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1.
Nano Lett ; 24(6): 1851-1858, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38315876

RESUMEN

Interlayer excitons, with prolonged lifetimes and tunability, hold potential for advanced optoelectronics. Previous research on the interlayer excitons has been dominated by two-dimensional heterostructures. Here, we construct WSe2/GaN composite heterostructures, in which the doping concentration of GaN and the twist angle of bilayer WSe2 are employed as two ingredients for the manipulation of exciton behaviors and polarizations. The exciton energies in monolayer WSe2/GaN can be regulated continuously by the doping levels of the GaN substrate, and a remarkable increase in the valley polarizations is achieved. Especially in a heterostructure with 4°-twisted bilayer WSe2, a maximum polarization of 38.9% with a long lifetime is achieved for the interlayer exciton. Theoretical calculations reveal that the large polarization and long lifetime are attributed to the high exciton binding energy and large spin flipping energy during depolarization in bilayer WSe2/GaN. This work introduces a distinctive member of the interlayer exciton with a high degree of polarization and a long lifetime.

2.
Nano Lett ; 24(4): 1415-1422, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38232178

RESUMEN

Charge and spin are two intrinsic attributes of carriers governing almost all of the physical processes and operation principles in materials. Here, we demonstrate the manipulation of electronic and spin states in designed Co-quantum dot/WS2 (Co-QDs/WS2) heterostructures by employing a metal-dielectric composite substrate and via scanning tunneling microscope. By repeatedly scanning under a unipolar bias, switching the bias polarity, or applying a pulse through nonmagnetic or magnetic tips, the Co-QDs morphologies exhibit a regular and reproducible transformation between bright and dark dots. First-principles calculations reveal that these tunable characters are attributed to the variation of density of states and the transition of magnetic anisotropy energy induced by carrier accumulation. It also suggests that the metal-dielectric composite substrate is successful in creating the interfacial potential for carrier accumulation and realizes the electrically controllable modulations. These results will promote the exploration of electron-matter interactions in quantum systems and provide an innovative way to facilitate the development of spintronics.

3.
J Biol Chem ; 298(8): 102160, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35724961

RESUMEN

C-reactive protein (CRP) is a major acute phase protein and inflammatory marker, the expression of which is largely liver specific and highly inducible. Enhancers are regulatory elements critical for the precise activation of gene expression, yet the contributions of enhancers to the expression pattern of CRP have not been well defined. Here, we identify a constitutively active enhancer (E1) located 37.7 kb upstream of the promoter of human CRP in hepatocytes. By using chromatin immunoprecipitation, luciferase reporter assay, in situ genetic manipulation, CRISPRi, and CRISPRa, we show that E1 is enriched in binding sites for transcription factors STAT3 and C/EBP-ß and is essential for the full induction of human CRP during the acute phase. Moreover, we demonstrate that E1 orchestrates with the promoter of CRP to determine its varied expression across tissues and species through surveying activities of E1-promoter hybrids and the associated epigenetic modifications. These results thus suggest an intriguing mode of molecular evolution wherein expression-changing mutations in distal regulatory elements initiate subsequent functional selection involving coupling among distal/proximal regulatory mutations and activity-changing coding mutations.


Asunto(s)
Proteína C-Reactiva , Elementos de Facilitación Genéticos , Sitios de Unión , Proteína C-Reactiva/genética , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Regulación de la Expresión Génica , Hepatocitos , Humanos , Regiones Promotoras Genéticas , Factor de Transcripción STAT3/metabolismo , Transcripción Genética
4.
J Obstet Gynaecol Res ; 49(6): 1481-1490, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37002620

RESUMEN

AIM: To investigate the status quo of cognitive appraisal of health and its influencing factors among pregnant women with gestational diabetes mellitus. METHODS: A cross-sectional survey was conducted from June 2020 to November 2020. Participants were recruited from a tertiary hospital by a convenient sample method. A total of 300 pregnant women with gestational diabetes mellitus completed the survey, including self-compiled individual information questionnaire, Cognitive Appraisal of Health Scale, Pregnancy Stress Rating Scale and General Self-Efficacy Scale. RESULTS: For cognitive appraisal of health, the median score of challenge dimension was 3.75 (3.50, 4.00), benign/irrelevant was 2.75 (2.00, 3.50), harm/loss was 2.38 (2.00, 3.00) and threat was 2.40 (2.00, 2.80), respectively. Regression analyses showed that gestational age, mode of conception, history of abortion, insulin usage, pregnancy stress and self-efficacy were the predictors of cognitive appraisal of health. CONCLUSIONS: This study revealed that pregnant women with gestational diabetes mellitus tended to make positive cognitive appraisal of health. And healthcare providers need to make full use of their predictors of cognitive appraisal of health to improve cognitive appraisal to manage stress and ameliorate pregnancy outcomes.


Asunto(s)
Aborto Espontáneo , Diabetes Gestacional , Embarazo , Femenino , Humanos , Estudios Transversales , Mujeres Embarazadas , Cognición
5.
J Clin Nurs ; 32(7-8): 1025-1044, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35460127

RESUMEN

AIMS AND OBJECTIVES: To systematically evaluate the effects of decision aids for women facing breast reconstruction decision on decision conflict, decision regret, knowledge, satisfaction, anxiety and depression. BACKGROUND: Breast reconstruction decision is not good or bad and should be guided by clinical evidence and patient preferences. Decision aids can increase the patient's decision-making enthusiasm and ability, improve the quality of decision and promote shared decision-making between patients and medical staff. DESIGN: Systematic review and meta-analysis. METHODS: Eight databases were conducted from the establishment of the database until October 2021. The PRISMA checklist was selected for analysis in this paper. The meta-analysis was conducted in Review Manager 5.3. The quality of the studies was assessed using the Cochrane risk-of-bias tool. The result is decision conflict, decision regret, knowledge and other secondary outcomes. Sensitivity analysis and subgroup analysis were also conducted. RESULTS: A total of twelve randomised controlled trials (RCTs) were included in the systematic review and meta-analysis. Meta-analysis revealed that decision aids could significantly reduce decision conflict and decision regret, improve knowledge, satisfaction and depression and had no influence on anxiety. CONCLUSIONS: The results of the systematic review and meta-analysis reviewed the positive effect of decision aids on the decision-making of women facing postmastectomy breast reconstruction. In the future, more well-designed RCTs are needed to confirm the effects of decision aids on the decision-making of breast reconstruction and nurses should be encouraged to take part in the development of decision aids in accordance with strict standards and apply them to breast cancer patients considering postmastectomy breast reconstruction. RELEVANCE TO CLINICAL PRACTICE: Our study provides evidence for the effectiveness of decision aids on breast reconstruction and points to the important role of healthcare providers in the use of decision aids and in facilitating shared decision-making.


Asunto(s)
Ansiedad , Mamoplastia , Femenino , Humanos , Emociones , Trastornos de Ansiedad , Técnicas de Apoyo para la Decisión , Ensayos Clínicos Controlados Aleatorios como Asunto
6.
J Adv Nurs ; 77(10): 3964-3979, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33942356

RESUMEN

AIMS: To analyse the effect of decision aids (DAs) used by pregnant women on prenatal testing decisions. DESIGN: Systematic review and meta-analysis. DATA RESOURCES: We searched Embase, PubMed, Web of Science and the Cochrane Central Library ending October 2020. REVIEW METHODS: Papers were selected for analysis in accordance with the PRISMA guidelines. The meta-analysis was carried out using Review Manager 5.3 software. The quality of the studies was assessed using the risk of bias tool recommended by the Cochrane Handbook. The result is knowledge, decision conflict, anxiety and other secondary outcomes. RESULTS: A total of 18 studies were included in the systematic review and meta-analysis. Comprehensive analysis showed that DAs could significantly improve knowledge and decision-making satisfaction, reduce decision conflict, increase the proportion of women who make informed choice and had no influence on anxiety and decision regret. CONCLUSIONS: This article systematically reviewed the positive effect of DAs on the decision-making of pregnant women facing prenatal testing. In the future, nurses should be encouraged to develop DAs in accordance with strict standards and apply them to pregnant women of different backgrounds. IMPACT: There is a growing consensus that health care should be patient-centred, and the values and preferences of pregnant women who undergo prenatal testing need to be incorporated into the clinical decision-making process. This review reports that the use of DAs can increase pregnant women's chances of participating in prenatal testing decisions and may improve the quality of their decision-making. It also provides information on the role and practice of nurses in promoting evidence-based prenatal testing for DAs.


Asunto(s)
Técnicas de Apoyo para la Decisión , Participación del Paciente , Trastornos de Ansiedad , Toma de Decisiones Clínicas , Femenino , Humanos , Embarazo
7.
J Clin Nurs ; 2021 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-34738288

RESUMEN

AIMS AND OBJECTIVES: Review the content, quality and effect of breast cancer screening decision aids (BCS-DAs) in women approximately 50 years of age to provide a basis for the development of DAs. BACKGROUND: Breast cancer screening (BCS) decisions are complex and should vary depending on a woman's risk of breast cancer and her values and preferences. Decision aids (DAs) can help support women and medical staff in shared decision-making (SDM) when solving BCS problems. DESIGN: Systematic review and meta-analysis. METHODS: Four databases were searched starting at the time of establishment of the database to March 2021. The PRISMA checklist was followed. The meta-analysis was carried out using Review Manager 5.3 software. The quality of the studies was assessed using the risk of bias tool recommended by the Cochrane Handbook. The quality of the DAs was assessed using the International Standards for Decision Aid (IPDASi v4.0). RESULTS: The search strategy obtained 2024 references. After abstraction and full text screening, a total of seven studies were included. This article systematically reviews the content, quality and effectiveness of DAs in seven RCTs in helping women to make BCS decisions. The DAs were mostly in paper or online form and displayed disease screening information, analysed the benefits and harms of options and clarified the value to patients. Among all the DAs, only one met the minimum quality standards of IPDASi v4.0. Comprehensive analysis shows that DAs can significantly improve knowledge and increase the proportion of women who make informed choices, but they have no effect on screening attitude, intention, decision conflict or regret. CONCLUSIONS: In the future, nurses should be encouraged to develop DAs in accordance with strict standards and to make them applicable to young women of different backgrounds. RELEVANCE TO CLINICAL PRACTICE: The result may be provide a basis for the development of DAs to promote women's informed screening choices.

8.
Nano Lett ; 18(3): 1724-1732, 2018 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-29433320

RESUMEN

We report an experimental observation and direct control of quantum transport in artificial two-dimensional Au lattices. Combining the advanced techniques of low-temperature deposition and newly developed double-probe scanning tunneling spectroscopy, we display a two-dimensional carrier transport and demonstrate a strong in-plane transport modulation in the two-dimensional Au lattices. In well-ordered Au lattices, we observe the carrier transport behavior manifesting as a band-like feature with an energy gap. Furthermore, controlled structural modification performed by constructing coupled "stadiums" enables a transition of system dynamics in the lattices, which in turn establishes tunable resonant transport throughout a wide energy range. Our findings open the possibility of the construction and transport engineering of artificial lattices by the geometrical arrangement of scatterers and quantum chaotic dynamics.

9.
Nano Lett ; 17(3): 1642-1647, 2017 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-28140593

RESUMEN

Combined scanning tunneling microscopy, spectroscopy, and local barrier height (LBH) studies show that low-temperature-cleaved optimally doped Ba(Fe1-xCox)2As2 crystals with x = 0.06, with Tc = 22 K, have complicated morphologies. Although the cleavage surface and hence the morphologies are variable, the superconducting gap maps show the same gap widths and nanometer size inhomogeneities irrelevant to the morphology. Based on the spectroscopy and LBH maps, the bright patches and dark stripes in the morphologies are identified as Ba- and As-dominated surface terminations, respectively. Magnetic impurities, possibly due to Co or Fe atoms, are believed to create local in-gap state and, in addition, suppress the superconducting coherence peaks. This study will clarify the confusion on the cleavage surface terminations of the Fe-based superconductors and its relation with the electronic structures.

10.
Tumour Biol ; 37(3): 3697-704, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26462839

RESUMEN

Radiofrequency ablation (RFA) represents a valuable choice in hepatocellular carcinoma (HCC); however, local recurrence of HCC is common after RFA. Here, 20 primary HCC patients treated by RFA were enrolled. Before (termed 0d) and after RFA treatment for 1 and 7 days (termed 1d and 7d, respectively), plasma and noncancerous tissue were collected. ELISA assay showed that plasma C-X-C motif chemokine 10 (CXCL10) was increased in ten patients (type I patients) but decreased in the other 10 patients (type II patients). The mean interval for HCC recurrence in type I patients was less than the mean interval in type II patients. Interestingly, a significant negative correlation between interval for HCC recurrence and fold change of plasma CXCL10 (1d/0d or 7d/0d) was identified, suggesting that RFA-induced CXCL10 is associated with earlier HCC recurrence. Immunofluorescence assay showed that the receptor of CXCL10, chemokine (C-X-C motif) receptor 3 (CXCR3), was significantly increased in type I, but not type II, patients after RFA. In vitro assay demonstrated that CXCL10 stimulus increased the rate of CD133(+) cancer stem cells (CSCs) in HepG2 cells by binding to CXCR3 and then inducing c-Myc expression. Many studies have reported that induction of CD133(+) CSCs contributes to HCC recurrence. Thus, CXCL10-increased CD133(+) CSCs by activating CXCR3/c-Myc pathway might accelerate HCC recurrence after RFA. These data might have potential implications for HCC therapy.


Asunto(s)
Carcinoma Hepatocelular/cirugía , Ablación por Catéter/métodos , Quimiocina CXCL10/metabolismo , Neoplasias Hepáticas/cirugía , Células Madre Neoplásicas/metabolismo , Antígeno AC133/metabolismo , Adulto , Anciano , Carcinoma Hepatocelular/sangre , Carcinoma Hepatocelular/metabolismo , Quimiocina CXCL10/sangre , Quimiocina CXCL10/genética , Ensayo de Inmunoadsorción Enzimática , Células Hep G2 , Humanos , Immunoblotting , Neoplasias Hepáticas/sangre , Neoplasias Hepáticas/metabolismo , Masculino , Microscopía Fluorescente , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Receptores CXCR3/genética , Receptores CXCR3/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
11.
Ecotoxicol Environ Saf ; 117: 141-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25855213

RESUMEN

During the long and cold winter season in northern area of China, wastewater treatment is often inefficient which causes the substandard discharge. In this study, a lead-resistant psychrotrophilic bacterium was isolated and used as an adsorbent to remove Pb(II) from aqueous solution at 15 °C. The strain was identified and designated as Bacillus sp. PZ-1 based on the morphology, physiological-biochemical experiments and 16S rDNA sequence analysis. The minimal inhibitory concentration and antibiotic experiments revealed that PZ-1 had high resistance to 1500 mg L(-1) of Zn(II), 800 mg L(-1) of Cu(II), 400 mg L(-1) of Ni(II), 15 µg mL(-1) of chloramphenicol and 50 µg mL(-1) of streptomycin, but susceptibility to 200 mg L(-1) of Co(II). Scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic force microscopy analyses showed that biosorption of Bacillus sp. PZ-1 to Pb(II) involved surface adsorption, ion exchange and micro-precipitate. Fourier transform infrared spectroscopy analyses indicated that hydroxyl, carbonyl and carboxyl on cells may play vital roles in Pb(II) adsorption. Besides, siderophore secreted by PZ-1 had beneficial impacts on the Pb(II) removal. Biosorption experiments were carried out as a function of initial Pb(II) concentration (50-500 mg L(-1)), pH (3.0-7.0), biomass concentration (5-50 g L(-1)) and contact time (5-40 min). Biosorption rate of 93.01% with adsorption capacity of 9.30 mg g(-1) was obtained under the initial Pb(II) concentration of 400 mg (-1), pH of 5.0, contact time of 20 min, biomass concentration of 40 g L(-1) and the temperature of 15 °C. The equilibrium data were well fitted with Langmuir model, which indicated the adsorption process of Pb(II) is monolayer adsorption. Bacillus sp. PZ-1 appeared to be an efficient biosorbent for removing Pb(II) from wastewater at low temperature.


Asunto(s)
Bacillus/química , Plomo/aislamiento & purificación , Sideróforos/metabolismo , Adsorción , Bacillus/aislamiento & purificación , Bacillus/metabolismo , Biomasa , China , Concentración de Iones de Hidrógeno , Microscopía Electrónica de Rastreo , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Aguas Residuales
12.
J Colloid Interface Sci ; 666: 585-593, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38613980

RESUMEN

Capacitive deionization (CDI) is flourishing as an energy-efficient and cost-effective water desalination method. However, challenges such as electrode degradation and fouling have hindered the practical deployment of CDI technology. To address these challenges, the key point of our strategy is applying a hydrophilic coating composed of polyethylene glycol (PEG)-functionalized nano-TiO2/polyvinylidene fluoride (PVDF) to the electrode interface (labeled as APPT electrode). The PEG/PVDF/TiO2 layer not only mitigates the co-ion depletion, but also imparts the activated carbon (AC) electrode hydrophilicity. As anticipated, the APPT electrode possessed an enhanced desalination capacity of 83.54 µmol g-1 and a low energy consumption of 17.99 Wh m-3 in 10 mM sodium chloride solution compared with the bare AC electrode. Notably, the APPT maintained about 93.19 % of its desalination capacity after 50 consecutive adsorption-desorption cycles in the presence of bovine serum albumin (BSA). During the trial, moreover, no obvious overall performance decline was noted in concentration reduction (Δc), water recovery (WR) and productivity (P) over 50 cycles. This strategy realizes energy-efficient, antifouling and stable brackish water desalination and has great promise for practical applications.

13.
Chemosphere ; 353: 141358, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38311042

RESUMEN

An electrochemical membrane filtration system provides an innovative approach to enhance contaminant removal and mitigate membrane fouling. There is an urgent need to develop portable, versatile, and efficient electrochemical membranes for affordable wastewater treatment. Here, a 3D conductive gradient fiber membrane (CC/PVDF) with a gradient porous structure was prepared using a two-step phase inversion method. Methyl orange (MO) was utilized as model organic substance to investigate the electrochemical performance of the CC/PVDF membrane. At applied potentials of +2 V, +3 V, -2 V and -3 V, the removal efficiency of MO was 5.1, 5.3, 4.8, and 5.1 times higher than at 0 V. A dramatic flux loss of 35.02% occurred on the membrane without electrochemistry, interestingly, whereas the flux losses were only 23.59%-10.24% in the applied potential after 30 min of filtration, which were approximately 1.18, 1.28, 1.29 and 1.38 times as high as that without electrochemistry, respectively. The enhanced removal and anti-fouling performances of the membranes were attributed to the functions of electrochemical degradation, electrostatic repulsion, and electrically enhanced wettability. Electrochemical generation of Hydrogen peroxide, along with HO• radicals, was detected and direct electron transfer and HO• were proved to be the dominant oxidants responsible for MO degradation. The intermediate oxidation products were identified by mass spectrometry, and an electrochemical degradation pathway of MO was proposed based on bond-breaking oxidation, ring-opening reactions, and complete oxidation. All the findings emphasize that the ECMF system possesses superior efficiency and creative potential for water purification applications.


Asunto(s)
Polímeros de Fluorocarbono , Membranas Artificiales , Polivinilos , Purificación del Agua , Electricidad , Conductividad Eléctrica , Electricidad Estática , Purificación del Agua/métodos
14.
Gastroenterol Res Pract ; 2024: 1386147, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39380742

RESUMEN

Purpose: C-reactive protein (CRP) functions as a nonspecific marker in various inflammatory disorders, particularly in evaluating the efficacy of pharmacological treatments in patients with ulcerative colitis. The existing body of evidence does not offer adequate support for the direct implication of CRP in modulating the advancement of ulcerative colitis. Methods: Our study employed a rigorous mouse model. An ulcerative colitis mouse model was established by subjecting CRP-deficient mice to dextran sulfate sodium (DSS) treatment. The phenotype of the mice, which encompassed parameters such as body weight, colon length, and spleen weight, was meticulously evaluated. Additionally, various physiological and biochemical indicators were assessed, including colon histopathology, expression levels of inflammatory factors, and staining of the intestinal mucus layer. Results: The absence of CRP did not significantly affect the phenotype, physiological characteristics, and biochemical indices in a mouse model of ulcerative colitis compared to mice with wild-type CRP. Additionally, eliminating intestinal bacteria flora interference through antibiotic treatment revealed that mice lacking CRP did not demonstrate any notable variations in the ulcerative colitis model. Meanwhile, the survival rate of mice lacking CRP did not exhibit a statistically significant difference compared to wild-type mice. Conclusion: The results of our study suggest that CRP may not directly mediate ulcerative colitis. Instead, it is more likely to be a bystander that is present alongside with elevated inflammatory factors. Further investigation is warranted to determine the precise role of CRP in humans, given the significant limitations associated with the use of mouse models.

15.
Quant Imaging Med Surg ; 13(10): 6446-6455, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37869327

RESUMEN

Background: Ultrasonography has been applied as an alternative method in the assessment of temporomandibular joint (TMJ) pathology including anterior disc displacement (ADD). However, a concrete screening or diagnostic method which is feasible in clinical practice has not yet been established. The study aimed to establish a quantitative ultrasonographic method and determine its diagnostic efficacy for ADD of the TMJ. Methods: A total of 75 joints were allocated to either the normal disc position (NDP) group or the ADD group using magnetic resonance imaging (MRI) as the reference standard. Longitudinal scans of the lateral articular compartment were obtained by a 14-MHz L-shaped linear array transducer. The width of the lateral joint space (LJS), the upper lateral joint space (ULJS), and the lower lateral joint space (LLJS), as well as the position of the lateral articular disc edge (ADE), were investigated by stepwise logistic regression analysis to identify significant indicators of ADD and to build a diagnostic model. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were computed at the optimal cut-off value. Results: MRI detected 25 joints in the NDP group and 50 joints in the ADD group. Correlation analysis indicated that all 4 variables were associated with ADD. With the best performance of the area under the receiver operating characteristic (ROC) curve (AUC) of 0.939, LJS and ULJS were identified as predictors of ADD and subsequently adopted to build a diagnostic model by stepwise logistic regression. The optimal cut-off value of the 2-variable regression model for diagnosing ADD was 0.800, with a sensitivity of 82%, specificity of 96%, PPV of 97.6%, NPV of 72.7%, and an accuracy of 86.7%. Conclusions: The quantitative ultrasonographic diagnostic method showed promising diagnostic efficacy. It has the potential to be used for ADD screening in future clinical practice.

16.
Chemosphere ; 330: 138706, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37068616

RESUMEN

The discharge of oily wastewater has increased dramatically and will bring serious environmental problems. In this work, a self-cleaning and anti-fouling g-C3N4/TiO2/PVDF composite membrane was fabricated via the layer-by-layer approach. The surface of as-prepared composite membrane displayed a superhydrophilic and underwater superoleophobic behavior under irradiation with visible light. Also, upon irradiation with visible light, the fabricated g-C3N4/TiO2/PVDF composite membrane displayed enhanced permeation flux and improved oil removal efficiency as a result of the generation of hydroxyl free radicals during the photocatalytic filtration process. Significantly, irradiation with visible light remarkably improved reusability of the composite membrane by initiating photocatalytic decomposition of deposited oil foulants, which enabled removal of over 99.75% of oils, thus reaching a nearly 100% flux recovery ratio. Furthermore, the g-C3N4/TiO2/PVDF composite membrane exhibited great anti-fouling behavior in photocatalysis-assisted filtration. The mechanistic study revealed that underwater superhydrophobicity and the generation of free hydroxyl radicals jointly contributed to membrane anti-fouling. The greatest advantages of this g-C3N4/TiO2/PVDF composite membrane are that not only does it degrades the oil pollutants, but it also makes the membrane less vulnerable to fouling.


Asunto(s)
Purificación del Agua , Filtración , Aceites , Agua
17.
Chemosphere ; 314: 137545, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36526138

RESUMEN

Membrane fouling and the trade-off between membrane permeability and selectivity restrict the potential applications of membrane filtration for water treatment. ZIF-8 was found having great permeability and antibiofouling performance, but with issue on particle aggregation makes it difficult to achieve high ZIFs loading and fabricate a defect-free molecular sieving membrane in previous research. In this study, we formed a scalable antibiofouling surface with improved permeability and fouling resistance on a PEI-ZIF-PAA membrane using a layer-by-layer assembly technique. The synergistic effects of being sandwiched between two different polyelectrolyte layers with opposite charges endowed the ZIF nanoparticles with improved stability and scalability for membrane modification. The PEI-ZIF-PAA membrane exhibited a satisfactory water flux of 120.78 LMH, which was 46.97% higher than that of the pristine PES membrane. The normalized water flux loss was serious in the absence of ZIF-8, and the flux increased with the ZIF-8 concentration. Antifouling tests suggested that the PEI-ZIF-PAA membrane possessed good antifouling performance due to the much higher surface hydrophilicity and positive Lewis acid-base interactions with foulants. The HA rejection increased with the ZIF-8 concentration and reached a maximum of 92.1% in the presence of 1.00% (w/v) ZIF-8. The membrane regeneration was tested under physical and chemical cleaning with flux recovery rates of about 85% and 95%. XDLVO analysis showed that the total interaction energy between HA and the PEI-ZIF-8-PAA membrane was 26.45 mJ/m2, and the superior antifouling performance was mainly attributed to Lewis acid-base interactions. This study indicates that ZIF-8 nanocrystals are promising materials for fabricating novel membranes for sewage treatment.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Ácidos de Lewis , Membranas Artificiales , Filtración , Interacciones Hidrofóbicas e Hidrofílicas
18.
Adv Sci (Weinh) ; 10(28): e2302813, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37530215

RESUMEN

Memristors with nonvolatile storage performance and simulated synaptic functions are regarded as one of the critical devices to overcome the bottleneck in traditional von Neumann computer architecture. 2D van der Waals heterostructures have paved a new way for the development of advanced memristors by integrating the intriguing features of different materials and offering additional controllability over their optoelectronic properties. Herein, planar memristors with both electrical and optical tunability based on ReS2 /WS2 van der Waals heterostructure are demonstrated. The devices show unique unipolar nonvolatile behavior with high Roff /Ron ratio of up to 106 , desirable endurance, and retention, which are superior to pure ReS2 and WS2 devices. When decreasing the channel length, the set voltage can be notably reduced while the high Roff /Ron ratios are retained. By introducing electrostatic doping through the gate control, the set voltage can be tailored in a wide range from 4.50 to 0.40 V. Furthermore, biological synaptic functions and plasticity, including spike rate-dependent plasticity and paired-pulse facilitation, are successfully realized. By employing optical illumination, resistive switching can also be modulated, which is dependent on the illumination energy and power. A mechanism related to the interlayer charge transfer controlled by optical excitation is revealed.

19.
J Hazard Mater ; 434: 128879, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35427970

RESUMEN

Pharmaceuticals are necessary to be removed from environment. Herein TiO2 incorporated biochar made from pyrolysis of agricultural wastes was encapsulated into chitosan to obtain a novel hydrogel beads. This hydrogel beads executed a dual role as both adsorbent and sonocatalyst, which proved to be suitable for the removal of antibiotic ciprofloxacin (CIP) from water. The results showed that adsorption of CIP followed pseudo first order kinetics model and Langmuir adsorption isotherm model, having maximum adsorption at pH 9. Whereas the degradation was more efficient at pH 6 due to greater standard potential for •OH/H2O in acidic media. The degradation was maximum at 150 W of ultrasonic power, then decreased in presence of dissimilar electrolytes and even reduced to 0 in presence of Na3PO4. Different quenchers such as benzoquinone (BQ), Triethanolamine (TEA) and isopropyl alcohol (IPA) reduced degradation efficiency (DE) and mineralization efficiency (ME). The DE was decreased from 85.23% to 81.50% (BQ), 74.27% (TEA), and 61.77% (IPA) within 25 min. The prepared sonocatalyst was capable of regeneration with DE, remaining sufficiently high (62%) even after four regeneration steps. These results indicate that titanium-biochar/chitosan hydrogel beads (TBCB) are durable and effective for long-term CIP removal.


Asunto(s)
Quitosano , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Ciprofloxacina , Hidrogeles , Concentración de Iones de Hidrógeno , Cinética , Titanio
20.
Cancer Nurs ; 45(2): E573-E581, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33813526

RESUMEN

BACKGROUND: The Chinese government has proposed cancer screening guidelines and launched 2 cancer screening programs to improve screening practices. However, the screening participation rates of Chinese women remain low. Exploring the factors affecting breast cancer screening to promote cancer screening is necessary. OBJECTIVE: The aim of this study was to investigate women's satisfaction with healthcare providers and screening practices. METHODS: A cross-sectional survey was conducted from November 2019 to April 2020 in Changchun, Jilin Province, China. The Medical Care Satisfaction Scale and SERVQUAL were used to quantify women's satisfaction with doctors and nurses, respectively. RESULTS: Women's satisfaction with doctors (68.81 ± 11.08; range, 20-100) and with nurses (87.64 ± 16.17; range, 22-110) was moderate. Compared with women who had not participated in screening within the past 2 years, screened women reported higher satisfaction with doctors (P = .026) and nurses (P = .012). Older age (P = .004) was an independent predictor of women's satisfaction with doctors. Similarly, women's education level (P = .049), chronic disease history (P = .029), and physical examination history (P = .039) were 3 independent predictors of women's satisfaction with nurses. CONCLUSIONS: Future intervention strategies can not only increase the screening rates by providing existing intervention methods but also improve women's satisfaction with healthcare providers to promote screening practices. IMPLICATIONS FOR PRACTICE: This article provides a theoretical basis for healthcare providers to increase female screening practices. It also provides references for improving existing intervention methods.


Asunto(s)
Neoplasias de la Mama , Detección Precoz del Cáncer , Neoplasias de la Mama/diagnóstico , Estudios Transversales , Femenino , Personal de Salud , Humanos , Tamizaje Masivo , Satisfacción Personal , Encuestas y Cuestionarios
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