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1.
ChemSusChem ; : e202301827, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985026

RESUMO

Extensive research is underway to achieve carbon neutrality through the production of green hydrogen via water electrolysis, powered by renewable energy. Polymer membrane water electrolyzers, such as proton exchange membrane water electrolyzer (PEMWE) and anion exchange membrane water electrolyzer (AEMWE), are at the forefront of this research. Developing highly active and durable electrode catalysts is very important for commercializing these electrolyzers. However, most research is conducted in half-cell setups, which may not fully represent the catalysts' effectiveness in membrane-electrode-assembly (MEA) devices. This review explores the catalysts developed for high-performance PEMWE and AEMWE MEA systems. Only the catalysts reporting the MEA performance were discussed in this review. In PEMWE, strategies aim to minimize Ir use for oxygen evolution reaction (OER) by maximizing activity, employing metal oxide-based supports, integrating secondary elements into IrOx lattices, or exploring non-Ir materials. For AEMWE, the emphasis is on enhancing the performance of NiFe-based and Co-based catalysts by improving electrical conductivity and mass transport. Pt-based and Ni-based catalysts for hydrogen evolution reaction (HER) in AEMWE are also examined. Additionally, this review discusses the unique considerations for catalysts operating in pure water within AEMWE systems.

2.
Sci Rep ; 14(1): 14950, 2024 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942754

RESUMO

This study utilized arterial spin labeling-magnetic resonance imaging (ASL-MRI) to explore the developmental trajectory of brain activity associated with attention deficit hyperactivity disorder (ADHD). Pulsed arterial spin labeling (ASL) data were acquired from 157 children with ADHD and 109 children in a control group, all aged 6-12 years old. Participants were categorized into the age groups of 6-7, 8-9, and 10-12, after which comparisons were performed between each age group for ASL analysis of cerebral blood flow (CBF). In total, the ADHD group exhibited significantly lower CBF in the left superior temporal gyrus and right middle frontal gyrus regions than the control group. Further analysis revealed: (1) The comparison between the ADHD group (N = 70) aged 6-7 and the age-matched control group (N = 33) showed no statistically significant difference between. (2) However, compared with the control group aged 8-9 (N = 39), the ADHD group of the same age (N = 53) showed significantly lower CBF in the left postcentral gyrus and left middle frontal gyrus regions. (3) Further, the ADHD group aged 10-12 (N = 34) demonstrated significantly lower CBF in the left superior occipital region than the age-matched control group (N = 37). These age-specific differences suggest variations in ADHD-related domains during brain development post age 6-7.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Circulação Cerebrovascular , Imageamento por Ressonância Magnética , Marcadores de Spin , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico por imagem , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Circulação Cerebrovascular/fisiologia , Estudos de Casos e Controles , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia
3.
Nano Lett ; 24(23): 7025-7032, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38832667

RESUMO

Three-dimensional gold and its alloyed nanoporous structures possess high surface areas and strong local electric fields, rendering them ideal substrates for plasmonic molecular detection. Despite enhancing plasmonic properties and altering molecular interactions, the effect of alloy composition on molecular detection capability has not yet been explored. Here, we report molecular interactions between nanoporous gold alloys and charged molecules by controlling the alloy composition. We demonstrate enhanced adsorption of negatively charged molecules onto the alloy surface due to positively charged gold atoms and a shifted d-band center through charge transfer between gold and other metals. Despite similar EM field intensities, nanoporous gold with silver (Au/Ag) achieves SERS enhancement factors (EF) up to 6 orders of magnitude higher than those of other alloys for negatively charged molecules. Finally, nanoporous Au/Ag detects amyloid-beta at concentrations as low as approximately 1 fM, with SERS EF up to 10 orders of magnitude higher than that of a monolayer of Au nanoparticles.

5.
Int J Med Robot ; 20(4): e2653, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38934235

RESUMO

BACKGROUND: Traditional open surgery for bone tumours sometimes has as a consequence an excessive removal of healthy bone tissue because of the limitations of rigid surgical instruments, increasing infection risk and recovery time. METHODS: We propose a remote robot with a 4.5-mm diameter bendable end-effector, offering four degrees of freedom for accessing the inside of the bone and performing tumour debridement. The preclinical studies evaluated the effectiveness, clinical scenario, and usability across 12 total surgeries-six phantom surgeries and six bovine bone surgeries. Evaluation criteria included skin incision size, bone window size, surgical time, removal rate, and conversion to open surgery. RESULTS: Preclinical studies demonstrated that the robotic approach requires significantly smaller incision size and procedure times than traditional open curettage. CONCLUSION: This study validated the performance of the proposed system by assessing its preclinical effectiveness and optimising surgical methods using human phantom and bovine bone tumour models.


Assuntos
Neoplasias Ósseas , Desenho de Equipamento , Procedimentos Cirúrgicos Robóticos , Animais , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/instrumentação , Neoplasias Ósseas/cirurgia , Bovinos , Projetos Piloto , Humanos , Imagens de Fantasmas , Osso e Ossos/cirurgia
6.
Microorganisms ; 12(5)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38792793

RESUMO

The VITEK MS PRIME (bioMérieux, Marcy-l'Étoile, France), a newly developed matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) system, alongside the VITEK PICKME pen (PICKME), offers easy sample preparation for bacteria and yeasts. The VITEK MS PRIME also offers two software platforms for filamentous fungi: the IVD database and the RUO database. Our study evaluated its identification agreement on 320 clinical isolates of bacteria and yeasts, comparing PICKME and traditional wooden toothpick sampling techniques against MicroIDSys Elite (ASTA) results. Additionally, we assessed the IVD (v3.2) and SARAMIS (v4.16) RUO databases on 289 filamentous fungi against molecular sequencing. The concordance rates for species-level identification of bacteria and yeasts were about 89.4% (286/320) between the PICKME and wooden toothpick, and about 83.4-85.3% between the VITEK MS PRIME and ASTA MicroIDSys Elite. Retesting with PICKME improved concordance to 91.9%. For filamentous fungi, species-level identification reached 71.3% with the IVD database and 85.8% with RUO, which significantly enhanced basidiomycetes' identification from 35.3% to 100%. Some strains in the IVD database, like Aspergillus versicolor, Exophiala xenobiotica, and Nannizzia gypsea, failed to be identified. The VITEK MS PRIME with PICKME offers reliable and efficient microorganism identification. For filamentous fungi, combined use of the RUO database can be beneficial, especially for basidiomycetes.

7.
JACS Au ; 4(5): 1673-1675, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38818070
8.
ACS Appl Mater Interfaces ; 16(22): 28731-28741, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38781021

RESUMO

Gas diffusion electrodes (GDEs) are extensively used for high current density electrochemical CO2 electrolysis (ECO2R), enabled by significantly reducing mass transfer resistance of CO2 to the catalyst layer. Conventionally, these GDEs are based upon hydrophobic carbon-based gas-diffusion layers (GDLs) that facilitate the gas transport; however, these supports are prone to flood with electrolyte during electrolysis. This potential-induced flooding, known as electrowetting, is related to the inherent conductivity of carbon and limits the activity of ECO2R. To investigate the effect of electrical conductivity more carefully, a GDE is constructed based on a Cu mesh with a nonconductive microporous GDL applied to this substrate, the latter composed of a mixture of metal oxide and polytetrafluoroethylene. With alumina as the metal oxide, a stable operation is obtained at -200 mA cm-2 with 70% selectivity for ECO2R (with over half toward C2+ products) without flooding as observed by in situ microscopy. On the contrary, with a Vulcan carbon-based GDL, the initial activity is rapidly lost as severe flooding ensues. It is reasoned that electrowetting is averted by virtue of the nonconductive nature of alumina, providing a new perspective on alternative GDL compositions and their influence on ECO2R performance.

9.
Res Aging ; : 1640275241248773, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38657141

RESUMO

This study aimed to examine the impact of COVID-19 on loneliness among rural older women in senior cohousing in Korea. Using a natural experimental study design, we investigated how the pandemic-induced closure of cohousing affected the former residents' loneliness. The sample comprised 84 cohousing residents and 51 individuals in conventional homes. The dependent variable is loneliness, and the independent variables include housing transition, social contact, and support from neighbors and friends. Our findings from fixed effect regression models showed former cohousing residents were less likely to experience loneliness when they had more contact with their friends and neighbors, while negative relationships exacerbated feelings of loneliness. Sharing meals and participating in activities with friends and neighbors in cohousing helped the residents develop effective coping strategies. Senior cohousing in rural areas has the potential to strengthen social ties and protect the most vulnerable subgroup of older adults from social isolation and loneliness.

10.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612663

RESUMO

Some studies have demonstrated the effects of particulate matter (PM) on chronic rhinosinusitis with nasal polyps (CRSwNP) development, as well as the therapeutic role of retinoic acid (RA) in nasal polypogenesis. However, the immunologic effect of PM in innate lymphoid cells (ILCs) and the exact mechanism of the therapeutic effect of RA remain unclear. Therefore, the present study investigated the effects of fine-dust-induced inflammation in CRSwNP and the mechanisms of the therapeutic effect of RA. PM2.5 exposure exacerbated pathological damage in the nasal mucosa of mice with nasal polyps (NP) via upregulation of type 2 inflammation. Additionally, PM2.5 exposure increased the expression of type 2 cytokines and epithelial-cell-derived cytokines (IL-33 and IL-25) significantly, as well as the ILC populations in human-NP-derived epithelial cells (HNECs). Moreover, RA supplementation significantly increased the expression of ILCreg in Lin-CD45+CD127+ cells, which in turn increased the levels of the anti-inflammatory cytokine IL-10. The findings suggest that PM2.5 exposures could aggravate the CRSwNP type 2 inflammation, and RA treatment may ameliorate fine-dust-induced inflammation by modulating the innate immune response.


Assuntos
Imunidade Inata , Pólipos Nasais , Humanos , Animais , Camundongos , Linfócitos , Inflamação/tratamento farmacológico , Citocinas , Poeira , Mucosa Nasal , Material Particulado/toxicidade
11.
Adv Mater ; : e2403896, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38663435

RESUMO

Small-reactor-based polymerase chain reaction (PCR) has attracted considerable attention. A significant number of tiny reactors must be prepared in parallel to capture, amplify, and accurately quantify few target genes in clinically relevant large volume, which, however, requires sophisticated microfabrication and longer sample-to-answer time. Here, single plasmonic cavity membrane is reported that not only enriches and captures few nucleic acids by taking advantage of both capillarity and hydrodynamic trapping but also quickly amplifies them for sensitive plasmonic detection. The plasmonic cavity membrane with few nanoliters in a void volume is fabricated by self-assembling gold nanorods with SiO2 tips. Simulations reveal that hydrodynamic stagnation between the SiO2 tips is mainly responsible for the trapping of the nucleic acid in the membrane. Finally, it is shown that the plasmonic cavity membrane is capable of enriching severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genes up to 20 000-fold within 1 min, amplifying within 3 min, and detecting the trace genes as low as a single copy µL-1. It is anticipated that this work not only expands the utility of PCR but also provides an innovative way of the enrichment and detection of trace biomolecules in a variety of point-of-care testing applications.

12.
Brain Stimul ; 17(2): 405-412, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38537689

RESUMO

Transcranial focused ultrasound (tFUS) neuromodulation emerges as a promising non-invasive approach for improving neurological conditions. Extinction of conditioned fear has served as a prime model for exposure-based therapies for anxiety disorders. We investigated whether tFUS stimulation to a critical brain area, the infralimbic subdivision of the prefrontal cortex (IL), could facilitate fear extinction using rats. In a series of experiments, tFUS was delivered to the IL of a freely-moving rat and compared to sham stimulation (tFUS vs. SHAM). Initially, Fos expression in the IL was measured shortly after the stimulation. The results show that Fos expression was significantly increased in the IL but not in the neighboring regions compared to SHAM. Subsequently, two groups of rats were subjected to fear conditioning, extinction, and retention while receiving stimulation during the extinction. Rats in the tFUS group froze significantly less than SHAM during both extinction and retention tests. Importantly, the reduced freezing in the tFUS group was not attributable to non-specific effect such as auditory noise, as both groups demonstrated a similar level of locomotive activity in an open field regardless of the stimulation condition. Finally, we replicated the procedure with a shortened conditioning-to-extinction interval (15 min) to induce immediate extinction deficit. The tFUS group showed a facilitated reduction in freezing during the extinction, which persisted in the subsequent retention session compared to SHAM. In summary, the current findings suggest that tFUS stimulation in the IL facilitates fear extinction, offering a potential therapeutic regimen for fear-related psychiatric disorders.


Assuntos
Extinção Psicológica , Medo , Córtex Pré-Frontal , Animais , Medo/fisiologia , Extinção Psicológica/fisiologia , Ratos , Masculino , Córtex Pré-Frontal/fisiologia , Ratos Sprague-Dawley , Condicionamento Clássico/fisiologia
13.
Clin Ophthalmol ; 18: 735-742, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476357

RESUMO

Purpose: Long-term patient satisfaction may influence patients' perspectives of the quality of care and their relationship with their providers. This is a follow up to a comparative effectiveness study investigating oral to intravenous sedation (OIV study). The OIV study found that oral sedation was noninferior in patient satisfaction to standard intravenous (IV) sedation for anterior segment and vitreoretinal surgeries. This study aims to determine if patient satisfaction with oral sedation remained noninferior long term. Patients and Methods: Patients were re-interviewed using the same satisfaction survey given during the OIV study. Statistical analysis involved t-tests for noninferiority of the long-term mean satisfaction score of oral and IV sedation. We also compared the original mean satisfaction score and the follow-up mean satisfaction score for each type of sedation and for both groups combined. Results: Participants were interviewed at a median of 1225.5 days (range 754-1675 days) from their surgery. The original mean satisfaction score was 5.26 ± 0.79 for the oral treatment group (n = 52) and 5.27 ± 0.64 for the intravenous treatment group (n = 46), demonstrating noninferiority with a difference in mean satisfaction score of 0.015 (p < 0.0001). The follow-up mean satisfaction score was 5.23 ± 0.90 for oral sedation and 5.60 ± 0.61 for IV sedation, with a difference in the mean satisfaction score of 0.371 (p = 0.2071). Satisfaction scores did not differ between the original mean satisfaction score and the follow-up mean satisfaction score for the oral treatment group alone (p = 0.8367), but scores in the intravenous treatment group increased longitudinally (p = 0.0004). Conclusion: In this study, long-term patient satisfaction with oral sedation was not noninferior to satisfaction with IV sedation, unlike our findings with short-term patient satisfaction in our original study. Patient satisfaction also remained unchanged over time for the oral treatment group, but patients in the intravenous treatment group reported higher long-term satisfaction with their anesthesia experience compared to the immediate post-operative period.

14.
Int J Mol Sci ; 25(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339162

RESUMO

Globally, women have been adopting oocyte cryopreservation (OC) for fertility preservation for various reasons, such as inevitable gonadotoxic treatment for specific pathologic states and social preferences. While conventional vitrification (C-VIT) has improved the success rate of OC, challenges of possible toxicities of high-concentration cryoprotective agents and osmotic stress persist. To overcome these challenges, we evaluated the ultra-fast vitrification (UF-VIT) method, which reduces the equilibration solution stage exposure time compared to C-VIT by observing mouse oocyte intracellular organelles and embryonic development. Consequently, compared to fresh mouse oocytes, UF-VIT presented significant differences only in endoplasmic reticulum (ER) intensity and mitochondrial (MT) distribution. Meanwhile, C-VIT showed substantial differences in the survival rate, key ER and MT parameters, and embryonic development rate. UF-VIT exhibited considerably fewer negative effects on key MT parameters and resulted in a notably higher blastocyst formation rate than C-VIT. Meiotic spindle (spindle and chromosomes) morphology showed no significant changes between the groups during vitrification/warming (VW), suggesting that VW did not negatively affect the meiotic spindle of the oocytes. In conclusion, UF-VIT seems more effective in OC owing to efficient cytoplasmic water molecule extraction, osmotic stress reduction, and minimization of cell contraction and expansion amplitude, thus compensating for the drawbacks of C-VIT.


Assuntos
Crioprotetores , Vitrificação , Feminino , Animais , Camundongos , Humanos , Crioprotetores/farmacologia , Pressão Osmótica , Criopreservação/métodos , Oócitos
15.
Knee Surg Relat Res ; 36(1): 9, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347607

RESUMO

PURPOSE: The aim of this study is to evaluate the results of high tibial osteotomy (HTO) in patients with bone marrow edema (BME) and assess the effect of factors on the subsequent results. METHODS: A total of 138 patients who underwent medial open-wedge HTO using locking plate were included in this study. BME was observed in 108 patients using preoperative magnetic resonance imaging. Clinical results were evaluated before HTO and postoperatively at 12 months. Moreover, we evaluated the factors affecting the clinical results. RESULTS: The clinical scores were all significantly improved regardless of the presence of BME. There were no differences in improvement of clinical scores between patients with BME and without BME. Patients with BME showed higher postoperative Western Ontario and McMaster Universities Arthritis Index (WOMAC) stiffness scores than patients without BME. Furthermore, patients with BME on both the femur and tibia showed lower Knee Society function scores than patients with BME on either the femur or the tibia. Patients with large BME lesions exhibited a lower Hospital for Special Surgery score and WOMAC pain scores, postoperatively. In patients with BME, patients with undercorrection showed significantly lower improvement in WOMAC pain scores compared with patients with acceptable correction. CONCLUSIONS: The clinical improvement after HTO in patients with varus and medial osteoarthritis was not different regardless of the presence or absence of BME. However, accurate alignment should be considered essential for achieving better clinical outcomes in patients with preoperative BME.

16.
Arch Gynecol Obstet ; 310(1): 461-467, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38252305

RESUMO

PURPOSE: To investigate the effect of intravenous MgSO4 on maternal cerebral hemodynamics as well as the association between altered Doppler indices of the ophthalmic arteries and ocular lesions in patients with preeclampsia. METHODS: After each of the 15 included patients was diagnosed with preeclampsia, MgSO4 was infused followed by transcranial Doppler tests of the indices of the ophthalmic, anterior, middle, posterior cerebral, vertebral, and basilar arteries, followed by a second MgSO4 infusion. The peak, mean, diastolic velocity, and pulsatile and resistance indices of each artery were automatically measured during testing. Based on the emergent data, the cerebral perfusion pressure, resistance-area product, and cerebral flow index were calculated. RESULTS: The cerebral perfusion pressure of the posterior cerebral arteries significantly decreased following the infusion of MgSO4 (p < 0.05). Before the infusion of MgSO4, cerebral perfusion pressure and cerebral flow index of the ophthalmic arteries were significantly increased (p < 0.05) in the preeclamptic pregnant patients with ocular lesions compared those without ocular lesions. After the infusion of MgSO4, the cerebral perfusion pressure and cerebral flow index of both ophthalmic arteries were slightly decreased, but the difference was not significant. CONCLUSIONS: Altered Doppler indices following the infusion of MgSO4 suggest significant changes in the hemodynamics of the posterior cerebral and ophthalmic arteries that are particularly related to the neurological signs and symptoms of women with preeclampsia. These findings may improve the understanding of the mechanism of the cerebral complications of preeclampsia. Advancing comprehension of these underlying mechanisms is postulated to play a pivotal role in the mitigation of hypertensive encephalopathy associated with preeclampsia.


Assuntos
Circulação Cerebrovascular , Sulfato de Magnésio , Artéria Oftálmica , Pré-Eclâmpsia , Ultrassonografia Doppler Transcraniana , Humanos , Feminino , Pré-Eclâmpsia/fisiopatologia , Pré-Eclâmpsia/tratamento farmacológico , Sulfato de Magnésio/administração & dosagem , Gravidez , Adulto , Artéria Oftálmica/diagnóstico por imagem , Circulação Cerebrovascular/efeitos dos fármacos , Adulto Jovem , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos
19.
Nanoscale ; 16(2): 879-886, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38105661

RESUMO

Mesoporous carbon particles have great potential due to their unique structural properties as support materials for catalytic applications. Particle shapes and channel nanostructures of mesoporous carbon particles can determine the reactant/product transport efficiency. However, the role of the channel nanostructure in the catalytic reaction has not been much explored. Herein, we introduce a facile method to fabricate a series of porous carbon particles (PCPs) with controlled channel exposure on the carbon surface and investigate the impact of the channel nanostructure of the PCPs on the catalytic activity. By employing a membrane emulsification method with a controlled solvent evaporation rate, we fabricate block copolymer (BCP) particles with uniform size and regulated degrees of cylindrical channel exposed to the particle surface. Followed by the carbonization of the BCP particles, a low amount (1.3 wt%) of Pt is incorporated into the PCP series to investigate the impact of channel nanostructures on the catalytic oxidation reaction of o-phenylenediamine (OPD). Specifically, PCP featuring highly open channel nanostructures shows a high reaction rate constant of 0.154 mM-1 s-1 for OPD oxidation, showing 5.5 times higher catalytic activity than those of closed channel nanostructures (0.028 mM-1 s-1). This study provides a deeper understanding of the impact of channel nanostructure within mesoporous carbon particles on catalytic activity.

20.
Commun Chem ; 6(1): 282, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38123721

RESUMO

The direct oxidation of methane to methanol has been spotlighted research for decades, but has never been commercialized. This study introduces cost-effective process for co-producing methanol and sulfuric acid through a direct oxidation of methane. In the initial phase, methane oxidation forms methyl bisulfate (CH3OSO3H), then transformed into methyl trifluoroacetate (CF3CO2CH3) via esterification, and hydrolyzed into methanol. This approach eliminates the need for energy-intensive separation of methyl bisulfate from sulfuric acid by replacing the former with methyl trifluoroacetate. Through the superstructure optimization, our sequential process reduces the levelized cost of methanol to nearly two-fold reduction from the current market price. Importantly, this process demonstrates adaptability to smaller gas fields, assuring its economical operation across a broad range of gas fields. The broader application of this process could substantially mitigate global warming by utilizing methane, leading to a significantly more sustainable and economically beneficial methanol industry.

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