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1.
Nature ; 626(8001): 1005-1010, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38418918

RESUMEN

Heterogeneous catalysts are widely used to promote chemical reactions. Although it is known that chemical reactions usually happen on catalyst surfaces, only specific surface sites have high catalytic activity. Thus, identifying active sites and maximizing their presence lies at the heart of catalysis research1-4, in which the classic model is to categorize active sites in terms of distinct surface motifs, such as terraces and steps1,5-10. However, such a simple categorization often leads to orders of magnitude errors in catalyst activity predictions and qualitative uncertainties of active sites7,8,11,12, thus limiting opportunities for catalyst design. Here, using stepped Pt(111) surfaces and the electrochemical oxygen reduction reaction (ORR) as examples, we demonstrate that the root cause of larger errors and uncertainties is a simplified categorization that overlooks atomic site-specific reactivity driven by surface stress release. Specifically, surface stress release at steps introduces inhomogeneous strain fields, with up to 5.5% compression, leading to distinct electronic structures and reactivity for terrace atoms with identical local coordination, and resulting in atomic site-specific enhancement of ORR activity. For the terrace atoms flanking both sides of the step edge, the enhancement is up to 50 times higher than that of the atoms in the middle of the terrace, which permits control of ORR reactivity by either varying terrace widths or controlling external stress. Thus, the discovery of the above synergy provides a new perspective for both fundamental understanding of catalytically active atomic sites and design principles of heterogeneous catalysts.

2.
Nano Lett ; 23(15): 6839-6844, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37463412

RESUMEN

Longevity of Li ion batteries strongly depends on the interaction of transporting Li ions in electrode crystals with defects. However, detailed interactions between the Li ion flux and structural defects in the host crystal remain obscure due to the transient nature of such interactions. Here, by in situ transmission electron microscopy and density function theory calculations, we reveal how the diffusion pathways and transport kinetics of a Li ion can be affected by planar defects in a tungsten trioxide lattice. We uncover that changes in charge distribution and lattice spacing along the planar defects disrupt the continuity of ion conduction channels and dramatically increase the energy barrier of Li diffusion, thus, arresting Li ions at the defect sites and twisting the lithiation front. The atomic-scale understanding holds critical implications for rational interface design in solid-state batteries and solid oxide fuel cells.

3.
BMC Geriatr ; 23(1): 796, 2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-38049752

RESUMEN

OBJECTIVE: This study, based on the China Hainan Centenarians Cohort Study (CHCCS), aims to comprehensively describe the characteristic of daytime, night and total sleep duration, sleep quality and different sleep mode of Hainan centenarians and their associations with activity of daily living (ADL) functions. METHOD: The baseline data of CHCCS was used. ADL function was evaluated the Bathel index, sleep quality was evaluated by Pittsburgh sleep quality index (PSQI), sleep status including daytime, night and total sleep duration as well as sleep quality and sleep mode. Multivariate logistic regression model was used to explore the association between sleep status and ADL disability and ADL moderate & severe disability. RESULTS: A total of 994 centenarians were included in this study with the age range 100-116 years old. Compared with the centenarians who sleep 6-9 h at night and < 2 h in the daytime, the adjusted OR between sleep > 9 h at night and sleep ≥ 2 h in the daytime and ADL disability was 2.93 (95% CI: 1.02-8.44), and adjusted OR of ADL moderate & severe disability was 2.75 (95% CI: 1.56-4.83). Compared with centenarians who sleep for 7-9 h and have good sleep quality, centenarians who sleep for > 9 h and have poor sleep quality have an increased risk of ADL moderate & severe disability (OR = 3.72, 95% CI: 1.54-9.00). CONCLUSION: Relation between sleep duration and ADL disability was more significant compared with sleep quality in Hainan centenarians. Poor sleep quality can aggravate the relationship between sleep duration and ADL moderate & severe disability.


Asunto(s)
Centenarios , Trastornos del Inicio y del Mantenimiento del Sueño , Anciano de 80 o más Años , Humanos , Actividades Cotidianas , Estudios de Cohortes , Sueño , China/epidemiología
4.
Gen Physiol Biophys ; 42(2): 191-199, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36896948

RESUMEN

Long non-coding RNAs (lncRNAs) are involved in the development of myocardial ischemia/reperfusion injury (MIRI). In this study, we aimed to explore the regulatory effect and mechanism of lncRNA SOX2-overlapping transcript (SOX2-OT) in MIRI. The viability of oxygen and glucose deprivation/reperfusion (OGD/R)-treated H9c2 cells was detected by MTT assay. The levels of interleukin (IL)-1ß, IL-6, tumor necrosis factor (TNF)-α, malondialdehyde (MDA), and superoxide dismutase (SOD) were measured by ELISA. The target relationship between SOX2-OT and miR-146a-5p was predicted by LncBase, and subsequently confirmed by Dual luciferase reporter assay. The effects of SOX2-OT silencing on myocardial apoptosis and function were further validated in MIRI rats. The expression of SOX2-OT was increased in OGD/R-treated H9c2 cells and myocardial tissues of MIRI rats. Silencing of SOX2-OT increased the viability and inhibited the inflammation and oxidative stress of OGD/R-treated H9c2 cells. SOX2-OT negatively regulated its target miR-146a-5p. Silencing of miR-146a-5p reversed the effects of sh-SOX2-OT on OGD/R-treated H9c2 cells. In addition, silencing of SOX2-OT also alleviated myocardial apoptosis and improved myocardial function in MIRI rats. Silencing of SOX2-OT relieved the apoptosis, inflammation, and oxidative stress of myocardial cells via up-regulating miR-146a-5p, contributing to the remission of MIRI.


Asunto(s)
MicroARNs , Daño por Reperfusión Miocárdica , ARN Largo no Codificante , Ratas , Animales , Daño por Reperfusión Miocárdica/genética , ARN Largo no Codificante/genética , MicroARNs/genética , MicroARNs/metabolismo , Células Cultivadas , Apoptosis/genética , Inflamación , Glucosa , Oxígeno
5.
Int J Mol Sci ; 24(10)2023 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-37239960

RESUMEN

The degeneration of midbrain dopaminergic (mDA) neurons, particularly in the substantia nigra pars compacta (SNc), is one of the most prominent pathological hallmarks of Parkinson's disease (PD). To uncover the pathogenic mechanisms of mDA neuronal death during PD may provide therapeutic targets to prevent mDA neuronal loss and slow down the disease's progression. Paired-like homeodomain transcription factor 3 (Pitx3) is selectively expressed in the mDA neurons as early as embryonic day 11.5 and plays a critical role in mDA neuron terminal differentiation and subset specification. Moreover, Pitx3-deficient mice exhibit some canonical PD-related features, including the profound loss of SNc mDA neurons, a dramatic decrease in striatal dopamine (DA) levels, and motor abnormalities. However, the precise role of Pitx3 in progressive PD and how this gene contributes to mDA neuronal specification during early stages remains unclear. In this review, we updated the latest findings on Pitx3 by summarizing the crosstalk between Pitx3 and its associated transcription factors in mDA neuron development. We further explored the potential benefits of Pitx3 as a therapeutic target for PD in the future. To better understand the transcriptional network of Pitx3 in mDA neuron development may provide insights into Pitx3-related clinical drug-targeting research and therapeutic approaches.


Asunto(s)
Neuronas Dopaminérgicas , Proteínas de Homeodominio , Enfermedad de Parkinson , Factores de Transcripción , Animales , Ratones , Dopamina , Neuronas Dopaminérgicas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Mesencéfalo/metabolismo , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/patología , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
6.
Bratisl Lek Listy ; 124(2): 143-150, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36598302

RESUMEN

PURPOSE: Long noncoding RNAs (lncRNAs) are involved in the development of myocardial ischemia/reperfusion injury (MIRI). In this study, we aimed to explore the regulatory effect and mechanism of lncRNA SOX2-OT in MIRI. METHODS: The expression levels of SOX2-OT and miR-146a-5p in OGD/R-treated H9C2 cells and in myocardial tissues of MIRI rats were measured by qRT-PCR. Cell viability was detected by MTT assay. The levels of IL-1ß, IL-6, TNF-α, MDA, and SOD were measured by ELISA. The target relationship between SOX2-OT and miR-146a-5p was predicted by LncBase, and subsequently confirmed by DLR assay. The effects of SOX2-OT silencing on myocardial apoptosis and function were further validated in MIRI rats. RESULTS: The expression of SOX2-OT was increased in OGD/R-treated H9C2 cells and myocardial tissues of MIRI rats. Silencing of SOX2-OT increased the viability and inhibited the inflammation and oxidative stress of OGD/R-treated H9C2 cells. SOX2-OT negatively regulated its target miR-146a-5p. Inhibition of miR-146a-5p reversed the effects of sh-SOX2-OT on increasing the viability, and on inhibiting the inflammation and oxidative stress of OGD/R-treated H9C2 cells. In addition, silencing of SOX2-OT alleviated myocardial apoptosis and improved myocardial function in MIRI rats. CONCLUSIONS: Silencing of SOX2-OT relieved the apoptosis, inflammation, and oxidative stress of myocardial cells via up-regulating miR-146a-5p, contributing to the remission of MIRI (Fig. 28, Ref. 33).


Asunto(s)
MicroARNs , Daño por Reperfusión Miocárdica , ARN Largo no Codificante , Animales , Ratas , Apoptosis/genética , Inflamación , MicroARNs/genética , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Transducción de Señal
7.
Nano Lett ; 21(16): 6875-6881, 2021 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-34387995

RESUMEN

Electrochemical cycling induces transition-metal (TM) ion migration and oxygen vacancy formation in layered transition-metal oxides, thus causing performance decay. Here, a combination of ab initio calculations and atomic level imaging is used to explore the TM migration mechanisms in LiNi1/3Mn1/3Co1/3O2 (NMC333). For the bulk model, TM/Li exchange is an favorable energy pathway for TM migration. For the surface region with the presence of oxygen vacancies, TM condensation via substitution of Li vacancies (TMsub) deciphers the frequently observed TM segregation phenomena in the surface region. Ni migrates much more easily in both the bulk and surface regions, highlighting the critical role of Ni in stabilizing layered cathodes. Moreover, once TM ions migrate to the Li layer, it is easier for TM ions to diffuse and form a TM-enriched surface layer. The present study provides vital insights into the potential paths to tailor layered cathodes with a high structural stability and superior performance.


Asunto(s)
Suministros de Energía Eléctrica , Litio , Electrodos , Óxidos , Oxígeno
8.
BMC Genomics ; 22(1): 722, 2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34615480

RESUMEN

BACKGROUND: Glioma is the most common central nervous system tumor with a poor survival rate and prognosis. Previous studies have found that long non-coding RNA (lncRNA) and competitive endogenous RNA (ceRNA) play important roles in regulating various tumor mechanisms. We obtained RNA-Seq data of glioma and normal brain tissue samples from TCGA and GTEx databases and extracted the lncRNA and mRNA expression data. Further, we analyzed these data using weighted gene co-expression network analysis and differential expression analysis, respectively. Differential expression analysis was also carried out on the mRNA data from the GEO database. Further, we predicted the interactions between lncRNA, miRNA, and targeted mRNA. Using the CGGA data to perform univariate and multivariate Cox regression analysis on mRNA. RESULTS: We constructed a Cox proportional hazard regression model containing four mRNAs and performed immune infiltration analysis. Moreover, we also constructed a ceRNA network including 21 lncRNAs, two miRNAs, and four mRNAs, and identified seven lncRNAs related to survival that have not been previously studied in gliomas. Through the gene set enrichment analysis, we found four lncRNAs that may have a significant role in tumors and should be explored further in the context of gliomas. CONCLUSIONS: In short, we identified four lncRNAs with research value for gliomas, constructed a ceRNA network in gliomas, and developed a prognostic prediction model. Our research enhances our understanding of the molecular mechanisms underlying gliomas, providing new insights for developing targeted therapies and efficiently evaluating the prognosis of gliomas.


Asunto(s)
Glioma , Glioma/genética , Humanos
9.
BMC Cancer ; 21(1): 98, 2021 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-33499813

RESUMEN

BACKGROUND: Long intergenic non-coding RNAs (lincRNAs) are capable of regulating several tumours, while competitive endogenous RNA (ceRNA) networks are of great significance in revealing the biological mechanism of tumours. Here, we aimed to study the ceRNA network of lincRNA in glioblastoma (GBM). METHODS: We obtained GBM and normal brain tissue samples from TCGA, GTEx, and GEO databases, and performed weighted gene co-expression network analysis and differential expression analysis on all lincRNA and mRNA data. Subsequently, we predicted the interaction between lincRNAs, miRNAs, and target mRNAs. Univariate and multivariate Cox regression analyses were performed on the mRNAs using CGGA data, and a Cox proportional hazards regression model was constructed. The ceRNA network was further screened by the DEmiRNA and mRNA of Cox model. RESULTS: A prognostic prediction model was constructed for patients with GBM. We assembled a ceRNA network consisting of 18 lincRNAs, 6 miRNAs, and 8 mRNAs. Gene Set Enrichment Analysis was carried out on four lincRNAs with obvious differential expressions and relatively few studies in GBM. CONCLUSION: We identified four lincRNAs that have research value for GBM and obtained the ceRNA network. Our research is expected to facilitate in-depth understanding and study of the molecular mechanism of GBM, and provide new insights into targeted therapy and prognosis of the tumour.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Glioblastoma/patología , MicroARNs/genética , ARN Largo no Codificante/genética , ARN Mensajero/metabolismo , Biomarcadores de Tumor/genética , Estudios de Seguimiento , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Pronóstico , ARN Mensajero/genética , Estudios Retrospectivos , Programas Informáticos , Tasa de Supervivencia
10.
Fish Shellfish Immunol ; 104: 419-430, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32562868

RESUMEN

The liver-expressed antimicrobial peptide-2 (LEAP-2) is an important component of the innate immune defense system and plays an important role in resisting the invasion of pathogenic microorganisms. In this study, LEAP-2 from golden pompano (Trachinotus ovatus) was characterized and its expression in response to Photobacterium damselae was investigated. The full-length LEAP-2 cDNA was 1758 bp, which comprised a 5'-UTR of 250 bp, an ORF of 321 bp, and a 3'-UTR of 1187 bp, encoding 106 amino acids. LEAP-2 consisted of a conserved saposin B domain and four conserved cysteines that formed two pairs of disulphide bonds. The genomic organization of LEAP-2 was also determined and shown to consisted of three introns and two exons. The predicted promoter region of ToLEAP-2 contained several putative transcription factor binding sites. Quantitative real-time (qRT-PCR) analysis indicated that LEAP-2 was ubiquitously expressed in all examined tissues, with higher mRNA levels observed in the muscle, liver, spleen, and kidney. After P. damselae stimulation, the expression level of LEAP-2 mRNA was significantly upregulated in various tissues of golden pompano. In addition, SDS-PAGE showed that the molecular mass of recombinant LEAP-2 expressed in pET-32a was approximately 23 kDa. The purified recombinant protein showed antibacterial activity against Gram-positive and Gram-negative bacteria. Luciferase reporters were constructed for five deletion fragments of different lengths from the promoter region (-1575 bp to +251 bp), and the results showed that L3 (-659 bp to +251 bp) presented the highest activity, and it was therefore defined as the core region of the LEAP-2 promoter. The seven predicted transcription factor binding sites were deleted by using PCR technology, and the results showed that the mutation of the USF transcription factor binding site caused the activity to significantly decrease. The results indicate that golden pompano LEAP-2 potentially exhibits antimicrobial effects in fish innate immunity.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/genética , Péptidos Catiónicos Antimicrobianos/inmunología , Enfermedades de los Peces/inmunología , Peces/genética , Peces/inmunología , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos/química , Secuencia de Bases , Proteínas de Peces/química , Proteínas de Peces/genética , Proteínas de Peces/inmunología , Perfilación de la Expresión Génica/veterinaria , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/fisiología , Filogenia , Alineación de Secuencia/veterinaria
11.
Dis Aquat Organ ; 137(3): 195-204, 2020 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-31942865

RESUMEN

Golden pompano Trachinotus ovatus (Linnaeus, 1758) is an important mariculture fish species with high commercial value in China. The present study thoroughly assessed the types and frequencies of skeletal deformities at the early developmental stages of golden pompano in an intensive aquaculture production system. Golden pompano (n = 500) were sampled 30 d posthatch (dph). The specimens were stained with Alcian blue and Alizarin red for the detection of deformities. The results of the study revealed that 77.2% of the specimens showed at least 1 spinal anomaly; most anomalies occurred in the prehemal region, and the most common deformity observed was vertebral fusion (37.4% incidence of deformities). The results of this study provide useful information for the early detection of skeletal deformities and for the optimization of fish fry breeding technologies.


Asunto(s)
Enfermedades de los Peces , Perciformes , Animales , Acuicultura , China , Peces
12.
Sensors (Basel) ; 18(8)2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-30126164

RESUMEN

Grooving is widely used to improve airport runway pavement skid resistance during wet weather. However, runway grooves deteriorate over time due to the combined effects of traffic loading, climate, and weather, which brings about a potential safety risk at the time of the aircraft takeoff and landing. Accordingly, periodic measurement and evaluation of groove performance are critical for runways to maintain adequate skid resistance. Nevertheless, such evaluation is difficult to implement due to the lack of sufficient technologies to identify shallow or worn grooves and slab joints. This paper proposes a new strategy to automatically identify airport runway grooves and slab joints using high resolution laser profiling data. First, K-means clustering based filter and moving window traversal algorithm are developed to locate the deepest point of the potential dips (including noises, true grooves, and slab joints). Subsequently the improved moving average filter and traversal algorithms are used to determine the left and right endpoint positions of each identified dip. Finally, the modified heuristic method is used to separate out slab joints from the identified dips, and then the polynomial support vector machine is introduced to distinguish out noises from the candidate grooves (including noises and true grooves), so that PCC slab-based runway safety evaluation can be performed. The performance of the proposed strategy is compared with that of the other two methods, and findings indicate that the new method is more powerful in runway groove and joint identification, with the F-measure score of 0.98. This study would be beneficial in airport runway groove safety evaluation and the subsequent maintenance and rehabilitation of airport runway.

13.
Redox Biol ; 70: 103006, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38241837

RESUMEN

Alzheimer's disease (AD) is the most common neurodegenerative disorder with the pathological hallmarks of amyloid beta (Aß) plaques and neurofibrillary tangles (NFTs) in the brain. Although there is a hope that anti-amyloid monoclonal antibodies may emerge as a new therapy for AD, the high cost and side effect is a big concern. Non-drug therapy is attracting more attention and may provide a better resolution for the treatment of AD. Given the fact that hypoxia contributes to the pathogenesis of AD, hyperbaric oxygen therapy (HBOT) may be an effective intervention that can alleviate hypoxia and improve AD. However, it remains unclear whether long-term HBOT intervention in the early stage of AD can slow AD progression and ultimately prevent cognitive impairment in this disease. In this study we applied consecutive 3-month HBOT interventions on 3-month-old APPswe/PS1dE9 AD mice which represent the early stage of AD. When the APPswe/PS1dE9 mice at 9-month-old which represent the disease stage we measured cognitive function, 24-h blood oxygen saturation, Aß and tau pathologies, vascular structure and function, and neuroinflammation in APPswe/PS1dE9 mice. Our results showed that long-term HBOT can attenuate the impairments in cognitive function observed in 9-month-old APPswe/PS1dE9 mice. Most importantly, HBOT effectively reduced the progression of Aß plaques deposition, hyperphosphorylated tau protein aggregation, and neuronal and synaptic degeneration in the AD mice. Further, long-term HBOT was able to enhance blood oxygen saturation level. Besides, long-term HBOT can improve vascular structure and function, and reduce neuroinflammation in AD mice. This study is the first to demonstrate that long-term HBOT intervention in the early stage of AD can attenuate cognitive impairment and AD-like pathologies. Overall, these findings highlight the potential of long-term HBOT as a disease-modifying approach for AD treatment.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Ratones , Animales , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Enfermedades Neuroinflamatorias , Ratones Transgénicos , Disfunción Cognitiva/etiología , Disfunción Cognitiva/terapia , Hipoxia/complicaciones , Modelos Animales de Enfermedad
14.
Artículo en Inglés | MEDLINE | ID: mdl-38150001

RESUMEN

OBJECTIVES: This study aimed to analyze the association between sleep quality, sleep duration, and cognitive functions among centenarians. METHODS: The baseline data of the China Hainan Centenarians Cohort Study served as the foundation for this study. Logistic regression was utilized to demonstrate the relationship between sleep status and cognitive impairment. Moreover, a canonical correlation analysis was performed to analyze the correlation between these variables. RESULTS: A total of 994 centenarians were included. After adjustment, poor sleep quality centenarians had an odds ratio of 1.77 (95% confidence interval [CI]: 1.00-3.09) for cognitive impairment when compared to centenarians with normal sleep quality. Centenarians who slept for more than 9 hr had a stronger association with severe cognitive impairment, indicated by an odds ratio of 1.41 (95% CI: 1.02-1.96), compared to those who slept for 7-9 hr. Additionally, the canonical correlation analysis results revealed that the linear combination of sleep quality V1, primarily determined by sleep latency, daytime dysfunction, and subjective sleep quality, was associated with cognitive function; the linear combination of cognitive function W1, mainly determined by orientation, attention and calculation, and memory. DISCUSSION: There exists a correlation between poor sleep quality and cognitive impairment in centenarians, as well as a correlation between sleep duration >9 hr at night and severe cognitive impairment. The primary cognitive domains associated with sleep quality are orientation, calculation, and memory. It is imperative to monitor and safeguard the cognitive functions linked to poor sleep quality in the older individuals, with attention to orientation, calculation, and memory.


Asunto(s)
Centenarios , Disfunción Cognitiva , Anciano de 80 o más Años , Humanos , Estudios de Cohortes , Sueño , Disfunción Cognitiva/epidemiología , Cognición
15.
J Geophys Res Space Phys ; 128(2): e2022JA030835, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37035843

RESUMEN

Current inference techniques for processing multi-needle Langmuir probe (m-NLP) data are often based on adaptations of the Orbital Motion-Limited (OML) theory which relies on several simplifying assumptions. Some of these assumptions, however, are typically not well satisfied in actual experimental conditions, thus leading to uncontrolled uncertainties in inferred plasma parameters. In order to remedy this difficulty, three-dimensional kinetic particle in cell simulations are used to construct a synthetic data set, which is used to compare and assess different m-NLP inference techniques. Using a synthetic data set, regression-based models capable of inferring electron density and satellite potentials from 4-tuples of currents collected with fixed-bias needle probes similar to those on the NorSat-1 satellite, are trained and validated. The regression techniques presented show promising results for plasma density inferences with RMS relative errors less than 20%, and satellite potential inferences with RMS errors less than 0.2 V for potentials ranging from -6 to -1 V. The new inference approaches presented are applied to NorSat-1 data, and compared with existing state-of-the-art inference techniques.

16.
Redox Biol ; 68: 102955, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37956598

RESUMEN

Oxygen metabolism abnormality plays a crucial role in the pathogenesis of Alzheimer's disease (AD) via several mechanisms, including hypoxia, oxidative stress, and mitochondrial dysfunction. Hypoxia condition usually results from living in a high-altitude habitat, cardiovascular and cerebrovascular diseases, and chronic obstructive sleep apnea. Chronic hypoxia has been identified as a significant risk factor for AD, showing an aggravation of various pathological components of AD, such as amyloid ß-protein (Aß) metabolism, tau phosphorylation, mitochondrial dysfunction, and neuroinflammation. It is known that hypoxia and excessive hyperoxia can both result in oxidative stress and mitochondrial dysfunction. Oxidative stress and mitochondrial dysfunction can increase Aß and tau phosphorylation, and Aß and tau proteins can lead to redox imbalance, thus forming a vicious cycle and exacerbating AD pathology. Hyperbaric oxygen therapy (HBOT) is a non-invasive intervention known for its capacity to significantly enhance cerebral oxygenation levels, which can significantly attenuate Aß aggregation, tau phosphorylation, and neuroinflammation. However, further investigation is imperative to determine the optimal oxygen pressure, duration of exposure, and frequency of HBOT sessions. In this review, we explore the prospects of oxygen metabolism in AD, with the aim of enhancing our understanding of the underlying molecular mechanisms in AD. Current research aimed at attenuating abnormalities in oxygen metabolism holds promise for providing novel therapeutic approaches for AD.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/terapia , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Oxígeno , Enfermedades Neuroinflamatorias , Proteínas tau/metabolismo , Hipoxia
17.
J Phys Chem Lett ; 14(47): 10537-10544, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-37972416

RESUMEN

Heteroatom incorporation can effectively suppress the phase transition of layered sodium-ion battery cathode, but heteroatom behaviors during operating conditions are not completely understood at the atomic scale. Here, density functional theory calculations are combined with experiments to explore the mitigation behavior of Mg dopant and its mechanisms under operating conditions in P2-Na0.67Ni0.33Mn0.67O2. The void formed by Na extraction will pump some Mg dopants into Na layers from TM layers, and the collective diffusion of more than one Mg ion most likely occurs when the Mg content is relatively high in the TM layer, finally aggregating to form Mg-enrich regions (i.e., Mg segregation) apart from Ni vacancies. The void-pump-effect-induced Mg segregation effectively suppresses the P2-O2 phase transition owing to the stronger Mg-O electrostatic attraction that enhances the integrate of two adjacent oxygen layers and prevents the crack growth by mitigating the lattice volume variation under high-voltage cycling. Our work provides a fundamental understanding of heteroatom mitigation behavior in layered cathodes at the atomic level for next-generation energy storage technologies.

18.
Sleep Med ; 112: 308-315, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37952479

RESUMEN

OBJECTIVE: The objective of this study is to analyze the association between sleep quality, sleep duration, sleep patterns, and depressive states among centenarians due to the crucial impact of depression on the well-being of elderly individuals, particularly the oldest. Recognizing easily identifiable manifestations and risk factors is essential since the onset of depressive states tends to be insidious. METHODS: The baseline data from the China Hainan Centenarians Cohort Study (CHCCS) served as the basis for this study. Questionnaire surveys were conducted to obtain research indicators, with depressive states evaluated using the GDS-15 scale and sleep quality evaluated using the Pittsburgh Sleep Quality Index (PSQI). Logistic regression was employed to describe the association between sleep status and depressive states. RESULTS: A total of 994 centenarians, with an age range of 100-116 years and a mean age of 102.77 ± 2.75 years, were included in this study. Among these participants, 815 were female, accounting for 82.0 %. After adjustment, the odds ratio (OR) for the association between poor sleep quality and depressive states was 2.07 (95 % CI: 1.54-2.77) compared to those with normal sleep quality. Additionally, there were associations between depressive states and both nighttime sleep duration and total sleep duration. After adjustment, the strongest association between depressive state and sleep patterns was found for those who had >9 h of nighttime sleep and ≥2 h of daytime sleep (OR = 1.80, 95%CI: 1.02-3.16). Moreover, compared to centenarians with 7-9 h of sleep duration and good sleep quality, the highest odds ratio (OR = 3.44, 95%CI: 2.18-5.43) for the association between depressive states and sleep duration ≤7 h and poor sleep quality was observed. CONCLUSION: The findings of this study indicate that there is an association between poor sleep quality and depressive states in centenarians. Furthermore, both sleep quality and long/short total sleep duration are associated with depressive states in this population. Therefore, special attention should be given to the psychological state of elderly individuals with short sleep duration and poor sleep quality in order to prevent depression and minimize its negative impact on their overall health.


Asunto(s)
Centenarios , Trastornos del Inicio y del Mantenimiento del Sueño , Anciano de 80 o más Años , Humanos , Femenino , Anciano , Masculino , Estudios de Cohortes , Sueño , Factores de Riesgo , China/epidemiología , Depresión/psicología
19.
Micromachines (Basel) ; 13(4)2022 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-35457833

RESUMEN

3D printing, that is, additive manufacturing, has solved many major problems in general manufacturing, such as three-dimensional tissue structure, microenvironment control difficulty, product production efficiency and repeatability, etc., improved the manufacturing speed and precision of personalized bone implants, and provided a lot of support for curing patients with bone injuries. The application of 3D printing technology in the medical field is gradually extensive, especially in orthopedics. The purpose of this review is to provide a report on the related achievements of bone implants based on 3D printing technology in recent years, including materials, molding methods, optimization of implant structure and performance, etc., in order to point out the existing shortcomings of 3D printing bone implants, promote the development of all aspects of bone implants, and make a prospect of 4D printing, hoping to provide some reference for the subsequent research of 3D printing bone implants.

20.
Zhongguo Gu Shang ; 35(2): 159-62, 2022 Feb 25.
Artículo en Zh | MEDLINE | ID: mdl-35191269

RESUMEN

OBJECTIVE: To investigate the short-term clinical effect of lumbar nerve root canal injection under X-ray angiography in the treatment of sciatica. METHODS: The clincal data of 78 patients with sciatica underwent lumbar nerve root canal injection under X-ray angiography from December 2017 to February 2020 was retrospectively analyzed. Including 31 males and 47 females, aged from 22 to 88 years old with a median of 65 years. There were 55 cases of lumbar disc herniation and 23 cases of lumbar spinal stenosis, the course of disease ranged from 1 to 8 weeks with a median of 3 weeks. There were 71 cases of single segment disc herniation or stenosis, including L3,4 of 5 cases, L4,5 of 61 cases, L5S1 of 5 cases, and 7 cases of multisegment herniation or stenosis. The pain visual analogue scale (VAS) was recorded and Macnab was used to evaluate the clinical effect. RESULTS: All patients completed standardized treatment without serious adverse reactions. VAS were (3.21±0.76) scores immediately after treatment, (2.89±0.33) scores 1 hour after treatment, (1.80±0.27) scores 6 hours after treatment, (1.10±0.20) scores 24 hours after treatment, (2.53±0.35) scores 1 week after treatment and (4.27±0.36) scores 1 month after treatment. There were significant differences in VAS between before treatment(7.83±0.56) and each time period after treatment(P<0.05). According to Macnab low back pain evaluation standard, 42 cases were effective, 34 cases were markedly effective and 2 cases were ineffective within 24 hours after treatment, with an effective rate of 97.4%;38 cases were effective, 25 cases were markedly effective, 15 cases were ineffective within one week after treatment, the effective rate was 80.0%;32 cases were effective, 22 cases were markedly effective, 24 cases were ineffective within one month after treatment, the effective rate was 69.2%. CONCLUSION: The short-term clinical effect of nerve root canal injection under X-ray radiography in the treatment of sciatica is good and it is an effective method to relieve sciatica.


Asunto(s)
Desplazamiento del Disco Intervertebral , Ciática , Adulto , Anciano , Anciano de 80 o más Años , Angiografía , Cavidad Pulpar , Femenino , Humanos , Desplazamiento del Disco Intervertebral/diagnóstico por imagen , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Ciática/diagnóstico por imagen , Ciática/tratamiento farmacológico , Resultado del Tratamiento , Rayos X , Adulto Joven
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