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1.
BMJ Open ; 14(5): e079167, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724047

RESUMO

INTRODUCTION: The 2020 American Heart Association guidelines encourage lay rescuers to provide chest compression-only cardiopulmonary resuscitation to simplify the process and encourage cardiopulmonary resuscitation initiation. However, recent clinical trials had contradictory results about chest compression-only cardiopulmonary resuscitation. This study will aim to compare standard and chest compressions-only cardiopulmonary resuscitation after out-of-hospital cardiac arrest. METHODS AND ANALYSIS: This study will retrieve only randomised and quasi-randomised controlled trials from the Cochrane Library, PubMed, Web of Science and Embase databases. Data on study design, participant characteristics, intervention details and outcomes will be extracted by a unified standard form. Primary outcomes to be assessed are hospital admission, discharge, and 30-day survival, and return of spontaneous circulation. The Grading of Recommendations, Assessment, Development and Evaluation framework will evaluate the quality of evidence. Cochrane's tool for assessing the risk of bias will evaluate risk deviation. If the I2 statistic is lower than 40%, the fixed-effects model will be used for meta-analysis. Otherwise, the random-effects model will be used. The search will be performed following the publication of this protocol (estimated to occur on 30 December 2024). DISCUSSION: This study will evaluate the effect of chest compression-only cardiopulmonary resuscitation after out-of-hospital cardiac arrest and provide evidence for cardiopulmonary resuscitation guidelines. ETHICS AND DISSEMINATION: No patient or public entity will be involved in this study. Therefore, the study does not need to be ethically reviewed. The results of the study will be disseminated through peer-reviewed journal publications and committee conferences. PROSPERO REGISTRATION NUMBER: CRD42021295507.


Assuntos
Reanimação Cardiopulmonar , Metanálise como Assunto , Parada Cardíaca Extra-Hospitalar , Revisões Sistemáticas como Assunto , Parada Cardíaca Extra-Hospitalar/terapia , Parada Cardíaca Extra-Hospitalar/mortalidade , Humanos , Reanimação Cardiopulmonar/métodos , Projetos de Pesquisa , Ensaios Clínicos Controlados Aleatórios como Assunto , Massagem Cardíaca/métodos , Massagem Cardíaca/normas
2.
Nat Mater ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684883

RESUMO

For halide perovskites that are susceptible to photolysis and ion migration, iodide-related defects, such as iodine (I2) and iodine vacancies, are inevitable. Even a small number of these defects can trigger self-accelerating chemical reactions, posing serious challenges to the durability of perovskite solar cells. Fortunately, before I2 can damage the perovskites under illumination, they generally diffuse over a long distance. Therefore, detrimental I2 can be captured by interfacial materials with strong iodide/polyiodide (Ix-) affinities, such as fullerenes and perfluorodecyl iodide. However, fullerenes in direct contact with perovskites fail to confine Ix- ions within the perovskite layer but cause detrimental iodine vacancies. Perfluorodecyl iodide, with its directional Ix- affinity through halogen bonding, can both capture and confine Ix-. Therefore, inverted perovskite solar cells with over 10 times improved ultraviolet irradiation and thermal-light stabilities (under 85 °C and 1 sun illumination), and 1,000 times improved reverse-bias stability (under ISOS-V ageing tests) have been developed.

3.
ACS Appl Mater Interfaces ; 16(10): 13202-13211, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38438319

RESUMO

Quartz is a key raw material in high-tech fields (such as photovoltaics and semiconductor microelectronics), and the most efficient extraction method of quartz is mineral flotation. Quartz activation plays a crucial role in mineral flotation. However, the mechanism underlying the process remains unclear, and the role of additional metal ions is controversial. In this study, the interaction forces between the quartz surface, the dodecylamine (DDA) cation/sodium oleate (NaOL) anion mixed collectors, and Ca2+ were analyzed using atomic force microscopy in order to systematically explore the activation process of quartz flotation. The results confirmed that the activation process was initialized from NaOL, which was adsorbed on the surface of a calcium-covered quartz surface. The existence of DDA inhibited the binding of Ca2+ to NaOL so that more Ca2+ was adsorbed on the quartz surface to provide the adsorption site for NaOL. Moreover, the best adsorption condition of Ca2+ + NaOL + DDA mixed solution was analyzed by quartz crystal microbalance with dissipation, and it demonstrated that the most stable chemisorption environment on the quartz surface was at pH 11.0. In these circumstances, Ca2+ could first adsorb in a point-like manner on the quartz surface, which was then adsorbed with a mixture of NaOL and DDA. This result showed that, at a specific pH, Ca2+ could encourage the coadsorption of cationic/anionic mixed collectors on quartz. This work provides an important new understanding of the intermolecular interactions that take place during complex mineral flotation processes between chemical additives and mineral surfaces. The methodology used in this study can be easily adapted to different interfacial processes, including water treatment, membrane technology, bioengineering, and oil production.

4.
Adv Mater ; 36(18): e2309844, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38227203

RESUMO

Metal halide perovskite solar cells (PSCs) have garnered much attention in recent years. Despite the remarkable advancements in PSCs utilizing traditional metal electrodes, challenges such as stability concerns and elevated costs have necessitated the exploration of innovative electrode designs to facilitate industrial commercialization. Herein, a physically and chemically stable molybdenum (Mo) electrode is developed to fundamentally tackle the instability factors introduced by electrodes. The combined spatially resolved element analyses and theoretical study demonstrate the high diffusion barrier of Mo ions within the device. Structural and morphology characterization also reveals the negligible plastic deformation and halide-metal reaction during aging when Mo is in contact with perovskite (PVSK). The electrode/underlayer junction is further stabilized by a thin seed layer of titanium (Ti) to improve Mo film's uniformity and adhesion. Based on a corresponding p-i-n PSCs (ITO/PTAA/PVSK/C60/SnO2/ITO/Ti/Mo), the champion sample could deliver an efficiency of 22.25%, which is among the highest value for PSCs based on Mo electrodes. Meanwhile, the device shows negligible performance decay after 2000 h operation, and retains 91% of the initial value after 1300 h at 50-60 °C. In summary, the multilayer Mo electrode opens an effective avenue to all-round stable electrode design in high-performance PSCs.

5.
Phys Chem Chem Phys ; 26(6): 5027-5037, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38258478

RESUMO

Organometal halide perovskites are promising materials for optoelectronic applications, whose commercial realization depends critically on their stability under multiple environmental factors. In this study, a methylammonium lead bromide (MAPbBr3) single crystal was cleaved and exposed to simultaneous oxygen and light illumination under ultrahigh vacuum (UHV). The exposure process was monitored using X-ray photoelectron spectroscopy (XPS) with precise control of the exposure time and oxygen pressure. It was found that the combination of oxygen and light accelerated the degradation of MAPbBr3, which could not be viewed as a simple addition of that by oxygen-only and light-only exposures. The XPS spectra showed significant loss of carbon, bromine, and nitrogen at an oxygen exposure of 1010 Langmuir with light illumination, approximately 17 times of the additive effects of oxygen-only and light-only exposures. It was also found that the photoluminescence (PL) emission was much weakened by oxygen and light co-exposure, while previous reports had shown that PL was substantially enhanced by oxygen-only exposure. Measurements using a scanning electron microscope (SEM) and focused ion beam (FIB) demonstrated that the crystal surface was much roughened by the co-exposure. Density functional theory (DFT) calculations revealed the formation of superoxide and oxygen induced gap state, suggesting the creation of oxygen radicals by light illumination as a possible microscopic driving force for enhanced degradation.

6.
Small Methods ; 8(1): e2300716, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37732360

RESUMO

"Perovskite/carbon" interface is a bottle-neck for hole-conductor-free, carbon-electrode basing perovskite solar cells due to the energy mismatch and concentrated defects. In this article, in-situ healing strategy is proposed by doping octylammonium iodide into carbon paste that used to prepare carbon-electrode on perovskite layer. This strategy is found to strengthen interfacial contact and reduce interfacial defects on one hand, and slightly elevate the work function of the carbon-electrode on other hand. Due to this effect, charge extraction is accelerated, while recombination is obviously reduced. Accordingly, power conversion efficiency of the hole-conductor-free, planar perovskite solar cells is upgraded by ≈50%, or from 11.65 (± 1.59) % to 17.97 (± 0.32) % (AM1.5G, 100 mW cm-2 ). The optimized device shows efficiency of 19.42% and open-circuit voltage of 1.11 V. Meanwhile, moisture-stability is tested by keeping the unsealed devices in closed chamber with relative humidity of 85%. The "in-situ healing" strategy helps to obtain T80 time of >450 h for the carbon-electrode basing devices, which is four times of the reference ones. Thus, a kind of "internal encapsulation effect" has also been reached. The "in situ healing" strategy facilitates the fabrication of efficient and stable hole-conductor-free devices basing on carbon-electrode.

7.
Int Emerg Nurs ; 71: 101356, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37972518

RESUMO

BACKGROUND: Emergency specialist nurses play a vital role in providing high-quality care to patients. This study investigated the innovative behavior and information literacy of emergency specialist nurses and analyzed the influence of information literacy on innovative behavior to promote the latter. METHODS: In total, 484 emergency specialist nurses in Sichuan Province, China, completed the Innovative Behavior and Information Literacy Scales. Univariate analysis, Pearson's analysis, and multiple linear regression were performed. RESULTS: The emergency specialist nurses' innovative behavior and information literacy scores were 32.34 ± 6.27 and 74.32 ± 7.38, respectively. Scores for information awareness, ability, knowledge, and ethics were 3.90 ± 0.53, 2.95 ± 0.45, 3.32 ± 0.19, and 3.28 ± 0.30, respectively. The correlation analysis demonstrated that information literacy positively correlated with innovative behavior. The multivariate linear regression analysis revealed that experience in publishing academic papers influenced innovative behavior. CONCLUSIONS: Emergency specialist nurses demonstrated a moderate level of innovative behavior. Higher information literacy was associated with higher innovative behavior. Therefore, enhancing emergency specialist nurses' information literacy could stimulate innovative behavior and improve innovation ability. Nursing managers should develop corresponding information literacy training programs according to the characteristics of information literacy and evidence-based practice of emergency specialist nurses to improve their innovation level and quality of specialized nursing services.


Assuntos
Competência em Informação , Enfermeiras e Enfermeiros , Humanos , Estudos Transversais , China , Inquéritos e Questionários
8.
J Mater Chem B ; 11(41): 10029-10042, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37850311

RESUMO

Collagen and hyaluronic acid are commonly applied in cartilage tissue engineering, yet there has been limited investigation into their inflammatory response, a crucial factor in articular cartilage repair. This study aimed to evaluate the impact of components and physical properties of hydrogels on inflammatory response and cartilage repair. Three kinds of hydrogels with comparable storage moduli at low frequencies were designed and fabricated, namely, methacrylic anhydride-modified hyaluronic acid hydrogel (HAMA), methacrylic anhydride-modified type I collagen hydrogel (CMA) and unmodified type I collagen hydrogel (Col). HAMA hydrogel was unfavorable for adhesion and spreading of BMSCs. Furthermore, HAMA hydrogel stimulated rapid migration and pro-inflammatory M1 polarization of macrophages, leading to persistent and intense inflammation, which was unfavorable for cartilage repair. CMA and Col hydrogels possessed the same component and facilitated the adhesion, spreading and proliferation of BMSCs. Compared with CMA hydrogel, Col hydrogel induced rapid migration and moderate M1 polarization of macrophages at the early stage of injury, which was mainly influenced by its fast dissolution rate, small pore size fiber network structure and rapid stress relaxation. In addition, the phenotype of macrophages timely transformed into anti-inflammatory M2 due to the properties of the collagen component, which shortened the duration of inflammation and enhanced cartilage repair. The results indicated that moderate macrophage activation adjusted by hydrogel components and physical properties was critical in modulating inflammation and cartilage regeneration.


Assuntos
Cartilagem Articular , Hidrogéis , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Condrócitos , Ácido Hialurônico/farmacologia , Ácido Hialurônico/química , Colágeno Tipo I , Colágeno/química , Inflamação/tratamento farmacológico , Anidridos
9.
Ther Clin Risk Manag ; 19: 783-799, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37850070

RESUMO

Background: Fluid resuscitation is routinely needed for critically ill patients. However, the optimal choice between crystalloids and normal saline is in heat debate. Objective: To conduct a meta-analysis comparing normal saline and balanced crystalloids in the treatment of critically ill patients with composite mortality as the primary outcome. Methods: PubMed, Embase, Medline, Web of Science, and Cochrane Library were searched from inception up to March 2022. Studies of critically ill adult patients assigned to receive normal saline or balanced crystalloids were included. We conducted a meta-analysis using an inverse variance, random-effects model in addition to trial sequential analysis (TSA). The primary outcome was composite mortality. Subgroup analyses were also conducted. Results: Eighteen full-text studies (n=36,224) were included. Balanced crystalloids were associated with lower mortality compared with normal saline (risk ratio [RR]=0.96; 95% confidential interval [CI] 0.93, 1; p=0.03; I2=0) and lower incidence of acute kidney injury/acute renal failure (RR =0.93; 95% CI = 0.87, 0.99; p=0.03). No significant difference was observed in other outcomes. In the sepsis patients, the balanced crystalloid showed a lower composite mortality rate compared with normal saline (RR =0.91; 95% CI = 0.85, 0.99; p=0.02). TSA analysis demonstrated that, with 80% power, the effect of balanced crystalloid is not larger than a 10% relative decrease in composite mortality compared with normal saline. Conclusion and Relevance: This study demonstrated that balanced crystalloids could be an optimal choice over normal saline in critically ill patients to a reduced composite mortality rate. In patients with sepsis, the difference is especially significant. Nonetheless, the optimal resuscitation fluid option between saline and balanced crystalloid solutions should be investigated further with more evidence.

10.
Nurs Crit Care ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37905383

RESUMO

OBJECTIVE: To identify the validity and predictability of the confusion assessment method for the intensive care unit (CAM-ICU) for delirium in critically ill patients in the ICU. METHODS: In this systematic review, PubMed, Embase, Cochrane Central Register of Controlled Trials, and MEDLINE databases were searched for observational studies investigating delirium screening tools for ICU patients. In the meta-analysis, we combined the sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and area under the curve (AUC) of SROC to analysis the predictive value of CAM-ICU. RESULTS: Twenty-nine articles met the inclusion criteria. The pooled sensitivity and specificity values were 0.82 (95% confidence interval [CI]: 0.75-0.87) and 0.95 (95% CI: 0.93-0.97), respectively. The AUC point estimate of the SROC curve was 0.96 (95% CI: 0.94-0.97). Race (Asian or Others) could affect the pooled sensitivity and specificity, and the analysis method (Patient- or Scan-based) and study design were not sources of heterogeneity for pooled sensitivity and specificity. CONCLUSIONS: The CAM-ICU is a valid and reliable tool for delirium prediction among ICU patients. When introducing CAM-ICU to assess delirium, it is necessary to localize its language and content to improve its predictive efficacy in different countries and different ethnic groups. RELEVANCE TO CLINICAL PRACTICE: In clinical practice, nurses can use CAM-ICU to evaluate delirium in critically ill patients in ICU. However, it is necessary to debug the language and content according to the application population.

11.
J Phys Chem C Nanomater Interfaces ; 127(39): 19599-19606, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37817921

RESUMO

In this study, a facile passivation for methylammonium lead bromide (MAPbBr3) single crystals is reported. Stability against moisture and light remains the most critical demerit of perovskite materials, which is improved by depositing a 40 Å thick hydrophobic copper phthalocyanine (CuPc) layer on top of the cleaved perovskite surface. The water and light exposure processes were monitored with X-ray photoelectron spectroscopy with precise control of the exposure time and pressure. It is found that the CuPc top layer could protect the sample from moisture infiltration at a water exposure of 1013 L, while the nonpassivated sample started to degrade at 108 L. During the light exposure, CuPc also slowed down the light-induced degradation, which is supported by the elemental ratio change of metallic lead and bromine. These results are further confirmed by the morphological comparison via scanning electron microscopy and focused ion beam.

12.
Am J Emerg Med ; 73: 131-136, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37657142

RESUMO

OBJECTIVES: Older patients arrive at the emergency department (ED) with complex medical challenges, and the current ED triage models frequently undertriage the severity of illness in older adults. There is increasing awareness regarding the importance of identifying frailty in older patients in the context of urgent care. Therefore, this study aimed to assess the predictive accuracy of the seven-question tool of the Program on Research for Integrating Services of the Maintenance of Autonomy (PRISMA-7) in the ED for 28-day mortality among older adults. DESIGN: A prospective polycentric observational study. SETTING: West China Hospital of Sichuan University, Shangjinnanfu of West China Hospital, and People's Hospital of Henan Province. PARTICIPANTS: ED patients aged ≥65 years from the three tertiary care centers over an 8-week period. PRIMARY AND SECONDARY OUTCOMES: The primary outcome, 28-day all-cause mortality, was investigated using a Cox proportional hazards regression model to assess the predictive validity. The secondary endpoints, intensive care unit (ICU) transfer was investigated using multivariable logistic regression, compared with trained study assistants. RESULTS: The final study population comprised 1043 consecutive patients aged ≥65 years. The area under the receiver operating characteristic (ROC) curve (AUC) for 28-day mortality was 0.80 (95% confidence interval [CI]: 0.76-0.84), 0.73 (95% CI: 0.68-0.77), and 0.78 (95% CI: 0.73-0.83) for PRISMA-7, Emergency Severity Index (ESI), and quick Sepsis Related Organ Failure Assessment (qSOFA), respectively.There was no difference in the AUC between PRISMA-7 and qSOFA(p = 0.374).The AUC for ICU admission was 0.78 (95% CI: 0.75-0.80), 0.62 (95% CI: 0.59-0.66), and 0.68 (95% CI: 0.64-0.72) for PRISMA-7, ESI, and qSOFA, respectively.The AUC for ICU admission between PRISMA-7 and ESI(p<0.001), PRISMA-7 and qSOFA(p<0.001), qSOFA and ESI(p = 0.005) was statistically significant. CONCLUSION: Our findings reveal that PRISMA-7 improves the prediction of ICU admission, but there is no significant difference when it comes to all-cause mortality. PRISMA-7 appears to be a reliable and valid instrument for identifying frailty in the ED. TRIAL REGISTRATION NUMBER: ChiCTR2100046545.

13.
Inquiry ; 60: 469580231163089, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37070701

RESUMO

The Surprise Question is an effective tool to identify patients in need of palliative care. But it is unknown whether the Surprise Question can effectively predict adverse outcomes in Emergency patients. Therefor this study is to determine the utility of the modified Surprise Question for risk stratification in emergency patients. And assessed if the modified Surprise Question could be used by different healthcare personnel. Nurses and patients' families were asked to respond as "Yes" or "No" to the modified Surprise Question for each patient. The outcome was resuscitation unit admission. Logistic regression was used to determine covariant significantly associated with resuscitation unit admission. The area under the curve for the second Surprise Question response by nurses was 0.620, which improved to 0.704 when the responses of nurses and patients' families were in agreement. The clinical impression of nurses is a valuable tool to predict altered conditions for medium-acuity patients, and the diagnostic accuracy improves when responses of patients' families and nurses agreed. The clinical impression of nurses is a valuable tool to predict altered conditions for medium-acuity patients, and the diagnostic accuracy improves when responses of patients' families and nurses agreed.


Assuntos
Enfermeiras e Enfermeiros , Cuidados Paliativos , Humanos , Estudos Prospectivos , Prognóstico , Medição de Risco
14.
J Mater Chem B ; 11(18): 4050-4064, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37078118

RESUMO

Articular cartilage is refractory to self-healing due to the absence of vascular, nervous, and lymphatic systems, and its repair remains a clinical challenge. Tissue regeneration through in situ recruitment of stem cells via cell-free scaffolds is a promising alternative strategy. Herein, a kind of functional injectable hydrogel system (Col-Apt@KGN MPs), which is a collagen-based and microsphere-embedded cell-free scaffold, was designed to achieve spatiotemporal regulation of endogenous mesenchymal stem cells (MSCs) recruitment and their chondrogenic differentiation by respective release of aptamer 19S (Apt19S) and kartogenin (KGN). In vitro results confirmed that the Col-Apt@KGN MPs hydrogel had sequential release characteristics. Apt19S was rapidly released from the hydrogel within 6 days, while KGN was slowly released for 33 days via the degradation of poly(lactic-co-glycolic acid) (PLGA) microspheres. When cultured with MSCs, the Col-Apt@KGN MPs hydrogel supported the adhesion, proliferation, and chondrogenic differentiation of MSCs. In vivo results indicated that the Col-Apt@KGN MPs hydrogel effectively promoted the recruitment of endogenous MSCs in a rabbit full-thickness cartilage defect model; furthermore, the Col-Apt@KGN MPs hydrogel enhanced the secretion of cartilage specific extracellular matrix and achieved the reconstruction of subchondral bone. This study demonstrates that the Col-Apt@KGN MPs hydrogel possesses great potential in recruitment of endogenous stem cells and cartilage tissue regeneration.


Assuntos
Doenças das Cartilagens , Cartilagem Articular , Células-Tronco Mesenquimais , Animais , Coelhos , Hidrogéis/metabolismo , Diferenciação Celular
15.
Angew Chem Int Ed Engl ; 62(24): e202303176, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37060295

RESUMO

Possessed with advantageous optoelectronic properties, perovskites have boosted the rapid development of solution-processed solar cells. The performance of perovskite solar cells (PSCs) is significantly weakened by the carrier loss at grain boundary grooves (GBGs); however, it receives limited attention and there lacks effective approach to solve this issue. Herein, for the first time, we constructed the tungstate/perovskite heterointerface via a "two step" in situ reaction approach that provides effective defect passivation and ensures efficient carrier dynamics at the GBGs. The exposed perovskite at grain boundaries is converted to wide-band-gap PbWO4 via an in-situ reaction between Pb2+ and tungstate ions, which passivate defects due to the strong ionic bonding. Moreover, recombination loss is further suppressed via the heterointerface energetics modification based on an additional transformation from PbWO4 to CaWO4 . PSCs based on this groove modification strategy showed good universality in both normal and inverted structure, with an improved efficiency of 23.25 % in the n-i-p device and 23.33 % in the p-i-n device. Stable power output of the modified device could maintain 91.7 % after around 1100 h, and the device efficiency could retain 92.5 % after aging in air for around 2110 h, and 93.1 % after aging at 85 °C in N2 for 972 h.

16.
J Chem Inf Model ; 63(9): 2742-2747, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37094567

RESUMO

This study demonstrates the determination of reaction pathways by evaluating the carbon kinetic isotopic effect and interpreting isotopic fractionations based on quantum chemical calculations. The reaction under investigation is methane thermogenesis from the decomposition of kerogen, which is a geochemical reaction under temperatures below 150 °C and lasts for tens of millions of years. Investigating its mechanism requires theoretical simulations because lab experiments at practical time-lengths require elevated temperatures, which introduce unwanted side reactions. Density functional theory and kinetic simulations were conducted on isotopic fractionations with the use of two possible pathways (free-radical versus carbonium), and the results were compared to field data sets. Different molecular sizes of kerogen were investigated to account for the hindrance of translation and rotation in modeling a reactant in the solid phase. Both pathways have low reaction barriers, implying that the reaction rates are limited by the concentration of active species (hydrated protons and free radicals). The results support the carbonium pathway and rule out the free-radical pathway as the 13CH4 from the latter would be 30‰ more depleted than the observed data. Additionally, simulations were conducted on hydrocarbon isotope fractionation of the carbonium pathway with consideration of hydrogen exchange between methane and water, successively reproducing the observed abundances of deuterium-containing isotopologues (13CH3D, 13CH3D, and 12CH2D2).


Assuntos
Metano , Temperatura , Cinética , Isomerismo , Metano/química , Isótopos de Carbono
17.
Small Methods ; 7(4): e2201663, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36852613

RESUMO

Fast reaction between organic salt and lead iodide always leads to small perovskite crystallites and concentrated defects. Here, polyacrylic acid is blended with organic salt, so as to regulate the crystallization in a two-step growth method. It is observed that addition of polyacrylic acid retards aggregation and crystallization behavior of the organic salt, and slows down the reaction rate between organic salt and PbI2 , by which "slow-release effect" is defined. Such effect improves crystallization of perovskite. X-ray diffraction study shows that, after addition of 2 mm polyacrylic acid, average crystallite size of perovskite increases from ≈40 to ≈90 nm, meanwhile, grain size increases. Thermal admittance spectroscopy study shows that trap density is reduced by nearly one order (especially for deep energy levels). Due to the improved crystallization and reduced trap density, charge recombination is obviously reduced, while lifetime of charge carriers in perovskite film and devices are prolonged, according to time-resolved photoluminescence and transient photo-voltage decay curve tests, respectively. Accordingly, power conversion efficiency of the device is promoted from 19.96 (±0.41)% to 21.84 (±0.25)% (with a champion efficiency of 22.31%), and further elevated to 24.19% after surface modification by octylammonium iodide.

18.
Mitochondrial DNA B Resour ; 8(1): 76-80, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643813

RESUMO

Striped large-eye bream, Gnathodentex aureolineatus (Lacepède, 1802), is of high economic value and has important ecological functions in coral reefs. However, the genetic information of this species is quite limited, and there is taxonomical difficulty in the family Lethrinidae. Here, we present the complete mitochondrial genome of G. aureolineatus obtained with a long PCR approach and Sanger sequencing. The mitogenome was 16,940 bp in length, consisting of 37 genes (13 protein-coding genes, two ribosomal RNA genes, and 22 transfer RNA genes) and two non-coding regions. Both maximum-likelihood and Bayesian inference phylogenetic trees placed the genus Gnathodentex sister to Monotaxis within Lethrinidae. These results contribute toward the taxonomy, conservation, and phylogeny of Lethrinidae.

19.
Nanoscale ; 15(5): 2305-2315, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36636960

RESUMO

Atomically dispersed metal clusters are considered as promising nanocatalysts due to their excellent physicochemical properties. Here, we report a novel strategy for precisely designing Fex (x = 1-2) cluster nanocatalysts (Fe1-N-C and Fe2-N-C) with dual catalytic activity, which can catalyze H2O2 into reactive oxygen species (ROS) and oxidize glutathione (GSH) into glutathione disulfide simultaneously. The adsorption energies of Fe-N sites in Fe2-N-C for GSH and H2O2 intermediates were well controlled due to the orbital modulation of adjacent Fe sites, contributing to the higher dual catalytic activity compared to Fe1-N-C. Additionally, tamoxifen (TAM) was loaded into Fe2-N-C (Fe2@TDF NEs) to down-regulate the intracellular pH for higher Fenton-like catalytic efficiency and ROS production. The generated ROS could induce apoptosis and lipid peroxidation, triggering ferroptosis. Meanwhile, upregulation of ROS and lipid peroxidation, along with GSH depletion and GPX4 downregulation could promote the apoptosis and ferroptosis of tumor cells. In addition, the lactic acid accumulation effect of TAM and the high photothermal conversion ability of Fe2@TDF NEs could further enhance the catalytic activity to achieve synergistic antitumor effects. As a result, this work highlights the critical role of adjacent metal sites at the atomic-level and provides a rational guidance for the design and application of nanocatalytic antitumor systems.


Assuntos
Hipertermia Induzida , Neoplasias , Humanos , Apoptose , Linhagem Celular Tumoral , Glutationa , Peróxido de Hidrogênio/química , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fototerapia , Espécies Reativas de Oxigênio/farmacologia , Ferro/química , Catálise , Nanoestruturas
20.
Acta Biomater ; 154: 194-211, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36309191

RESUMO

The suitable seeding cells and scaffolds are very important for tissue engineering to create functional cartilage. Although the physicochemical properties of scaffold and co-culture system of mesenchymal stem cells (MSCs) and chondrocytes could affect functional properties of engineered cartilage tissues respectively, the combined effects of them on chondrogenesis is currently unknown. Herein, methacrylated collagen (CMA30 and CMA80) hydrogels with different degradation rate and stiffness were prepared. The MSCs and chondrocytes were co-cultured or monocultured in collagen, CMA30 and CMA80 hydrogels in vitro or in vivo. The results demonstrated that cell spreading and proliferation was regulated by degradation rate and stiffness of hydrogels. Compared to single MSCs culture, co-culture cells in all collagen-based hydrogels significantly improved chondrogenesis. CMA30 hydrogel with moderate degradation rate and low storage modulus was the most effective for co-culture system to promote chondrogenesis compared to Col and CMA80 hydrogel in vitro culture, while there was no obvious difference between CMA30 and CMA80 hydrogel in vivo. Furthermore, the intercellular substance exchange was very important for co-culture system to maintain the positive effect on chondrogenesis. Overall, the current study highlights the synergistic effects of the physicochemical properties of collagen-based hydrogel and co-culture system on cartilage formation. STATEMENT OF SIGNIFICANCE: Scaffolds and cells play a key role in cartilage tissue engineering. The combined effects of physicochemical properties of collagen hydrogels and co-culture system (MSCs and chondrocytes) on chondrogenesis is unknown. In contrast to the studies that investigated the effect of single factor (scaffolds or cells) on cartilage formation, this manuscript explored the synergistic regulation of both scaffold properties and biological factors on chondrogenesis, and provided a promising strategy for cartilage tissue engineering.


Assuntos
Condrogênese , Hidrogéis , Hidrogéis/química , Técnicas de Cocultura , Condrócitos , Colágeno/farmacologia , Colágeno/metabolismo , Engenharia Tecidual/métodos , Diferenciação Celular , Alicerces Teciduais , Células Cultivadas
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