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1.
Environ Res ; 248: 118321, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38307186

RESUMEN

BACKGROUND: Metalloestrogens are metals and metalloid elements with estrogenic activity found everywhere. Their impact on human health is becoming more apparent as human activities increase. OBJECTIVE: Our aim is to conduct a comprehensive systematic review and meta-analysis of observational studies exploring the correlation between metalloestrogens (specifically As, Sb, Cr, Cd, Cu, Se, Hg) and Gestational Diabetes Mellitus (GDM). METHODS: PubMed, Web of Science, and Embase were searched to examine the link between metalloestrogens (As, Sb, Cr, Cd, Cu, Se, and Hg) and GDM until December 2023. Risk estimates were derived using random effects models. Subgroup analyses were conducted based on study countries, exposure sample, exposure assessment method, and detection methods. Sensitivity analyses and adjustments for publication bias were carried out to assess the strength of the findings. RESULTS: Out of the 389 articles identified initially, 350 met our criteria and 33 were included in the meta-analysis, involving 141,175 subjects (9450 cases, 131,725 controls). Arsenic, antimony, and copper exposure exhibited a potential increase in GDM risk to some extent (As: OR = 1.28, 95 % CI [1.08, 1.52]; Sb: OR = 1.73, 95 % CI [1.13, 2.65]; Cu: OR = 1.29, 95 % CI [1.02, 1.63]), although there is a high degree of heterogeneity (As: Q = 52.93, p < 0.05, I2 = 64.1 %; Sb: Q = 31.40, p < 0.05, I2 = 80.9 %; Cu: Q = 21.14, p < 0.05, I2 = 71.6 %). Conversely, selenium, cadmium, chromium, and mercury exposure did not exhibit any association with the risk of GDM in our study. DISCUSSION: Our research indicates that the existence of harmful metalloestrogens in the surroundings has a notable effect on the likelihood of GDM. Hence, we stress the significance of environmental elements in the development of GDM and the pressing need for relevant policies and measures.

2.
BMC Public Health ; 24(1): 1344, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762446

RESUMEN

Climate change increases the risk of illness through rising temperature, severe precipitation and worst air pollution. This paper investigates how monthly excess mortality rate is associated with the increasing frequency and severity of extreme temperature in Canada during 2000-2020. The extreme associations were compared among four age groups across five sub-blocks of Canada based on the datasets of monthly T90 and T10, the two most representative indices of severe weather monitoring measures developed by the actuarial associations in Canada and US. We utilize a combined seasonal Auto-regressive Integrated Moving Average (ARIMA) and bivariate Peaks-Over-Threshold (POT) method to investigate the extreme association via the extreme tail index χ and Pickands dependence function plots. It turns out that it is likely (more than 10%) to occur with excess mortality if there are unusual low temperature with extreme intensity (all χ > 0.1 except Northeast Atlantic (NEA), Northern Plains (NPL) and Northwest Pacific (NWP) for age group 0-44), while extreme frequent high temperature seems not to affect health significantly (all χ ≤ 0.001 except NWP). Particular attention should be paid to NWP and Central Arctic (CAR) since population health therein is highly associated with both extreme frequent high and low temperatures (both χ = 0.3182 for all age groups). The revealed extreme dependence is expected to help stakeholders avoid significant ramifications with targeted health protection strategies from unexpected consequences of extreme weather events. The novel extremal dependence methodology is promisingly applied in further studies of the interplay between extreme meteorological exposures, social-economic factors and health outcomes.


Asunto(s)
Mortalidad , Humanos , Canadá/epidemiología , Mortalidad/tendencias , Lactante , Adulto , Persona de Mediana Edad , Adolescente , Preescolar , Adulto Joven , Niño , Recién Nacido , Anciano , Cambio Climático , Masculino , Femenino , Clima Extremo
3.
Langmuir ; 39(32): 11426-11438, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37531465

RESUMEN

As a promising catalyst, MoS2 has been widely studied owing to its high chemical reactivity, excellent electrical carrier mobility, good optical properties, and narrow band gap. However, the high recombination rate of photoinduced charge carriers limits its practical application in photocatalysis. In this study, MoS2 was coupled with PANI to fabricate an S-scheme heterojunction MoS2/PANI. The synthesized products were characterized systematically, and their photocatalytic properties were evaluated by photocatalytic degradation of norfloxacin (NOR) and rhodamine B (RhB). The obtained results indicated that the fabricated MoS2/PANI inorganic-organic heterojunction displayed tremendously enhanced photocatalytic activity. The degradation efficiencies for 60 mg L-1 of NOR and RhB are 86 and 100% under the simulated sunlight irradiation for 1 h with 10 mg of catalyst, which are 13 and 47 times higher than those of pure MoS2, respectively. Interestingly, it is superior to the previously reported related materials. The remarkably enhanced photocatalytic activity of MoS2 is assigned to the high charge conductivity feature of PANI and the formed S-scheme heterojunction that result in a steric separation of holes and electrons and conserve the initial powerful redox ability of the parent catalysts. This study provides a facile method to greatly improve the photocatalytic activity of MoS2 and facilitates its application for highly efficient removal of organic pollutants, such as antibiotic drugs and organic dyes, utilizing solar energy.

4.
Mikrochim Acta ; 191(1): 41, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38112843

RESUMEN

A highly sensitive tumor necrosis factor α (TNF-α) detection method based on a surface-enhanced Raman scattering (SERS) magnetic patch sensor is reported. Magnetic beads (MNPs) and core shells were used as the capture matrix and signaling probe, respectively. For this purpose, antibodies were immobilized on the surface of magnetic beads, and then Au@4-MBN@Ag core-shell structures coupled with aptamers and TNF-α antigen were added sequentially to form a sandwich immune complex. Quantitative analysis was performed by monitoring changes in the characteristic SERS signal intensity of the Raman reporter molecule 4-MBN. The results showed that the limit of detection (LOD) of the proposed method was 4.37 × 10-15 mg·mL-1 with good linearity (R2 = 0.9918) over the concentration range 10-12 to 10-5 mg·mL-1. Excellent assay accuracy was also demonstrated, with recoveries in the range 102% to 114%. Since all reactions occur in solution and are separated by magnetic adsorption of magnetic beads, this SERS-based immunoassay technique solves the kinetic problems of limited diffusion and difficult separation on solid substrates. The method is therefore expected to be a good clinical tool for the diagnosis of the inflammatory biomarker THF-α and in vivo inflammation screening.


Asunto(s)
Aptámeros de Nucleótidos , Factor de Necrosis Tumoral alfa , Plata/química , Oro/química , Magnetismo , Aptámeros de Nucleótidos/química
5.
Small ; 18(2): e2104302, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34761867

RESUMEN

Here, acidic tumor microenvironment (TME)-responsive nano-Bi2 Se3 @MnCaP, as a near-infrared-II (NIR-II) biowindow-triggered free radical generator for hypoxia-irrelevant phototherapy, is elaborately developed by biomimetic mineralization of MnCaP onto 2, 2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH)-loaded mesoporous nano-Bi2 Se3 to form Bi2 Se3 /AIPH@MnCaP (BAM). Surface mineral of MnCaP can be degraded under mild acidity, leading to the release of both Mn2+ and AIPH. The leached Mn2+ not only facilitates chemodynamic therapy (CDT) via hydroxyl radicals (• OH) from Mn2+ -mediated Fenton-like reaction but also acts as contrast agent for magnetic resonance imaging. In another aspect, the splendid photothermal conversion capacity of BAM enables a rapid hyperthermia generation under NIR-II laser irradiation for photothermal therapy (PTT). Simultaneously, the local thermal shock can induce the disintegration of AIPH to generate alkyl radicals (• R) for thermodynamic therapy (TDT) and accelerate Fenton-like reaction rate to augment CDT efficacy. The strong synergistic effects from cooperative CDT/PTT/TDT are applied to 4T1 tumor suppression with minimal side effects. Importantly, the combination therapy can effectively trigger immunogenetic cell death and enhance antitumor immunity for systemic tumor eradication. Collectively, this proof-of-concept study demonstrates a more efficacious and safer strategy for oxygenation-independent phototherapy, which holds a good potential for clinical translation in cancer management.


Asunto(s)
Nanopartículas , Neoplasias , Línea Celular Tumoral , Radicales Libres , Humanos , Hipoxia/tratamiento farmacológico , Neoplasias/tratamiento farmacológico , Fototerapia , Microambiente Tumoral
6.
Langmuir ; 38(42): 12968-12980, 2022 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-36214811

RESUMEN

Norfloxacin (NOR) and tetracycline (TC), two widely used antibiotic drugs released to the aquatic environment, induce harm to ecosystems. In this study, an effective method was developed successfully to remove NOR and TC by photocatalysis with a novel heterojunction NC/NH2-MIL-53(Fe), which was fabricated by combining a metal-organic framework (MOF) material (NH2-MIL-53(Fe)) and N-doped carbon (NC) nanoparticles via a facile solvent thermal method. The prepared product exhibits outstanding photocatalytic efficiencies toward degradation of NOR and TC that are 15 and 6 times higher than those of pure NH2-MIL-53(Fe), respectively. Moreover, it is higher than those of the related materials reported previously. The greatly enhanced photocatalytic performance is assigned to the fabricated heterojunction with well-matched energy band gaps, where the NC acts as an efficient electron transfer/reservoir material to effectively promote the migration and transfer and restrain the recombination of charge carriers. In addition, the formed heterojunction increases specific surface area and light absorbance. The photocatalytic activity enhanced mechanism, degradation products, and pathway were investigated. The present study offers a novel strategy to significantly improve the photocatalytic performances of MOFs for highly efficient photocatalytic removal of antibiotic drugs in wastewater.


Asunto(s)
Estructuras Metalorgánicas , Norfloxacino , Aguas Residuales , Catálisis , Carbono , Ecosistema , Antibacterianos , Tetraciclina , Solventes
7.
Langmuir ; 38(15): 4680-4691, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35394281

RESUMEN

Covalent organic frameworks (COFs) exhibit visible-light activity for the degradation of organic pollutants. However, the recombination rates of their photoinduced electron-hole pairs are relatively high, limiting their practical application. In this work, we fabricated a 1,3,5-triformylphloroglucinol (Tp) and p-phenylenediamine (Pa-1) (TpPa-1) COF-based heterojunction through coupling the TpPa-1 COF with a ZnAgInS nanosphere via a facile oil bath heating method. The results show that the prepared heterojunction exhibits outstanding catalytic activity for the degradation of high concentrations the antibiotic tetracycline (TC) and the dye rhodamine B (RhB), which is driven by simulated sunlight. Its degradation rates for RhB and TC were 30× and 18× higher than that of the pure TpPa-1 COF, respectively. The greatly enhanced photocatalytic performances can be ascribed to the formed heterojunction with good band-gap match, which promotes the migration and separation of light-induced electrons and holes and increases both light absorbance and the specific surface area. This study introduces an effective and feasible strategy for improving the photocatalytic performances of COFs via subtly integrating TpPa-1 COFs with a ZnAgInS nanosphere into an organic-inorganic hybrid. The results of the photocatalytic experiments indicate that the fabricated hybrid has a potential application in the highly efficient removal of organic pollutants.

8.
Hepatobiliary Pancreat Dis Int ; 18(1): 38-47, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30243878

RESUMEN

BACKGROUND: Previous research suggested that insulin-like growth factor binding protein related protein 1 (IGFBPrP1), as a novel mediator, contributes to hepatic fibrogenesis. Matrix metalloproteinases (MMP) and tissue inhibitors of metalloproteinases (TIMP) play an essential role in hepatic fibrogenesis by regulating homeostasis and remodeling of the extracellular matrix (ECM). However, the interaction between IGFBPrP1 and MMP/TIMP is not clear. The present study was to knockdown IGFBPrP1 to investigate the correlation between IGFBPrP1 and MMP/TIMP in hepatic fibrosis. METHODS: Hepatic fibrosis was induced by thioacetamide (TAA) in mice. Knockdown of IGFBPrP1 expression by ultrasound-targeted microbubble destruction-mediated CMB-shRNA-IGFBPrP1 delivery, or inhibition of the Hedgehog (Hh) pathway by cyclopamine treatment, was performed in TAA-induced liver fibrosis mice. Hepatic fibrosis was determined by hematoxylin and eosin and Sirius red staining. Hepatic expression of IGFBPrP1, α-smooth muscle actin (α-SMA), transforming growth factor ß 1 (TGFß1), collagen I, MMPs/TIMPs, Sonic Hedgehog (Shh), and glioblastoma family transcription factors (Gli1) were investigated by immunohistochemical staining and Western blotting analysis. RESULTS: We found that hepatic expression of IGFBPrP1, TGFß1, α-SMA, and collagen I were increased longitudinally in mice with TAA-induced hepatic fibrosis, concomitant with MMP2/TIMP2 and MMP9/TIMP1 imbalance and Hh pathway activation. Knockdown of IGFBPrP1 expression, or inhibition of the Hh pathway, reduced the hepatic expression of IGFBPrP1, TGFß1, α-SMA, and collagen I and re-established MMP2/TIMP2 and MMP9/TIMP1 balance. CONCLUSIONS: Our findings suggest that IGFBPrP1 knockdown attenuates liver fibrosis by re-establishing MMP2/TIMP2 and MMP9/TIMP1 balance, concomitant with the inhibition of hepatic stellate cell activation, down-regulation of TGFß1 expression, and degradation of the ECM. Furthermore, the Hh pathway mediates IGFBPrP1 knockdown-induced attenuation of hepatic fibrosis through the regulation of MMPs/TIMPs balance.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Técnicas de Silenciamiento del Gen , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/genética , Cirrosis Hepática Experimental/prevención & control , Hígado/enzimología , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/genética , Inhibidor Tisular de Metaloproteinasa-1/genética , Inhibidor Tisular de Metaloproteinasa-2/genética , Actinas/genética , Actinas/metabolismo , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/enzimología , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Proteínas de Unión a Factor de Crecimiento Similar a la Insulina/deficiencia , Hígado/patología , Cirrosis Hepática Experimental/inducido químicamente , Cirrosis Hepática Experimental/enzimología , Cirrosis Hepática Experimental/genética , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIH , Transducción de Señal , Tioacetamida , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo
9.
Entropy (Basel) ; 21(2)2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-33266849

RESUMEN

In the development of tight gas reservoirs, gas flow through porous media usually takes place deep underground with multiple mechanisms, including gas slippage and stress sensitivity of permeability and porosity. However, little work has been done to simultaneously incorporate these mechanisms in the lattice Boltzmann model for simulating gas flow through porous media. This paper presents a lattice Boltzmann model for gas flow through porous media with a consideration of these effects. The apparent permeability and porosity are calculated based on the intrinsic permeability, intrinsic porosity, permeability modulus, porosity sensitivity exponent, and pressure. Gas flow in a two-dimensional channel filled with a homogeneous porous medium is simulated to validate the present model. Simulation results reveal that gas slippage can enhance the flow rate in tight porous media, while stress sensitivity of permeability and porosity reduces the flow rate. The simulation results of gas flow in a porous medium with different mineral components show that the gas slippage and stress sensitivity of permeability and porosity not only affect the global velocity magnitude, but also have an effect on the flow field. In addition, gas flow in a porous medium with fractures is also investigated. It is found that the fractures along the pressure-gradient direction significantly enhance the total flow rate, while the fractures perpendicular to the pressure-gradient direction have little effect on the global permeability of the porous medium. For the porous medium without fractures, the gas-slippage effect is a major influence factor on the global permeability, especially under low pressure; for the porous medium with fractures, the stress-sensitivity effect plays a more important role in gas flow.

10.
J Diabetes Metab Disord ; 23(1): 353-364, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38932858

RESUMEN

Purpose: Microgravity, characterized by gravity levels of 10-3-10-6g, has been found to significantly impair various physiological systems in astronauts, including cardiovascular function, bone density, and metabolism. With the recent surge in human spaceflight, understanding the impact of microgravity on biological health has become paramount. Methods: A comprehensive literature search was performed using the PubMed database to identify relevant publications pertaining to the interplay between gut microbiome, microgravity, space environment, and metabolic diseases. Results: This comprehensive review primarily focuses on the progress made in investigating the gut microbiome and its association with metabolic diseases under microgravity conditions. Microgravity induces notable alterations in the composition, diversity, and functionality of the gut microbiome. These changes hold direct implications for metabolic disorders such as cardiovascular disease (CVD), bone metabolism disorders, energy metabolism dysregulation, liver dysfunction, and complications during pregnancy. Conclusion: This novel perspective is crucial for preparing for deep space exploration and interstellar migration, where understanding the complex interplay between the gut microbiome and metabolic health becomes indispensable.

11.
Talanta ; 278: 126502, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38968653

RESUMEN

Antimony (Sb) pollution has raised increasing public concerns and its rapid on-site screening is central for the risk assessment. Herein, we proposed two gel-based methods based on colorimetric diffusive equilibrium in thin films (DET) and surface-enhanced Raman scattering (SERS), for two-dimensional imaging and sensitive detection of Sb(III) by revisiting the phenylfluorone (PhF) complexation reaction. PhF was well dispersed in the polyvinyl alcohol (PVA) hydrogel and reacted with Sb(III) in the DET gel to form a strong PhF-Sb(III) complex. The distribution of Sb(III) was easily visualized at a submillimeter resolution using computer imaging densitometry, with a detection limit (LOD) of ∼100 nmol L-1. Field application in the Sb mine area reveals limited dissolved Sb(III) penetrating the redox barrier below the sediment-water interface by 20 mm in rivers and tailing pond sediments. To improve the detection sensitivity and apply the principle to trace Sb quantification, a SERS platform was established by anchoring PhF on the hydrogel-stabilized Ag nanoparticles via C-O-Ag bonding to specifically detect Raman-inactive Sb(III). Benefiting from the high SERS activity of PhF and enrichment ability of hydrogel, Sb(III) was quantified with a LOD of 1.2-10.7 nmol L-1 depending on the sample volume. The coexisting ions at a 100-fold higher concentration than Sb(III) resulted in only 3.3-10.4 % variation in SERS intensity, indicating a negligible interference on the SERS platform. The platform exhibited a RSD of 6.6-13.1 % and acceptable recoveries for various environmental matrices, highlighting its promise in on-site application.

12.
J Int Med Res ; 52(6): 3000605241258160, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38867514

RESUMEN

OBJECTIVE: To assess the diagnostic value of C-reactive protein (CRP) and procalcitonin (PCT) for anastomotic leakage (AL) following colorectal surgery. METHODS: We retrospectively analyzed data for patients who underwent colorectal surgery at our hospital between November 2019 and December 2023. CRP and PCT were measured postoperatively to compare patients with/without AL, and changes were compared between low- and high-risk groups. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic accuracy of CRP and PCT to identify AL in high-risk patients. RESULTS: Mean CRP was 142.53 mg/L and 189.57 mg/L in the low- and high-risk groups, respectively, on postoperative day (POD)3. On POD2, mean PCT was 2.75 ng/mL and 8.16 ng/mL in low- and high-risk patients, respectively; values on POD3 were 3.53 ng/mL and 14.86 ng/mL, respectively. The areas under the curve (AUC) for CRP and PCT on POD3 were 0.71 and 0.78, respectively (CRP cut-off: 235.64 mg/L; sensitivity: 96%; specificity: 89.42% vs PCT cut-off: 3.94 ng/mL; sensitivity: 86%; specificity: 93.56%; AUC: 0.78). The AUC, sensitivity, and specificity for the combined diagnostic ability of CRP and PCT on POD3 were 0.92, 90%, and 100%, respectively (cut-off: 0.44). CONCLUSIONS: Combining PCT and CRP on POD3 enhances the diagnostic accuracy for AL.


Asunto(s)
Fuga Anastomótica , Biomarcadores , Proteína C-Reactiva , Polipéptido alfa Relacionado con Calcitonina , Curva ROC , Humanos , Fuga Anastomótica/sangre , Fuga Anastomótica/diagnóstico , Fuga Anastomótica/etiología , Polipéptido alfa Relacionado con Calcitonina/sangre , Proteína C-Reactiva/análisis , Proteína C-Reactiva/metabolismo , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Biomarcadores/sangre , Factores de Riesgo , Cirugía Colorrectal/efectos adversos , Adulto
13.
Stem Cells Transl Med ; 13(7): 648-660, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38736295

RESUMEN

Cholestatic liver disease (CLD) is a severe disease, which can progress to liver cirrhosis, even liver cancer. Hepatic stellate cells (HSCs) activation plays a crucial role in CLD development. Bone mesenchymal stem cells (BMSCs) treatment was demonstrated to be beneficial in liver diseases. However, the therapeutic effect and mechanism of BMSCs on CLD are poorly known. In the present study, we investigated the therapeutic effects and underlying mechanisms of BMSCs transplantation in mouse models of bile duct ligation-induced cholestatic liver fibrosis (CLF). The results revealed that BMSCs significantly improved liver function and reduced the formation of fibrosis after portal vein transplantation. Mechanistically, after coculturing BMSCs and HSCs, we identified that BMSCs alleviated starvation-induced HSCs activation. Further, BMSCs inhibited HSCs activation by decreasing autophagy, and PI3K/AKT/mTOR pathway was involved in the regulation. More importantly, ULK1 is identified as the main autophagy-related gene regulated by BMSCs in HSCs autophagy. Overexpression of ULK1 reversed the suppression of HSCs autophagy by BMSCs. Collectively, our results provide a theoretical basis for BMSCs targeting ULK1 to attenuate HSCs autophagy and activation and suggest that BMSCs or ULK1 may be an alternative therapeutic approach/target for the treatment of CLF.


Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Cirrosis Hepática , Células Madre Mesenquimatosas , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Serina-Treonina Quinasas TOR , Animales , Autofagia/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Células Madre Mesenquimatosas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratones , Fosfatidilinositol 3-Quinasas/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/terapia , Cirrosis Hepática/patología , Transducción de Señal , Trasplante de Células Madre Mesenquimatosas/métodos , Masculino , Ratones Endogámicos C57BL , Células Estrelladas Hepáticas/metabolismo , Colestasis/metabolismo , Colestasis/patología
14.
RSC Adv ; 14(2): 863-871, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38174275

RESUMEN

Photo-responsive nanoporous polymer films (AZOF-R(NC6)) have been developed by a template method based on a hydrogen-bonding supramolecular liquid crystal (LC) and a light-sensitive azobenzene LC crosslinker in this work. Anionic nanopores were obtained after the removal of template NC6 using KOH solution. The AZOF-R(NC6) demonstrates charge-selective dye adsorption and the maximum adsorption capacity for Rh6G is 504.6 mg g-1. The AZOF-R(NC6) film without UV light treatment shows a 32% higher adsorption capacity for Rh6G than the AZOF-R(NC6) film treated with UV light within the initial 10 min. In addition, UV light can trigger the release of the adsorbed dye from the polymer film due to the pore size change arising from the trans-cis isomerization. Besides, the used polymer film can be effectively regenerated using a HCl solution. Such functional polymer films with highly ordered nanopores and photo-responsive properties hold great promise in selective adsorption and mass separations.

15.
ScientificWorldJournal ; 2013: 458341, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23878524

RESUMEN

Recurrence interval of large earthquake on an active fault zone is an important parameter in assessing seismic hazard. The 2008 Wenchuan earthquake (Mw 7.9) occurred on the central Longmen Shan fault zone and ruptured the Yingxiu-Beichuan fault (YBF) and the Guanxian-Jiangyou fault (GJF). However, there is a considerable discrepancy among recurrence intervals of large earthquake in preseismic and postseismic estimates based on slip rate and paleoseismologic results. Post-seismic trenches showed that the central Longmen Shan fault zone probably undertakes an event similar to the 2008 quake, suggesting a characteristic earthquake model. In this paper, we use the published seismogenic model of the 2008 earthquake based on Global Positioning System (GPS) and Interferometric Synthetic Aperture Radar (InSAR) data and construct a characteristic seismic moment accumulation/release model to estimate recurrence interval of large earthquakes on the central Longmen Shan fault zone. Our results show that the seismogenic zone accommodates a moment rate of (2.7 ± 0.3) × 10¹7 N m/yr, and a recurrence interval of 3900 ± 400 yrs is necessary for accumulation of strain energy equivalent to the 2008 earthquake. This study provides a preferred interval estimation of large earthquakes for seismic hazard analysis in the Longmen Shan region.


Asunto(s)
Terremotos/clasificación , Terremotos/estadística & datos numéricos , Modelos Estadísticos , Vibración , China , Simulación por Computador
16.
Artículo en Inglés | MEDLINE | ID: mdl-36833613

RESUMEN

Active fault detection has an important significance for seismic disaster prevention and mitigation in urban areas. The high-density station arrays have the potential to provide a microtremor survey solution for shallow seismic investigations. However, the resolution limitation of the nodal seismometer and small-scale lateral velocity being inhomogeneous hinder their application in near-surface active fault exploration. Distributed acoustic sensing (DAS) has been developed rapidly in the past few years; it takes an optical fiber as the sensing medium and signal transmission medium, which can continuously detect vibration over long distances with high spatial resolution and low cost. This paper tried to address the issue of near-surface active fault exploration by using DAS. We selected a normal fault in the southern Datong basin, a graben basin in the Shanxi rift system in north China, to carry out the research. Microtremor surveys across the possible range of the active fault were conducted using DAS and nodal seismometers, so as to obtain a shallow shear wave velocity model. Meanwhile, we applied a Brillouin optical time domain reflectometer (BOTDR) and distributed temperature sensing (DTS) to monitor the real-time fluctuation of ground temperature and strain. Our results show that the resolution of the deep structures of the fault via the microtremor survey based on DAS is lower than that via the seismic reflection; whereas, their fault location is consistent, and the near-surface structure of the fault can be traced in the DAS results. In addition, both the BOTDR and DTS results indicate an apparent consistent change in ground temperature and strain across the fault determined by the DAS result, and the combination of surface monitoring and underground exploration will help to accurately avoid active faults and seismic potential assessment in urban areas.


Asunto(s)
Desastres , China , Encuestas y Cuestionarios , Temperatura , Factor de Crecimiento Transformador beta , Acústica
17.
Heliyon ; 9(1): e12742, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36685453

RESUMEN

Background: Percutaneous puncture is an important means of tumor diagnosis and treatment. At present, most puncture operations are still based on imaging location and clinical experience, and quantitative and accurate targeted puncture cannot be achieved. How to improve the accuracy of percutaneous tumor puncture, avoid errors to the greatest extent, reduce the occurrence of complications, and improve the overall clinical diagnosis and treatment quality and curative effect, are scientific problems worthy of further study. Method: In the present study, mathematical modeling was first used to construct the tumor puncture path, determine the needle entry angle, and define the relevant limited parameters and the substitution formula. Secondly, relevant parameters were extracted from CT and other imaging data and substituted into formulas, the deviation angle and puncture path were determined, and the personalized tumor puncture scheme was carried out. Third, targeted puncture was precisely implemented under the guidance of B-ultrasound. Compared with the traditional empirical puncture, our model improved the accuracy, decreased the puncture time, and reduced the pain of diagnosis and treatment for patients. Results: A tumor-targeted puncture model was established based on mathematical theory and imaging data. By extracting clinical data, such as tumor radius, projection distance of tumor center and projection distance from puncture point to body surface, the optimal puncture deviation angle was modeled and calculated and a personalized puncture scheme was established. Compared with the conventional method, our model markedly increased the puncture accuracy rate by ∼30%. The puncture number was decreased by ∼50% using our model. Furthermore, our model shortened the operation time by 20% to ease pain of patients and guarantee greater security for patients. Doctor satisfaction and patient discomfort scores were examined. Our model improved doctor satisfaction by ∼20% and reduced subjective discomfort of patients by ∼25%. These data revealed that the model could markedly improve the accuracy and efficiency of puncture, clinical efficacy and accuracy of tumor diagnosis. Additionally, the confidence of doctors in the operation was greatly enhanced and patient discomfort was greatly reduced. Conclusion: The present study analyzed in detail how to find the best puncture path using a mathematical model. Based on the mathematical model of cognitive fusion puncture, combined with clinical personalized data and mathematical calculation analysis, accurate puncture was effectively realized. It not only greatly improved the effectiveness of puncture, but also ensured the safety of clinical patients and reduced injury, which means it may be worthy of clinical application.

18.
Materials (Basel) ; 16(12)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37374406

RESUMEN

Cement is always used in underground construction to reinforce and improve soft clay, resulting in the formation of a cemented soil-concrete interface. It is of great importance to study interface shear strength and failure mechanisms. So, in order to figure out the failure mechanism and characteristics of a cemented soil-concrete interface, a series of large-scale shear tests of a cemented soil-concrete interface, and corresponding unconfined compressive tests and direct shear tests of cemented soil, were carried out specifically under different impact factors. A kind of bounding strength was observed during large-scale interface shearing. Resultantly, three stages of the shear failure process of the cemented soil-concrete interface are proposed, and bonding strength, peak (shear) strength and residual strength are pointed out, respectively, in interface shear stress-strain development. Based on the analysis results of the impact factors, the shear strength of the cemented soil-concrete interface increases with age, the cement mixing ratio and normal stress, and decreases with the water-cement ratio. Additionally, the interface shear strength grows much more rapidly after 14 d to 28 d compared to the early stage (1~7 d). Additionally, the shear strength of the cemented soil-concrete interface is positively related to unconfined compressive strength and shear strength. However, the trends of the bonding strength and unconfined compressive strength or shear strength are much closer than those of the peak and residual strength. This is considered to be related to the cementation of cement hydration products and probably the particle arrangement of the interface. Particularly, the cemented soil-concrete interface shear strength is always smaller than the cemented soil's own shear strength at any age.

19.
Artículo en Inglés | MEDLINE | ID: mdl-37672374

RESUMEN

In recent years, object localization and detection methods in remote sensing images (RSIs) have received increasing attention due to their broad applications. However, most previous fully supervised methods require a large number of time-consuming and labor-intensive instance-level annotations. Compared with those fully supervised methods, weakly supervised object localization (WSOL) aims to recognize object instances using only image-level labels, which greatly saves the labeling costs of RSIs. In this article, we propose a self-directed weakly supervised strategy (SD-WSS) to perform WSOL in RSIs. To specify, we fully exploit and enhance the spatial feature extraction capability of the RSIs' classification model to accurately localize the objects of interest. To alleviate the serious discriminative region problem exhibited by previous WSOL methods, the spatial location information implicit in the classification model is carefully extracted by GradCAM ++ to guide the learning procedure. Furthermore, to eliminate the interference from complex backgrounds of RSIs, we design a novel self-directed loss to make the model optimize itself and explicitly tell it where to look. Finally, we review and annotate the existing remote sensing scene classification dataset and create two new WSOL benchmarks in RSIs, named C45V2 and PN2. We conduct extensive experiments to evaluate the proposed method and six mainstream WSOL methods with three backbones on C45V2 and PN2. The results demonstrate that our proposed method achieves better performance when compared with state-of-the-arts.

20.
Campbell Syst Rev ; 19(1): e1308, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36911856

RESUMEN

This is the protocol for a Campbell evidence and gap map. The objective of the map is to map available systematic reviews on the effectiveness of treatments for depressive disorders among adults. Specifically, this EGM includes studies on the effectiveness of treatments across a range of outcome domains.

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