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1.
Light Sci Appl ; 13(1): 97, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38670946

RESUMEN

Optical sensors with in-cell logic and memory capabilities offer new horizons in realizing machine vision beyond von Neumann architectures and have been attempted with two-dimensional materials, memristive oxides, phase-changing materials etc. Noting the unparalleled performance of superconductors with both quantum-limited optical sensitivities and ultra-wide spectrum coverage, here we report a superconducting memlogic long-wave infrared sensor based on the bistability in hysteretic superconductor-normal phase transition. Driven cooperatively by electrical and optical pulses, the device offers deterministic in-sensor switching between resistive and superconducting (hence dissipationless) states with persistence > 105 s. This results in a resilient reconfigurable memlogic system applicable for, e.g., encrypted communications. Besides, a high infrared sensitivity at 12.2 µm is achieved through its in-situ metamaterial perfect absorber design. Our work opens the avenue to realize all-in-one superconducting memlogic sensors, surpassing biological retina capabilities in both sensitivity and wavelength, and presents a groundbreaking opportunity to integrate visional perception capabilities into superconductor-based intelligent quantum machines.

2.
Sci Rep ; 14(1): 5257, 2024 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-38438470

RESUMEN

Nuclear factor Y (NF-Y) gene family is an important transcription factor composed of three subfamilies of NF-YA, NF-YB and NF-YC, which is involved in plant growth, development and stress response. In this study, 63 tobacco NF-Y genes (NtNF-Ys) were identified in Nicotiana tabacum L., including 17 NtNF-YAs, 30 NtNF-YBs and 16 NtNF-YCs. Phylogenetic analysis revealed ten pairs of orthologues from tomato and tobacco and 25 pairs of paralogues from tobacco. The gene structure of NtNF-YAs exhibited similarities, whereas the gene structure of NtNF-YBs and NtNF-YCs displayed significant differences. The NtNF-Ys of the same subfamily exhibited a consistent distribution of motifs and protein 3D structure. The protein interaction network revealed that NtNF-YC12 and NtNF-YC5 exhibited the highest connectivity. Many cis-acting elements related to light, stress and hormone response were found in the promoter of NtNF-Ys. Transcriptome analysis showed that more than half of the NtNF-Y genes were expressed in all tissues, and NtNF-YB9/B14/B15/B16/B17/B29 were specifically expressed in roots. A total of 15, 12, 5, and 6 NtNF-Y genes were found to respond to cold, drought, salt, and alkali stresses, respectively. The results of this study will lay a foundation for further study of NF-Y genes in tobacco and other Solanaceae plants.


Asunto(s)
Nicotiana , Solanaceae , Nicotiana/genética , Filogenia , Factor de Unión a CCAAT/genética
3.
Nat Commun ; 14(1): 3046, 2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37236987

RESUMEN

Broken symmetries play a fundamental role in superconductivity and influence many of its properties in a profound way. Understanding these symmetry breaking states is essential to elucidate the various exotic quantum behaviors in non-trivial superconductors. Here, we report an experimental observation of spontaneous rotational symmetry breaking of superconductivity at the heterointerface of amorphous (a)-YAlO3/KTaO3(111) with a superconducting transition temperature of 1.86 K. Both the magnetoresistance and superconducting critical field in an in-plane field manifest striking twofold symmetric oscillations deep inside the superconducting state, whereas the anisotropy vanishes in the normal state, demonstrating that it is an intrinsic property of the superconducting phase. We attribute this behavior to the mixed-parity superconducting state, which is an admixture of s-wave and p-wave pairing components induced by strong spin-orbit coupling inherent to inversion symmetry breaking at the heterointerface of a-YAlO3/KTaO3. Our work suggests an unconventional nature of the underlying pairing interaction in the KTaO3 heterointerface superconductors, and brings a new broad of perspective on understanding non-trivial superconducting properties at the artificial heterointerfaces.

4.
Opt Express ; 31(5): 7440-7449, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859874

RESUMEN

Superconducting photodetection offers a wide spectral coverage ranging from the microwave to X-ray, and in the short wavelength range, single photon sensitivity can be achieved. However, in the longer wavelength infrared region, the system detection efficiency is low due to the lower internal quantum efficiency and weak optical absorption. Here, we utilized the superconducting metamatieral to enhance the light coupling efficiency and reach nearly perfect absorption at dual color infrared wavelengths. Dual color resonances arise from hybridization of local surface plasmon mode of the metamaterial structure and the Fabry-Perot-like cavity mode of metal (Nb)-dielectric (Si)-metamatieral (NbN) tri-layer structure. We demonstrated that, at the working temperature of 8 K slightly below TC ∼8.8 K, this infrared detector exhibits the peak responsivity of 1.2 × 106V/W and 3.2 × 106V/W at two resonant frequencies 36.6 THz and 104 THz, respectively. The peak responsivity is enhanced about ∼8 and ∼22 times, respectively, compared to that of non-resonant frequency (67 THz). Our work provides a way to harvest infrared light efficiently and hence improve the sensitivity of superconducting photodetectors in multispectral infrared range, which may find promising applications in thermal image and gas sensing etc.

5.
Eur J Cancer Care (Engl) ; 31(6): e13620, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35612356

RESUMEN

OBJECTIVE: This meta-analysis aims to compare the effects of early palliative care on patients with incurable cancer with those of standard oncologic care or on-demand palliative care. METHODS: Pubmed, Embase, Web of Science, Cochrane Library, ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform (ICTRP) were searched for relevant randomised controlled trials. We also screened reference lists of included studies for additional qualified studies. We used Cochrane Collaboration Risk of Bias Tool to evaluate quality of included studies. DerSimonian and Laird's random effects meta-analysis was used to synthesise the effects. RESULTS: Sixteen in 1376 studies were included. The pooled data suggested that patients receiving early palliative care had better quality of life (SMD = 0.737, 95% CI: 0.240-1.234), fewer symptoms (SMD = 0.304, 95% CI: 0.097-0.510), better mood (SMD = -0.443, 95% CI: -0.605 to -0.282), better survival (hazard ratio [HR] of death: HR = 1.521, 95% CI: 1.521-1.923; 1-year overall survival probability: HR = 1.238, 95% CI: 1.031-1.486) and higher probability of dying at home (HR = 1.153, 95% CI: 1.027-1.295) than patients in the control group. And there is no difference between resource use. CONCLUSION: Early palliative care improves lives of patients with incurable cancer, but the evidence level is low because of high heterogeneity of quality of life and small numbers of included studies for other results.


Asunto(s)
Enfermería de Cuidados Paliativos al Final de la Vida , Neoplasias , Humanos , Neoplasias/terapia , Cuidados Paliativos , Calidad de Vida
6.
Int J Immunopathol Pharmacol ; 36: 20587384211063962, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34986036

RESUMEN

BACKGROUND: Modern pharmacological studies have shown that traditional Chinese medicine (TCM) Taraxacum mongolicum possesses anti-cancer activity. Taraxerol (TRX) is a pentacyclic triterpene isolated from T. mongolicum, which is widely used in clinical treatment, and its anti-cancer effects have been extensively studied. However, the effects and molecular mechanism of TRX in gastric cancer (GC) have not been fully explicated. METHODS: We used public databases to derive information on potential targets of TRX and proteins related to GC. Also, STRING and R3.6.2 software were used to analyze the protein-protein interaction (PPI). The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were done to explain the potential mechanism underlying the regulatory role of TRX in GC. The role of TRX in GC was verified by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay, apoptosis analysis, Transwell assay, and wound healing assay, and the key signaling pathways were verified. RESULTS: We identified 135 potential targets for the treatment of GC via network pharmacological analysis. GO and KEGG enrichment analysis showed that steroid hormone receptor activity and the PI3K/AKT signaling pathway were the biological processes and pathways with the highest degree of enrichment. Additionally, cellular experiments revealed that TRX inhibited the proliferation, migration, and invasion of GC cells as well as induced G1 phase arrest and apoptosis in GC cells. CONCLUSION: Here, we used multi-target and multi-pathway network pharmacological analysis to verify the anti-cancer activity of TRX in GC. Also, in vitro experimental data were used to derive the potential molecular mechanism.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Ácido Oleanólico/análogos & derivados , Neoplasias Gástricas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Farmacología en Red , Ácido Oleanólico/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Mapas de Interacción de Proteínas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
7.
Front Oncol ; 11: 711984, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34540679

RESUMEN

BACKGROUND: Pogostemon cablin is a traditional Chinese medicine (TCM) that is frequently used to treat various gastrointestinal diseases. Patchouli alcohol (PA), a compound extracted from the Pogostemon cablin, has been shown to have anti-tumor efficacy in human colorectal cancer. However, the mechanism of PA's anticancer effect on gastric cancer (GC) remains unknown. METHODS: We used the public database to obtain the potential targets of PA and genes related to GC. Bioinformatic analyses, such as the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and protein-protein interactions (PPI), were used for analyzing the potential signal pathways and targets. Cell experiments were also conducted to further explain the impact and molecular mechanism of PA on GC, as well as to confirm the findings of network pharmacology. RESULTS: Using network pharmacological analysis, 161 possible targets were identified for the treatment of GC. Network analysis and functional enrichment analysis show that PA produced a marked effect in the treatment of GC through multi-targets and multi-pathways, especially the MAPK and PI3K/AKT signal pathways. In addition, PA showed the inhibition of GC cell proliferation, migration and invasion in cell experiments. According to our findings, PA could also cause G0/G1 phase arrest and apoptosis in GC cells. CONCLUSION: Using network pharmacology, we aim to uncover the possible molecular mechanism of PA on GC treatment in this research. Cell experiments were also conducted to confirm the therapeutic effect of PA on GC.

8.
Biomed Chromatogr ; 35(8): e5116, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33724505

RESUMEN

Qianjinweijing Tang (QJWJ) is a classic traditional Chinese formula that is often used in the treatment of treat lung cancer (LC). However, the underlying cellular mechanisms of the anticancer effects of QJWJ remain unclear. Cell viability was determined by MTS assay and levels of apoptosis measured by flow cytometry. Animal experiments were conducted to determine the effects of QJWJ on tumor growth in vivo. We used a proteomics approach to study the effects of QJWJ on LC cells and applied bioinformatics analysis to identify differentially expressed proteins that were validated by western blotting. QJWJ inhibited the proliferation of LC cells and induced apoptosis. The tumor growth delay effects of QJWJ were confirmed in vivo. We identified 104 differentially expressed proteins following QJWJ treatments of which 45 proteins were upregulated and 59 were downregulated. The levels of differentially expressed proteins were validated by western blotting. Our study indicated that QJWJ has anticancer effects in vivo and in vitro and that these effects are mediated by modulating the expression of tumor-related proteins.


Asunto(s)
Antineoplásicos , Medicamentos Herbarios Chinos , Neoplasias Pulmonares/metabolismo , Proteoma/efectos de los fármacos , Proteómica/métodos , Células A549 , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Humanos , Ratones , Ratones Endogámicos BALB C , Proteoma/análisis , Espectrometría de Masas en Tándem , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Environ Technol ; 41(15): 1937-1949, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30472931

RESUMEN

Particulate Matters such as PM10, PM2.5 may contain heavy metal oxides and harmful substances that threaten human health and environmental quality. In this paper, we propose a new combined neural network algorithm which based on Elman, echo state network (ESN) and cascaded BP neural network (CBP) to predict PM10 and PM2.5. In order to further improve the performance of the prediction result, we use the simulated annealing algorithm (SA) to optimize the parameters in the combination method to form the optimal combination model. And particle swarm optimization (PSO) is used to optimize the parameters in ESN. The chemical species in the atmosphere which include SO2, NO, NO2, O3 and CO in Baiyin, Gansu Province of China are used to test and verify the proposed combined method. The experimental results show that the prediction performance of the combined model presented in this paper is indeed superior to other three neural network models.


Asunto(s)
Contaminantes Atmosféricos , Metales Pesados , China , Humanos , Redes Neurales de la Computación , Material Particulado
10.
Sci Rep ; 6: 22713, 2016 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-26936470

RESUMEN

We present a two-step technique for the synthesis of superconducting CuxBi2Se3. Cu0.15Bi2Se3 single crystals were synthesized using the melt-growth method. Although these samples are non-superconducting, they can be employed to generate high quality superconducting samples if used as precursors in the following electrochemical synthesis step. Samples made from Cu0.15Bi2Se3 reliably exhibit zero-resistance even under the non-optimal quenching condition, while samples made from pristine Bi2Se3 require fine tuning of the quenching conditions to achieve similar performance. Moreover, under the optimal quenching condition, the average superconducting shielding fraction was still lower in the samples made from pristine Bi2Se3 than in the samples made from Cu0.15Bi2Se3. These results suggest that the pre-doped Cu atoms facilitate the formation of a superconducting percolation network. We also discuss the useful clues that we gathered about the locations of Cu dopants that are responsible for superconductivity.

11.
Artículo en Chino | MEDLINE | ID: mdl-15627683

RESUMEN

Lignin, one of the main components in vascular plants, is important for the adaptation of terrestrial plants to environment during evolution. However, its presence in plants has negative effects on wood processing during pulping and stock breeding. Therefore much attention has been focused on the regulation of lignin biosynthesis. The pathways leading to the synthesis of lignin polymers have been studied for decades. Much understanding of lignin biosynthesis has been advanced. This paper reviewed the recent progress made in the various steps associated with monolignol biosynthesis. It includes the catalysis by three enzymes, i.e. p-coumarate-3-hydroxylase (C3H), ferulate-5-hydroxylase (F5H) and caffeic acid 3-O-methyltransferase (COMT); the multiform biosynthetic pathway of syringyl (S) lignin in angiosperms; the biosynthesis route of guaiacyl (G) and syringyl (S) lignin specifically regulated by cinnamyl alcohol dehydrogenase (CAD) and sinapyl alcohol dehydrogenase (SAD) and the formation of the lignin macromolecule. Based on the elucidation of lignin biosynthesis pathway, it has also been given the achievements in lignin gene engineering. Many studies were concentrated on the modification of lignin content and composition. In some cases, the potential value of transgenic plants with modified lignin beneficial for pulping has been demonstrated. To better understand the mechanism of lignin biosynthesis and improve the properties of plants, new biotechnological strategies can be developed, which include combinatorial modification of multiple lignin traits in plants through multigene cotransformation, transcriptional control of lignin biosynthesis and the application of RNA interference. The identification of novel genes by molecular and genetic approaches will be useful in opening up new avenues of lignin modification in the future.


Asunto(s)
Ingeniería Genética , Lignina/biosíntesis , Interferencia de ARN , Transcripción Genética
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