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1.
Ultrason Sonochem ; 109: 107027, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39146819

RESUMO

Nickel/iron-layered double hydroxide (NiFe-LDH) tends to undergo an electrochemically induced surface reconstruction during the water oxidation in alkaline, which will consume excess electric energy to overcome the reconstruction thermodynamic barrier. In the present work, a novel ultrasonic wave-assisted Fenton reaction strategy is employed to synthesize the surface reconstructed NiFe-LDH nanosheets cultivated directly on Ni foam (NiFe-LDH/NF-W). Morphological and structural characterizations reveal that the low-spin states of Ni2+ (t2g6eg2) and Fe2+ (t2g4eg2) on the NiFe-LDH surface partially transform into high-spin states of Ni3+ (t2g6eg1) and Fe3+ (t2g3eg2) and formation of the highly active species of NiFeOOH. A lower surface reconstruction thermodynamic barrier advantages the electrochemical process and enables the NiFe-LDH/NF-W electrode to exhibit superior electrocatalytic water oxidation activity, which delivers 10 mA cm-2 merely needing an overpotential of 235 mV. Besides, surface reconstruction endows NiFe-LDH/NF-W with outstanding electrooxidation activities for organic molecules of methanol, ethanol, glycerol, ethylene glycol, glucose, and urea. Ultrasonic-assisted Fenton reaction inducing surface reconstruction strategy will further advance the utilization of NiFe-LDH catalyst in water and organics electrooxidation.

2.
Adv Healthc Mater ; : e2401954, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39039985

RESUMO

The bis-(diethyldithiocarbamate)-copper (CuET), the disulfiram (DSF)-Cu complex, has exhibited noteworthy anti-tumor property. However, its efficacy is compromised due to the inadequate oxidative conditions and the limitation of bioavailable copper. Because CuET can inactivate valosin-containing protein (VCP), a bioinformatic pan-cancer analysis of VCP is first conducted in this study to identify CuET as a promising anticancer drug for diverse cancer types. Then, based on the drug action mechanism, a nanocomposite of CuET and copper oxide (CuO) is designed and fabricated utilizing bovine serum albumin (BSA) as the template (denoted as CuET-CuO@BSA, CCB). CCB manifests peroxidase (POD)-mimicking activity to oxidize the tumor endogenous H2O2 to generate reactive oxygen species (ROS), enhancing the chemotherapy effect of CuET. Furthermore, the cupric ions released after enzymatic reaction can regenerate CuET, which markedly perturbs intracellular protein homeostasis and induces apoptosis of tumor cells. Meanwhile, CCB triggers cuproptosis by inducing the aggregation of lipoylated proteins. The multifaceted action of CCB effectively inhibits tumor progression. Therefore, this study presents an innovative CuET therapeutic strategy that creates an oxidative microenvironment in situ and simultaneously self-supply copper source for CuET regeneration through the combination of CuO nanozyme with CuET, which holds promise for application of CuET for effective tumor therapy.

3.
Nanotechnology ; 35(37)2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38861971

RESUMO

HfO2-based ferroelectric materials as the most promising candidate for the ferroelectric memories, have been widely studied for more than a decade due to their excellent ferroelectric properties and CMOS compatibility. In order to realize its industrialization as soon as possible, researchers have been devoted to improving the reliability performance, such as wake up, imprint, limited endurance, et al. Among them, the breakdown characteristic is one of main failure mechanisms of HfO2-based ferroelectric devices, which limits the write/read reliability of the devices. Based on this, we systematically studied the effect of thickness on the time-dependent dielectric breakdown (TDDB) tolerate capability of HfO2-ZrO2(HZO) FE films under both forward and reverse electrical stress conditions. The thickness of HZO FE film ranged from 6 to 20 nm. Our findings reveal that decreasing the thickness of the HZO FE film leads to an improvement in TDDB tolerance capability which is attributed to the fact that higher density of oxygen vacancies in thinner HZO FE films can effectively inhibit the generation of new oxygen vacancies and the growth of conductive filaments, thus effectively improving the TDDB characteristics. These results provide a potential solution for mitigating breakdown characteristics of HfO2-based ferroelectric devices in memory applications.

4.
Entropy (Basel) ; 26(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920457

RESUMO

In the realm of cardiac research, the control of spiral waves and turbulent states has been a persistent focus for scholars. Among various avenues of investigation, the modulation of ion currents represents a crucial direction. It has been proved that the methods involving combined control of currents are superior to singular approaches. While previous studies have proposed some combination strategies, further reinforcement and supplementation are required, particularly in the context of controlling arrhythmias through the combined regulation of two potassium ion currents. This study employs the Luo-Rudy phase I cardiac model, modulating the maximum conductance of the time-dependent potassium current and the time-independent potassium current, to investigate the effects of this combined modulation on spiral waves and turbulent states. Numerical simulation results indicate that, compared to modulating a single current, combining reductions in the conductance of two potassium ion currents can rapidly control spiral waves and turbulent states in a short duration. This implies that employing blockers for both potassium ion currents concurrently represents a more efficient control strategy. The control outcomes of this study represent a novel and effective combination for antiarrhythmic interventions, offering potential avenues for new antiarrhythmic drug targets.

5.
Nanomaterials (Basel) ; 14(2)2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38251165

RESUMO

Perovskite/silicon tandem solar cells have garnered considerable interest due to their potential to surpass the Shockley-Queisser limit of single-junction Si solar cells. The rapidly advanced efficiencies of perovskite/silicon tandem solar cells benefit from the significant improvements in perovskite technology. Beginning with the evolution of wide bandgap perovskite cells towards two-terminal (2T) perovskite/silicon tandem solar cells, this work concentrates on component engineering, additives, and interface modification of wide bandgap perovskite cells. Furthermore, the advancements in 2T perovskite/silicon tandem solar cells are presented, and the influence of the central interconnect layer and the Si cell on the progression of the tandem solar cells is emphasized. Finally, we discuss the challenges and obstacles associated with 2T perovskite/silicon tandem solar cells, conducting a thorough analysis and providing a prospect for their future.

6.
Adv Sci (Weinh) ; 10(30): e2303911, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37698584

RESUMO

The emergence of multi-drug resistant (MDR) pathogens is a major public health concern, posing a substantial global economic burden. Photothermal therapy (PTT) at mild temperature presents a promising alternative to traditional antibiotics due to its biological safety and ability to circumvent drug resistance. However, the efficacy of mild PTT is limited by bacterial thermotolerance. Herein, a nanocomposite, BP@Mn-NC, comprising black phosphorus nanosheets and a manganese-based nanozyme (Mn-NZ) is developed, which possesses both photothermal and catalytic properties. Mn-NZ imparts glucose oxidase- and peroxidase-like properties to BP@Mn-NC, generating reactive oxygen species (ROS) that induce lipid peroxidation and malondialdehyde accumulation across the bacterial cell membrane. This process disrupts unprotected respiratory chain complexes exposed on the bacterial cell membrane, leading to a reduction in the intracellular adenosine triphosphate (ATP) content. Consequently, mild PTT mediated by BP@Mn-NC effectively eliminates MDR infections by specifically impairing bacterial thermotolerance because of the dependence of bacterial heat shock proteins (HSPs) on ATP molecules for their proper functioning. This study paves the way for the development of a novel photothermal strategy to eradicate MDR pathogens, which targets bacterial HSPs through ROS-mediated inhibition of bacterial respiratory chain activity.


Assuntos
Nanocompostos , Termotolerância , Humanos , Compostos de Manganês , Óxidos , Terapia Fototérmica , Espécies Reativas de Oxigênio , Temperatura , Trifosfato de Adenosina , Manganês , Nanocompostos/uso terapêutico
7.
ACS Appl Mater Interfaces ; 15(34): 40719-40726, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37590369

RESUMO

High-quality, stable perovskite films with a wide band gap between 1.65 and 1.80 eV are highly suitable for efficient and cost-competitive silicon-based tandem solar cells. Herein, we demonstrate that the combined strategies of the Pb(SCN)2 additive and air annealing can enable the Cs0.22FA0.78Pb(I0.85Br0.15)3 films with a wide band gap of 1.65 eV and favored properties including pure composition, high crystallinity, micro-sized grains, and reduced defects. With these desired films, the average efficiencies of semitransparent perovskite solar cells (PSCs) are boosted from (18.13 ± 0.31) to (20.35 ± 0.28)%. Further, the semitransparent PSC is used to assemble the four-terminal perovskite/TOPCon tandem solar cell. Benefiting from its excellent performance and preferred optical properties, the obtained tandem solar cell yields a milestone efficiency of 30.32%.

8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 35(7): 719-723, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37545449

RESUMO

OBJECTIVE: To analyze the clinical characteristics of patients with emergency in-hospital cardiac arrest (IHCA) in Kashgar, Xinjiang Uygur Autonomous Region and the factors affecting the success rate of cardiopulmonary resuscitation. METHODS: Retrospectively selected patients who had cardiac arrest and cardiopulmonary resuscitation in the emergency department of the People's Hospital of 6 counties and cities in Kashgar area from January 2019 to January 2022. The clinical data of all patients were collected, including gender, age, major underlying diseases, the beginning and duration of resuscitation, the number of electric defibrillation acute physiology and chronic health evaluation II (APACHE II). According to whether the resuscitation was successful, all patients were divided into successful resuscitation group and failed resuscitation group. The clinical characteristics of the two groups were compared. Then, the influencing factors of the success rate of cardiopulmonary resuscitation in IHCA patients were analyzed by binary Logistic regression. RESULTS: A total of 1 376 patients were enrolled, including 1 117 cases of failed resuscitation and 259 cases of successful resuscitation. The success rate of resuscitation was 18.82%. Compared with the resuscitation failure group, the patients in the successful resuscitation group were younger (age: 49.10±20.99 vs. 58.44±18.32), the resuscitation start time was earlier [resuscitation start time ≤ 5 minutes: 76.45% (198/259) vs. 66.61% (744/1 117)], the proportion of cardiovascular and cerebrovascular diseases was lower [cardiovascular disease: 49.42% (128/259) vs. 58.19% (650/1 117), cerebrovascular disease: 17.37% (45/259) vs. 21.58% (241/1 117)], the number of electric defibrillation was lower [times: 0 (0, 2) vs. 1 (0, 1)], the proportion of endotracheal intubation was more [80.31% (208/259) vs. 55.60% (621/1 117)], APACHE II score was lower (13.75±8.03 vs. 17.90±4.63), and the difference was statistically significant (all P < 0.01). Binary Logistic regression analysis showed that age, start time of resuscitation, ventilation mode and APACHE II score were protective factors affecting the success rate of cardiopulmonary resuscitation in patients with emergency IHCA [age: odds ratio (OR) = 0.982, 95% confidence interval (95%CI) was 0.973-0.991, P < 0.001; resuscitation start time ≤ 5 minutes: OR = 0.629, 95%CI was 0.409-0.966, P = 0.034; tracheal intubation assisted ventilation: OR = 0.243, 95%CI was 0.149-0.397, P < 0.001; low APACHE II score: OR = 0.871, 95%CI was 0.836-0.907, P < 0.001], while underlying diseases (cardiovascular diseases) are a risk factor affecting the success rate of cardiopulmonary resuscitation (OR = 1.190, 95%CI was 1.015-1.395, P = 0.036). CONCLUSIONS: Age, resuscitation start time, ventilation mode, APACHE II score and major underlying diseases (cardiovascular diseases) have a greater impact on the success rate of resuscitation in IHCA patients. The above factors are conducive to improving or formulating more effective rescue strategies for IHCA patients, so as to achieve the purpose of improving the success rate of clinical treatment.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Parada Cardíaca/terapia , Cardioversão Elétrica , Hospitais
9.
Research (Wash D C) ; 6: 0196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465160

RESUMO

Wide-bandgap (WBG) perovskite solar cells (PSCs) are essential for highly efficient and stable silicon/perovskite tandem solar cells. In this study, we adopted a synthetic strategy with lead thiocyanate (Pb(SCN)2) additive and methylammonium chloride (MACl) posttreatment to enhance the crystallinity and improve the interface of WBG perovskite films with a bandgap of 1.68 eV. The excessive PbI2 was formed at grain boundaries and converted into MAPbI3-xClx perovskites, which are utilized to form the graded heterojunction (GHJ) and compressive strain. This is beneficial for passivating nonradiative recombination defects, suppressing halide phase segregation, and facilitating carrier extraction. Subsequently, the device with GHJ delivered a champion efficiency of 20.30% and superior stability in ambient air and under 85 °C. Finally, we achieved a recorded efficiency of 30.91% for 4-terminal WBG perovskite/TOPCon tandem silicon solar cells. Our findings demonstrate a promising approach for fabricating efficient and stable WBG PSCs through the formation of GHJ.

10.
Artigo em Inglês | MEDLINE | ID: mdl-37428661

RESUMO

Incremental random weight networks (IRWNs) face the issues of weak generalization and complicated network structure. There is an important reason: the learning parameters of IRWNs are determined in a random fashion without guidance, which may increase many redundant hidden nodes, and thereby leading to inferior performance. To resolve this issue, a novel IRWN with compact constraint that guides the assignment of random learning parameters (CCIRWN) is developed in this brief. Using the iteration method of Greville, a compact constraint that simultaneously assures the quality of generated hidden nodes and the convergence of the CCIRWN is built to perform learning parameter configuration. Meanwhile, the output weights of the CCIRWN are assessed analytically. Two types of learning methods for constructing the CCIRWN are proposed. Finally, the performance evaluation of the proposed CCIRWN is undertaken on the 1-D nonlinear function approximation, several real-world datasets, and data-driven estimation based on the industrial data. Numerical and industrial examples indicate that the proposed CCIRWN with compact structure can achieve favorable generalization ability.

11.
Int J Nanomedicine ; 18: 2359-2370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37187997

RESUMO

Introduction: Large bone abnormalities are commonly treated using distraction osteogenesis (DO), but it is not suitable for a long-term application; therefore, there is an urgent need for adjuvant therapy that can accelerate bone repair. Methods: We have synthesized mesoporous silica-coated magnetic nanoparticles doped with cobalt ions (Co-MMSNs) and assessed their capacity to quicken bone regrowth in a mouse model of DO. Furthermore, local injection of the Co-MMSNs significantly accelerated bone healing in DO, as demonstrated by X-ray imaging, micro-CT, mechanical tests, histological evaluation, and immunochemical analysis. Results: In vitro, the Co-MMSNs exhibited good biocompatibility and induced angiogenic gene expression and osteogenic development in bone mesenchymal stem cells. And the Co-MMSNs can promote bone regeneration in a rat DO model. Discussion: This study demonstrated the significant potential of Co-MMSNs to shorten the DO treatment duration and effectively reduce the incidence of complications.


Assuntos
Nanopartículas de Magnetita , Osteogênese por Distração , Camundongos , Ratos , Animais , Osteogênese por Distração/métodos , Dióxido de Silício/farmacologia , Cobalto/farmacologia , Nanopartículas de Magnetita/uso terapêutico , Osteogênese , Regeneração Óssea , Diferenciação Celular
12.
Mater Today Bio ; 19: 100578, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36880082

RESUMO

The acidic microenvironment is one of the remarkable features of tumor and is also a reliable target for tumor theranostics. Ultrasmall gold nanoclusters (AuNCs) have good in vivo behaviors, such as non-retention in liver and spleen, renal clearance, and high tumor permeability, and held great potential for developing novel radiopharmaceuticals. Herein, we developed pH-sensitive ultrasmall gold nanoclusters by introducing quaternary ammonium group (TMA) or tertiary amine motifs (C6A) onto glutathione-coated AuNCs (TMA/GSH@AuNCs, C6A-GSH@AuNCs). Density functional theory simulation revealed that radiometal 89Sr, 223Ra, 44Sc, 90Y, 177Lu, 89Zr, 99mTc, 188Re, 106Rh, 64Cu, 68Ga, and 113Sn could stably dope into AuNCs. Both TMA/GSH@AuNCs and C6A-GSH@AuNCs could assemble into large clusters responding to mild acid condition, with C6A-GSH@AuNCs being more effective. To assess their performance for tumor detection and therapy, TMA/GSH@AuNCs and C6A-GSH@AuNCs were labeled with 68Ga, 64Cu, 89Zr and 89Sr, respectively. PET imaging of 4T1 tumor-bearing mice revealed TMA/GSH@AuNCs and C6A-GSH@AuNCs were mainly cleared through kidney, and C6A-GSH@AuNCs accumulated in tumors more efficiently. As a result, 89Sr-labeled C6A-GSH@AuNCs eradicated both the primary tumors and their lung metastases. Therefore, our study suggested that GSH-coated AuNCs held great promise for developing novel radiopharmaceuticals that specifically target the tumor acidic microenvironment for tumor diagnosis and treatments.

13.
ACS Appl Mater Interfaces ; 14(33): 37504-37513, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35970519

RESUMO

Dual-emitting polymer dots (dual-Pdots) in the visible and second near-infrared (NIR-II) region can facilitate the high-resolution imaging of the fine structure and improve the signal-to-noise ratio in in vivo imaging. Herein, combining high brightness of Pdots and multi-scale imaging, we synthesized dual-Pdots using a simple nano-coprecipitation method and performed multi-functional imaging of vessels, brown adipose tissue, and bones. Results showed that in vivo blood vessel imaging had a high resolution of up to 5.9 µm and bone imaging had a signal-to-noise ratio of 3.9. Moreover, dual-Pdots can accumulate in the interscapular brown adipose tissue within 2 min with a signal-to-noise ratio of 5.8. In addition, the prepared dual-Pdots can image the lymphatic valves and the frequency of contraction. Our study provides a feasible method of using Pdots as nanoprobes for multi-scale imaging in the fields of metabolic disorders, skeletal system diseases, and circulatory systems.


Assuntos
Polímeros , Pontos Quânticos , Tecido Adiposo Marrom/diagnóstico por imagem , Polímeros/química , Pontos Quânticos/química , Semicondutores , Tomografia Computadorizada por Raios X
14.
Polymers (Basel) ; 14(13)2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35808795

RESUMO

To promote the performance of perovskite solar cells (PSCs), its theoretical power conversion efficiency (PCE) and high stability, elaborative defect passivation, and interfacial engineering at the molecular level are required to regulate the optoelectric properties and charge transporting process at the perovskite/hole transport layer (HTL) interfaces. Herein, we introduce for the first time a multifunctional dipole polymer poly(2-ethyl-2-oxazoline) (PEOz) between the perovskite and Spiro-OMeTAD HTL in planar n-i-p PSCs, which advances the PSCs toward both high efficiency and excellent stability by stimulating three beneficial effects. First, the ether-oxygen unshared electron pairs in PEOz chemically react with unsaturated Pb2+ on the perovskite surfaces by forming a strong Pb-O bond, which effectively reduces the uncoordinated defects on the perovskite surfaces and enhances the absorption ability of the resulting PSCs. Second, the dipole induced by PEOz at the perovskite/HTL interface can decrease the HOMO and LUMO level of Spiro-OMeTAD and optimize the band alignment between these layers, thereby suppressing the interfacial recombination and accelerating the hole transport/extraction ability in the cell. Third, the hygroscopic PEOz thin film can protect perovskite film from water erosion by absorbing the water molecules before perovskite does. Finally, the PEOz-modified PSC exhibits an optimized PCE of 21.86%, with a high short-circuit current density (Jsc) of 24.88 mA/cm2, a fill factor (FF) of 0.79, and an open-circuit voltage (Voc) of 1.11 V. The unencapsulated devices also deliver excellent operation stability over 300 h in an ambient atmosphere with a humidity of 30~40% and more than 10 h under thermal stress.

15.
Mater Today Bio ; 15: 100317, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35757035

RESUMO

Polymer dots (Pdots) have been applied to imaging lymph nodes (LNs) and lymphatic vessels (LVs) in living mice and rats. However, the mechanism of absorption, distribution, metabolism, and excretion of Pdots in LNs and LVs is still unclear. Therefore, the relationship between Pdots and immune cells, LVs and collagen fibers in lymphatics was studied by multiple in vivo and ex vivo microscopic imaging methods and detection techniques. Flow cytometry showed that Pdots could be phagocytosed by macrophages and monocytes, and had no relationship with B cells, T cells and dendric cells in LNs. Silver staining, immunofluorescence and two-photon microscope showed that Pdots gathered in collagen fibers and LVs of LNs. Furthermore, immunofluorescence imaging results verified that Pdots were distributed in the extracellular space of collecting LVs endothelial cells. In addition, Pdots in the collecting LVs were basically cleared by leaking into the surrounding tissue or draining LNs after 21 days of injection. During the long-time observation, Pdots also helped monitor the contraction frequency and variation range of LV. Our study lays a foundation on the research of Pdots as the carrier to study lymphatic structure and function in the future.

16.
Acta Biomater ; 146: 450-464, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35526739

RESUMO

Phototherapy, particularly photothermal therapy (PTT) and photodynamic therapy (PDT), has been widely investigated for tumor treatment. However, the limited tissue penetration depth of light in the near-infrared I (NIR-I) region and the hypoxic tumor microenvironment (TME) severely constrain their clinical applications. To address these challenges, in the present study, we developed a chlorin e6 (Ce6) and MnO2-coloaded, hyaluronic acid (HA)-coated single-walled carbon nanohorns (SWNHs) nanohybrid (HA-Ce6-MnO2@SWNHs) for PDT and PTT combination therapy of tumor. HA-Ce6-MnO2@SWNHs responded to the mild acidic TME to ameliorate tumor hypoxia, thus enhancing tumor PDT. Moreover, HA-Ce6-MnO2@SWNHs had a high photothermal conversion efficiency at 1064 nm (55.48%), which enabled deep tissue penetration (3.05 cm) and allowed for highly efficient tumor PTT in near-infrared II (NIR-II) window. PDT and PTT combination therapy with HA-Ce6-MnO2@SWNHs achieved a good therapeutic efficacy on 4T1 tumor-bearing mice, eradicating the primary tumors and suppressing cancer recurrence. Our study provides a promising strategy for developing a hypoxia relief and deep tissue penetration phototherapy platform by using SWNHs for highly effective tumor PDT and NIR-II PTT combination therapy. STATEMENT OF SIGNIFICANCE: The hypoxic tumor microenvironment (TME) and the limited penetration of the NIR-I light in biological tissues compromise the efficacy of photothermal therapy (PTT) and photodynamic therapy (PDT) on tumors. Here, we developed a chlorin e6 (Ce6) and MnO2-coloaded, hyaluronic acid (HA)-coated single-walled carbon nanohorns (SWNHs) nanohybrid (HA-Ce6-MnO2@SWNHs) for PDT and PTT combination therapy of tumors. The nanohybrid could efficiently accumulate in tumors through CD44-mediated active targeting. The sequential MnO2-enhanced PDT and efficient NIR-II PTT had a remarkable therapeutic effect by eliminating the primary tumor and simultaneously inhibiting tumor recurrence.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Carbono , Linhagem Celular Tumoral , Ácido Hialurônico/farmacologia , Hipóxia/terapia , Compostos de Manganês/farmacologia , Camundongos , Neoplasias/tratamento farmacológico , Óxidos/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Terapia Fototérmica , Microambiente Tumoral
17.
Clin Lab ; 68(4)2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35443599

RESUMO

BACKGROUND: The aim of the study was to investigate the correlation between serum magnesium (Mg) level and cardiac valve calcification (CVC) in patients with chronic kidney disease (CKD). METHODS: A total of 232 CKD patients hospitalized from August 2016 to December 2020 were divided into CVC and non-CVC groups. Their clinical data and laboratory examination results were compared, the risk factors for CVC in CKD patients were explored using logistic regression analysis, and Spearman's method was used to analyze the correlation between serum Mg level and CVC degree. According to the tertiles of mean serum Mg level, they were assigned into low serum Mg group (≤ 0.96 mmol/L), middle serum Mg group (0.97 - 1.07 mmol/L), and high serum Mg group (≥ 1.08 mmol/L). The relationship of serum Mg level with CVC risk in CKD patients was analyzed through the Cox regression model, and a prediction model was established using independent risk factors. RESULTS: Long CKD duration, low serum Mg level, high serum phosphorus (P) level, and high CKD stage were independent risk factors for CVC. Serum Mg level was significantly negatively correlated with the severity of CVC (r = -0.743, p < 0.05). The risk of CVC was significantly higher in low serum Mg group than that in high serum Mg group [hazard ratio (HR) = 2.852, 95% confidence interval (CI): 1.325 - 6.432, p = 0.005]. A CVC prediction model was established based on independent risk factors as follows: CVC predictive value = EXP [0.491 - 0.546 (CKD duration) - 0.454 (serum P level) + 2.145 (serum Mg level) - 0.812 (CKD stage)]/1 + EXP [0.491 - 0.546 (CKD duration) - 0.454 (serum P level) + 2.145 (serum Mg level) - 0.812 (CKD stage)]. The area under curve of the model was 0.750 (95% CI: 0.822 - 0.965), and that of the CVC prediction model for CKD patients in test set was 0.774 (95% CI: 0.761 - 0.975), showing no significant difference from that in training set (p > 0.05). CONCLUSIONS: Low serum Mg level serves as an independent risk factor for CVC in CKD patients, and may increase the risk of CVC. Therefore, the serum Mg level in CKD patients should be corrected timely in clinical practice.


Assuntos
Calcinose , Doenças das Valvas Cardíacas , Insuficiência Renal Crônica , Calcinose/diagnóstico , Calcinose/etiologia , Feminino , Doenças das Valvas Cardíacas/complicações , Valvas Cardíacas , Humanos , Magnésio , Masculino , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/diagnóstico , Fatores de Risco
18.
Polymers (Basel) ; 14(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35054749

RESUMO

Perovskite solar cells (PSCs) based on the 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) hole transport layer have exhibited leading device performance. However, the instability caused by this organic function layer is a very important limiting factor to the further development of PSCs. In this work, the spiro-OMeTAD is doped with polymethyl methacrylate (PMMA), which is further used as the hole transport layer to improve the device stability. It is shown that the PMMA can effectively improve the moisture and oxygen resistance of spiro-OMeTAD, which leads to improved device stability by separating the perovskite layer from moisture and oxygen. The device efficiency can maintain 77% of the original value for PSCs with the PMMA-doped spiro-OMeTAD hole transport layer, under a natural air environment (RH = 40%) for more than 80 days. The results show that the moisture- and oxygen-resistant PMMA:spiro-OMeTAD hole transport layer is effective at improving the device performance.

19.
Nanomaterials (Basel) ; 13(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36615982

RESUMO

In this paper, the method for growing α-Ga2O3 films on c-plane sapphire substrates using an inexpensive fine-channel mist-CVD face-to-face heating plate was investigated. Because high temperatures can result in reactor deformation, expensive AlN ceramics resistant to deformation are used as the reactor fabrication material in traditional fine-channel mist-CVD equipment, which limits its use for promotion and research purposes. In this work, we used a face-to-face heating method to replace the traditional single-sided heating method which will reduce the requirement for equipment sealability. Therefore, cheap quartz can be used to replace expensive AlN ceramics to make reactors, which can greatly reduce the cost of mist-CVD equipment. We also investigated the effects of substrate temperature and carrier gas on the crystalline quality and surface morphology of α-Ga2O3 films. By optimizing the fabrication conditions, we obtained triangular grains with edges that were clearly visible in atomic force microscopy images. Using absorption spectrum analysis, we also found that the optical bandgap of the film reached 5.24 eV. Finally, we recorded a value of 508 arcsec for the full width at half maximum of the α-Ga2O3 (0006) diffraction peak in the X-ray diffraction pattern.

20.
Nanomaterials (Basel) ; 11(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34835848

RESUMO

As one of the important technologies in the field of heterogeneous integration, transfer technology has broad application prospects and unique technical advantages. This transfer technology includes the wet chemical etching of a sacrificial layer, such that silicon nano-film devices are released from the donor substrate and can be transferred. However, in the process of wet etching the SiO2 sacrificial layer present underneath the single-crystal silicon nano-film by using the transfer technology, the etching is often incomplete, which seriously affects the efficiency and quality of the transfer and makes the device preparation impossible. This article analyzes the principle of incomplete etching, and compares the four factors that affect the etching process, including the size of Si nano-film on top of the sacrificial layer, the location of the anchor point, the shape of Si nano-film on top of the sacrificial layer, and the thickness of the sacrificial layer. Finally, the etching conditions are obtained to avoid the phenomenon of incomplete etching of the sacrificial layer, so that the transfer technology can be better applied in the field of heterogeneous integration. Additionally, Si MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) on sapphire substrate were fabricated by using the optimized transfer technology.

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