Effective photodegradation of rhodamine B and levofloxacin over CQDs modified BiOCl and BiOBr composite: Mechanism and toxicity assessment.

In this contribution, carbon quantum dots (CQDs) modified 3D-flower like BiOX (X = Cl, Br, I) photocatalyst were successfully prepared via a facile mechanical compounding method. The crystal structure, surface composition, morphologies, optical properties and photocatalytic activities were investigated in detail. The photocatalytic activity of the as-obtained photocatalyst were evaluated by degradation of rhodamine B (RhB) and Levofloxacin (LEV) under near IR-UV-vis light irradiation, the CQDs/BiOX composite displayed enhanced photocatalytic activity as compared with individual BiOX materials. The CQDs/BiOX composite had the outstanding light harvesting and electron transfer ability because of the ordered ultrathin nanosheet structure of the BiOX, the formation of metal Bi under photoinduction, and the synergistic effects between CQDs and pure BiOX. Antibacterial activity and effects on Rye seeds growth of the LEV degradation intermediate were also researched. Reactive-species-trapping experiments exhibited that h+ and O2- were the active reactive species during photodegradation process. This work provided an effective and simple strategy for designing QDs modified Bi-rich oxyhalides in organic pollutant containing wastewater treatment.

A survey of postpartum depression and health care needs among Chinese postpartum women during the pandemic of COVID-19.

BACKGROUND: The COVID-19 pandemic seriously endangers the public's mental health, especially to pregnant and postpartum women. But little is known about postpartum depression and health care needs among Chinese postpartum women. AIM: To investigate the status and risk factors of postpartum depression and health care needs among Chinese postpartum women during the COVID-19 pandemic. METHODS: In this cross-sectional study, 209 Chinese postpartum women were recruited from May to July 2020 by convenience sampling and assessed online with self-designed Maternal General Information Questionnaire, Edinburgh Postpartum Depression Scale (EPDS) and Chinese Version of the Perceived Stress Scale (CPSS). Descriptive statistics, chi-square test, independent samples t-test, one-way ANOVA, Pearson correlation and multiple linear regression were used for data analysis. RESULTS: With the EPDS cut-off value of 10, the incidence of postpartum depressive symptoms was 56.9%. Age, history of abortion and perceived stress were the influencing factors of postpartum depression (adjusted R2 = 0.432, F = 23.611, p < .001). The top three health care needs were infant rearing guidance (78.0%), maternal and infant protection guidance (60.3%) and dietary guidance (45.0%). The proportion of psychological rehabilitation guidance needs in the depressed group was significantly higher than that in the non-depressed group (34.5% vs. 20.0%, p < .05). CONCLUSIONS: Maternal postpartum depression in China was at a high level during the COVID-19 pandemic. Women aged 25-34, with a history of abortion and high stress levels were at higher risk for postpartum depression. Timely psychological counselling, intervention and COVID-19-related health education are in great need for postpartum women.

Correlation between self-perceived burden and self-management behavior in elderly stroke survivors: A longitudinal observational study.

The aim of this study was to assess the levels of self-perceived burden (SPB) and self-management behavior in elderly stroke survivors during the first 3 months after acute stroke, and to explore the correlation between them.A total of 203 consecutive hospitalized elderly patients diagnosed with stroke were recruited. Self-perceived Burden Scale and Stroke Self-management Scale in 1 month (T1) and 3 months (T2) post-stroke were assessed and compared.The score of SPB in elderly stroke survivors was 28.96 ±â€Š5.50 and 27.25 ±â€Š6.17 at T1 and T2, respectively. Stroke self-management scale scored 165.93 ±â€Š9.82 at T1 and 167.29 ±â€Š10.60 at T2. In the first 3 months post-stroke, the physical burden was dominant (T1 14.73 ±â€Š3.07, T2 14.40 ±â€Š3.13), and the behavior of stroke symptoms and signs monitoring (T1 27.58 ±â€Š6.56, T2 28.64 ±â€Š6.43) and rehabilitation exercise management (T1 21.40 ±â€Š3.28, T2 20.74 ±â€Š3.15) was the worst. SPB was negatively correlated with self-management behavior (T1 r = -.202, T2 r = -.511).Elderly stroke survivors experienced a medium level of SPB and self-management behavior in the first 3 months post-stroke. There is a positive relationship between reduced SPB and improved self-management behavior. Addressing the characteristics and correlations as well as development of targeted interventions for SPB decreasing is beneficial to improving self-management behavior for elderly survivors.

Monte Carlo studies on the interfacial properties and interfacial structures of ternary symmetric blends with gradient copolymers.

Using Monte Carlo simulation methods, the effects of the comonomer sequence distribution on the interfacial properties (including interfacial tension, interfacial thickness, saturated interfacial area per copolymer, and bending modulus) and interfacial structures (including chain conformations and comonomer distributions of the simulated copolymers at the interfaces) of a ternary symmetric blend containing two immiscible homopolymers and one gradient copolymer are investigated. We find that copolymers with a larger composition gradient width have a broader comonomer distribution along the interface normal, and hence more pronouncedly enlarge the interfacial thickness and reduce the interfacial tension. Furthermore, the counteraction effect, which arises from the tendency of heterogeneous segments in gradient copolymers to phase separate and enter their miscible phases to reduce the local enthalpy, decreases the stretching of copolymers along the interface normal direction. As a result, copolymers with a larger width of gradient composition can occupy a larger interfacial area and form softer monolayers at saturation and are more efficient in facilitating the formation of bicontinuous microemulsions. Additionally, chain length ratio, segregation strength, and interactions between homopolymers and copolymers can alter the interfacial character of gradient copolymers. There exists a strong coupling between the comonomer sequence distribution, chain conformation, and interfacial properties. Especially, bending modulus is mainly determined by the complicated interplay of interfacial copolymer density and interfacial chain conformation.

[Energy expenditure at physical activities of young and middle-aged adults in southern China].

OBJECTIVE: To investigate the energy expenditure at physical activities of young and middle-aged adults in southern China. METHODS: 64 healthy young and middle-aged adults living on light physical activity intensity were recruited by questionnaire and physical examination. A Cosmed k4b2 portable metabolic unit was used to measure the oxygen consumption (Vo2) and carbon dioxide production (Vco2) at a status of basic metabolism and during seven physical activities, including slow walking, brisk walking, walking upstairs, walking downstairs, watching TV, jogging and bicycling. The urinary nitrogen excreted in 24 hours was detected by a standard Kjeldahl method. Energy expenditure at physical activities was calculated by Weir equation. RESULTS: The energy expenditure (kJ x h(-1) x kg(-1)) at physical activities were 14.77 +/- 2.47 for slow walking, 22.18 +/- 3.68 for brisk walking, 41.34 +/- 7.32 for jogging, 18.41 +/- 3.89 for bicycling, 26.11 +/- 4.18 for walking upstairs, 13.68 +/- 2.89 for walking downstairs and 5.06 +/- 1.09 for watching TV. The energy expenditure of males at physical activities was higher than those of females (P < 0.05). CONCLUSION: There is a significant difference among energy expenditures at different physical activities; watching TV is a physical activity in light intensity; slow walking, brisk walking, walking upstairs, walking downstairs and bicycling are physical activities in moderate intensity, and jogging is a vigorous physical activity.