Methane is the most stable hydrocarbon with a regular tetrahedral structure, which can be activated and oxidized above 1000 °C in conventional combustion. Catalytic oxidation is an effective way to ...eliminate lean methane under mild conditions, and the key issue is to develop the catalysts with high efficiencies, good stability, and high selectivities. Catalytic combustion of low-concentration methane can realize the light-off and deep conversion at low temperatures, thus achieving complete combustion with fewer byproducts below 500 °C. This review article summarizes the recent advances in preparation of ordered porous oxides and supported noble metal catalysts and their methane combustion applications. The results reveal that the superior performance (good hydrothermal stability and excellent moisture- or sulfur-resistant behavior) is associated with the well-ordered and developed three-dimensional porous structure, large surface area, ultrahigh component dispersion, fast mass transfer, low-temperature reducibility, reactant activation ability, and strong interaction between metal and support. In addition, the development trend of porous oxides for industrial applications in the future is also proposed.
Zeolites have ordered pore structures, good spatial constraints, and superior hydrothermal stability. In addition, the active metal elements inside and outside the zeolite framework provide the ...porous material with adjustable acid–base property and good redox performance. Thus, zeolites-based catalysts are more and more widely used in chemical industries. Combining the advantages of zeolites and active metal components, the zeolites-based materials are used to catalyze the oxidation of methane to produce various products, such as carbon dioxide, methanol, formaldehyde, formic acid, acetic acid, and etc. This multifunction, high selectivity, and good activity are the key factors that enable the zeolites-based catalysts to be used for methane activation and conversion. In this review article, we briefly introduce and discuss the effect of zeolite materials on the activation of C–H bonds in methane and the reaction mechanisms of complete methane oxidation and selective methane oxidation. Pd/zeolite is used for the complete oxidation of methane to carbon dioxide and water, and Fe- and Cu-zeolite catalysts are used for the partial oxidation of methane to methanol, formaldehyde, formic acid, and etc. The prospects and challenges of zeolite-based catalysts in the future research work and practical applications are also envisioned. We hope that the outcome of this review can stimulate more researchers to develop more effective zeolite-based catalysts for the complete or selective oxidation of methane.
Tumor microenvironment plays an important role in tumor proliferation, metastasis, and angiogenesis. Local RAS is a key factor to tumor proliferation and metastasis in NSCLC microenvironment, but its ...role on angiogenesis and VM formation remains unclear. Although overwhelming majority of previous studies suggested that VM is well established in aggressive tumor and facilitates tumor growth and metastasis, we put forward different views from another angle. We proved that status of tumor blood supply patterns, including VM channels and endothelial vessels, can dynamically exchange with each other along with local RAS fluctuations in microenvironment. Quantitatively, ACE2/ACEI promotes VM formation
via
Nodal/Notch4 activation; while structurally, ACE2/ACEI leads to a strong and solid structure of VM
via
inhibition of VE-cadherin internalization. These changes induced by ACE2/ACEI relate to relatively low metastasis rate and comforting prognoses of NSCLC patients.
With the continuous development of flexible transparent electrodes, silver nanowires have been widely used due to their excellent optoelectronic properties and flexibility. However, their progress ...has been hindered by high contact resistance. In this study, femtosecond laser post-processing was applied to the silver nanowire transparent electrodes, and the effect of laser power density on the welding of silver nanowires was investigated. The results showed that femtosecond laser could achieve welding between silver nanowires, but excessively high laser energy density could cause the melting of the nanowires. When the femtosecond laser energy density reached the critical energy density of approximately 2546 J·m−2, at which nanowires underwent spheroidization, the average sheet resistance of the silver nanowire electrodes was minimized to 18.89 Ω·sq−1, and the figure of merit (FoM) of the electrodes reached its maximum at 126.99, which was close to twice the initial value. Moreover, the non-uniformity factor (NUF) was also small, at 1.6%, indicating good conductivity and uniformity. Additionally, the influence of femtosecond laser irradiation on the transmittance of the silver nanowire transparent electrodes was insignificant, and the number of effective pulses had no obvious effect on the welding efficiency of the silver nanowires.
This study examines the antecedents of customers' willingness and objection to use artificially intelligent robotic devices in hospitality services (full-service and limited-service hotels). Drawing ...on the Artificially Intelligent Device Use Acceptance (AIDUA) theory, this study validates and extends the AIDUA framework in the hospitality service setting. The results point to the applicability of the AIDUA framework, suggesting that hospitality customers' intention to the use of artificially intelligent devices are influenced by social influence, hedonic motivation, anthropomorphism, performance and effort expectancy, and emotions toward the artificially intelligent devices. Findings further suggest that compared to limited-service hotel customers, full-service hotel customers rely less on their social groups when evaluating artificially intelligent robotic devices; their emotions toward the use of artificially intelligent devices are less likely to be influenced by effort expectancy; and their emotions cause less impact on their objection to the use. Theoretical contributions and managerial implications of this study are discussed. Limitations and future study recommendations are provided.
Abstract Purpose Antibiotic dosing in obese surgical patients has not been adequately evaluated. The objective of this study was to identify whether currently prescribed doses of cefoxitin achieve ...adequate and sustained plasma and tissue concentrations in obese patients undergoing sleeve gastrectomy. Methods A prospective evaluation of plasma and tissue cefoxitin concentrations in patients undergoing sleeve gastrectomy was performed. On the day of the surgical procedure, venous blood samples (5 mL) were collected just before cefoxitin administration and then at 5, 30, 60, 120, and 240 minutes after dose administration. In addition, subcutaneous adipose tissue was collected from the surgical site at the time of surgical incision and at closure. Cefoxitin concentrations in the collected samples were quantified by using an HPLC–ultraviolet method. A standard noncompartmental analysis was performed for each individual cefoxitin plasma concentration–time profile. In addition, the ratio of tissue to plasma concentration was calculated for all patients. Findings Plasma and tissue pharmacokinetics of cefoxitin were evaluated in 6 patients undergoing sleeve gastrectomy. The mean age and BMI were 48.7 (6.2) years and 42.8 (7.1) kg/m2 , respectively. At the time of surgical closure, subcutaneous adipose tissue concentrations of cefoxitin were subtherapeutic (<8 µg/mL) in all evaluated patients. Implications Current dosing strategies for cefoxitin in obese surgical patients may be inadequate, and there is an urgent need to define the appropriate dosage.
Immunosuppressed patients with bloodstream infection are at risk of mortality. Our objective was to assess the independent risk factors of bloodstream infection with mortality in immunosuppressive ...states.
The medical data of a total of 896 patients who were hospitalized in our hospital were collected from January 2015 to December 2019. Evaluation of the independent risk factors of mortality was done by univariate and multivariate logistic regression analyses.
Of the 896 immunosuppressed patients with bloodstream infection, 698 had over 60-day survivals and 198 had 60-day mortality. In our study, PCT (mean ±; standard: 11.40 ±; 31.89 µg/l vs. 62.45 ±; 17.10 µg/l, p = 0.007) and presence of age >60 years (40% vs. 14.19%, p = 0.001) were significantly different between situations with and without 60-day survivals in both univariate and multivariate logistic regression analyses. Age >60 years and PCT could be used as indicators for bloodstream infection with 60-day death in immunosuppressive states; the OR (95% CI) were 1.532 (1.099-2.135) and 2.063 (1.413-3.013), respectively. In different subgroups, PCT and age were also independent risk factors of blood system diseases,
infection, diabetes, and ICU-stay subgroups.
Age and PCT were independently associated with mortality in immunosuppressive states, which may help to identify the highly risky situation of bloodstream infection in immunosuppressive states.
Matriptase is a transmembrane serine protease, synthesized as an inactive single-chain zymogen on the endoplasmic reticulum and transported to the plasma membrane. Matriptase is activated in ...different epithelial and some B-cell malignancies and changes its conformation and activity is inhibited mainly by its endogenous inhibitor HAI-1. Activated matriptase plays a key role in tumor initiation as well as tumor progression, including invasiveness, and metastasis. To target the anti-mitotic toxin (monomethyl auristatin-E) to activated matriptase, a novel antibody to activated matriptase was conjugated with this toxin via a valine-citrulline-PABA linker. In a previous study, this antibody-toxin conjugate was found to be effective against triple negative breast cancer cell lines and xenografts, alone, or in combination with cisplatin (1). In this study, we examined the anti-tumor effect of the antibody toxin conjugate (ADC) against activated matriptase positive mantle cell lymphoma cell lines (JeKo-1, Maver, Mino, and Z138). This ADC was cytotoxic to these cell lines with IC
s between 5 and 14 μg/mL. The ADC also showed a dose dependent anti-tumor effect on the JeKo-1 xenograft in mice without toxicity.
Utilizing the Stimulus-Organism-Response paradigm, this study explores how self-disclosure, an important component of tourist-to-tourist interaction, influences tourist experience. Data were ...collected through a field experiment and analyzed via PLS analysis and PROCESS. Findings indicate that self-disclosure indirectly increases engagement by strengthening perceived cohesion and perceived intimacy. Perceived cohesion and perceived intimacy have indirect effects on satisfaction with experience, through engagement. Further, the initial tie strength moderates the effect of self-disclosure on perceived cohesion and perceived intimacy. These findings contribute to the development of tourism experience research from the perspective of tourist-to-tourist interaction and the social interaction literature by examining the unique interaction mechanism among tourists.
•Integrates tourist-to-tourist interaction into tourist experience studies.•Uses PLS analysis to examine data collected by field experiment in China.•Self-disclosure is a significant component of tourist-to-tourist interaction.•Perceived cohesion and intimacy are critical determinants of tourist engagement.•Engagement mediates the impacts of cohesion and intimacy on satisfaction.
The aim of this study was to assess the diagnostic value of several markers for tuberculosis pleural effusion (TPE) using the combined analysis of Lactate dehydrogenase (LDH), Carbohydrate antigen ...125 (CA125), Cytokeratin-19 fragment (CYFRA21-1).
From January to December in 2018, a total of 37 patients with pleural effusion (22 cases of transudative pleural effusion, 15 cases of tuberculosis pleural effusion and 22 cases of Transudative pleural effusion who were hospitalized in our hospital were reviewed. Receiver operating characteristic (ROC) curves and logistic regression equations was used to evaluate the diagnostic efficiency of each marker.
The levels of LDH and CYFRA21-1 of tuberculosis pleural effusions were obviously higher than those of transudative pleural effusion with statistically significant difference (<0.05). The areas under the ROC curve of LDH, CA125 and CYFRA21-1 were 0.92, 0.344 and 0.656, respectively. The diagnostic sensitivity of LDH, CA125 and CYFRA21-1 were 100%, 13.3%, 73.3%, respectively. The combined detection of LDH, CA125 and CYFRA21-1 were higher than those of any other combinations of the indexes.
The study showed a high diagnostic sensitivity and specificity of combined speculation of LDH, ADA and CYFRA21-1 in Tuberculosis pleural effusion.
El objetivo de este estudio fue evaluar el valor diagnóstico de diversos marcadores de derrame pleural tuberculoso (DPTB) utilizando el análisis combinado de lactato deshidrogenasa (LDH), antígeno carbohidrato 125 (CA-125) y fragmento de citoqueratina-19 (CYFRA 21-1).
De enero a diciembre de 2018, revisamos un total de 37 pacientes hospitalizados en nuestro hospital con derrame pleural (22 casos de derrame pleural trasudativo y 15 casos de derrame pleural tuberculoso). Se utilizaron las curvas ROC y ecuaciones de regresión logística para evaluar la eficacia diagnóstica de cada marcador.
Los niveles de LDH y CYFRA 21-1 de los pacientes con derrame pleural tuberculoso fueron obviamente superiores a los pacientes con derrame pleural trasudativo, con diferencia estadísticamente significativa (p<0,05). Las áreas bajo la curva ROC de LDH, CA-125 y CYFRA 21-1 fueron 0,92, 0,344 y 0,656, respectivamente. La sensibilidad diagnóstica de LDH, CA-125 y CYFRA 21-1 fueron del 100, 13,3 y 73,3%, respectivamente. La detección combinada de LDH, CA-125 y CYFRA 21-1 fue superior a cualesquiera otras combinaciones de los índices.
El estudio reflejó una alta sensibilidad diagnóstica y especificidad del análisis combinado de LDH, ADA y CYFRA 21-1 en el derrame pleural tuberculoso.