Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 198
Filter
1.
Materials (Basel) ; 17(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38730911

ABSTRACT

Tungsten (W) and W alloys are considered as primary candidates for plasma-facing components (PFCs) that must perform in severe environments in terms of temperature, neutron fluxes, plasma effects, and irradiation bombardment. These materials are notoriously difficult to produce using additive manufacturing (AM) methods due to issues inherent to these techniques. The progress on applying AM techniques to W-based PFC applications is reviewed and the technical issues in selected manufacturing methods are discussed in this review. Specifically, we focus on the recent development and applications of laser powder bed fusion (LPBF), electron beam melting (EBM), and direct energy deposition (DED) in W materials due to their abilities to preserve the properties of W as potential PFCs. Additionally, the existing literature on irradiation effects on W and W alloys is surveyed, with possible solutions to those issues therein addressed. Finally, the gaps in possible future research on additively manufactured W are identified and outlined.

2.
Front Immunol ; 15: 1384516, 2024.
Article in English | MEDLINE | ID: mdl-38765009

ABSTRACT

Viral variant is one known risk factor associated with post-acute sequelae of COVID-19 (PASC), yet the pathogenesis is largely unknown. Here, we studied SARS-CoV-2 Delta variant-induced PASC in K18-hACE2 mice. The virus replicated productively, induced robust inflammatory responses in lung and brain tissues, and caused weight loss and mortality during the acute infection. Longitudinal behavior studies in surviving mice up to 4 months post-acute infection revealed persistent abnormalities in neuropsychiatric state and motor behaviors, while reflex and sensory functions recovered over time. In the brain, no detectable viral RNA and minimal residential immune cell activation was observed in the surviving mice post-acute infection. Transcriptome analysis revealed persistent activation of immune pathways, including humoral responses, complement, and phagocytosis, and gene expression levels associated with ataxia telangiectasia, impaired cognitive function and memory recall, and neuronal dysfunction and degeneration. Furthermore, surviving mice maintained potent systemic T helper 1 prone cellular immune responses and strong sera neutralizing antibodies against Delta and Omicron variants months post-acute infection. Overall, our findings suggest that infection in K18-hACE2 mice recapitulates the persistent clinical symptoms reported in long-COVID patients and provides new insights into the role of systemic and brain residential immune factors in PASC pathogenesis.


Subject(s)
COVID-19 , Disease Models, Animal , Post-Acute COVID-19 Syndrome , SARS-CoV-2 , Animals , COVID-19/immunology , SARS-CoV-2/immunology , Mice , Humans , Brain/virology , Brain/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/blood , Antibodies, Viral/immunology , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Female
3.
Sci Total Environ ; 930: 172729, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38670353

ABSTRACT

Pyruvic acid (PA) is a ubiquitous 2-oxocarboxylic acid in the atmosphere. Its photochemical process at the air-liquid (a-l) interface has been suggested as an important source of aqueous secondary organic aerosols. We investigated the photochemical reaction pathways of PA at the a-l interface using synchrotron-based vacuum ultraviolet single-photon ionization mass spectrometry (VUV SPI-MS) coupled with the System for Analysis at the Liquid Vacuum Interface (SALVI) microreactor. Results from mass spectral analysis and the determination of appearance energies (AEs) indicate that photolysis of PA can generate radicals, then they recombine with carboxylic acids and simple molecular oligomers. Furthermore, the preliminary products could form larger oligomers via radical reaction or esterification in the presence of hydroxyl and carboxyl functional groups. Mass spectral comparison shows that most photochemical reactions would complete within 4 h. The expanded photochemistry-driven reaction flowchart of PA is proposed based on the newly discovered products. Our results reveal that the interfacial PA photochemical reactions have different mechanisms from the bulk liquid due to the interfacial properties, such as molecular density, composition, and ion concentration. Our findings show that in situ mass spectral analysis with bright photon ionization is useful to elucidate the contribution of a-l interfacial reactions leading to aqSOA formation.

4.
Biology (Basel) ; 13(2)2024 Jan 26.
Article in English | MEDLINE | ID: mdl-38392294

ABSTRACT

Adversity stress is the main environmental factor limiting plant growth and development, including salt and other stress factors. This study delves into the adaptability and salt tolerance mechanisms of Machilus faberi Hemsl, a species with potential for cultivation in salinized areas. We subjected the plants to various salt concentrations to observe their growth responses and to assess key physiological and biochemical indicators. The results revealed that under high salt concentrations (500 and 700 mmol-1/L), symptoms such as leaf yellowing, wilting, and eventual death were observed. Notably, plant height and shoot growth ceased on the 14th day of exposure. Chlorophyll content (a, b, total a + b, and the a/b ratio) initially increased but subsequently decreased under varying levels of salt stress. Similarly, the net photosynthetic rate, stomatal conductance, leaf water content, and root activity significantly declined under these conditions. Moreover, we observed an increase in malondialdehyde levels and relative conductivity, indicative of cellular damage and stress. The activity of superoxide dismutase and ascorbate peroxidase initially increased and then diminished with prolonged stress, whereas peroxidase activity consistently increased. Levels of proline and soluble protein exhibited an upward trend, contrasting with the fluctuating pattern of soluble sugars, which decreased initially but increased subsequently. In conclusion, M. faberi exhibits a degree of tolerance to salt stress, albeit with growth limitations when concentrations exceed 300 mmol-1/L. These results shed light on the plant's mechanisms of responding to salt stress and provide a theoretical foundation for its cultivation and application in salt-affected regions.

5.
bioRxiv ; 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38260531

ABSTRACT

Viral variant is one known risk factor associated with post-acute sequelae of COVID-19 (PASC), yet the pathogenesis is largely unknown. Here, we studied SARS-CoV-2 Delta variant-induced PASC in K18-hACE2 mice. The virus replicated productively, induced robust inflammatory responses in lung and brain tissues, and caused weight loss and mortality during the acute infection. Longitudinal behavior studies in surviving mice up to 4 months post-acute infection revealed persistent abnormalities in neuropsychiatric state and motor behaviors, while reflex and sensory functions recovered over time. Surviving mice showed no detectable viral RNA in the brain and minimal neuroinflammation post-acute infection. Transcriptome analysis revealed persistent activation of immune pathways, including humoral responses, complement, and phagocytosis, and reduced levels of genes associated with ataxia telangiectasia, impaired cognitive function and memory recall, and neuronal dysfunction and degeneration. Furthermore, surviving mice maintained potent T helper 1 prone cellular immune responses and high neutralizing antibodies against Delta and Omicron variants in the periphery for months post-acute infection. Overall, infection in K18-hACE2 mice recapitulates the persistent clinical symptoms reported in long COVID patients and may be useful for future assessment of the efficacy of vaccines and therapeutics against SARS-CoV-2 variants.

6.
Macromol Rapid Commun ; 45(7): e2300647, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38243849

ABSTRACT

The rise in universal population and accompanying demands have directed toward an exponential surge in the generation of polymeric waste. The estimate predicts that world-wide plastic production will rise to ≈590 million metric tons by 2050, whereas 5000 million more tires will be routinely abandoned by 2030. Handling this waste and its detrimental consequences on the Earth's ecosystem and human health presents a significant challenge. Converting the wastes into carbon-based functional materials viz. activated carbon, graphene, and nanotubes is considered the most scientific and adaptable method. Herein, this world provides an overview of the various sources of polymeric wastes, modes of build-up, impact on the environment, and management approaches. Update on advances and novel modifications made in methodologies for converting diverse types of polymeric wastes into carbon nanomaterials over the last 5 years are given. A remarkable focus is made to comprehend the applications of polymeric waste-derived carbon nanomaterials (PWDCNMs) in the CO2 capture, removal of heavy metal ions, supercapacitor-based energy storage and water splitting with an emphasis on the correlation between PWDCNMs' properties and their performances. This review offers insights into emerging developments in the upcycling of polymeric wastes and their applications in environment and energy.


Subject(s)
Metals, Heavy , Nanostructures , Nanotubes , Humans , Polymers , Ecosystem
7.
Materials (Basel) ; 17(2)2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38276468

ABSTRACT

Secondary Ion Mass Spectrometry (SIMS) is an outstanding technique for Mass Spectral Imaging (MSI) due to its notable advantages, including high sensitivity, selectivity, and high dynamic range. As a result, SIMS has been employed across many domains of science. In this review, we provide an in-depth overview of the fundamental principles underlying SIMS, followed by an account of the recent development of SIMS instruments. The review encompasses various applications of specific SIMS instruments, notably static SIMS with time-of-flight SIMS (ToF-SIMS) as a widely used platform and dynamic SIMS with Nano SIMS and large geometry SIMS as successful instruments. We particularly focus on SIMS utility in microanalysis and imaging of metals and alloys as materials of interest. Additionally, we discuss the challenges in big SIMS data analysis and give examples of machine leaning (ML) and Artificial Intelligence (AI) for effective MSI data analysis. Finally, we recommend the outlook of SIMS development. It is anticipated that in situ and operando SIMS has the potential to significantly enhance the investigation of metals and alloys by enabling real-time examinations of material surfaces and interfaces during dynamic transformations.

8.
Article in English | MEDLINE | ID: mdl-38190298

ABSTRACT

Introduction: Similar proportions of women and men have entered medical school since 2003. However, career advancement and promotion for women continues to be fraught with disparities and inequalities. Building on current literature, this study explores the rates of change of female faculty in faculty ranks over the last 10 years to gain a more comprehensive view of the faculty trends of women in academic medicine. Methods: Using the Faculty Administrative Management Online User System database, counts by gender and faculty rank at each Association of American Medical Colleges (AAMC) academic medical school were obtained. Statistical analysis was done using generalized estimating equations modeling to assess rates of change for each gender from 2012 to 2021. Results: Higher proportions of female faculty are concentrated at the Instructor and Assistant Professor level and lower proportions at the Associate Professor and Professor rank compared to male faculty. Over the study period, female faculty showed increased rate change compared to male faculty of 1.007 (95% confidence interval [CI]: 1.002-1.012) for Associate Professor rank and 1.012 (95% CI: 1.007-1.016) for Professor rank. At the Instructor and Assistant Professor levels, female faculty decreased at a relative rate of 0.980 (95% CI: 0.969-0.990) and 0.995 (95% CI: 0.992-0.997) each year, respectively. Conclusion: Female faculty continue to be concentrated at the junior faculty rank. Rate changes at the senior faculty rank for female faculty have slightly improved over the last 10 years compared to male faculty. However, this improvement is minimal, and work is still needed to achieve true gender equity in academic medicine.

9.
Int J Behav Med ; 31(2): 192-201, 2024 Apr.
Article in English | MEDLINE | ID: mdl-36952218

ABSTRACT

BACKGROUND: This study examined the trends in diabetes medication taking and its association with the incidence of depression in patients with type 2 diabetes (T2D). METHOD: A retrospective cohort of Medicare enrollees with regular care in 2010 was defined from 100% Texas Medicare claims. The impact of medication taking on incident depression was evaluated from 2010 to 2018. Cox proportional hazards regressions were used to estimate the association between medication taking and depression. RESULTS: A total of 72,461 patients with T2D and with regular care were analyzed. Among 60,216 treated patients, the regular medication taking rate slightly increased from 60.8 to 63.2% during the study period. Patients with regular medication taking at baseline had a 9% lower risk of developing depression (hazard ratio [HR]: 0.91, 95% confidence interval [CI]: 0.89-0.94), and the magnitude of the association increased after adjustment of the model for time-varied medication taking (HR: 0.82, 95% CI: 0.79-0.85). The presence of nephropathy had the greatest mediating effect (23.2%) on the association of medication taking and depression. CONCLUSION: We demonstrated a steady but modest increase in regular diabetes medication taking over a 9-year period and a significant relationship between medication taking and incident depression in patients with T2D.


Subject(s)
Diabetes Mellitus, Type 2 , Humans , Aged , United States/epidemiology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/epidemiology , Retrospective Studies , Depression/epidemiology , Depression/complications , Incidence , Medicare , Risk Factors
10.
PLoS Negl Trop Dis ; 17(12): e0011445, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38091346

ABSTRACT

Scrub typhus is a leading cause of febrile illness in endemic countries due to infection with Orientia tsutsugamushi (Ot), a seriously understudied intracellular bacterium. Pulmonary involvement associated with vascular parasitism in patients is common and can develop into life threatening interstitial pneumonia. The diverse antigenicity of Ot genotypes and inter-strain differences in genome content are connected to varied virulence and clinical outcomes; however, detailed studies of strain-related pulmonary immune responses in human patients or small animal models of infection are lacking. In this study, we have used two clinically prevalent bacterial strains (Karp and Gilliam) to reveal cellular immune responses in inflamed lungs and potential biomarkers of disease severity. The results demonstrate that outbred CD-1 mice are highly susceptible to both Karp and Gilliam strains; however, C57BL/6 (B6) mice were susceptible to Karp, but resistant to Gilliam (with self-limiting infection), corresponding to their tissue bacterial burdens and lung pathological changes. Multicolor flow cytometric analyses of perfused B6 mouse lungs revealed robust and sustained influx and activation of innate immune cells (macrophages, neutrophils, and NK cells), followed by CD4+ and CD8+ T cells, during Karp infection, but such responses were greatly attenuated during Gilliam infection. The robust cellular responses in Karp-infected B6 mice positively correlated with significantly early and high levels of serum cytokine/chemokine protein levels (CXCL1, CCL2/3/5, and G-CSF), as well as pulmonary gene expression (Cxcl1/2, Ccl2/3/4, and Ifng). In vitro infection of B6 mouse-derived primary macrophages also revealed bacterial strain-dependent immune gene expression profiles. This study provided the lines of evidence that highlighted differential tissue cellular responses against Karp vs. Gilliam infection, offering a framework for future investigation of Ot strain-related mechanisms of disease pathogenesis vs. infection control.


Subject(s)
Orientia tsutsugamushi , Scrub Typhus , Humans , Mice , Animals , Orientia tsutsugamushi/genetics , Mice, Inbred C57BL , Scrub Typhus/epidemiology , Antibodies , Immunity, Cellular
11.
Plant Dis ; 2023 Nov 03.
Article in English | MEDLINE | ID: mdl-37923979

ABSTRACT

Ampelopsis grossedentata, commonly known as "Vine Tea" and well-recognized for its rich flavonoid content, is mainly distributed in the southern regions of the Yangtze River basin in China. These regions include Hunan, Hubei, Jiangxi, and Guizhou provinces. Vine Tea is mainly consumed as an herbal tea and has garnered attention for its reported health benefits, including antioxidant, anti-inflammatory, anti-tumor, anti-diabetic, and neuroprotective properties. It has been used to alleviate coughs and sore throats (Zhang et al., 2021; Wang et al., 2017; Gao et al., 2009). In the Zhangjiajie region of Hunan province alone, the Vine Tea planting area reached 7,670.5 hectares and produced commercial goods worth 1.417 billion RMB in 2022. In May 2021, leaf margins and veins fading to yellowing mottling, and crumpling of leaf blades in the shape of a boat symptoms were found in ~16% of Vine Tea plants in the Sanjiakuan Township, Yongding District, Zhangjiajie region (29°15'E, 110°30' N) (Figure 1a, b, c). (Figure 1a, b, c). Phytoplasma-like microbial cells (small oval shaped bacterial cells, around 1000 nm in size) were observed in sieve tube cells in the phloem of diseased leaves using transmission electron microscopy. No such cell was observed in the phloem of healthy leaves (Figure 2a, b). To investigate the potential association between phytoplasma and the observed symptoms of the diseased plants, total DNA was isolated from ten diseasedeaves and compared with ten healthy leaves from the same field using SteadyPure Plant Genomic DNA Extraction Kit. The isolated DNAs were analyzed first in a direct PCR using universal phytoplasma primer pair R16mF2/R16mR1 targeting the 16S rRNA gene (Gundersen and Lee 1996) and specific pair rpF1/rpR1 (Lee et al. 1998) targeting the DNA fragment encoding partial ribosomal proteins (rp) L22 (complete) and S3 and S19 (partial). The initial amplified products were used as templates and further amplified by nested PCR respectively with primer pair R16F2n/R16R2 for the 16S rRNA gene (Lee et al. 1998) and the rpF2/rpR2 primer pair for the rp gene (Martini et al. 2007). No amplification was obtained with DNA from healthy leaf samples using any of the four primer pairs. The amplified fragments from diseased leaves by nested PCR were cloned and sequenced (Qingke Biotech, China). The obtained sequences have been deposited in GenBank with accession numbers OR282806 for the 16S rRNA gene and GenBank OR353012 for the rp gene. BLASTn analysis revealed that the partial 16S rRNA gene sequence in our sample shared 99.4% nucleotide sequence identity with 'Candidatus Phytoplasma sp.' (MW364378) and 'Peony yellows phytoplasma' (KY814723) of the 16SrI group. Similarly, our rp gene sequence shared 99.6% nucleotide identity with the rpI group of phytoplasma such as the 'Balsamine virescence phytoplasma' (JN572890) and 'Paulownia witches'-broom phytoplasma' (HM146079). Phylogenetic analysis of the 16S rRNA and rp sequences using MEGA version 7.0 revealed that the phytoplasma strain associated with A. grossedentata yellow leaf syndrome in our study site belonged to the 16SrI (Candidatus Phytoplasma asteris) group of phytoplasma (Figure 3a, b). Using the interactive online phytoplasma classification tool iPhyClassifier (Zhao et al., 2009), virtual restriction fragment length polymorphism (RFLP) analysis of the 16S rRNA gene sequences showed our strain having a distinct RFLP map but was closest to that of the onion yellow phytoplasma 16SrI-B subgroup (GenBank accession number: AP006628), with a similarity coefficient of 0.94 (Figure 4a, b). To confirm phytoplasma transmission, healthy plants were inoculated with three scions of infected plants of A. grossedentata. After 16 days, the new leaves of the inoculated A. grossedentata showed yellow leaf symptoms (Figure 5a, b, c), akin to the symptoms originally observed in the field, and the outer contour of the leaf margin appeared chlorotic. After 26 days, primer pairs R16mF2/R16R1 and R16F2n/R16R2 were used for nested PCR detection of phytoplasma in symptomatic A. grossedentata leaves. Phytoplasma was detected in the first and second leaves of symptomatic branches and leaves while negative control showed no amplification. Sequencing of the amplified fragments showed 100% nucleotide identity to the strain from the grafting source. Our results indicated that the pathogen and the disease can be transmitted by tissue grafting, consistent with the biological characteristics of phytoplasma, and further confirmed that the phytoplasma was the pathogen of yellow leaf syndrome of A. grossedentata. Toour knowledge, this is the first report of phytoplasma of group 16SrI affecting A. grossedentata.

12.
Cell Rep ; 42(11): 113366, 2023 11 28.
Article in English | MEDLINE | ID: mdl-37938974

ABSTRACT

Monoclonal antibodies against the Ebola virus (EBOV) surface glycoprotein are effective treatments for EBOV disease. Antibodies targeting the EBOV glycoprotein (GP) head epitope have potent neutralization and Fc effector function activity and thus are of high interest as therapeutics and for vaccine design. Here we focus on the head-binding antibodies 1A2 and 1D5, which have been identified previously in a longitudinal study of survivors of EBOV infection. 1A2 and 1D5 have the same heavy- and light-chain germlines despite being isolated from different individuals and at different time points after recovery from infection. Cryoelectron microscopy analysis of each antibody in complex with the EBOV surface GP reveals key amino acid substitutions in 1A2 that contribute to greater affinity, improved neutralization potency, and enhanced breadth as well as two strategies for antibody evolution from a common site.


Subject(s)
Ebolavirus , Hemorrhagic Fever, Ebola , Humans , Antibodies, Neutralizing , Antibodies, Viral , Cryoelectron Microscopy , Longitudinal Studies
13.
Front Chem ; 11: 1253685, 2023.
Article in English | MEDLINE | ID: mdl-37867995

ABSTRACT

Detection of per- and polyfluoroalkyl substances (PFASs) is crucial in environmental mitigation and remediation of these persistent pollutants. We demonstrate that time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a viable technique to analyze and identify these substances at parts per trillion (ppt) level in real field samples without complicated sample preparation due to its superior surface sensitivity. Several representative PFAS compounds, such as perfluorooctanesulfonic acid (PFOS), perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluoheptanoic acid (PFHpA), and perfluorononanoic acid (PFNA), and real-world groundwater samples collected from monitoring wells installed around at a municipal wastewater treatment plant located in Southern California were analyzed in this work. ToF-SIMS spectral comparison depicts sensitive identification of pseudo-molecular ions, characteristic of reference PFASs. Additionally, principal component analysis (PCA) shows clear discrimination among real samples and reference compounds. Our results show that characteristic molecular ion and fragments peaks can be used to identify PFASs. Furthermore, SIMS two-dimensional (2D) images directly exhibit the distribution of perfluorocarboxylic acid (PFCA) and PFOS in simulated mixtures and real wastewater samples. Such findings indicate that ToF-SIMS is useable to determine PFAS compounds in complex environmental water samples. In conclusion, ToF-SIMS provides simple sample preparation and high sensitivity in mass spectral imaging, offering an alternative solution for environmental forensic analysis of PFASs in wastewater in the future.

14.
Plants (Basel) ; 12(19)2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37836132

ABSTRACT

The basic helix-loop-helix (bHLH) transcription factor family is the second-largest transcription factor family in plants. Members of this family are involved in the processes of growth and development, secondary metabolic biosynthesis, signal transduction, and plant resistance. Loropetalum chinense var. rubrum is a critical woody plant with higher ornamental and economic values, which has been used as ornamental architecture and traditional Chinese herbal medicine plants. However, the bHLH transcription factors in Loropetalum chinense var. rubrum (L. chinense var. rubrum) have not yet been systematically demonstrated, and their role in the biosynthesis of anthocyanin is still unclear. Here, we identified 165 potential LcbHLHs genes by using two methods, and they were unequally distributed on chromosomes 1 to 12 of the genome of L. chinense var. rubrum. Based on an evolutionary comparison with proteins from Arabidopsis and Oryza sativa, these bHLH proteins were categorized into 21 subfamilies. Most LcbHLHs in a particular subfamily had similar gene structures and conserved motifs. The Gene Ontology annotation and Cis-elements predicted that LcbHLHs had many molecular functions and were involved in processes of plant growth, including the biosynthesis of flavonoids and anthocyanins. Transcriptomic analysis revealed different expression patterns among different tissues and cultivars of L. chinense var. rubrum. Many LcbHLHs were expressed in the leaves, and only a few genes were highly expressed in the flowers. Six LcbHLHs candidate genes were identified by bioinformatics analysis and expression analysis. Further Real-time quantitative PCR analysis and protein interaction network analysis showed that LcbHLH156, which is one of the candidate proteins belonging to the IIIf subfamily, could interact with proteins related to anthocyanin synthesis. Therefore, LcbHLH156 was transiently expressed in L. chinense var. rubrum to verify its function in regulating anthocyanin synthesis. Compared with the control group, red pigment accumulation appeared at the wound after injection, and the total anthocyanin content increased at the wound of leaves. These results lay a foundation for the research of the regulation mechanism of leaf colors in L. chinense var. rubrum and also provide a basis for the function of the LcbHLH family.

15.
ACS Energy Lett ; 8(10): 3999-4007, 2023 Oct 13.
Article in English | MEDLINE | ID: mdl-37854047

ABSTRACT

Reversible proton-conducting solid oxide cells (R-PSOCs) have the potential to be the most efficient and cost-effective electrochemical device for energy storage and conversion. A breakthrough in air electrode material development is vital to minimizing the energy loss and degradation of R-PSOCs. Here we report a class of triple-conducting air electrode materials by judiciously doping transition- and rare-earth metal ions into a proton-conducting electrolyte material, which demonstrate outstanding activity and durability for R-PSOC applications. The optimized composition Ba0.9Pr0.1Hf0.1Y0.1Co0.8O3-δ (BPHYC) consists of three phases, which have a synergistic effect on enhancing the performance, as revealed from electrochemical analysis and theoretical calculations. When applied to R-PSOCs operated at 600 °C, a peak power density of 1.37 W cm-2 is demonstrated in the fuel cell mode, and a current density of 2.40 A cm-2 is achieved at a cell voltage of 1.3 V in the water electrolysis mode under stable operation for hundreds of hours.

16.
Fa Yi Xue Za Zhi ; 39(4): 382-387, 2023 Aug 25.
Article in English, Chinese | MEDLINE | ID: mdl-37859477

ABSTRACT

OBJECTIVES: To study the virtual reality-pattern visual evoked potential (VR-PVEP) P100 waveform characteristics of monocular visual impairment with different impaired degrees under simultaneous binocular perception and monocular stimulations. METHODS: A total of 55 young volunteers with normal vision (using decimal recording method, far vision ≥0.8 and near vision ≥0.5) were selected to simulate three groups of monocular refractive visual impairment by interpolation method. The sum of near and far vision ≤0.2 was Group A, the severe visual impairment group; the sum of near and far vision <0.8 was Group B, the moderate visual impairment group; and the sum of near and far vision ≥0.8 was Group C, the mild visual impairment group. The volunteers' binocular normal visions were set as the control group. The VR-PVEP P100 peak times measured by simultaneous binocular perception and monocular stimulation were compared at four spatial frequencies 16×16, 24×24, 32×32 and 64×64. RESULTS: In Group A, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 24×24, 32×32 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group B, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 16×16, 24×24 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group C, there was no significant difference between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at all spatial frequencies (P>0.05). There was no significant difference in the P100 peak times measured at all spatial frequencies between simulant visual impairment eyes and simultaneous binocular perception in the control group (P>0.05). CONCLUSIONS: VR-PVEP can be used for visual acuity evaluation of patients with severe and moderate monocular visual impairment, which can reflect the visual impairment degree caused by ametropia. VR-PVEP has application value in the objective evaluation of visual function and forensic clinical identification.


Subject(s)
Evoked Potentials, Visual , Virtual Reality , Humans , Vision, Ocular , Vision, Binocular/physiology , Vision Disorders/diagnosis
17.
Micromachines (Basel) ; 14(9)2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37763890

ABSTRACT

Understanding the corrosion of spent nuclear fuel is important for the development of long-term storage solutions. However, the risk of radiation contamination presents challenges for experimental analysis. Adapted from the system for analysis at the liquid-vacuum interface (SALVI), we developed a miniaturized uranium oxide (UO2)-attached working electrode (WE) to reduce contamination risk. To protect UO2 particles in a miniatured electrochemical cell, a thin layer of Nafion was formed on the surface. Atomic force microscopy (AFM) shows a dense layer of UO2 particles and indicates their participation in electrochemical reactions. Particles remain intact on the electrode surface with slight redistribution. X-ray photoelectron spectroscopy (XPS) reveals a difference in the distribution of U(IV), U(V), and U(VI) between pristine and corroded UO2 electrodes. The presence of U(V)/U(VI) on the corroded electrode surface demonstrates that electrochemically driven UO2 oxidation can be studied using these cells. Our observations of U(V) in the micro-electrode due to the selective semi-permeability of Nafion suggest that interfacial water plays a key role, potentially simulating a water-lean scenario in fuel storage conditions. This novel approach offers analytical reproducibility, design flexibility, a small footprint, and a low irradiation dose, while separating the α-effect. This approach provides a valuable microscale electrochemical platform for spent fuel corrosion studies with minimal radiological materials and the potential for diverse configurations.

18.
Int J Clin Exp Pathol ; 16(7): 150-157, 2023.
Article in English | MEDLINE | ID: mdl-37559684

ABSTRACT

OBJECTIVE: Folic acid (FA) may contribute to the development of gestational diabetes mellitus (GDM), but available studies are inconsistent. We studied the genotype distribution and allele frequencies of methylenetetrahydrofolate reductase (MTHFR) C677T, A1298C, and methionine synthase reductase (MTRR) A66G polymorphisms in pregnant Chinese women and compared the effects of individualized and traditional FA supplementation on GDM. METHODS: In this retrospective study, genotype distribution and allele frequencies in 968 pregnant women were tested. FA metabolism was tested by dividing patients into four groups, each of which was supplemented with different doses of FA at different times. Pregnancy complications were followed up and compared to 1940 pregnant women traditionally supplemented with FA in the same hospital as a control group. RESULTS: The allele frequencies were 63.3% (C) and 36.7% (T) for MTHFR C677T, 79.3% (A) and 20.7% (C) for MTHFR A1298C and 75.0% (A) and 25.0% (G) for MTRR A66G. The incidence of GDM after FA supplementation was significantly lower in the case group compared to the control group, especially in high-risk pregnancies. CONCLUSION: Using genetic polymorphisms to elucidate FA metabolism in pregnant women and providing appropriate FA supplementation can be effective in reducing GDM, especially in high-risk groups.

19.
Microorganisms ; 11(8)2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37630605

ABSTRACT

Plant-microbe interactions are of rising interest in plant sustainability, biomass production, plant biology, and systems biology. These interactions have been a challenge to detect until recent advancements in mass spectrometry imaging. Plants and microbes interact in four main regions within the plant, the rhizosphere, endosphere, phyllosphere, and spermosphere. This mini review covers the challenges within investigations of plant and microbe interactions. We highlight the importance of sample preparation and comparisons among time-of-flight secondary ion mass spectroscopy (ToF-SIMS), matrix-assisted laser desorption/ionization (MALDI), laser desorption ionization (LDI/LDPI), and desorption electrospray ionization (DESI) techniques used for the analysis of these interactions. Using mass spectral imaging (MSI) to study plants and microbes offers advantages in understanding microbe and host interactions at the molecular level with single-cell and community communication information. More research utilizing MSI has emerged in the past several years. We first introduce the principles of major MSI techniques that have been employed in the research of microorganisms. An overview of proper sample preparation methods is offered as a prerequisite for successful MSI analysis. Traditionally, dried or cryogenically prepared, frozen samples have been used; however, they do not provide a true representation of the bacterial biofilms compared to living cell analysis and chemical imaging. New developments such as microfluidic devices that can be used under a vacuum are highly desirable for the application of MSI techniques, such as ToF-SIMS, because they have a subcellular spatial resolution to map and image plant and microbe interactions, including the potential to elucidate metabolic pathways and cell-to-cell interactions. Promising results due to recent MSI advancements in the past five years are selected and highlighted. The latest developments utilizing machine learning are captured as an important outlook for maximal output using MSI to study microorganisms.

SELECTION OF CITATIONS
SEARCH DETAIL
...