Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters










Publication year range
1.
J Colloid Interface Sci ; 663: 632-643, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38430833

ABSTRACT

Photocatalysts can absorb light and activate molecular O2 under mild conditions, but the generation of unsuitable reactive oxygen species often limits their use in synthesizing fine chemicals. To address this issue, we disperse 1 wt% copper on tungsten trioxide (WO3) support to create an efficient catalyst for selective oxidative coupling of aromatic amines to imines under sunlight irradiation at room temperature. Copper consists of a metallic copper core and an oxide shell. Experimental and density functional theory calculations have confirmed that Cu2O is the primary activation site. Under λ < 475 nm, the light excites electrons of the valence bands in Cu2O and WO3, which activate O2 to superoxide radical •O2-. Then rapidly transforms into oxygen adatoms (•O) and oxygen anion radicals (•O-) species on the surface of Cu2O. Simultaneously, it is captured by holes in the WO3 valence band to generate singlet oxygen (1O2). •O bind to 1O2 promoting the coupling reaction of amines. When λ > 475 nm, intense light absorption due to the localized surface plasmon resonance excites numerous electrons in Cu to promote the oxidative coupling with the adsorbed O2. This study presents a promising approach towards the design of high-performance photocatalysts for solar energy conversion and environmentally-friendly oxidative organic synthesis.

2.
World J Clin Cases ; 11(29): 7162-7169, 2023 Oct 16.
Article in English | MEDLINE | ID: mdl-37946757

ABSTRACT

BACKGROUND: Primary aortoduodenal fistula is a rare cause of gastrointestinal (GI) bleeding consisting of abnormal channels between the aorta and GI tract without previous vascular intervention that results in massive intraluminal hemorrhage. CASE SUMMARY: A 67-year-old man was hospitalized for coffee ground vomiting, tarry stools, and colic abdominal pain. He was repeatedly admitted for active GI bleeding and hypovolemic shock. Intermittent and spontaneously stopped bleeders were undetectable on multiple GI endoscopy, angiography, computed tomography angiography (CTA), capsule endoscopy, and 99mTc-labeled red blood cell (RBC) scans. The patient received supportive treatment and was discharged without signs of rebleeding. Thereafter, he was re-admitted for bleeder identification. Repeated CTA after a bleed revealed a small aortic aneurysm at the renal level contacting the fourth portion of the duodenum. A 99mTc-labeled RBC single-photon emission CT (SPECT)/CT scan performed during bleeding symptoms revealed active bleeding at the duodenal level. According to his clinical symptoms (intermittent massive GI bleeding with hypovolemic shock, dizziness, dark red stool, and bloody vomitus) and the abdominal CTA and 99mTc-labeled RBC SPECT/CT results, we suspected a small aneurysm and an aortoduodenal fistula. Subsequent duodenal excision and duodenojejunal anastomosis were performed. A 7-mm saccular aneurysm arising from the anterior wall of the abdominal aorta near the left renal artery was identified. Percutaneous intravascular stenting of the abdominal aorta was performed and his symptoms improved. CONCLUSION: Our findings suggest that 99mTc-labeled RBC SPECT/CT scanning can aid the diagnosis of a rare cause of active GI bleeding.

3.
Molecules ; 28(12)2023 Jun 13.
Article in English | MEDLINE | ID: mdl-37375295

ABSTRACT

Surface oxygen vacancy (OV) plays a pivotal role in the activation of molecular oxygen and separation of electrons and holes in photocatalysis. Herein, carbonaceous materials-modified MoO2 nanospheres with abundant surface OVs (MoO2/C-OV) were successfully synthesized via glucose hydrothermal processes. In situ introduction of carbonaceous materials triggered a reconstruction of the MoO2 surface, which introduced abundant surface OVs on the MoO2/C composites. The surface oxygen vacancies on the obtained MoO2/C-OV were confirmed via electron spin resonance spectroscopy (ESR) and X-ray photoelectron spectroscopy (XPS). The surface OVs and carbonaceous materials boosted the activation of molecular oxygen to singlet oxygen (1O2) and superoxide anion radical (•O2-) in selectively photocatalytic oxidation of benzylamine to imine. The conversion of benzylamine was 10 times that of pristine MoO2 nanospheres with a high selectivity under visible light irradiation at 1 atm air pressure. These results open an avenue to modify Mo-based materials for visible light-driven photocatalysis.

4.
Brain Sci ; 13(2)2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36831840

ABSTRACT

The visceral adiposity index (VAI) is related to the occurrence of various cardiometabolic diseases, atherosclerosis, and stroke. However, few studies have analyzed the impact on the short-term prognosis of stroke. We assessed the effect of VAI on short-term prognoses in patients with acute ischemic stroke through a retrospective cohort study of 225 patients with acute stroke who were admitted to the neurological intensive care unit of our hospital. We collected metabolic indicators (blood pressure, fasting glucose, lipids), National Institutes of Health Stroke Scale (NIHSS) scores, symptomatic intracranial hemorrhage, and other disease evaluation indicators on 197 patients who were screened for inclusion. VAI was calculated by using baseline data (sex, height, weight, waist circumference (WC)). We assessed functional recovery according to modified Rankin scale scores after 90 days. The receiver operating characteristic (ROC) curve was used to calculate the VAI cutoff value that affects short-term outcomes. A nomogram that can predict the risk of short-term mortality in patients with acute ischemic stroke was drawn. In total, 28 patients died within 90 days. Those patients had higher VAI (p = 0.000), higher triglyceride (TG) (p = 0.020) and NIHSS scores (p = 0.000), and lower high-density lipoprotein cholesterol (HDL-C) (p = 0.000) than patients who survived. VAI had higher predictive value of short-term mortality than did body mass index (BMI), body fat mass index (BFMI), and WC. VAI and NIHSS scores were independent risk factors for the short-term mortality of patients with stroke. Patients with a VAI > 2.355 had a higher risk of short-term mortality. VAI has a predictive value higher than that of traditional metabolic indicators such as BMI, BFMI, and WC. The nomogram, composed of NIHSS, VAI, HDL-C, and TG, may predict the short-term mortality of cerebral infarction patients.

5.
Article in English | MEDLINE | ID: mdl-36498195

ABSTRACT

BACKGROUND: School bullying is a major public health problem with a large impact on children's health. There is an increasing number of cases of school bullying reported in China. Studies have shown that the health consequences of different ways of responding to school bullying may be quite different and that psychological resilience is also closely related to aggressive behaviors. However, there has been little research on whether individuals with different psychological resilience levels respond differently. OBJECTIVE: To explore the relationship between responses to school bullying and psychological resilience, which may provide new ideas and strategies to better prevent and intervene in school bullying. METHODS: A random sample of 5425 primary school students aged 7-14 years were recruited in Luzhou, China. All students completed a questionnaire anonymously. The statistical significance of differences between groups was tested using the χ2 test or t test. Binary logistic regression was conducted to explore the relationship between responses and psychological resilience. RESULTS: Over two-thirds of primary school students in this study reported experiencing bullying in the past year. The rate of positive responses among victims was 69.10% (2596/3757, 95% CI: 67.62~70.58%). There was a positive relationship between psychological resilience and positive responses. This relationship was observed for all victims (OR = 1.605, 95% CI: 1.254~2.055), especially male victims (OR = 2.300, 95% CI: 1.624~3.259). CONCLUSIONS: There was a positive relationship between primary school bullying responses and psychological resilience among victims, with differences by sex. Therefore, increasing students' level of psychological resilience, possibly by improving their responses, is important for preventing school bullying. Meanwhile, effective interventions for school bullying should be developed from multiple perspectives, particularly sex, bullying roles, and psychological resilience.


Subject(s)
Bullying , Crime Victims , Resilience, Psychological , Child , Male , Humans , Cross-Sectional Studies , East Asian People , Bullying/psychology , Schools , Crime Victims/psychology
6.
Mikrochim Acta ; 186(7): 458, 2019 06 20.
Article in English | MEDLINE | ID: mdl-31222383

ABSTRACT

A sponge inspired three dimensional flexible aluminum foil based ZnO nanosheet array substrate is described for use in real-world surface enhanced Raman spectroscopic detection. Gold and silver nanoparticles were employed to form numerous hot spots on uniformly grown ZnO nanosheets on the substrate. This flexible spongy substrate can extract analytes (such as the fungicide thiram) from various complex sample surfaces by physical swabbing. Specifically, this substrate was applied to detect thiram on the surface of fruits and vegetables. Non-destructive recycling detection with a relative standard deviation of 6.1% was accomplished by monitoring the characteristic Raman peak at 1382 cm-1. This modified substrate has a low detection limit (0.2 ng cm-2 of thiram for apple and tomato), outstanding uniformity (relative standard deviation = 8.9%) and thermal stability (relative standard deviation = 0.9%). Graphical abstract Schematic representation of using a aluminum foil modified with ZnO nanosheets as a flexible and recyclable substrate for SERS analysis of pollutants. The substrate can be cleaned after use by UV irradiation.

7.
Chinese Journal of School Health ; (12): 1842-1845, 2019.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-815632

ABSTRACT

Objective@#To explore the relationship between psychological resilience and cognitive bias towards school violence in grade 3-5 primary school students in Luzhou city, so as to provide scientific basis for prevention and control of school violence in primary school students.@*Methods@#Students from grade 3-5 in primary schools in Luzhou were selected through stratified cluster random sampling method and were investigated with questionnaire survey.@*Results@#A total of 5 976 valid questionnaires were included, with an average score of psychological resilience (40.08±8.05) and an average score of school violence cognition (62.55±6.38). Multivariate results showed that psychological resilience was an independently associated with school violence perception (OR=1.04, P<0.01). The awareness of campus violence increased with resilience score. In addition, public school (OR=0.45) was associated with low awareness of school violence; senior grades (OR=1.77), girls (OR=1.20), and a greater number of friends(OR=1.37), student cadre(OR=1.37), middle/upper score in class(OR=2.13), no game playing(OR=1.33), no off-campus wandering(OR=1.78), timely parenting (OR=1.45) was associated with high awareness of school violence(P<0.05).@*Conclusion@#Psychological resilience positively correlates with cognition bias towards school violence. The higher the psychological resilience, the more positive perception of campus violence. Family, school and community-based interventions to enhance the resilience of students, increasing awareness towards school violence and ultimately reducing potential adverse impacts of school violence.

8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(2): 158-60, 164, 2013 Apr.
Article in Chinese | MEDLINE | ID: mdl-23662557

ABSTRACT

OBJECTIVE: To analyze the effect on pronunciation and comfort level when 4 different major connectors (type 1: Palatal plate; type 2: Single palatal strap; type 3: Anterior-posterior joint palatal strap; type 4: Anterior-posterior joint palatal bar) were used in patients with Kennedy I deletion. METHODS: Tirty young volunteers were chosen to wear 4 different major connectors. The pronunciation of consonants /s/, /t/, /j/, /sh/ were detected and the different formant parameters(F1 and F2) were analyzed by the computer speech analytical system. The comfort levels of 4 major connectors were compared by questionnaire survey. RESULTS: 1)There was no significant difference(P5).05) in pronunciation of consonants /s/, /sh/, /t/(F1 and F2) among the 4 types of connectors whatever wearing or not, but there was significant difference (P < 0.05) in pronunciation of consonant /j/ among wearing type 3, type 4 and no wearing. 2)There was no significant difference in comfort level (P > 0.05) among the four connectors. CONCLUSION: The effect on pronunciation of patients with Kennedy I deletion was less when wearing the first and the second types of connectors than that of wearing the third and the fourth types of connectors. There was no significant difference in comfort level among the four connectors.


Subject(s)
Denture Design , Denture, Partial, Removable , Aged , Dentition , Humans , Molar , Tooth, Deciduous
SELECTION OF CITATIONS
SEARCH DETAIL