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1.
Small ; 20(32): e2312003, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38644338

RESUMEN

Enhancing the thermoelectric performance of n-type polycrystalline SnSe is essential, addressing challenges posed by elevated thermal conductivity and compromised power factor inherent in its intrinsic p-type characteristics. This investigation utilized solid-state reactions and spark plasma sintering techniques for the synthesis of n-type SnSe. A significant improvement in the figure of merit (ZT) is achieved through strategic reduction in Se concentration and optimization of crystal orientation. The co-doping with Br and Ge further improves the material; Br amplifies carrier concentration, enhancing electrical conductivity, while Ge introduces effective phonon scattering centers. In the Br/Ge co-doped SnSe sample, thermal conductivity dropped to 0.38 Wm⁻¹K⁻¹, yielding a remarkable power factor of 662 µW mK- 2 at 773 K, culminating in a ZT of 1.34. This signifies a noteworthy 605% improvement over the pristine sample, underscoring the pivotal role of Ge doping in enhancing n-type material thermoelectric properties. The enhancement is attributed to Br doping introducing additional electronic states near the valence band, and Ge doping modifying the band structure, fostering resonant states near the conduction band. The Br/Ge co-doping further transforms the band structure, influencing electrical conductivity, Seebeck coefficient, and thermal conductivity, advancing the understanding and application of n-type SnSe materials for superior thermoelectric performance.

2.
J Environ Manage ; 368: 122197, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39142106

RESUMEN

Agricultural production and sustainable human livelihoods in large river basins are threatened by climate change, human activities, and resource constraints. However, due to the complexity of socio-ecological interactions and agricultural sustainability, current studies are still limited by a priori knowledge and systematic analyses, as well as by the lack of quantification and identification of key factors and valuable pathway structures for agricultural production activities. Here, we combined observation-based causal inference and network analysis to quantify and assess the complex interactions in agricultural production in the Yellow River Basin (YRB) based on data from 12 factors relevant to agriculture over 40 years. We quantitatively assessed the leveraging and hindering roles of the factors in the interacting network system and provided managers with optimization priorities and possible causal pathways to achieve sustainable agriculture in the basin. For example, the fruit yield and income of rural households were identified as leveraging factors that positively affect the agricultural economy. Groundwater was seen as a hindering factor in dampening the negative impacts of the system, highlighting the importance of preventing groundwater depletion. Moreover, the findings suggest that spatially diverse causal interaction structures exist in the YRB and have shaped a variety of distinctive agricultural development modes. Our research ideas and results highlight both systemic considerations and the amplifying or dampening role of factors in interaction pathways, providing valuable quantitative insights into the management and intervention of sustainable agriculture in large river basins. Owing to replaceable and extensible network models, the methodology has the potential to be utilized in a variety of study areas and topics with complex socio-ecological interactions.


Asunto(s)
Agricultura , Ríos , Humanos , Cambio Climático , Conservación de los Recursos Naturales , Agua Subterránea
3.
J Environ Manage ; 367: 122071, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39098077

RESUMEN

As research on the full spectrum of ecosystem service (ES) generation and utilization within coupled human and natural systems (CHANS) has expanded, many studies have shown that the spatiotemporal dynamics of ESs are managed and influenced by human activities. However, there is insufficient research on how ESs are affected by bidirectional coupling between societal and ecological factors during spatial flow, particularly in terms of cross-scale impacts. These bidirectional influences between humans and nature are closely related to the utilization and transfer of ESs and affect the perception of spatiotemporal patterns of ESs and the formulation of management strategies. To fill this research gap, this study focuses on the Yellow River Basin (YRB), using network models to track the spatial dynamics of ES flows (ESFs) and the interactions between ecosystems and socio-economic systems within the basin on an annual scale from 2000 to 2020. The results highlight cross-scale impacts and feedback processes between local subbasins and the larger regional basin: As the supply-demand ratios of freshwater ESs, soil conservation ESs, and food ESs increase within individual subbasins of the YRB, more surplus ESs flow among subbasins. This not only alleviates spatial mismatches in ES supply and demand across the entire basin but also enhances the connectivity of the basin's ESF network. Subsequently, the cascading transfer and accumulation of ESs feedback into local socio-ecological interactions, with both socio-economic factors and the capacity for ES output within subbasins becoming increasingly reliant on external ES inflows. These results underscore the crucial role of ESFs within the CHANS of the YRB and imply the importance of cross-regional cooperation and cross-scale management strategies in optimizing ES supply-demand relationships. Furthermore, this study identifies the potential risks and challenges inherent in highly coupled systems. In conclusion, this work deepens the understanding of the spatial flow characteristics of ESs and their socio-ecological interactions; the analytical methods used in this study can also be applied to research on large river basins like the YRB, and even larger regional ecosystems.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Ríos , Humanos , Ecología
4.
Stroke ; 54(12): 3153-3164, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37886851

RESUMEN

BACKGROUND: Moyamoya disease (MMD) is a rare progressive vascular disease that leads to intracranial internal carotid artery stenosis and eventual occlusion. However, its pathogenesis remains unclear. The purpose of this study is to explore the role of abnormally expressed proteins in the pathogenesis of MMD. METHODS: Data-independent acquisition mass spectrometry identifies the differentially expressed proteins in MMD serum by detecting the serum from 60 patients with MMD and 20 health controls. The differentially expressed proteins were validated using enzyme linked immunosorbent assays. Immunofluorescence for superficial temporal artery and middle cerebral artery specimens was used to explore the morphological changes of vascular wall in MMD. In vitro experiments were used to explore the changes and mechanisms of differentially expressed proteins on endothelial cells. RESULTS: Proteomic analysis showed that a total of 14 726 peptides and 1555 proteins were quantified by mass spectrometry data. FLNA (filamin A) and ZYX (zyxin) proteins were significantly higher in MMD serum compared with those in health controls (Log2FC >2.9 and >2.8, respectively). Immunofluorescence revealed an intimal hyperplasia in superficial temporal artery and middle cerebral artery specimens of MMD. FLNA and ZYX proteins increased the proportion of endothelial cells in S phase and promoted their proliferation, angiogenesis, and cytoskeleton enlargement. Mechanistic studies revealed that AKT (serine/threonine kinase)/GSK-3ß (glycogen synthase kinase 3ß)/ß-catenin signaling pathway plays a major role in these FLNA- and ZYX-induced changes in endothelial cells. CONCLUSIONS: This study provides proteomic data on a large sample size of MMD. The differential expression of FLNA and ZYX in patient with MMD and following in vitro experiments suggest that these upregulated proteins are related to the pathology of cerebrovascular intimal hyperplasia in MMD and are involved in MMD pathogenesis, with diagnostic and therapeutic ramifications.


Asunto(s)
Enfermedad de Moyamoya , Humanos , Enfermedad de Moyamoya/patología , Glucógeno Sintasa Quinasa 3 beta , Proteínas del Citoesqueleto , Células Endoteliales/metabolismo , Proteómica , Hiperplasia/patología , Neovascularización Patológica
5.
Angiogenesis ; 26(2): 295-312, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36719480

RESUMEN

Cerebral cavernous malformations (CCMs) refer to a common vascular abnormality that affects up to 0.5% of the population. A somatic gain-of-function mutation in MAP3K3 (p.I441M) was recently reported in sporadic CCMs, frequently accompanied by somatic activating PIK3CA mutations in diseased endothelium. However, the molecular mechanisms of these driver genes remain elusive. In this study, we performed whole-exome sequencing and droplet digital polymerase chain reaction to analyze CCM lesions and the matched blood from sporadic patients. 44 of 94 cases harbored mutations in KRIT1/CCM2 or MAP3K3, of which 75% were accompanied by PIK3CA mutations (P = 0.006). AAV-BR1-mediated brain endothelial-specific MAP3K3I441M overexpression induced CCM-like lesions throughout the brain and spinal cord in adolescent mice. Interestingly, over half of lesions disappeared at adulthood. Single-cell RNA sequencing found significant enrichment of the apoptosis pathway in a subset of brain endothelial cells in MAP3K3I441M mice compared to controls. We then demonstrated that MAP3K3I441M overexpression activated p38 signaling that is associated with the apoptosis of endothelial cells in vitro and in vivo. In contrast, the mice simultaneously overexpressing PIK3CA and MAP3K3 mutations had an increased number of CCM-like lesions and maintained these lesions for a longer time compared to those with only MAP3K3I441M. Further in vitro and in vivo experiments showed that activating PI3K signaling increased proliferation and alleviated apoptosis of endothelial cells. By using AAV-BR1, we found that MAP3K3I441M mutation can provoke CCM-like lesions in mice and the activation of PI3K signaling significantly enhances and maintains these lesions, providing a preclinical model for the further mechanistic and therapeutic study of CCMs.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I , Hemangioma Cavernoso del Sistema Nervioso Central , MAP Quinasa Quinasa Quinasa 3 , Animales , Ratones , Células Endoteliales/metabolismo , Endotelio/metabolismo , Hemangioma Cavernoso del Sistema Nervioso Central/genética , Hemangioma Cavernoso del Sistema Nervioso Central/patología , Mutación/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , MAP Quinasa Quinasa Quinasa 3/genética , MAP Quinasa Quinasa Quinasa 3/metabolismo , Fosfatidilinositol 3-Quinasa Clase I/genética , Fosfatidilinositol 3-Quinasa Clase I/metabolismo
6.
J Environ Manage ; 326(Pt A): 116644, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36370611

RESUMEN

Humans and water are closely connected in large river basins and form social-ecological systems (SESs). However, cross-scale effect in SESs make it difficult to identify the key forces driving human-water connections at the community scale when ignoring the landscape context. Focusing on the incongruous human-water relationships in the lower reaches of the Yellow River, we built local resident perception-based networks linking the agricultural subsystem, environmental subsystem, and cultural subsystem by distributing farmer household questionnaires and extracted 13 indicators from 7 kinds of network metrics to indicate human-water connections. We applied analysis of variance (ANOVA), random forest (RF) and multilevel linear model (MLM) methods to identify the driving forces of perception-based human-water connections among 20 factors at both the community and landscape scales. The results showed that the perception-based network indicators were mainly directly influenced by community-level driving factors, especially the accessibility of information, such as the frequency of going out, the frequency of accessing the Yellow River channel, and the information source for the national policy on the Yellow River. The influences of community-level driving factors on network indicators were affected by landscape-level driving factors, e.g., the nighttime light, population density, gross domestic product and proportion of artificial land, thus indicating indirect influences from the landscape context. These analyses and findings can enrich the methods by which social, ecological and hydrological elements are structurally linked in sociohydrologic research and highlight the cross-scale effect of the landscape context on human-water systems at the community level.


Asunto(s)
Ríos , Agua , Humanos , Monitoreo del Ambiente/métodos , Ecosistema , Percepción , China
7.
Biosci Biotechnol Biochem ; 86(3): 331-339, 2022 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-34888627

RESUMEN

As one of the most common pathological changes in trauma and surgery practice, intestinal ischemia-reperfusion (I/R) injury is regarded as a major precipitating factor in the occurrence and development of fatal diseases. BRCA1-BRCA2-containing complex subunit 36 (BRCC36), a deubiquitinase, has been proved important in a variety of pathophysiological processes such as DNA repair, cell cycle regulation, tumorigenesis, and inflammatory response. However, the effect of BRCC36 on intestinal mucosal barrier injury after I/R has not been fully elucidated. Our research found that BRCC36 aggravated intestinal mucosal barrier injury caused by bone morphogenetic protein 2 after I/R by downregulating peroxisome proliferator-activated receptor-γ (PPARγ) signaling. These results suggested that BRCC36/PPARγ axis might serve as a potential therapeutic target for preventing intestinal mucosal barrier injury after I/R.


Asunto(s)
PPAR gamma
8.
Conserv Biol ; 33(5): 1076-1083, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-30693984

RESUMEN

Land degradation is a global problem that seriously threatens human society. However, in China and elsewhere, ecological restoration still largely relies on a traditional approach that focuses only on ecological factors and ignores socioeconomic factors. To improve the effectiveness of ecological restoration and maximize its economic and ecological benefits, a more efficient approach is needed that provides support for policy development and land management and thereby promotes environmental conservation. We devised a framework for assessing the value of ecosystem services that remain after subtracting costs, such as the opportunity costs, costs of forest protection, and costs for the people who are affected by the program; that is, the net value of ecosystem services (NVES). To understand the difference between the value of a resource and the net value of the ecosystem service it provides, we used data on VES, timber sales, and afforestation costs from China's massive national afforestation programs to calculate the net value of forest ecosystem services in China. Accounting for the abovementioned costs revealed an NVES of ¥6.1 × 1012 for forests in 2014, which was 35.9% less than the value calculated without accounting for costs. As a result, the NVES associated with afforestation was 55.9% less than the NVES of natural forests. In some regions, NVES was negative because of the huge costs of human-made plantations, high evapotranspiration rates (thus, high water opportunity costs), and low forest survival rates. To maximize the ecological benefits of conservation, it is necessary to account for as many costs as possible so that management decisions can be based on NVES, thereby helping managers choose projects that maximize both economic and ecological benefits.


Diferencias en el Valor Neto de los Servicios Ecológicos entre los Bosques Naturales y Artificiales de China Resumen La degradación del suelo es un problema global que amenaza seriamente a la sociedad humana. Sin embargo, en China y en otras partes, la restauración ecológica todavía depende en gran parte de una estrategia tradicional que se enfoca solamente en los factores ecológicos e ignora los socioeconómicos. Para aumentar la efectividad de la restauración ecológica y maximizar sus beneficios ecológicos y económicos se necesita de una estrategia más eficiente, la cual proporcione un respaldo para el desarrollo de políticas y el manejo del suelo y así promueva la conservación ambiental. Diseñamos un marco de trabajo para la evaluación del valor de los servicios ambientales que permanecen cuando se restan los costos, como los costos de oportunidad, los costos por la protección del bosque, y los costos para quien es afectado por el programa; es decir, el valor neto de los servicios ambientales (NVES, en inglés). Para entender la diferencia entre el valor de un recurso y el valor neto del servicio ambiental que proporciona usamos datos del valor del servicio ambiental, ventas de madera y costos por repoblación forestal tomados de los enormes programas nacionales de repoblación forestal de China para calcular el valor neto de los servicios ambientales de los bosques en ese mismo país. Cuando consideramos los costos antes mencionados, se reveló un NVES de ¥6.1 × 1012 para los bosques en 2014, el cual fue un 35.9% menos que el valor calculado sin considerar los costos. Como resultado, el NVES asociado con la repoblación forestal fue 55.9% menor que el NVES de los bosques naturales. En algunas regiones, el NVES fue negativo debido a los altos costos de las plantaciones artificiales, las tasas altas de evapo-transpiración (por lo tanto, altos costos de oportunidad hídrica) y las tasas bajas de supervivencia de los bosques. Para maximizar los beneficios ecológicos de la conservación es necesario tomar en cuenta el mayor número posible de costos para que las decisiones de manejo puedan basarse en los NVES, por lo que ayudarían a los administradores a elegir proyectos que incrementen los beneficios sociales y económicos.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , China , Ecología , Bosques , Humanos
9.
J Environ Manage ; 183(Pt 3): 843-849, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27666647

RESUMEN

Land degradation is a global environmental problem that jeopardizes human safety and socioeconomic development. To alleviate severe soil erosion and desertification due to deforestation and overgrazing, China has implemented historically unprecedented large-scale afforestation. However, few studies have accounted for the resulting imbalance between water supply (primarily precipitation) and water consumption (evapotranspiration), which will affect ecosystem health and socioeconomic development. We compared the water balance results between restoration by means of afforestation and restoration using the potential natural vegetation to guide future ecological restoration planning and environmental policy development. Based on estimates of water consumption from seven evapotranspiration models, we discuss the consequences for water security using data obtained since 1952 under China's large-scale afforestation program. The models estimated that afforestation will increase water consumption by 559-2354 m3/ha annually compared with natural vegetation. Although afforestation is a potentially important approach for environmental restoration, China's current policy has not been tailored to local precipitation conditions, and will have therefore exacerbated water shortages and decrease the ability to achieve environmental policy goals. Our analysis shows how, both in China and around the world, future ecological restoration planning must account for the water balance to ensure effective and sustainable environmental restoration policy.


Asunto(s)
Ecosistema , Restauración y Remediación Ambiental/métodos , Bosques , China , Conservación de los Recursos Naturales , Países en Desarrollo , Modelos Teóricos , Suelo , Abastecimiento de Agua
10.
Polymers (Basel) ; 16(6)2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38543398

RESUMEN

Probiotics have attracted great interest from many researchers due to their beneficial effects. Encapsulation of probiotics into biopolymer matrices has led to the development of active food packaging materials as an alternative to traditional ones for controlling food-borne microorganisms, extending food shelf life, improving food safety, and achieving health-promoting effects. The challenges of low survival rates during processing, storage, and delivery to the gut and low intestinal colonization, storage stability, and controllability have greatly limited the use of probiotics in practical food-preservation applications. The encapsulation of probiotics with a protective matrix can increase their resistance to a harsh environment and improve their survival rates, making probiotics appropriate in the food packaging field. Cellulose has attracted extensive attention in food packaging due to its excellent biocompatibility, biodegradability, environmental friendliness, renewability, and excellent mechanical strength. In this review, we provide a brief overview of the main types of cellulose used for probiotic encapsulation, as well as the current advances in different probiotic encapsulating strategies with cellulose, grafted cellulose, and cellulose-derived materials, including electrospinning, cross-linking, in-situ growth, casting strategies, and their combinations. The effect of cellulose encapsulation on the survival rate of probiotics and the patented encapsulated probiotics are also introduced. In addition, applications of cellulose-encapsulated probiotics in the food industry are also briefly discussed. Finally, the future trends toward developing encapsulated probiotics with improved health benefits and advanced features with cellulose-based materials are discussed.

11.
ACS Appl Mater Interfaces ; 16(10): 13305-13315, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38421948

RESUMEN

Photochromic materials with rapid color-switching, long color retention times, and rewritability are crucial for meeting the requirements of future rewritable ink-free media. However, these requirements are challenging to satisfy simultaneously due to the inherent constraints among these features. Herein, a novel photochromic nanofiber nonwoven fabric was designed and constructed based on a conjugated organic-inorganic hybrid structure through electrospinning and hot-pressing techniques. The as-prepared fabric can change color in merely 5 s under UV irradiation and can reach saturation within 2 min. In addition, upon the introduction of a potent metal chelator, its color retention time exceeds 14 days under ambient conditions, significantly longer than that of most rewritable materials recently reported (several hours to 5 days). Moreover, the fabric exhibits high writing resolution and can be photoprinted and heat-erased for over 100 cycles while still retaining 96% of its initial reflectivity. Hydrophobic thermoplastic polyurethane provides the fabric with excellent waterproof and antifouling properties, thus preventing the composite from swelling or collecting graffiti due to moisture or dust. This work exploits a competitive approach for designing flexible, rewritable, and superior functional wearables with practical applications.

12.
Sci Rep ; 14(1): 10278, 2024 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704490

RESUMEN

Moyamoya disease (MMD) is a cerebrovascular narrowing and occlusive condition characterized by progressive stenosis of the terminal portion of the internal carotid artery and the formation of an abnormal network of dilated, fragile perforators at the base of the brain. However, the role of PANoptosis, an apoptotic mechanism associated with vascular disease, has not been elucidated in MMD. In our study, a total of 40 patients' genetic data were included, and a total of 815 MMD-related differential genes were screened, including 215 upregulated genes and 600 downregulated genes. Among them, DNAJA3, ESR1, H19, KRT18 and STK3 were five key genes. These five key genes were associated with a variety of immune cells and immune factors. Moreover, GSEA (gene set enrichment analysis) and GSVA (gene set variation analysis) showed that the different expression levels of the five key genes affected multiple signaling pathways associated with MMD. In addition, they were associated with the expression of MMD-related genes. Then, based on the five key genes, a transcription factor regulatory network was constructed. In addition, targeted therapeutic drugs against MMD-related genes were obtained by the Cmap drug prediction method: MST-312, bisacodyl, indirubin, and tropanyl-3,5-dimethylbenzoate. These results suggest that the PANoptosis-related genes may contribute to the pathogenesis of MMD through multiple mechanisms.


Asunto(s)
Redes Reguladoras de Genes , Enfermedad de Moyamoya , Humanos , Enfermedad de Moyamoya/genética , Enfermedad de Moyamoya/inmunología , Apoptosis/genética , Perfilación de la Expresión Génica , Masculino , Transducción de Señal/genética , Femenino , Regulación de la Expresión Génica
13.
Front Genet ; 15: 1417329, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919950

RESUMEN

Introduction: Moyamoya disease (MMD) is a chronic cerebrovascular disease that can lead to ischemia and hemorrhagic stroke. The relationship between oxidative phosphorylation (OXPHOS) and MMD pathogenesis remains unknown. Methods: The gene expression data of 60 participants were acquired from three Gene Expression Omnibus (GEO) datasets, including 36 and 24 in the MMD and control groups. Differentially expressed genes (DEGs) between MMD patients MMD and control groups were identified. Machine learning was used to select the key OXPHOS-related genes associated with MMD from the intersection of DEGs and OXPHOS-related gene sets. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), gene set enrichment analysis (GSEA), Immune infiltration and microenvironments analysis were used to analyze the function of key genes. Machine learning selected four key OXPHOS-related genes associated with MMD: CSK, NARS2, PTPN6 and SMAD2 (PTPN6 was upregulated and the other three were downregulated). Results: Functional enrichment analysis showed that these genes were mainly enriched in the Notch signaling pathway, GAP junction, and RNA degradation, which are related to several biological processes, including angiogenesis, proliferation of vascular smooth muscle and endothelial cells, and cytoskeleton regulation. Immune analysis revealed immune infiltration and microenvironment in these MMD samples and their relationships with four key OXPHOS-related genes. APC co-inhibition (p = 0.032), HLA (p = 0.001), MHC I (p = 0.013), T cellco- inhibition (p = 0.032) and Type I IFN responses (p < 0.001) were significantly higher in the MMD groups than those in the control groups. The CSK positively correlated with APC co-inhibition and T cell-co-inhibition. The NARS2 negatively correlated with Type I IFN response. The SMAD2 negatively correlated with APC co-inhibition and Type I IFN response. The PTPN6 positively correlated with HLA, MHC I and Type I IFN responses. Discussion: This study provides a comprehensive understanding of the role of OXPHOS in MMD and will contribute to the development of new treatment methods and exploration of MMD pathogenesis.

14.
iScience ; 27(2): 108923, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38323000

RESUMEN

Moyamoya disease (MMD) is a rare cerebrovascular disorder marked by progressive stenosis of the internal carotid arteries. Assessing cerebral hemodynamics, specifically cerebrovascular reactivity (CVR), is vital for MMD management and prognosis. In this study, fMRI was performed in a prospective cohort of 47 patients with MMD and 32 healthy controls to investigate its utility in evaluating CVR and to explore the influence of cerebral posterior circulation compensation on CVR in MMD. The regions where the CVR values of participants with MMD were lower than those of healthy controls were primarily concentrated in the frontal, parietal, and temporal lobes (p < 0.05). In certain regions mainly supplied by posterior circulation, the CVR values of compensatory-normal subgroup tended to exceed those of compensatory-poor subgroup. fMRI can detect a significant decrease in CVR values in patients with MMD compared to healthy controls. Compensation for the posterior cerebral circulation may affect cerebrovascular reactivity.

15.
Sci Rep ; 14(1): 8607, 2024 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615120

RESUMEN

Stellera chamaejasme (S. chamaejasme) is an important medicinal plant with heat-clearing, detoxifying, swelling and anti-inflammatory effects. At the same time, it is also one of the iconic plants of natural grassland degradation in northwest China, playing a key role in the invasion process. Plant endophytes live in healthy plant tissues and can synthesize substances needed for plant growth, induce disease resistance in host plants, and enhance plant resistance to environmental stress. Therefore, studying the root endophytes of S. chamaejasme is of great significance for mining beneficial microbial resources and biological prevention and control of S. chamaejasme. This study used Illumina MiSeq high-throughput sequencing technology to analyze the composition and diversity of endophytes in the roots of S. chamaejasme in different alpine grasslands (BGC, NMC and XGYZ) in Tibet. Research results show that the main phylum of endophytic fungi in the roots of S. chamaejasme in different regions is Ascomycota, and the main phyla of endophytic bacteria are Actinobacteria, Proteobacteria and Firmicutes (Bacteroidota). Overall, the endophyte diversity of the NMC samples was significantly higher than that of the other two sample sites. Principal coordinate analysis (PCoA) and permutational multivariate analysis of variance (PERMANOVA) results showed significant differences in the composition of endophytic bacterial and fungal communities among BGC, NMC and XGYZ samples. Co-occurrence network analysis of endophytes showed that there were positive correlations between fungi and some negative correlations between bacteria, and the co-occurrence network of bacteria was more complex than that of fungi. In short, this study provides a vital reference for further exploring and utilizing the endophyte resources of S. chamaejasme and an in-depth understanding of the ecological functions of S. chamaejasme endophytes.


Asunto(s)
Actinobacteria , Thymelaeaceae , Endófitos/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Thymelaeaceae/genética , Análisis de Varianza
16.
J Neurosurg ; 140(3): 792-799, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37724811

RESUMEN

OBJECTIVE: The authors aimed to investigate the evolutionary characteristics of the Zabramski classification of cerebral cavernous malformations (CCMs) and the value of the Zabramski classification in predicting clinical outcome in patients with sporadic CCM. METHODS: This retrospective study consecutively included cases of sporadic CCM that had been untreated from January 2001 through December 2021. Baseline and follow-up patient information was recorded. The evolution of the Zabramski classification of a sporadic CCM was defined as the initial lesion type changing into another type for the first time on MRI follow-up. The primary outcome was the occurrence of a hemorrhage event, which was defined as a symptomatic event with radiological evidence of overt intracerebral hemorrhage. RESULTS: Among the 255 included cases, 55 (21.6%) were classified as type I CCM, 129 (50.6%) as type II CCM, and 71 (27.8%) as type III CCM, based on initial MRI. During a mean follow-up of 58.8 ± 33.6 months, 51 (20.0%) patients had lesion classification transformation, whereas 204 (80.0%) patients maintained their initial type. Among the 51 transformed lesions, 29 (56.9%) were type I, 11 (21.6%) were type II, and 11 (21.6%) were type III. Based on all follow-up imaging, of the initial 55 type I lesions, 26 (47.3%) remained type I and 27 (49.1%) regressed to type III because of hematoma absorption; 91.5% of type II and 84.5% of type III lesions maintained their initial type during MRI follow-up. The classification change rate of type I lesions was statistically significantly higher than those of type II and III lesions. After a total follow-up of 1157.7 patient-years, new clinical hemorrhage events occurred in 40 (15.7%) patients. The annual cumulative incidence rate for symptomatic hemorrhage in all patients was 3.4 (95% CI 2.5-4.7) per 100 person-years. Kaplan-Meier survival analysis showed that the annual cumulative incidence rate for symptomatic hemorrhage of type I CCM (15.3 per 100 patient-years) was significantly higher than those of type II (0.6 per 100 patient-years) and type III (2.3 per 100 patient-years). CONCLUSIONS: This study suggests that the Zabramski classification is helpful in estimating clinical outcome and can assist with surgical decision-making in patients with sporadic CCM.


Asunto(s)
Hemangioma Cavernoso del Sistema Nervioso Central , Humanos , Estudios Retrospectivos , Hemangioma Cavernoso del Sistema Nervioso Central/complicaciones , Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico por imagen , Hemangioma Cavernoso del Sistema Nervioso Central/epidemiología , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/etiología , Hemorragia Cerebral/epidemiología , Imagen por Resonancia Magnética/efectos adversos , Estimación de Kaplan-Meier
17.
Ambio ; 52(12): 1882-1894, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37418131

RESUMEN

Eco-civilization, as a civilizational discourse led by China, implies the next stage of civilization after industrial civilization, the essence of which is to respect, conform to, and protect nature. Although the international community is paying more attention to eco-civilization, the existing literature still lacks a systematic discussion of which theories and practices underpin the construction of eco-civilization. Due to the ambiguity of eco-civilization, some even criticize it as being a form of purely partisan politics in China. By systematically reviewing its theoretical pillars, practical actions, and major achievements, this perspective paper argues that China's eco-civilization is not a partisan politics, but rather a legitimate, imperative pathway to global sustainable development rooted in complementary theory and practice, i.e., theories guide practices, and practices enrich theories. We highlight that the theoretical basis and practical actions of eco-civilization constitute a continual improvement process that permits diverse viewpoints and understanding, and any action exploring how to achieve a harmonious coexistence between humans and nature is consistent with the values of eco-civilization.


Asunto(s)
Civilización , Desarrollo Sostenible , Humanos , China
18.
Materials (Basel) ; 16(23)2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38068172

RESUMEN

With the continuous growth of the global economy, an increasing concern has emerged among individuals with regard to personal digital health. Smart fiber-based sensors meet people's demands for wearable devices with the advantages of excellent skin-friendliness and breathability, enabling efficient and prompt monitoring of personal digital health signals in daily life. Furthermore, by integrating machine learning and big data analysis techniques, a closed-loop system can be established for personal digital health, covering data collection, data analysis, as well as medical diagnosis and treatment. Herein, we provide a review of the recent research progress on fiber-based wearable sensors for personal digital health. Firstly, a brief introduction is provided to demonstrate the importance of fiber-based wearable sensors in personal digital health. Then, the monitoring of biophysical signals through fiber-based sensors is described, and they are classified based on different sensing principles in biophysical signal monitoring (resistive, capacitive, piezoelectric, triboelectric, magnetoelastic, and thermoelectric). After that, the fiber-based biochemical signal sensors are described through the classification of monitoring targets (biofluids and respiratory gases). Finally, a summary is presented on the application prospects and the prevailing challenges of fiber-based sensors, aiming to implement their future role in constructing personal digital health networks.

19.
ACS Appl Mater Interfaces ; 15(40): 47158-47167, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37782895

RESUMEN

Herein, an n-type Ag2Se thermoelectric flexible thin film has been fabricated on a polyimide (PI) substrate via a novel thermal diffusion method, and the thermoelectric performance is well-optimized by adjusting the pressure and temperature of thermal diffusion. All of the Ag2Se films are beneficial to grow (013) preferred orientations, which is conducive to performing a high Seebeck coefficient. By increasing the thermal diffusion temperature, the electrical conductivity can be rationally regulated while maintaining the independence of the Seebeck coefficient, which is mainly attributed to the increased electric mobility. As a result, the fabricated Ag2Se thin film achieves a high power factor of 18.25 µW cm-1 K-2 at room temperature and a maximum value of 21.7 µW cm-1 K-2 at 393 K. Additionally, the thermal diffusion method has resulted in a wave-shaped buckling, which is further verified as a promising structure to realize a larger temperature difference by the simulation results of finite element analysis (FEA). Additionally, this unique surface morphology of the Ag2Se thin film also exhibits outstanding mechanical properties, for which the elasticity modulus is only 0.42 GPa. Finally, a flexible round-shaped module assembled with Sb2Te3 has demonstrated an output power of 166 nW at a temperature difference of 50 K. This work not only introduces a new method of preparing Ag2Se thin films but also offers a convincing strategy of optimizing the microstructure to enhance low-grade heat utilization efficiency.

20.
Nanomaterials (Basel) ; 13(2)2023 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-36678010

RESUMEN

For thermoelectric thin film, the substrate plays an important role during the growing process and produces effects on its thermoelectric properties. Some special kinds of substrates provide an optimal combination of influences on both the structure and thermoelectric properties. In this work, Bi-Sb-Te films are deposited on Si substrates with different initial orientations by magnetron sputtering in two ways: with and without a pre-coating process. The preferred orientations of the Bi-Sb-Te films are greatly affected by the substrates, in which the thin film tends to deposit on Si substrate with (100) initial orientation and high (015)-texture, while the (00l)-textured Bi-Sb-Te film easily deposits on Si substrate with (110) initial orientation. The experimental and theoretical calculation results indicate that Bi-Sb-Te film with (00l)-texture presents good electrical conductivity and a higher power factor than that of film with (015)-texture.

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