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1.
Crit Care Med ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780398

RESUMO

OBJECTIVES: Following current cardiopulmonary resuscitation (CPR) guidelines, which recommend chest compressions at "the center of the chest," ~50% of patients experiencing out-of-hospital cardiac arrest (OHCA) undergo aortic valve (AV) compression, obstructing blood flow. We used resuscitative transesophageal echocardiography (TEE) to elucidate the impact of uncompressed vs. compressed AV on outcomes of adult patients experiencing OHCA. DESIGN: Prospective observational cohort study. SETTING: Single center. PATIENTS: This study included adult OHCA patients undergoing resuscitative TEE in the emergency department. Patients were categorized into AV uncompressed or AV compressed groups based on TEE findings. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was sustained return of spontaneous circulation (ROSC). The secondary outcomes included end-tidal co2 (Etco2) during CPR, any ROSC, survival to ICU and hospital discharge, post-resuscitation withdrawal, and favorable neurologic outcomes at discharge. Additional analyses on intra-arrest arterial blood pressure (ABP) were also conducted. The sample size was pre-estimated at 37 patients/group. From October 2020 to January 2023, 76 patients were enrolled, 39 and 37 in the AV uncompressed and AV compressed groups, respectively. Intergroup baseline characteristics were similar. Compared with the AV compressed group, the AV uncompressed group had a higher probability of sustained ROSC (53.8% vs. 24.3%; adjusted odds ratio [aOR], 4.72; p = 0.010), any ROSC (56.4% vs. 32.4%; aOR, 3.30; p = 0.033), and survival to ICU (33.3% vs. 8.1%; aOR, 6.74; p = 0.010), and recorded higher initial diastolic ABP (33.4 vs. 11.5 mm Hg; p = 0.002) and a larger proportion achieving diastolic ABP greater than 20 mm Hg during CPR (93.8% vs. 33.3%; p < 0.001). The Etco2, post-resuscitation withdrawal, and survival to discharge revealed no significant intergroup differences. No patients were discharged with favorable neurologic outcomes. Uncompressed AV seemed critical for sustained ROSC across all subgroups. CONCLUSIONS: Absence of AV compression during OHCA resuscitation is associated with an increased chance of ROSC and survival to ICU. However, its effect on long-term outcomes remains unclear.

2.
Transplant Proc ; 56(3): 554-556, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38670734

RESUMO

INTRODUCTION: Urothelial cancers were one of the most common malignancies in patients with kidney transplants. Although radical nephroureterectomy is still the standard of care in current guidelines, studies have shown that significantly improved perioperative outcomes can be achieved for patients who underwent bilateral nephroureterectomy. Our study provides evidence on the outcome of bilateral nephroureterectomy and unilateral nephroureterectomy in kidney recipients with upper tract urothelial carcinoma. MATERIAL AND METHODS: In the study, the data of patients from a single center, Chang Gung Memorial Hospital Linkou branch, were collected retrospectively from 1981 to 2023. The patient's detailed information was collected through the medical records in the hospital. RESULTS: A total of 44 cases of kidney recipients with upper urinary tract urothelial carcinoma were collected in this study. Of the patients, 19 nephroureterectomies were performed before 2008 and 24 afterward. Incidental findings of contralateral tumors were noted in 3 out of 6 patients who underwent bilateral nephroureterectomy before 2008 and 3 out of 12 after 2008. Contralateral upper urinary tract urothelial carcinoma after unilateral nephroureterectomy was noted in 3 patients within a median of 8.1 years. The progression-free survival of bilateral nephroureterectomy was significantly better compared with a unilateral group (not reached, 15.8 years, respectively). DISCUSSION: Our study, along with previous studies, provides evidence that bilateral nephroureterectomy may be a better treatment option in kidney recipients with upper tract urothelial carcinoma. Our study has several limitations based on its retrospective nature.


Assuntos
Transplante de Rim , Nefroureterectomia , Humanos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias Urológicas/cirurgia , Adulto , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Carcinoma de Células de Transição/cirurgia , Resultado do Tratamento , Neoplasias Ureterais/cirurgia , Nefrectomia
3.
Materials (Basel) ; 17(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38541392

RESUMO

Perovskite thin films directly impact solar cell properties, making defect reduction crucial in perovskite solar cell research. In our study, we used perovskite quantum dots in the anti-solvent to act as nucleation centers in MAPbI3 thin films. These centers had lower nucleation barriers than homogeneous nucleation, improving perovskite crystallinity, reducing defects, and extending carrier lifetime. Fine-tuning the energy band also enhanced carrier transport. The most effective results were obtained using CsPb(Br0.5 I0.5)3 perovskite quantum dots. The resulting device, ITO/SnO2/MAPbI3 (300 nm)/spiro-OMeTAD (200 nm)/Ag (100 nm), achieved a 12.88% power conversion efficiency, a 16% increase from the standard element. The modified device maintained approximately 95% of its efficiency over 100 h in a 70% humidity environment.

4.
Transplant Proc ; 56(3): 546-549, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38523012

RESUMO

PURPOSE: We observed transient elevations in creatinine levels among kidney recipients after three traditional holidays in Taiwan. This retrospective cohort study aimed to compare the changes in eGFR levels after Chinese New Year, Dragon Boat Festival, and Mid-Autumn Festival, all of which are associated with high-calorie and high-fat diets. MATERIALS AND METHODS: We conducted a retrospective analysis of 364 kidney recipients with stable graft function who were following at Chang Gung Memorial Hospital Linkou from 2018 to 2020. The graft function before and after the festival was determined by calculating the eGFR level using the serum creatinine measured during clinic visits prior to and following the festival. The patients were then categorized into subgroups based on their sex, BMI, and co-morbidities. The eGFR levels before and after the festival were evaluated and compared within these subgroups. RESULTS: A total of 301 kidney recipients have been finally included in this retrospective cohort study. The analysis showed a significant decrease in overall eGFR levels after Chinese New Year (from 56.92 ± 29.70 to 55.14 ± 24.79, P = .006), Mid-Autumn Festival (from 54.03 ± 24.61 to 53.35 ± 24.33, P = .008), and Dragon Boat Festival only in 2020 (from 50.98 ± 24.35 to 49.99 ± 23.45, P = .018). The analysis of subgroups suggested a tendency of renal function decline after all 3 traditional holidays in patient groups with DM or hypertension or nonoverweight status. CONCLUSION: In this study, we observed a significant decline in renal function among kidney recipients following traditional holidays in Taiwan, particularly among recipients with hypertension or diabetes mellitus or those who were not overweight.


Assuntos
Taxa de Filtração Glomerular , Férias e Feriados , Transplante de Rim , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Taiwan , Creatinina/sangue , Rim/fisiopatologia
6.
Trials ; 25(1): 118, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347550

RESUMO

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is a significant public health issue worldwide and is associated with low survival rates and poor neurological outcomes. The generation of optimal coronary perfusion pressure (CPP) via high-quality chest compressions is a key factor in enhancing survival rates. However, it is often challenging to provide adequate CPP in real-world cardiopulmonary resuscitation (CPR) scenarios. Based on animal studies and human trials on improving CPP in patients with nontraumatic OHCA, resuscitative endovascular balloon occlusion of the aorta (REBOA) is a promising technique in these cases. This study aims to investigate the benefits of REBOA adjunct to CPR compared with conventional CPR for the clinical management of nontraumatic OHCA. METHODS: This is a parallel-group, randomized, controlled, multinational trial that will be conducted at two urban academic tertiary hospitals in Korea and Taiwan. Patients aged 20-80 years presenting with witnessed OHCA will be enrolled in this study. Eligible participants must fulfill the inclusion criteria, and written informed consent should be collected from their legal representatives. Patients will be randomly assigned to the intervention (REBOA-CPR) or control (conventional CPR) group. The intervention group will receive REBOA and standard advanced cardiovascular life support (ACLS). Meanwhile, the control group will receive ACLS based on the 2020 American Heart Association guidelines. The primary outcome is the return of spontaneous circulation (ROSC). The secondary outcomes include sustained ROSC, survival to admission, survival to discharge, neurological outcome, and hemodynamic changes. DISCUSSION: Our upcoming trial can provide essential evidence regarding the efficacy of REBOA, a mechanical method for enhancing CPP, in OHCA resuscitation. Our study aims to determine whether REBOA can improve treatment strategies for patients with nontraumatic OHCA based on clinical outcomes, thereby potentially providing valuable insights and guiding further advancements in this critical public health area. TRIAL REGISTRATION: ClinicalTrials.gov NCT06031623. Registered on September 9, 2023.


Assuntos
Oclusão com Balão , Reanimação Cardiopulmonar , Procedimentos Endovasculares , Parada Cardíaca Extra-Hospitalar , Animais , Humanos , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Reanimação Cardiopulmonar/efeitos adversos , Reanimação Cardiopulmonar/métodos , Ressuscitação/métodos , Aorta , Hemodinâmica , Oclusão com Balão/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos
7.
Transplant Proc ; 56(3): 550-553, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395658

RESUMO

BACKGROUND: New-onset diabetes after transplantation and increased insulin resistance have both been shown to affect graft performance and survival after kidney transplantation. Thus, we aimed to evaluate the predictive roles of different insulin resistance indices on early graft function in kidney transplant recipients. MATERIALS AND METHODS: We conducted a retrospective analysis of non-diabetic patients who received kidney transplantation between January 1, 2018 and December 31, 2021. The primary outcome was the predictive role of different insulin resistance indices on early graft function of serum creatinine level and estimated glomerular filtration rate at 1, 3, 6, and 12 months. The secondary outcome analyzed was the possible clinical predictive factors for poor kidney graft function at 12 months. RESULTS: Among 123 kidney transplantation patients, stratification with homeostatic model assessment for insulin resistance showed no significant difference in kidney graft function outcome at 1, 3, 6, and 12 months. However, patients with a higher insulin-to-glucose ratio exhibited a significantly higher serum creatinine level at 3 and 6 months and a significantly lower estimated glomerular filtration rate level at 3, 6, and 12 months. Using multivariate logistic regression analysis, patients with a higher insulin-to-glucose ratio were associated with a poorer kidney graft function 12 months after transplantation. CONCLUSION: Patients with a higher baseline insulin resistance with an insulin-to-glucose ratio ≥of 0.092 exhibited a significantly worse early kidney graft function. Thus, with the identification of patients with increased insulin resistance, early intervention, and preventive measures can be implemented to enhance graft performance further.


Assuntos
Taxa de Filtração Glomerular , Sobrevivência de Enxerto , Resistência à Insulina , Transplante de Rim , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Adulto , Creatinina/sangue , Glicemia/metabolismo , Glicemia/análise , Resultado do Tratamento , Insulina/sangue , Fatores de Risco
8.
J Formos Med Assoc ; 123(1): 23-35, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37573159

RESUMO

BACKGROUND/PURPOSE: To develop a prediction model for emergency medical technicians (EMTs) to identify trauma patients at high risk of deterioration to emergency medical service (EMS)-witnessed traumatic cardiac arrest (TCA) on the scene or en route. METHODS: We developed a prediction model using the classical cross-validation method from the Pan-Asia Trauma Outcomes Study (PATOS) database from 1 January 2015 to 31 December 2020. Eligible patients aged ≥18 years were transported to the hospital by the EMS. The primary outcome (EMS-witnessed TCA) was defined based on changes in vital signs measured on the scene or en route. We included variables that were immediately measurable as potential predictors when EMTs arrived. An integer point value system was built using multivariable logistic regression. The area under the receiver operating characteristic (AUROC) curve and Hosmer-Lemeshow (HL) test were used to examine discrimination and calibration in the derivation and validation cohorts. RESULTS: In total, 74,844 patients were eligible for database review. The model comprised five prehospital predictors: age <40 years, systolic blood pressure <100 mmHg, respiration rate >20/minute, pulse oximetry <94%, and levels of consciousness to pain or unresponsiveness. The AUROC in the derivation and validation cohorts was 0.767 and 0.782, respectively. The HL test revealed good calibration of the model (p = 0.906). CONCLUSION: We established a prediction model using variables from the PATOS database and measured them immediately after EMS personnel arrived to predict EMS-witnessed TCA. The model allows prehospital medical personnel to focus on high-risk patients and promptly administer optimal treatment.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Auxiliares de Emergência , Parada Cardíaca Extra-Hospitalar , Humanos , Adolescente , Adulto , Parada Cardíaca Extra-Hospitalar/terapia , Hospitais , Estudos de Coortes
10.
PeerJ ; 11: e16262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38025730

RESUMO

Background: With higher age, frailty escalates the risk of falls, unexpected physical dysfunction, hospitalization, and mortality. Polypharmacy in the older population is a major challenge that not only increases medical costs, but also may worsen the risk of hospitalization and death. More importantly, the properties of anti-cholinergic drugs contribute various negative effects. This study aimed to investigate the sex difference in the association of polypharmacy, anticholinergic burden, and frailty with mortality. Methods: Participants older than 65 years who attended the geriatric outpatient clinic of the study center between January 2015 and July 2020 were invited to participate in this retrospective study. Comprehensive geriatric assessment data were collected and the phenotype of frailty was determined by Fried's criteria. Cox regression and the Kaplan-Meier curve were used to identify risk factors of 5-year survival along with intergroup differences in the risks. Results: Of the 2,077 participants, 47.5% were female. The prevalence of frailty and the rate of polypharmacy were 44.7% and 60.6%, respectively. Higher age, male sex, low body mass index, low Mini-Mental State Examination scores, low activities of daily living, frailty status, polypharmacy, and a high Charlson Comorbidity Index score, and greater anticholinergic burden were significant risk factors that were associated with the 5-year all-cause mortality. Male patients with frailty exhibited the highest risks of mortality compared with male patients without frailty and female patients with or without frailty. Polypharmacy was significantly associated with a higher 5-year mortality rate in the frail male group compared with the non-frail male. In frail female group, individuals with a higher anticholinergic burden (as indicated by the Anticholinergic Cognitive Burden Scale) from drug usage exhibited an elevated 5-year mortality rate. Conclusions: Polypharmacy and greater anticholinergic burden, synergistically interacted with frailty and intensified the 5-year mortality risk in a gender-specific manner. To mitigate mortality risks, clinicians should prudently identify polypharmacy and anticholinergic burden in the older population.


Assuntos
Fragilidade , Humanos , Masculino , Feminino , Idoso , Fragilidade/diagnóstico , Idoso Fragilizado , Atividades Cotidianas , Estudos Retrospectivos , Polimedicação , Antagonistas Colinérgicos/efeitos adversos
11.
Langmuir ; 39(41): 14638-14651, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37782834

RESUMO

In harsh environments, it is crucial to design personal protective materials that possess both puncture/cut resistance and chemical resistance. In order to fulfill these requirements, this study introduces an innovative approach that combines hydrophobically modified rigid nanoparticles with thermoplastic polyurethane elastomers. These materials are then laminated with high-performance aramid fabrics through a scraping process, resulting in a multifunctional composite with puncture/cut resistance, superhydrophobicity, self-cleaning properties, and acid/alkali resistance. The quasi-static puncture tests conducted reveal the remarkable performance of the composite. The maximum spike puncture resistance reaches 267.62 N, which is 17.14 times higher than that of the pure fabric (15.61 N). Similarly, the maximum knife puncture resistance reaches 115.02 N, exhibiting a 5.01 times increase compared to that of the pure aramid fabric (22.97 N). Furthermore, the results obtained from the yarn pull-out, fabric burst strength, and tearing experiments demonstrate that the incorporation of rigid nanoparticles significantly enhances the friction between the yarns, enabling a greater number of yarns to participate in the dissipation of impact energy. As a result, the puncture resistance of the fabric is greatly improved. Significantly, the composite exhibits sustained superhydrophobicity even after exposure to harsh chemicals such as concentrated sulfuric acid and sodium hydroxide as well as undergoing cyclic mechanical wear. These findings highlight the composite's exceptional durability and resistance to corrosion. Overall, this study offers insights and methods for the development of multifunctional flexible puncture-resistant equipment for individuals.

12.
Materials (Basel) ; 16(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834601

RESUMO

This study presents gallium-doped zinc oxide (ZnO:Ga, GZO) thin films. GZO thin films with both high transparency and low sheet resistance were prepared by RF sputtering and then post-annealed under nitrogen and hydrogen forming gas. With post-annealing at 450 °C, the proposed films with a film thickness of 100 nm showed high transparency (94%), while the sheet resistance of the films was reduced to 29 Ω/square, which was comparable with the performances of commercial indium tin oxide (ITO) samples. Post-annealing under nitrogen and hydrogen forming gas enhanced the films' conductivity while altering the thin-film composition and crystallinity. Nitrogen gas played a role in improving the crystallinity while maintaining the oxygen vacancy of the proposed films, whereas hydrogen did not dope into the thin film, thus maintaining its transparency. Furthermore, hydrogen lowered the resistance of GZO thin films during the annealing process. Then, the detailed mechanisms were discussed. Hydrogen post-annealing helped in the removal of oxygen, therefore increasing the Ga3+ content, which provided extra electrons to lower the resistivity of the films. After the preferable nitrogen/hydrogen forming gas treatment, our proposed films maintained high transparency and low sheet resistance, thus being highly useful for further opto-electronic applications.

13.
Proc Natl Acad Sci U S A ; 120(39): e2305078120, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37695879

RESUMO

Current un-sustainable plastic management is exacerbating plastic pollution, an urgent shift is thus needed to create a recycling society. Such recovering carbon (C) and hydrogen (H) from waste plastic has been considered as one practical route to achieve a circular economy. Here, we performed a simple pyrolysis-catalysis deconstruction of waste plastic via a monolithic multilayer stainless-steel mesh catalyst to produce multiwalled carbon nanotubes (MWCNTs) and H2, which are important carbon material and energy carrier to achieve sustainable development. Results revealed that the C and H recovery efficiencies were as high as 86% and 70%, respectively. The unique oxidation-reduction process and improvement of surface roughness led to efficient exposure of active sites, which increased MWCNTs by suppressing macromolecule hydrocarbons. The C recovery efficiency declined by only 5% after 10 cycles, proving the long-term employment of the catalyst. This catalyst can efficiently convert aromatics to MWCNTs by the vapor-solid-solid mechanism and demonstrate good universality in processing different kinds of waste plastics. The produced MWCNTs showed potential in applications of lithium-ion batteries and telecommunication. Owing to the economic profits and environmental benefits of the developed route, we highlighted its potential as a promising alternative to conventional incineration, simultaneously achieving the waste-to-resource strategy and circular economy.

14.
ACS Appl Mater Interfaces ; 15(34): 41151-41161, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37596967

RESUMO

In recent years, the demand for detection and diagnostic methods has consistently risen due to the aging of the population and the increase in the number of patients with chronic diseases. Label-free biomedical detection techniques have emerged as indispensable instruments for diagnosing a variety of diseases. The development of label-free and highly sensitive near-infrared (NIR) biomedical detection technology has attracted considerable attention. As a label-free, swift, and cost-effective analytical technique, it has demonstrated immense potential for a wide range of applications. We successfully assembled FAPbI3 near-infrared perovskite quantum dots (NIPQDs) into SiO2 shells using a rapid room-temperature atmospheric synthesis method, obtaining monodisperse FAPbI3@SiO2 nanocomposites (NCs) with a high photoluminescence quantum yield (PLQY) of 72%. Additionally, the incorporation of hydrophobic multi-branched trioctylphosphine oxide effectively passivated the surface defects of FAPbI3 NIPQDs and suppressed the hydrolysis rate of tetraethoxysilane, enabling the formation of a highly stable and high PLQY nanoscale-particle level within the FAPbI3@SiO2 core-shell structure. Notably, we successfully incorporated FAPbI3@SiO2 core-shell NCs onto InGaN blue chip as NIR excitation light sources for surface plasmon resonance sensing platforms, providing a novel platform for bioanalytical detection. With a detection sensitivity of 6302.5 nm/RIU, the system demonstrated high sensitivity, stability, and dependability. This achievement expands the biomedical research field's capacity for diagnosis, monitoring, and treatment.

15.
BMC Health Serv Res ; 23(1): 878, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37605162

RESUMO

BACKGROUND: The Coronavirus disease 2019 (COVID-19) pandemic has placed a great burden on Taiwan's health care system. It has also had a great impact on other public health issues, including cancer screening. Delayed cancer screening was also noticed in the U.S. during the pandemic, which may have led to both delayed diagnosis and poor prognosis. In Taiwan, population-based cancer screening for breast cancer, oral cancer, colon cancer and cervical cancer has been executed and ongoing for years. METHOD: In this study we have analyzed the change in screening numbers for cancer during the period of the 2019 to 2021 COVID-19 outbreak in Taiwan. RESULTS: Through our results we found that total cancer screening numbers decreased from 307,547 to 103,289 (a 66% decrease) from the years 2020 to 2021. Specifically, a 63%, 79%, 65% and 71% decrease in screening cases was seen for colon cancer, oral cancer, cervical cancer and breast cancer, respectively, during that period. A similar condition was noticed when comparing 2019 to 2021 when the disclosed total cancer screening numbers decreased by 70% (2019-2021); 65%, 83%, 70% and 76% in colon cancer, oral cancer, cervical cancer and breast cancer, respectively. Among these various cancer screenings, oral cancer screening showed the greatest reduction rate (a drop of 83% compared to 2019 and 79% compared to 2020). We also compared the reduction rates taken from different regions in Taiwan. It was in Taipei, where most COVID-19 cases were noted, that the greatest reduction rate of cancer screening numbers occurred (a drop of76% compared to 2019 and 74% compared to 2020). A proportional decrease of screening cases was also noticed in all areas when confirmed COVID-19 cases rose. CONCLUSIONS: Screening for cancers dropped significantly due to the pandemic and its effect on long-term health needs to be evaluated. Additionally, efforts should be taken to address these cancer screening number deficits which have taken place during the COVID-19 pandemic.


Assuntos
Neoplasias da Mama , COVID-19 , Neoplasias do Colo , Neoplasias Bucais , Neoplasias do Colo do Útero , Humanos , Feminino , Detecção Precoce de Câncer , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/epidemiologia , Pandemias/prevenção & controle , Taiwan/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia
16.
ChemSusChem ; 16(19): e202300886, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37498683

RESUMO

Solar-driven high-value utilization of biomass and its derivatives has attracted tremendous attention in replacing fossil sources to generate chemicals. Developing high-performance photocatalysts to selectively catalyze bio-platform molecules remains a challenge. Herein, biomass-based 5-hydroxymethylfurfural (HMF) was efficiently and selectively photooxidized to 2, 5-diformylfuran (DFF) using a metal-free polyimide (PI). PI with moderate photooxidation capacity delivered high DFF selectivity of 91 % and high apparent quantum efficiency of 1.13 %, nearly 7 times higher than that of graphitic carbon nitride. Experimental measurements and theoretical calculations revealed that the band structure and photooxidation capability of PI can be continuously modulated by varying the molar ratio of amine and anhydride. Mechanism analysis depicted that holes and superoxide radicals play crucial roles in the efficient photooxidation of HMF to DFF. This work provides guidance on designing efficient polymeric photocatalysts for oxidating biomass and its derivatives to value-added chemicals.

17.
Waste Manag ; 168: 54-62, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37276634

RESUMO

After the peak of rapid wind power development, a large amount of wind turbine blades reach/exceed their service life due to aging or damage. These ex-service wind turbine blades (EWTB) will increase the issue of its high-efficient utilization in the future decades. Among several treatment methods, pyrolysis has been considered as a promising solution to separate inorganic fiberglass and make organic epoxy resin (OER) high-value-added converted. However, the pyrolysis mechanism, chemical composition, and fiberglass separation of EWTB have not been deeply studied. In this paper, the synthetic model compound of epoxy resin was firstly used to investigate the thermal weight loss and pyrolysis kinetics, the thermal weight loss temperature range of which was 300 âˆ¼ 480 °C. The apparent activation energy was minimum when the conversion rate was 0.6, and the pyrolysis mechanism was determined by the Coats-Redfern method as a diffusion control. On this basis, a lab-scale fixed-bed was conducted to study fast-heating pyrolysis characteristics of EWTB. It could be analyzed that the chemicals in the pyrolytic liquid were a series of phenolics with methyl and vinyl substituted benzene rings (e.g., bisphenol A, p-isopropenyl phenol, and phenol). Bisphenol A presented a relatively high selectivity of 51.02%, which could be recycled as the main raw material for the synthesis of epoxy resins. Furthermore, clean fiberglass could be separated by combusting the residual carbon in pyrolytic solids. These results might be useful for achieving the separation and resource utilization of organic and inorganic components of EWTB.


Assuntos
Resinas Epóxi , Pirólise , Cinética , Fenóis
18.
Nanomaterials (Basel) ; 13(12)2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37368281

RESUMO

Recently, resistive random access memory (RRAM) has been an outstanding candidate among various emerging nonvolatile memories for high-density storage and in-memory computing applications. However, traditional RRAM, which accommodates two states depending on applied voltage, cannot meet the high density requirement in the era of big data. Many research groups have demonstrated that RRAM possesses the potential for multi-level cells, which would overcome demands related to mass storage. Among numerous semiconductor materials, gallium oxide (a fourth-generation semiconductor material) is applied in the fields of optoelectronics, high-power resistive switching devices, and so on, due to its excellent transparent material properties and wide bandgap. In this study, we successfully demonstrate that Al/graphene oxide (GO)/Ga2O3/ITO RRAM has the potential to achieve two-bit storage. Compared to its single-layer counterpart, the bilayer structure has excellent electrical properties and stable reliability. The endurance characteristics could be enhanced above 100 switching cycles with an ON/OFF ratio of over 103. Moreover, the filament models are also described in this thesis to clarify the transport mechanisms.

20.
Transplant Proc ; 55(4): 727-732, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37183066

RESUMO

PURPOSE: Intraoperative hemodynamic instability was proven to be associated with delayed graft function (DGF) after kidney transplantation. This retrospective study aims to find the specific intraoperative hemodynamic parameters as an efficient predicting factor of DGF. MATERIALS AND METHODS: Patients who underwent kidney transplantation between 2020 and 2022 were enrolled and classified into DGF and non-DGF groups. Pediatric and multiorgan recipients were excluded. Hemodynamic parameters such as central venous pressure, mean arterial pressure, cardiac output, and cardiac index (CI) at the timings of wound incision, graft reperfusion, and operation completion were recorded, respectively. A comparison of parameters between these 2 groups was analyzed. RESULTS: We enrolled 42 recipients, with 26 in the DGF group and 16 in the non-DGF group. Compared with the DGF group, CI around graft reperfusion was significantly higher in the non-DGF group (3.97 vs 4.67 L/min/m2, P = .043). Other hemodynamic variables revealed no statistical difference. In the results of multivariate analysis, the deceased donor source, the greater volume of blood loss, and the lower CI around graft reperfusion were considered independent risk factors for DGF. Using CI around graft reperfusion to conduct a receiver operating characteristic (ROC) curve for DGF prediction, the area under the ROC curve achieved a value of 0.739 (95% confidence interval, 0.579-0.900), with the optimal cut-point value at CI = 4.245 L/min/m2. CONCLUSION: The cardiac index value around graft reperfusion was statistically associated with the incidence of DGF and might be used as a valid predicting factor.


Assuntos
Transplante de Rim , Humanos , Criança , Transplante de Rim/efeitos adversos , Função Retardada do Enxerto/epidemiologia , Estudos Retrospectivos , Hemodinâmica , Fatores de Risco , Sobrevivência de Enxerto , Doadores de Tecidos
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