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1.
Sensors (Basel) ; 24(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39275466

RESUMEN

China's rail transit system is developing rapidly, but achieving seamless high-precision localization of trains throughout the entire route in closed environments such as tunnels and culverts still faces significant challenges. Traditional localization technologies cannot meet current demands, and the present paper proposes an autonomous localization method for trains based on pulse observation in a tunnel environment. First, the Letts criterion is used to eliminate abnormal gyro data, the CEEMDAN method is employed for signal decomposition, and the decomposed signals are classified using the continuous mean square error and norm method. Noise reduction is performed using forward linear filtering and dynamic threshold filtering, respectively, maximizing the retention of its effective signal components. A SINS/OD integrated localization model is established, and an observation equation is constructed based on velocity matching, resulting in an 18-dimensional complex state space model. Finally, the EM algorithm is used to address Non-Line-Of-Sight and multipath effect errors. The optimized model is then applied in the Kalman filter to better adapt to the system's observation conditions. By dynamically adjusting the noise covariance, the localization system can continue to maintain continuous high-precision position information output in a tunnel environment.

2.
Environ Sci Technol ; 57(51): 21866-21875, 2023 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-38095886

RESUMEN

Vanadium-based catalysts play a pivotal role in the emission control of industrial NOx via selective catalytic reduction (SCR) technology. However, little attention has been paid to the potential emission of greenhouse gas N2O under complex working conditions. This work reports that a commercial V2O5/TiO2 catalyst may lead to significant N2O emission without greatly changing the outlet NOx concentration after chromium (Cr) deposition. With a Cr loading of 2 wt %, N2O concentration increased from 27.8 to 199.2 ppm at 350 °C with the value of outlet N2O/(N2O+N2) from 2.5% to 19.4%. Experimental results combined with DFT+U calculations suggest that nonselective catalytic reduction (NSCR) is the main route for N2O formation in a wide temperature range of 250 ∼ 400 °C. It is stemmed from the fact that the covalent interaction between Cr and V species on the V2O5/TiO2 surface accelerates the conversion of V4+ + Cr6+ → V5+ + Cr3+, leading to a larger proportion of surface V5+. More importantly, surface V5+ is highly related to the redox property of the V2O5/TiO2 catalyst, which is beneficial to NSCR reaction rather than the standard SCR process. The work suggests that to better inhibit the emission of greenhouse gases during the NH3-SCR process, monitoring N2O emission should be included along with the NOx concentrations, especially in complex flue gases.


Asunto(s)
Gases de Efecto Invernadero , Titanio , Óxidos de Nitrógeno , Oxidación-Reducción , Catálisis , Gases , Amoníaco
3.
Environ Sci Technol ; 56(13): 9702-9711, 2022 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-35709381

RESUMEN

The crystal structure of TiO2 strongly influences the physiochemical properties of supported active sites and thus the catalytic performance of the as-synthesized catalyst. Herein, we synthesized TiO2 with different crystal forms (R = rutile, A = anatase, and B = brookite), which were used as supports to prepare vanadium-based catalysts for Hg0 oxidation. The Hg0 oxidation efficiency over V2O5/TiO2-B was the best, followed by V2O5/TiO2-A and V2O5/TiO2-R. Further experimental and theoretical results indicate that gaseous Hg0 reacts with surface-active chlorine species produced by the adsorbed HCl and the reaction orders of Hg0 oxidation over V2O5/TiO2 catalyst with respect to HCl and Hg0 concentration were approximately 0 and 1, respectively. The excellent Hg0 oxidation efficiency over V2O5/TiO2-B can be attributed to lower redox temperature, larger HCl adsorption capacity, and more oxygen vacancies. This work suggests that to achieve the best simultaneous removal of NOx and Hg0 on state-of-the-art V2O5/TiO2 catalyst, a combination of anatase and brookite TiO2-supported vanadyl tandem catalysts is supposed to be employed in the SCR reactor, and the brookite-type catalyst should be on the downstream of the anatase-based catalyst due to the inhibition of NH3 on Hg0 oxidation.

4.
Clin Exp Dermatol ; 47(11): 2043-2045, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35906074

RESUMEN

Pityriasis rubra pilaris (PRP) is a rare, scaly, keratotic inflammatory skin disease characterized by red scaly patches, keratosis papules, palmoplantar keratoderma and scaling of the scalp. In severe cases, ectropion of the eyelid may occur, and erythroderma may further develop. Recently, it has been reported that secukinumab, a monoclonal anti-interleukin-17A antibody, has certain efficacy in the treatment of PRP. Herein, we report a 3-year-old Chinese boy with severe Type III (classic juvenile) PRP who was successfully treated with secukinumab alone.


Asunto(s)
Queratodermia Palmoplantar , Pitiriasis Rubra Pilaris , Humanos , Masculino , Preescolar , Pitiriasis Rubra Pilaris/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Piel
5.
Dermatology ; 237(4): 603-610, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33352561

RESUMEN

BACKGROUND: Topical agents are still the mainstay for the treatment of mild-to-moderate plaque psoriasis, in which fixed combinations play an important role. Tazarotene/betamethasone dipropionate (Taz/BD) cream is a novel fixed combination approved for treating plaque psoriasis in China, but its efficacy and safety have not been verified in a real-world environment. OBJECTIVES: The primary objective was to investigate the efficacy and safety of Taz/BD cream in treating plaque psoriasis. The secondary objectives were to assess its relapse after discontinuation and the efficacy and safety profiles during retreatment. METHODS: A prospective, multicenter, large-scale observational study was conducted. Adult patients with chronic plaque psoriasis involving <20% of the body surface area were enrolled. Taz/BD cream was applied once daily for 4 weeks. Patients who achieved ≥90% improvement in the Psoriasis Area and Severity Index (PASI) from baseline to week 4 were followed up to investigate relapse after drug withdrawal. Relapsed patients underwent another 4-week treatment. RESULTS: In total, 2,299 eligible patients were enrolled, and 2,095 patients (91.1%) completed the 4-week study. The mean PASI improvement at week 4 was 53.7%, and the PASI 50/75 response rates were 62.5 and 26.8%, respectively. The mean PASI reduction in plaque induration, desquamation and erythema were 58.3, 61.0 and 40.0%, respectively (p < 0.001). Adverse reactions occurred in 445 patients (20.8%) at week 4. The most frequently reported adverse reactions were local skin irritation, including pruritus (10%), pain (6.7%), erythema (6.1%) and desquamation (1.8%). During the post-treatment period, 47 patients (24.0%) relapsed within 8 weeks after drug discontinuation. Forty-five patients were retreated for another 4 weeks, and the PASI 50/75 response rates were 72.7 and 40.9%, respectively. There were no unexpected safety signals during retreatment. CONCLUSION: Taz/BD cream is effective and well tolerated in treating mild-to-moderate plaque psoriasis under near real-world conditions and demonstrates efficacy and safety during retreatment.


Asunto(s)
Antiinflamatorios/uso terapéutico , Betametasona/análogos & derivados , Fármacos Dermatológicos/uso terapéutico , Ácidos Nicotínicos/uso terapéutico , Psoriasis/tratamiento farmacológico , Administración Cutánea , Adulto , Antiinflamatorios/administración & dosificación , Betametasona/efectos adversos , Betametasona/uso terapéutico , Fármacos Dermatológicos/administración & dosificación , Combinación de Medicamentos , Eritema/inducido químicamente , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ácidos Nicotínicos/efectos adversos , Dolor/inducido químicamente , Estudios Prospectivos , Prurito/inducido químicamente , Recurrencia , Retratamiento/efectos adversos , Índice de Severidad de la Enfermedad , Crema para la Piel
6.
Angew Chem Int Ed Engl ; 60(51): 26747-26754, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34665490

RESUMEN

Modulation of A-site defects is crucial to the redox reactions on ABO3 perovskites for both clean air application and electrochemical energy storage. Herein we report a scalable one-pot strategy for in situ regulation of La vacancies (VLa ) in LaMnO3.15 by simply introducing urea in the traditional citrate process, and further reveal the fundamental relationship between VLa creation and surface lattice oxygen (Olatt ) activation. The underlying mechanism is shortened Mn-O bonds, decreased orbital ordering, promoted MnO6 bending vibration and weakened Jahn-Teller distortion, ultimately realizing enhanced Mn-3d and O-2p orbital hybridization. The LaMnO3.15 with optimized VLa exhibits order of magnitude increase in toluene oxidation and ca. 0.05 V versus RHE (reversible hydrogen electrode) increase of half-wave potential in oxygen reduction reaction (ORR). The reported strategy can benefit the development of novel defect-meditated perovskites in both heterocatalysis and electrocatalysis.

8.
ScientificWorldJournal ; 2014: 517242, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25143983

RESUMEN

By using a high-order accurate finite difference scheme, direct numerical simulation of hypersonic flow over an 8° half-wedge-angle blunt wedge under freestream single-frequency entropy disturbance is conducted; the generation and the temporal and spatial nonlinear evolution of boundary layer disturbance waves are investigated. Results show that, under the freestream single-frequency entropy disturbance, the entropy state of boundary layer is changed sharply and the disturbance waves within a certain frequency range are induced in the boundary layer. Furthermore, the amplitudes of disturbance waves in the period phase are larger than that in the response phase and ablation phase and the frequency range in the boundary layer in the period phase is narrower than that in these two phases. In addition, the mode competition, dominant mode transformation, and disturbance energy transfer exist among different modes both in temporal and in spatial evolution. The mode competition changes the characteristics of nonlinear evolution of the unstable waves in the boundary layer. The development of the most unstable mode along streamwise relies more on the motivation of disturbance waves in the upstream than that of other modes on this motivation.


Asunto(s)
Entropía , Modelos Teóricos , Transferencia de Energía
9.
Cancer Imaging ; 24(1): 45, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549132

RESUMEN

BACKGROUND/PURPOSE: Risk factors for re-bleeding and death after acute variceal bleeding (AVB) in cirrhotic HCC patients are not fully understood.We aimed to (1) explore how the combination of high-risk esophageal varices, HCC status, and portal vein tumor thrombus (i.e., HCC Portal Hypertension Imaging Score [HCCPHTIS]) helps predict increased risk of variceal re-bleeding and mortality; (2) assess predictability and reproducibility of the identified variceal re-bleeding rules. METHODS: This prospective study included 195 HCC patients with first-time AVB and liver cirrhosis, and conducted multivariable Cox regression analysis and Kaplan-Meier analysis. Receiver operating characteristic curve analysis was calculated to find the optimal sensitivity, specificity, and cutoff values of the variables. The reproducibility of the results obtained was verified in a different but related group of patients. RESULTS: 56 patients (28.7%) had re-bleeding within 6 weeks; HCCPHTIS was an independent risk factor for variceal re-bleeding after AVB (Odd ratio, 2.330; 95% confidence interval: 1.728-3.142, p < 0.001). The positive predictive value of HCCPHTIS cut off value > 3 was 66.2%, sensitivity 83.9%, and specificity 82.3%. HCCPHTIS area under the curve was higher than Child-Pugh score (89% vs. 75%, p < 0.001). 74(37.9%) death occurred within 6 weeks; HCCPHTIS > 4 was associated with increased risk of death within 6 weeks after AVB (p < 0.001). CONCLUSION: HCCPHTIS > 3 is a strong predictor of variceal re-bleeding within the first 6 weeks. However, patients with HCCPHTIS > 4 were at increased risk of death within 6 weeks.


Asunto(s)
Carcinoma Hepatocelular , Várices Esofágicas y Gástricas , Hipertensión Portal , Neoplasias Hepáticas , Humanos , Várices Esofágicas y Gástricas/etiología , Várices Esofágicas y Gástricas/complicaciones , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/complicaciones , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/diagnóstico por imagen , Estudios Prospectivos , Reproducibilidad de los Resultados , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/diagnóstico por imagen , Hipertensión Portal/complicaciones , Hipertensión Portal/diagnóstico por imagen , Cirrosis Hepática/complicaciones , Tomografía Computarizada por Rayos X/efectos adversos
10.
J Hazard Mater ; 454: 131489, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37116325

RESUMEN

Ce-modified commercial vanadium-based catalysts are still in a rapid development stage in terms of optimizing Hg0 oxidation performance. Due to the universal property of ceria, it can act as either support or promoter to supported vanadium-based catalysts. However, the introduction mode of Ce on the Hg0 oxidation is still unclarified. Herein, introducing Ce to vanadium-based catalysts as a promoter (VCe/Ti) plays a more effective role in the Hg0 oxidation than only doping Ce into TiO2 support (V/CeTi). It is revealed that the strong interaction between V and Ce increases the orbital hybridization, and reduces the lowest unoccupied molecular orbital (LUMO) of V, which is conducive to adsorbing and activating HCl. The excellent performance of the VCe/Ti catalyst can be ascribed to its superior redox ability, stronger HCl adsorption capacity, abundant surface oxygen vacancies, and the redox equilibrium (Ce3+ + V5+ ↔ Ce4+ + V4+), which improves electron transfer, and thus the catalytic activity. This work provides the potential application of Ce-modified V-based catalysts for the simultaneous control of NOx and Hg0 in stationary sources.

11.
Nat Commun ; 14(1): 3477, 2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37311800

RESUMEN

The spillover of oxygen species is fundamentally important in redox reactions, but the spillover mechanism has been less understood compared to that of hydrogen spillover. Herein Sn is doped into TiO2 to activate low-temperature (<100 °C) reverse oxygen spillover in Pt/TiO2 catalyst, leading to CO oxidation activity much higher than that of most oxide-supported Pt catalysts. A combination of near-ambient-pressure X-ray photoelectron spectroscopy, in situ Raman/Infrared spectroscopies, and ab initio molecular dynamics simulations reveal that the reverse oxygen spillover is triggered by CO adsorption at Pt2+ sites, followed by bond cleavage of Ti-O-Sn moieties nearby and the appearance of Pt4+ species. The O in the catalytically indispensable Pt-O species is energetically more favourable to be originated from Ti-O-Sn. This work clearly depicts the interfacial chemistry of reverse oxygen spillover that is triggered by CO adsorption, and the understanding is helpful for the design of platinum/titania catalysts suitable for reactions of various reactants.

12.
Chemosphere ; 307(Pt 1): 135654, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35863410

RESUMEN

Bilge water is a significant source of pollution in the marine environment and has captured widespread international attention. In this study, a sequencing batch reactor (SBR) combined with strain S2 identified as Bacillus licheniformis was employed to assess the biodegradation of Chemical Oxygen Demand (COD) from bilge water. The influencing variables such as temperature, pH level and inoculum concentration on the performance SBR system were optimized by utilizing response surface methodology (RSM). The experimental results showed that the maximum COD removal of 77.81% was reached at the optimal SBR operation conditions of temperature 35.44 °C pH 8.13, and inoculum concentration 31.47 mL. In the practical application of SBR, it was found that the decrease in hydraulic retention time (HRT) was accompanied by a decrease in COD degradation rate. The biodegradation kinetics of COD in bilge water were well fitted with the first-order equation with a higher R2 value of 0.98106. In conclusion, COD in bilge water can be efficiently biodegraded by SBR under the optimization of RSM.


Asunto(s)
Reactores Biológicos , Contaminantes Químicos del Agua , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Eliminación de Residuos Líquidos/métodos , Agua , Contaminantes Químicos del Agua/metabolismo
13.
Mol Clin Oncol ; 13(5): 59, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32953113

RESUMEN

The aim of the present study was to present a rare case of primary acral amelanotic malignant melanoma (AMM). A 61-year-old man developed an aggressive tumor in the front part of the sole of his left foot, which continued to increase in size for >1 year. The biopsy results revealed epidermis loss, ulcer formation, and the presence of abundant allotropic tumor cells throughout the dermis, with deeply stained nuclei, light reddish cytoplasm and visible multinucleated giant cells with heterogeneous nuclear division. The tumor cells exhibited partial formation of nests and bundled distribution, and there were no observed pigment particles. The diagnosis was confirmed as AMM based on the findings of the histopathological examination and immunohistochemical staining for Ki67 (+++), Melan-A (+++), human melanoma black 45 (+), CD20 (-), cytokeratin (CK)7 (-) and CK5/6 (-).

17.
Cell Biosci ; 5: 73, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26705467

RESUMEN

BACKGROUND: Systemic lupus erythematosus (SLE) is a prototypic systemic autoimmune disease. Complement component 4 (C4) has be proved to play a role in pathogenesis of SLE. In the present study, we investigated the effect of C4 on T cells differentiation. METHODS: Thirty SLE patients were included in this study. CD4+ T cells were isolated from healthy subjects, and dendritic cells (DCs) were isolated from healthy subjects or SLE patients. C4 was supplemented to co-incubate with T cells and DCs. RESULTS: Serum C4 concentration was positively correlated with regulatory T cell (Treg) percentage (R(2) = 0.5907, p < 0.001) and TGFß concentration (R(2) = 0.5641, p < 0.001) in SLE patients. Different concentrations of C4 had no effect on T cells differentiation. Co-incubated T cells with DCs and C4 for 7 days, the Treg percentage and TGF-ß concentration were significantly elevated. In addition, pre-treated DCs (from healthy subjects or SLE patients) with C4 and then co-incubated with T cells, the increases of Treg percentage and TGF-ß concentration were also observed. CONCLUSION: C4 takes part in T cells differentiation to Treg cells via DCs.

18.
Oncotarget ; 6(40): 42825-37, 2015 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-26517517

RESUMEN

Mesenchymal stem cells (MSCs) have recently been shown to home to tumors and contribute to the formation of the tumor-associated stroma. In addition, MSCs can secrete paracrine factors to facilitate tumor progression. However, the involvement of MSC-derived cytokines in colorectal cancer (CRC) angiogenesis and growth has not been clearly addressed. In this study, we report that interleukin-8 (IL-8) was the most highly upregulated pro-angiogenic factor in MSCs co-cultured with CRC cells and was expressed at substantially higher levels in MSCs than CRC cells. To evaluate the effect of MSC-derived IL-8 on CRC angiogenesis and growth, we used MSCs that expressed small hairpin (interfering) RNAs (shRNA) targeting IL-8 (shIL-8-MSCs). We found that MSC-secreted IL-8 promoted human umbilical vein endothelial cell (HUVEC) proliferation and migration, tube-formation ability and CRC cell proliferation. Additionally, in vivo studies showed that MSCs promoted tumor angiogenesis partially through IL-8. Taken together, these findings suggest that IL-8 secreted by MSCs promotes CRC angiogenesis and growth and can therefore serve as a potential novel therapeutic target.


Asunto(s)
Neoplasias Colorrectales/patología , Interleucina-8/metabolismo , Células Madre Mesenquimatosas/metabolismo , Neovascularización Patológica/metabolismo , Animales , Células de la Médula Ósea/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Neoplasias Colorrectales/metabolismo , Medios de Cultivo Condicionados/farmacología , Ensayo de Inmunoadsorción Enzimática , Xenoinjertos , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Humanos , Inmunohistoquímica , Ratones , Ratones Desnudos , Neovascularización Patológica/patología , ARN Interferente Pequeño , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
19.
Indian J Dermatol ; 59(1): 91-3, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24470671

RESUMEN

A 14-year-old Chinese girl had a 6-year history of recurrent lesions on her head, face, and limbs. Epstein-Barr virus (EBV)-IgM was positive. Histopathological findings revealed focal lymphocyte invasion in subcutaneous panniculus adiposus, mainly surrounding the blood vessels. Immunohistochemistry showed CD3+, CD4+, CD5+, CD8+, TIA-1+, GrB+, CD56-, and L26-. In situ hybridization staining for EBV-encoded small nonpolyadenylated RNA (EBER)-1 was positive. The patient showed significant improvement in clinical symptoms after being treated with acyclovir and IFN-α in this patient.

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