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2.
Ann Surg Oncol ; 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068325

RESUMO

BACKGROUND: Dumping syndrome occurs frequently after esophageal cancer surgery, but the reported prevalence varied across previous studies. This systematic review and meta-analysis aimed to clarify the prevalence of dumping syndrome after esophageal cancer surgery, particularly exploring the sources of heterogeneity in previous studies. METHODS: A comprehensive literature search was conducted in PubMed, MEDLINE, Web of Science, Embase, and the Cochrane Library databases, supplemented by hand-search of reference lists, through March 2023. Random-effects meta-analysis estimated the average prevalence of dumping syndrome after esophageal cancer surgery. Heterogeneity across studies was examined by the I2 statistic and Cochran's Q test. RESULTS: Among the 2949 articles retrieved from the databases, 16 articles (15 cohort studies and 1 randomized controlled trial) met the inclusion criteria. The prevalence of dumping syndrome ranged 0-74% in these studies, showing high heterogeneity (I2 = 99%, P < 0.01), with the pooled prevalence of 27% (95% confidence interval [CI] 14-39%). The pooled prevalence in the three studies using specialized questionnaires was 67% (95% CI 60-73%), with reduced heterogeneity (I2 = 43%, P = 0.17). The prevalence also varied by year of publication, study population, and length and completeness of follow-up. CONCLUSIONS: Our findings revealed that dumping syndrome is common after esophageal cancer surgery. The varying prevalence across previous studies was probably owing to differences in measurement of dumping syndrome. Using specific patient reported outcome questionnaires is recommended for future investigations on dumping syndrome after esophageal cancer surgery.

3.
Environ Sci Technol ; 58(28): 12731-12741, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38958431

RESUMO

Effective synthesis and application of single-atom catalysts on supports lacking enough defects remain a significant challenge in environmental catalysis. Herein, we present a universal defect-enrichment strategy to increase the surface defects of CeO2-based supports through H2 reduction pretreatment. The Pt catalysts supported by defective CeO2-based supports, including CeO2, CeZrOx, and CeO2/Al2O3 (CA), exhibit much higher Pt dispersion and CO oxidation activity upon reduction activation compared to their counterpart catalysts without defect enrichment. Specifically, Pt is present as embedded single atoms on the CA support with enriched surface defects (CA-HD) based on which the highly active catalyst showing embedded Pt clusters (PtC) with the bottom layer of Pt atoms substituting the Ce cations in the CeO2 surface lattice can be obtained through reduction activation. Embedded PtC can better facilitate CO adsorption and promote O2 activation at PtC-CeO2 interfaces, thereby contributing to the superior low-temperature CO oxidation activity of the Pt/CA-HD catalyst after activation.


Assuntos
Monóxido de Carbono , Oxirredução , Platina , Monóxido de Carbono/química , Platina/química , Catálise , Cério/química , Adsorção , Propriedades de Superfície
4.
ACS Appl Mater Interfaces ; 16(30): 39387-39398, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39031912

RESUMO

Low-loading Pd supported on Fe2O3 nanoparticles was synthesized. A common nanocatalyst system with previously reported synergistic enhancement of reactivity that is attributed to the electronic interactions between Pd and the Fe2O3 support. Fe2O3-selective precoalescence overcoating with ZnO atomic layer deposition (ALD), using Zn(CH2CH3)2 and H2O as precursors, dampens competitive hydrogenation reactivity at Fe2O3-based sites. The result is enhanced efficiency at the low-loading but high reactivity Pd sites. While this increases catalyst efficiency toward most aqueous redox reactions tested, it suppresses reactivity toward polyaromatic core substrates. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) show minimal electronic impacts for the ZnO overcoat on the Pd particles, implying a predominantly physical site blocking effect as the reason for the modified reactivity. This serves as a proof-of-concept of not only stabilizing supported nanocatalysts but also altering reactivity with ultrathin ALD overcoats. The results point to a facile ALD route for selective enhancement of reactivity for low-loading Pd-based supported nanocatalysts.

5.
ACS Appl Mater Interfaces ; 16(22): 29477-29487, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38773964

RESUMO

InGaN nanorods possessing larger and wavelength selective absorption by regulating In component based visible light photodetectors (PDs) as one of the key components in the field of visible light communication have received widespread attention. Currently, the weak photoelectric conversion efficiency and slow photoresponse speed of InGaN nanorod (NR) based PDs due to high surface states of InGaN NRs impede the actualization of high-responsivity and high-speed blue light PDs. Here, we have demonstrated high-performance InGaN NR/PEDOT:PSS@Ag nanowire (NW) heterojunction blue light photodetectors utilizing surface passivation and a localized surface plasmon resonance effect. The dark current is significantly reduced by passivating the InGaN NR surface states using PEDOT:PSS. The photoelectric conversion efficiency is significantly increased by increasing light absorption due to the electromagnetic field oscillation of Ag NWs. The responsivity, external quantum efficiency, detectivity, and fall/off time of the InGaN NR/PEDOT:PSS@Ag NW PDs are up to 2.9 A/W, 856%, 6.64 × 1010 Jones, and 439/725 µs, respectively, under 1 V bias and 420 nm illumination. The proposed device design presents a novel approach toward the development of low-cost, high-responsivity, high-speed blue light photodetectors for applications involving visible light communication.

6.
Radiother Oncol ; 196: 110316, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38679201

RESUMO

BACKGROUND AND PURPOSE: This phase Ib study was designed to assess the safety/tolerability and preliminary antitumor activity of neoadjuvant low-dose radiotherapy (LDRT) plus durvalumab and chemotherapy for potentially resectable stage III non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: Eligible patients received dose-escalated radiotherapy (10 Gy in 5 fractions [cohort 1], 20 Gy in 10 fractions [cohort 2], and 30 Gy in 15 fractions [cohort 3]) according to a 3 + 3 design, with concurrent durvalumab plus standard chemotherapy for two cycles. Primary objective was safety/tolerability. Secondary objectives included major pathological response (MPR), pathological complete response (pCR), event-free survival (EFS), and exploratory biomarker analysis. RESULTS: Nine patients were enrolled and completed the planned neoadjuvant therapy. No dose-limiting toxicity was recorded. Grade 3-4 treatment-related adverse events were observed in three (33.3 %) patients. Seven (77.8 %) patients successfully converted to resectable cases with R0 resection. No treatment-related surgical delay or death was reported. The MPR and pCR rates were both 33.3 % % (1/3) for cohort 1, 66.7 % (2/3) and 0.0 % for cohort 2, and 100.0 % (3/3), and 66.7 % (2/3) for cohort 3. At data cutoff, the 12 month-EFS rates were 33.3 %, 66.7 %, and 100 % for three cohorts, respectively. By biomarker analysis, TMB values were higher in either pathologically or radiologically responders than in others (all p > 0.05). CONCLUSION: Neoadjuvant LDRT plus durvalumab and chemotherapy was well-tolerated in potentially resectable stage III NSCLC. The preliminary efficacy supports this combined regimen's potential, the optimal radiotherapy dosage was determined to be 30 Gy in 15 fractions, warranting further clinical investigation.


Assuntos
Anticorpos Monoclonais , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Terapia Neoadjuvante , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Idoso , Estadiamento de Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Dosagem Radioterapêutica
7.
J Clin Oncol ; 42(18): 2126-2131, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38574304

RESUMO

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We previously reported superior symptom control of electronic patient-reported outcome (ePRO)-based symptom management after lung cancer surgery for up to 1 month postdischarge. Here, we present the long-term results (1-12 months) of this multicenter, randomized trial, where patients were assigned 1:1 to receive postoperative ePRO-based symptom management or usual care daily postsurgery, twice weekly postdischarge until 1 month, and at 3, 6, 9, and 12 months postdischarge. Long-term patient-reported outcomes were assessed with MD Anderson Symptom Inventory-Lung Cancer module. Per-protocol analyses were performed with 55 patients in the ePRO group and 57 in the usual care group. At 12 months postdischarge, the ePRO group reported significantly fewer symptom threshold events (any of the five target symptom scored ≥4; median [IQR], 0 [0-0] v 0 [0-1]; P = .040) than the usual care group. From 1 to 12 months postdischarge, the ePRO group consistently reported significantly lower composite scores for physical interference (estimate, -0.86 [95% CI, -1.32 to -0.39]) and affective interference (estimate, -0.70 [95% CI, -1.14 to -0.26]). Early intensive ePRO-based symptom management after lung cancer surgery reduced symptom burden and improved functional status for up to 1 year postdischarge, supporting its integration into standard care.


Assuntos
Neoplasias Pulmonares , Medidas de Resultados Relatados pelo Paciente , Humanos , Neoplasias Pulmonares/cirurgia , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Qualidade de Vida
8.
J Surg Case Rep ; 2024(4): rjae225, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605697

RESUMO

Mediastinal haemangiomas pose diagnostic and therapeutic challenges owing to their rarity and complex anatomy. A 36-year-old man, with a history of smoking and drinking, presented with a posterior mediastinal mass with back pain. Initial investigations suggested a lymphangioma. However, owing to persistent symptoms and complex pathology, we performed surgical intervention involving open resection of the tumour, which was closely associated with the descending aorta and extended into the right posterior mediastinum. The surgical approach was influenced by the proximity of the tumour to vital structures, necessitating an open procedure. Postoperative complications included chylothorax, managed with a fat-free diet. The final pathological diagnosis was consistent with a benign vascular tumour with a low proliferative rate. Two months post-surgery, computed tomography revealed no complications, and the patient's pain had decreased. A multidisciplinary approach and surgical intervention played important roles in the diagnosis and treatment of this posterior mediastinal haemangioma.

9.
Small ; 20(32): e2400096, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38516956

RESUMO

The extremely poor solution stability and massive carrier recombination have seriously prevented III-V semiconductor nanomaterials from efficient and stable hydrogen production. In this work, an anodic reconstruction strategy based on group III-V active semiconductors is proposed for the first time, resulting in 19-times photo-gain. What matters most is that the device after anodic reconstruction shows very superior stability under the protracted photoelectrochemical (PEC) test over 8100 s, while the final photocurrent density does not decrease but rather increases by 63.15%. Using the experiment and DFT theoretical calculation, the anodic reconstruction mechanism is elucidated: through the oxidation of indium clusters and the migration of arsenic atoms, the reconstruction formed p+-GaAs/a-InAsN. The hole concentration of the former is increased by 10 times (5.64 × 1018 cm-1 increases up to 5.95 × 1019 cm-1) and the band gap of the latter one is reduced to a semi-metallic state, greatly strengthening the driving force of PEC water splitting. This work turns waste into treasure, transferring the solution instability into better efficiency.

10.
Gastroenterology ; 167(3): 485-492.e3, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38513743

RESUMO

BACKGROUND & AIMS: Helicobacter pylori infection is associated with a decreased risk of esophageal adenocarcinoma, and the decreasing prevalence of such infection might contribute to the increasing incidence of this tumor. We examined the hypothesis that eradication treatment of H pylori increases the risk of esophageal adenocarcinoma. METHODS: This population-based multinational cohort, entitled "Nordic Helicobacter Pylori Eradication Project (NordHePEP)," included all adults (≥18 years) receiving H pylori eradication treatment from 1995-2018 in any of the 5 Nordic countries (Denmark, Finland, Iceland, Norway, and Sweden) with follow-up throughout 2019. Data came from national registers. We calculated standardized incidence ratios (SIRs) with 95% confidence intervals (CIs) by dividing the cancer incidence in the exposed cohort by that of the entire Nordic background populations of the corresponding age, sex, calendar period, and country. Analyses were stratified by factors associated with esophageal adenocarcinoma (ie, education, comorbidity, gastroesophageal reflux, and certain medications). RESULTS: Among 661,987 participants who contributed 5,495,552 person-years after eradication treatment (median follow-up, 7.8 years; range, 1-24 years), 550 cases of esophageal adenocarcinoma developed. The overall SIR of esophageal adenocarcinoma was not increased (SIR = 0.89; 95% CI, 0.82-0.97). The SIR did not increase over time after eradication treatment, but rather decreased and was 0.73 (95% CI, 0.61-0.86) at 11-24 years after treatment. There were no major differences in the stratified analyses. The overall SIR of esophageal squamous cell carcinoma, calculated for comparison, showed no association (SIR = 0.99; 95% CI, 0.89-1.11). CONCLUSIONS: This absence on an increased risk of esophageal adenocarcinoma after eradication treatment of H pylori suggests eradication is safe from a cancer perspective.


Assuntos
Adenocarcinoma , Antibacterianos , Neoplasias Esofágicas , Infecções por Helicobacter , Helicobacter pylori , Humanos , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/microbiologia , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/diagnóstico , Adenocarcinoma/epidemiologia , Adenocarcinoma/microbiologia , Masculino , Feminino , Pessoa de Meia-Idade , Helicobacter pylori/efeitos dos fármacos , Antibacterianos/uso terapêutico , Incidência , Idoso , Adulto , Fatores de Risco , Países Escandinavos e Nórdicos/epidemiologia , Inibidores da Bomba de Prótons/uso terapêutico , Inibidores da Bomba de Prótons/efeitos adversos , Medição de Risco , Sistema de Registros
11.
Surg Case Rep ; 10(1): 64, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494556

RESUMO

BACKGROUND: Pulmonary sarcomatoid carcinoma (PSC) is a rare and highly malignant type of non-small cell lung cancer (NSCLC), for which the treatment of choice is surgery. For peripheral PSC growing outward and invading the chest wall, a complete resection of the affected lung lobes and the invaded chest wall can improve long-term prognosis. However, when the extent of the resected chest wall is large, reconstruction is often required to reduce the risk of postoperative complications. Here, we present a case of PSC invading the chest wall treated with successful extended radical resection for lung cancer and chest wall reconstruction. CASE PRESENTATION: A 58-year-old male patient with a nodule in the right upper lobe that had been identified on physical examination 2 years before presentation presented to our hospital with a recent cough, expectoration, and chest pain. Imaging revealed a mass in the right upper lobe that had invaded the chest wall. Preoperative puncture pathology revealed poorly differentiated NSCLC. We performed extended radical resection for lung cancer under open surgery and reconstructed the chest wall using stainless steel wire and polypropylene meshes. The procedure was uneventful, and the patient was discharged 7 days postoperatively. Furthermore, the final pathology revealed PSC. CONCLUSIONS: This case underscores the feasibility of surgical R0 resection in patients with PSC with chest wall invasion and no lymph node metastasis, potentially enhancing long-term outcomes. The novel aspect of this case lies in the individualized chest wall reconstruction for a large defect, using cost-effective materials that offered satisfactory structural support and postoperative recovery, thereby providing a valuable reference for similar future surgical interventions.

12.
J Hazard Mater ; 466: 133632, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38309164

RESUMO

Due to the capacity to offer abundant catalytic sites within porous solids featuring high surface areas, metal-organic frameworks (MOFs) and their derivatives have garnered considerable attention as prospective catalysts in environmental catalysis. To promote the industrial application of MOFs, there is an urgent need for an effective and environmental-friendly preparation approach. Breaking through the limitation of the traditional two-step preparation method that Pd was introduced to the already prepared Ce-BTC (Pd/Ce-BTC, BTC = 1, 3, 5 benzenetricarboxylate), in this work, we present a novel one-pot solvothermal method for synthesizing the Pd material supported by Ce-BTC (Pd@Ce-BTC). After pyrolysis in N2 flow or air flow, Pd-CeO2 catalysts derived from Pd@Ce-BTC exhibited much higher CO oxidation activity than those from Pd/Ce-BTC. Moreover, Pd/Ce-BTC and Pd@Ce-BTC pyrolyzed in N2 flow (Pd/Ce-BTC-N and Pd@Ce-BTC-N) could better catalyze the oxidation of CO than Pd/Ce-BTC and Pd@Ce-BTC pyrolyzed in air flow (Pd/Ce-BTC-A and Pd@Ce-BTC-A). Further characterizations revealed that the abundant surface Ce3+ species, rich surface adsorbed oxygen species and superior redox properties were the main reasons for the superior CO oxidation activity of Pd@Ce-BTC-N.

13.
J Cardiothorac Surg ; 19(1): 8, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38173007

RESUMO

BACKGROUND: While the role of low-dose computed tomography (CT) in lung cancer screening is established, its limitations in detailing pulmonary vascular variations are less emphasized. Three-dimensional reconstruction technology allows surgeons to reconstruct a patient's bronchial and pulmonary vascular structures using CT scan results. However, low-dose CT may not provide the same level of clarity as enhanced CT in displaying pulmonary vascular details. This limitation can be unfavorable for preoperative detection of potential pulmonary vascular variations, especially in cases involving planned segmentectomy. CASE PRESENTATION: We report a case of a 58-year-old female with lung cancer, initially planned for Da Vinci robot-assisted thoracoscopic segmentectomy. Unexpectedly, during surgery, a pulmonary vein variation in the right upper lobe was discovered, leading to a change in the surgical method to a lobectomy. The patient had four variant right upper lobe veins draining into the superior vena cava and one into the left atrium. The surgery was complicated by significant bleeding and postoperative pulmonary congestion. Postoperative pathology confirmed adenocarcinoma. CONCLUSIONS: This case highlights the importance of meticulous intraoperative exploration, particularly in cases involving planned segmentectomy, as unexpected pulmonary vein variations can significantly affect surgical decision-making. While three-dimensional reconstruction based on preoperative CT data is a valuable tool, it may not capture the full complexity of the anatomical variations. We discuss potential preoperative imaging techniques, including contrast-enhanced CT and CT angiography, as methods to better identify these variations. The enhanced visualization provided by robot-assisted surgery plays a crucial role in identifying and adapting to these variations, underscoring the advantages of this surgical approach. Our report contributes to the existing literature by providing a detailed account of how these principles were applied in a real-world scenario, reinforcing the need for surgical adaptability and awareness of the limitations of low-dose CT in complex cases.


Assuntos
Neoplasias Pulmonares , Veias Pulmonares , Procedimentos Cirúrgicos Robóticos , Malformações Vasculares , Feminino , Humanos , Pessoa de Meia-Idade , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Veias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Veia Cava Superior/patologia , Detecção Precoce de Câncer , Pneumonectomia/métodos , Cirurgia Torácica Vídeoassistida/métodos , Malformações Vasculares/cirurgia
14.
ACS Appl Mater Interfaces ; 16(1): 454-466, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38147632

RESUMO

Fine-tuning the dispersion of active metal species on widely used supports is a research hotspot in the catalysis community, which is vital for achieving a balance between the atomic utilization efficiency and the intrinsic activity of active sites. In this work, using bayerite Al(OH)3 as support directly or after precalcination at 200 or 550 °C, Pt/Al2O3 catalysts with distinct Pt dispersions from single atoms to clusters (ca. 2 nm) were prepared and evaluated for CO and NH3 removal. Richer surface hydroxyl groups on AlOx(OH)y support were proved to better facilitate the dispersion of Pt. However, Pt/Al2O3 with relatively lower Pt dispersion could exhibit better activity in CO/NH3 oxidation reactions. Further reaction mechanism study revealed that the Pt sites on Pt/Al2O3 with lower Pt dispersion could be activated to Pt0 species much easier under the CO oxidation condition, on which a higher CO adsorption capacity and more efficient O2 activation were achieved simultaneously. Compared to Pt single atoms, PtOx clusters could also better activate NH3 into -NH2 and -HNO species. The higher CO adsorption capacity and the more efficient NH3/O2 activation ability on Pt/Al2O3 with relatively lower Pt dispersion well explained its higher CO/NH3 oxidation activity. This study emphasizes the importance of avoiding a singular pursuit of single-atom catalyst synthesis and instead focusing on achieving the most effective Pt species on Al2O3 support for targeted reactions. This approach avoids unnecessary limitations and enables a more practical and efficient strategy for Pt catalyst fabrication in emission control applications.

15.
Environ Sci Technol ; 58(1): 883-894, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38134887

RESUMO

Transition metal catalysts, such as copper oxide, are more attractive alternatives to noble metal catalysts for emission control due to their higher abundance, lower cost, and excellent catalytic activity. In this study, we report the preparation and application of a novel CuO/CeO2 catalyst using a hydroxyl-rich Ce(OH)x support for CO oxidation and NO reduction by CO. Compared to the catalyst prepared from a regular CeO2 support, the new CuO/CeO2 catalyst prepared from the OH-rich Ce(OH)x (CuO/CeO2-OH) showed significantly higher catalytic activity under different testing conditions. The effect of OH species in the CeO2 support on the catalytic performance and physicochemical properties of the CuO/CeO2 catalyst was characterized in detail. It is demonstrated that the abundant OH species enhanced the CuOx dispersion on CeO2, increased the CuOx-CeO2 interfaces and surface defects, promoted the oxygen activation and mobility, and boosted the NO adsorption and dissociation on CuO/CeO2-OH, thus contributing to its superior catalytic activity for both CO oxidation and NO reduction by CO. These results suggest that the OH-rich Ce(OH)x is a superior support for the preparation of highly efficient metal catalysts for different applications.


Assuntos
Elementos de Transição , Oxirredução , Oxigênio , Radical Hidroxila , Catálise
17.
Environ Sci Technol ; 57(41): 15747-15758, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37788364

RESUMO

Aiming at the development of an efficient NH3 oxidation catalyst to eliminate the harmful NH3 slip from the stationary flue gas denitrification system and diesel exhaust aftertreatment system, a facile ZrO2 doping strategy was proposed to construct Pt1/CexZr1-xO2 catalysts with a tunable Pt-CeO2 interaction strength and Pt-O-Ce coordination environment. According to the results of systematic characterizations, Pt species supported on CexZr1-xO2 were mainly in the form of single atoms when x ≥ 0.7, and the strength of the Pt-CeO2 interaction and the coordination number of Pt-O-Ce bond (CNPt-O-Ce) on Pt1/CexZr1-xO2 showed a volcanic change as a function of the ZrO2 doping amount. It was proposed that the balance between the reasonable concentration of oxygen defects and limited surface Zr-Ox species well accounted for the strongest Pt-CeO2 interaction and the highest CNPt-O-Ce on Pt/Ce0.9Zr0.1O2. It was observed that the Pt/Ce0.9Zr0.1O2 catalyst exhibited much higher NH3 oxidation activity than other Pt/CexZr1-xO2 catalysts. The mechanism study revealed that the Pt1 species with the stronger Pt-CeO2 interaction and higher CNPt-O-Ce within Pt/Ce0.9Zr0.1O2 could better activate NH3 adsorbed on Lewis acid sites to react with O2 thus resulting in superior NH3 oxidation activity. This work provides a new approach for designing highly efficient Pt/CeO2 based catalysts for low-temperature NH3 oxidation.


Assuntos
Amônia , Platina , Amônia/química , Oxirredução , Zircônio/química , Oxigênio , Catálise
18.
Cancer Med ; 12(21): 20544-20553, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37855240

RESUMO

BACKGROUND: Worldwide, gastric cancer is a leading cause of cancer incidence and mortality. This study aims to devise and validate a scoring system based on readily available clinical data to predict the risk of gastric cancer in a large Chinese population. METHODS: We included a total of 6,209,697 subjects aged between 18 and 70 years who have received upper digestive endoscopy in Hong Kong from 1997 to 2018. A binary logistic regression model was constructed to examine the predictors of gastric cancer in a derivation cohort (n = 4,347,224), followed by model evaluation in a validation cohort (n = 1,862,473). The algorithm's discriminatory ability was evaluated as the area under the curve (AUC) of the mathematically constructed receiver operating characteristic (ROC) curve. RESULTS: Age, male gender, history of Helicobacter pylori infection, use of proton pump inhibitors, non-use of aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), and statins were significantly associated with gastric cancer. A scoring of ≤8 was designated as "average risk (AR)". Scores at 9 or above were assigned as "high risk (HR)". The prevalence of gastric cancer was 1.81% and 0.096%, respectively, for the HR and LR groups. The AUC for the risk score in the validation cohort was 0.834, implying an excellent fit of the model. CONCLUSIONS: This study has validated a simple, accurate, and easy-to-use scoring algorithm which has a high discriminatory capability to predict gastric cancer. The score could be adopted to risk stratify subjects suspected as having gastric cancer, thus allowing prioritized upper digestive tract investigation.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Masculino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/complicações , Anti-Inflamatórios não Esteroides , Fatores de Risco , Algoritmos
19.
Environ Sci Technol ; 57(43): 16685-16694, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37864569

RESUMO

Selective catalytic reduction of NOx by NH3 (NH3-SCR) for diesel emission control at low temperatures is still a great challenge due to the limit of the urea injection threshold and inferior SCR activity of state-of-the-art catalyst systems below 200 °C. Fabricating bifunctional catalysts with both low temperature NOx adsorption-storage capacity and medium-high temperature NOx reduction activity is an effective strategy to solve the issues mentioned above but is rarely investigated. Herein, the WO3/Ce0.68Zr0.32Ox (W/CZ) catalyst containing the κ-Ce2Zr2O8 pyrochlore structure was successfully developed by a simple H2 reduction method, not only showing superior NOx adsorption-storage ability below 180 °C but also exhibiting excellent NH3-SCR activity above 180 °C. The presence of the pyrochlore structure effectively increased the oxygen vacancies on the κ-Ce2Zr2O8-containing W/CZ catalyst with enhanced redox property, which significantly promoted the NOx adsorption-storage as active nitrate species below 180 °C. Upon NH3 introduction above 180 °C, the κ-Ce2Zr2O8-containing W/CZ catalyst showed greatly improved NOx reduction performance, suggesting that the pyrochlore structure played a vital role in improving the NOx adsorption-selective catalytic reduction (AdSCR) performance. This work provides a new perspective for designing bifunctional CeZrOx-based catalysts to efficiently control the NOx emissions from diesel engines during the cold-start process.


Assuntos
Amônia , Nióbio , Adsorção , Amônia/química , Oxirredução , Catálise
20.
ACS Appl Mater Interfaces ; 15(37): 43756-43766, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37695888

RESUMO

Galvanic exchange seeds the growth of Pt nanostructures on the Ni foam monolith. Subsequent atomic layer deposition of ultrathin Al2O3 followed by annealing under air affords supported Pt catalysts with ultralow loading (0.020 ppm). In addition to the expected enhancement of the stability of the Pt particles on the surface, the ∼2 nm Al2O3 overcoat appears to also play a crucial role in the overall structural integrity of the NiOx nanoplates that grow on the Ni foam surface as a result of the preparative route. The resulting material is physically robust toward repeated handling and showcases retention of catalytic activity over 10 standard catalyst recycling trials, standing in marked contrast to the uncoated samples. Catalyst activity was tested via the hydrogenation of various functionalized styrenes at low temperatures and low hydrogen pressure in ethanol as a solvent, with a TOF as high as 9.5 × 106 h-1 for unfunctionalized styrene. Notably, the catalysts show excellent tolerance toward F, Cl, and Br substituents and no hydrogenation of the aromatic ring.

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