Publications by authors named "Yiwei Qiu"

Hydrogen adsorption and desorption in single-phase catalysts often occur at a single catalytic site based on the traditional hydrogen evolution reaction (HER) pathway, which makes it difficult to break the limitation entailed by the Sabatier principle. Herein, β-Pd hydride metallene (β-PdHene) aerogels are synthesized as advanced HER catalysts. A lattice hydrogen-involved mechanism is reported to separate adsorption and desorption sites, which is thermodynamically favorable compared to the traditional reaction pathway.

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Nanozymes, possessing nanomaterial properties and catalytic activities, offer great opportunities to design sensitive analytical detection systems. However, the low interference resistance of nanozymes poses a significant limitation on the precise detection of target substances. Herein, a nanozyme-based microfluidic chip system for pH-regulated pretreatment and sensitive sensing of cysteine (Cys) is reported.

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Natural phosphatases featuring paired metal sites inspire various advanced nanozymes with phosphatase-like activity as alternatives in practical applications. Numerous efforts to create point defects show limited metal site pairs, further resulting in insufficient activity. However, it remains a grand challenge to accurately engineer abundant metal site pairs in nanozymes.

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FeNC catalysts are considered one of the most promising alternatives to platinum group metals for the oxygen reduction reaction (ORR). Despite the extensive research on improving ORR activity, the undesirable durability of FeNC is still a critical issue for its practical application. Herein, inspired by the antioxidant mechanism of natural enzymes, CeO nanozymes featuring catalase-like and superoxide dismutase-like activities were coupled with FeNC to mitigate the attack of reactive oxygen species (ROS) for improving durability.

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The rational design of efficient catalysts for uric acid (UA) electrooxidation, as well as the establishment of structure-activity relationships, remains a critical bottleneck in the field of electrochemical sensing. To address these challenges, herein, a hybrid catalyst that integrates carbon-supported Pt nanoparticles and nitrogen-coordinated Mn single atoms (Pt/MnNC) is developed. The metal-metal interaction during annealing affords the construction of metallic-bonded Pt-Mn pairs between Pt and Mn single atoms, facilitating the electron transfer from Pt to the support and thereby optimizing the electronic structure of catalysts.

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Mask-free multi-photon lithography enables the fabrication of arbitrary nanostructures low cost and more accessible than conventional lithography. A major challenge for multi-photon lithography is to achieve ultra-high precision and desirable lateral resolution due to the inevitable optical diffraction barrier and proximity effect. Here, we show a strategy, light and matter co-confined multi-photon lithography, to overcome the issues via combining photo-inhibition and chemical quenchers.

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Article Synopsis
  • Engineering isolated metal sites in nanozymes can create highly efficient catalysts.
  • Existing designs often overlook the role of supporting cofactors, which can limit their effectiveness in electron transfer.
  • This study presents a novel UiO-67 nanozyme with strategically combined iron sites and nanocofactors, achieving over four times better catalytic performance for detecting chlorpyrifos, paving the way for advanced nanozyme development.
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Photoinhibition (PI) mechanisms have been introduced in nanofabrication which allows breaking the diffraction limit by large factors. Donut-shaped laser is usually selected as a depletion beam to reduce linewidth, but the parasitic process has made the results of the experiment less than expected. As a result, the linewidth is difficult to achieve below 50 nm with 780 nm femtosecond and 532 nm continuous-wave lasers.

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For decades, photoinhibited two-photon lithography (PI-TPL) has been continually developed and applied into versatile nanofabrication. However, ultrahigh precision fabrication on wafer by PI-TPL remains challenging, due to the lack of a refractive index () matched photoresist (Rim-P) with effective photoinhibition capacity for dip-in mode. In this paper, various Rim-P are developed and then screened for their applications in PI-TPL.

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The problem of gene recognition based on the ratio of power spectrum, SNR, and Gabor transform and its implementation of the calculation were discussed. The optimal threshold could guarantee to identify the DNA sequences with the signal-to-noise ratio. It summarized three kinds of traditional ways to determine the threshold, and advanced the optimum entitled method showing the disparate degrees of highlight and the discrimination rate method of the exons or introns as far as possible to improve the rate of their accuracy.

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Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in patients with injuries and inflammation of tendon and ligament, and as post-surgical analgesics. The aim of this study is to investigate the effect of indomethacin, a classic NSAID and its combinational effect with an anabolic agent of skeletal tissue, lactoferrin, on the proliferation and collagen formation of human tenocytes in vitro. A factorial experimental design was employed to study the dose-dependent effect of the combination of indomethacin and lactoferrin.

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In order to examine the differentiation potential of the tenocytes expanded in our defined culture medium (reported previously) and the effect of sequential combination of the two culture conditions on human tenocytes, a two-dimensional and three-dimensional experimental approach was used. Human tenocytes were sequentially exposed to 1% fetal bovine serum (FBS) + 50 ng/ml platelet-derived growth factor-BB (PDGFBB ) + 50 ng/ml basic fibroblast growth factor (bFGF) for the first 14 days (expansion phase) followed by a further 14-day culture in the presence of 10 ng/ml transforming growth factor β-3 plus 50 ng/ml insulin-like growth factor 1, but in the absence of serum (differentiation phase). The results showed that by sequential treatment of human tenocytes maintaining a long-term two-dimensional tenocyte culture in vitro for up to 28 days was possible.

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Background: Hyponatremia is a common but often mistreated clinical situation in the ICU. This often requires the physician to identify the underlying problem, adrenal insufficiency. However, by the textbook, the current treatment always involves sodium chloride supplementation to hyponatremic patients, either intravenous or oral intake.

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Objective: To optimize the culture media by adding the growth factors required to maintain tenocytes survival and promote their differentiation without fetal bovine serum (FBS) supplementation, in order for the approach to be used for any future tendon tissue engineering.

Methods: The human tenocytes were cultured in α-MEM media by adding FBS at various concentrations and supplementing both insulin-like growth factor 1 (IGF-1) and transforming growth factor β-3 (TGFβ-3). A number of growth factors were selected that could support tenocytes expansion at reduced differentiated state with the minimum FBS.

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The aim of this study was to efficiently expand less differentiated tenocytes with minimum use of fetal bovine serum (FBS) for tenocyte-based tendon tissue engineering. To achieve this goal, human tenocytes were cultured in different concentrations of FBS and combinations of growth factors PDGF(BB), IGF-1 and bFGF. A number of growth factors were selected that could support tenocyte expansion at reduced differentiated state with minimum FBS usage.

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We have established that human tenocytes can differentiate in the absence of exogenous fetal bovine serum (FBS) but in the presence of insulin-like growth factor-1 (IGF-1) and transforming growth factor-β3 (TGF-β3). The extent of tenocyte differentiation was assessed by examining cell survival, collagen synthesis, cell morphology and expression of tenocyte differentiation markers such as scleraxis (Scx), tenomodulin (Tnmd), collagen type I (Col-I) and decorin (Dcn). Our results indicate that 50 ng/ml IGF-1 and 10 ng/ml TGF-β3 (in the absence of FBS) were capable of maintaining in vitro human tenocyte survival in 14-day cultures.

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Platelet rich plasma (PRP) is the autologous plasma fraction with a platelet-rich cellular component which is enriched with a number of growth factors. Due to its availability and low cost, PRP has become an increasingly popular clinical tool as an alternative source of growth factors for various applications, for example, tendon regeneration but with limited success in clinical trials. The main objective of the current study was to determine whether activated PRP [i.

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Tendon disorders are common clinical conditions. Tendon tissue engineering provides a new approach for tendon repair by integrating engineered substitutes with their native counterparts. Silk is considered to be a promising candidate for tendon engineering because of its biological and mechanical properties.

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