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1.
J Colloid Interface Sci ; 678(Pt C): 300-308, 2025 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-39298982

RESUMO

Although Platinum (Pt)-based alloys have garnered significant interest within the realm of direct methanol fuel cells (DMFCs), there still exists a notable dearth in the exploration of the catalytic behavior of the liquid fuels on well-defined active sites and unavoidable Pt poisoning because of the adsorbed CO species (COads). Here, we propose an electronegativity-induced electronic redistribution strategy to optimize the adsorption of crucial intermediates for the methanol oxidation reaction (MOR) by introducing the Co element to form the PtCo alloys. The optimal PtCo hollow nanospheres (HNSs) exhibit excellent high-quality activity of 3.27 A mgPt-1, which is 11.6 times and 13.1 times higher than that of Pt/C and pure Pt, respectively. The in-situ Fourier transform infrared reflection spectroscopy validates that electron redistribution could weak CO adsorption, and subsequently decrease the CO poisoning adjacent the Pt active sites. Theoretical simulations result show that the introduction of Co optimize surface electronic structure and reduce the d-band center of Pt, thus optimized the adsorption behavior of COads. This study not only employs a straightforward method for the preparation of Pt-based alloys but also delineates a pathway toward designing advanced active sites for MOR via electronegativity-induced electronic redistribution.

2.
Sci Rep ; 14(1): 25460, 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39462011

RESUMO

This paper investigates the fixed-time cluster formation tracking (CFT) problem for networked perturbed robotic systems (NPRSs) under directed graph information interaction, considering parametric uncertainties, external perturbations, and actuator input deadzone. To address this complex problem, a novel hierarchical fixed-time neural adaptive control algorithm is proposed based on a hierarchical fixed-time framework and a neural adaptive control strategy. The objective of this study is to achieve accurate CFT of NPRSs within a fixed time. Specifically, we design a distributed observer algorithm to estimate the states of the virtual leader within a fixed time accurately. By using these observers, a neural adaptive fixed-time controller is developed in the local control layer to ensure rapid and reliable system performance. Through the use of the Lyapunov argument, we derive sufficient conditions on the control parameters to guarantee the fixed-time stability of NPRSs. The theoretical results are eventually validated through numerical simulations, demonstrating the effectiveness and robustness of the proposed approach.

3.
Inorg Chem ; 63(43): 20697-20704, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39425660

RESUMO

High-entropy alloy (HEA) electrocatalysts have exhibited remarkable catalytic performance because of their synergistic interactions among multiple metals. However, the growth mechanism of HEAs remains elusive, primarily due to the constraints imposed by the current synthesis methodologies for HEAs. In this work, an innovative electrodeposition method was developed to fabricate Pt-based nanocomposites (Pt1Bi2Co1Cu1Ni1/CC), comprising HEA nanosheets and carbon cloths (CCs). The reaction system could be effectively monitored by taking samples out from the system during the reaction process, facilitating in-depth insight into the growth mechanism underlying the material formation. In particular, Pt1Bi2Co1Cu1Ni1/CC nanocomposites show superior methanol oxidation reaction (MOR) performance (mass activity up to 5.02 A mgPt-1). Upon structural analysis, the d-band center of Pt1Bi2Co1Cu1Ni1/CC is lower in comparison with that of Pt1Bi2/CC and Pt/CC, demonstrating the formation of a rich-electron structure. Both the uniformity of HEAs and the carbon-supported effect could provide additional active sites. These findings suggest that the strong electronic interaction within HEAs and additional active sites can effectively modulate the catalytic structure of Pt, which benefits the enhanced CO tolerance and MOR performance.

4.
Inorg Chem ; 63(43): 20802-20810, 2024 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-39425657

RESUMO

As a critical component for the oxygen reduction reaction (ORR), platinum (Pt) catalysts exhibit promising catalytic performance in High-temperature-proton exchange membrane fuel cells (HT-PEMFCs). Despite their success, HT-PEMFCs primarily utilize phosphoric acid-doped polybenzimidazole (PA-PBI) as the proton exchange membrane, and the phosphoric acid within the PBI matrix tends to leach onto the Pt-based layers, easily causing toxicity. Herein, we first propose UiO-66@Pt3Co1-T composites with precisely engineered interfacial structures. The UiO-66@Pt3Co1-T exhibits an octahedral porous framework with uniform structural dimensions and even distribution of surface nanoparticles, which demonstrate superior ORR performance compared to commercial Pt/C. The unique structure and morphology of the composites also exhibit a favorable half-wave potential in different concentrations of phosphoric acid electrolyte, regulated by the phosphoric acid adsorption site and intensity.This finding suggests that the incorporation of Co could effectively modulate the Pt d-band center, thereby enhancing the ORR performance. Furthermore, the selective adsorption of phosphoric acid by ZrO2 enables precise control over the phosphoric acid distribution. Notably, the retention of the octahedral framework post high-temperature treatment facilitates the establishment of dual transport pathways for gases and protons, leading to a stable and efficient triple-phase boundary.

5.
Neural Netw ; 180: 106691, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39255635

RESUMO

This research delves into the challenges of achieving secure consensus tracking within multi-agent systems characterized by directed hypergraph topologies, in the face of hybrid deception attacks. The hybrid discrete and continuous deception attacks are targeted at the controller communication channels and the hyperedges, respectively. To overcome these threats, an impulsive control mechanism based on hypergraph theory are introduced, and sufficient conditions are established, under which consensus can be maintained in a mean-square bounded sense, supported by rigorous mathematical proofs. Furthermore, the investigation quantifies the relationship between the mean-square bounded consensus of the multi-agent system and the intensity of the deception attacks, delineating a specific range for this error metric. The robustness and effectiveness of the proposed control method are verified through comprehensive simulation experiments, demonstrating its applicability in varied scenarios influenced by these sophisticated attacks. This study underscores the potential of hypergraph-based strategies in enhancing system resilience against complex hybrid attacks.

6.
Small Methods ; : e2400604, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39279575

RESUMO

2D metal-organic frameworks (2D MOFs) offer promising electrocatalytic potential for urea synthesis, yet the underlying reaction mechanisms and structure-activity relationships remain unclear. Using Cu-BDC as a model, density functional theory (DFT) calculations to elucidate these aspects are conducted. The results reveal a novel coupling mechanism involving *NO─CO and *NO─*ONCO, emphasizing the impact of linker modifications on Cu spin states and charge distribution. Notably, Cu-BDC-NH2 and Cu─BDC─OH emerge as promising catalysts. Additionally, structure-activity relationships through descriptors like d-band center, IE ratio, and L(Cu─O), providing insights for rational catalyst design is established. These findings pave the way for optimized catalysts and sustainable urea production, opening avenues for future research and technological advancements.

7.
J Neurooncol ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225955

RESUMO

OBJECTIVE: This study aimed to develop a predictive model for cerebellar mutism syndrome (CMS) in pediatric patients with posterior fossa tumors, integrating lesion-symptom mapping (LSM) data with clinical factors, and to assess the model's performance. METHODS: A cohort of pediatric patients diagnosed with posterior fossa tumors and undergoing surgery at Beijing Children's Hospital from July 2013 to December 2023 was analyzed. Clinical variables gender, age at surgery, tumor characteristics, hydrocephalus, surgical route and pathology were collected. LSM was used to link tumor locations with CMS outcomes. Lasso regression and logistic regression were employed for feature selection and model construction, respectively. Model performance was assessed using area under the curve (AUC) and accuracy metrics. RESULTS: The study included 197 patients in total, with CMS rates consistent across training, validation, and prospective groups. Significant associations were found between CMS and gender, tumor type, hydrocephalus, paraventricular edema, surgical route, and pathology. A predictive model combining voxel location data from LSM with clinical factors achieved high predictive performance (C-index: training 0.956, validation 0.933, prospective 0.892). Gender, pathology, and voxel location were identified as key predictors for CMS. CONCLUSION: The study established an effective predictive model for CMS in pediatric posterior fossa tumor patients, leveraging LSM data and clinical factors. The model's accuracy and robustness suggest its potential utility in clinical practice for early CMS risk assessment and intervention planning.

8.
Genome Biol ; 25(1): 232, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198826

RESUMO

BACKGROUND: The relationship between human gut microbiota and high-altitude hypoxia acclimatization remains highly controversial. This stems primarily from uncertainties regarding both the potential temporal changes in the microbiota under such conditions and the existence of any dominant or core bacteria that may assist in host acclimatization. RESULTS: To address these issues, and to control for variables commonly present in previous studies which significantly impact the results obtained, namely genetic background, ethnicity, lifestyle, and diet, we conducted a 108-day longitudinal study on the same cohort comprising 45 healthy Han adults who traveled from lowland Chongqing, 243 masl, to high-altitude plateau Lhasa, Xizang, 3658 masl, and back. Using shotgun metagenomic profiling, we study temporal changes in gut microbiota composition at different timepoints. The results show a significant reduction in the species and functional diversity of the gut microbiota, along with a marked increase in functional redundancy. These changes are primarily driven by the overgrowth of Blautia A, a genus that is also abundant in six independent Han cohorts with long-term duration in lower hypoxia environment in Shigatse, Xizang, at 4700 masl. Further animal experiments indicate that Blautia A-fed mice exhibit enhanced intestinal health and a better acclimatization phenotype to sustained hypoxic stress. CONCLUSIONS: Our study underscores the importance of Blautia A species in the gut microbiota's rapid response to high-altitude hypoxia and its potential role in maintaining intestinal health and aiding host adaptation to extreme environments, likely via anti-inflammation and intestinal barrier protection.


Assuntos
Aclimatação , Altitude , Microbioma Gastrointestinal , Hipóxia , Humanos , Animais , Adulto , Masculino , Hipóxia/genética , Camundongos , Feminino , Estudos Longitudinais , Doença da Altitude/microbiologia , Doença da Altitude/genética , Pessoa de Meia-Idade
9.
Ecotoxicol Environ Saf ; 283: 116784, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39088896

RESUMO

2-ethylhexyl diphenyl phosphate (EHDPHP) is a widely used organophosphorus flame retardant and plasticizer, which is commonly found in the environment. EHDPHP not only potentially harms the environment but also causes different degrees of damage to the organism. In this study, the duodenum of chicks was selected as the potential toxic target organ to explore the mechanism of duodenal injury induced by EHDPHP exposure. Ninety one-day-old healthy male chicks were selected and randomly divided into C1(control group), C2(solvent control group), L(800 mg/kg), M(1600 mg/kg), H(3200 mg/kg) according to different doses of EHDPHP after one week of environmental adaptation. The chicks were given continuous gavage for 14 d, 28 d, and 42 d. It was found that constant exposure to EHDPHP caused an increase in duodenal MDA content, a decrease in P-gp, SOD, GSH-Px activities, and a decrease in duodenal mucosal immune factor (sIgA, GSH-Px). The expression of sIgM and mucosal link proteins (CLDN, OCLN, ZO-1, JAM) decreased, and the expression of the inflammatory protein (NF-κB, COX2) in duodenal tissues was up-regulated. The results showed that continuous exposure to EHDPHP could cause duodenal oxidative stress, inflammation, and mucosal barrier damage in chicks, which provided a basis for studying the mechanism of toxic damage caused by EHDPHP in poultry.


Assuntos
Galinhas , Duodeno , Retardadores de Chama , Estresse Oxidativo , Animais , Estresse Oxidativo/efeitos dos fármacos , Duodeno/efeitos dos fármacos , Duodeno/patologia , Duodeno/metabolismo , Masculino , Retardadores de Chama/toxicidade , Inflamação/induzido quimicamente , Inflamação/patologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Compostos Organofosforados/toxicidade , Organofosfatos/toxicidade
10.
Nat Commun ; 15(1): 6740, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39112531

RESUMO

Glioblastoma (GBM) is the most common brain tumor and remains incurable. Primary GBM cultures are widely used tools for drug screening, but there is a lack of genomic and pharmacological characterization for these primary GBM cultures. Here, we collect 50 patient-derived glioma cell (PDGC) lines and characterize them by whole genome sequencing, RNA sequencing, and drug response screening. We identify three molecular subtypes among PDGCs: mesenchymal (MES), proneural (PN), and oxidative phosphorylation (OXPHOS). Drug response profiling reveals that PN subtype PDGCs are sensitive to tyrosine kinase inhibitors, whereas OXPHOS subtype PDGCs are sensitive to histone deacetylase inhibitors, oxidative phosphorylation inhibitors, and HMG-CoA reductase inhibitors. PN and OXPHOS subtype PDGCs stably form tumors in vivo upon intracranial transplantation into immunodeficient mice, whereas most MES subtype PDGCs fail to form tumors in vivo. In addition, PDGCs cultured by serum-free medium, especially long-passage PDGCs, carry MYC/MYCN amplification, which is rare in GBM patients. Our study provides a valuable resource for understanding primary glioma cell cultures and clinical translation and highlights the problems of serum-free PDGC culture systems that cannot be ignored.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Animais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Camundongos , Glioma/genética , Glioma/patologia , Glioma/tratamento farmacológico , Glioma/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Feminino , Masculino , Sequenciamento Completo do Genoma , Ensaios Antitumorais Modelo de Xenoenxerto , Genômica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Multiômica
11.
Langmuir ; 40(35): 18610-18618, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39172731

RESUMO

Low-cost sodium ion batteries are of great significance in large-scale energy storage applications. With its high energy density and simple synthesis process, layered transition-metal oxides have become one of the most likely sodium ion battery cathode materials to replace lithium ion batteries in the energy storage market. Here, we report a prilling and MoS2 coating strategy to prepare the spherical cathode material. The spherical micronano particles shorten the diffusion path of Na+, restrain the complexity phase transitions, and enhance the tap density of the materials. In addition, the MoS2 coating improves the electrical conductivity of the material and the structural stability of the cathode material in air. The initial specific discharge capacity is 148.4 mA h g-1 at 0.1 C, which can be maintained at 128.9 mA h g-1 after exposure to air for 10 days. This method dramatically improves the energy density and structural stability of the cathode material, which provides a new scheme for preparing high-performance sodium ion batteries.

12.
Small ; : e2405158, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39183524

RESUMO

The development of Cu-based atomic dispersed catalysts with tailored coordination environments represents a significant step forward in enhancing the electrocatalytic reduction of nitrate to ammonia. By precisely modulating the electronic structures of Cu active centers, the binding strength of the *NO3 intermediates is successfully tuned, thereby substantially improving the catalytic activity toward electrochemical nitrate reduction reaction (eNO3RR). This study reveals that the N4-coordinated Cu single-atom catalyst (Cu-SAC) exhibits superior performance due to its robust interaction with coordinating atoms. Notably, this optimized catalyst achieves a low limiting potential of -0.38 V, while the dual-atom system further reduces this value to -0.32 V, demonstrating exceptional activity. Detailed electronic structure analysis, including the examination of d-band centers, Bader charges, and projected density of states (PDOS), provides a comprehensive understanding of the origin of this high activity. Specifically, the high and concentrated density of states near the Fermi level plays a crucial role in facilitating the electrocatalytic nitrate reduction process. This work not only offers crucial insights into the underlying mechanisms of eNO3RR but also provides valuable guidelines for the rational design of highly efficient electrocatalysts for this important reaction.

13.
Biol Trace Elem Res ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958867

RESUMO

Cadmium(Cd) is a toxic heavy metal widely present in the environment, capable of accumulating in the liver and causing liver damage. In this study, the mechanism of cadmium-induced liver fibrosis in chickens was investigated from the perspective of hepatocyte epithelial-mesenchymal transition (EMT) based on the establishment of a model of chicken cadmium toxicity and a model of cadmium-stained cells in a chicken hepatocellular carcinoma cell line (LMH). The 7-day-old chickens were randomly divided into the regular group (C group) and cadmium poisoning group (Cd group), and the entire test cycle was 60 days. Three sampling time points of 20 days, 40 days, and 60 days were established. By testing the liver coefficient, histopathological and ultrastructural changes in chicken livers were observed. The enzyme activities of liver function and the expression changes of fibrosis markers (COL1A1, Fibronectin), epithelial-mesenchymal transition markers (E-cadherin, Vimentin, and α-SMA), and the critical factors of the TGF-ß/SMAD signaling pathway (TGF-ß1, SMAD 2, and SMAD 3) were detected in the liver expression changes. The results showed that at the same sampling time point, the chicken liver coefficient in group Cd was significantly higher than that in control group (P < 0.01); the activities of the liver function enzymes ALT and AST in chickens in the Cd group were significantly higher than those in the C group (P < 0.01); liver hepatocytes degenerated and necrotic, the number of erythrocytes in the blood vessels was increased, and inflammatory cells infiltrated in the sinusoidal gap; the perisinusoidal gap of the liver was enlarged, and there was an apparent aggregation of collagen fibers in the intervening period as seen by transmission electron microscopy. The results of Masson staining showed that the percentage of fiber area was significantly higher in the chickens' livers of the Cd group. The fiber area percentage was significantly higher. The results of real-time fluorescence quantitative PCR and Western Blot showed that the expression of E-cadherin in the livers of chickens in the Cd group was significantly lower than that in the C group (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-ß1, SMAD 2, and SMAD 3 was significantly higher than that in the C group (P < 0.01). The results of in vitro assays showed that in the LMH cell model established by adding trimethylamine N-oxide, an activator of the TGF-ß/SMAD signaling pathway, and oxidized picric acid, an inhibitor of the TGF-ß/SMAD signaling pathway, the expression of E-cadherin was significantly reduced in cadmium-stained LMH cells (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-ß, SMAD 2, and SMAD 3 was significantly elevated (P < 0.01). Cadmium and Trimethylamine N-oxide, an activator of the TGF-ß/SMAD signaling pathway, promoted the expression of these factors. In contrast, the inhibitor of the TGF-ß/SMAD signaling pathway, Oxymatrine, a TGF-ß/SMAD signaling pathway inhibitor, significantly slowed down these changes. These results suggest that cadmium induces hepatic epithelial-mesenchymal transition by activating the TGF-ß/SMAD signaling pathway in chicken hepatocytes, promoting hepatic fibrosis.

14.
Acta Pharmacol Sin ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054339

RESUMO

Sjogren's syndrome (SS) is a chronic, progressive autoimmune disorder characterized by gland fibrosis. We previously found a close correlation between gland fibrosis and the expression of G protein-coupled receptor kinase 2 (GRK2). In this study we explored the pathological and therapeutic significance of GRK2 in SS. Submandibular gland (SMG) antigen-induced SS mouse model was established in WT and GRK2+/- mice. We showed that the expression levels of GRK2 were significantly up-regulated in glandular tissue and positively correlated with fibrotic morphology in SS patients and mice. Hemizygous knockout of GRK2 significantly inhibited the gland fibrosis. In mouse salivary gland epithelial cells (SGECs), we demonstrated that GRK2 interacted with Smad2/3 to positively regulate the activation of TGF-ß-Smad signaling with a TGF-ß-GRK2 positive feedback loop contributing to gland fibrosis. Hemizygous knockout of GRK2 attenuated TGF-ß-induced collagen I production in SGECs in vitro and hindered gland fibrosis in murine SS though preventing Smad2/3 nuclear translocation. Around 28 days post immunization with SMG antigen, WT SS mice were treated with a specific GRK2 inhibitor paroxetine (Par, 5 mg·kg-1·d-1, i.g. for 19 days). We found that Par administration significantly attenuated gland fibrosis and alleviated the progression of SS in mice. We conclude that genetic knockdown or pharmacological inhibition of GRK2 significantly attenuates gland fibrosis and alleviates the progression of SS. GRK2 binds to Smad2/3 and positively regulates the activation of TGF-ß-Smad signaling. A TGF-ß-GRK2 positive feedback loop contributes to gland fibrosis. Our research points out that GRK2 could be a promising therapeutic target for treating SS.

15.
Inorg Chem ; 63(29): 13181-13185, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38985134

RESUMO

The development of a low-cost and efficient oxygen evolution reaction (OER) electrode is of critical importance for water electrolysis technologies. The general approach to achieving a high-efficiency OER electrode is to regulate catalytic material structures by synthetic control. Here we reported an orthogonal approach to obtaining the OER electrode without intentional design and synthesis, namely, recycling MnO2 cathodes from failed rechargeable aqueous batteries and investigating them as ready-made catalytic electrodes. The recycled MnO2 cathode showed very little Zn2+ storage capacity but surprisingly high OER activity with a low overpotential of 307 mV at 10 mA cm-2 and a small Tafel slope of 77.9 mV dec-1, comparable to the state-of-the-art RuO2 catalyst (310 mV, 86.9 mV dec-1). In situ electrochemical and theoretical studies jointly revealed that the accelerated OER kinetics of the recycled MnO2 electrode was attributed to the enlarged active surface area of MnO2 and optimized electronic structure of Mn sites. This work suggests failed battery cathodes as successful catalysis electrodes for sustainable energy development.

16.
Front Public Health ; 12: 1353384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38939565

RESUMO

Background: Ozone pollution is associated with cardiovascular disease mortality, and there is a high correlation between different pollutants. This study aimed to assess the association between ozone and cardiovascular disease deaths and the resulting disease burden in Nanjing, China. Methods: A total of 151,609 deaths from cardiovascular disease were included in Nanjing, China from 2013 to 2021. Daily data on meteorological and air pollution were collected to apply a generalized additional model with multiple pollutants to perform exposure-response analyses, stratification analysis, and evaluation of excess deaths using various standards. Results: In the multi-pollutant model, an increase of 10 µg/m3 in O3 was significantly associated with a 0.81% (95%CI: 0.49, 1.12%) increase in cardiovascular disease deaths in lag05. The correlation weakened in both the single-pollutant model and two-pollutant models, but remained more pronounced in females, the older group, and during warm seasons. From 2013 to 2021, the number of excess deaths attributed to ozone exposure in cardiovascular disease continued to rise with an increase in ozone concentration in Nanjing. If the ozone concentration were to be reduced to the WHO standard and the minimum level, the number of deaths would decrease by 1,736 and 10,882, respectively. Conclusion: The risk of death and excess deaths from cardiovascular disease due to ozone exposure increases with higher ozone concentration. Reducing ozone concentration to meet WHO standards or lower can provide greater cardiovascular disease health benefits.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Doenças Cardiovasculares , Exposição Ambiental , Ozônio , Ozônio/análise , Ozônio/toxicidade , Ozônio/efeitos adversos , Humanos , Doenças Cardiovasculares/mortalidade , China/epidemiologia , Feminino , Masculino , Poluentes Atmosféricos/análise , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversos , Pessoa de Meia-Idade , Idoso , Estações do Ano , Adulto , Rios
17.
Chem Commun (Camb) ; 60(58): 7467-7470, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38934088

RESUMO

A finely controlled concentration polarization environment was deliberately created to fabricate a three-dimensional ordered Zn metal anode with (002)-dominated planes, which enabled a high-rate aqueous Ni-Zn pouch cell with a high discharge capacity of 187.3 mA h g-1 at 50 C, and a capacity retention of 94.7% and an average Coulombic efficiency of 99.8% for 500 charge/discharge cycles.

18.
Environ Technol ; : 1-12, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940265

RESUMO

Antibiotics in water will cause serious harm to human health and ecosystem. Carbon-based materials and transition metals activated peroxodisulfate (PDS) to produce active species, which can degrade residual antibiotics in water. In this paper, Cu/CNF (carbon nanofibers) composites were first prepared by introducing Cu into CNF using electrostatic spinning technology, which was used to activate PDS to degrade tetracycline (TC). The degradation efficiency of Cu/CNF/PDS was 36.23% higher than that of CNF/PDS. The reason is that introducing Cu can increase the number of surface functional groups and specific surface area of CNF, and then improve the catalytic performance. The functional groups and Cu species are the active sites for catalytic PDS. Moreover, the main ways to degrade TC in the Cu/CNF/PDS system are singlet oxygen (1O2) and electron transfer. Based on the above analysis, we modified CNF with transition metal salts, prepared efficient environmental functional materials, and used them for PDS activation, providing a theoretical basis and technical support for the degradation of antibiotic pollutants and creating new ideas for other research.

19.
Brain Res Bull ; 213: 110981, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38777132

RESUMO

INTRODUCTION: The medial prefrontal cortex (mPFC) forms output pathways through projection neurons, inversely receiving adjacent and long-range inputs from other brain regions. However, how afferent neurons of mPFC are affected by chronic stress needs to be clarified. In this study, the effects of chronic restraint stress (CRS) on the distribution density of mPFC dendrites/dendritic spines and the projections from the cortex and subcortical brain regions to the mPFC were investigated. METHODS: In the present study, C57BL/6 J transgenic (Thy1-YFP-H) mice were subjected to CRS to establish an animal model of depression. The infralimbic (IL) of mPFC was selected as the injection site of retrograde AAV using stereotactic technique. The effects of CRS on dendrites/dendritic spines and afferent neurons of the mPFC IL were investigaed by quantitatively assessing the distribution density of green fluorescent (YFP) positive dendrites/dendritic spines and red fluorescent (retrograde AAV recombinant protein) positive neurons, respectively. RESULTS: The results revealed that retrograde tracing virus labeled neurons were widely distributed in ipsilateral and contralateral cingulate cortex (Cg1), second cingulate cortex (Cg2), prelimbic cortex (PrL), infralimbic cortex, medial orbital cortex (MO), and dorsal peduncular cortex (DP). The effects of CRS on the distribution density of mPFC red fluorescence positive neurons exhibited regional differences, ranging from rostral to caudal or from top to bottom. Simultaneously, CRS resulted a decrease in the distribution density of basal, proximal and distal dendrites, as well as an increase in the loss of dendritic spines of the distal dendrites in the IL of mPFC. Furthermore, varying degrees of red retrograde tracing virus fluorescence signals were observed in other cortices, amygdala, hippocampus, septum/basal forebrain, hypothalamus, thalamus, mesencephalon, and brainstem in both ipsilateral and contralateral brain. CRS significantly reduced the distribution density of red fluorescence positive neurons in other cortices, hippocampus, septum/basal forebrain, hypothalamus, and thalamus. Conversely, CRS significantly increased the distribution density of red fluorescence positive neurons in amygdala. CONCLUSION: Our results suggest a possible mechanism that CRS leads to disturbances in synaptic plasticity by affecting multiple inputs to the mPFC, which is characterized by a decrease in the distribution density of dendrites/dendritic spines in the IL of mPFC and a reduction in input neurons of multiple cortices to the IL of mPFC as well as an increase in input neurons of amygdala to the IL of mPFC, ultimately causing depression-like behaviors.


Assuntos
Depressão , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Córtex Pré-Frontal , Restrição Física , Estresse Psicológico , Animais , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/metabolismo , Estresse Psicológico/patologia , Estresse Psicológico/metabolismo , Camundongos , Depressão/patologia , Masculino , Espinhas Dendríticas/patologia , Modelos Animais de Doenças , Vias Aferentes , Dendritos/patologia , Dendritos/metabolismo , Neurônios Aferentes/patologia , Neurônios Aferentes/metabolismo , Encéfalo/patologia , Encéfalo/metabolismo
20.
Comput Biol Med ; 176: 108530, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38749324

RESUMO

As an autoimmune-mediated inflammatory demyelinating disease of the central nervous system, multiple sclerosis (MS) is often confused with cerebral small vessel disease (cSVD), which is a regional pathological change in brain tissue with unknown pathogenesis. This is due to their similar clinical presentations and imaging manifestations. That misdiagnosis can significantly increase the occurrence of adverse events. Delayed or incorrect treatment is one of the most important causes of MS progression. Therefore, the development of a practical diagnostic imaging aid could significantly reduce the risk of misdiagnosis and improve patient prognosis. We propose an interpretable deep learning (DL) model that differentiates MS and cSVD using T2-weighted fluid-attenuated inversion recovery (FLAIR) images. Transfer learning (TL) was utilized to extract features from the ImageNet dataset. This pioneering model marks the first of its kind in neuroimaging, showing great potential in enhancing differential diagnostic capabilities within the field of neurological disorders. Our model extracts the texture features of the images and achieves more robust feature learning through two attention modules. The attention maps provided by the attention modules provide model interpretation to validate model learning and reveal more information to physicians. Finally, the proposed model is trained end-to-end using focal loss to reduce the influence of class imbalance. The model was validated using clinically diagnosed MS (n=112) and cSVD (n=321) patients from the Beijing Tiantan Hospital. The performance of the proposed model was better than that of two commonly used DL approaches, with a mean balanced accuracy of 86.06 % and a mean area under the receiver operating characteristic curve of 98.78 %. Moreover, the generated attention heat maps showed that the proposed model could focus on the lesion signatures in the image. The proposed model provides a practical diagnostic imaging aid for the use of routinely available imaging techniques such as magnetic resonance imaging to classify MS and cSVD by linking DL to human brain disease. We anticipate a substantial improvement in accurately distinguishing between various neurological conditions through this novel model.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Aprendizado Profundo , Esclerose Múltipla , Humanos , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Masculino , Imageamento por Ressonância Magnética/métodos , Feminino , Redes Neurais de Computação , Interpretação de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Adulto , Neuroimagem/métodos
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