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1.
Risk Anal ; 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39128862

RESUMEN

Urban flooding is among the costliest natural disasters worldwide. Timely and effective rescue path planning is crucial for minimizing loss of life and property. However, current research on path planning often fails to adequately consider the need to assess area risk uncertainties and bypass complex obstacles in flood rescue scenarios, presenting significant challenges for developing optimal rescue paths. This study proposes a deep reinforcement learning (RL) algorithm incorporating four main mechanisms to address these issues. Dual-priority experience replays and backtrack punishment mechanisms enhance the precise estimation of area risks. Concurrently, random noisy networks and dynamic exploration techniques encourage the agent to explore unknown areas in the environment, thereby improving sampling and optimizing strategies for bypassing complex obstacles. The study constructed multiple grid simulation scenarios based on real-world rescue operations in major urban flood disasters. These scenarios included uncertain risk values for all passable areas and an increased presence of complex elements, such as narrow passages, C-shaped barriers, and jagged paths, significantly raising the challenge of path planning. The comparative analysis demonstrated that only the proposed algorithm could bypass all obstacles and plan the optimal rescue path across nine scenarios. This research advances the theoretical progress for urban flood rescue path planning by extending the scale of scenarios to unprecedented levels. It also develops RL mechanisms adaptable to various extremely complex obstacles in path planning. Additionally, it provides methodological insights into artificial intelligence to enhance real-world risk management.

2.
Environ Res ; 262(Pt 1): 119856, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39197485

RESUMEN

Artificial biomanufacturing has been developed as a promising biotechnology for water pollution control. Effective bioimmobilization techniques are limited in application because of low productivity and the difficulty in achieving both mechanical strength and biocompatibility. Bioprinting technology, using biomaterials as bioink to enable the rapid on-demand production of bioactive structures, opens a new path for bioimmobilization. In this study, mimicking extracellular polysaccharide and protein of aerobic granular sludge (AGS), sodium alginate (SA) and silk fibroin methacryloyl (SilMA) were developed as the dual-component bioink with a suitable viscosity for bioprinting hydrogel. Interpenetrating network (IPN) hydrogel beads were manufactured using 1.5% (w/v) SA combined with 20% (w/v) SilMA through physical and covalent crosslinking, which exhibited excellent structural stability and bioactivity. The addition of SilMA provided a solution to the poor mechanical stability of SA-Ca hydrogels limited by Ca2+-Na+ ionic exchange. The unique structure of SilMA contributed to the reduction of hydrogel swelling as well as the prevention of SA loss. IPN hydrogels showed a swelling rate of less than 20% compared to the high swelling rate of more than 60% for SA hydrogels. On the other hand, SA controlled the hardening induced by excessive self-assembly of SilMA and improved mass transport in SilMA hydrogels. Compared to IPN hydrogels, SilMA hydrogels experienced a 15% volumetric shrinkage and exhibited a low water content of 92%. Sonication pretreatment of the dual-component bioink not only increased the intermolecular chain entanglement to form IPN, but also led to ß-sheet content in SiMA reaching 46%-48%, which resulted in the formation of stable IPN hydrogels dominated entirely by physical crosslinking. Satisfactory proliferation and viability were achieved for the encapsulated bacteria in IPN hydrogels (µmax 1.49-2.18 d-1). Further, the IPN biohydrogels could maintain structural stability as well as achieve pollutant removal for treating synthetic wastewater with high Na+ concentration of 300 mg/L. The novel SA/SilMA hydrogel bioprinting strategy established in this study offers a new direction for bioimmobilization in water pollution control and other environmental applications.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 823-828, 2024 Aug 15.
Artículo en Chino | MEDLINE | ID: mdl-39148386

RESUMEN

OBJECTIVES: To study the clinical characteristics of children with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: A retrospective analysis was conducted on the clinical data of 25 children diagnosed with AAV at the Second Xiangya Hospital of Central South University from January 2010 to June 2022. RESULTS: Among the AAV children, there were 5 males and 20 females, with a median age of onset of 11.0 years. Involvement of the urinary system was seen in 18 cases (72%); respiratory system involvement in 10 cases (40%); skin involvement in 6 cases (24%); eye, ear, and nose involvement in 5 cases (20%); joint involvement in 4 cases (16%); digestive system involvement in 2 cases (8%). Eleven cases underwent kidney biopsy, with 5 cases (46%) showing focal type, 2 cases (18%) showing crescentic type, 2 cases (18%) showing mixed type, and 2 cases (18%) showing sclerotic type. Immune complex deposits were present in 5 cases (45%). Seven cases reached chronic kidney disease (CKD) stage V, with 2 cases resulting in death. Two cases underwent kidney transplantation. At the end of the follow-up period, 2 cases were at CKD stage II, and 1 case was at CKD stage III. Of the 16 cases of microscopic polyangiitis (MPA) group, 13 (81%) involved the urinary system. Of the 9 cases of granulomatosis with polyangiitis (GPA), 6 cases (66%) had sinusitis. Serum creatinine and uric acid levels were higher in the MPA group than in the GPA group (P<0.05), while red blood cell count and glomerular filtration rate were lower in the MPA group (P<0.05). CONCLUSIONS: AAV is more common in school-age female children, with MPA being the most common clinical subtype. The onset of AAV in children is mainly characterized by renal involvement, followed by respiratory system involvement. The renal pathology often presents as focal type with possible immune complex deposits. Children with MPA often have renal involvement, while those with GPA commonly have sinusitis. The prognosis of children with AAV is poor, often accompanied by renal insufficiency.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Humanos , Femenino , Masculino , Niño , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Estudios Retrospectivos , Adolescente , Preescolar , Insuficiencia Renal Crónica/etiología
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(8): 835-839, 2024 Aug 15.
Artículo en Chino | MEDLINE | ID: mdl-39148388

RESUMEN

OBJECTIVES: To study the correlation of anti-C1q antibodies with active systemic lupus erythematosus (SLE) and lupus nephritis (LN) in children, as well as their diagnostic value for active SLE and LN. METHODS: A retrospective selection of 90 hospitalized children with SLE at the Children's Medical Center of Second Xiangya Hospital, Central South University from January 2016 to March 2019 as the SLE group, all of whom were tested for anti-C1q antibodies. A control group was formed by collecting 70 hospitalized children with other autoimmune diseases (OAD) during the same period. The differences in anti-C1q antibody levels were compared between two groups.The correlation of anti-C1q antibodies with various indicators of SLE and LN was analyzed, and the diagnostic value of anti-C1q in SLE and LN was evaluated. RESULTS: The serum levels of anti-C1q antibodies in the SLE group were higher than those in the OAD group (P<0.05). The SLE disease activity index score was positively correlated with anti-C1q antibodies (rs=0.371, P<0.001) and positively correlated with anti-double-stranded DNA antibodies (rs=0.370, P<0.001). The sensitivity and specificity of anti-C1q antibodies for diagnosing active SLE were 89.90% and 53.90%, respectively, with an area under the curve of 0.720 (P<0.05) and a critical value of 5.45 U/mL. The sensitivity and specificity of anti-C1q antibody levels for diagnosing active LN were 58.50% and 85.00%, respectively, with an area under the curve of 0.675 (P<0.05) and a critical value of 22.05 U/mL. CONCLUSIONS: Anti-C1q antibodies can serve as non-invasive biomarkers for evaluating the activity of SLE or predicting the activity of LN in children.


Asunto(s)
Complemento C1q , Lupus Eritematoso Sistémico , Nefritis Lúpica , Humanos , Complemento C1q/inmunología , Nefritis Lúpica/inmunología , Nefritis Lúpica/sangre , Femenino , Niño , Masculino , Lupus Eritematoso Sistémico/inmunología , Estudios Retrospectivos , Adolescente , Autoanticuerpos/sangre , Preescolar , Anticuerpos Antinucleares/sangre , Anticuerpos Antinucleares/inmunología
5.
Water Res ; 263: 122173, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39111213

RESUMEN

Wastewater treatment plants face significant challenges in transitioning from energy-intensive systems to carbon-neutral, energy-saving systems, and a large amount of chemical energy in wastewater remains untapped. Iron is widely used in modern wastewater treatment. Research shows that leveraging the coupled redox relationship of iron and carbon can redirect this energy (in the form of carbon) towards resource utilization. Therefore, re-examining the application of iron in existing wastewater carbon processes is particularly important. In this review, we investigate the latest research progress on iron for wastewater carbon flow restructuring. During the iron-based chemically enhanced primary treatment (CEPT) process, organic carbon is captured into sludge and its bioavailability is enhanced through iron-based advanced oxidation processes (AOP) pretreatment, further being recovered or upgraded to value-added products in anaerobic biological processes. We discuss the roles and mechanisms of iron in CEPT, AOP, anaerobic biological processes, and biorefining in driving organic carbon conversion. The dosage of iron, as a critical parameter, significantly affects the recovery and utilization of sludge carbon resources, particularly by promoting effective electron transfer. We propose a pathway for beneficial conversion of wastewater organic carbon driven by iron and analyze the benefits of the main products in detail. Through this review, we hope to provide new insights into the application of iron chemicals and current wastewater treatment models.


Asunto(s)
Carbono , Hierro , Eliminación de Residuos Líquidos , Aguas Residuales , Hierro/química , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Oxidación-Reducción , Aguas del Alcantarillado/química
6.
Artículo en Inglés | MEDLINE | ID: mdl-39119898

RESUMEN

OBJECTIVES: Mechanisms of non-typhoidal Salmonella (NTS) resistance to azithromycin have rarely been reported. Here we investigate the epidemiology and genetic features of 10 azithromycin-resistant NTS isolates. METHODS: A total of 457 NTS isolates were collected from a tertiary hospital in Guangzhou. We performed antimicrobial susceptibility tests, conjugation experiments, efflux pump expression tests, whole-genome sequencing and bioinformatics analysis to conduct the study. RESULTS: The results showed that 10 NTS isolates (2.8%) were resistant to azithromycin with minimum inhibitory concentration values ranging from 128 to 512 mg/L and exhibited multidrug resistance. The phylogenetic tree revealed that 5 S. London isolates (AR1-AR5) recognized at different times and departments were closely related [3-74 single-nucleotide polymorphisms (SNPs)] and 2 S. Typhimurium isolates (AR7 and AR8) were clones (<3 SNPs) at 3-month intervals. The azithromycin resistance was conferred by mph(A) gene found on different plasmids, including IncFIB, IncHI2, InFII, IncC and IncI plasmids. Among them, IncFIB, InFII and IncHI2 plasmids carried different IS26-class 1 integron (intI1) arrangement patterns that mediated multidrug resistance transmission. Conjugative IncC plasmid encoded resistance to ciprofloxacin, ceftriaxone and azithromycin. Furthermore, phylogenetic analysis demonstrated that mph(A)-positive plasmids closely related to 10 plasmids in this study were mainly discovered from NTS, Escherichia coli, Klebsiella pneumonia and Enterobacter hormaechei. The genetic environment of mph(A) in 10 NTS isolates was IS26-mph(A)-mrx(A)-mphR(A)-IS6100/IS26 that co-arranged with intI1 harbour multidrug-resistant (MDR) gene cassettes on diverse plasmids. CONCLUSIONS: These findings highlighted that the dissemination of these plasmids carrying mph(A) and various intI1 MDR gene cassettes would seriously restrict the availability of essential antimicrobial agents for treating NTS infections.

7.
J Cell Biol ; 223(9)2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-38990714

RESUMEN

Dermal fibroblasts deposit type I collagen, the dominant extracellular matrix molecule found in skin, during early postnatal development. Coincident with this biosynthetic program, fibroblasts proteolytically remodel pericellular collagen fibrils by mobilizing the membrane-anchored matrix metalloproteinase, Mmp14. Unexpectedly, dermal fibroblasts in Mmp14-/- mice commit to a large-scale apoptotic program that leaves skin tissues replete with dying cells. A requirement for Mmp14 in dermal fibroblast survival is recapitulated in vitro when cells are embedded within, but not cultured atop, three-dimensional hydrogels of crosslinked type I collagen. In the absence of Mmp14-dependent pericellular proteolysis, dermal fibroblasts fail to trigger ß1 integrin activation and instead actuate a TGF-ß1/phospho-JNK stress response that leads to apoptotic cell death in vitro as well as in vivo. Taken together, these studies identify Mmp14 as a requisite cell survival factor that maintains dermal fibroblast viability in postnatal dermal tissues.


Asunto(s)
Apoptosis , Supervivencia Celular , Fibroblastos , Metaloproteinasa 14 de la Matriz , Animales , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 14 de la Matriz/genética , Fibroblastos/metabolismo , Ratones , Ratones Noqueados , Colágeno Tipo I/metabolismo , Colágeno Tipo I/genética , Integrina beta1/metabolismo , Integrina beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Dermis/metabolismo , Dermis/citología , Células Cultivadas , Matriz Extracelular/metabolismo , Ratones Endogámicos C57BL , Piel/metabolismo
8.
Nat Prod Res ; : 1-6, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38980006

RESUMEN

A new polyketide, mauritone A (1) with six known polyketides curvulone B (2), curvularin (3), 12-oxocurvularin (4), (10E,15S)-10,11-dehydrocurvularin (5), (11R,15S)-11-hydroxycurvularin (6), and (11S,15S)-11-hydroxycurvularin (7) were isolated from the fungal-bacterial symbiont Aspergillus spelaeus GXIMD 04541/Sphingomonas echinoides GXIMD 04532 derived from Mauritia arabica. Their structures were elucidated by extensive spectral analysis. All compounds (1-7) were evaluated for their anti-inflammatory effects. The inhibitory effects of 4, 5, and 7 on nitric oxide (NO) production were found to be significant, with IC50 values of 5.5 ± 0.26, 2.0 ± 0.31, and 8.3 ± 0.62 µM, respectively, surpassing that of the positive control quercetin (10.6 ± 0.64 µM). Compounds 3 and 6 exhibited moderate inhibition of NO, with IC50 values of 18.6 ± 0.53 and 12.7 ± 0.45 µM, respectively.

9.
Environ Sci Technol ; 58(27): 12225-12236, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38885124

RESUMEN

Nanoscale zerovalent iron synthesized using borohydride (B-NZVI) has been widely applied in environmental remediation in recent decades. However, the contribution of boron in enhancing the inherent reactivity of B-NZVI and its effectiveness in removing hexavalent chromium [Cr(VI)] have not been well recognized and quantified. To the best of our knowledge, herein, a core-shell structure of B-NZVI featuring an Fe-B alloy shell beneath the iron oxide shell is demonstrated for the first time. Alloyed boron can reduce H+, contributing to more than 35.6% of H2 generation during acid digestion of B-NZVIs. In addition, alloyed B provides electrons for Fe3+ reduction during Cr(VI) removal, preventing in situ passivation of the reactive particle surface. Meanwhile, the amorphous oxide shell of B-NZVI exhibits an increased defect density, promoting the release of Fe2+ outside the shell to reduce Cr(VI), forming layer-structured precipitates and intense Fe-O bonds. Consequently, the surface-area-normalized capacity and surface reaction rate of B-NZVI are 6.5 and 6.9 times higher than those of crystalline NZVI, respectively. This study reveals the importance of alloyed B in Cr(VI) removal using B-NZVI and presents a comprehensive approach for investigating electron pathways and mechanisms involved in B-NZVIs for contaminant removal.


Asunto(s)
Borohidruros , Boro , Hierro , Hierro/química , Borohidruros/química , Boro/química , Cromo/química , Electrones , Aleaciones/química
10.
Mol Neurobiol ; 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850348

RESUMEN

Dysbiosis of the gut microbiota is closely associated with neurodegenerative diseases, including Huntington's disease (HD). Gut microbiome-derived metabolites are key factors in host-microbiome interactions. This study aimed to investigate the crucial gut microbiome and metabolites in HD and their correlations. Fecal and serum samples from 11 to 26 patients with HD, respectively, and 16 and 23 healthy controls, respectively, were collected. The fecal samples were used for shotgun metagenomics while the serum samples for metabolomics analysis. Integrated analysis of the metagenomics and metabolomics data was also conducted. Firmicutes, Bacteroidota, Proteobacteria, Uroviricota, Actinobacteria, and Verrucomicrobia were the dominant phyla. At the genus level, the presence of Bacteroides, Faecalibacterium, Parabacteroides, Alistipes, Dialister, and Christensenella was higher in HD patients, while the abundance of Lachnospira, Roseburia, Clostridium, Ruminococcus, Blautia, Butyricicoccus, Agathobaculum, Phocaeicola, Coprococcus, and Fusicatenibacter decreased. A total of 244 differential metabolites were identified and found to be enriched in the glycerophospholipid, nucleotide, biotin, galactose, and alpha-linolenic acid metabolic pathways. The AUC value from the integrated analysis (1) was higher than that from the analysis of the gut microbiota (0.8632). No significant differences were found in the ACE, Simpson, Shannon, Sobs, and Chao indexes between HD patients and controls. Our study determined crucial functional gut microbiota and potential biomarkers associated with HD pathogenesis, providing new insights into the role of the gut microbiota-brain axis in HD occurrence and development.

11.
Water Res ; 258: 121785, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38761595

RESUMEN

The city-river-reservoir system is an important system for safeguarding drinking water. Phthalic acid esters (PAEs) are emerging contaminants in drinking water sources that are gaining attention, and they could pose risks to human health and aquatic organisms. In this study, field studies that lasted four years were conducted to analyze the concentrations, spatial-temporal distribution, and removal effects of six PAEs. The total concentrations of the Σ6PAEs in the water and sediment samples were 0.2-7.4 µg L-1 (mean: 1.3 µg L-1) and 9.2-9594.1 ng g-1 (mean: 847.5 ng g-1), respectively. Di-n-butyl phthalate (DBP) and, bis(2-ethylhexyl) phthalate (DEHP) were the predominant congeners, accounting for 57.2 % in the water samples and 94.1 % in the sediment samples. The urban area contributed 72 % of the PAEs in the system. A significant removal effect of PAEs was observed in the wetland, with a removal rate of 40.2 %. The partitioning of PAEs between the water and sediment was attributed to the removal of dimethyl phthalate and diethyl phthalate that occurred during the water phase, while the removal of DBP and DEHP primarily occurred during the sediment phase. The ecological risk calculation based on the sensitivity distribution model indicated that DBP (HQwater = 0.19, HQsediment = 0.46) and DEHP (HQwater = 0.20, HQsediment = 0.13) possessed moderate risks according to some water and sediment samples. The ecological projects were verified to be effective engineering strategies to reduce ecological risk in the drinking water source.


Asunto(s)
Ésteres , Ácidos Ftálicos , Ríos , Contaminantes Químicos del Agua , Ácidos Ftálicos/análisis , Contaminantes Químicos del Agua/análisis , Ríos/química , Ésteres/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química
12.
Aquat Toxicol ; 272: 106962, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38797068

RESUMEN

Diisobutyl phthalate (DiBP), is widely chemical replacement for Dibutyl phthalate (DBP). Although DBP and DiBP have been detected in surface water worldwide, few studies to date have systematically assessed the risks of DBP and its alternatives to aquatic organisms. The present study compared DBP and DiBP for their individual and joint toxicity as well as thyroid hormone levels in zebrafish embryo. Transcripts of key genes related to the hypothalamic-pituitary-thyroid (HPT) axis were investigated in developing zebrafish larvae by application of real time polymerase chain reaction. The median half-lethal concentrations of DBP and DiBP to zebrafish at 96 h were 0.545 mg L-1 and 1.149 mg L-1, respectively. The joint toxic effect of DBP-DiBP (0.25-0.53 mg L-1) with the same ratio showed a synergistic effect. Thyroid hormones levels increased with exposure to 10 µg L-1 of DBP or 50 µg L-1 of DiBP, and exposure to both compounds significantly increased thyroid gland-specific transcription of thyroglobulin gene (tg), hyronine deiodinase (dio2), and transthyretin (ttr), indicating an adverse effect associated with the HPT axis. Molecular docking results indicated that DBP (-7.10 kcal/M and -7.53 kcal/M) and DiBP (-6.63 kcal/M and -7.42 kcal/M) had the same docking energy with thyroid hormone receptors. Our data facilities an understand of potential harmful effects of DBP and its alternative (DiBP).


Asunto(s)
Dibutil Ftalato , Embrión no Mamífero , Contaminantes Químicos del Agua , Pez Cebra , Animales , Pez Cebra/genética , Dibutil Ftalato/toxicidad , Dibutil Ftalato/análogos & derivados , Contaminantes Químicos del Agua/toxicidad , Embrión no Mamífero/efectos de los fármacos , Ácidos Ftálicos/toxicidad , Hormonas Tiroideas/metabolismo , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Larva/genética , Glándula Tiroides/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos
13.
Int Urogynecol J ; 35(6): 1163-1170, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38695902

RESUMEN

INTRODUCTION AND HYPOTHESIS: The potential predictors of pelvic floor reconstruction surgery hypothermia remain unclear. This prospective cohort study was aimed at identifying these predictors and evaluating the outcomes associated with perioperative hypothermia. METHODS: Elderly patients undergoing pelvic floor reconstruction surgery were consecutively enrolled from April 2023 to September 2023. Perioperative temperature was measured at preoperative (T1), every 15 min after the start of anesthesia (T2), and 15 min postoperative (T3) using a temperature probe. Perioperative hypothermia was defined as a core temperature below 36°C at any point during the procedure. Multivariate logistic regression analysis was conducted to determine factors associated with perioperative hypothermia. RESULTS: A total of 229 patients were included in the study, with 50.7% experiencing hypothermia. Multivariate analysis revealed that the surgical method involving pelvic floor combined with laparoscopy, preoperative temperature < 36.5°C, anesthesia duration ≥ 120 min, and the high levels of anxiety were significantly associated with perioperative hypothermia. The predictive value of the multivariate model was 0.767 (95% CI, 0.706 to 0.828). CONCLUSIONS: This observational prospective study identified several predictive factors for perioperative hypothermia in elderly patients during pelvic floor reconstruction surgery. Strategies aimed at preventing perioperative hypothermia should target these factors. Further studies are required to assess the effectiveness of these strategies, specifically in elderly patients undergoing pelvic floor reconstruction surgery.


Asunto(s)
Hipotermia , Diafragma Pélvico , Humanos , Hipotermia/etiología , Hipotermia/prevención & control , Anciano , Femenino , Estudios Prospectivos , Procedimientos de Cirugía Plástica/métodos , Procedimientos de Cirugía Plástica/efectos adversos , Periodo Perioperatorio , Factores de Riesgo , Anciano de 80 o más Años , Persona de Mediana Edad , Laparoscopía , Prolapso de Órgano Pélvico/cirugía
14.
J Am Chem Soc ; 146(20): 14267-14277, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38717595

RESUMEN

Converting CO2 to synthetic hydrocarbon fuels is of increasing interest. In light of progress in electrified CO2 to ethylene, we explored routes to dimerize to 1-butene, an olefin that can serve as a building block to ethylene longer-chain alkanes. With goal of selective and active dimerization, we investigate a series of metal-organic frameworks having bimetallic catalytic sites. We find that the tunable pore structure enables optimization of selectivity and that periodic pore channels enhance activity. In a tandem system for the conversion of CO2 to 1-C4H8, wherein the outlet cathodic gas from a CO2-to-C2H4 electrolyzer is fed directly (via a dehumidification stage) into the C2H4 dimerizer, we study the highest-performing MOF found herein: M' = Ru and M″ = Ni in the bimetallic two-dimensional M'2(OAc)4M″(CN)4 MOF. We report a 1-C4H8 production rate of 1.3 mol gcat-1 h-1 and a C2H4 conversion of 97%. From these experimental data, we project an estimated cradle-to-gate carbon intensity of -2.1 kg-CO2e/kg-1-C4H8 when CO2 is supplied from direct air capture and when the required energy is supplied by electricity having the carbon intensity of wind.

15.
JACS Au ; 4(5): 1892-1900, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38818067

RESUMEN

Understanding the nonequilibrium transformation of nanocatalysts under reaction conditions is important because metastable atomic structures may be created during the process, which offers unique activities in reactions. Although reshaping of metal nanoparticles (NPs) under reaction conditions has been widely recognized, the dynamic reshaping process has been less studied at the atomic scale. Here, we develop an atomistic kinetic Monte Carlo model to simulate the complete reshaping process of Pt nanoparticles in a CO environment and reveal the in situ formation of atomic clusters on the NP surface, a new type of active site beyond conventional understanding, boosting the reactivities in the CO oxidation reaction. Interestingly, highly active peninsula and inactive island clusters both form on the (111) facets and interchange in varying states of dynamic equilibrium, which influences the catalytic activities significantly. This study provides new fundamental knowledge of nanocatalysis and new guidance for the rational design of nanocatalysts.

16.
Food Chem X ; 22: 101300, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38571574

RESUMEN

The composition of volatile compounds in beer is crucial to the quality of beer. Herein, we identified 23 volatile compounds, namely, 12 esters, 4 alcohols, 5 acids, and 2 phenols, in nine different beer types using GC-MS. By performing PCA of the data of the flavor compounds, the different beer types were well discriminated. Ethyl caproate, ethyl caprylate, and phenylethyl alcohol were identified as the crucial volatile compounds to discriminate different beers. PLS regression analysis was performed to model and predict the contents of six crucial volatile compounds in the beer samples based on the characteristic wavelength of the FTIR spectrum. The R2 value of each sample in the prediction model was 0.9398-0.9994, and RMSEP was 0.0122-0.7011. The method proposed in this paper has been applied to determine flavor compounds in beer samples with good consistency compared with GC-MS.

17.
Chemosphere ; 354: 141720, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38493999

RESUMEN

The release of organic dyes, such as Rhodamine B (RhB), into industrial wastewater has led to significant issues with color pollution in aquatic environments. Herein, we prepared a cobalt nanoparticles (NPs)-based catalyst with the nitrogen-doped carbon-support (Co@N-C) for effective PMS activation. The Co@N-C/PMS system demonstrated the excellent catalytic activity of Co@N-C for activating PMS, achieving nearly 100% degradation of RhB. Singlet oxygen (1O2) and sulfate radicals (SO4•-) were dominant reactive oxygen species for RhB degradation. Density functional theory (DFT) calculations substantiated that the production of 1O2 commenced with the initial generation of *OH through hydrogen abstraction from PMS, culminating in the direct release of oxygen to form 1O2 (PMS→*OH→O*→1O2). The generation of SO4•- was attributed to electron transfer to PMS from the surface of Co NPs (Co0→Co2+→Co3+) and the C-N shell (Co2+→Co3+). The research findings provided new insights into the development of Co-based heterogeneous catalysis for advanced oxidation of refractory organic pollutants in wastewater treatment.


Asunto(s)
Nanopartículas , Peróxidos , Especies Reactivas de Oxígeno , Carbono , Oxígeno
18.
Endokrynol Pol ; 75(1): 61-70, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38497391

RESUMEN

INTRODUCTION: Gestational diabetes mellitus (GDM) is the most common metabolic disease in pregnancy. However, studies of activating molecule of Beclin1-regulated autophagy (Ambra1) affecting the insulin substrate receptor 1/phosphatidylinositol 3 kinase/protein kinase B (IRS-1/PI3K/Akt) signalling pathway in GDM have not been reported. The aim of the study was to detect the difference of Ambra1 expression in the placenta of normal pregnant women and GDM patients. MATERIAL AND METHODS: An in vitro model of gestational diabetes mellitus was established by inducing HTR8/Svneo cells from human chorionic trophoblast layer with high glucose. The changes of cell morphology were observed by inverted microscope, and the expression levels of Ambra1 gene and protein in model cells were detected. After this, Ambra1 gene was silenced by shRNA transfection, and PI3K inhibitor was added to detect changes in Ambra1, autophagy, and insulin (INS) signalling pathways. RESULTS: The protein expression levels of Ambra1, Bcl-2 interacting protein (Beclin-1), and microtubule-associated proteins 1A/1B light chain 3B (LC3-II) in the placentas of GDM pregnant women were higher than those of normal pregnant women. High glucose induces morphological changes in HTR8/Svneo cells and increases Ambra1 transcription and translation levels. sh-Ambra1 increased survival of HTR8/SvNEO-HG cells and inhibited Ambra1, Beclin1, and LC3-II transcription and translation levels. Also, sh-Ambra1 increased IRS-1/PI3K/Akt protein phosphorylation levels and inhibited the IRS-1/PI3K/Akt signalling pathway and its resulting autophagy. CONCLUSIONS: sh-Ambra1 increased IRS-1/PI3K/Akt protein phosphorylation levels to reduce autophagy in gestational diabetes.


Asunto(s)
Diabetes Gestacional , Femenino , Humanos , Embarazo , Autofagia , Beclina-1 , Diabetes Gestacional/metabolismo , Glucosa/metabolismo , Insulina/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo
19.
J Am Chem Soc ; 146(12): 8641-8649, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38470826

RESUMEN

Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.

20.
Ophthalmol Sci ; 4(2): 100426, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38192683

RESUMEN

Purpose: To assess safety and ocular hypotensive efficacy of VVN539 ophthalmic solution in a first-in-human study. Design: Multicenter, double-masked, randomized, vehicle-controlled, dose-response, parallel-comparison study. Participants: Sixty-eight subjects with ocular hypertension (OHT) or open-angle glaucoma enrolled at 5 private practices. Methods: After washout of ocular hypotensive medications as required, the subjects were randomized to receive either VVN539 ophthalmic solution 0.02%, 0.04%, or vehicle once-daily (QD) in the morning (5 days), once-daily in the evening (6 days) and then twice-daily (6 days). Main Outcome Measures: Comparison of VVNM539 to its vehicle in mean intraocular pressure (IOP) at each diurnal time point (8:00am, 10:00am, and 4:00pm) at visit 4 (day 7), visit 5 (day 14), and visit 6 (day 21). Results: Mean IOP decreased throughout dosing in the active groups to between 18 and 20 mmHg in both active groups, to between 22 to 23 mmHg in the vehicle group. VVN539 0.04% was statistically superior to vehicle at all 9 diurnal time points (QD AM, QD PM, and twice daily, P ≤ 0.0109). VVN539 0.02% was statistically superior to vehicle at only 6 of 9 diurnal time points (selected QD times and twice daily). The most common ocular treatment-emergent adverse event was conjunctival hyperemia (11 [47.8%], 10 [4.5%], and 1 [4.3%]), followed by ocular hyperemia (3 [13.0%], 5 [22.7%] and 0), respectively. There were no clinically significant changes of note in visual acuity, biomicroscopy, dilated ophthalmoscopy, blood chemistry, hematology, or cardiovascular measures. Conclusions: In conclusion, the results of this initial phase II study indicate that VVN539 ophthalmic solution showed clinically and statistically significant ocular hypertensive activity and was relatively well tolerated for the treatment of subjects with primary open-angle glaucoma or OHT. Additional studies will be required for a more complete evaluation of the utility of VVN539 ophthalmic solution. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

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