Photocatalytic Degradation of Malachite Green by Titanium Dioxide/Covalent Organic Framework Composite: Characterization, Performance and Mechanism.

In this paper, a titanium dioxide/covalent organic framework (TiO2/COF) composite was prepared and its photocatalytic removal of dye was investigated. Using tetrabutyl titanate as a titanium source, TiO2 nanomaterial was prepared by sol-gel method. In the presence of TiO2, TiO2/COF core-shell composite was prepared by solvothermal synthesis using melamine and 1,4-phthalaldehyde as ligands. The prepared materials are characterized by SEM, TEM, XPS, XRD, TG, FTIR, BET, EPR, PL, and UV-Vis-DRS techniques. Using malachite green as a model of dye wastewater, the photocatalytic degradation performance of TiO2/COF composites was investigated under the irradiation of ultraviolet light. The results show that the modification of COF significantly improves the photocatalytic efficiency of TiO2, the degradation rate increases from 69.77 % to 93.64 %, and the reaction rate constant of the first-order kinetic equation is increased from 0.0078 min-1 to 0.0192 min-1. Based on the free radical capture experiment, the photocatalytic degradation mechanism of TiO2/COF was discussed, and the feasibility of its photocatalytic degradation of malachite green was theoretically clarified. Accordingly, a simple and practical method for photocatalytic degradation of malachite green was constructed, which has potential application value in the degradation of dye wastewater.

Determination of Pb2+ by Colorimetric Method Based on Catalytic Amplification of Ag Nanoparticles Supported by Covalent Organic Frameworks.

In this paper, covalent organic frameworks (COFs) are prepared by solvothermal synthesis using 1,3,5-benzenetricarboxaldehyde and benzidine as ligands. Then, using COFs as a template, AgCOFs with high catalytic activity is prepared by in situ loading silver nanoparticles (AgNC) on the surface of COFs by sodium borohydride reduction method. AgCOFs are characterized by TEM, SEM, FTIR and XRD. At the same time, the catalytic ability of AgCOFs for trisodium citrate-AgNO3 nanosilver reaction is studied. The results show that AgCOFs can catalyze the reaction of trisodium citrate-AgNO3 to generate silver nanoparticles (AgNPs). The solution color of the system gradually changes from colorless to yellow, and the absorbance value increases. Based on the catalytic reaction of AgCOFs and the regulation effect of nucleic acid aptamer reaction on AgCOFs, a new "on-off-on" colorimetric analysis platform is constructed and applied to the detection of trace Pb2+ in water samples. This analytical platform is simple, sensitive and selective. Finally, the catalytic mechanism of the system is discussed to verify the feasibility of constructing a colorimetric analysis platform.

Poor preoperative sleep quality is a risk factor for severe postoperative pain after breast cancer surgery: A prospective cohort study.

The aim of this study was to assess the effect of preoperative sleep quality on acute postoperative pain in breast cancer patients.The Pittsburgh Sleep Quality Index questionnaire (PSQI) was used to assess the overall sleep status of women scheduled for unilateral modified radical mastectomy in the past month. Based on the responses, patients were allocated to good sleep group or poor sleep group. Postoperatively, acute pain was assessed using the numerical rating score in the first 24 hours; in addition, the requirement of analgesics and the incidence of postoperative complications were recorded.A total of 108 breast surgery patients were enrolled. Based on the PSQI results, 55 (51%) patients were allocated to poor sleep group and 53 (49%) to good sleep group. Pain scores were similar in the 2 groups at the end of surgery (P = .589); however, poor sleep group reported higher postoperative pain scores than the good sleep group at 2 (P = .002), 6 (P < .001), 12 (P < .001), and 24 (P = .002) hours after surgery. The incidence of severe pain in the poor sleep group was higher than that in the good sleep group (27% vs 8%, P = .018), and the ratio of participants who required rescued analgesics was greater in the poor sleep group (52% vs 22%, P = .002). In addition, patients with poor sleep quality had more postoperative complications and longer hospital stay.In this study, breast cancer patients with poor preoperative sleep quality reported more severe postoperative pain, required more analgesics, experienced more complications, and had longer hospital stay.

[Dietary exposure assessment of antimony to inhabitants around mine contaminated areas in Nandan County in 2013-2014].

OBJECTIVE: To investigate the contents of antimony in Nandan food, and to research the effects of dietary pathways that mining surrounding usual's heavy metal intake due to mining activities. METHODS: Based on the data from weighing method and chemical analysis method, the dietary exposure level of antimony in Nandan was calculated, and the safety of antimony intake was evaluated by the TDI established by WHO. RESULTS: A total of 864 samples from 14 food categories were analyzed. The total detection rate was 97. 2%. And antimony concentrations in food ranged from not detected to 1. 750 µg/g, with median and geometric means of 0. 007 and 0. 008 µg/g, respectively. Dietary intakes of Sb by inhabitants in Nandan were below the TDI. The mainresource of antimony was meat which contributed 64. 4% and 61. 2% of the exposure. Antimony exposure to the human health risk assessmentresult show that, through diet of antimony intake, it would not cause obvious health risk to the local resident. However, the mining residents higher than the contrast areas residents, and male are apparently higher than those in female. CONCLUSION: The dietary of Sb exposure level was safe in general. However, the meat had a high risk to the residents.

Effects of Intraoperative Dexmedetomidine on Postoperative Pain in Highly Nicotine-Dependent Patients After Thoracic Surgery: A Prospective, Randomized, Controlled Trial.

To investigate the effects of intraoperative dexmedetomidine on pain in highly nicotine-dependent patients after thoracic surgery.Highly nicotine-dependent men underwent thoracic surgery and received postoperative patient-controlled intravenous analgesia with sufentanil. In dexmedetomidine group (experimental group, n = 46), dexmedetomidine was given at a loading dose of 1 µg/kg for 10 minutes, followed by continuous infusion at 0.5 µg/kg/h until 30 minutes before the end of surgery. The saline group (control group, n = 48) received the same volume of saline. General anesthesia was administered via a combination of inhalation and intravenous anesthetics. If necessary, patients were administered a loading dose of sufentanil by an anesthesiologist immediately after surgery (0 hours). Patient-controlled analgesia was started when the patient's resting numerical rating scale (NRS) score was less than 4. Resting and coughing NRS scores and sufentanil dosage were recorded 0, 1, 4 hours, and every 4 hours until 48 hours after surgery. Dosages of other rescue analgesics were converted to the sufentanil dosage. Surgical data, adverse effects, and degree of satisfaction were obtained.Cumulative sufentanil dosage, resting NRS, and coughing NRS in the first 24 hours after surgery and heart rate were lower in the experimental compared with the control group (P <0.05). No patient experienced sedation or respiratory depression. Frequency of nausea and vomiting and degree of satisfaction were similar in both groups.Intraoperative dexmedetomidine was associated with reduced resting and coughing NRS scores and a sufentanil-sparing effect during the first 24 hours after thoracic surgery.

[Characteristics of Heavy Metal Contents in Human Hairs of Mine Contaminated Areas in Nandan County].

Nandan county is usually called "land of nonferrous metals". In order to discuss the impact of mining activities on the health of inhabitants in Nandan county, 200 human hair samples were collected from 4 villages (Liuzhai is a uncontaminated contrast areas, Chehe, Dachang and Zhanglao are contaminated areas) of Nandan and analyzed for contents of As, Sb, Cd, Pb, Cu and Zn. The results showed that the average contents of As, Sb, Cd and Pb were 1.260, 2.161, 2.466 and 20.92 µg·g-1 in the human hair samples from contaminated areas. They were 4.0, 20, 2.1 and 1.9 times higher than those in the contrast areas, and the Sb contents in human hair of Chehe and Dachang were higher than the recommended normal range. The contents of human hair Zn showed a negative correlation with the age of people (P<0.05), and contents of human hair Cd and Pb showed a weak negative correlation with the age of people in contaminated areas (P<0.1). The independent-samples t-test showed that Cd contents in male hair were apparently higher than those in female hair (P<0.05), however, Cu and Zn contents in female hair were apparently higher than those in male hair (P<0.05), in the contaminated areas. There were positive correlations between As and Sb, Cd and Pb, as well as As and Cd (P<0.01), while other elements showed no significant correlation between pairs. It was therefore concluded that contamination from the mining activities has exposed a serious threat to human health in the mine contaminated areas in Nandan county.

Surgical cooperation during implantation of a Boston type-I keratoprosthesis.

This study was designed to summarize the key points of surgical cooperation involving penetrating corneal transplantation combined with implantation of keratoprosthesis. Preoperative preparation and intraoperative procedures were fully implemented to ensure cooperation with the physicians, to observe the the severity of the disease, and to guarantee the success of the surgery.

Increased pain in response to mechanical or thermal stimulation in a rat model of incision-induced pain with nicotine dependence and withdrawal.

The aim of this study was to observe the changes in mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) in a rat model of incisional pain with nicotine dependence and withdrawal. Twelve Wistar rats were randomly divided into a control and a withdrawal group, with 6 rats per group. In the control group, the rats were raised in normal conditions for 7 days without any treatment. A model of plantar incisional pain was established in the right lower extremity and changes in the plantar MWT and TWL of the healthy and operative sides were observed for 7 successive days. In the withdrawal group, the rats were raised in normal conditions and treated with a subcutaneous injection of pure nicotine (3 mg/kg), 3 times each day for 7 days. The model of plantar incisional pain in the right lower extremity was established, and changes in bilateral plantar MWT and TWL were observed for 7 days. The operative side plantar MWT and TWL in the withdrawal group were significantly lower than those in the control group on postoperative days 1-7, respectively (P<0.05). Compared with the healthy side in the control group, the healthy plantar MWT was significantly reduced on postoperative days 1-7 (P<0.05) and TWL was significantly decreased in postoperative days 1-6 (P<0.05) in the withdrawal group. The pain sensitivity to mechanical and thermal stimulation significantly increased in the rat model of incisional pain with nicotine dependence and withdrawal. This is consistent with the clinical increase of postoperative pain observed in patients after quitting smoking.