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1.
ACS Omega ; 9(23): 24633-24642, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38882097

RESUMO

SrFe1-x Si x O3-δF y cathode materials (x = 0.05, 0.1, 0.15; y = 0, 0.1, 0.5) were prepared via a solid-state method. X-ray diffraction results show that the synthesized F doping samples were perovskite structure. X-ray photoelectron spectroscopy findings show that F- anions were doped into SrFe1-x Si x O3-δ. Transmission electron microscopy and energy-dispersive spectroscopy were performed to analyze the microstructure and element distribution in the materials, respectively. Double-layer composite cathode symmetric cells were prepared through a screen printing method. Scanning electron microscopy images revealed that the double-layer composite cathode adhered well to the electrolyte. The doping with F- can increase the coefficient of thermal expansion of SrFe1-x Si x O3-δ. The electrochemical impedance spectroscopy results indicate that the oxygen transport capacity of the SrFe0.95Si0.05O3-δ material can be improved by doping with F-, but such a method can decrease the oxygen transport capacity of SrFe0.9Si0.1O3-δ. At 800 °C, the peak power density of the single cell supported by an anode and SrFe0.9Si0.1O3-δF0.1 as the cathode reached 388.91 mW/cm2. Thus, the incorporation of F- into SrFe1-x Si x O3-δ cathode materials can improve their electrochemical performance and enable their application as cathode materials for solid-oxide fuel cells.

2.
RSC Adv ; 14(28): 19707-19717, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38903670

RESUMO

In recent decades, environmental protection and energy issues have gained significant attention, and the development of efficient, environmentally friendly catalysts has become especially crucial for the advancement of photocatalytic technology. This study employs the sintering method to produce biochar. A hybrid photocatalyst for the degradation of RHB under visible light was prepared by loading varying proportions of biochar onto g-C3N4 using ultrasonic technology. Among them, 2% CGCD (2% biochar/g-C3N4) achieved a degradation rate of 91.3% for RHB after 30 minutes of visible light exposure, which was more than 25% higher than GCD (g-C3N4), and exhibited a higher photocurrent intensity and lower impedance value. The enhancement in photocatalytic activity is primarily attributed to the increased utilization efficiency of visible light and the electron transfer channel effect from a minor amount of biochar, effectively reducing the recombination of photo-generated charge carriers on the g-C3N4 surface, thereby significantly improving photocatalytic activity. The degradation of RHB is synergistically mediated by O2 -, h+ (photo-generated holes), and ˙OH. The free radical capture experiment indicates that O2 - and ˙OH are the primary active components, followed by h+.

3.
RSC Adv ; 14(25): 17498-17506, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38818363

RESUMO

Nowadays, the widespread concern over controlling CO2 emissions and mitigating the adverse effects of greenhouse gases on global climate has attracted significant attention. In this study, g-C3N4 was synthesized by thermopolymerizing urea. Subsequently, ZIF-8 was combined with g-C3N4 using an in situ deposition method, resulting in the fabrication of ZIF-8/g-C3N4 composite photocatalysts at various molar ratios. Effective incorporation of ZIF-8 into g-C3N4 suppressed the recombination of photogenerated electrons and holes, thereby enhancing CO2 capture capacity and preserving light absorption capabilities. The ZIF-8/g-C3N4 composite demonstrates excellent photocatalytic performance for CO2 reduction, where the optimized material exhibited a CO2 adsorption capacity 1.52 times that of pure g-C3N4 and increased the conversion of CO2 to CH4 by more than sevenfold. This study harnesses the superior CO2 adsorption properties of metal-organic frameworks to develop more efficient photocatalysts, enhancing CO2 conversion efficacy and offering insights for developing efficient photocatalysts that utilize CO2.

4.
Sci Rep ; 14(1): 9760, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684847

RESUMO

Metallurgical dust and sludge are solid waste resources with recycling value. In recent years, rotary hearth furnace has become the most important means to treat metallurgical dust and sludge because of its wide range of raw materials and strong treatment capacity. In this study blast furnace ash and converter sludge were selected as the research objects, and high-quality metallized pellets were prepared based on the rotary hearth furnace process. The strength changed of pellets, the reduction process of iron oxides and the removal process of zinc during the roasting of pellets in rotary hearth furnace were studied. To explore the reasonable roasting condition for preparing metallized pellets in rotary hearth furnace. The optimum roasting temperature of the pellets was 1250℃ and the roasting time was 25 min. The compressive strength, metallization rate and dezincification rate of metallized pellets reached 1361N, 97.44% and 95.67%, respectively. The efficient resource utilization of various metallurgical dust and sludge is realized.

5.
BMC Public Health ; 23(1): 2506, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097979

RESUMO

BACKGROUND: Many researchers have examined the impact of social insurance on health in elderly. However, in most cases, they have only demonstrated correlational results and have not been able to determine causal effects, possibly because confounding biases have not been fully addressed. In this study, we investigated the health effects of the New Rural Pension Scheme (NRPS) on the elderly (age≥60 years old) with chronic diseases in rural areas, and to explore the causal relationship and effects of NRPS and health status. METHODS: This paper used data from the 2018 China Health and Retirement Longitudinal Study (CHARLS) and applied Bayesian networks and fuzzy regression discontinuity design to conduct causal analysis. Bayesian networks were used to explore the causal directed acyclic graphs of factors related to NRPS and health status. Based on the results of Bayesian network, a fuzzy regression discontinuity design was employed to estimate the causal effect of NRPS on health status. RESULTS: Among rural elderly with chronic diseases, Bayesian network mapping of causal relationships among NRPS, health status and covariates showed that age was a common cause of NRPS receipt and satisfaction with health. The results of the fuzzy regression discontinuity analysis showed that the effect of receiving NRPS on the health status was positive, but there was no statistically significant difference concerning the interval estimates. The results of the subgroup analysis with chronic obstructive pulmonary disease (COPD) and asthma indicated that the effect of NRPS receipt on the health status of elderly people with COPD was positive. There was a statistically significant effect of receiving NRPS on self-rated health description ([Formula: see text]) and health satisfaction ([Formula: see text]) in COPD population and a statistically significant effect of receiving NRPS on health satisfaction in asthma population ([Formula: see text]). CONCLUSION: This paper has confirmed the contribution and positive causal effect of NRPS on health status in a subgroup of older adults with COPD and asthma, using the CHARLS database as evidence. Thus, Chinese government should increase the take-up rate of the NRPS to enhance their positive impact on health status of elderly people with chronic diseases in rural areas.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Idoso , Pessoa de Meia-Idade , Aposentadoria , Estudos Longitudinais , Teorema de Bayes , Pensões , Nível de Saúde , População Rural , Doença Crônica , China/epidemiologia , Asma/epidemiologia
6.
RSC Adv ; 13(44): 30606-30614, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37859775

RESUMO

This study aims to investigate the implications of transition-metal Zn doping at the B-site on the crystal structure, average thermal expansion coefficient (TEC), electrocatalytic activity, and electrochemical performance of LaBaFe2O5+δ by preparing LaBaFe2-xZnxO5+δ (x = 0, 0.05, 0.1, 0.15, 0.2, LBFZx). The X-ray diffraction (XRD) results show that Zn2+ doping does not change the crystal structure, the unit cell volume increases, and the lattice expands. The X-ray photoelectron spectroscopy (XPS) and mineral titration results show that the oxygen vacancy concentration and Fe4+ content gradually increase with the increase in doping amount. TEC decreases with the increase in Zn2+ doping amount, and the TEC of LBFZ0.2 is 11.4 × 10-6 K-1 at 30-750 °C. The conductivity has the best value of 103 S cm-1 at the doping amount of x = 0.1. The scanning electron microscopy (SEM) images demonstrate that the electrolyte CGO(Gd0.1Ce0.9O1.95) becomes denser after high-temperature calcination, and the cathode material is well attached to the electrolyte. The electrochemical impedance analysis shows that Zn2+ doping at the B-site can reduce the (Rp) polarization resistance, and the Rp value of the symmetric cell with LaBaFe1.8Zn0.2O5+δ as cathode at 800 °C is 0.014 Ω cm2. The peak power density (PPD) value of the anode-supported single cell is 453 mW cm-2, which shows excellent electrochemical performance.

7.
Materials (Basel) ; 16(16)2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37629888

RESUMO

The morphologies and sizes of TiN inclusions in gear steel 20CrMnTi have a significant impact on its service performance. This paper selects rare earth Ce to modify TiN inclusions in 20CrMnTi. The inclusions are analyzed by SEM (scanning electron microscope), EBSD (electron back-scattered diffraction), EDS (energy disperse spectroscopy), and OTS statistical software, and Thermo-Calc software is used to calculate the inclusion formations. The inclusions of MgAlO4-Ce and CeAlO3 can be formed when rare earth Ce is added into 20CrMnTi, which becomes TiN nucleation core after precipitation. Without the addition of rare earth Ce, square TiN inclusions ranging from 2 to 5 µm account for 60% of the total inclusions in 20CrMnTi. After adding rare earth Ce, the TiN inclusions in 20CrMnTiCe account for 36.7% of the total inclusions. Due to the new phase formations of MgAlO4-TiN and CeAlO3-TiN with sizes less than 2 µm, the titanium-containing inclusions are refined. Fatigue tests are conducted on the steels before and after the addition of Ce. The average fatigue lives of 20CrMnTi do not reach 107 times, and the deviations between the maximum and minimum fatigue lives are great. Large-sized TiN are the main inclusions that affect the fatigue performance of 20CrMnTi. The average fatigue lives of 20CrMnTiCe exceed 107 times, and the deviations of the fatigue lives are smaller than those of 20CrMnTi.

8.
J Cardiovasc Pharmacol Ther ; 28: 10742484231185985, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415421

RESUMO

BACKGROUND AND AIMS: Esmolol is a common short-acting drug to control ventricular rate. This study aimed to evaluate the association between use of esmolol and mortality in critically ill patients. METHODS: This is a retrospective cohort study from MIMIC-IV database containing adult patients with a heart rate of over 100 beats/min during the intensive care unit (ICU) stay. Multivariable Cox proportional hazard models and logistic regression were used to explore the association between esmolol and mortality and adjust confounders. A 1:1 nearest neighbor propensity score matching (PSM) was performed to minimize potential cofounding bias. The comparison for secondary outcomes was performed at different points of time using an independent t-test. RESULTS: A total of 30,332 patients were reviewed and identified as critically ill. There was no significant difference in 28-day mortality between two groups before (HR = 0.90, 95% CI = 0.73-1.12, p = 0.343) and after PSM (HR = 0.84, 95% CI = 0.65-1.08, p = 0.167). Similar results were shown in 90-day mortality before (HR = 0.93, 95% CI = 0.75-1.14, p = 0.484) and after PSM (HR = 0.85, 95% CI = 0.67-1.09, p = 0.193). However, esmolol treatment was associated with higher requirement of vasopressor use before (HR = 2.89, 95% CI = 2.18-3.82, p < 0.001) and after PSM (HR = 2.66, 95% CI = 2.06-3.45, p < 0.001). Esmolol treatment statistically reduced diastolic blood pressure (DBP), mean arterial pressure (MAP), and heart rate (all p < 0.001) and increased fluid balance at 24 hours (p < 0.05) but did not significantly lower SBP (p = 0.721). Patients in esmolol group showed no significant difference in lactate levels and daily urine output when compared with those in non-esmolol group when adjusted for confounders (all p > 0.05). CONCLUSION: Esmolol treatment was associated with reduced heart rate and lowered DBP and MAP, which may increase vasopressor use and fluid balance at the timepoint of 24 hours in critically ill patients during ICU stay. However, after adjusting for confounders, esmolol treatment was not associated with 28-day and 90-day mortality.


Assuntos
Estado Terminal , Vasoconstritores , Adulto , Humanos , Estudos Retrospectivos , Frequência Cardíaca , Vasoconstritores/farmacologia , Unidades de Terapia Intensiva
9.
RSC Adv ; 13(23): 15624-15633, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37228672

RESUMO

Nd0.6Sr0.4Co1-xCuxO3-δ (x = 0, 0.05, 0.1, 0.15, 0.2) (NSCCx) was prepared by replacing Co with Cu. Its chemical compatibility, electrical conductivity, and electrochemical properties were studied by X-ray powder diffractometry, scanning electron microscopy, and X-ray photoelectron spectroscopy. The conductivity, AC impedance spectra, and output power of the single cell were tested in an electrochemical workstation. Results showed that the thermal expansion coefficient (TEC) and electrical conductivity of the sample decreased with the increase in Cu content. The TEC of NSCC0.1 decreased by 16.28% in the temperature range of 35 °C-800 °C, and its conductivity was 541 S cm-1 at 800 °C. Furthermore, a single cell was constructed with NSCCx as the cathode, NiO-GDC as the anode, and GDC as the electrolyte. The peak power of the cell at 800 °C was 444.87 mW·cm-2, which was similar to that of the undoped sample. Compared with the undoped NSCC, NSCC0.1 showed lower TEC while maintaining its output power. Therefore, this material can be used as a cathode for solid oxide fuel cells.

10.
ACS Appl Mater Interfaces ; 15(22): 26627-26636, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37220156

RESUMO

Lithium-rich layered oxides (LRLOs), with the chemical formula of xLi2MnO3·(1 - x)LiMO2, delivering higher specific discharge capacity, are potential cathode materials for lithium-ion batteries. However, the dissolution of transition metal ions and the instability of the cathode-electrolyte interphase (CEI) hinder the commercial application of LRLOs. Herein, a simple and affordable method is developed for the construction of a robust CEI layer by quenching a kind of cobalt-free LRLO, Li1.2Ni0.15Fe0.1Mn0.55O2 (denoted as NFM), in 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether solvent. This robust CEI, with well-distributed LiF, TMFx, and partial organic component CFx, performs as a physical barrier to prevent NFM from direct contact with the electrolyte, suppresses the oxygen release, and ensures the CEI layer stability. The customized CEI with LiF and TMFx-rich phase considerably enhances the NFM cycle stability and the initial coulomb efficiency and inhibits voltage fading. This work provides a valuable strategy for designing stable interface chemistry on the cathode of lithium-ion batteries.

11.
BMC Med ; 21(1): 192, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-37226271

RESUMO

BACKGROUND: Both low-carbohydrate (LC) and calorie-restricted (CR) diets have been shown to have metabolic benefits. However, the two regimens have yet to be thoroughly compared. We conducted a 12-week randomized trial to compare the effects of these diets separately and in combination on both weight loss and metabolic risk factors in overweight/obese individuals. METHODS: A total of 302 participants were randomized to LC diet (n = 76), CR diet (n = 75), LC + CR diet (n = 76), or normal control (NC) diet (n = 75) using a computer-based random number generator. The primary outcome was the change in body mass index (BMI). The secondary outcomes included body weight, waist circumference, waist-to-hip ratio, body fat, and metabolic risk factors. All participants attended health education sessions during the trial. RESULTS: A total of 298 participants were analyzed. BMI change over 12 weeks was - 0.6 (95% CI, - 0.8 to - 0.3) kg/m2 in NC, - 1.3 (95% CI, - 1.5 to - 1.1) kg/m2 in CR, - 2.3 (95% CI, - 2.6 to - 2.1) kg/m2 in LC, and - 2.9 (95% CI, - 3.2 to - 2.6) kg/m2 in LC + CR. LC + CR diet was more effective than LC or CR diet alone at reducing BMI (P = 0.001 and P < 0.001, respectively). Furthermore, compared with the CR diet, the LC + CR diet and LC diet further reduced body weight, waist circumference, and body fat. Serum triglycerides were significantly reduced in the LC + CR diet group compared with the LC or CR diet alone. Plasma glucose, homeostasis model assessment of insulin resistance, and cholesterol concentrations (total, LDL, and HDL) did not change significantly between the groups during the 12-week intervention. CONCLUSIONS: The reduction of carbohydrate intake without restricting caloric intake is more potent to achieve weight loss over 12 weeks when compared to a calorie-restricted diet in overweight/obese adults. The combination of restricting carbohydrate and total calorie intake may augment the beneficial effects of reducing BMI, body weight, and metabolic risk factors among overweight/obese individuals. TRIAL REGISTRATION: The study was approved by the institutional review board of Zhujiang Hospital of Southern Medical University and registered at the China Clinical Trial Registration Center (registration number: ChiCTR1800015156).


Assuntos
Carboidratos da Dieta , Sobrepeso , Adulto , Humanos , Restrição Calórica , Obesidade , Dieta com Restrição de Carboidratos
12.
CMAJ ; 195(21): E729-E738, 2023 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-37247880

RESUMO

BACKGROUND: The role of statin therapy in the development of kidney disease in patients with type 2 diabetes mellitus (DM) remains uncertain. We aimed to determine the relationships between statin initiation and kidney outcomes in patients with type 2 DM. METHODS: Through a new-user design, we conducted a multicentre retrospective cohort study using the China Renal Data System database (which includes inpatient and outpatient data from 19 urban academic centres across China). We included patients with type 2 DM who were aged 40 years or older and admitted to hospital between Jan. 1, 2000, and May 26, 2021, and excluded those with pre-existing chronic kidney disease and those who were already on statins or without follow-up at an affiliated outpatient clinic within 90 days after discharge. The primary exposure was initiation of a statin. The primary outcome was the development of diabetic kidney disease (DKD), defined as a composite of the occurrence of kidney dysfunction (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m2 and > 25% decline from baseline) and proteinuria (a urinary albumin-to-creatinine ratio ≥ 30 mg/g and > 50% increase from baseline), sustained for at least 90 days; secondary outcomes included development of kidney function decline (a sustained > 40% decline in eGFR). We used Cox proportional hazards regression to evaluate the relationships between statin initiation and kidney outcomes, as well as to conduct subgroup analyses according to patient characteristics, presence or absence of dyslipidemia, and pattern of dyslipidemia. For statin initiators, we explored the association between different levels of lipid control and outcomes. We conducted analyses using propensity overlap weighting to balance the participant characteristics. RESULTS: Among 7272 statin initiators and 12 586 noninitiators in the weighted cohort, statin initiation was associated with lower risks of incident DKD (hazard ratio [HR] 0.72, 95% confidence interval [CI] 0.62-0.83) and kidney function decline (HR 0.60, 95% CI 0.44-0.81). We obtained similar results to the primary analyses for participants with differing patterns of dyslipidemia, those prescribed different statins, and after stratification according to participant characteristics. Among statin initiators, those with intensive control of high-density lipoprotein cholesterol (LDL-C) (< 1.8 mmol/L) had a lower risk of incident DKD (HR 0.51, 95% CI 0.32-0.81) than those with inadequate lipid control (LDL-C ≥ 3.4 mmol/L). INTERPRETATION: For patients with type 2 DM admitted to and followed up in academic centres, statin initiation was associated with a lower risk of kidney disease development, particularly in those with intensive control of LDL-C. These findings suggest that statin initiation may be an effective and reasonable approach for preventing kidney disease in patients with type 2 DM.


Assuntos
Diabetes Mellitus Tipo 2 , Dislipidemias , Inibidores de Hidroximetilglutaril-CoA Redutases , Insuficiência Renal Crônica , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , LDL-Colesterol , Estudos Retrospectivos , Insuficiência Renal Crônica/epidemiologia , Dislipidemias/tratamento farmacológico , Dislipidemias/epidemiologia
13.
ACS Omega ; 8(8): 8011-8018, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36873032

RESUMO

To improve the performance of the Ce0.8Gd0.2O2-δ (GDC) electrolyte in a solid oxide fuel cell, it is necessary to block the electronic conduction due to Ce3+/Ce4+ transitions occurring at elevated temperatures. In this work, a GDC/ScSZ double layer consisting of 50 nm GDC and 100 nm Zr0.8Sc0.2O2-δ (ScSZ) thin films were deposited on a dense GDC substrate by the pulsed laser deposition (PLD) technology. The effectiveness of the double barrier layer in blocking the electronic conduction of the GDC electrolyte was investigated. The results showed that the ionic conductivity of GDC/ScSZ-GDC was slightly lower than that of GDC in the temperature range of 550-750 °C, but the difference gradually decreased with the increase in temperature. At 750 °C, the conductivity of GDC/ScSZ-GDC was 1.54 × 10-2 S·cm-1, which was almost the same as that of GDC. The electronic conductivity of GDC/ScSZ-GDC was 1.28 × 10-4 S·cm-1, which was lower than that of GDC. The conductivity results showed that the ScSZ barrier layer can reduce electron transfer effectively. More obviously, the open-circuit voltage and the peak power density of the (NiO-GDC)|GDC/ScSZ-GDC|(LSCF-GDC) cell were higher than those of the (NiO-GDC)|GDC|(LSCF-GDC) cell in the temperature range of 550-750 °C. The superior performance of the GDC/ScSZ-GDC electrolyte is attributed to the ScSZ thin layer, which is effective in blocking the electronic conduction of the GDC electrolyte.

14.
Front Med (Lausanne) ; 10: 1107251, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36923011

RESUMO

Background: Previous studies have shown that dexmedetomidine (DEX) may be associated with reduced vasopressor requirements in septic shock patients, however, long-term DEX-only sedation in reducing vasopressor requirements is still controversial. Methods: A retrospective study was conducted among patients with septic shock on mechanical ventilation using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary outcome was the ratio of norepinephrine equivalent dose to mean arterial pressure (NEq/MAP) in the first 72 h after DEX or other sedatives for sedation. The secondary outcomes were key organ function parameters, 28-day mortality, and 90-day mortality. Univariate, propensity score matching (PSM), and generalized linear mixed model (GLMM) analyses were performed. Results: DEX was associated with decreased NEq/MAP in the first 72 h (difference = 0.05, 95% CI = -0.02-0.08, p = 0.002) after adjusting for confounders in the GLMM analysis. The DEX group was also associated with a lower heart rate, cardiac output (CO), lactate level, aspartate transaminase (AST) level, and higher PaO2/FiO2 ratio (p < 0.0125). Moreover, DEX only sedation was associated with reduced 90-day mortality (OR = 0.60, 95% CI = 0.37-0.94, p = 0.030). Conclusion: DEX may be associated with decreased vasopressor requirements, improved AST and PaO2/FiO2 levels, and reduced 90-day mortality in patients with septic shock, which warrants further study.

15.
ACS Omega ; 8(6): 5545-5552, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36816642

RESUMO

Ln2-x Y x CuO4+δ (Ln = Pr, Nd, Sm; x = 0, 0.025, 0.05, 0.1) cathode materials were synthesized using a sol-gel method and calcination at 1000 °C for 24 h. The phase structure, coefficient of thermal expansion (CTE), electrical conductivity, and electrochemical impedance of cathode materials were characterized. X-ray diffraction (XRD) patterns show that the cell volume of each cathode material decreases with the increase in the Y3+ doping amount and has good chemical compatibility with the Sm0.2Ce0.8O1.9 electrolyte. The thermal expansion test shows that the increase in Y3+ doping reduces the average CTE of Ln2CuO4+δ. The conductivity test shows that Y3+ doping increases the conductivity of Ln2CuO4+δ, and Pr1.975Y0.025CuO4+δ has the highest conductivity of 256 S·cm-1 at 800 °C. The AC impedance test shows that Y3+ doping reduces the polarization impedance of Ln2CuO4+δ, and Pr1.9Y0.1CuO4+δ has a minimum area-specific resistance (ASR) of 0.204 Ω·cm2 at 800 °C. In conclusion, Pr1.975Y0.025CuO4+δ has the best performance and is more suitable as a cathode material for a solid oxide fuel cell (SOFC).

16.
Ann Transl Med ; 11(2): 43, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36819561

RESUMO

Background: Basic studies show that selective 5-hydroxytryptamine type 3 (5-HT3) serotonin-receptor antagonists can protect organs from inflammatory injury and have shown lung protection. Whether 5-HT3 receptor antagonists ondansetron benefits patients with mechanical ventilation is unclear in the intensive care unit (ICU). Methods: The Medical Information Mart for Intensive Care-IV (MIMIC-IV) database was reviewed to identify patients on mechanical ventilation (aged >16 years) in the ICU, which was divided into two groups according to whether ondansetron is used. Demographic characteristics, medical history data, clinical parameters, diagnosis and treatment measures were included as covariates. Ondansetron use was defined as any kind of ondansetron administration regardless of the dose before the induction of mechanical ventilation. The primary outcome was in-hospital death. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated by multivariable Cox regression. Propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were performed to further adjust for confounding factors. Kaplan-Meier (KM) curves with log-rank test were also performed. Results: A total of 18,566 patients on mechanical ventilation were included (5,735 with ondansetron use). The overall in-hospital mortality rate of patients on mechanical ventilation was 18.9% (3,512/18,566). Approximately 13.0% (746/5,735) and 21.6% (2,766/12,831) in-hospital mortality rates occurred in the ondansetron and non-ondansetron use groups, respectively. Multivariable regression indicated that ondansetron usage was associated with a 33% and 32% lower risk of in-hospital and 60-day death (HR =0.77, 95% CI: 0.70-0.85, P<0.001; HR =0.68, 95% CI: 0.62-0.75, P<0.001) in the whole sample. Multivariable regression post-PSM indicated that ondansetron usage was associated with a 38% and 31% lower risk of in-hospital and 60-day death (HR =0.62, 95% CI: 0.56-0.68, P<0.001; HR =0.69, 95% CI: 0.62-0.77, P<0.001). Log-rank test for the KM curve of ondansetron and 60-day death was statistically significant (P<0.001). The duration of ventilator use pre- and post-PSM was statistically different (P<0.001 and P=0.007) in the two groups. Conclusions: Ondansetron usage was significantly associated with a lower mortality risk of ventilated patients in the ICU. The 5-HT3 receptor antagonist use is may be new potential adjunctive therapeutic strategy for patients on mechanical ventilation in the ICU.

17.
Minerva Anestesiol ; 89(3): 166-174, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36282224

RESUMO

BACKGROUND: The association between baseline serum chloride levels and mortality in patients with severe acute kidney injury (AKI) is unknown. Our aim was to investigate the relationship between baseline blood chloride levels and 28-day mortality in patients with AKI admitted to the ICU and to detect possible effect modifiers in this population. METHODS: AKI patients with severe critical illness were extracted from the MIMIC-IV. During ICU admission, chloride levels were measured for the first time. Our primary outcome was 28-day mortality in patients with AKI after 24 hours in the ICU. Multivariable logistic regression was used to examine the association between three groups of chloride levels and 28-day mortality, and logistic regression with restricted cubic spline was applied to detect the non-linear trendy. RESULTS: A total of 24,166 patients with critically ill AKI were included in this retrospective cohort study. The total 28-day mortality rate in the ICU was 15.9%. Overall, there was a U-shaped relationship between baseline serum chloride levels and 28-day mortality (non-linear P<0.001). Accordingly, patients with low serum chloride (<96 mEq/L) had a significantly increased risk of death compared to patients with normal serum chloride (96-108 meq/L) (adjusted OR=1.94, 95% CI: 1.68-2.24, P<0.001). None of the variables, including age, gender, 24-hour fluid intake, continuous renal replacement therapy, ventilation, Atrial fibrillation, Sequential Organ Failure Assessment score, whether to measure lactate and AKI stage, significantly modified the association between lower chloride levels and 28-day mortality. CONCLUSIONS: Low serum chloride levels at baseline were associated with death at 28 days in intensive illnesses with AKI.


Assuntos
Injúria Renal Aguda , Cloretos , Humanos , Estudos Retrospectivos , Unidades de Terapia Intensiva , Injúria Renal Aguda/terapia , Hospitalização , Estado Terminal/terapia
18.
Front Pharmacol ; 13: 1007719, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36299903

RESUMO

Background: Recombinant human thrombopoietin (rhTPO) is reported to stimulate platelet production and increase peripheral platelet counts; it is primarily used to manage chemotherapy-induced thrombocytopenia and idiopathic thrombocytopenic purpura. However, the effect of rhTPO in patients with pneumonia and thrombocytopenia remains uncertain. Objective: To assess the association of rhTPO and platelet counts in ICU patients with pneumonia and thrombocytopenia. Materials and Methods: A retrospective cohort study was performed in the ICU department, Nanfang Hospital, Southern Medical University, Guangzhou, China. From January 2016 to April 2021, patients with pneumonia and thrombocytopenia were allocated to two groups-the rhTPO and no-rhTPO groups-according to whether they received rhTPO treatment or not during their ICU stay. Demographical and clinical data were collected and analyzed using statistical software; p < 0.05 was considered statistically significant. Results: Out of 327 patients, 149 were in the rhTPO group and 178 were in the no-rhTPO group. Within the first 7 days, platelet counts increased more for patients in the rhTPO group compared with those in the no-rhTPO group (99.21 ± 102.613 vs. 2.08 ± 43.877, p = 0.000). The clinical recovery rate of platelets increased within 7 days (65.8 vs. 18.5%, p = 0.000) and, after 7 days of enrollment, hemorrhagic scores decreased more apparently in the rhTPO group (2.81 ± 2.856 vs. 1.16 ± 2.123, p = 0.000). Further, bleeding events ceased in 66.7% of the patients in the rhTPO group compared with 37.3% of the patients in the no-rhTPO group (p = 0.000). Less red-blood-cells transfusions were needed in the rhTPO group (3.639 ± 4.630 vs. 5.818 ± 6.858, p = 0.009). Furthermore, through logistic regression, rhTPO administration was found to be an independent indicator that affected the platelet recovery rate within 7 days. Conclusion: This study finds that rhTPO administration is associated with increased platelet counts, alleviated bleeding, and reduced blood transfusion. For patients with pneumonia and thrombocytopenia, rhTPO may be an effective therapeutic drug; however, more RCT trails are needed to confirm our observation.

19.
Surgery ; 172(4): 1285-1290, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35953307

RESUMO

BACKGROUND: Many studies demonstrated no improved survival in patients with pulmonary artery catheter placement. However, no consistent conclusions have been drawn regarding the impact of pulmonary artery catheter in critically ill patients with heart disease. This study aimed to investigate the association of early pulmonary artery catheter use with 28-day mortality in that population. METHODS: The Multiparameter Intelligent Monitoring in Intensive Care IV (MIMIC-IV) database, a single-center critical care database, was employed to investigate this issue. This study enrolled a total of 11,887 critically ill patients with cardiac disease with or without pulmonary artery catheter insertion. The primary outcome was 28-day mortality. The multivariate regression was modeled to examine the association between pulmonary artery catheter and outcomes. Additionally, we examined the effect modification by cardiac surgeries. Propensity score matching was conducted to validate our findings. RESULTS: No improvement in 28-day mortality was observed among the pulmonary artery catheter group compared to the non-pulmonary artery catheter group (odds ratio 95% confidence interval: 1.18 [1.00-1.38], P = .049). When stratified by cardiac surgeries, the results were consistent. The patients in the pulmonary artery catheter group had fewer ventilation-free days and vasopressor-free days than those in the nonpulmonary artery catheter group after surgery stratification. In the surgical patients, pulmonary artery catheter insertion was not associated with the occurrence of acute kidney injury, and it was associated with a higher daily fluid input (mean difference 95% confidence interval: 0.13 [0.05-0.20], P = .001). In nonsurgical patients, the pulmonary artery catheter group had a higher risk of acute kidney injury occurrence (odds ratio 95% confidence interval: 1.94 [1.32-2.84], P = .001). CONCLUSION: Early pulmonary artery catheter placement is not associated with survival benefits in critically ill patients with cardiac diseases, either in surgical or nonsurgical patients.


Assuntos
Injúria Renal Aguda , Cardiopatias , Cateterismo de Swan-Ganz , Cuidados Críticos/métodos , Estado Terminal/terapia , Cardiopatias/cirurgia , Humanos
20.
Artigo em Inglês | MEDLINE | ID: mdl-35830498

RESUMO

As a device for direct conversion of chemical energy into electrical energy, the solid oxide fuel cell (SOFC) contributes positively to the sustainable development strategy. However, the commercialization of fuel cells is still impeded by severe cathode degradation caused by its limited stability at operating temperatures and being prone to Cr-poisoning from Cr-containing alloy interconnectors commonly used in these cells. This paper reports the development of a high-durability Ba-doped LSCF(La0.6Sr0.4Co0.2Fe0.8O3-δ) cathode material under realistic fuel cell operating conditions in the presence of the Cr alloy. In particular, when tested in a symmetrical cell constructed of Ba-doped LSCF, the polarization resistance of the cell remains very low at 0.06 Ω cm2 after being tested at 800 °C for 120 h exposed to Cr in 3% humidified air. In contrast, for the undoped LSCF under the same testing conditions, the polarization resistance of the cell increases ∼10 times from 0.22 Ω cm2 of the pristine cell to 2.18 Ω cm2 after Cr-exposure testing. Furthermore, when tested in an anode-supported complete cell as a cathode under typical SOFC operation conditions at 750 °C, the cell with the Ba-doped LSCF cathode displays significantly low degradation rates of 0.00056% h-1 (without Cr) and 0.00310% h-1 (with Cr); both are much lower than that of the cell using the undoped LSCF cathode (0.00124% h-1 without Cr and 0.01082% h-1 with Cr). This enhanced durability and Cr-tolerance exhibited by the Ba-doped LSCF cathode stem from its higher crystal structure stability and improved chemical resistance compared to undoped LSCF.

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