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1.
Ergonomics ; : 1-20, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38592045

RESUMEN

Studies have demonstrated two-stage takeover systems' feasibility and advantages. However, existing cognitive models mainly focus on simulating drivers' performance in single-stage takeover systems, with limited insights into cognitive modelling of effects of monitoring requests (MRs) within two-stage takeover systems. This study constructed a cognitive computational model for two-stage takeover systems based on queueing network-adaptive control of thought rational (QN-ACTR) architecture. Our model aims to capture variations in drivers' attention allocation and takeover performance resulting from different MR experiences. Five components, representing distinct cognitive processes, were designed to closely align with drivers' behavioural patterns. This model was validated through an experiment using metrics such as percentage time in road-centre and takeover time. Results revealed significant concordance between the model predictions and experimental data, with R-squared ≥ 0.76, RMSE ≤ 0.41, and MAPE ≤ 15%. The findings of this work extended beyond the two-stage takeover system investigation to include human factor modelling.


To provide insights into modelling the effects of monitoring requests in two-stage takeover systems, a cognitive computational model was developed to simulate driver behaviour. An experiment was conducted to validate the model's predictive performance. The quantisation relation between warning signals and driver performance can be calculated through the proposed model.

2.
Bioorg Chem ; 130: 106257, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36375349

RESUMEN

Ten new indole alkaloids (1-10) as well as eleven known analogs (11-21) were isolated from the stems and hooks of Uncaria rhynchophylla. Their structure elucidation was based on extensive NMR studies, MS and ECD data, with the essential aid of DFT prediction of ECD spectra. Compound 1 was determined as a 17,19-seco-cadambine-type alkaloid, and compound 3 was confirmed to be a 3,4-seco-tricyclic monoterpene indole alkaloid, which are the first seco-alkaloids possessing such cleavage positions from U. rhynchophylla. All the isolated compounds were evaluated for their bioactivities on dopamine D2 and Mu opioid receptors for discovering natural therapeutic drugs targeting central nervous system (CNS) diseases. Compounds 1, 2, 4, 5, 20 and 21 showed antagonistic bioactivities on the D2 receptor (IC50 0.678-15.200 µM), and compounds 1, 3, 6, 9, 10, 13, 18, 19 and 21 exhibited antagonistic effects on the Mu receptor (IC50 2.243-32.200 µM). Among them, compounds 1 and 21 displayed dual-target activities. Compound 1 showed conspicuous antagonistic activity on D2 and Mu receptors with the IC50 values of 0.678 ± 0.182 µM and 13.520 ± 2.480 µM, respectively. Compound 21 displayed moderate antagonistic activity on the two receptors with the IC50 values at 15.200 ± 1.764 µM and 32.200 ± 5.695 µM, respectively.


Asunto(s)
Antagonistas de los Receptores de Dopamina D2 , Alcaloides Indólicos , Uncaria , Alcaloides/química , Alcaloides/farmacología , Dopamina/metabolismo , Alcaloides Indólicos/farmacología , Alcaloides Indólicos/química , Receptores Opioides mu/antagonistas & inhibidores , Uncaria/química , Antagonistas de los Receptores de Dopamina D2/química , Antagonistas de los Receptores de Dopamina D2/farmacología , Antagonistas de Narcóticos/química , Antagonistas de Narcóticos/farmacología
3.
Acta Biochim Biophys Sin (Shanghai) ; 55(12): 1864-1873, 2023 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-37559455

RESUMEN

DNA double-strand break (DSB) repair by homologous recombination (HR) is crucial for the maintenance of genome stability and integrity. In this study, we aim to identify novel RNA binding proteins (RBPs) involved in HR repair because little is known about RBP function in HR. For this purpose, we carry out pulldown assays using a synthetic ssDNA/dsDNA structure coated with replication protein A (RPA) to mimic resected DNA, a crucial intermediate in HR-mediated DSB repair. Using this approach, we identify RNA-binding motif protein 14 (RBM14) as a potential binding partner. We further show that RBM14 interacts with an essential HR repair factor, CtIP. RBM14 is crucial for CtIP recruitment to DSB sites and for subsequent RPA coating and RAD51 replacement, facilitating efficient HR repair. Moreover, inhibition of RBM14 expression sensitizes cancer cells to X-ray irradiation. Together, our results demonstrate that RBM14 promotes DNA end resection to ensure HR repair and may serve as a potential target for cancer therapy.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN por Recombinación , Reparación del ADN , Recombinación Homóloga , Proteína de Replicación A/genética , ADN/genética , Reparación del ADN por Unión de Extremidades
4.
J Am Chem Soc ; 144(33): 15143-15154, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35947444

RESUMEN

The electrochemical reduction reaction of carbon dioxide (CO2RR) to the desired feedstocks with a high faradaic efficiency (FE) and high stability at a high current density is of great importance but challenging owing to its poor electrochemical stability and competition with the hydrogen evolution reaction (HER). Guided by theoretical calculations, herein, a series of novel metalloporphyrin-linked mercurated graphynes (Hg-MTPP) were designed as electrocatalysts for CO2RR, since the mercurated graphyne blocks induce a high HER overpotential. Notably, Hg-CoTPP was synthesized and produced a maximum CO FE of 95.6% at -0.76 V (vs reversible hydrogen electrode (RHE)) in an H-type cell, and a CO FE of 91.2% even at -1.26 V (vs RHE), due to a great suppression of HER. The Hg-CoTPP combined with N-doped graphene (Hg-CoTPP/NG) was able to achieve a high CO FE of nearly 100% at a current density of 1.2 A cm-2 and particularly a ground-breaking stability of over 360 h at around 420 mA cm-2 in a flow-type cell. Further experimental and computational results revealed that the mercurated graphyne of Hg-CoTPP brings a high HER overpotential and tunes the d-band electronic states of the metal center that make the d-band center closer to the Fermi level, thus enhancing the bonding of *COOH intermediates on Hg-CoTPP. The introduction of NG could shorten the Co-N coordination bonds, which enhances electron transfer to the metal center to lower the energy barrier for *COOH. Our results illustrated that Hg-MTPP could serve as a new class of two-dimensional (2D) materials and provide a design concept for developing efficient electrocatalysts for CO2RR in commercial applications.

5.
Molecules ; 26(9)2021 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-33924768

RESUMEN

Although the organic and the conventional inorganic thermoelectric (TE) materials have been extensively developed in recent years, the number of cases involving conducting metallopolymers is still quite limited. In view of the versatile coordination capability of the terpyridine fraction and the electron-rich nature of the 3,4-ethylenedioxythiophene moiety, a bis-terpyridine-featured ligand was designed, and a series of metallopolymers were then synthesized. Upon the addition of single-walled carbon nanotube (SWCNT), the TE properties of the resulting metallopolymer-SWCNT composite films were investigated. It was found that metal centres played an important role in affecting the morphology of the thin films, which was a key factor that determined the TE performances of the composites. Additionally, the energy levels of the metallopolymers were feasibly tuned by selecting different metal centres. With the combined effects of a uniform and condensed surface and an optimized band structure, the highest power factor was achieved by the Cu(II)-containing metallopolymer-SWCNT composite at the doping ratio of 75%, which reached 38.3 µW·m-1·K-2.

6.
Angew Chem Int Ed Engl ; 60(20): 11326-11334, 2021 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-33626224

RESUMEN

Two-dimensional (2D) nanomaterials are attracting much attention due to their excellent electronic and optical properties. Here, we report the first experimental preparation of two free-standing mercurated graphyne nanosheets via the interface-assisted bottom-up method, which integrates both the advantages of metal center and graphyne. The continuous large-area nanosheets derived from the chemical growth show the layered molecular structural arrangement, controllable thickness and enhanced π-conjugation, which result in their stable and outstanding broadband nonlinear saturable absorption (SA) properties (at both 532 and 1064 nm). The passively Q-switched (PQS) performances of these two nanosheets as the saturable absorbers are comparable to or higher than those of the state-of-the-art 2D nanomaterials (such as graphene, black phosphorus, MoS2 , γ-graphyne, etc.). Our results illustrate that the two metallated graphynes could act not only as a new class of 2D carbon-rich materials, but also as inexpensive and easily available optoelectronic materials for device fabrication.

7.
Chem Soc Rev ; 48(23): 5547-5563, 2019 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-31720563

RESUMEN

Square planar platinum(ii) complexes have been known for 150 years and pincer complexes, supported by a tridentate chelating ligand such as terpyridyl, have been known for more than 70 years. The development of cyclometallated platinum(ii) pincer complexes, in which the tridentate ligand forms one or more platinum-carbon bonds, has been much more recent. Particularly, in terms of their solution and solid-state luminescence these cyclometallated complexes show substantial advantages over their terpyridyl analogues. This tutorial review introduces the reader to the area of platinum(ii) cyclometallated pincer chemistry and shows the advantage of having an alkynyl group in the fourth coordination site on the metal. The basic design principles for the preparation of highly luminescent platinum(ii) cyclometallated pincer complexes are outlined and the strategy to improve the luminescence further by chemical manipulation of the pincer ligand and of the auxiliary ligand in the fourth coordination site are illustrated with recent examples from the literature. Recent applications of these cyclometallated pincer complexes in the area of opto-electronics is described, with emphasis on their use in OLEDs, OFETs and as NLO materials as well as demonstrating their potential use as triplet photosensitizers and as metal ion sensors. The aim of this review is to show the recent advances in this rapidly developing research field and to highlight the future promise of these materials.

8.
Chem Soc Rev ; 47(13): 4934-4953, 2018 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-29774340

RESUMEN

In recent years, metallopolymers have attracted much attention as precursors to generate magnetic metal/metal alloy nanoparticles (NPs) through pyrolysis or photolysis because they offer the advantages of ease of solution processability, atomic level mixing and stoichiometric control over composition. The as-generated NPs usually possess narrow size distributions with precise control of composition and density per unit area. Moreover, patterned NPs can be achieved on various substrates in this way owing to the good film-forming property of metallopolymers and such work is important for many applications based on metal nanostructures. By combining the merits of both the solution processability of metallopolymers and nanoimprint lithography (NIL), a new platform can be created for fabricating bit-patterned media (BPM) and the next-generation of nanoscale ultra-high-density magnetic data storage devices. Furthermore, most of these metallopolymers can be used directly as a negative-tone resist to generate magnetic metallic nanostructures by electron-beam lithography and UV photolithography. Self-assembly and subsequent pyrolysis of metalloblock copolymers can also afford well-patterned magnetic metal or metal alloy NPs in situ with periodicity down to dozens of nanometers. In this review, we highlight the use of metallopolymer precursors for the synthesis of magnetic metal/metal alloy NPs and their nanostructures and the related applications.

9.
Immunopharmacol Immunotoxicol ; 39(3): 117-123, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28290727

RESUMEN

Benzo[a]pyrene (B[a]P) is a polycyclic aromatic hydrocarbon contaminant that is widely present in environmental sources, including food. This study aims to clarify the effects of B[a]P toxicity on activated mouse T cells in vitro. Our results show that B[a]P markedly inhibited Concanavalin A (ConA)-induced T lymphocyte proliferation and suppressed the production of the cytokines Interferon (IFN)-γ, Interleukin (IL)-2 and IL-4. Western blot and protein-DNA interaction assays were used to study how B[a]P affects signal transduction. The results revealed that B[a]P suppressed the ConA-induced activation of the Ca2+/CaM/NFκB and Ca2+/CaM/CaN/NFAT signal transduction pathways. These observations indicate that B[a]P has toxic effects on activated mouse T cells in vitro.


Asunto(s)
Benzo(a)pireno/toxicidad , Señalización del Calcio/efectos de los fármacos , Activación de Linfocitos/efectos de los fármacos , Linfocitos T/metabolismo , Animales , Concanavalina A/farmacología , Citocinas/metabolismo , Ratones , Ratones Endogámicos BALB C , Linfocitos T/patología
10.
Angew Chem Int Ed Engl ; 56(45): 14090-14095, 2017 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-28895265

RESUMEN

Zeolites with molecular dimension pores are widely used in petrochemical and fine-chemical industries. While traditional solvothermal syntheses suffer from environmental, safety, and efficiency issues, the newly developed solvent-free synthesis is limited by zeolite crystal aggregation. Herein, we report well-dispersed and faceted silicalite ZSM-5 zeolite crystals obtained using a solvent-free synthesis facilitated by graphene oxide (GO). The selective interactions between the GO sheets and different facets, which are confirmed by molecular dynamics simulations, result in oriented growth of the ZSM-5 crystals along the c-axis. More importantly, the incorporation of GO sheets into the ZSM-5 crystals leads to the formation of mesopores. Consequently, the faceted ZSM-5 crystals exhibit hierarchical pore structures. This synthetic method is superior to conventional approaches because of the features of the ZSM-5 zeolite.

11.
RSC Adv ; 14(29): 21118-21138, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38966811

RESUMEN

The fast rise of organic and metallic pollution has brought significant risks to human health and the ecological environment. Consequently, the remediation of wastewater is in extremely urgent demand and has received increasing attention. Nanoscale zero valent iron (nZVI) possesses a high specific surface area and distinctive reactive interfaces, which offer plentiful active sites for the reduction, oxidation, and adsorption of contaminants. Given these abundant functionalities of nZVI, it has undergone significant and extensive studies on environmental remediation, linking to various mechanisms, such as reduction, oxidation, surface complexation, and coprecipitation, which have shown great promise for application in wastewater treatment. Among these functionalities of nZVI, reductivity is particularly important and widely adopted in dehalogenation, and reduction of nitrate, nitro compounds, and metal ions. The following review comprises a short survey of the most recent reports on the applications of nZVI based on its reductivity. It contains five sections, an introduction to the theme, chemical reduction applications, electrolysis-assisted reduction applications, bacterium-assisted reduction applications, and conclusions about the reported research with perspectives for future developments. Review and elaboration of the recent reductivity-dependent applications of nZVI may not only facilitate the development of more effective and sustainable nZVI materials and the protocols for comprehensive utilization of nZVI, but may also promote the exploration of innovative remediation approaches based on its reductivity.

12.
Sci Total Environ ; 914: 169762, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38176560

RESUMEN

Accurate estimation of biogenic volatile organic compounds (BVOCs) emissions from urban plants is important as BVOCs affect the formation of secondary pollutants and human health. However, uncertainties exist for the estimation of BVOCs emissions from urban greenspace due to the lack of tree species classification with high spatial resolution. Here, we generated a tree species classification dataset with 10 m resolution to estimate tree species-level BVOCs emissions and quantify their impact on air quality in Shenzhen in southern China. The results showed that for the entire city, the BVOCs emissions based on traditional plant functional types (PFTs) dataset were substantially underestimated compared with the tree species classification data (6.37 kt versus 8.23 kt, with 22.60 % difference). The underestimation is particularly prominent in urban built-up areas, where our estimation was 1.65 kt, nearly twice of that based on PFTs data (0.86 kt). BVOCs estimation in built-up areas contributed approximately 20.07 % to the total. These BVOCs contributed substantially to the increase of ambient O3, but had limited impacts to ambient fine particulate matter (PM2.5). Our results underscore the importance of high spatial resolution tree species-level classification in more accurate estimation of BVOCs, especially in highly developed urban areas. The enhanced understanding of the patterns of BVOCs emissions by urban trees and the impact on secondary pollutants can better support fine-scale tree planning and management for livable environments in urban areas.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Ozono , Compuestos Orgánicos Volátiles , Humanos , Árboles , Contaminantes Atmosféricos/análisis , Compuestos Orgánicos Volátiles/análisis , Parques Recreativos , Material Particulado/análisis , Plantas , Ozono/análisis
13.
J Pain Res ; 17: 643-666, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38371481

RESUMEN

Background: Pregnancy-related Pelvic Girdle Pain (PPGP) is a prevalent condition characterized by various physiological and pathological processes in the female body. The objective of this study is to offer a comprehensive understanding of the current research landscape, key areas of interest, and potential future directions in the field of PPGP. Methods: Using Web of Science, we explored PPGP literature from 2002 to 2022. VOSviewer and CiteSpace facilitated a quantitative analysis, revealing co-authorship patterns, co-occurring themes, citations, and co-citations. Results: We identified, peaking at 99 publications in 2021. The United States led with 138 publications and the highest citation count (3160). The Karolinska Institute boasted the highest tally of publications (n = 21). Regarding the volume of publications, the esteemed journal of BMC Pregnancy and Childbirth attained the foremost position. Notably, Gutke, Annelie emerged as the most prolific and highly cited author. The analysis of keyword co-occurrence and co-citation clustering unveiled an intricate tapestry of PPGP studies, spanning various domains including risk factors, mechanistic intricacies, diagnostic benchmark, treatment modalities, and far-reaching ramifications on one's quality of life. Conclusion: Research endeavors exploring PPGP have unveiled an enduring trajectory of growth in contemporary times. The existing body of research primarily focuses on delving into the intricate interplay of epidemiological factors and the profound implications of interventions encompassing physical therapy, exercise protocols, and diverse modes of pain management within the domain of PPGP. Multidisciplinary integration encapsulates a prevailing trajectory of progress within this domain, while the focal point of future inquiries into PPGP may revolve around subjects pertaining to standardized outcome reporting.

14.
J Surg Res ; 185(2): 912-22, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23927879

RESUMEN

BACKGROUND: In addition to achieving a balance between the positive (controlling rejection) and the negative (infection and malignancy) aspects of drug-induced immunodeficiency, new immunosuppressive combinations must address the issue of nonimmune drug toxicity that may be dose limiting. Cordycepin is a type of adenosine analog extracted from Cordyceps militaris. In the present study, we investigated its immunosuppressive effect on T cell both in vitro and in vivo. METHODS: We evaluated the effects of cordycepin on concanavalin A-induced production of immune mediators in mouse splenocyte by enzyme-linked immunosorbent assay and flow cytometry. Furthermore, using Western blotting, we studied signal transduction mechanisms to determine how cordycepin inhibited T-cell activation in purified mouse T lymphocytes. To confirm the immunosuppressive activity of cordycepin in vivo, we induced the T cell-mediated delayed-type hypersensitivity reaction in a 2,4-dinitro-1-fluorobenzene-induced mouse model. RESULTS: The in vitro results showed that cordycepin markedly suppressed concanavalin A-induced splenocyte proliferation, Th1 and Th2 cytokine production, and the ratio of CD4(+)-to-CD8(+) T cells. The administration of cordycepin in vivo markedly suppressed the T cell-mediated delayed-type hypersensitivity reaction. The data revealed that cordycepin effectively shocked the nuclear factor kappa B and nuclear factor of activated T cells 2 signal transduction pathways but had no effect on the mitogen activated protein kinase signal transduction pathway. CONCLUSIONS: These observations indicated that cordycepin has a potential role in downregulating the immune system and could be developed as a useful immunosuppressive agent for treating undesired immune responses.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD8-positivos/efectos de los fármacos , Cordyceps/química , Desoxiadenosinas/farmacología , Inmunosupresores/farmacología , Animales , Antineoplásicos/farmacología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Concanavalina A/farmacología , Medicamentos Herbarios Chinos/farmacología , Citometría de Flujo , Hipersensibilidad Tardía/tratamiento farmacológico , Hipersensibilidad Tardía/inmunología , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos BALB C , Mitógenos/farmacología , FN-kappa B/inmunología , FN-kappa B/metabolismo , Bazo/citología
15.
Environ Pollut ; 318: 120886, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36549454

RESUMEN

Urban plants are beneficial to residents' physical and mental health, but can also have adverse impacts. One of the remarked examples is the potential contribution of BVOCs released by urban plants to the generation of ground-level ozone and SOA. The choice of urban plant species, therefore, is critical for air quality improvement in cities. Understanding the rates of BVOCs emitted from different urban plants and how they change in response to environmental stressors is a prerequisite to making the right decision on plant species selection. Here, we performed a meta-analysis on the selected 159 studies that include 357 species to address this need. We found: (1) 89% of deciduous trees emit the three major types of BVOCs, isoprene, monoterpene, and sesquiterpene, but only do 53% evergreen ones. (2) The main types of BVOCs emission by broad-leaved and coniferous plants differ. Seventy-eight percent of broad-leaved, but only 48% of coniferous trees emit isoprene, whereas 74% of broad-leaved, but 93% of coniferous plants emit monoterpene. (3) The emission rates of isoprene and monoterpene differ significantly among species. (4) The analysis on the 77 species collected in previous studies indicated that the effect of environmental stressors varies by different compounds, and the combined effect is not precisely the same as that of a single factor. Based on the meta-analysis, we further identified a few key knowledge gaps and research priorities. First, more studies on the BVOCs emission and carbon allocation at the tree species level are needed. Second, the combined effects of multiple environmental stresses, especially long-term ones, on BVOC emissions and the mechanisms warrant further research. Third, it is vital to evaluate BVOC-climate interactions on global change. Furthermore, there is little empirical work on the synergies and tradeoffs between BVOC emissions and ecosystem services provision of urban plants, which warrants future investigation.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Ecosistema , Contaminantes Atmosféricos/análisis , Plantas , Árboles/fisiología , Monoterpenos/análisis
16.
Nanomaterials (Basel) ; 13(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37947676

RESUMEN

The fast rise of organic pollution has posed severe health risks to human beings and toxic issues to ecosystems. Proper disposal toward these organic contaminants is significant to maintain a green and sustainable development. Among various techniques for environmental remediation, advanced oxidation processes (AOPs) can non-selectively oxidize and mineralize organic contaminants into CO2, H2O, and inorganic salts using free radicals that are generated from the activation of oxidants, such as persulfate, H2O2, O2, peracetic acid, periodate, percarbonate, etc., while the activation of oxidants using catalysts via Fenton-type reactions is crucial for the production of reactive oxygen species (ROS), i.e., •OH, •SO4-, •O2-, •O3CCH3, •O2CCH3, •IO3, •CO3-, and 1O2. Nanoscale zero-valent iron (nZVI), with a core of Fe0 that performs a sustained activation effect in AOPs by gradually releasing ferrous ions, has been demonstrated as a cost-effective, high reactivity, easy recovery, easy recycling, and environmentally friendly heterogeneous catalyst of AOPs. The combination of nZVI and AOPs, providing an appropriate way for the complete degradation of organic pollutants via indiscriminate oxidation of ROS, is emerging as an important technique for environmental remediation and has received considerable attention in the last decade. The following review comprises a short survey of the most recent reports in the applications of nZVI participating AOPs, their mechanisms, and future prospects. It contains six sections, an introduction into the theme, applications of persulfate, hydrogen peroxide, oxygen, and other oxidants-based AOPs catalyzed with nZVI, and conclusions about the reported research with perspectives for future developments. Elucidation of the applications and mechanisms of nZVI-based AOPs with various oxidants may not only pave the way to more affordable AOP protocols, but may also promote exploration and fabrication of more effective and sustainable nZVI materials applicable in practical applications.

17.
Int J Biol Macromol ; 236: 123956, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36898462

RESUMEN

Conducting polymer hydrogels have emerged as promising materials to fabricate highly sensitive strain sensors. However, due to weak bindings between conducting polymer and gel network, they usually suffer from limited stretchability and large hysteresis, failing to achieve wide-range strain sensing. Herein, we combine hydroxypropyl methyl cellulose (HPMC), poly (3,4-ethylenedioxythiophene):poly (styrene sulfonic acid) (PEDOT: PSS) with chemically cross-linked polyacrylamide (PAM) to prepare a conducting polymer hydrogel for strain sensors. Owing to abundant hydrogen bonds between HPMC, PEDOT:PSS and PAM chains, this conducting polymer hydrogel exhibits high tensile strength (166 kPa), ultra-stretchability (>1600 %) and low hysteresis (<10 % at 1000 % cyclic tensile strain). The resultant hydrogel strain sensor shows ultra-high sensitivity, wide strain sensing ranges of 2-1600 %, and excellent durability and reproducibility. Finally, this strain sensor can be used as wearable sensor to monitor vigorous human movement and fine physiological activity, and services as bioelectrodes for electrocardiograph and electromyography monitoring. This work provides new horizons to design conducting polymer hydrogels for advanced sensing devices.


Asunto(s)
Hidrogeles , Dispositivos Electrónicos Vestibles , Humanos , Derivados de la Hipromelosa , Reproducibilidad de los Resultados , Polímeros , Metilcelulosa , Conductividad Eléctrica
18.
Genes (Basel) ; 14(1)2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36672958

RESUMEN

The domain of unknown function 668 (DUF668) is a gene family that plays a vital role in responses to adversity coercion stresses in plant. However, the function of the DUF668 gene family is not fully understood in sweet potato. In this study, bioinformatics methods were used to analyze the number, physicochemical properties, evolution, structure, and promoter cis-acting elements of the IbDUF668 family genes, and RNA-seq and qRT-PCR were performed to detect gene expression and their regulation under hormonal and abiotic stress. A total of 14 IbDUF668 proteins were identified in sweet potato, distributed on nine chromosomes. By phylogenetic analysis, IbDUF668 proteins can be divided into two subfamilies. Transcriptome expression profiling revealed that many genes from DUF668 in sweet potato showed specificity and differential expression under cold, heat, drought, salt and hormones (ABA, GA3 and IAA). Four genes (IbDUF668-6, 7, 11 and 13) of sweet potato were significantly upregulated by qRT-PCR under ABA, drought and NaCl stress. Results suggest that the DUF668 gene family is involved in drought and salt tolerance in sweet potato, and it will further provide the basic information of DUF668 gene mechanisms in plants.


Asunto(s)
Ipomoea batatas , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Sequías , Filogenia , Estrés Fisiológico/genética , Tolerancia a la Sal/genética
19.
Front Plant Sci ; 14: 1136709, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37008495

RESUMEN

Drought is a common environmental stress with great negative impacts on plant growth, development and geographical distribution as well as agriculture and food production. Sweet potato is characterized by starchy, fresh and pigmented tuber, and is regarded as the seventh most important food crop. However, there has been no comprehensive study of the drought tolerance mechanism of different sweet potato cultivars to date. Here, we studied the mechanism for drought response of seven sweet potato drought-tolerant cultivars using the drought coefficients, physiological indicators and transcriptome sequencing. The seven sweet potato cultivars were classified into four groups of drought tolerance performance. A large number of new genes and transcripts were identified, with an average of about 8000 new genes per sample. Alternative splicing events in sweet potato, which were dominated by first exon and last exon alternative splicing, were not conserved among different cultivars and not significantly affected by drought stress. Furthermore, different drought-tolerance mechanisms were revealed through differentially expressed gene analysis and functional annotation. Two drought-sensitive cultivars, Shangshu-9 and Xushu-22, mainly resisted drought stress by up-regulating plant signal transduction. The other drought-sensitive cultivar Jishu-26 responded to drought stress by down-regulating isoquinoline alkaloid biosynthesis and nitrogen/carbohydrate metabolism. In addition, the drought-tolerant cultivar Chaoshu-1 and drought-preferred cultivar Z15-1 only shared 9% of differentially expressed genes, as well as many opposite metabolic pathways in response to drought. They mainly regulated flavonoid and carbohydrate biosynthesis/metabolism in response to drought, while Z15-1 increased photosynthesis and carbon fixation capacity. The other drought-tolerant cultivar Xushu-18 responded to drought stress by regulating the isoquinoline alkaloid biosynthesis and nitrogen/carbohydrate metabolism. The extremely drought-tolerant cultivar Xuzi-8 was almost unaffected by drought stress and responded to drought environment only by regulating the cell wall. These findings provide important information for the selection of sweet potatoes for specific purposes.

20.
Front Microbiol ; 14: 1264939, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38192286

RESUMEN

Introduction: As tick-borne diseases rise to become the second most prevalent arthropod-transmitted disease globally, the increasing investigations focus on ticks correspondingly. Factors contributed to this increase include anthropogenic influences, changes in vertebrate faunal composition, social-recreational shifts, and climatic variation. Employing the 16S gene sequence method in next-generation sequencing (NGS) allows comprehensive pathogen identification in samples, facilitating the development of refined approaches to tick research omnidirectionally. Methods: In our survey, we compared the microbial richness and biological diversity of ticks in Wuwei City, Gansu province, differentiating between questing ticks found in grass and parasitic ticks collected from sheep based on 16S NGS method. Results: The results show Rickettsia, Coxiella, and Francisella were detected in all 50 Dermacentor nuttalli samples, suggesting that the co-infection may be linked to specific symbiotic bacteria in ticks. Our findings reveal significant differences in the composition and diversity of microorganisms, with the Friedmanniella and Bordetella genera existing more prevalent in parasitic ticks than in questing ticks (p < 0.05). Additionally, the network analysis demonstrates that the interactions among bacterial genera can be either promotive or inhibitive in ticks exhibiting different lifestyles with the correlation index |r| > 0.6. For instance, Francisella restrains the development of 10 other bacteria in parasitic ticks, whereas Phyllobacterium and Arthrobacter enhance colonization across all tick species. Discussion: By leveraging NGS techniques, our study reveals a high degree of species and phylogenetic diversity within the tick microbiome. It further highlights the potential to investigate the interplay between bacterial genera in both parasitic and questing ticks residing in identical habitat environments.

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