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Recently, the crystal structures and electrochemical properties of the isomers (Sc2S "trapped" in C82) have been reported, in which the SC2S is located inside the different positions of the C82 cage. In the present work, three isomers of endohedral metallofullerenes Sc2S@C3v(8)-C82 (A, B, and C) have been designed to explore the effect of the position of Sc2S on their interaction energies and nonlinear optical properties. Among three isomers, the Sc2S is located in different positions of the C82 cage: the angles of Sc–S–Sc in A, B, and C are 104.9, 114.8, and 115.7°, respectively. Furthermore, the analysis of natural bond orbital (NBO) charge indicates that the electron-transfer is from the Sc2S to the adjacent carbon atoms of the C82 cage. The interaction energy of B is the smallest among three isomers which is −226.2 kcal mol-1. It was worth mentioning that their first hyperpolarizabilities (βtot) were studied, we found that their βtot values were related to the positions of Sc2S: C (2100)>B (1191)>A (947 au). We hope that the present work can provide a new strategy to promote the nonlinear optical properties of endohedral metallofullerenes by changing the positions of the encapsulated molecular. [ABSTRACT FROM AUTHOR]

Genomic imprinting is a genetic phenomenon in which certain alleles are differentially expressed in a parent-of-origin-specific manner, and plays an important role in the study of complex traits. For a diallelic marker locus in human, the parental-asymmetry tests Q-PAT( c) with any constant c were developed to detect parent-of-origin effects for quantitative traits. However, these methods can only be applied to deal with nuclear families and thus are not suitable for extended pedigrees. In this study, by making no assumption about the distribution of the quantitative trait, we first propose the pedigree parental-asymmetry tests Q-PPAT( c) with any constant c for quantitative traits to test for parent-of-origin effects based on nuclear families with complete information from general pedigree data, in the presence of association between marker alleles under study and quantitative traits. When there are any genotypes missing in pedigrees, we utilize Monte Carlo (MC) sampling and estimation and develop the Q-MCPPAT( c) statistics to test for parent-of-origin effects. Various simulation studies are conducted to assess the performance of the proposed methods, for different sample sizes, genotype missing rates, degrees of imprinting effects and population models. Simulation results show that the proposed methods control the size well under the null hypothesis of no parent-of-origin effects and Q-PPAT( c) are robust to population stratification. In addition, the power comparison demonstrates that Q-PPAT( c) and Q-MCPPAT( c) for pedigree data are much more powerful than Q-PAT( c) only using two-generation nuclear families selected from extended pedigrees. [ABSTRACT FROM AUTHOR]

Genomic imprinting is an important epigenetic phenomenon in studying complex traits and has generally been examined by detecting parent-of-origin effects of alleles. The parental-asymmetry test (PAT) based on nuclear families with both parents and its extensions to deal with missing parental genotypes is simple and powerful for such a task. However, these methods only use case (affected) children in nuclear families and thus do not make full use of information on control (unaffected) children, if available, in these families. In this article, we propose a novel parent-of-origin effects test C-PATu (the combined test of PATu and 1-PATu) by using both the control and case children in nuclear families with one or both parents. C-PATu is essentially a weighted framework, in which the test based on all the control children and their parents and that based on all the case children and their parents are weighted according to the population disease prevalence. Simulation results demonstrate that the proposed tests control the size well under no parent-of-origin effects and using additional information from control children improves the power of the tests under the imprinting alternative. Application of C-PATu to a Framingham Heart Study data set further shows the feasibility in practical application of the test. [ABSTRACT FROM AUTHOR]

This paper presents a 2D analytical solution for the transverse velocity distribution in compound open channels based on the Shiono and Knight method (SKM), in which the secondary flow coefficient ( K-value) is introduced to take into account the effect of the secondary flow. The modeling results agree well with the experimental results from the Science and Engineering Research Council-Flood Channel Facility (SERC-FCF). Based on the SERC-FCF, the effects of geography on the secondary flow coefficient and the reason for such effects are analyzed. The modeling results show that the intensity of the secondary flow is related to the geometry of the section of the compound channel, and the sign of the K-value is related to the rotating direction of the secondary flow cell. This study provides a scientific reference to the selection of the K-value. [ABSTRACT FROM AUTHOR]

A new two-factor method based on the probability and the fuzzy sets theory is used for the analyses of the dynamic response and reliability of fuzzy-random truss systems under the stationary stochastic excitation. Considering the fuzzy-randomness of the structural physical parameters and geometric dimensions simultaneously, the fuzzy-random correlation function matrix of structural displacement response in time domain and the fuzzy-random mean square values of structural dynamic response in frequency domain are developed by using the two-factor method, and the fuzzy numerical characteristics of dynamic responses are then derived. Based on numerical characteristics of structural fuzzy-random dynamic responses, the structural fuzzy-random dynamic reliability and its fuzzy numerical characteristic are obtained from the Poisson equation. The effects of the uncertainty of the structural parameters on structural dynamic response and reliability are illustrated via two engineering examples and some important conclusions are obtained. [ABSTRACT FROM AUTHOR]

Recently, acetylcholinesterase (AChE) has been studied as an important apoptosis regulator. We previously showed that cellular calcium mobilization upregulated AChE expression by modulating promoter activity and mRNA stability. In this study, we have identified a potential Smad3/4 binding element, TGCCAGACA, located within the −601 to −571 bp fragment of the AChE promoter, as an important calcium response motif. Smad2/3 and Smad4 were shown to bind this element. Overexpression of human Smad3 increased AChE transcription activity in a dose-dependent manner in HeLa cells, whereas dominant-negative Smad3 blocked this activation. Upon A23187 and thapsigargin treatment, nuclear Smad3 accumulation was observed, an effect that was blocked by the intracellular Ca2+ chelator BAPTA–AM. Calcium-induced AChE transcriptional activation was significantly blocked when the nuclear localization signal of Smad3 was destroyed. Taken together, our data suggest Smad3 can regulate AChE transcriptional activation following calcium-induced nuclear accumulation. [ABSTRACT FROM AUTHOR]

Panax quinquefolium (American ginseng) is a perennial understory herb that has been widely used as a medicinal plant in China and other countries. Autotoxicity has been reported to be one of the major problems hindering the consecutive cultivation of American ginseng. However, the potential autotoxic compounds produced by the root of American ginseng are less well known. Here, we report the isolation and characterization of five groups of autotoxic compounds from aqueous extracts of the fibrous roots of American ginseng. Ether extracts of the water-soluble compounds were further analyzed and separated into seven fractions. Among them, the most autotoxic fraction (Fraction V) was subjected to GC/MS analysis, and 44 compounds were identified. Based on literature information, 14 individual compounds were selected and their autotoxic effects on seedling growth were further tested. The results revealed that, of these 14 compounds, 9 phenolic compounds significantly reduced the growth of seedlings in a concentration-dependent manner, while 5 aliphatic compounds showed modest inhibition at all three concentrations tested. Furthermore, we verified the existence of the autotoxic compounds in the plow layer soil of commercially cultivated American ginseng fields, and the concentration of these compounds as determined by HPLC analysis was in line with the concentration determined to be bioactive. Taken together, our study established a functional link between the compounds produced by American ginseng and their autotoxic effects. [ABSTRACT FROM AUTHOR]

A new method called the interval factor method for the finite element analysis of truss structures with interval parameters is presented in this paper. The structural parameters and applied forces can be considered as interval variables by using the interval factor method, the structural stiffness matrix can then be divided into the product of two parts corresponding to the interval factors and the deterministic value. From the static governing equations of interval finite element method of structures, the structural displacement and stress responses are expressed as the functions of the interval factors. The computational expressions for lower and upper bounds, mean value and interval change ratio of structural static responses are derived by means of the interval operations. The effect of the uncertainty of the structural parameters and applied forces on the structural displacement and stress responses is demonstrated by truss structures. [ABSTRACT FROM AUTHOR]

A boundary value problems for functional differenatial equations, with nonlinear boundary condition, is studied by the theorem of differential inequality. Using new method to construct the upper solution and lower solution, sufficient conditions for the existence of the problems' solution are established. A uniformly valid asymptotic expansions of the solution is also given. [ABSTRACT FROM AUTHOR]

The problem of periodic solutions for a kind of kth-order linear neutral functional differential equation is studied. By using the theory of Fourier expansions, a sufficient and necessary condition to guarantee the existence and uniqueness of periodic solution is obtained. Further, by applying this result and Schauder's fixed point principle, a kind of kth-order nonlinear neutral functional differential equation is investigated, and some new results on existence of the periodic solutions are given as well. These results improve and extend some known results in recent literature. [ABSTRACT FROM AUTHOR]

A class of second-order neutral equations with deviating arguments are studied, and sufficient conditions are derived for every solution to be oscillatory. [ABSTRACT FROM AUTHOR]

Mature dendritic cells (DCs) home to secondary lymphoid organs through CC chemokine receptor 7 (CCR7). Exosomes derived from DCs (DC-exos) are reported to migrate to spleen and induce inflammation in vivo. In this study, we demonstrated that mature bone marrow DC-exos can activate immature DC and T cells in vitro. Then we intravenously injected DC-exos into C57BL/6 mice, observing that mature DC-exos accumulated more in spleen than immature DC-exos. These DC-exos in spleen could be uptaken by splenetic DCs and T cells and induce an inflammatory response. We further showed that the increased accumulation of mature DC-exos in spleen was regulated by CCR7, whose reduction led to a decrease of accumulation in spleen and attenuated inflammatory response in serum. These data provide us a new perspective to comprehensively understand exosomes, which might inherit some special functions from their parent cells and exert these functions in vivo. [ABSTRACT FROM AUTHOR]

The article discusses various reports on measurement technology and manufacturing engineering published within the issue, including one on form profile measurement of micro aspheric surface, one on measurement error processing, and one on optical defect detection of next generation semiconductor wafer.

Studies have shown that Tai Chi and conventional exercise can modify the brain through distinct mechanisms, resulting in different brain adaptations. Therefore, it is conceivable to speculate that these two exercise modalities may have different effects on improving cognitive function. This study was a parallel group, assessor-blinded, pilot randomized controlled trial comparing the effects of Tai Chi and conventional exercise on improving cognitive function in older persons with mild cognitive impairment (MCI). A total of 34 adults aged ≥ 50 years with MCI were randomized (1:1:1) to the Tai Chi group (TC, n = 10, 3 sessions of 60-min Yang-style Tai Chi training per week for 24 weeks), conventional exercise group (EX: n = 12, 3 sessions of 60-min fitness training per week for 24 weeks), or control group (CON: n = 12, no intervention). Global cognitive function assessed by the Hong Kong version of the Montreal Cognitive Assessment (MoCA-HK) and performance in various cognitive domains were examined at baseline, and 12 and 24 weeks of the intervention. Both exercise groups showed improved global cognitive function as measured by MoCA-HK compared with the control group after 12 and 24 weeks of the intervention, (all P < 0.001). Only TC achieved clinically relevant improvement on global cognitive function at week 12. Both exercise groups achieved clinically relevant improvements at the end of the interventions at week 24. Compared with EX, TC exhibited greater improvements on global cognitive function indicated by MoCA-HK after 12 weeks of the intervention (P < 0.001) and cognitive flexibility indicated by part B/A ratio score of the Trail Making Test throughout the study (all P < 0.05). Both interventions were equally effective in improving the other examined cognitive domains. Further studies are needed to substantiate the superior long-term benefits of Tai Chi on global cognitive function compared with conventional exercise, and dissect the underlying mechanisms of the two exercises on improving cognitive domains and the corresponding brain adaptations. Trial registration: This study was registered at clinicaltrials.gov (Trial registration number: NCT04248400; first registration date: 30/01/2020). [ABSTRACT FROM AUTHOR]

This paper discusses dynamic modeling, controller design, simulation, and experiment for a non-contact three-degree-of-freedom planar motion stage for precision measurement and control of positions. A simplified model of this planar motion stage driven by four permanent magnetic linear motors is established on an assumption that the influence of the small yawing motion on the electromagnetic characteristics of the planar motion stage can be neglected. Overall control strategy, including a fine-tuned proportional integral derivative component to yield basic dynamic performance and a component derived from sliding mode observer to estimate and compensate for modeling uncertainties and disturbances, is developed and implemented in a digital signal processor. Simulation study and experimental results of using a three-axis interferometer as the position sensor are presented to verify the effectiveness of the suggested dynamic compensation strategy and tracking performance of the non-contact planar motion stage. [ABSTRACT FROM AUTHOR]

A new triple fixed-point theorem is applied to investigate the existence of at least triple positive solutions of fourth-order four-point boundary value problems for p-Laplacian dynamic equations on a time scale. The interesting point is that we choose an inversion technique employed by Avery and Peterson in 1998. [ABSTRACT FROM AUTHOR]

Using nanomaterials to develop multimodal systems has generated cutting-edge biomedical functions. Herein, we develop a simple chemical-vapor-deposition method to fabricate graphene-isolated-Au-nanocrystal (GIAN) nanostructures. A thin layer of graphene is precisely deposited on the surfaces of gold nanocrystals to enable unique capabilities. First, as surface-enhanced-Raman-scattering substrates, GIANs quench background fluorescence and reduce photocarbonization or photobleaching of analytes. Second, GIANs can be used for multimodal cell imaging by both Raman scattering and near-infrared (NIR) two-photon luminescence. Third, GIANs provide a platform for loading anticancer drugs such as doxorubicin (DOX) for therapy. Finally, their NIR absorption properties give GIANs photothermal therapeutic capability in combination with chemotherapy. Controlled release of DOX molecules from GIANs is achieved through NIR heating, significantly reducing the possibility of side effects in chemotherapy. The GIANs have high surface areas and stable thin shells, as well as unique optical and photothermal properties, making them promising nanostructures for biomedical applications. [ABSTRACT FROM AUTHOR]

The existence of a complex relationship between soil microbes and ginsenoside contents in their host plants has been reported by previous studies. Here, we analyzed the interaction between the root pathogens and the ginsenoside content in the roots of American ginseng. Two fungal pathogen species were isolated from diseased American ginseng roots, and identified as Fusarium oxysporum (isolate C1) and Fusarium solani (isolate F19) by molecular sequencing analysis. To determine the effect of Fusarium-mediated infection of American ginseng roots, the contents of three ginsenosides, ginsenosides Rb, ginsenosides Re and ginsenosides Rg, were monitored over a time course of 120 h post infection using high performance liquid chromatography (HPLC). We found that the level of Rb was rapidly upregulated upon fungal infection, whereas the contents of Re or Rg were not altered significantly. Furthermore, the presence of Rb, but not Re or Rg, significantly inhibited conidium germination of both Fusarium species. Thus, Rb is likely the disease-resistance compound produced by American ginseng roots in response to the pathogenic fungi. Our study is the first to report the three ginsenosides with different chemical structure respond differently to soilborne pathogen infection. [ABSTRACT FROM AUTHOR]