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1.
Sci Total Environ ; 912: 169501, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38145682

RESUMO

As climate changes increasingly influence species distributions, ecosystem functions, and biodiversity, the urgency to understand how species' ranges shift under those changes is great. Species distribution models (SDMs) are vital approaches that can predict species distributions under changing climates. However, SDMs based on the species' current occurrences may underestimate the species' climatic tolerances. Integrating species' realized niches at different periods, also known as multi-temporal calibration, can provide an estimation closer to its fundamental niche. Based on this, we further proposed an integrated framework that combines eco-evolutionary data and SDMs (phylogenetically-informed SDMs) to provide comprehensive predictions of species range shifts under climate change. To evaluate our approach's performance, we applied it to a group of related species, the Chrysanthemum zawadskii species complex (Anthemidae, Asteracee). First, we investigated the niche differentiation between species and intraspecific lineages of the complex and estimated their rates of niche evolution. Next, using both standard SDMs and our phylogenetically-informed SDMs, we generated predictions of suitability areas for all species and lineages and compared the results. Finally, we reconstructed the historical range dynamics for the species of this complex. Our results showed that the species and intraspecific lineages of the complex had varying degrees of niche differentiation and different rates of niche evolution. Lineage-level SDMs can provide more realistic predictions for species with intraspecific differentiation than species-level models can. The phylogenetically-informed SDMs provided more complete environmental envelopes and predicted broader potential distributions for all species than the standard SDMs did. Range dynamics varied among the species that have different rates of niche evolution. Our framework integrating eco-evolutionary data and SDMs contributes to a better understanding of the species' responses to climate change and can help to make more targeted conservation efforts for the target species under climate change, particularly for rare species.


Assuntos
Mudança Climática , Ecossistema , Biodiversidade
2.
Proc Natl Acad Sci U S A ; 120(33): e2301366120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549257

RESUMO

A wide range of macromolecules can undergo phase separation, forming biomolecular condensates in living cells. These membraneless organelles are typically highly dynamic, formed reversibly, and carry out essential functions in biological systems. Crucially, however, a further liquid-to-solid transition of the condensates can lead to irreversible pathological aggregation and cellular dysfunction associated with the onset and development of neurodegenerative diseases. Despite the importance of this liquid-to-solid transition of proteins, the mechanism by which it is initiated in normally functional condensates is unknown. Here we show, by measuring the changes in structure, dynamics, and mechanics in time and space, that single-component FUS condensates do not uniformly convert to a solid gel, but rather that liquid and gel phases coexist simultaneously within the same condensate, resulting in highly inhomogeneous structures. Furthermore, our results show that this transition originates at the interface between the condensate and the dilute continuous phase, and once initiated, the gelation process propagates toward the center of the condensate. To probe such spatially inhomogeneous rheology during condensate aging, we use a combination of established micropipette aspiration experiments together with two optical techniques, spatial dynamic mapping and reflective confocal dynamic speckle microscopy. These results reveal the importance of the spatiotemporal dimension of the liquid-to-solid transition and highlight the interface of biomolecular condensates as a critical element in driving pathological protein aggregation.


Assuntos
Condensados Biomoleculares , Agregação Patológica de Proteínas , Humanos , Microscopia Confocal , Reologia , Proteína FUS de Ligação a RNA
3.
ACS Omega ; 8(23): 21341-21350, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37332830

RESUMO

Irreversible colloidal asphaltene adsorption layers are formed on formation rock surfaces due to long-term contact with crude oil, and large amounts of crude oil adhere to these oil-wet layers to form residual oil films. This oil film is difficult to peel off due to the strong oil-solid interface effect, which seriously restricts further improvement in oil recovery. In this paper, the novel anionic-nonionic surfactant sodium laurate ethanolamide sulfonate (HLDEA) exhibiting strong wetting control was synthesized by introducing sulfonic acid groups into the nonionic surfactant laurate diethanolamide (LDEA) molecule through the Williamson etherification reaction. The introduction of the sulfonic acid groups greatly improved the salt tolerance and the absolute value of the zeta potential of the sand particles. The experimental results showed that HLDEA altered the wettability of the rock surface from oleophilic to strongly hydrophilic, and the underwater contact angle increased substantially from 54.7 to 155.9°. In addition, compared with LDEA, HLDEA exhibited excellent salt tolerance and enhanced oil recovery performance (the oil recovery was improved by 19.24% at 2.6 × 104 mg/L salinity). Based on nanomechanical experimental results, HLDEA was efficiently adsorbed on the core surfaces and regulated microwetting. Moreover, HLDEA effectively reduced the adhesion force between the alkane chains and the core surface, which facilitated residual oil stripping and oil displacement. This new anionic-nonionic surfactant affording great oil-solid interface wetting control has practical significance for the efficient development of residual oil.

4.
Gels ; 9(5)2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37232994

RESUMO

The mechanical strength of dispersed particle gels (DPGs), which can be directly characterized by Young's modulus, is an important parameter affecting reservoir regulation performance. However, the effect of reservoir conditions on the mechanical strength of DPGs, as well as the desired range of mechanical strength for optimum reservoir regulation performance, have not been systematically studied. In this paper, DPG particles with different Young's moduli were prepared and their corresponding migration performances, profile control capacities and enhanced oil recovery abilities were studied by simulated core experiments. The results showed that with increase in Young's modulus, the DPG particles exhibited improved performance in profile control as well as enhanced oil recovery. However, only the DPG particles with a modulus range of 0.19-0.762 kPa could achieve both adequate blockage in large pore throats and migration to deep reservoirs through deformation. Considering the material costs, applying DPG particles with moduli within the range of 0.19-0.297 kPa (polymer concentration: 0.25-0.4%; cross-linker concentration: 0.7-0.9%) would ensure optimum reservoir control performance. Direct evidence for the temperature and salt resistance of DPG particles was also obtained. When aged in reservoir conditions below 100 °C and at a salinity of 10 × 104 mg·L-1, the Young's modulus values of the DPG particle systems increased moderately with temperature or salinity, indicating a favorable impact of reservoir conditions on the reservoir regulation abilities of DPG particles. The studies in this paper indicated that the practical reservoir regulation performances of DPGs can be improved by adjusting the mechanical strength, providing basic theoretical guidance for the application of DPGs in efficient oilfield development.

5.
Chem Biodivers ; 20(2): e202200308, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36621947

RESUMO

The therapeutic effect of apigenin (APG) on hyperlipidemia was investigated using network pharmacology combined with molecular docking strategy, and the potential targets of APG in the treatment of hyperlipidemia were explored. Genetic Ontology Biological Process (GOBP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway enrichment analysis of common targets were performed. Then, molecular docking was used to predict the binding mode of APG to the target. Finally, Sprague Dawley rats were used to establish a hyperlipidemia model. The expression levels of insulin (INS) and vascular endothelial growth factor A (VEGFA) mRNA in each group were detected by quantitative reverse transcription-polymerase chain reaction. Network pharmacological studies revealed that the role of APG in the treatment of hyperlipidemia was through the regulation of INS, VEGFA, tumor necrosis factor, epidermal growth factor receptor, matrix metalloprotein 9, and other targets, as well as through the regulation of the hypoxia-inducible factor 1 (HIF-1) signaling pathway, fluid shear stress, and atherosclerosis signaling pathways, vascular permeability; APG also participated in the regulation of glucose metabolism and lipid metabolism, and acted on vascular endothelial cells, and regulated vascular tone. Molecular docking showed that APG binds to the target with good efficiency. Experiments showed that after APG treatment, the expression levels of INS and VEGFA mRNA in the model group were significantly decreased (p<0.01). In conclusion, APG has multiple targets and affects pathways involved in the treatment of hyperlipidemia by regulating the HIF-1 signaling pathway, fluid shear stress, and the atherosclerosis pathway.


Assuntos
Aterosclerose , Medicamentos de Ervas Chinesas , Hiperlipidemias , Ratos , Animais , Ratos Sprague-Dawley , Apigenina , Fator A de Crescimento do Endotélio Vascular , Células Endoteliais , Simulação de Acoplamento Molecular , Farmacologia em Rede , Insulina
6.
Cladistics ; 38(6): 663-683, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35766338

RESUMO

A species complex is an assemblage of closely related species with blurred boundaries, and from which species could arise from different speciation processes and/or a speciation continuum. Such a complex can provide an opportunity to investigate evolutionary mechanisms acting on speciation. The Chrysanthemum zawadskii species complex in China, a monophyletic group of Chrysanthemum, consists of seven species with considerable morphological variation, diverse habitats and different distribution patterns. Here, we used Hyb-Seq data to construct a well-resolved phylogeny of the C. zawadskii complex. Then, we performed comparative analyses of variation patterns in morphology, ecology and distribution to investigate the roles of geography and ecology in this complex's diversification. Lastly, we implemented divergence time estimation, species distribution modelling and ancestral area reconstruction to trace the evolutionary history of this complex. We concluded that the C. zawadskii complex originated in the Qinling-Daba mountains during the early Pliocene and then spread west and northward along the mountain ranges to northern China. During this process, geographical and ecological factors imposing different influences resulted in the current diversification and distribution patterns of this species complex, which is composed of both well-diverged species and diverging lineages on the path of speciation.


Assuntos
Chrysanthemum , Filogenia , Chrysanthemum/genética , Geografia , Ecossistema , China
7.
Phys Rev E ; 105(4-1): 044608, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35590678

RESUMO

Despite significant advances in particle imaging technologies over the past two decades, few advances have been made in particle tracking, i.e., linking individual particle positions across time series data. The state-of-the-art tracking algorithm is highly effective for systems in which the particles behave mostly independently. However, these algorithms become inaccurate when particle motion is highly correlated, such as in dense or strongly interacting systems. Accurate particle tracking is essential in the study of the physics of dense colloids, such as the study of dislocation formation, nucleation, and shear transformations. Here, we present a method for particle tracking that incorporates information about the correlated motion of the particles. We demonstrate significant improvement over the state-of-the-art tracking algorithm in simulated data on highly correlated systems.

8.
Phys Rev Lett ; 127(10): 108101, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34533352

RESUMO

We investigate the rheological properties of interpenetrating networks reconstituted from the main cytoskeletal components: filamentous actin, microtubules, and vimentin intermediate filaments. The elastic modulus is determined largely by actin, with little contribution from either microtubules or vimentin. However, vimentin dramatically impacts the relaxation, with even small amounts significantly increasing the relaxation time of the interpenetrating network. This highly unusual decoupling between dissipation and elasticity may reflect weak attractive interactions between vimentin and actin networks.


Assuntos
Filamentos Intermediários/química , Modelos Químicos , Vimentina/química , Actinas/química , Actinas/metabolismo , Citoesqueleto/química , Citoesqueleto/metabolismo , Células Eucarióticas , Filamentos Intermediários/metabolismo , Microtúbulos/química , Microtúbulos/metabolismo , Reologia/métodos , Vimentina/metabolismo
9.
Nano Lett ; 21(17): 7371-7378, 2021 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-34423634

RESUMO

Directed differentiation enables the production of a specific cell type by manipulating signals in development. However, there is a lack of effective means to accelerate the regeneration of neurons of particular subtypes for pathogenesis and clinical therapy. In this study, we find that hydroxyapatite (HAp) nanorods promote neural differentiation of neural stem cells due to their chemical compositions. Lysosome-mediated degradation of HAp nanorods elevates intracellular calcium concentrations and accelerates GABAergic neurogenesis. As a mechanism, the enhanced activity of a Ca2+ peak initiated by HAp nanorods leads to the activation of c-Jun and thus suppresses the expression of GABAergic/glutamatergic selection gene TLX3. We demonstrate the capability of HAp nanorods in promoting the differentiation into GABAergic neurons at both molecular and cellular function levels. Given that GABAergic neurons are responsible for various physiological and pathological processes, our findings open up enormous opportunities in efficient and precise stem cell therapy of neurodegenerative diseases.


Assuntos
Nanotubos , Células-Tronco Neurais , Materiais Biocompatíveis , Diferenciação Celular , Sinais (Psicologia) , Durapatita , Neurônios GABAérgicos
10.
Inorg Chem ; 59(13): 9252-9260, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32568529

RESUMO

Sodium super ionic conductor (NASICON) Na3V2(PO4)3 (NVP) is a type of promising cathode material for sodium-ion batteries (SIBs) with superior structural integrity, high energy density, and fast diffusion of sodium ions. However, NVP suffers from intrinsically low electrical conductivity, which results in poor rate performance. Herein, we report on the outstanding cathode performance of Na3V2(PO4)3 (NVP@C-ZIF67) wrapped by the ZIF-67-derived carbon, which was prepared by sol-gel method and solid-phase method. Electrochemical measurements show an initial discharge-specific capacity of 135 mA h g-1 at 1 C, and the discharge capacity maintains 82 mA h g-1 after 1000 cycles at 10 C. The results indicate the improvement in electrical conductivity and electrochemical performance due to the Co doping from ZIF-67. Moreover, we calculate the diffusion coefficient of sodium ions by the cyclic voltammetry (CV, DNa+ = 1.521 × 10-11 and 2.3484 × 10-11 cm2 s-1 for charging and discharging, respectively) and the galvanostatic intermittent titration technique (GITT, DNa+ ranges from 10-11-10-15 cm2 s-1). The exceptional performance is ascribed to the excellent structural stability and outstanding electrical conductivity of NVP modified by porous carbon skeleton and ZIF-67-derived carbon.

11.
ACS Omega ; 4(15): 16603-16611, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31616842

RESUMO

Electrically driven steam generation is a critical process for many heating-related applications such as sterilization and food processing. Current systems, which rely on heating up the bulk water to generate steam, face the dilemma in achieving a large evaporation flux and fast thermal response. Herein, we report a self-floating electrically driven interfacial evaporator for fast high-efficiency steam generation independent of the amount of loaded bulk water in the system. Through localized heating of the wicked water at the air-water interface, the evaporator has achieved an electrical-to-steam energy conversion efficiency of ∼90% at a heating power density of 10 kW/m2 and a fast thermal response of 20 s. The interfacial evaporation design not only achieves a high evaporation efficiency within a broad range of heating power densities by using different wicking materials, but also enables attaining a high evaporation temperature under low heating power densities by tuning the ratio of the vapor outlet area and the evaporation surface area. By integrating an interfacial evaporator within a sanitizer, the resultant system has demonstrated a faster steam temperature rise and superior steam sterilization performance than the commercial bulk heating-based approach.

12.
Nat Commun ; 10(1): 3112, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308363

RESUMO

Ultrathin transition metal carbides with high capacity, high surface area, and high conductivity are a promising family of materials for applications from energy storage to catalysis. However, large-scale, cost-effective, and precursor-free methods to prepare ultrathin carbides are lacking. Here, we demonstrate a direct pattern method to manufacture ultrathin carbides (MoCx, WCx, and CoCx) on versatile substrates using a CO2 laser. The laser-sculptured polycrystalline carbides (macroporous, ~10-20 nm wall thickness, ~10 nm crystallinity) show high energy storage capability, hierarchical porous structure, and higher thermal resilience than MXenes and other laser-ablated carbon materials. A flexible supercapacitor made of MoCx demonstrates a wide temperature range (-50 to 300 °C). Furthermore, the sculptured microstructures endow the carbide network with enhanced visible light absorption, providing high solar energy harvesting efficiency (~72 %) for steam generation. The laser-based, scalable, resilient, and low-cost manufacturing process presents an approach for construction of carbides and their subsequent applications.

13.
Nat Neurosci ; 19(5): 668-677, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26998601

RESUMO

Neuronal inclusions of poly(GA), a protein unconventionally translated from G4C2 repeat expansions in C9ORF72, are abundant in patients with frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) caused by this mutation. To investigate poly(GA) toxicity, we generated mice that exhibit poly(GA) pathology, neurodegeneration and behavioral abnormalities reminiscent of FTD and ALS. These phenotypes occurred in the absence of TDP-43 pathology and required poly(GA) aggregation. HR23 proteins involved in proteasomal degradation and proteins involved in nucleocytoplasmic transport were sequestered by poly(GA) in these mice. HR23A and HR23B similarly colocalized to poly(GA) inclusions in C9ORF72 expansion carriers. Sequestration was accompanied by an accumulation of ubiquitinated proteins and decreased xeroderma pigmentosum C (XPC) levels in mice, indicative of HR23A and HR23B dysfunction. Restoring HR23B levels attenuated poly(GA) aggregation and rescued poly(GA)-induced toxicity in neuronal cultures. These data demonstrate that sequestration and impairment of nuclear HR23 and nucleocytoplasmic transport proteins is an outcome of, and a contributor to, poly(GA) pathology.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neurônios/patologia , Proteínas/toxicidade , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Atrofia/patologia , Comportamento Animal , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/ultraestrutura , Proteína C9orf72 , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Expressão Gênica/genética , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/ultraestrutura , Camundongos , Mutação , Degeneração Neural/patologia , Neurônios/metabolismo , Cultura Primária de Células , Proteínas/genética , Proteínas/metabolismo , Proteínas Ubiquitinadas/metabolismo
14.
Epilepsy Behav ; 50: 10-3, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26093217

RESUMO

Epilepsy is a multifaceted chronic neurological disorder with diverse effects on a patient's psychosocial well-being. The impact on quality of life has been well documented, and many studies have addressed the detrimental influences epilepsy has on an individual. However, the emotional impact and the influence of the condition on family members have not been well studied. Furthermore, the majority of the studies on this topic have been confined to childhood epilepsy, and there is only scarce literature that discusses the effects on family members caring for adult patients. The purpose of this literature review was to examine the influence of adult epilepsy on the psychological and social well-being of individual family members. We explored the psychological and physical well-being, satisfaction with social circumstances, and perceived level of support in families of adult patients with intractable epilepsy. The paper also suggests best practices on how to improve the family's quality of life, as well as future directions for research. Superior medical care and a positive family support system are important conditions that can help adult individuals with epilepsy best deal with their condition.


Assuntos
Epilepsia/psicologia , Saúde da Família , Família/psicologia , Estresse Psicológico/etiologia , Adaptação Psicológica , Adulto , Doença Crônica , Humanos , Transtornos Mentais/psicologia , Qualidade de Vida
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