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1.
Front Genet ; 15: 1362420, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601076

RESUMO

Objective: Recent studies have revealed increasing evidence that the long non-coding RNA bladder cancer associated transcript 1 (LncRNA BLACAT1) plays an essential role in the emergence of different malignancies. This meta-analysis aimed to evaluate the prognostic significance of LncRNA BLACAT1 in various cancers. Methods: Six electronic databases (PubMed, Embase, Medline, Web of Science, China National Knowledge Infrastructure (CNKI), and the Chinese WanFang database) were comprehensively searched for relevant studies. The analysis of overall survival (OS) and clinicopathological characteristics was conducted. Results: Nineteen studies with 1,559 patients were eventually eligible to be included in this meta-analysis. High expression level of LncRNA BLACAT1 was identified to be linked with shorter OS (HR: 2.02, 95% CI: 1.66-2.46, p < 0.001) and PFS (HR: 2.424, 95% CI: 1.827-3.020, p < 0.001) in cancer patients as opposed to low expression levels. Subgroup analysis showed that analysis model (multivariate or univariate), cut-off value (mean or median), sample size (more or fewer than 100), and cancer type had little effect on OS in multiple tumors. Moreover, high LncRNA BLACAT1 expression was associated with positive lymph node metastasis (HR: 2.29, 95% CI: 1.66-3.16, p < 0.00001), advanced clinical stage (HR: 2.29, 95% CI: 1.65-3.19, p < 0.00001) and worse differentiation status (HR: 0.58, 95% CI: 0.37-0.92, p = 0.02), compared to low LncRNA BLACAT1 expression. Conclusion: The findings highlight that high LncRNA BLACAT1 expression might be detrimental and induce a worse prognosis for cancer patients.

2.
Front Pharmacol ; 15: 1321405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560355

RESUMO

Backgroud: The co-administration of Chinese patent medicine with calcium channel blockers (CCBs) is a prevalent practice in China for treating essential hypertension (EH). However, robust evidence supporting the efficacy and safety of tailored combinations of different Chinese patent medicines with CCBs, according to individual patient conditions, is still limited. This study sought to elucidate the efficacy and safety of these combinations using a systematic review and network meta-analysis. Materials and methods: Relevant studies were sourced from established databases, incorporating randomized controlled trials published up to 1 February 2023. The ROB2 tool from the Cochrane Collaborative Network was employed to independently assess and cross-verify the quality of the included literature. A network meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) 2020 and PRISMA-Network Meta-Analyses (PRISMA-NMA) guidelines. A Bayesian network meta-analysis was utilized to gauge the efficacy and safety of distinct integrations of Chinese patent medicine and CCBs. Primary outcomes were interpreted using a paired fixed-effect meta-analysis. Publication bias was appraised through Egger's test and represented with funnel plots. All statistical analyses were executed within the R statistical framework. Results: Following rigorous selection, data extraction, and bias evaluation, 36 articles were incorporated. Tianma Gouteng Granule, when combined with CCBs, displayed superior efficacy in reducing systolic blood pressure (SBP). In terms of diastolic blood pressure (DBP) reduction, Songling Xuemaikang Capsule combined with CCBs emerged as the most effective. Regarding enhancement of antihypertensive effective rates, Qinggan Jiangya Capsule paired with CCBs demonstrated optimal results. For diminishing Traditional Chinese Medicine syndrome scores, the Qiangli Dingxuan Tablet and CCBs combination proved most beneficial. When aiming to reduce total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) levels, Tianma Gouteng Granule and CCBs showcased superior results. In contrast, the combination of Songling Xuemaikang Capsule and CCBs was more effective in reducing LDL-C, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Conclusion: This study underscores variability in outcomes from combining Chinese patent medicine and CCBs for hypertension, emphasizing the importance of personalized medicinal combinations, especially Tianma Gouteng Granule and Songling Xuemaikang Capsule. The results offer robust evidence to inform clinical guidelines for essential hypertention and significantly aid clinician in seleting appropriate Chinese patent medicines for treatment.

3.
Front Chem ; 12: 1356458, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38496269

RESUMO

Background: With the increasing global prevalence of hypertension, a condition that can severely affect multiple organs, there is a growing need for effective treatment options. Uncaria rhynchophylla-Alisma plantago-aquatica L. (UR-AP) is a traditional drug pair used for treating hypertension based on the liver-kidney synergy concept. However, the detailed molecular mechanisms underlying its efficacy remain unclear. Methods: This study utilized an integrative approach combining network pharmacology, cluster analysis, and molecular docking to uncover the bioactive components and targets of UR-AP in the treatment of hypertension. Initially, we extracted data from public databases to identify these components and targets. A Protein-Protein Interaction (PPI) network was constructed, followed by enrichment analysis to pinpoint the bioactive components, core targets, and pivotal pathways. Cluster analysis helped in identifying key sub-networks and hypothesizing primary targets. Furthermore, molecular docking was conducted to validate the interaction between the core targets and major bioactive components, thus confirming their potential efficacy in hypertension treatment. Results: Network pharmacological analysis identified 58 bioactive compounds in UR-AP, notably quercetin, kaempferol, beta-sitosterol (from Uncaria rhynchophylla), and Alisol B, alisol B 23-acetate (from Alisma plantago-aquatica L.), as pivotal bioactives. We pinpointed 143 targets common to both UR-AP and hypertension, highlighting MAPK1, IL6, AKT1, VEGFA, EGFR, and TP53 as central targets involved in key pathways like diastolic and endothelial function, anti-atherosclerosis, AGE-RAGE signaling, and calcium signaling. Cluster analysis emphasized IL6, TNF, AKT1, and VEGFA's roles in atherosclerosis and inflammation. Molecular docking confirmed strong interactions between these targets and UR-AP's main bioactives, underscoring their therapeutic potential. Conclusion: This research delineates UR-AP's pharmacological profile in hypertension treatment, linking traditional medicine with modern pharmacology. It highlights key bioactive components and their interactions with principal targets, suggesting UR-AP's potential as a novel therapeutic option for hypertension. The evidence from molecular docking studies supports these interactions, indicating the relevance of these components in affecting hypertension pathways. However, the study acknowledges its limitations, including the reliance on in silico analyses and the need for in vivo validation. These findings pave the way for future clinical research, aiming to integrate traditional medicine insights with contemporary scientific approaches for developing innovative hypertension therapies.

4.
ACS Nano ; 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38315444

RESUMO

Correlating the microscopic structural characteristics with the macroscopic electrochemical performance in electrode materials is critical for developing excellent-performance lithium-ion batteries, which however remains largely unexplored. Here, we show that the Zn2SnO4 (ZTO) nanowires (NWs) with smaller diameters (d < 5 nm) exhibit slower capacity fade rate and better cycling stability, as compared with the NWs with larger diameters ranging from tens to hundreds of nanometers. By applying in situ transmission electron microscopy (TEM), we discover a strong correlation of cracking behavior with the NW diameter. Upon the first lithiation, there exists a critical diameter of ∼80 nm, below which the NWs neither crack nor fracture, and above which the cracks could easily nucleate and propagate along the specific planes, resulting in the deteriorated cycling stability in larger sized electrodes. Further theoretical calculations based on the finite element model and the climbing image nudged elastic band method faithfully predict the size-dependent cracking behaviors, which may result from the synergistic effect of axial stress evolution as well as preferential Li-ion migration directions during the first lithiation. This work provides a real-time tracking of the tempo-spatial structural evolution of a single ZTO NW, which facilitates a fundamental understanding of how the sample size affects the electrochemical behavior and thus offers a reference for future battery design and application strategy.

5.
J Phys Chem Lett ; 14(49): 11152-11159, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38054437

RESUMO

Unveiling the effects of oxygen vacancies on the structural stability of layered α-MoO3 is critical for optimizing its physical and chemical properties. Herein, we present experimental evidence regarding the phase stability of α-MoO3 with ∼2% oxygen vacancy concentrations. Interestingly, we report a previously ignored oxygen-deficient orthorhombic MoO3-x phase in space group Cmcm. Further density functional theory calculations reveal a detailed phase transition mechanism from α-MoO3 to MoO3-x. More importantly, we demonstrate that two-dimensional (2D) large polarons must exist to stabilize the MoO3-x crystal structure. 2D large polarons are suspected to exist in numerous quasi-2D systems but have never been found in layered α-MoO3 or other molybdenum oxides. Our work contributes to a basic understanding of the polaronic behavior in MoO3-x and may broaden the application realm of molybdenum oxides.

6.
Int J Clin Pract ; 2023: 9504108, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38146345

RESUMO

Objectives: Management of chronic coronary syndrome (CCS) encompasses a broad spectrum of practices, posing considerable complexity and variability. While guidelines have been established to augment the management quality of CCS, notable disparities persist across their recommendations. This study strives to scrutinize, compare, and reconcile these guideline recommendations pertaining to the diagnosis, treatment, and management of CCS patients. Our goal is to align these recommendations with contemporary clinical practices, thus laying a robust foundation for their pragmatic application in clinical settings. Methods: A comprehensive systematic search was conducted across multiple databases, including PubMed, EMBASE, China National Knowledge Infrastructure, Wanfang Database, China Science and Technology Journal Database, Chinese Biomedical Literature Service System, Chinese Science and Technology Periodical Database, and Chinese Biological Medicine Database. The timeframe for this search spanned from their inception up to May 30, 2022, aiming to collate all published guidelines relevant to CCS. Subsequently, two independent reviewers undertook the task of appraising the quality of these guidelines by utilizing the Appraisal of Guidelines for Research and Evaluation II instrument. Results: The search yielded a total of 10,699 citations. Following a thorough evaluation, fourteen clinical practice guidelines and four consensus statements, each offering specific recommendations for CCS, were selected. The quality of these guidelines showcased a broad spectrum of variation. The domain of "presentation clarity" received the highest accolades, while "applicability" languished at the lower end of the scoring spectrum. On average, the guidelines attained a quality score denoting sufficiency. Furthermore, recommendations across different guidelines for the diagnosis, treatment, and management of CCS displayed a striking level of divergence. Conclusion: The landscape of published CCS guidelines is marked by extensive variations in scope, quality, and recommendations. Hence, there is a compelling need for collaborative efforts amongst multidisciplinary professionals to forge comprehensive, higher-quality evidence-based guidelines; such a concerted approach is paramount to enhance treatment efficacy and health outcomes for patients grappling with CCS.


Assuntos
Resultado do Tratamento , Humanos , China , Consenso , Bases de Dados Factuais , Guias de Prática Clínica como Assunto
7.
Inorg Chem ; 62(49): 20096-20104, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38011516

RESUMO

In our pursuit of promoting the green development of energetic materials and harnessing their functional benefits, we strive to address the inherent contradiction between energy and low sensitivity. In this regard, we have successfully constructed an azotriazole framework via environmentally friendly electrochemistry with a satisfactory yield of 62.3%. Through a simple ion-exchange process, we then synthesized nitrogen-rich salt derivatives of azotriazolone. These nitrogen-rich salts exhibit a wide range of nitrogen contents, ranging from 32.16 to 68.80%. Remarkably, crystallographic analysis of these green energy-containing salts reveals substantial advantages in terms of thermodynamic stability and low sensitivity. Experimental investigations have demonstrated a positive relationship between the nitrogen content and the pyrothermal performance of the azotriazolone derivatives. Of particular significance is compound 5, a triaminoguanidine salt, which exhibits an exceptionally high nitrogen content of 68.80%. It displays a detonation pressure of 28.2 GPa and a detonation velocity of 7939.4 m s-1. Moreover, the derivatives of azotriazolone salts demonstrate the formation of nitrogen-rich compounds, characterized by insensitive properties, attributed to the hydrogen-bonded network structures resulting from anion-cation interactions. With the exception of compound 5, which exhibits a friction sensitivity of 252 N, the remaining derivatives show a similar value of approximately 360 N. This suggests that azotriazolone serves as a promising material possessing both stabilizing properties and better detonation performance, thereby providing a favorable platform for the synthesis of novel compounds with advantageous properties.

8.
Nano Lett ; 23(16): 7364-7370, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37530420

RESUMO

Gallium oxide (Ga2O3) has attracted extensive attention as a potential candidate for low-dimensional metal-oxide-semiconductor field-effect transistors (MOSFETs) due to its wide bandgap, controllable doping, and low cost. The structural stability of nanoscale Ga2O3 is the key parameter for designing and constructing a MOSFET, which however remains unexplored. Using in situ transmission electron microscopy, we reveal the size-dependent phase transition of sub-2 nm Ga2O3 nanowires. Based on theoretical calculations, the transformation pathways from the initial monoclinic ß-phase to an intermediate cubic γ-phase and then back to the ß-phase have been mapped and identified as a sequence of Ga cation migrations. Our results provide fundamental insights into the Ga2O3 phase stability within the nanoscale, which is crucial for advancing the miniaturization, light weight, and integration of wide-bandgap semiconductor devices.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37027253

RESUMO

OBJECTIVE: The key principle of motor imagery (MI) decoding for electroencephalogram (EEG)-based Brain-Computer Interface (BCI) is to extract task-discriminative features from spectral, spatial, and temporal domains jointly and efficiently, whereas limited, noisy, and non-stationary EEG samples challenge the advanced design of decoding algorithms. METHODS: Inspired by the concept of cross-frequency coupling and its correlation with different behavioral tasks, this paper proposes a lightweight Interactive Frequency Convolutional Neural Network (IFNet) to explore cross-frequency interactions for enhancing representation of MI characteristics. IFNet first extracts spectro-spatial features in low and high-frequency bands, respectively. Then the interplay between the two bands is learned using an element-wise addition operation followed by temporal average pooling. Combined with repeated trial augmentation as a regularizer, IFNet yields spectro-spatio-temporally robust features for the final MI classification. We conduct extensive experiments on two benchmark datasets: the BCI competition IV 2a (BCIC-IV-2a) dataset and the OpenBMI dataset. RESULTS: Compared with state-of-the-art MI decoding algorithms, IFNet achieves significantly superior classification performance on both datasets while improving the winner's result in BCIC-IV-2a by 11%. Moreover, by conducting sensitivity analysis on decision windows, we show IFNet attains the best trade-off between decoding speed and accuracy. Detailed analysis and visualization verify IFNet can capture the coupling across frequency bands along with the known MI signatures. CONCLUSION: We demonstrate the effectiveness and superiority of the proposed IFNet for MI decoding. SIGNIFICANCE: This study suggests IFNet holds promise for rapid response and accurate control in MI-BCI applications.


Assuntos
Interfaces Cérebro-Computador , Imaginação , Humanos , Imaginação/fisiologia , Redes Neurais de Computação , Algoritmos , Eletroencefalografia
10.
Small ; 18(42): e2204346, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36055773

RESUMO

The fiber-shaped aqueous battery (FSAB) has the advantages of flexibility, portability and safety making it promising for energy storage applications. In particular, FSABs based on metal wire current collectors with good electrical conductivity can provide excellent energy storage properties. However, the low adhesion caused by the smooth surface of the metal wire and the unavailability of many electrochemically active materials for use in FSAB is holding back their development. Herein, a substrate is effectively constructed for the strongly applicable growth of the active material via a Ni wire etching strategy. In addition, core-shell structured nanorod arrays consisting of NiCo2 O4 and Ni-metal-organic frameworks (MOFs) are constructed, where Ni-MOF can be obtained rapidly via ß-Ni(OH)2 intermediates. The NCO/NM-15 electrode obtained by structural regulation exhibits high capacity and outstanding cycling stability. De calculations further demonstrate that the formation of NiCo2 O4 and Ni-MOF heterostructures results in a significant increase in the Fermi level leading to more active internal electrons, which facilitates electron transfer in electrochemical reactions. An assembled FSAB device can provide an energy density of 158.33 µWh cm-2 and the devices can provide power for a calculator and an electronic watch screen, demonstrating a wide application prospect in the field of energy storage.

11.
Appl Opt ; 61(31): 9107-9111, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607043

RESUMO

The temporal resolution uniformity of a time-dilation framing camera is studied, and the ideal photocathode (PC) pulse curve is determined, while the temporal magnification factor is kept constant. To obtain the ideal curve, a series of linear pulses with the same slope are superposed. The variance in the temporal resolution and the number of linear pulses required are compared, while the superposition results with different slopes are used as the PC voltage. As the slope of the linear pulses decreases, the variance decreases, which means that the uniformity of the temporal resolution is improved, but the number of linear pulses required increases. In this study, linear pulses with a slope of 1 V/ps are superposed. Nine linear pulses with a front edge time of 200 ps, amplitude of 200 V, and flat top time of 1 ns are superimposed to approximate the ideal PC pulse curve with a constant temporal magnification factor of 10; the trigger times of the pulses are 0, 0, 0, 185, 200, 350, 450, 605, and 790 ps. When the superposition result is applied as the PC voltage and the measured signal is synchronized to the PC pulse at 128 ps-1 ns, the temporal resolution error is within 5%.

12.
Natl Sci Rev ; 8(9): nwab069, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34691739

RESUMO

With the deployment of fifth-generation (5G) wireless networks worldwide, research on sixth-generation (6G) wireless communications has commenced. It is expected that 6G networks can accommodate numerous heterogeneous devices and infrastructures with enhanced efficiency and security over diverse, e.g. spectrum, computing and storage, resources. However, this goal is impeded by a number of trust-related issues that are often neglected in network designs. Blockchain, as an innovative and revolutionary technology that has arisen in the recent decade, provides a promising solution. Building on its nature of decentralization, transparency, anonymity, immutability, traceability and resiliency, blockchain can establish cooperative trust among separate network entities and facilitate, e.g. efficient resource sharing, trusted data interaction, secure access control, privacy protection, and tracing, certification and supervision functionalities for wireless networks, thus presenting a new paradigm towards 6G. This paper is dedicated to blockchain-enabled wireless communication technologies. We first provide a brief introduction to the fundamentals of blockchain, and then we conduct a comprehensive investigation of the most recent efforts in incorporating blockchain into wireless communications from several aspects. Importantly, we further propose a unified framework of the blockchain radio access network (B-RAN) as a trustworthy and secure paradigm for 6G networking by utilizing blockchain technologies with enhanced efficiency and security. The critical elements of B-RAN, such as consensus mechanisms, smart contract, trustworthy access, mathematical modeling, cross-network sharing, data tracking and auditing and intelligent networking, are elaborated. We also provide the prototype design of B-RAN along with the latest experimental results.

13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 38(3): 447-454, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34180189

RESUMO

Emotion plays an important role in people's cognition and communication. By analyzing electroencephalogram (EEG) signals to identify internal emotions and feedback emotional information in an active or passive way, affective brain-computer interactions can effectively promote human-computer interaction. This paper focuses on emotion recognition using EEG. We systematically evaluate the performance of state-of-the-art feature extraction and classification methods with a public-available dataset for emotion analysis using physiological signals (DEAP). The common random split method will lead to high correlation between training and testing samples. Thus, we use block-wise K fold cross validation. Moreover, we compare the accuracy of emotion recognition with different time window length. The experimental results indicate that 4 s time window is appropriate for sampling. Filter-bank long short-term memory networks (FBLSTM) using differential entropy features as input was proposed. The average accuracy of low and high in valance dimension, arousal dimension and combination of the four in valance-arousal plane is 78.8%, 78.4% and 70.3%, respectively. These results demonstrate the advantage of our emotion recognition model over the current studies in terms of classification accuracy. Our model might provide a novel method for emotion recognition in affective brain-computer interactions.


Assuntos
Memória de Curto Prazo , Redes Neurais de Computação , Nível de Alerta , Eletroencefalografia , Emoções , Humanos
14.
Plant Biotechnol J ; 19(10): 2052-2068, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34042262

RESUMO

Cytosine base editors (CBEs) are great additions to the expanding genome editing toolbox. To improve C-to-T base editing in plants, we first compared seven cytidine deaminases in the BE3-like configuration in rice. We found A3A/Y130F-CBE_V01 resulted in the highest C-to-T base editing efficiency in both rice and Arabidopsis. Furthermore, we demonstrated this A3A/Y130F cytidine deaminase could be used to improve iSpyMacCas9-mediated C-to-T base editing at A-rich PAMs. To showcase its applications, we first applied A3A/Y130F-CBE_V01 for multiplexed editing to generate microRNA-resistant mRNA transcripts as well as pre-mature stop codons in multiple seed trait genes. In addition, we harnessed A3A/Y130F-CBE_V01 for efficient artificial evolution of novel ALS and EPSPS alleles which conferred herbicide resistance in rice. To further improve C-to-T base editing, multiple CBE_V02, CBE_V03 and CBE_V04 systems were developed and tested in rice protoplasts. The CBE_V04 systems were found to have improved editing activity and purity with focal recruitment of more uracil DNA glycosylase inhibitors (UGIs) by the engineered single guide RNA 2.0 scaffold. Finally, we used whole-genome sequencing (WGS) to compare six CBE_V01 systems and four CBE_V04 systems for genome-wide off-target effects in rice. Different levels of cytidine deaminase-dependent and sgRNA-independent off-target effects were indeed revealed by WGS among edited lines by these CBE systems. We also investigated genome-wide sgRNA-dependent off-target effects by different CBEs in rice. This comprehensive study compared 21 different CBE systems, and benchmarked PmCDA1-CBE_V04 and A3A/Y130F-CBE_V04 as next-generation plant CBEs with high editing efficiency, purity, and specificity.


Assuntos
Citosina , Edição de Genes , Sistemas CRISPR-Cas , Mutação , RNA Guia de Cinetoplastídeos , Sequenciamento Completo do Genoma
15.
Nat Commun ; 12(1): 1944, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782402

RESUMO

CRISPR-Cas12a is a promising genome editing system for targeting AT-rich genomic regions. Comprehensive genome engineering requires simultaneous targeting of multiple genes at defined locations. Here, to expand the targeting scope of Cas12a, we screen nine Cas12a orthologs that have not been demonstrated in plants, and identify six, ErCas12a, Lb5Cas12a, BsCas12a, Mb2Cas12a, TsCas12a and MbCas12a, that possess high editing activity in rice. Among them, Mb2Cas12a stands out with high editing efficiency and tolerance to low temperature. An engineered Mb2Cas12a-RVRR variant enables editing with more relaxed PAM requirements in rice, yielding two times higher genome coverage than the wild type SpCas9. To enable large-scale genome engineering, we compare 12 multiplexed Cas12a systems and identify a potent system that exhibits nearly 100% biallelic editing efficiency with the ability to target as many as 16 sites in rice. This is the highest level of multiplex edits in plants to date using Cas12a. Two compact single transcript unit CRISPR-Cas12a interference systems are also developed for multi-gene repression in rice and Arabidopsis. This study greatly expands the targeting scope of Cas12a for crop genome engineering.


Assuntos
Arabidopsis/genética , Proteínas de Bactérias/genética , Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas , Endodesoxirribonucleases/genética , Edição de Genes/métodos , Engenharia Genética/métodos , Genoma de Planta , Oryza/genética , Agrobacterium tumefaciens , Alelos , Arabidopsis/metabolismo , Proteínas de Bactérias/metabolismo , Sequência de Bases , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Proteínas Associadas a CRISPR/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Produtos Agrícolas , Endodesoxirribonucleases/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Oryza/metabolismo , Plantas Geneticamente Modificadas , RNA Guia de Cinetoplastídeos/genética , RNA Guia de Cinetoplastídeos/metabolismo , Alinhamento de Sequência
16.
Sensors (Basel) ; 20(19)2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33019567

RESUMO

In this work, we propose a satellite-aided permissionless consensus protocol for scalable space-terrestrial blockchains. We design its working principle and workflow by taking full advantage of satellites for extensive coverage and ubiquitous connectivity. Based on the proposed protocol, we demonstrate how such a space-terrestrial blockchain grows and evolves through several typical cases in the presence of adversarial nodes, user misbehavior, and transmission outage. Taking proof of work (PoW) as a benchmark, we assess the system security by considering both adversarial miners and possible colluding satellites. Then, we analyze the maximum blockchain throughput under network capacity limits and evaluate the impact of information propagation delay via a Markov model. Simulation results support that the proposed satellite-aided consensus protocol achieves higher throughput and exhibits greater scalability than PoW.

17.
Opt Express ; 28(21): 30391-30409, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33115042

RESUMO

Direct-current-biased optical orthogonal frequency-division multiplexing (DCO-OFDM) is widely used in high-speed visible light communication (VLC). Due to the limited dynamic range of light-emitting diode (LED) and the unipolarity for the intensity modulation (IM), double-sided clipping is inevitably imposed on the time-domain signal in VLC OFDM systems. Consequently, it calls for proper DCO-OFDM signal shaping by selecting an appropriate bias and time-domain signal power to reduce the clipping distortion and achieve a higher transmission rate. In this paper, we deep dive into the signal shaping design problem for double-sided clipping DCO-OFDM over both flat and dispersive channels. We derive the optimal bias for flat and dispersive channels, and explain its optimality from the perspectives of effective signal-to-noise ratio (SNR) and information theory. We then analytically characterize the optimal power for flat channels and propose a useful algorithm for dispersive channels enlightened by the optimal solution to the flat case. Furthermore, we uncover an inherent relationship between the considered double-sided clipping and the downside-clipping only DCO-OFDM regarding signal shaping optimization, and develop an in-depth understanding of the impact of top clipping based on the established connection. Practical simulations are provided to validate the superiority of our proposed signal shaping over the existing shaping schemes.

18.
Nat Plants ; 6(3): 202-208, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32170285

RESUMO

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas12b is a newly emerged genome engineering system. Here, we compared Cas12b from Alicyclobacillus acidoterrestris (Aac), Alicyclobacillus acidiphilus (Aa), Bacillus thermoamylovorans (Bth) and Bacillus hisashii (Bh) for genome engineering in rice, an important crop. We found AaCas12b was more efficient than AacCas12b and BthCas12b for targeted mutagenesis, which was further demonstrated in multiplexed genome editing. We also engineered the Cas12b systems for targeted transcriptional repression and activation. Our work establishes Cas12b as the third promising CRISPR system, after Cas9 and Cas12a, for plant genome engineering.


Assuntos
Alicyclobacillus/genética , Bacillus/genética , Sistemas CRISPR-Cas , Edição de Genes , Genoma de Planta , Oryza/genética , Plantas Geneticamente Modificadas/genética
19.
Oncol Lett ; 18(6): 6331-6338, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807158

RESUMO

Despite progress in the diagnosis and treatment of acute promyelocytic leukemia (APL), its prognosis remains poor. Multiple studies have shown that long non-coding RNAs (lncRNAs) are involved in carcinogenesis and metastasis. The present study assessed the function of the lncRNA zinc finger antisense 1 (ZFAS1) in APL. In a cohort of 33 patients, ZFAS1 was significantly overexpressed compared with the level in healthy controls. To investigate the specific mechanisms of this upregulation, in vitro studies showed that silencing of ZFAS1 by small interfering RNA significantly inhibited cell proliferation in APL cells. Moreover, downregulation of ZFAS1 increased cellular apoptosis, decreased expression of B-cell lymphoma-2 and of induced myeloid leukemia cell differentiation protein Mcl-1, increased the expression of apoptosis regulator BAX and promoted the release of cytochrome c and Diablo homolog mitochondrial into the cytoplasm. In conclusion, these data indicate that ZFAS1 may serve as an oncogene in APL and may thus be a useful target for future clinical management.

20.
Nanoscale ; 11(32): 15037-15042, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31206116

RESUMO

Interfacial contacts within electrodes largely affect electronic transport and ion migration. Nanoscale electrode materials can achieve high reactivity, but their large interfacial contact areas lead to unavoidable impedance. Herein, a Ti3C2Tx MXene was used to construct a hybrid three-dimensional electrode material with a bilayer feature via a two-step vacuum filtration process. The introduced MXene flakes contributed to the electrode capacity, increased the electronic/ionic conductivity as a conductor and current collector, and enhanced the mechanical behaviour of the electrode by acting as a substrate. Such bilayer hybrid electrode design achieved promising cycling stability, and unlock an electrode architecture that can be applied to a wide range of two-dimensional materials.

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