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1.
Heliyon ; 10(18): e37679, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39309796

ABSTRACT

Background: The incidence of mobile phone addiction (MPA) is increasing in undergraduates and may lead to depression, anxiety, and sleep disorders. Undergraduate nursing students are important group for clinical services; therefore poor mental health has an important implications for the quality of future nursing work and the relationship between nurses and patients. Objectives: To explore the connection between organizational caring and MPA in Chinese undergraduate nursing students and to investigate the mechanisms of perceived stress and self-control in this relationship by constructing a chain mediation model. Design: A cross-sectional study. Methods: A total of 900 participants (age range 18-25 years, M = 20.99, SD = 1.58, 94.0 % female) were recruited from 10 universities in China. Data were collected using an online survey between February and March 2023. Organizational caring, subjective stress, self-control ability, and MPA among undergraduate nursing students were assessed. Results: (1) The prevalence of MPA was 34.9 % (314/900). (2) MPA in undergraduate nursing students was negatively correlated with self-control (r = -0.468, p < 0.001) and organizational caring (r = -0.156, p < 0.001), and positively correlated with perceived stress (r = 0.362, p < 0.001). (3) Perceived stress and self-control mediated the relationship between organizational caring and MPA, and the relative mediating effect values were 16.6 % and 17.2 %, respectively. (4) Organizational caring had an indirect effect on MPA through the chain mediation effect of perceived stress and self-control, and the relative mediating effect value was 19.1 %. Conclusion: Organizational caring, perceived stress and self-control directly influenced MPA among undergraduate nursing students. Additionally, organizational caring indirectly affected MPA through perceived stress and self-control. To further mitigate MPA among students, nursing managers and educators should enhance organizational caring, reduce perceived stress, and improve self-control abilities.

2.
J Educ Health Promot ; 13: 233, 2024.
Article in English | MEDLINE | ID: mdl-39297097

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) can be complicated by malnutrition, which has adverse implications on patients' health outcomes and quality of life. CKD patients from different sociocultural contexts may have varying perceptions of knowledge, attitudes, and practices of malnutrition. However, information on the perception of malnutrition in patients with CKD is limited. This study aimed to explore and describe the knowledge, attitude, and practice of patients with CKD disease regarding malnutrition. MATERIALS AND METHODS: A qualitative-descriptive design was used. Thirteen participants were selected through a purposive sampling technique among malnourished CKD patients from a hospital in Xi'an Provincial Hospital of Traditional Chinese Medicine between November 2022 and January 2023. Data were collected through face-to-face semistructured interviews until data saturation. All participants were informed about the study. Data obtained were analyzed by content analysis. RESULTS: Three main categories and seven subcategories were extracted from the data analysis: 1) knowledge (basic knowledge acquisition and understanding, knowledge misconceptions, and confusion, nutrition knowledge, and culture collision); 2) attitude (negative attitudes and adverse situations, positive attitude and self-awareness); 3) practice (disadvantageous and passive practice, favorable practice). CONCLUSION: This study provided insight into the knowledge, attitude, and practice of malnutrition in patients with CKD. Our findings can serve as important baseline data for the development of future interventions that can help reduce the risk of malnutrition, slow disease progression, and improve the quality of life in patients with CKD.

3.
Philos Trans A Math Phys Eng Sci ; 382(2281): 20230319, 2024 Oct 23.
Article in English | MEDLINE | ID: mdl-39246088

ABSTRACT

On 13-15 January 2022, the Hunga Tonga-Hunga Ha'apai underwater volcano erupted. This powerful eruption generated infrasonic waves with amplitudes of thousands of Pascals in the near field. The ground infrasonic stations in China, located approximately 10 000 km from the Hunga volcano, also received waves with frequencies from 0.01 to 0.05 Hz. However, the amplitude reached 17 Pa, which is higher than the predicted amplitude using the absorption model without considering the dispersion effect in the thin thermosphere. At high altitudes, dispersion exists and the sound speed depends on the ratio of the molecular mean collision ratio to sound frequency, which is proportional to the ratio (frequency/pressure). And attenuation coefficients are complex to model. We simulate dispersive sound speeds and attenuation coefficients at different frequencies according to theory and our experimental data. In the thermosphere, the dispersion effect causes noticeable changes of sound speed and then affects wave propagation paths in the far field. The abnormal attenuation coefficient has a smaller impact on thermospheric returns than that of the dispersive sound speed, but it is also not negligible. It explains the large amplitude of thermospheric signals received in our infrasound stations. This article is part of the theme issue 'Celebrating the 15th anniversary of the Royal Society Newton International Fellowship'.

4.
Org Lett ; 26(34): 7233-7238, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39158221

ABSTRACT

A new trifluoroacetylation reagent was developed by using inexpensive and readily available trifluoroacetic anhydride and N-phenyl-4-methylbenzenesulfonamide for the first time. The reaction of (het)aryl boronic acids with the new trifluoroacetylation reagent, N-phenyl-N-tosyltrifluoroacetamide, proceeded smoothly in the presence of a palladium catalyst to provide trifluoromethyl ketones in satisfactory to excellent yields. Various groups, including the synthetically useful functional groups Cl, TMS, and PhCO, were tolerated well under the current reaction conditions. This new trifluoroacetylation reagent can be used in the large-scale synthesis of trifluoromethyl ketones, even at a low palladium catalyst loading.

5.
Org Lett ; 26(28): 6024-6029, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-38984734

ABSTRACT

A new radical difluoromethylation was developed by using inexpensive and readily available difluoroacetic anhydride and N-phenyl-4-methylbenzenesulfonamide for the first time. The reaction of arylboronic acids with the new difluoromethylation reagent, N-phenyl-N-tosyldifluoroacetamide, proceeded smoothly in the presence of palladium catalyst to provide difluoromethylarenes in satisfactory to excellent yields. The electronic property (electron-donating or electron-withdrawing) of the substituent linked to the aromatic ring did not considerably influence the reactivity of arylboronic acid. Various groups, including the synthetically useful functional groups Cl, CN, and NO2, were tolerated well under the current reaction conditions.

6.
Ecotoxicol Environ Saf ; 283: 116811, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39083873

ABSTRACT

In this work, the relationship and kinetics of biodegradation and bio-adsorption of benzo[a]pyrene (BaP) by Bacillus and Ascomycota were explored, and the metabolites of BaP under mixed microbial coculture were analyzed and characterized. The results show that BaP was removed through both biosorption and biodegradation. Under mixed microbial coculture, biosorption played a significant role in the early stage and biodegradation was predominant in the later stage. During the removal of BaP, the fungi exhibited remarkable adsorption capabilities for BaP with an adsorption efficiency (AE) of 38.14 %, while bacteria had a best degradation for BaP with a degradation efficiency (DE) of 56.13 %. Under the mixed microbial culture, the removal efficiency (RE) of BaP by the synergistic action of fungi and bacteria reached up to 76.12 % within 15 days. Kinetics analysis illustrated that the degradation and adsorption process of BaP were well fit to the first-order and the pseudo-second-order kinetic models, respectively. The research on the relationship between degradation and adsorption during microbial removal of BaP, as well as the synergistic effects of fungi and bacteria, will provide a theoretical guidance for two or even synthetic microbial communities.


Subject(s)
Benzo(a)pyrene , Biodegradation, Environmental , Coculture Techniques , Benzo(a)pyrene/metabolism , Adsorption , Kinetics , Bacillus/metabolism , Ascomycota/metabolism , Fungi/metabolism , Bacteria/metabolism
7.
BMC Nurs ; 23(1): 404, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886795

ABSTRACT

BACKGROUND: As indispensable reserves for the nursing workforce, undergraduate nursing students must possess self-directed learning abilities to consistently update their professional knowledge and adapt to the evolving demands of professional development. The acquisition of self-directed learning abilities can help undergraduate nursing students augment their theoretical knowledge and refine their clinical practice skills, thus fulfilling the demand from patients for high-quality nursing services. Hence, comprehending and investigating the factors that influence the development of self-directed learning abilities in nursing students is of paramount importance for nursing education and advancement of the nursing profession. OBJECTIVES: This study investigated the status of and associations between perceived stress, psychological capital, and self-directed learning abilities among undergraduate nursing students. Additionally, it examines the mediating role of psychological capital in the relationship between perceived stress and self-directed learning abilities. Thus, aiming to provide nursing educators with new directions for enhancing self-directed learning abilities. DESIGN: A cross-sectional descriptive study. METHODS: In February and March 2023, 900 undergraduate nursing students from 10 nursing schools completed an online questionnaire. The questionnaire included measures of perceived stress, psychological capital, and self-directed learning ability. Data were analyzed using SPSS 27.0 and the PROCESS macro tool. RESULTS: The scores for perceived stress, psychological capital, and self-directed learning ability among undergraduate nursing students were 40.07 ± 5.90, 99.89 ± 16.59, and 87.12 ± 9.20, respectively. Self-directed learning abilities were negatively correlated with perceived stress (r = -0.415, p < 0.001) and positively correlated with psychological capital (r = 0.465, p < 0.001). Perceived stress was negatively correlated with psychological capital (r = -0.630, p < 0.001). Psychological capital partially mediated the relationship between perceived stress and self-directed learning abilities among undergraduate nursing students, with a mediation effect of -0.166, accounting for 49.55% of the total effect. CONCLUSION: This study found that undergraduate nursing students perceived high levels of stress, possessed low levels of psychological capital, and had moderate levels of self-directed learning. Perceived stress and psychological capital directly influenced undergraduate nursing students' self-directed learning abilities, and perceived stress indirectly affected self-directed learning abilities through psychological capital. Nursing managers and educators should alleviate the perceived stress of undergraduate nursing students and cultivate their positive psychological capital to enhance self-directed learning abilities.

8.
Org Biomol Chem ; 22(6): 1141-1145, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38214226

ABSTRACT

A strategy for direct synthesis of phenanthrenyl triflates from 1-biphenylyl-2-diazo-2-aryl ketones and triflic anhydride is described. The reaction of 1-biphenylyl-2-diazo-2-aryl ketones with triflic anhydride proceeded smoothly in the presence of 2,6-di-tert-butylpyridine under mild conditions to produce phenanthrenyl triflates in high to excellent yields. The phenanthrenyl triflate products were demonstrated to be utilized as coupling partners in various coupling reactions. The proposed mechanism involves an intramolecular Friedel-Crafts reaction of a vinyl cation intermediate formed in situ.

9.
Nat Commun ; 14(1): 7669, 2023 Nov 23.
Article in English | MEDLINE | ID: mdl-37996494

ABSTRACT

Carbon-introducing difunctionalization of C-C double bonds enabled by transition-metal catalysis is one of most straightforward and efficient strategies to construct C-C and C-X bonds concurrently from readily available feedstocks towards structurally diverse molecules in one step; however, analogous difunctionalization for introducing germanium group and other functionalities remains elusive. Herein, we describe a nickel-catalyzed germylative alkylation of activated olefins with easily accessible primary, secondary and tertiary alkyl bromides and chlorogermanes as the electrophiles to form C-Ge and C-Calkyl bonds simultaneously. This method provides a modular and facile approach for the synthesis of a broad range of alkylgermanes with good functional group compatibility, and can be further applied to the late-stage modification of natural products and pharmaceuticals, as well as ligation of drug fragments. More importantly, this platform enables the expedient synthesis of germanium substituted ospemifene-Ge-OH, which shows improved properties compared to ospemifene in the treatment of breast cancer cells, demonstrating high potential of our protocol in drug development.

10.
Org Biomol Chem ; 21(29): 6034-6038, 2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37439118

ABSTRACT

A strategy for the synthesis of multisubstituted propenylbenzenes using benzyl chlorides as starting materials is described. The palladium-catalyzed allylative dearomatization and the subsequent Wagner-Meerwein rearrangement as well as the olefin isomerization proceeded smoothly under mild conditions to produce propenylation products in good yields with high regioselectivity. Control experiments and cyclic voltammetry analysis suggest that Bu3SnCl, a by-product generated in the first step of allylative dearomatization, plays an essential role in the third step of olefin isomerization in the presence of a Brønsted acid.

11.
J Environ Manage ; 336: 117615, 2023 Jun 15.
Article in English | MEDLINE | ID: mdl-36893541

ABSTRACT

The bioleaching process is widely used in the treatment of ores or solid wastes, but little is known about its application in the treatment of vanadium-bearing smelting ash. This study investigated bioleaching of smelting ash with Acidithiobacillus ferrooxidans. The vanadium-bearing smelting ash was first treated with 0.1 M acetate buffer and then leached in the culture of Acidithiobacillus ferrooxidans. Comparison between one-step and two-step leaching process indicated that microbial metabolites could contribute to the bioleaching. The Acidithiobacillus ferrooxidans demonstrated a high vanadium leaching potential, solubilizing 41.9% of vanadium from the smelting ash. The optimal leaching condition was determined, which was 1% pulp density, 10% inoculum volume, an initial pH of 1.8, and 3 Fe2+g/L. The compositional analysis showed that the fraction of reducible, oxidizable, and acid-soluble was transferred into the leaching liquor. Therefore, as the alternative to the chemical/physical process, an efficient bioleaching process was proposed to enhance the recovery of vanadium from the vanadium-bearing smelting ash.


Subject(s)
Acidithiobacillus , Vanadium , Acidithiobacillus/metabolism
12.
RSC Adv ; 13(5): 3371-3376, 2023 Jan 18.
Article in English | MEDLINE | ID: mdl-36756435

ABSTRACT

An efficient and highly selective heterogeneous catalyst system for hydroamination of alkynes was developed using unsupported gold nanopores (AuNPore) for the first time. The AuNPore-catalyzed highly regioselective hydroamination of alkynes proceeded smoothly without any additive and solvent under mild conditions (rt-50 °C) to yield Markovnikov imines in satisfactory to excellent yields. No gold leached from AuNPore during the hydroamination of alkynes. Moreover, the catalyst was easily recovered and reused without any loss of catalytic activity. A one-pot, two-step procedure using a single AuNPore catalyst has been devised to produce secondary amines derived from readily available alkynes and anilines with high atom efficiency.

13.
J Hazard Mater ; 443(Pt A): 130164, 2023 Feb 05.
Article in English | MEDLINE | ID: mdl-36308938

ABSTRACT

This study proposed the fluidization-like dielectric barrier discharge (DBD) plasma for the remediation of lindane contaminated soil and integrated physical and chemical reaction pathway. Soil particle distribution within the reactor was simulated with Euler-Euler and Gidaspow drag models, and a bipolar pulsed power supply was applied to energize the DBD reactor after full fluidized. The effect of soil particles movement on electric features was discussed in terms of voltage waveforms and Lissajous figures. Lindane degradation was found to be related to electrics parameters and soil properties. Soil samples before and after treatment were analyzed by XRD and SEM methods. A 95.98% lindane decomposition and 0.66 mgLindane/h average reaction rate were obtained with 3 wt% CaO injection by pulse power drove fluidization-like DBD after 32 min treatment. Ozone was proved to play a major role during lindane degrading by plasma. The reaction potential pathway of lindane decomposition contains 4 steps, including dehydrogen, dehydrochlorination, and dechlorination, respectively.


Subject(s)
Environmental Restoration and Remediation , Soil Pollutants , Hexachlorocyclohexane/chemistry , Soil Pollutants/chemistry , Soil , Environmental Pollution
14.
Water Sci Technol ; 86(8): 1958-1968, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36315088

ABSTRACT

Ciprofloxacin (CIP) is a kind of widely used fluoroquinolone antibiotic, and the widespread presence of CIP in aquatic environment has become a serious issue. Mechanochemical treatment (MCT), as an effective approach to degrade persistent organic pollutants, has many advantages of low cost, simplicity, and being environmentally innocuous. However, little attention has been paid to employing MCT to treat effluents containing CIP. In this study, MCT was introduced to degrade CIP in aquatic solutions. A series of CIP degradation experiments were conducted by a planetary ball mill, and the influences of main parameters on CIP degradation efficiency were investigated. Furthermore, an optimum combination was selected through orthogonal experiments, and CIP degradation efficiency could reach as high as 99% in certain conditions. Besides, the biotoxicity of CIP solution was also studied. MCT exhibits satisfying performance for degrading CIP in solutions, which makes MCT a promising approach to CIP elimination and also encourages further applications in treating effluents containing other organic pollutants.


Subject(s)
Environmental Pollutants , Water Pollutants, Chemical , Ciprofloxacin/analysis , Anti-Bacterial Agents/metabolism , Fluoroquinolones
15.
Phytochemistry ; 203: 113377, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35988742

ABSTRACT

Cichorium intybus L. (Asteraceae), belonging to the tribe Cichorieae of the family Asteraceae, has a long history as an edible and medicinal food. Sesquiterpene lactones are commonly considered as its major active constituents. In the current study, five unreported sesquiterpene lactones, including one 12,8-guaianolide and four 12,6-guaianolides were isolated from C. intybus roots, as well as 16 known analogues. The planar structures and relative configurations of these compounds were elucidated by extensive spectroscopic analysis. The absolute configurations were determined by the time-dependent density functional theory (TDDFT)-based electronic circular dichroism (ECD) calculation method. Bioassay results showed that seven of the isolates exhibited remarkable NO production inhibitory activity in LPS-stimulated RAW264.7 macrophages, with IC50 values ranging from 1.83 to 38.81 µM. Some of them can significantly decrease the secretion of inflammatory cytokines (TNF-α and IL-6). Cytotoxicity assays demonstrated that intybusins B, as well as four known compounds, displayed obvious inhibitory activities against four human tumor cells, with IC50 values ranging from 9.01 to 27.07 µM.


Subject(s)
Antineoplastic Agents , Asteraceae , Cichorium intybus , Sesquiterpenes , Anti-Inflammatory Agents/pharmacology , Asteraceae/chemistry , Humans , Interleukin-6 , Lactones/chemistry , Lactones/pharmacology , Lipopolysaccharides/pharmacology , Molecular Structure , Phytochemicals/pharmacology , Sesquiterpenes/chemistry , Sesquiterpenes/pharmacology , Tumor Necrosis Factor-alpha
16.
Water Sci Technol ; 86(3): 555-567, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35960836

ABSTRACT

Sulfidated nano zero-valent iron supported by activated carbon (S-nZVI/AC) composites were synthesized via liquid phase reduction method, and then they were used for Cr(VI) elimination. Characterization results showed that Fe0 was the main component, besides, iron oxides and iron sulfides were also detected. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results showed that S-nZVI nanoparticles were homogeneously distributed on the surfaces of AC. The influences of S/Fe ratio, C/Fe ratio, pH value, reaction temperature and co-existed ions (Cl-, SO42-, PO43- and NO3-) on Cr(VI) removal performances were investigated. Furthermore, the corresponding mechanisms were also discussed. The S-nZVI/AC composites exhibited good aging-resistance performances that Cr(VI) removal efficiency still maintained at 83.1% after being sealed in water for seven days, and they also had satisfying cycling stabilities that Cr(VI) removal efficiency only decreased less than 10% after four cycles. The good performances of S-nZVI/AC composites for Cr(VI) removal are attributed to the protection effect of iron sulfides and immobilization effect of AC, making S-nZVI/AC as a promising candidate for Cr(VI) elimination in effluents.


Subject(s)
Water Pollutants, Chemical , Adsorption , Chromium/chemistry , Iron/chemistry , Sulfides , Water Pollutants, Chemical/chemistry
17.
J Org Chem ; 87(15): 10531-10538, 2022 Aug 05.
Article in English | MEDLINE | ID: mdl-35899766

ABSTRACT

Palladium-catalyzed para-C-H bond amination of 2-aryl chloromethylbenzenes is described for the first time. The reactions of 2-aryl chloromethylbenzenes with cyclic amines proceeded smoothly in the presence of Pd(acac)2, tri(2-furyl)phosphine, and NaH in tetrahydrofuran at 40 °C to provide para-C-H bond aminated products in satisfactory to high yields with acceptable regioselectivity in most cases. The electronic property of the substituents linked to the benzene rings did not significantly influence the reactivity of the 2-aryl chloromethylbenzene substrates and the reaction regioselectivity.

18.
Nanoscale ; 14(26): 9341-9348, 2022 Jul 07.
Article in English | MEDLINE | ID: mdl-35704927

ABSTRACT

An efficient and highly selective heterogeneous catalyst system for nitrile hydrogenation was developed using unsupported palladium nanopores (PdNPore). The PdNPore-catalyzed selective hydrogenation of nitriles proceeded smoothly, without any additives, under mild conditions (low H2 pressure and low temperature) to yield primary amines with satisfactory to excellent yields. Systematic studies demonstrated that the high activity and excellent selectivity of the PdNPore originated from its good Lewis acidity and porous structure. No palladium leached from the PdNPore during the hydrogenation reaction. Moreover, the catalyst was easily recovered and reused without any loss of catalytic activity. A deuterium-hydrogen exchange reaction clearly indicated that the present hydrogenation involves heterolytic H2 splitting on the surface of the PdNPore catalyst.

19.
J Org Chem ; 87(12): 8229-8236, 2022 06 17.
Article in English | MEDLINE | ID: mdl-35658456

ABSTRACT

A strategy for the synthesis of spirocarbocycles by using chloromethyl arenes as starting materials is described in this paper. The palladium-catalyzed allylative dearomatization and the subsequent ruthenium-catalyzed ring closure metathesis proceeded smoothly under mild conditions to produce the corresponding spirocarbocycle products with moderate to high yields. Benzene-ring-, naphthalene-ring-, and anthracene-ring-containing substrates can be easily transformed into spirocarbocycles by using the proposed method.


Subject(s)
Palladium , Ruthenium , Catalysis , Cyclization
20.
Org Lett ; 24(14): 2596-2600, 2022 Apr 15.
Article in English | MEDLINE | ID: mdl-35389668

ABSTRACT

A palladium-catalyzed cycloisomerization of 2-ethynylbiaryls to 9-methylidene fluorenes is described for the first time. The cycloisomerization of 2-ethynylbiaryls proceeded smoothly in the presence of weak acid at low temperature to afford 9-methylidene fluorenes in satisfactory to high yields. This new type of cycloisomerization of 2-ethynylbiaryls is operationally simple and scalable and exhibits high functional-group tolerance. Various synthetically useful functional groups, such as halogen atoms, as well as formyl, acetyl, methoxycarbonyl, cyano, and nitro groups, remain intact during the cycloisomerization of 2-ethynylbiaryls.

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