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1.
Nat Commun ; 15(1): 5375, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918392

RESUMEN

Coupling the Si-based anodes with nickel-rich LiNixMnyCo1-x-yO2 cathodes (x ≥ 0.8) in the energy-dense cell prototype suffers from the mechanical instability of the Li-Si alloys, cathode collapse upon the high-voltage cycling, as well as the severe leakage current at elevated temperatures. More seriously, the cathode-to-anode cross-talk effect of transitional metal aggravates the depletion of the active Li reservoir. To reconcile the cation utilization degree, stress dissipation, and extreme temperature tolerance of the Si-based anode||NMC prototype, we propose a gel polymer electrolyte to reinforce the mechanical integrity of Si anode and chelate with the transitional cations towards the stabilized interfacial property. As coupling the conformal gel polymer electrolyte encapsulation with the spatial arranged Si anode and NMC811 cathode, the 2.7 Ah pouch-format cell could achieve the high energy density of 325.9 Wh kg-1 (based on the whole pouch cell), 88.7% capacity retention for 2000 cycles, self-extinguish property as well as a wide temperature tolerance. Therefore, this proposed polymerization strategy provides a leap toward the secured Li batteries.

2.
ACS Nano ; 18(10): 7596-7609, 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38415583

RESUMEN

The compact design of an environmentally adaptive battery and effectors forms the foundation for wearable electronics capable of time-resolved, long-term signal monitoring. Herein, we present a one-body strategy that utilizes a hydrogel as the ionic conductive medium for both flexible aqueous zinc-ion batteries and wearable strain sensors. The poly(vinyl alcohol) hydrogel network incorporates nano-SiO2 and cellulose nanofibers (referred to as PSC) in an ethylene glycol/water mixed solvent, balancing the mechanical properties (tensile strength of 6 MPa) and ionic diffusivity at -20 °C (2 orders of magnitude higher than 2 M ZnCl2 electrolyte). Meanwhile, cathode lattice breathing during the solvated Zn2+ intercalation and dendritic Zn protrusion at the anode interface are mitigated. Besides the robust cyclability of the Zn∥PSC∥V2O5 prototype within a wide temperature range (from -20 to 80 °C), this microdevice seamlessly integrates a zinc-ion battery with a strain sensor, enabling precise monitoring of the muscle response during dynamic body movement. By employing transmission-mode operando XRD, the self-powered sensor accurately documents the real-time phasic evolution of the layered cathode and synchronized strain change induced by Zn deposition, which presents a feasible solution of health monitoring by the miniaturized electronics.

3.
Pain Res Manag ; 2023: 6433494, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38023825

RESUMEN

Background: Thoracoscopic lung cancer surgery is accompanied by severe pain. Both continuous paravertebral block (CPVB) and continuous wound infiltration (CWI) are widely used for perioperative analgesia in thoracoscopic surgery. However, the effects of these different methods on chronic postsurgical pain (CPSP) are still unknown. Patients and Methods. This prospective randomized controlled trial assessed the eligibility of 113 patients. Ninety-seven patients who met the inclusion criteria were randomly divided into a CPVB group and a CWI group, and 80 patients were analyzed in the final study. The primary outcome measures were the incidence and intensity of chronic postsurgical pain (CPSP) at 3, 6, and 9 months after surgery. The secondary outcome measures were the numerical rating scale (NRS) score of rest and activity at 12, 18, and 24 hours and on the 2nd, 3rd, and 7th days postoperatively; the Barthel Activities of Daily Living (ADL) score of activity levels on the 1st, 2nd, 3rd, and 7th days postoperatively; and the long-term quality of the life score at 3, 6, and 9 months postoperatively. Results: The incidence of chronic postsurgical pain in the CWI group was significantly higher than that in the CPVB group at 3, 6, and 9 months after surgery (all P < 0.05). The intensity of chronic postsurgical pain was significantly decreased in the CPVB group at 3, 6, and 9 months after surgery (P < 0.05). NRS-R and NRS-A scores were significantly decreased in the CPVB group within the first week after thoracoscopic surgery (P < 0.001). ADL scores were increased in the CPVB group within 3 days postoperatively. However, there were no differences in the ADL score on the 7th postoperative day or the long-term quality of the life score at 3, 6, and 9 months postoperatively. Conclusion: Continuous ultrasound-guided paravertebral block reduced the intensity of acute pain within 7 days postoperatively and reduced the incidence of chronic pain at 3, 6, and 9 months after surgery, but there was no significant advantage in long-term quality of life. This trial is registered with ChiCTR2000038505.


Asunto(s)
Neoplasias Pulmonares , Calidad de Vida , Humanos , Incidencia , Estudios Prospectivos , Actividades Cotidianas , Neoplasias Pulmonares/cirugía , Dolor Postoperatorio , Ultrasonografía Intervencional
4.
ACS Nano ; 17(21): 21850-21864, 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37874620

RESUMEN

The scalable development of an environmentally adaptive and homogeneous Li+ supplementary route remains a formidable challenge for the existing prelithiation technologies, restricting the full potential of high-capacity anodes. In this study, we present a moisture-tolerant interfacial prelithiation approach through casting a hydrophobic poly(vinylidene-co-hexafluoropropylene) membrane blended with a deep-lithiated alloy (Li22Si5@C/PVDF-HFP) onto Si based anodes. This strategy could not only extend to various high-capacity anode systems (SiOx@C, hard carbon) but also align with industrial roll-to-roll assembly processes. By carefully adjusting the thickness of the prelithiation layer, the densely packed Si@C electrode (4.5 mAh cm-2) exhibits significantly improved initial Coulombic efficiency until a close-to-unit value, as well as extreme moisture tolerance (60% relative humidity). Furthermore, it achieves more than 10-fold enhancement of ionic conductivity across the electrode. As pairing the prelithiated Si@C anode with the LiNi0.8Co0.1Mn0.1O2 cathode, the 2 Ah pouch-format prototype balances an energy density of ∼371 Wh kg-1 and an extreme power output of 2450 W kg-1 as well as 83.8% capacity retention for 1000 cycles. The combined operando phase tracking and spatial arrangement analysis of the intermediate alloy elucidate that the enhanced Li utilization derives from the gradient stress dissipation model upon a spontaneous Li+ redistribution process.

5.
ACS Nano ; 17(17): 17359-17371, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37607049

RESUMEN

Rechargeable aqueous zinc batteries (RAZBs) represent a sustainable, environmentally benign, cost-efficient energy storage solution for the scaled renewable power system. However, the cycling endurance and temperature adaptability of RAZBs are hindered by practical technological barriers such as the subzero freezing point of aqueous electrolyte, severe cation dissolution of the cathode, and dendrite growth on the Zn anode. Herein, we optimize the hybrid electrolyte formulation of 8 M ZnCl2 in the ethylene glycol-water mixed solvent to reconfigure the hydrogen bonding and [Zn(H2O)1.80(EG)0.23]2+ solvation sheath, which well balances the ionic conductivity and the antifreezing property until -125 °C. As monitored by operando X-ray diffraction, meanwhile, the structural dissolution of the V2O5 cathode upon the dynamic cycling and static idling storage at elevated temperature are effectively restrained. At the anode side, the thermally induced substitution between the Ag2Se overcoating and Zn foil in situ constructs the site-selective, mosaic interface layer, in which the solvophilic ZnSe facilitates the desolvation, while the Ag species provide zincophilic nucleation sites for high-throughput Zn deposition. The synergistic coupling of the antifreezing electrolyte and anode interfacial design enables the wide-temperature-range adaptability of the RAZB prototype (10 µm Zn foil and 1 mAh cm-2 V2O5 cathode), which balances the cycling endurance (92.5% capacity retention rate for 1000 cycles), 84.7% mitigation of the self-discharge rate at 55 °C, as well as the secured cyclability even at -40 °C.

6.
Small ; 19(21): e2207638, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36843222

RESUMEN

Hard carbons (HCs) are extensively investigated as the potential anodes for commercialization of sodium-ion batteries (SIBs). However, the practical deployment of HC anode suffers from the retarded Na+ diffusion at the high-rate or low-temperature operation scenarios. Herein, a multiscale modification strategy by tuning HC microstructure on the particle level as well as replenishing extra Na+ reservoir for the electrode through a homogeneous presodiation therapy is presented. Consequently, the coulombic efficiency of HC anode can be precisely controlled till the close-to-unit value. Detailed kinetics analysis observes that the Na+ diffusivity can be drastically enhanced by two orders of magnitude at the low potential region (< 0.1 V vs. Na+ /Na), which accelerates the rate-limiting step. As pairing the presodiated HC anode (≈5.0 ± 0.2 mg cm-2 ) with the NaVPO4 F cathode (≈10.3 mg cm-2 ) in the 200 mAh pouch cell, the optimal balance of the cyclability (83% over 1000 cycles), low-temperature behavior till -40 °C as well as the maximized power output of 1500 W kg-1 can be simultaneously achieved. This synergistic modification strategy opens a new avenue to exploit the reversible, ultrafast Na+ storage kinetics of HC anodes, which thus constitutes a quantum leap forward toward high-rate SIB prototyping.

7.
Complement Ther Med ; 71: 102900, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36372315

RESUMEN

BACKGROUND: Some adverse events following immunization (AEFI) were observed in potential corelation with COVID-19 vaccination but without prevention or ongoing trial for it. We aimed to investigate efficacy of auricular acupressure (AuriAc) therapy in preventing AEFI after first dosage of the vaccine. METHODS: We performed a multicentre randomized controlled trial with three arms, including AuriAc, SAuriAc (sham auricular acupressure), and TrAsU (treatment as usual) group, carried out in four medical institutions in Chengdu, China, from March 17th to April 23rd, 2021. We enrolled participants based on eligibility criteria and randomized them into three groups: AuriAc (AEFI-specific auricular points applied, n = 52), SAuriAc (n = 51) or TrAsU (n = 44) group. Primary outcomes were percentages of any AEFI and local pain, and secondary outcomes were percentages who reported other AEFI. They were followed at 1, 3, 5, 7, and 14 days, by phone or online, with severity evaluated. RESULTS: 147 participants (73.47% females) were included with median age as 31 years (25-45, IQR). One day after the injection, participants in AuriAc group reported significant reduction on percentages of any AEFI [intention-to-treat, difference of percentage (DP) = -20.13, 95%CI: - 0.39, - 0.02, p = 0.01; per-protocol, DP = -22.21, 95%CI: - 0.40, - 0.03, P = 0.02] and local pain (per-protocol, DP = -18.40, 95%CI: -0.36, -0.01, P = 0.04), compared with TrAsU group. The effects were slight at other follow-up days and for other outcomes, and with a low percentage of mild local allergic reactions. CONCLUSIONS: We firstly explored potential of AuriAc for preventing AEFI related to COVID-19 vaccine injection, which is beneficial for the vaccine recipients, but evidence is limited. TRIAL REGISTRATION: chictr.org.cn no. ChiCTR2100043210 (http://www.chictr.org.cn/showproj.aspx?proj=121519).


Asunto(s)
Acupresión , COVID-19 , Vacunas , Femenino , Humanos , Masculino , Vacunas contra la COVID-19/efectos adversos , COVID-19/prevención & control , Dolor
8.
Artículo en Inglés | MEDLINE | ID: mdl-36193147

RESUMEN

The prevalence of allergic rhinitis (AR) has increased tremendously in the recent year in China. Evidence-based medicine to objectively evaluate the prevalence and risk factors for AR in China is urgently required. Toward this, we systematically searched four English and four Chinese databases to identify the literature on the same, from the year of website establishment until November 2021. A total of 51 studies were evaluated, and data were obtained through Stata 16 analysis. Overall pooled risk factors for adult AR were smoking (odds ratio [OR] = 1.89, 95% confidence interval [CI]: 1.25, 2.87), asthma (OR = 3.30, 95% CI: 1.48, 7.39), a family history of AR (OR = 3.17, 95% CI: 2.31, 4.34), a family history of asthma (OR = 3.99, 95% CI: 2.58, 6.16), drug allergy (OR = 1.62, 95% CI: 1.38, 1.89), food allergy (OR = 2.29, 95% CI: 1.39, 3.78), pollen allergy history (OR = 2.41, 95% CI: 1.67, 3.46), antibiotic use (OR = 2.08, 95% CI: 1.28, 3.36), occupational dust exposure (OR = 2.05, 95% CI: 1.70, 2.47), home renovation (OR = 1.73, 95% CI: 0.99, 3.02), and middle school education (OR = 1.99, 95% CI: 1.29, 3.06). Overall pooled risk factors for AR in children were passive smoking (OR = 1.70, 95% CI: 1.02, 2.82), asthma (OR = 3.26, 95% CI: 2.42, 4.39), a family history of AR (OR = 2.59, 95% CI: 2.07, 3.24), a family history of allergy (OR = 4.84, 95% CI: 3.22, 7.26), a history of allergic diseases (OR = 2.11, 95% CI: 1.52, 2.94), eczema(OR = 2.29, 95% CI: 1.36, 3.85), owning pets (OR = 1.56, 95% CI: 1.37, 1.77), eating seafood (OR = 1.30, 95% CI: 1.10, 1.55), boys (OR = 1.58, 95% CI: 1.43, 1.74), and breastfeeding (OR = 0.82, 95% CI: 0.55, 1.22). The results of our meta-analysis showed that the prevalence of allergy rhinitis was 19% (95% CI 14-25) among adults and 22% (95% CI 17-27) among children, with boys showing a higher prevalence than girls. The development of AR in China is associated with several factors, including allergic diseases (eczema, asthma, pollen allergy, and food allergy), a family history of allergy (AR, asthma, and other allergies), and dwelling and working environment (smoking or passive smoking, occupational dust exposure, and owning pets); conversely, breastfeeding can reduce the risk.

9.
Front Mol Neurosci ; 15: 836534, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35493320

RESUMEN

Postoperative delirium (POD) is a common postoperative complication in elderly patients and seriously affects postoperative recovery. The exact mechanism of POD is still unclear. Therefore, it is necessary to explore the mechanism of POD in transcriptional regulation. At present, circRNAs have been proven to play an important role in a variety of mental health and cognitive disorders, such as Alzheimer's disease, depression and schizophrenia. To reveal the effect of circRNA on POD, we used microarray to analyze the differential expression profiles of circRNAs in the hippocampus of 12-month-old mice between the tibial fracture and control groups. A total of 1,4236 circRNAs were identified. Compared with the control group, there were 500 circRNAs with increased expression and 187 with decreased expression. The accuracy of the microarray data was further verified by qRT-PCR. Finally, GO enrichment and KEGG pathway analyses indicated that changes in axon orientation, ubiquitin-mediated proteolysis, glutamate synapses, the estrogen signaling pathway, the RAS signaling pathway and other systems may be important potential pathological mechanisms in the progression of POD. In particular, we found that the HOMER1 gene and its transcript mmu_circRNA_26701 are specifically expressed in the glutamate synapse, which may provide new clues and intervention targets for the progression of this refractory disease.

10.
ACS Nano ; 16(6): 9117-9129, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35593703

RESUMEN

Featured with an exposed active facet, favorable ion diffusion pathway, and tailorable interfacial properties, low-dimensional structures are extensively explored as alternative electroactive materials with game-changing redox properties. Through a stepwise "proton exchange-insertion-exfoliation" procedure, in this article, we develop Na2Ti6-xMoxO13 (NTMO) nanosheets with weakened out-of-plane bonding and in-plane Mo6+ doping of the tunnel structure. Real-time phase tracking of the laminated NTMO structures upon the lithiation/delithiation process suggests mitigated lattice variation; meanwhile, the kinetics simulation shows a mitigated Li-ion diffusion barrier along the [010] orientation. At an industrial-level areal capacity loading (2.5 mAh cm-2), the NTMO electrode maintains robust cycling endurance (91% capacity retention for 2000 cycles) even at 40 C, as well as the high energy/power densities in the as-constructed NTMO||LiFePO4 full cell prototype. The dimensional and lattice modifications presented in this study thus encourage further exploration of the tailored cation diffusion pathway for the construction of fast-charging batteries.

11.
Trials ; 22(1): 857, 2021 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-34838110

RESUMEN

BACKGROUND: Some pain, fatigue, and gastrointestinal adverse events were observed in potential association with injection of COVID-19 vaccines, while there was no preventive intervention for it. We aim to investigate the efficacy of auricular acupressure (AA) therapy in preventing and relieving AEFI after injection of COVID-19 vaccine. METHODS: The study design is a randomized, multicentre, three-arm controlled, single-blind trial. Participants meeting the inclusion criteria will be advertised and enrolled and assigned in the medical institutions randomly for post-injection observation. No less than 360 participants will be randomized into one of three groups: auricular acupressure group, sham auricular acupressure group, and wait-list group. Interventions will be performed immediately and will happen 4 to 5 times per day for 5 days. The primary clinical outcomes will be quality and quantity evaluation among participants who reported any AEFI and who reported local pain at injection site. Secondary outcomes will concern headache, muscle and (or) joint pain, fatigue, nausea, vomiting, diarrhoea, and other potential events. All the outcomes will be assessed at baseline and 1, 3, 5, 7, and 14 days after the injection. Both intention-to-treat and per-protocol analyses will be performed, with significance level determined as 5%. DISCUSSION: Results of this trial will help to clarify the value of auricular acupressure therapy in preventing and relieving overall and certain adverse events following immunization after injection of COVID-19 vaccine. TRIAL REGISTRATION: China Clinical Trial Registry (ChiCTR) ( ChiCTR2100043210 ). Registered on 8 February, 2021.


Asunto(s)
Acupresión , COVID-19 , Vacunas contra la COVID-19 , Humanos , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2 , Método Simple Ciego , Resultado del Tratamiento , Vacunación
12.
Adv Sci (Weinh) ; 8(23): e2102053, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34665530

RESUMEN

Aqueous V2 O5 -Zn batteries, an alternative chemistry format that is inherently safer to operate than lithium-based batteries, illuminates the low-cost deployment of the stationary energy storage devices. However, the cathode structure collapse caused by H2 O co-insertion in aqueous solution dramatically deteriorates the electrochemical performance and hampers the operation reliability of V2 O5 -Zn batteries. The real-time phase tracking and the density functional theory (DFT) calculation prove the high energy barrier that inhibits the Zn2+ diffusion into the bulk V2 O5 , instead the ZnCl2 "water-in-salt electrolyte" (WiSE) can enable the dominant proton insertion with negligible lattice strain or particle fragment. Thus, ZnCl2 WiSE enables the enhanced reversibility and extended shelf life of the V2 O5 -Zn battery upon the high temperature storage. The improved electrochemical performance also benefits by the inhibition of vanadium cation dissolution, enlarged voltage window, as well as the suppression of the Zn dendrite protrusion. This study comprehensively elucidates the pivotal role of a concentrated ZnCl2 electrolyte to stabilize the aqueous batteries at both the static storage and dynamic operation scenarios.

13.
Trials ; 22(1): 162, 2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33632286

RESUMEN

OBJECTIVES: To investigate if traditional Chinese medicine (TCM) auricular point acupressure (APA) can alleviate and (or) reduce the pain (including injection site pain, headache, other muscle and joint pain), fatigue, and gastrointestinal adverse reactions (including nausea, vomiting, diarrhea), after the injection of novel coronavirus-19 vaccines (NCVs). TRIAL DESIGN: The study is designed as a multicentre, parallel-group, three-arm, single-blind, prospective, randomized (1:1:1 ratio) study. PARTICIPANTS: More than 360 participants will be recruited from healthy people who vaccinate NCVs in 5 community healthcare centres in the Sichuan province of China and 1 university hospital (Hospital of Chengdu University of Traditional Chinese Medicine). INCLUSION CRITERIA: ①Vaccinators meets the conditions of NCVs injection and have no contraindications to it. The details shall be subject to the instructions of the NCVs used and the statement of medical institutions. The first dose of NCVs injection shall be completed within 24 hours from the time of injection to the time of enrolment; ②No redness, swelling, injury or infection of the skin or soft tissue of both ears, which is not suitable for APA; ③No history of alcohol and adhesive tape contact allergy; ④18-59 years old, regardless of gender; ⑤Those who were able to complete the questionnaire independently at the time of the first and second dose of NCVs and on the 3rd, 7th and 15th day after the first and second dose of NCVs respectively; ⑥Those who agree to participate in the trial and sign the informed consent, and can seriously abide by the precautions after the injection of NCVs and the requirements of traditional Chinese medicine auricular point plasters sticking and acupressure. EXCLUSION CRITERIA: ①Those who are not suitable to be vaccinated because they belong to the contraindication or cautious population; ②Those who have participated in other clinical trials within 4 weeks before the start of this study; ③No chronic/habitual/persistent headache, Muscle or joint pain, fatigue, diarrhea, nausea, retching or vomiting before the injection of NCVs, and no related diseases present (details of this item is listed in full protocol); ④Those who are in use or have received TCMAPA within 2 weeks before the trial; ⑤Pregnant or lactating women; ⑥Participants with other serious primary diseases and psychosis. INTERVENTION AND COMPARATOR: ①Auricular point acupressure group: participants receive bilateral, symptom-specific TCMAPA in 5 auricular points (per side, 10 points bilateral) for 5 days, 3-4 times (about 1 min each time) of self-acupressure per day, after each NCVs injection (10 days in total). ②Sham auricular point acupressure group: participants receive bilateral, none symptom-specific, sham APA in 5 auricular points (per side, 10 points bilateral) for 5 days, 3-4 times (about 1 min each time) of self-acupressure per day, after each NCVs injection (10 days in total). ③Blank control group: Non-intervention blank control. The Hebei medical device Co. Ltd, Hebei, China manufactured the auricular point sticking plasters. MAIN OUTCOMES: Primary outcomes are all scores of visual analogue scale (VAS) based on subjective judgment of the participants included, including VAS score of pain at injection site, headache, muscle and joint pain, fatigue, nausea, retching, vomiting and diarrhea. Time points for outcomes above are the same: ①Immediately after first and second injection of the vaccine (Baseline assessment); ②Three days after first and second injection of the vaccine; ③Seven days after first and second injection of the vaccine; ④Fifteen days after first and second injection of the vaccine. RANDOMISATION: Participants will be randomized in 1:1:1 ratio to each group by computerized random number generator, and independently in each sub-centre. BLINDING (MASKING): Participants, information collectors and statistical evaluators will be blinded between APA group and sham APA group. No blinding in the control group. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): No less than 360 participants will be randomized in 1:1:1 ratio to each group. TRIAL STATUS: Protocol version 2.0 of February 3rd, 2021. Recruitment is expected to start on February 18th, 2021, and to finish on March 12th, 2021. TRIAL REGISTRATION: This trial was registered in the China Clinical Trial Registry (ChiCTR) ( ChiCTR2100043210 ) on 8th February, 2021. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.


Asunto(s)
Acupresión , Vacunas contra la COVID-19/efectos adversos , Fatiga/prevención & control , Enfermedades Gastrointestinales/prevención & control , Reacción en el Punto de Inyección/prevención & control , Dolor/prevención & control , Vacunación/efectos adversos , Puntos de Acupuntura , Adolescente , Adulto , Vacunas contra la COVID-19/administración & dosificación , China , Pabellón Auricular , Fatiga/etiología , Femenino , Enfermedades Gastrointestinales/etiología , Humanos , Reacción en el Punto de Inyección/etiología , Inyecciones Intramusculares , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Dolor/etiología , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple Ciego , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
14.
Nanoscale ; 12(39): 20131-20140, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32749438

RESUMEN

The direct esterification of CO involves processes using CO as the starting material and ester chemicals as products. Dimethyl oxalate (DMO) and dimethyl carbonate (DMC) are two different products of the direct CO esterification reaction. However, the effective control of the reaction pathway and direct synthesis of DMO and DMC are challenging. In this review, we summarize the recent research progress on the direct esterification of CO to DMO/DMC and reveal the functional motifs responsible for the catalytic selectivity. Firstly, we discuss the microstructure of catalysts for the direct esterification of CO to DMO and DMC, including the valence state and the aggregate state of Pd. Then, the influence of characteristics of the support on the selectivity is analyzed. Importantly, the aggregate state of the active component, Pd is deemed as a vital functional motif for catalytic selectivity. The isolated Pd is conducive for the formation of DMC, while the aggregated Pd is beneficial for the formation of DMO. This review will provide rational guidance for the direct esterification of CO to DMO and DMC.

15.
Sci Total Environ ; 748: 141536, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32798881

RESUMEN

The dispersities of goethite nanoparticles (GTNPs) and ferrihydrite nanoparticles (FHNPs) affect the transport and retention of nanoparticle-associated contaminants. However, the effects of interaction on nanoparticle stability under varying environmental conditions have not been previously investigated. This study utilized settling experiments, a semi-empirical model, and the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory to study the homo-aggregation and hetero-aggregation of GTNPs and FHNPs. The pure system of GTNPs tended to aggregate more easily than that of FHNPs, especially under the conditions of high pH (7.0-9.0), high ionic strength (IS, 10 mM), and low concentrations of humic acid (HA) (2 mg L-1). This aggregation was attributed to the elongated morphology of GTNPs, which contributed to surface heterogeneity. The GTNPs and FHNPs mixtures rapidly coagulated, particularly under the surface-charge disequilibrium caused by an increase in negative charges or IS. Hetero-aggregation increased with increase in the GTNPs ratio, indicating that the elongated GTNPs dominated the coagulation of the Fe mineral nanoparticle mixture, which was attributed to the surface heterogeneity and high probability collisions between the GTNPs. Although DLVO neglects the influence of heterogeneity on the nanoparticle surfaces, SEM revealed that hetero-aggregation of GTNPs and FHNPs occurred. The results obtained in this study provide novel and valuable insights into the behaviors of GTNPs and FHNPs mixtures and suggest that during the gradual transformation of FHNPs to GTNPs in soil or aquatic environments, the hetero-aggregation of GTNPs and FHNPs may be enhanced, thus promoting contaminant immobilization.

16.
Nanoscale ; 12(27): 14825-14830, 2020 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-32672320

RESUMEN

Pd-Based heterogeneous catalysts have been demonstrated to be efficient in numerous heterogeneous reactions. However, the effect of the support resulting in covalent metal-support interaction (CMSI) has not been researched sufficiently. In this work, a Lewis base is modulated over MgAl-LDH to investigate the support effects and it is further loaded with Pd clusters to research the metal-support interactions. MgAl-LDH with ultra-low Pd loading (0.0779%) shows CO conversion (55.0%) and dimethyl oxalate (DMO) selectivity (93.7%) for CO oxidative coupling to DMO, which was gradually deactivated after evaluation for 20 h. To promote the stability of Pd/MgAl-LDH, Zn2+ ions were introduced into the MgAl-LDH support to strengthen the CMSI by forming Pd-Zn bonds, which further increased the adsorption energy of the Pd clusters on ZnMgAl-LDH, and this was verified by X-ray absorption fine structure (XAFS) measurements and density functional theory (DFT) calculations. The stability of the Pd/ZnMgAl-LDH catalyst could be maintained for at least 100 h. This work highlights that covalent metal-support interactions can be strengthened by forming new metal-metal bonds, which could be extended to other systems for the stabilization of noble metals over supports.

17.
Huan Jing Ke Xue ; 41(5): 2292-2300, 2020 May 08.
Artículo en Chino | MEDLINE | ID: mdl-32608847

RESUMEN

Agglomeration and dispersion of nanoparticles control many important environmental processes. In this study, the particle size and zeta potential of ferrihydrite nanoparticles (FHNPs) and goethite nanoparticles (GTNPs) under different pH, ion, and organic matter conditions were measured. These data were used to calculate the Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction energy between nanoparticles to further investigate the stability of two nanoparticles. The results showed that Na+ and Ca2+ promoted FHNPs and GTNPs agglomeration due to their ionic strength. The PO43- with low-concentration (2 mmol·L-1), humic acid and fulvic acid (2 mg·L-1 and 10 mg·L-1) loaded on iron mineral nanoparticles changed their surface charge and further improved the stability of FHNPs and GTNPs at medium and high pH. Although the PO43- with high concentration (10 mmol·L-1) also changed the electrical properties of iron mineral nanoparticles, it had little contribution to the GTNP stability due to its ionic strength. When the zeta potentials of FHNPs or GTNPs were close to 0, the primary barrier and secondary minima were nonexistent simultaneously. The two kinds of nanoparticles irreversibly agglomerated in primary minima. When the primary barrier and secondary minima coexisted, the proportion of reversible aggregation of FHNPs and GTNPs in secondary minima increased. The results provided support for further investigation of the environmental behavior of FHNPs and GTNPs, and iron mineral nanoparticle-facilitated transport of pollutants.

18.
Chem Commun (Camb) ; 56(3): 403-406, 2020 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-31821392

RESUMEN

CeO2-x quantum dots with massive oxygen vacancies are obtained by a one-step single molecular synthesis strategy. The yield of dimethyl carbonate from CO2 and methanol is more than 5 times that for commercial CeO2 nanoparticles.

19.
Nucleic Acids Res ; 47(14): 7580-7591, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31147722

RESUMEN

Alternative cleavage and polyadenylation (APA) can occur at more than half of all human genes, greatly enhancing the cellular repertoire of mRNA isoforms. As these isoforms can have altered stability, localisation and coding potential, deregulation of APA can disrupt gene expression and this has been linked to many diseases including cancer progression. How APA generates cancer-specific isoform profiles and what their physiological consequences are, however, is largely unclear. Here we use a subcellular fractionation approach to determine the nuclear and cytoplasmic APA profiles of successive stages of colon cancer using a cell line-based model. Using this approach, we show that during cancer progression specific APA profiles are established. We identify that overexpression of hnRNPC has a critical role in the establishment of APA profiles characteristic for metastatic colon cancer cells, by regulating poly(A) site selection in a subset of genes that have been implicated in cancer progression including MTHFD1L.


Asunto(s)
Empalme Alternativo , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética , Neoplasias/genética , Poliadenilación , Isoformas de ARN/genética , Aminohidrolasas/genética , Aminohidrolasas/metabolismo , Línea Celular Transformada , Línea Celular Tumoral , Neoplasias del Colon/genética , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Progresión de la Enfermedad , Formiato-Tetrahidrofolato Ligasa/genética , Formiato-Tetrahidrofolato Ligasa/metabolismo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Ribonucleoproteína Heterogénea-Nuclear Grupo C/metabolismo , Humanos , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Neoplasias/metabolismo , Neoplasias/patología , Poli A/genética , Poli A/metabolismo , Interferencia de ARN
20.
Mikrochim Acta ; 186(4): 241, 2019 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-30868262

RESUMEN

The activity of terminal deoxynucleotidyl transferase (TdTase) is a biomarker for routine diagnosis of acute leukemia. A method has been developed for the determination of TdTase activity. It is based on the use of silver nanoclusters (AgNCs) whose yellow fluorescence is enhanced by an in-situ grown DNA tail of TdTase-polymerized and guanine-rich DNA at the 3' end of a hairpin DNA. The fluorescence, best measured at excitation/emission peaks of 530/585 nm, increases linearly in the 1 to 35 mU mL-1 TdTase activity range. The detection limit is 0.8 mU mL-1. The method is cost-efficient, selective and convenient. It integrates enhancement of the fluorescence of AgNCs and target recognition into a single process. Graphical abstract Schematic presentation of a method for determination of TdTase activity. It is based on AgNCs fluorescence enhanced by in-situ grown TdTase-polymerized G-rich DNA tail. The method integrates AgNCs fluorescence enhancement and the target recognition into a single process.


Asunto(s)
ADN Nucleotidilexotransferasa/sangre , ADN/química , Pruebas de Enzimas/métodos , Nanopartículas del Metal/química , Secuencia de Bases , Biomarcadores/sangre , Técnicas Biosensibles/métodos , ADN/genética , Fluorescencia , Humanos , Secuencias Invertidas Repetidas , Leucemia/diagnóstico , Límite de Detección , Plata/química , Espectrometría de Fluorescencia/métodos
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