Semiconductor quantum dots (QDs) are highly attractive nanomaterials with wide biomedical applications owing to their unique photophysical properties. However, the adaptation of the nonenzymatic QD ...nanosensor assembly to sense low-abundance targets remains a great challenge. Herein, taking advantage of the dynamic DNA nanotechnology and single-molecule fluorescence detection, we demonstrate the catalytic self-assembly of a QD-based microRNA nanosensor directed by toehold-mediated strand displacement cascade for the simple and sensitive detection of microRNA at femtomolar concentration without the requirement of any enzymes. Moreover, this QD nanosensor is capable of detecting circulating microRNA in clinical serum samples and even imaging microRNA in living cells. This work may extend the use of an enzyme-free QD nanosensor assembly for low-abundance biomarker detection and offer a novel platform for fundamental biomedical research and clinical applications.
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IJS, KILJ, NUK, PNG, UL, UM
Symmetry‐breaking synthesis of colloidal nanocrystals with desired structures and properties has aroused widespread interest in various fields, but the lack of robust synthetic protocols and the ...complex growth kinetics limit their practical applications. Herein, a general strategy is developed to synthesize the Au–Cu Janus nanocrystals (JNCs) through the site‐selective growth of Cu nanodomains on Au nanocrystals, which is directed by the substantial lattice mismatch between them, with the assistance of judicious manipulation of the growth kinetics. This strategy can work on Au nanocrystals with different architectures for the achievement of diverse asymmetric Au–Cu hybrid nanostructures. Of particular note, the obtained Au nanobipyramids (Au NBPs)‐based JNCs facilitate the conversion of CO2 to C2 hydrocarbon production during electrocatalysis, with the Faradaic efficiency and maximum partial current density being 4.1‐fold and 6.4‐fold higher than those of their monometallic Cu counterparts, respectively. The excellent electrocatalytic performances benefit from the special design of the Au–Cu Janus architectures and their tandem catalysis mechanism as well as the high‐index facets on Au nanocrystals. This research provides a new approach to synthesize various hybrid Janus nanostructures, facilitating the study of structure‐function relationship in the catalytic process and the rational design of efficient heterogeneous electrocatalysts.
A general strategy is developed to grow Cu nanodomains site selectively on Au nanocrystals. This strategy works on Au nanocrystals from 0D, 1D, to 2D for the achievement of diverse asymmetric Au−Cu hybrid nanostructures. This spatial‐separation design with high‐index facets on Au nanocrystals facilitates the conversion of CO2 to C2 product through the tandem catalysis mechanism.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abstract
A safety instrumented system (SIS) is extensively used to prevent or reduce risk. The Probability of Failure to perform its intended functions on Demand (PFD) of a practical SIS may vary ...within multiple safety integrity levels (SIL) due to uncertainties relevant to input parameters. An SIS will be considered to be unsafe when its PFD is greater than a prescribed value, and unsafety probability (UP) is employed to measure the unsafety degree of the investigated SIS in this work. Redundancy architecture is commonly employed to improve the reliability of an SIS. This paper investigates the effects of multiple uncertain input parameters on the UP of an SIS with the k‐out‐of‐n redundancy arrangement. We derive the detailed formulations of the sensitivity for such effects and we also discuss the physical meaning of the proposed sensitivity. An example is employed to demonstrate the proposed sensitivity and the results show that the estimated sensitivity values will be kept to be unchanged with respect to the redundancy when the redundancy is high, whereas the results will vary with the redundancy when the redundancy is low. Meanwhile, we provide a comparison of the results for the truncated uncertain parameters and the non‐truncated uncertain parameters. The results for truncated uncertain parameters and non‐truncated uncertain parameters will approach the same values as the truncated region of the uncertain parameter reduces to zero. The results show that we can approximate the sensitivities of the truncated parameters by the ones of the non‐truncated parameters with less computation time when the truncated region is less than 10
−3
.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Highly fluorescent graphitic carbon nitride quantum dots (g-CNQDs) with a quantum yield of 42% are synthesized by a low-temperature solid-phase method with urea and sodium citrate as the precursors. ...Notably, the tunable emission of g-CNQDs can be achieved by simply adjusting the molar ratio of the two reactants.
Objective: The health action process approach (HAPA) is a social-cognitive model specifying motivational and volitional determinants of health behavior. A meta-analysis of studies applying the HAPA ...in health behavior contexts was conducted to estimate the size and variability of correlations among model constructs, test model predictions, and test effects of past behavior and moderators (behavior type, sample type, measurement lag, study quality) on model relations. Method: A literature search identified 95 studies meeting inclusion criteria with 108 independent samples. Averaged corrected correlations among HAPA constructs and multivariate tests of model predictions were computed using conventional meta-analysis and meta-analytic structural equation modeling, with separate models estimated in each moderator group. Results: Action and maintenance self-efficacy and outcome expectancies had small-to-medium sized effects on health behavior, with effects of outcome expectancies and action self-efficacy mediated by intentions, and action and coping planning. Effects of risk perceptions and recovery self-efficacy were small by comparison. Past behavior attenuated the intention-behavior relationship. Few variations in model effects were observed across moderator groups. Effects of action self-efficacy on intentions and behavior were larger in studies on physical activity compared with studies on dietary behaviors, whereas effects of volitional self-efficacy on behavior were larger in studies on dietary behaviors. Conclusions: Findings highlight the importance of self-efficacy in predicting health behavior in motivational and volitional action phases. The analysis is expected to catalyze future research including experimental studies targeting change in individual HAPA constructs, and longitudinal research to examine change and reciprocal effects among constructs in the model.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ, UPUK
CRISPR/Cas‐Based MicroRNA Biosensors Zhang, Qian; Zhang, Xinyi; Zou, Xiaoran ...
Chemistry : a European journal,
March 16, 2023, Volume:
29, Issue:
16
Journal Article
Peer reviewed
As important post‐transcriptional regulators, microRNAs (miRNAs) play irreplaceable roles in diverse cellular functions. Dysregulated miRNA expression is implicated in various diseases including ...cancers, and thus miRNAs have become the valuable biomarkers for disease monitoring. Recently, clustered regularly interspaced short palindromic repeats/CRISPR‐associated (CRISPR/Cas) system has shown great promise for the development of next‐generation biosensors because of its precise localization capability, good fidelity, and high cleavage activity. Herein, we review recent advance in development of CRISPR/Cas‐based biosensors for miRNA detection. We summarize the principles, features, and performance of these miRNA biosensors, and further highlight the remaining challenges and future directions.
The construction of efficient biosensors for miRNA assay is essential for disease diagnosis, therapy, and prognosis. CRISPR/Cas system possesses high fidelity, precise localization capability, and efficient cleavage activity, making it attractive in biosensing applications. In this review, the recent advances in the development of CRISPR/Cas‐based biosensors for miRNAs assay are discussed.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
(R,S)-ketamine elicits rapid-acting and sustained antidepressant actions in treatment-resistant patients with depression. (R)-ketamine produces longer-lasting antidepressant effects than (S)-ketamine ...in rodents; however, the precise molecular mechanisms underlying antidepressant actions of (R)-ketamine remain unknown. Using isobaric Tag for Relative and Absolute Quantification, we identified nuclear receptor-binding protein 1 (NRBP1) that could contribute to different antidepressant-like effects of the two enantiomers in chronic social defeat stress (CSDS) model. NRBP1 was localized in the microglia and neuron, not astrocyte, of mouse medial prefrontal cortex (mPFC). (R)-ketamine increased the expression of NRBP1, brain-derived neurotrophic factor (BDNF), and phosphorylated cAMP response element binding protein (p-CREB)/CREB ratio in primary microglia cultures thorough the extracellular signal-regulated kinase (ERK) activation. Furthermore, (R)-ketamine could activate BDNF transcription through activation of CREB as well as MeCP2 (methyl-CpG binding protein 2) suppression in microglia. Single intracerebroventricular (i.c.v.) injection of CREB-DNA/RNA heteroduplex oligonucleotides (CREB-HDO) or BDNF exon IV-HDO blocked the antidepressant-like effects of (R)-ketamine in CSDS susceptible mice. Moreover, microglial depletion by colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX3397 blocked the antidepressant-like effects of (R)-ketamine in CSDS susceptible mice. In addition, inhibition of microglia by single i.c.v. injection of mannosylated clodronate liposomes (MCLs) significantly blocked the antidepressant-like effects of (R)-ketamine in CSDS susceptible mice. Finally, single i.c.v. injection of CREB-HDO, BDNF exon IV-HDO or MCLs blocked the beneficial effects of (R)-ketamine on the reduced dendritic spine density in the mPFC of CSDS susceptible mice. These data suggest a novel ERK-NRBP1-CREB-BDNF pathways in microglia underlying antidepressant-like effects of (R)-ketamine.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The h-index has already been used by major citation databases to evaluate the academic performance of individual scientists. Although effective and simple, the h-index suffers from some drawbacks ...that limit its use in accurately and fairly comparing the scientific output of different researchers. These drawbacks include information loss and low resolution: the former refers to the fact that in addition to h(2) citations for papers in the h-core, excess citations are completely ignored, whereas the latter means that it is common for a group of researchers to have an identical h-index.
To solve these problems, I here propose the e-index, where e(2) represents the ignored excess citations, in addition to the h(2) citations for h-core papers. Citation information can be completely depicted by using the h-index together with the e-index, which are independent of each other. Some other h-type indices, such as a and R, are h-dependent, have information redundancy with h, and therefore, when used together with h, mask the real differences in excess citations of different researchers.
Although simple, the e-index is a necessary h-index complement, especially for evaluating highly cited scientists or for precisely comparing the scientific output of a group of scientists having an identical h-index.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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