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Metal–organic frameworks (MOFs), as porous materials, have great potential for exploring high-performance electrochemiluminescence (ECL) probes. However, the constrained applicability of MOFs in the realm of ECL biosensing is primarily attributed to their inadequate water stability, which consequently impairs the overall ECL efficiency. Herein, we developed a competitive ECL biosensor based on a novel tightest structural ruthenium-based organic framework emitter combining the proximity hybridization-induced catalytic hairpin assembly (CHA) strategy and the quenching effect between the Ru-MOF and ferrocene for detecting paraquat (PQ). Through a simple hydrothermal synthesis strategy, ruthenium and 2,2ʹ-bipyrimidine (bpm) are head-to-head self-assembled to obtain a novel tightest structural Ru-MOF. Due to the metal–ligand charge-transfer (MLCT) effect between ruthenium and the bpm ligand and the connectivity between the internal chromophore units, the Ru-MOF exhibits strong ECL emissions. Meanwhile, the coordination-driven Ru-MOF utilizes strong metal–organic coordination bonds as building blocks, which effectively solves the problem of serious leakage of chromophores caused by water solubility. The sensitive analysis of PQ is realized in the range of 1 pg/mL to 1 ng/mL with a detection limit of 0.352 pg/mL. The tightest structural Ru-MOF driven by the coordination of ruthenium and bridging ligands (2,2ʹ-bipyrimidine, bpm) provides new horizons for exploring high-performance MOF-based ECL probes for quantitative analysis of biomarkers. [ABSTRACT FROM AUTHOR]

Exosomes play a crucial role in regulating crosstalk between tumor and tumor stem-like cells through their cargo molecules. Circular RNAs (circRNAs) have recently been demonstrated to be critical factors in tumorigenesis. This study focuses on the molecular mechanism by which circRNAs from glioma stem-like cell (GSLC) exosomes regulate glioblastoma (GBM) tumorigenicity. In this study, we validated that GSLC exosomes accelerated the malignant phenotype of GBM. Subsequently, we found that circZNF800 was highly expressed in GSLC exosomes and was negatively associated with GBM patients. CircZNF800 promoted GBM cell proliferation and migration and inhibited GBM cell apoptosis in vitro. Silencing circZNF800 could improve the GBM xenograft model survival rate. Mechanistic studies revealed that circZNF800 activated the PIEZO1/Akt signaling pathway by sponging miR-139-5p. CircZNF800 derived from GSLC exosomes promoted GBM cell tumorigenicity and predicted poor prognosis in GBM patients. CircZNF800 has the potential to serve as a promising target for further therapeutic exploration. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is a highly vascularized tumor, one of the most common and lethal cancer-related tumor deaths worldwide, with cell proliferation playing a key role. In this study our western blot results and data from TAGC demonstrate a strong association between Sorcin (SRI) overexpression and poor outcomes in HCC. Moreover, SRI overexpression was remarkably effective in promoting proliferation in vitro and increasing tumor growth in vivo, which were attenuated by knocking down SRI. Mechanistically, SRI regulated vascular endothelial growth factor A (VEGFA) and vascular endothelial growth factor B (VEGFB) through PI3K/Akt/FOXO1 signal pathway. Overall, our study indicates that SRI stimulates HCC growth by controlling VEGFA/B, which presents a fresh insight into the pathogenesis of hepatocarcinogenesis and a new therapeutic target for HCC. [ABSTRACT FROM AUTHOR]

For a given matrix G ∈ R k × n , let the set Ω G = Null (G) , and let A S Ω G (R n × n) = { A ∈ R n × n | (A x , y) = (x , - A y) , ∀ x , y ∈ Ω G } , that is, AS Ω G (R n × n) is the set of all anti-symmetric matrices on Ω G . In this paper, we first consider the following problem (Problem 1): Given A ∈ R m × n , B ∈ R m × m , find X ∈ AS Ω G (R n × n) such that A X A ⊤ = B . Then, we consider the associated optimal approximation problem: Given X ~ ∈ R n × n , find X ^ ∈ S Ω G (A , B) such that X ^ = arg min X ∈ S Ω G (A , B) ‖ X - X ~ ‖ , where ‖ · ‖ is the Frobenius norm and S Ω G (A , B) is the solution set of Problem 1. By using the generalized singular value decomposition of a matrix pair, we deduce the solvability condition and the representation of the general solution of Problem 1. Moreover, we obtain the unique approximation solution X ^ of the optimal approximation problem. Finally, a numerical example is presented to show the correctness of our result. [ABSTRACT FROM AUTHOR]

The chromium (Cr) evaporation from balance-of-plant (BoP) component alloys in high-temperature environments can severely deteriorate the electrochemical performance of solid oxide cells (SOCs) in fuel (SOFC) and electrolysis (SOEC) modes. However, accurate assessment of Cr evaporation is challenging due to potential interferences from the experimental conditions and test apparatus. In this study, we investigate four distinct methods for assessing the Cr evaporation rates of candidate alumina-forming austenitic and chromia-forming austenitic BoP alloys under relevant simulated SOC operating conditions of 800–900 °C in air with 10% H2O. A method using a sodium carbonate coated thin alumina tube is identified, which effectively mitigates the interference caused by (1) the deposition of silicon deposits originating from quartz furnace tubes, (2) detrimental effects of sodium species on the oxidation process of alloys from the sodium carbonate used to enhance Cr oxy hydroxide species capture, or (3) chemical interaction between Cr gaseous species and the alumina furnace tube. This optimal method provides improved assessment of Cr evaporation, enabling further efforts to build correlation between Cr species quantities to the degradation rates of SOCs. [ABSTRACT FROM AUTHOR]

Purpose: Trastuzumab deruxtecan (T-DXd) expressed substantial improvement in the progression-free survival and overall survival contrasted with trastuzumab emtansine (T-DM1) in patients with HER2-positive metastatic breast cancer (mBC), becoming the second-line standard of care, promisingly. We aim to estimate the cost–utility of T-DXd versus T-DM1 in HER2-positive mBC from the Chinese healthcare perspective. Methods: A partitioned survival model was applied to examine the cost–utility of T-DXd versus T-DM1. Clinical patients and outcome data were sourced from the DESTINY-Breast 03 trial. Costs and utilities were sourced in Chinese setting. Total costs, quality-adjusted life months (QALMs), and an incremental cost–utility ratios (ICUR) were calculated for cost–utility analysis. The willingness-to-pay threshold was set at $3188/QALM. Univariate, scenario, and probabilistic sensitivity analyses were performed. Results: T-DXd group gained ∆QALM of 7.09 months and ∆Cost of $304,503 compared with T-DM1 therapy, which caused an ICUR of $42,936/QALM. The results of sensitivity analyses confirmed the base-case findings. Furthermore, T-DXd must reduce the price to enter the Chinese mainland market. At least when the cycle cost of T-DXd is reduced to $2975, T-DXd has an 83.3% chance of becoming a better choice. Conclusions: T-DXd appears to be not cost effective compared with T-DM1 for HER2-positive mBC patients previously treated with trastuzumab and a taxane. [ABSTRACT FROM AUTHOR]

Let S R Ω n × n be the set of all n × n symmetric matrices on subspace Ω , where Ω = { z ∈ R n | G z = 0 , G ∈ R k × n }. The necessary and sufficient conditions for the matrix equations A X = B and X C = D to have a common solution in S R Ω n × n and also an expression for the general common solution are obtained. Further, the associated optimal approximate problem to a given matrix X ~ ∈ R n × n is discussed and the optimal approximate solution is elucidated. Finally, a numerical experiment is presented to validate the accuracy of our result. [ABSTRACT FROM AUTHOR]

Let Ω = { z ∈ R n | G z = 0 , G ∈ R k × n } and S R Ω n × n = { A ∈ R n × n | (A x , y) = (x , A y) , ∀ x , y ∈ Ω } . In this paper, we first consider the following problem (Problem 1): Given A ∈ R m × n , B ∈ R n × q and D ∈ R m × q , find X ∈ S R Ω n × n such that A X B = D . Further, we consider an associated optimal approximation problem: Given X ~ ∈ R n × n , find X ^ ∈ S E such that ‖ X ^ - X ~ ‖ = min X ∈ S E ‖ X - X ~ ‖ , where S E is the solution set of Problem 1. The solvability conditions and the representation of the general solution of Problem 1 are derived by using the generalized inverses, and then, the unique approximation solution X ^ of the optimal approximation problem are deduced by applying the Kronecker product of matrices. Finally, two numerical examples are presented to show the correctness of our results. [ABSTRACT FROM AUTHOR]

Key message: The powdery mildew resistance gene Pm58 was traced to a 141.3-kb interval with the co-segregating marker Xkasp68500 in wheat breeding. Pm58 is a powdery mildew resistance gene identified in Aegilops tauschii accession TA1662 and effective in a common wheat background. To finely map Pm58, an F2 population of 676 plants derived from the cross T093 × TA1662 was used for recombinant screening. We obtained 13 recombinants that occurred between the flanking markers Xhnu670 and Xhnu186. Genotyping and phenotyping these recombinant F2:3 families delimited Pm58 to a 0.22-cM interval (Xsts20220–Xkasp61553) on chromosome arm 2DS. The region carrying the Pm58 locus was approximately 141.3-kb, which contained eight annotated genes according to the reference genome sequence of Ae. tauschii AL8/78. Haplotype analysis of 178 Ae. tauschii accessions using the candidate gene-specific markers identified a disease resistance gene AET2Gv20068500 as a candidate for Pm58. Comparative mapping of the Pm58-containing interval revealed two presence/absence variations (PAVs) between AL8/78 and common wheat Chinese Spring. PAV-1 resides in the 3′-end of AET2Gv20068500. The majority of 158 common wheat cultivars (84.8%) displayed the absence of a 14.1-kb fragment in the PAV-1 region, which was confirmed by aligning the targeted genome sequences of the other sequenced Ae. tauschii accessions and common wheat cultivars. A co-segregating marker Xkasp68500 developed from AET2Gv20068500 can distinguish TA1662 from all randomly selected common wheat cultivars and will be instrumental for tracking Pm58 in breeding programs. [ABSTRACT FROM AUTHOR]

At present, the mortgage loan of farmland contractual management right is in the pilot and exploration stage. In this overall environment, how to formulate an appropriate pricing model according to the particularity of farmland property right and the actual situation is the theoretical support to be solved. On the basis of theoretical analysis, model construction and analysis of existing problems, this paper establishes a binary tree pricing method of farmland management right mortgage based on machine learning and complex network algorithm. This paper analyzes the basic theory of rural land management right mortgage pricing and constructs the pricing model. Based on the Markov decision process model of dynamic pricing problem, this paper proposes the solution algorithm and proposes the dynamic pricing solution for this paper from two aspects of value function and strategy gradient reinforcement learning algorithm. This paper analyzes the basic principle of A3C algorithm and expounds the algorithm design and neural network architecture for the specific dynamic pricing problem in this paper. The dynamic pricing method of rural land mortgage based on deep reinforcement learning designed in this paper can well predict the real price of rural land management right mortgage pricing and effectively optimize the mortgage loan environment of rural contracted land management right, which is the innovation of financial system in the current new rural construction. [ABSTRACT FROM AUTHOR]

Underwater laser drilling of alumina ceramics is an effective means to improve the quality of holes in the material. In the process of underwater laser drilling, not only water plays a great role in improving the quality of the hole, but also bubbles (generated by ceramic melting explosions in water) play an important effect in reducing the recast layer of the hole wall. In this paper, the influence mechanism of water and bubbles on the surface quality of the hole of laser drilling in water was studied. Two sets of experiments were performed for the laser drilling of alumina ceramics in air and in water, respectively. The results showed that water and bubbles effectively reduced the thickness of the recast layer and the amount of spatter. Moreover, by comparing the width of cracks on the hole wall of the alumina ceramic drilled by the laser in air and in water, it was found that water significantly reduced the thermal effect of the laser. The collapse and rupture of the bubbles produced shock and vibration, causing the recast layer on the inner wall of the hole to fall off. However, the cooling time of the recast layer was reduced due to the cooling effect of water. If the bubbles cannot be broken in time, it will cause the formation of a blowhole on the hole wall. When the input current of the laser machine was 160 A, both water and bubbles were helpful to improve the quality of laser drilling alumina ceramics. The research in this article supplements the mechanism of underwater laser drilling. And it has important reference value in engineering application. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "A mussel-inspired film for adhesion to wet buccal tissue and efficient buccal drug delivery" published in Nature Communications. The notice states that errors were found in Figures 6c, 7b, and in Supplementary Figs. 5d, 8d, 8f due to the similarity of different group names. The errors have been corrected in both the PDF and HTML versions of the article. The notice also provides a link to the corrected supplementary information. The authors of the article are Shanshan Hu, Xibo Pei, Lunliang Duan, Zhou Zhu, Yanhua Liu, Junyu Chen, Tao Chen, Ping Ji, Qianbing Wan, and Jian Wang. [Extracted from the article]

Both temperature and nutrient nitrogen are rising in worldwide aquatic ecosystems. To explore their interactive impacts on algal physiology, we measured the growth, cell components, photosynthesis, and dark respiration of a farmed green alga, Caulerpa lentillifera, under a matrix of temperatures (low, 22 °C; high, 27 °C) and nitrogen concentrations (low, 47 μmol L−1; medium, 188 μmol L−1; high, 750 μmol L−1). The relative growth rate (RGR) was less than 1.0% day−1 at low temperature, which was ~ eightfold higher at high temperature, with no significant effect of nitrogen. Pigment contents of chlorophyll a (Chl a) and carotenoids (Car) and soluble protein content increased with increasing nitrogen levels. High temperature reduced Chl a content under lower nitrogen and enhanced Car contents under higher nitrogen, but had a limited effect on proteins. Photosynthetic parameters, i.e., light-utilized efficiency (α) and maximum photosynthetic rate (Pmax), and dark respiration rate (Rd) increased with increasing nitrogen levels at low temperature. High temperature enhanced the α, Pmax, and Rd under low nitrogen, but reduced them under high nitrogen. Moreover, high temperature lowered both superoxide dismutase (SOD) and catalase (CAT) contents, indicating the beneficial effects on metabolism of C. lentillifera and thus the growth. In addition, our results indicate that the temperature-caused effects on photosynthesis and respiration of C. lentillifera are reversed by increased nitrogen levels. [ABSTRACT FROM AUTHOR]

Administration of drugs via the buccal route has attracted much attention in recent years. However, developing systems with satisfactory adhesion under wet conditions and adequate drug bioavailability still remains a challenge. Here, we propose a mussel-inspired mucoadhesive film. Ex vivo models show that this film can achieve strong adhesion to wet buccal tissues (up to 38.72 ± 10.94 kPa). We also demonstrate that the adhesion mechanism of this film relies on both physical association and covalent bonding between the film and mucus. Additionally, the film with incorporated polydopamine nanoparticles shows superior advantages for transport across the mucosal barrier, with improved drug bioavailability (~3.5-fold greater than observed with oral delivery) and therapeutic efficacy in oral mucositis models (~6.0-fold improvement in wound closure at day 5 compared with that observed with no treatment). We anticipate that this platform might aid the development of tissue adhesives and inspire the design of nanoparticle-based buccal delivery systems. Minimally invasive drug delivery is of wide interest and oral tissue is an attractive target for this. Here, the authors report on the creation of mussel-inspired films for retention on the wet oral tissue for the delivery of drugs by diffusion and transport though the mucosal tissue. [ABSTRACT FROM AUTHOR]

Mammalian mitochondria have small genomes encoding very limited numbers of proteins. Over one thousand proteins and noncoding RNAs encoded by the nuclear genome must be imported from the cytosol into the mitochondria. Here, we report the identification of hundreds of circular RNAs (mecciRNAs) encoded by the mitochondrial genome. We provide both in vitro and in vivo evidence to show that mecciRNAs facilitate the mitochondrial entry of nuclear-encoded proteins by serving as molecular chaperones in the folding of imported proteins. Known components involved in mitochondrial protein and RNA importation, such as TOM40 and PNPASE, interact with mecciRNAs and regulate protein entry. The expression of mecciRNAs is regulated, and these transcripts are critical for the adaption of mitochondria to physiological conditions and diseases such as stresses and cancers by modulating mitochondrial protein importation. mecciRNAs and their associated physiological roles add categories and functions to the known eukaryotic circular RNAs and shed novel light on the communication between mitochondria and the nucleus. [ABSTRACT FROM AUTHOR]

In recent years, various particulate materials have played important roles in medical applications. However, nano- and micron-sized particles of the same material could exhibit distinct properties due to different particle sizes. This finding provided a simple and effective way to improve the biological applications of particulate materials. Therefore, as a highly promising member, the effect of the particle size change of the magnesium metal organic framework-74 (Mg-MOF74) was well worth evaluating. Here we firstly assessed the in vitro and in vivo toxicity of micron/nanoscale Mg-MOF74 (m-Mg-MOF74/n-Mg-MOF74) in detail. Our in vitro study revealed that compared to micron-sized subjects, n-Mg-MOF74 provided a wider range of safe concentrations. Furthermore, both micron/nanoscale Mg-MOF74 showed good biocompatibility and allowed all the rats under the treatment to survive through the expected experimental periods, with n-Mg-MOF74 still showing lower cardiotoxicity. These advantages of nanoscale Mg-MOF74 might benefit from its sustainable and balanced release of Mg2+ both inside and outside the cells. Based on the biosafety evaluation, advanced bio-functional assessments of m/n-Mg-MOF74 including early osteogenesis and angiogenesis were also performed. Similarly, the suitable dose groups of n-Mg-MOF74 achieved optimal early osteogenic promotion and angiogenic stimulation effects. Overall, our combined data delineated the toxicity and biological behaviors of Mg-MOF74 of different scales, and suggested nanoscale Mg-MOF74 as a better choice for future applications. This result revealed that particle size reduction might be a viable strategy to improve and expand medical applications of MOFs or other particulate materials. [ABSTRACT FROM AUTHOR]

Shear fractures that close under compressive stress regime were described by previous workers. Here, we show the existence of hinge-parallel shear-opening mode fractures at a certain depth within an anticline structure, through core observations, Formation Micro Imager (FMI) log interpretations and production data. Studied reservoir is a tight sandstone body of Cretaceous age, which is emplaced in KS2 Anticline, with depth ranging between 6000 and 8100 m. We explore the mechanism of hinge-parallel shear fractures by stereographic technique and backtilting, as well as show field evidences for opening displacements. These shear fractures mainly consist of vertical tension set, moderate-dipping shear set, steeply dipping shear set and sub-horizontal shear set. Crosscutting relationships and surface textures suggest that although the moderate-dipping shear set is older and maybe sealed by cements, it may have been opened by local stress due to outer-arc extension through folding. Calcite bridges with rhombohedral structures may support fracture walls helping them to remain open in case of compressive stress. Our work documents shear fracture openings in the anticline at depth, and fluid flow in subsurface reservoirs. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus is a risk factor for congenital heart defects. Our previous results indicated that a decrease in myocardial cells and an increase in apoptotic cells leads to heart defects under hyperglycemia, but much work remains to elucidate this important mechanism of myocardial cell apoptosis induced by high glucose (HG). In this study, we found that a decrease in GSK3β phosphorylation on Ser9 occurred concomitantly with HG-induced cardiomyocyte apoptosis and in the heart tissues of the offspring of diabetic rats in vitro and in vivo. Decreases in GSK3β (Ser9) phosphorylation in response to HG were remarkably restored after treatment with SC79, an activator of the Akt signaling pathway. SB216763, an effective inhibitor of the GSK3β signaling pathway, suppressed HG-induced apoptosis in cardiomyocytes. Further studies showed a decrease in the expression of the anti-apoptotic protein MCL-1 was associated with GSK3β-mediated apoptosis. MCL-1 overexpression partly inhibits HG-induced apoptosis in cardiomyocytes. Herein, this study revealed the roles of GSK3β and MCL-1 in modulating HG-induced cardiomyocyte apoptosis and maternal diabetes-induced abnormalities. [ABSTRACT FROM AUTHOR]

Previously, ginsenoside metabolite compound K (C-K) was able to reduce B cell proliferation and serum anti-type II collagen (anti-CII) antibody to normal levels in mice with collagen-induced arthritis (CIA); however, the mechanism by which C-K restores B cell balance is unclear. In the present work, C-K treatment not only alleviated the polyarthritis index, swollen joint count, pathological scores of spleen and joints, spleen index, B cell proliferation and the level of serum antibodies (IgG1, IgG2a and anti-collagen II), but C-K treatment also restored B cell subsets including regulatory B cells, plasma cells, memory B cells, mature B cells, and follicular B cells in CIA mice. Interestingly, C-K did not change the expression level of immunoglobulin D-type B-cell receptor (IgD-BCR) but promoted IgD-BCR endocytosis. C-K treatment enhanced β-arrestin1 expression, facilitating the colocalization between IgD and β-arrestin1, as well as colocalization between IgD and adaptor protein 2 (AP2). Inhibition of the β-arrestin1-AP2 interaction with barbadin significantly reduced the ability of C-K to attenuate IgD-BCR plasma membrane localization. These results taken together depict that C-K ameliorates CIA in part by inhibiting B cell activation through the triggering of IgD-BCR internalization in a β-arrestin1-AP2 dependent manner. [ABSTRACT FROM AUTHOR]

Sludge treatment beds (STBs) have been used widely in many countries due to low energy consumption, low operating and maintenance costs, and better environmental compatibility. Penetration, evaporation, and transpiration are the main processes for sludge dewatering in STBs. However, the leachate quality from STBs usually cannot meet discharge limits. Moreover, such leachate has very low COD/N ratio, which makes it difficult to treat. In the present study, two subsurface flow (SSF) constructed wetlands (CWs) were investigated for the treatment of leachate from STBs under three different hydraulic retention time (HRT) (3 days, 4 days, 6 days), aiming for evaluating the effects of plants and HRT on treatment performance, as well as the potential of SSF CWs to treat sludge leachate with low COD/N ration. The results showed that plants play an important role in leachate treatment. The best treatment performance was achieved with HRT of 4 days. In this condition, the mean removal efficiencies of COD (chemical oxygen demand), NH4+-N, TN (total nitrogen), and TP (total phosphorus) in the planted and the unplanted CWs were 61.6% (unplanted − 3.7%), 76.6% (unplanted 43.5%), 70% (unplanted 41%), and 65.6% (unplanted 6%), respectively. Heavy metal concentrations were below the Chinese integrated wastewater discharge standard during the experimental period in the planted CW, and the removal efficiencies in the planted CW system were higher than in the unplanted CW system. In all, planted SSF CWs can be an effective approach in removing leachate from sludge treatment beds. Furthermore, considering to temperature and seasonal variation, the leachate from STBs needs to be further studied in pilot- and full-scale condition. [ABSTRACT FROM AUTHOR]

The drilling of ceramic pores with a YAG laser beam raises some problems such as a big taper angle, accumulation of slag, and a recast layer. Three sets of experiments are conducted to verify that repeat drilling in static water can effectively reduce these problems by drilling once in air, repeat drilling in air, and repeat drilling in water. A mist-blowing method is adopted to blow over the water mist caused by laser heating. The effect of water on the alumina ceramics pores was studied under different laser electric currents and processing environments. The results show that the taper angle of repeat drilling is obviously reduced from 4 to 2.5°, whether in the air or in static water. The slag, recast layer, and microcracking of the pore walls are also remarkably reduced under the condition of static water without a visible ablation phenomenon. The roundness of the pore is obviously improved from 0.9 to 0.98 with the mist-blowing method. The pore quality can be dramatically improved by using the method of repeat drilling in water with electric current of 160 A. [ABSTRACT FROM AUTHOR]

NaScMoO:RE (RE = Tb, Eu, Tb/Eu, Yb/Er, Yb/Ho) phosphors were successfully synthesized by surfactant-free hydrothermal method and post-calcination treatment. The energy transfer (ET) of MoO → Tb → Eu was proved by photoluminescence spectra and decay features. Multicolor emissions (green → yellow → red) were obtained by adjusting the ratio of Tb/Eu upon excitation into the MoO at 292 nm. The ET of Tb → Eu was demonstrated to be a resonant type via a dipole-dipole mechanism, and the crystal distance ( R ) was calculated by the quenching concentration method. Under 980 nm excitation, the emission of NaScMoO:RE (RE = Yb/Er, Yb/Ho) showed strong green (Yb/Er: S, H → I; Yb/Ho: S → I) luminescence, respectively. Moreover, the doping concentration of the Yb has been optimized under a fixed concentration of Er and Ho, respectively. The NaScMoO:RE phosphors have potential applications for color displays and light-emitting devices due to a variety of luminous colors. [ABSTRACT FROM AUTHOR]

Boron trifluoride-mediated transformation of tetrahydrofuran to corresponding N-aryl-substituted pyrrolidines is conducted under mild reaction conditions, providing a practical synthetic method with reasonable yields. Computational studies confirmed the reaction mechanism involving a fast Lewis acid-assisted ring-opening step, followed by the 7-membered intermediate formation and a ringclosing process as the rate-determining step. [ABSTRACT FROM AUTHOR]

Suburban areas have become rapid development zones during China's current urbanization. Generally, these areas are also regional precipitation centers that are prone to flood disasters. Therefore, it is important to assess the flood risk in suburban areas. In this study, flood risk was defined as the product of hazard and vulnerability based on disaster risk theory. A risk assessment index system was established, and the analytic hierarchy process method was used to determine the index weight. The Fangshan District in Beijing, China, which is an example of a typical suburban area undergoing rapid urbanization, was selected for this study. Six factors were considered in relation to hazard, and three factors were considered for vulnerability. Each indicator was discretized, standardized, weighted, and then combined to obtain the final flood risk map in a geographical information system environment. The results showed that the high and very high risk zones in the Fangshan District were primarily concentrated on Yingfeng Street, Xingcheng Street, Xincheng Street, and Chengguanzhen Street. The comparison to an actual flood disaster suggested that the method was effective and practical. The method can quantitatively reflect the relative magnitude and spatial distribution patterns of flood risk in a region. The method can be applied easily to most suburban areas in China for land use planning and flood risk management. [ABSTRACT FROM AUTHOR]

The effect of hydrogen charging on the stress corrosion cracking (SCC) behavior of 2205 duplex stainless steel (DSS) under 3.5 wt.% NaCl thin electrolyte layer was investigated on precharged samples through hydrogen determination, electrochemical measurement, and slow strain rate tensile test. Results show that hydrogen charging weakens the passive film without inducing any obvious trace of localized anodic dissolution. Therefore, hydrogen charging increases the SCC susceptibility of 2205 DSS mainly through mechanism of hydrogen embrittlement rather than mechanism of localized anodic dissolution. 2205 DSS shows a more susceptibility to hydrogen under the TEL when hydrogen charging current density (HCCD) is between 20 and 50 mA cm. The increasing trend is remarkable when hydrogen charging current density increases from 20 to 50 mA cm and fades after 50 mA cm. [ABSTRACT FROM AUTHOR]

CaF:Ln (Ln = Ce, Tb, Eu) phosphors with highly uniform shapes have been successfully synthesized by a simple hydrothermal method directly. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and lifetime. The results indicated that the pH values, organic additive and reaction time have a significant effect on the morphology and dimensions of CaF microcrystals and the possible formation mechanism was also proposed. Furthermore, the energy transfer from Ce to Tb and from Tb to Eu and from Ce to Tb to Eu was observed and the corresponding mechanisms were discussed in detail. The CaF:Ln phosphors may have potential optical applications in near-UV and violet LEDs. [ABSTRACT FROM AUTHOR]

These authors contributed equally: Shun Zhang and Ping Chen. After the publication, the first author reached out to the Editors to point out that that the phase contrast microscopy image in Figure 3(b) appears to replicate panels that originally appeared in Figure 2(b) of[1], which reports a different experiment by different authors. [Extracted from the article]

This meta-analysis examined the relationship between learning outcomes of children and educational involvement of parents during a unique period of early childhood education and early elementary education based on 100 independent effect sizes from 46 studies. Learning outcomes are academic achievement, and frameworks of parental involvement measure family involvement and partnership development. The relationship (with adjustment over frameworks and study features) indicated a strong and positive correlation (.509) between learning outcomes and parental involvement. Although types of parental (behavioral, personal, and intellectual) involvement and building institutional capacity demonstrated the greatest importance to the relationship, the role of parents (family involvement) was more important than the role of schools and communities (partnership development). For a strong relationship, behavioral involvement, home supervision, and home-school connection were the keys from family involvement, whereas capacity to engage parents, respectful and effective leadership in relation to families and children, and institutionalized authentic partnerships were the keys from partnership development. [ABSTRACT FROM AUTHOR]

In the present study, a cell-penetrating peptide, the transactivating transcriptional factor (TAT) domain from HIV, was linked to PEGylated multi-walled carbon nanotubes (MWCNTs) to develop a highly effective antitumor drug delivery system. FITC was conjugated on MWCNTs-polyethylene glycol (PEG) and MWCNTs-PEG-TAT to provide fluorescence signal for tracing the cellular uptake of the nanocarrier. After loaded with an anticancer agent, doxorubicin (DOX) via π − π stacking interaction, the physicochemical characteristics, release profile and biological evaluation of the obtained nano-sized drug carrier were investigated. The DOX loaded MWCNTs-PEG and MWCNTs-PEG-TAT drug carriers both displayed appropriate particle size, excellent stability, high drug loading, and pH-dependent drug release profile. Nevertheless, compared with DOX-MWCNTs-PEG, DOX-MWCNTs-PEG-TAT showed improved cell internalization, intracellular distribution and potentiated anticancer efficacy due to the TAT-mediated membrane translocation, endosomal escape and nuclear targeting. Furthermore, the therapeutic efficacy of DOX was not compromised after being conjugated with MWCNTs-PEG-TAT and the proposed nanocarrier was also confirmed to have a good biocompatibility. In conclusion, our results suggested that the unique combination of TAT and MWCNTs as a multifunctional drug delivery system might be a powerful tool for improved anticancer drug development. [ABSTRACT FROM AUTHOR]

Sewage sludge treatment is becoming one of the most significant challenges for domestic wastewater management. Optimization of sludge management for reducing sludge handling cost in wastewater treatment plant is highly demanded. Sludge treatment reed bed system (STRB) is an eco-environmentally friendly technology which has a low investment input and reduced costs for operation and maintenance. The objective of this study is to evaluate the effect of earthworm assistant STRB in terms of sludge dewatering and stabilization of surplus sludge. The results show that draining and evapotranspiration (ET) take the main role for sludge dewatering; with maximum of 77 and 43 % water was removed through draining and ET, respectively. Plants improved ET rate up to 13.1 % in the planted STRB compare with the unplanted STRB. The combination of plants and earthworms increased ET rate of 20.9 % more than the control STRB (unplanted without earthworms). The planted STRB with earthworm reached the lowest water content in accumulated sludge of 46 %. There was a systematic increase of total solids (TS) concentration from 0.5 % in the influent to 25-54 % in the accumulated sludge. Earthworms enhanced the sludge stabilization dramatic with the ratio of volatile solids (VS)/TS decreased from 49 % in the influent to 18 % in the accumulated sludge in the earthworm assistant STRB. The results demonstrated a good efficiency for sludge dewatering and stabilization with the assistant of earthworms in STRBs, which can be an alternative technology for sludge treatment in wastewater treatment plants. [ABSTRACT FROM AUTHOR]

Gastric cancer is the fourth most common cancer worldwide, with a low 5-year survival rate. Epigenetic modification plays pivotal roles in gastric cancer development. However, the role of histone-modifying enzymes in gastric cancer remains largely unknown. Here we report that Sirt7, a NAD+-dependent class III histone deacetylase, is over-expressed in human gastric cancer tissues. Sirt7 level is significantly correlated with disease stage, metastasis and survival. Knockdown of Sirt7 in gastric cancer cells inhibits cell proliferation and colony formation in vitro. In vivo subcutaneous xenograft results also show that Sirt7 knockdown can markedly repress gastric cancer cell growth. In addition, Sirt7 depletion induces apoptosis in gastric cancer cells via up-regulating expression of pro-apoptotic proteins and down-regulating anti-apoptotic proteins. Mechanically, Sirt7 binds to the promoter of miR-34a and deacetylases the H3K18ac, thus represses miR-34a expression. Reversely, depletion of miR-34a inhibits gastric cancer apoptosis induced by Sirt7 knockdown and restores cellular capacity of proliferation and colony formation. miR-34a depletion reduces Sirt7-knockdown-induced arrest of gastric growth. Finally, miR-34a is tightly associated with survival of patients with gastric cancer. [ABSTRACT FROM AUTHOR]

Crystalline Tb(CO): Eu samples were successfully synthesized by the precipitation reaction of rare-earth chloride with ammonium bicarbonate in solution directly under mild condition without further thermal treatment. The samples were characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, thermogravimetry analysis, Fourier transform infrared spectroscopy, photoluminescence, as well as lifetimes. Influences of pH, molar ratio of precipitant to rare earth ions, aging time, temperature, and surfactant on the morphology and crystal structure were investigated in detail. The obtained samples presented dumbbell-like microstructures which were assembled from nanosheets with the assistance of ethylene glycol. Under the excitation of 220-nm ultraviolet light, the Tb(CO) samples showed the characteristic emissions of Tb corresponding to D → F transitions, whereas the Tb(CO): Eu samples mainly exhibited the characteristic emissions of Eu corresponding to D → F transitions due to an effective energy transfer from Tb to Eu. The energy transfer efficiency from Tb to Eu increased with Eu doping concentration. The multicolor emission of Tb(CO): Eu samples can be tuned from green to red easily by altering the doping concentration of Eu. The materials are expected to apply widely in the future, and the simple method is particularly suitable for large-scale industrial production. [ABSTRACT FROM AUTHOR]

This work reports the gold-coated self-organized silicon nanopyramidal array prepared by a wet etching and magnetron sputtering process at room temperature. Scanning electron microscopy was used to detect the morphology of gold films. The surface-enhanced Raman scattering (SERS) spectra of the rhodamine 6G (R6G) molecules adsorbed on a nanoscale gold film were recorded. Experimental results show the relationships between gold film thickness and SERS intensity. A full three-dimensional finite difference time domain calculations were carried out, which compare the experimental results and show agreement with ratios of the SERS enhancement for the different thicknesses of gold films. Furthermore, numerical simulations of the array were conducted for both a real gold metal coating and a perfect electrical conductor to determine whether the SERS enhancement was due to diffraction or plasmonic effects. The sample with the fast fabrication process used in this work could provide a new way to obtain a uniform enhancement and low cost SERS substrate. [ABSTRACT FROM PUBLISHER]

Hexagonal vaterite-type LuBO:Tb/Eu lantern-like phosphors have been successfully prepared by a simple hydrothermal process directly without sintering treatment. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, photoluminescence, low-voltage cathodoluminescence, and kinetic decays were used to characterize as-prepared phosphors, which present complex lantern-like 3D assemblies that are composed of nanosheets with thickness of about 23 nm and high crystallinity in spite of the moderate reaction temperature of 210 °C. The reaction mechanism and the self-assembly evolution process have been proposed. The pH, temperature, time, and ethylene glycol play critical roles in the formation of this specific hierarchical and complex 3D structure. Under UV excitation and low-voltage electron beam excitation, vaterite-type LuBO:Tb samples showed the characteristic green emission of Tb corresponding to D → F transitions; vaterite-type LuBO:Eu particles exhibited a strong red emission corresponding to primary group electric dipole transition D → F with much higher R/O values (chromatically redder fluorescence, increase of 29 %) compared with samples by conventional solid-state reaction, which have potential applications in fluorescent lamps and field emission displays. [ABSTRACT FROM AUTHOR]

β-arrestins, including β-arrestin1 and β-arrestin2, are ubiquitous cytosolic proteins which localize in the cytoplasm and plasma membrane, initially be regarded as an potential character in G protein-coupled receptors (GPCR) desensitization, sequestration, and internalization. Besides, recent many studies increasingly revealed that β-arrestins served widely as versatile adapter proteins for scaffolding many intracellular signaling networks to modulate the strength and duration of signaling by diverse types of receptors and downstream kinases. As we known, the biologic and clinical behaviors of many tumors are largely determined by multiple molecular signal pathways. More recently, accumulating evidences established that β-arrestins got widely involved in many cancer developmental signaling events which responsible for tumor viability and metastasis, suggesting an impressive role of β-arrestins in tumor progression. Because of the regulation and biological output of β-arrestins is so complex, the role of β-arrestins in cancer development still remains enigmatic. However, the further understanding with the clinical prognosis and oncogenic potential of β-arrestins might facilitate the identification of diagnosis biomarkers and development of drug targets in cancer. In this article, we reviewed a comprehensive summary of the β-arrestins-mediated functions in human cancers. [ABSTRACT FROM AUTHOR]

As the largest wetland in the North China Plain (NCP), the Baiyangdian Lake plays an important role in maintaining water balance and ecological health of NCP. In the past few decades, the decreasing streamflow in the Baiyangdian Basin associated with climate variability and human activities has caused a series of water and eco-environmental issues. In this study, we quantified the impacts of climate variability and human activities on streamflow in the water source area of the Baiyangdian Lake, based on analyses of hydrologic changes of the upper Tanghe river catchment (a sub-basin of the Baiyangdian Basin) from 1960 to 2008. Climate elasticity method and hydrological modeling method were used to distinguish the effects of climate variability and human activities. The results showed that the annual streamflow decreased significantly (P>0.05) by 1.7 mm/a and an abrupt change was identified around the year 1980. The quantification results indicated that climate variations accounted for 38%-40% of decreased streamflow, while human activities accounted for 60%-62%. Therefore, the effect of human activities played a dominant role on the decline of the streamflow in the water source area of the Baiyangdian Lake. To keep the ecosystem health of the Baiyangdian Lake, we suggest that minimum ecological water demand and integrated watershed management should be guaranteed in the future. [ABSTRACT FROM AUTHOR]

Simulated rainfall is a valid tool to examine the runoff generation on the slope. 13 simulated rainfall experiments with different rainfall intensities and durations are completed in a 5 m × 10 m experimental plot in mountainous area of North China. Simultaneously, rainfall, surface runoff, soil-layer flow, mantel-layer flow and soil moisture are monitored respectively. From the results, it is found that the hydrographs in all layers have the characteristics of rapid rise and fall. The recessions of surface flow and soil-layer flow are much faster than that of mantel-layer flow. Surface flow, the main contributor, makes up more than 60% of the total runoff in the study area. It even exceeds 90% in the cases of high intensity rainfall events. Runoff coefficient (ratio of total runoff to rainfall amount) is mainly influenced by rainfall amount, rainfall intensity and antecedent soil moisture, and the relationship can be well expressed by a multiple linear regression function α = 0.002 P + 0.182 i + 4.88 W a − 0.821. The relation between the rainfall intensity and the lag time of three flows (surface runoff, soil-layer flow and mantel-layer flow) is shown to be exponential. Then, the result also shows that the recession constant is 0.75 for surface runoff, is 0.94 for soil-layer and mantel-layer flow in this area. In this study area, the dominant infiltration excess runoff is simulated by Horton model. About 0.10 mm/min percolation is observed under the condition of different rainfall intensities, therefore the value is regarded as the steady infiltration rate of the study area. [ABSTRACT FROM AUTHOR]

T cell infiltration to synovial tissue is an early pathogenic mechanism of rheumatoid arthritis (RA). In the present work, we reveal that G protein coupled receptor kinase 2 (GRK2) is abundantly expressed in T cells of collagen-induced arthritis (CIA). A GRK2 inhibitor, paroxetine protects the joints from inflammation and destruction, primarily through inhibition of both CD4+ helper T (Th) cell and CD8+ cytotoxic T (Tc) cell migration to synovial tissue. Meanwhile, paroxetine restores the balance of Th/Tc, effector Th (Theff)/ naïve Th (Thnaive) and effector Tc (Tceff)/ naïve Tc (Tcnaive) to equilibrium by elevating the frequency of Thnaive, Tcnaive and regulatory Th cells; reducing the increased Theff, activated Th and Tceff, having a similar effect as methotrexate (MTX). In addition, both serum and synovial IL-1β, TNF-α and CX3CL1 expression was effectively inhibited in treated rats. In vitro assay confirmed that paroxetine inhibits CX3CL1-induced T cell migration through blocking the activity of GRK2. Among three MAPK families, paroxetine was found to be able to decrease the phosphorylation of ERK. This study elucidates that paroxetine attenuates the symptoms of CIA rats due to its inhibitory effect on T cell activation and infiltration to synovial tissue via suppression of ERK pathway. [ABSTRACT FROM AUTHOR]