohmic and polarisation resistance of the anode, which was conducive to the recovery of electrochemical performance. More than 99% of 10 mg·L-1 OTC could be removed within 48 h, and the antibacterial activity of the MFC effluent on Escherichia coli DH5α was conclusively eliminated. High-throughput sequencing analysis revealed that the diversity and richness of the microbial community decreased significantly after long-term OTC enrichment. Acinetobacter, Petrimonas, Spirochaetaceae and Delftia were enriched and played a dominant role in C-MFC stability and power generation. The promotion by Cupriavidus, Geobacter and Stenotrophomonas in simultaneous OTC degradation and bioelectricity generation in the O-MFC was demonstrated.

Home-Based Phototherapy Versus Hospital-Based Phototherapy for Treatment of Neonatal Hyperbilirubinemia: A Systematic Review and Meta-Analysis.

Objective. Phototherapy devices have been found to be an effective method for treating neonatal hyperbilirubinemia. We reviewed the current literature to determine whether home-based phototherapy is more effective than hospital-based phototherapy for the treatment of neonatal hyperbilirubinemia. Method. PubMed, Scopus, Embase, Cochrane library, CBM, CNKI, and Wanfang Data were searched to collect the comparative study of home-based phototherapy versus hospital-based phototherapy for the treatment of neonatal hyperbilirubinemia. All studies were found to be of low risk based on Cochrane Collaborative Risk of Bias Tool. Data were statistically extracted and evaluated by RevMan 5.3 software. Result. A total of 259 neonates were included in the meta-analysis. Compared with hospital-based phototherapy, home-based phototherapy appeared more effective for the treatment of neonatal hyperbilirubinemia in reducing the rate of total serum bilirubin (standard mean difference = 0.32, 95% confidence interval = -0.22 to 0.86, P = .04); however, there was no significant difference in duration of phototherapy (standard mean difference = 0.59, 95% confidence interval = 0.28 to 0.90, P = .06) in the 2 groups. Conclusion. Home-based phototherapy was more effective than hospital-based phototherapy in treatment for neonatal hyperbilirubinemia; home-based phototherapy is an effective, feasible, safe, and alternative to hospital-based phototherapy for neonatal hyperbilirubinemia.

Modified dachengqi tang improves decreased gastrointestinal motility in postoperative esophageal cancer patients.

OBJECTIVE: To investigate the clinical effects of modified dachengqi tang (DCQT) on promoting gastrointestinal motility in post-operative esophageal cancer patients. METHODS: Sixty postoperative esophageal cancer patients were enrolled and randomly assigned to the modified treatment group or the control group (30 patients in each group). Patients in the treatment group were given DCQT made from decocted herbs and administered via nasojejunal tube at a dosage of 150 mL. Gastrointestinal motility was assessed by recording time for recovery of bowel sounds, flatus, defecation, and the total amount of gastric drainage during the first three postoperative days. Plasma motilin (MTL) and vasoactive intestinal peptide (VIP) were measured one hour before and three days after surgery. RESULTS: Compared with the control group, the times to first bowel sound, flatus, and defecation were significantly shorter and there was less gastric drainage in the treatment group (P < 0.01, P < 0.01, P < 0.01, and P < 0.05, respectively). In the treatment group, postoperative plasma MTL was significantly higher (P < 0.01) and VIP was significantly lower than those in the control group (P < 0.05). There was no difference found in either MTL or VIP from before to after operation in the treatment group (P > 0.05). MTL was significantly lower and VIP was higher postoperatively in the control group, compared to before surgery (P < 0.01). CONCLUSION: Modified DCQT effectively improved decreased gastrointestinal motility in postoperative esophageal cancer patients by increasing MTL and reducing VIP.