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Background: Mediation analysis is a powerful tool to identify factors mediating the causal pathway of exposure to health outcomes. Mediation analysis has been extended to study a large number of potential mediators in high-dimensional data settings. The presence of confounding in observational studies is inevitable. Hence, it's an essential part of high-dimensional mediation analysis (HDMA) to adjust for the potential confounders. Although the propensity score (PS) related method such as propensity score regression adjustment (PSR) and inverse probability weighting (IPW) has been proposed to tackle this problem, the characteristics with extreme propensity score distribution of the PS-based method would result in the biased estimation. Methods: In this article, we integrated the overlapping weighting (OW) technique into HDMA workflow and proposed a concise and powerful high-dimensional mediation analysis procedure consisting of OW confounding adjustment, sure independence screening (SIS), de-biased Lasso penalization, and joint-significance testing underlying the mixture null distribution. We compared the proposed method with the existing method consisting of PS-based confounding adjustment, SIS, minimax concave penalty (MCP) variable selection, and classical joint-significance testing. Results: Simulation studies demonstrate the proposed procedure has the best performance in mediator selection and estimation. The proposed procedure yielded the highest true positive rate, acceptable false discovery proportion level, and lower mean square error. In the empirical study based on the GSE117859 dataset in the Gene Expression Omnibus database using the proposed method, we found that smoking history may lead to the estimated natural killer (NK) cell level reduction through the mediation effect of some methylation markers, mainly including methylation sites cg13917614 in CNP gene and cg16893868 in LILRA2 gene. Conclusions: The proposed method has higher power, sufficient false discovery rate control, and precise mediation effect estimation. Meanwhile, it is feasible to be implemented with the presence of confounders. Hence, our method is worth considering in HDMA studies. [ABSTRACT FROM AUTHOR]

This work focuses on the optimal control design for suppressing the singularity formation in chemotaxis governed by the parabolic-elliptic Patlak–Keller–Segel (PKS) system via flow advection. The main idea of this work lies in utilizing flow advection for enhancing diffusion as to control the nonlinear behavior of the system. The objective is to determine an optimal strategy for adjusting flow strength so that the possible finite time blow-up of the solution can be suppressed. Rigorous proof of the existence of an optimal solution and derivation of first-order optimality conditions for solving such a solution are presented. Spline collocation methods are employed for solving the optimality conditions. Numerical experiments based on 2D cellular flows in a rectangular domain are conducted to demonstrate our ideas and designs. [ABSTRACT FROM AUTHOR]

Background: Outliers, data points that significantly deviate from the norm, can have a substantial impact on statistical inference and provide valuable insights in data analysis. Multiple methods have been developed for outlier detection, however, almost all available approaches fail to consider the spatial dependence and heterogeneity in spatial data. Spatial data has diverse formats and semantics, requiring specialized outlier detection methodology to handle these unique properties. For now, there is limited research exists on robust spatial outlier detection methods designed specifically under the spatial error model (SEM) structure. Method: We propose the Spatial-Θ-Iterative Procedure for Outlier Detection (Spatial-Θ-IPOD), which utilizes a mean-shift vector to identify outliers within the SEM. Our method enables an effective detection of spatial outliers while also providing robust coefficient estimates. To assess the performance of our approach, we conducted extensive simulations and applied it to a real-world empirical study using life expectancy data from multiple countries. Results: Simulation results showed that the masking and JD (Joint Detection) indicators of our Spatial-Θ-IPOD method outperformed several commonly used methods, even in high-dimensional scenarios, demonstrating stable performance. Conversely, the Θ-IPOD method proved to be ineffective in detecting outliers when spatial correlation was present. Moreover, our model successfully provided reliable coefficient estimation alongside outlier detection. The proposed method consistently outperformed other models (both robust and non-robust) in most cases. In the empirical study, our proposed model successfully detected outliers and provided valuable insights in the modeling process. Conclusions: Our proposed Spatial-Θ-IPOD offers an effective solution for detecting spatial outliers for SEM while providing robust coefficient estimates. Notably, our approach showcases its relative superiority even in the presence of high leverage points. By successfully identifying outliers, our method enhances the overall understanding of the data and provides valuable insights for further analysis. [ABSTRACT FROM AUTHOR]

For complex networked systems, based on the consideration of nonlinearity and causality, a novel general method of nonlinear causal network learning, termed extreme support vector regression Granger causality (ESVRGC), is proposed. The nonuniform time-delayed influence of the driving nodes on the target node is particularly considered. Then, the restricted model and the unrestricted model of Granger causality are, respectively, formulated based on extreme support vector regression, which uses the selected time-delayed components of system variables as the inputs of kernel functions. The nonlinear conditional Granger causality index is finally calculated to confirm the strength of a causal interaction. Generally, based on the simulation of a nonlinear vector autoregressive model and nonlinear discrete time-delayed dynamic systems, ESVRGC demonstrates better performance than other popular methods. Also, the validity and robustness of ESVRGC are also verified by the different cases of network types, sample sizes, noise intensities, and coupling strengths. Finally, the superiority of ESVRGC is successful verified by the experimental study on real benchmark datasets. [ABSTRACT FROM AUTHOR]

This work is concerned with nonlinear feedback control design for the problem of fluid mixing via advection. The overall dynamics is governed by the transport and Stokes equations in an open bounded and connected domain Ω ⊂ R d , with d = 2 or d = 3. The feedback laws are constructed based on the ideas of instantaneous control as well as a direct approximation of the optimality system derived from an optimal open-loop control problem. It can be shown that under appropriate numerical discretization schemes, two approaches generate the same sub-optimal feedback law. On the other hand, different discretization schemes may result in feedback laws of different regularity, which determine different mixing results. The Sobolev norm of the dual space (H 1 (Ω)) ′ of H 1 (Ω) is used as the mix-norm to quantify mixing based on the known property of weak convergence. The major challenge is encountered in the analysis of the asymptotic behavior of the closed-loop systems due to the absence of diffusion in the transport equation together with its nonlinear coupling with the flow equations. To address these issues, we first establish the decay properties of the velocity, which in turn help obtain the estimates on scalar mixing and its long-time behavior. Finally, mixed continuous Galerkin (CG) and discontinuous Galerkin (DG) methods are employed to discretize the closed-loop system. Numerical experiments are conducted to demonstrate our ideas and compare the effectiveness of different feedback laws. [ABSTRACT FROM AUTHOR]

Background: Predicting cognition decline in patients with mild cognitive impairment (MCI) is crucial for identifying high-risk individuals and implementing effective management. To improve predicting MCI-to-AD conversion, it is necessary to consider various factors using explainable machine learning (XAI) models which provide interpretability while maintaining predictive accuracy. This study used the Explainable Boosting Machine (EBM) model with multimodal features to predict the conversion of MCI to AD during different follow-up periods while providing interpretability. Methods: This retrospective case-control study is conducted with data obtained from the ADNI database, with records of 1042 MCI patients from 2006 to 2022 included. The exposures included in this study were MRI biomarkers, cognitive scores, demographics, and clinical features. The main outcome was AD conversion from aMCI during follow-up. The EBM model was utilized to predict aMCI converting to AD based on three feature combinations, obtaining interpretability while ensuring accuracy. Meanwhile, the interaction effect was considered in the model. The three feature combinations were compared in different follow-up periods with accuracy, sensitivity, specificity, and AUC-ROC. The global and local explanations are displayed by importance ranking and feature interpretability plots. Results: The five-years prediction accuracy reached 85% (AUC = 0.92) using both cognitive scores and MRI markers. Apart from accuracies, we obtained features' importance in different follow-up periods. In early stage of AD, the MRI markers play a major role, while for middle-term, the cognitive scores are more important. Feature risk scoring plots demonstrated insightful nonlinear interactive associations between selected factors and outcome. In one-year prediction, lower right inferior temporal volume (<9000) is significantly associated with AD conversion. For two-year prediction, low left inferior temporal thickness (<2) is most critical. For three-year prediction, higher FAQ scores (>4) is the most important. During four-year prediction, APOE4 is the most critical. For five-year prediction, lower right entorhinal volume (<1000) is the most critical feature. Conclusions: The established glass-box model EBMs with multimodal features demonstrated a superior ability with detailed interpretability in predicting AD conversion from MCI. Multi features with significant importance were identified. Further study may be of significance to determine whether the established prediction tool would improve clinical management for AD patients. [ABSTRACT FROM AUTHOR]

Since most patients with heart failure are re-admitted to the hospital, accurately identifying the risk of re-admission of patients with heart failure is important for clinical decision making and management. This study plans to develop an interpretable predictive model based on a Chinese population for predicting six-month re-admission rates in heart failure patients. Research data were obtained from the PhysioNet portal. To ensure robustness, we used three approaches for variable selection. Six different machine learning models were estimated based on selected variables. The ROC curve, prediction accuracy, sensitivity, and specificity were used to evaluate the performance of the established models. In addition, we visualized the optimized model with a nomogram. In all, 2002 patients with heart failure were included in this study. Of these, 773 patients experienced re-admission and a six-month re-admission incidence of 38.61%. Based on evaluation metrics, the logistic regression model performed best in the validation cohort, with an AUC of 0.634 (95%CI: 0.599–0.646) and an accuracy of 0.652. A nomogram was also generated. The established prediction model has good discrimination ability in predicting. Our findings are helpful and could provide useful information for the allocation of healthcare resources and for improving the quality of survival of heart failure patients. [ABSTRACT FROM AUTHOR]

In the indoor laser simulation localization and mapping (SLAM) system, the signal emitted by the LiDAR sensor is easily affected by lights and objects with low reflectivity during the transmission process, resulting in more noise points in the laser scan. To solve the above problem, this paper proposes a clustering noise reduction method based on keyframe extraction. First, the dimension of a scan is reduced to a histogram, and the histogram is used to extract the keyframes. The scans that do not contain new environmental information are dropped. Secondly, the laser points in the keyframe are divided into different regions by the region segmentation method. Next, the points are separately clustered in different regions and it is attempted to merge the point sets from adjacent regions. This greatly reduces the dimension of clustering. Finally, the obtained clusters are filtered. The sets with the number of laser points lower than the threshold will be dropped as abnormal clusters. Different from the traditional clustering noise reduction method, the technique not only drops some unnecessary scans but also uses a region segmentation method to accelerate clustering. Therefore, it has better real-time performance and denoising effect. Experiments on the MIT dataset show that the method can improve the trajectory accuracy based on dropping a part of the scans and save a lot of time for the SLAM system. It is very friendly to mobile robots with limited computing resources. [ABSTRACT FROM AUTHOR]

Summary: A novel method is proposed to locate sources with uniform circular array (UCA) in the presence of channel phase errors. Inspired by the rank reduction (RARE) theory in the spatial domain, which creates the necessary condition (reduction rank vector) with the instrumental sensors, a reduction in the aperture of UCA is considered for the construction of the reduction rank vector that is related only to the source location in the UCA‐mode domain based on the relationship between the order and the independent variable of the Bessel function. This indicates that the source location and the channel phase errors can be decoupled in the UCA‐mode domain, and then the optimization function that is only related to the channel phase errors is formulated with the reduction rank vector based on the RARE theory. Then with the channel phase errors calibrated, the source location can be estimated with the Vandemonde structure of the virtual steering vector via UCA‐ESPRIT. The proposed method requires no pre‐calibrated sensors or calibration sources. Also, it avoids the multi‐dimensional iteration. Results verify that the proposed method can perform approximately to calibration source method and instrumental sensor method via source separation, signal‐noise ratio (SNR), and snapshots experiments; furthermore, it is also verified that the proposed method can cope with more sources than the Schur‐product based method and it is superior to the Schur‐product based method in performance as it has a larger tolerance for the array aperture, while both of them are on‐line estimators. [ABSTRACT FROM AUTHOR]

FeVO4‐based catalysts with a wide temperature window and high SO2 tolerance have attracted increasing attention for the selective catalytic reduction of NOx with NH3. However, the alkali‐resistance of FeVO4‐based catalysts is still challenging. In this study, the K‐resistance of FeVO4/TiO2 was markedly improved via the Nb modification. It was demonstrated that the adsorption and reactivity of NH3/NH4+ and NOx species on K poisoned FeVO4/TiO2 both decreased, which restrained the process of Langmuir‐Hinshelwood reaction path. As a comparison, more adsorption of NH3/NH4+ species and the higher reactivity with gaseous NO maintain the process of Eley‐Rideal reaction path, leading to a satisifactory SCR activity. This work demonstrated an effective route to improve alkali‐resistance via modulating reactivity and reaction path of adsorbed NH3/NH4+ and NOx species over Nb modified vanadate catalysts, which presented a new point for the development of high‐performance alkali‐resistant SCR catalysts. [ABSTRACT FROM AUTHOR]

This paper is concerned with a bilinear control problem for enhancing convection-cooling via an incompressible velocity field. Both optimal open-loop control and closed-loop feedback control designs are addressed. First and second order optimality conditions for characterizing the optimal solution are discussed. In particular, the method of instantaneous control is applied to establish the feedback laws. Moreover, the construction of feedback laws is also investigated by directly utilizing the optimality system with appropriate numerical discretization schemes. Computationally, it is much easier to implement the closed-loop feedback control than the optimal open-loop control, as the latter requires to solve the state equations forward in time, coupled with the adjoint equations backward in time together with a nonlinear optimality condition. Rigorous analysis and numerical experiments are presented to demonstrate our ideas and validate the efficacy of the control designs. [ABSTRACT FROM AUTHOR]

The problem of parameter identification appears in many physical applications. A parameter of particular interest in cancer treatment is permeability, which modulates the fluidic streamlines in the tumor microenvironment. Most of the existing permeability identification techniques are invasive and not feasible to identify the permeability with minimal interference with the porous structure in their working conditions. In this paper, a theoretical framework utilizing partial differential equation (PDE)-constrained optimization strategies is established to identify a spatially distributed permeability of a porous structure from its modulated external velocity field measured around the structure. In particular, the flow around and through the porous media are governed by the steady-state Navierâ€"Stokesâ€"Darcy model. The performance of our approach is validated via numerical and experimental tests for the permeability of a 3D printed porous surrogate in a micro-fluidic chip based on the sampled optical velocity measurement. Both numerical and experimental results show a high precision of the permeability estimation. [ABSTRACT FROM AUTHOR]

This work addresses an optimal bilinear control design representing the corrective maintenance for a reparable multi-state system. The primary interest is to optimise the availability of the system, which is defined as the probability that the system is operating properly when it is requested for use. The system model considered in our current work is governed by coupled transport and integro-differential equations. A corrective maintenance policy is represented by the repair rate, which depends on the distributed repair time. The objective is to determine an optimal repair rate that maximises the availability of the system in good mode over a given system running period. This essentially leads to a bilinear control problem set in a nonreflexive Banach space using L 1 -optimisation. A rigorous proof of existence of an optimal controller and the first-order necessary conditions of optimality are addressed. Numerical experiments are conducted to demonstrate the theoretical results. [ABSTRACT FROM AUTHOR]

The bicistronic expression system that utilizes fluorescent reporters has been demonstrated to be a straightforward method for detecting recombinant protein expression levels, particularly when compared to polyacrylamide gel electrophoresis and immunoblot analysis, which are tedious and labor-intensive. However, existing bicistronic reporter systems are less capable of quantitative measurement due to the lag in reporter expression and its negative impact on target protein. In this work, a plug and play bicistronic construct using mCherry as reporter was applied in the screening of optimal replicon and promoter for Sortase expression in Escherichia coli (E. coli). The bicistronic construct allowed the reporter gene and target open reading frame (ORF) to be co-transcribed under the same promoter, resulting in a highly positive quantitative correlation between the expression titer of Sortase and the fluorescent intensity (R2 > 0.97). With the correlation model, the titer of target protein can be quantified by noninvasively measuring the fluorescent intensity. On top of this, the expression of reporter has no significant effect on the yield of target protein, thus favoring a plug and play design for removing reporter gene to generate a plain plasmid for industrial use. • A plug and play design is applied to get a plasmid without the reporter gene affecting the the target protein expression. • The bicistronic reporter system enables the tight co-expression of the target gene (srtA) and the reporter (mCherry). • The linear regression model demonstrated that the protein expression can be quantified by reading the fluorescent intensity. [ABSTRACT FROM AUTHOR]

The convective heat transfer between wind and photovoltaic (PV) panels will cause fluctuations in the temperature and performance of PV cells, which have a great negative impact on the grid-connected solar energy. The development of large-scale PV power plants in desertification areas has certain advantages, but the output power fluctuations caused by windy-dusty environment will be more common and important. This paper established a new model of convective heat transfer coefficient with and without dust deposition. Results show that the convective heat transfer coefficient of PV panel is not only affected by wind speed and dust density, but also related to the tilt angle of panel. As the dust accumulation density increases, the convective heat transfer coefficient of the dusty PV panel firstly increasing and then decreasing, and the maximum value appears when the dust deposition density is 20 g/m2. In addition, the average heat transfer coefficient of dusty PV module is slightly higher than that of clean PV panels by 4.13%, which can be revealed by the thermal diffusivity. This work confirms the influence of dust on the convective heat transfer characteristics, and provides an important basis for establishing a more practical PV panel temperature prediction model. [ABSTRACT FROM AUTHOR]

New human life begins in the uterus in a period of both extreme plasticity and sensitivity to environmental disturbances. The fetal stage is also a vital period for central nervous system development, with experiences at this point profoundly and permanently shaping brain structure and function. As such, some brain disorders may originate in utero. Glucocorticoids, a class of essential stress hormones, play indispensable roles in fetal development, but overexposure may have lasting impacts on the brain. In this review, we summarize data from recent clinical and non-clinical studies regarding alterations in fetal brains due to prenatal glucocorticoid overexposure that are associated with nervous system disorders. We discuss relevant changes to brain structure and cellular functions and explore the underlying molecular mechanisms. In addition, we summarize factors that may cause differential outcomes between varying brain regions, and outline clinically feasible intervention strategies that are expected to minimize negative consequences arising from fetal glucocorticoid overexposure. Finally, we highlight the need for experimental evidence aided by new technologies to clearly determine the effects of excessive prenatal glucocorticoid exposure. This review consolidates diverse findings to help researchers better understand the relationship between the prenatal glucocorticoid overexposure and the effects it has on various fetal brain regions, promoting further development of critical intervention strategies. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of enhancing convection-cooling via active control of the incompressible velocity field, described by a stationary diffusion–convection model. This essentially leads to a bilinear optimal control problem. A rigorous proof of the existence of an optimal control is presented and the first order optimality conditions are derived for solving the control using a variational inequality. Moreover, the second order sufficient conditions are established to characterize the local minimizer. Finally, numerical experiments are conducted utilizing finite elements methods together with nonlinear iterative schemes, to demonstrate and validate the effectiveness of our control design. [ABSTRACT FROM AUTHOR]

The piecewise affine (PWA) model represents an attractive model structure for approximating nonlinear systems. In this paper, a procedure for obtaining the PWA model of the tire nonlinear cornering properties is introduced. In this approach, the highly nonlinear dynamic of the tire cornering properties is well approximated by a set of affine maps which relate inputs and outputs. These maps are defined in disjunctive regions in the regression space, itself composed of system inputs and outputs. The tire cornering properties tests are firstly carried out through a high-performance flat-plate test bench, thus the experimental data which can accurately reflect the tire cornering properties is obtained. On this basis, the PWA identification of the tire cornering properties is composed of the data clustering, the parameter estimation of the affine submodels and the calculation of the hyperplane coefficient matrices, which are respectively achieved by means of fuzzy c-means clustering, weighted least-squares and support vector machines. Finally, to verify the PWA model accuracy in approximating the tire nonlinear cornering properties, the comparison between the simulation results of the PWA identification model and the experimental data is conducted and the comparison results are analyzed. [ABSTRACT FROM AUTHOR]

The properties of pectin extracted from mandarin citrus peels by manosonication extraction (MSp) were systematically studied and compared with pectin obtained by the conventional maceration method (CMp). The yield of MSp (25.5%) was significantly higher than that of CMp (18.3%), while MSp exhibited two Mw fraction distributions. Monosaccharide analysis demonstrated that MSp had more branched RG-I regions (78.3 mol%) than CMp (36.6 mol%) with a high content of arabinose and galactose. The branched-chain morphological characteristics of samples were directly imaged by atomic force microscopy. MSp exhibited a significantly lower degree of methoxylation than CMp by FT-IR and NMR analysis, but X-ray diffraction analysis showed little difference in the level of crystallinity. Moreover, MSp and CMp showed non-Newtonian behaviour, and the increasing order of apparent viscosities was 1.0 w/v% MSp < 1.0 w/v% CMp < 2.0 w/v% CMp < 2.0 w/v% MSp. Thermal analysis and weight loss measurements indicated MSp exhibited greater thermal stability. The results also indicated that both MSp and CMp significantly enhanced the emulsion activity at high concentrations; the emulsions containing 1.5 w/v% pectin showed no phase separation over 21 days, suggesting that MSp could be a potential effective stabiliser in the food and beverage industry. [Display omitted] • The various molecular structures of pectin result in different properties. • MSp possessed more branched RG-I regions with high content of Ara and Gal. • Atomic force microscopy revealed the branched-chain morphology of pectin samples. • MSp showed significantly lower degree of methoxylation via FT-IR and NMR analysis. • MSp revealed better thermal stability and higher viscosity. [ABSTRACT FROM AUTHOR]

Radiative cooling (RC) technology has been widely applied to reduce energy consumption. Nonetheless, in outdoor conditions, radiative coolers gradually lose their radiative cooling performance owing to the accumulation of dust on their surfaces. Here, we propose a simple method based on the tricyclodecane dimethanol diacrylate (DCPDA) monomer. A simple method of UV photografting polymerization modification is presented for preparing a superhydrophobic transparent radiative cooling composite film (STRC film). The prepared film exhibits a high transparency with a maximum transmission of 80 % in the visible wavelength range (400–800 nm), and its average mid-infrared (8–13 μm) emissivity can reach 95 %. The results of the outdoor test show that the temperature of an aluminum plate coated with film decreases by ∼15.5 °C compared to that of a bare aluminum plate when the average irradiance is 782.7 W/m2, indicating that the film possesses excellent radiative cooling properties. The film also has a good superhydrophobicity with a water contact angle (WCA) of 155.5°, which endows the film with a good self-cleaning function. Moreover, the film still exhibits good superhydrophobicity and radiative cooling properties after 45 days of UV irradiation and 7 days of acid/alkaline immersion, demonstrating the film has good durability. • ►A simple method of is presented for preparing a self-cleaning transparent radiative cooling composite film. • ►Self-cleaning transparent radiative cooling composite film a passive cooling technique that consumes zero energy. • ►A novel approach to combining transparent materials, superhydrophobic materials, and radiative cooling technology. [ABSTRACT FROM AUTHOR]

In this paper, we apply the circle method to study the average behavior of the triple divisor function over values of quadratic form n 1 2 + n 2 2 + ⋯ + n l 2 with l ⩾ 3. We improve and generalize previous results. [ABSTRACT FROM AUTHOR]

Purpose. GWAS has successfully located and analyzed the pathogenic genes of osteoporosis. Genetic studies have found that heritability of BMD is 50%–85% while the other half is caused by hip geometric parameters and tissue horizontal characteristics. This study was designed to study the GWAS of osteoporosis in Shanghai Han population. Methods. We collected 1224 unrelated healthy young men (20–40 years old), young women (20–40 years old), and postmenopausal women (over 50 years old) who lived in Shanghai. BMD and hip geometric parameters were measured by dual-energy X-ray absorptiometry. The genomic DNA of peripheral blood was extracted and analyzed by using Illumina Human Asian Screening Array-24 + v 1.0 (ASA) gene chip. Statistical analysis was carried out to evaluate the relationship between these SNPs and BMD and hip geometric parameters. Results. A total of 1155 subjects were included. We found that one SNP rs35282355 located in the human immunodeficiency virus type 1 enhancer-binding protein 3 gene (HIVEP3) and another 25 SNPs located in LINC RNA were significantly correlated with bone mineral content (BMC) in the femoral neck (P = 2.30 × 10−9, P < 5 × 10−8). We also found that the correlation between SNP rs35282355 and cross-sectional area (CSA) of hip geometry was a significant marginal statistical difference (P = 5.95 × 10−8). Conclusions. Through this study, we found that HIVEP3 gene and LINC RNA are potentially correlated with femoral neck BMC. These results provide important information for us to further understand the etiology and genetic pathogenesis of osteoporosis. In the future, we will expand the sample size to verify these loci and carry out molecular research. [ABSTRACT FROM AUTHOR]

Background: Tumor cell-derived exosomes (TEXs) have been widely used to induce antitumor immune responses in animal models and clinical trials. Similarly, leukemia cell-derived exosomes (LEXs) can induce antileukemia immune responses in animal models. However, the antileukemia immunity induced by LEXs is less effective, which may be due to an inadequate costimulatory capacity. Methods: In this study, we transduced L1210 leukemia cells with a lentiviral vector encoding two B7 costimulatory molecules (CD80, CD86) and obtained LEXs that highly expressed CD80 and CD86. The antileukemia immune response derived from these LEXs was examined in vitro and in vivo in animal models. Results: We found that B7 gene-modified LEXs, including LEX-CD80, LEX-CD86, and LEX-8086, could significantly boost the expression of CD80 and CD86 in dendritic cells (DCs) and promote the secretion of functional cytokines such as TNF-α and IL-12. Moreover, these B7 gene-modified LEXs, particularly LEX-CD8086, could effectively induce CD4+ T cell proliferation, Th1 cytokine secretion, and an antigen-specific anti-leukemia cytotoxic T lymphocyte (CTL) response. Additional animal studies indicated that immunization with B7 gene-modified LEXs, in particular LEX-CD8086, could significantly retard tumor growth compared to the control LEXnull group. Conclusions: This study sheds light on the feasibility of obtaining LEXs that overexpress costimulatory molecules via genetically modified leukemia cells, thereby enhancing their anti-leukemia immunity and providing a potential therapeutic strategy that contributes to leukemia immunotherapy. [ABSTRACT FROM AUTHOR]

We consider an approximating control design for optimal mixing of a non-dissipative scalar field θ in an unsteady Stokes flow. The objective of our approach is to achieve optimal mixing at a given final time T > 0 , via the active control of the flow velocity v through boundary inputs. Due to zero diffusivity of the scalar field θ , establishing the well-posedness of its Gâteaux derivative requires sup t ∈ [ 0 , T ] ‖ ∇ θ ‖ L 2 < ∞ , which in turn demands the flow velocity field to satisfy the condition ∫ 0 T ‖ ∇ v ‖ L ∞ (Ω) d t < ∞ . This condition results in the need to penalize the time derivative of the boundary control in the cost functional. Consequently, the optimality system becomes difficult to solve (Hu in Appl Math Optim 78(1):201–217, 2018). Our current approximating approach provides a more transparent optimality system, with the set of admissible controls square integrable in space-time. This is achieved by first introducing a small diffusivity to the scalar equation and then establishing a rigorous analysis of convergence of the approximating control problem to the original one as the diffusivity approaches to zero. Uniqueness of the optimal solution is obtained for the two dimensional case. [ABSTRACT FROM AUTHOR]

The Littlewood–Paley decomposition for functions defined on the whole space ℝ d and related Besov space techniques have become indispensable tools in the study of many partial differential equations (PDEs) with ℝ d as the spatial domain. This paper intends to develop parallel tools for the periodic domain 𝕋 d . Taking advantage of the boundedness and convergence theory on the square-cutoff Fourier partial sum, we define the Littlewood–Paley decomposition for periodic functions via the square cutoff. We remark that the Littlewood–Paley projections defined via the circular cutoff in 𝕋 d with d > 1 in the literature do not behave well on the Lebesgue space L q except for q = 2. We develop a complete set of tools associated with this decomposition, which would be very useful in the study of PDEs defined on 𝕋 d . As an application of the tools developed here, we study the periodic weak solutions of the d -dimensional Boussinesq equations with the fractional dissipation (− Δ) α u and without thermal diffusion. We obtain two main results. The first assesses the global existence of L 2 -weak solutions for any α > 0 and the existence and uniqueness of the L 2 -weak solutions when α ≥ 1 2 + d 4 for d ≥ 2. The second establishes the zero thermal diffusion limit with an explicit convergence rate. [ABSTRACT FROM AUTHOR]

A dual-wavelength laser operating at 912 nm/1030 nm for the first time using a compact intracavity cascade pumping structure is set up The laser system model was designed and built for testing. The proposed system employs a coaxial linear cavity structure and uses a fiber-coupled 808 nm laser diode (LD) end-pumped Nd:GdVO 4 crystal to obtain a 912 nm laser, which then pumped Yb:YAG crystal directly in the cavity to produce a 1030 nm laser. When the LD pump power at 808 nm is 25 W, a 0.97 W laser at 912 nm and a 1.33 W laser at 1030 nm are obtained, respectively. The corresponding optical to optical conversion efficiency is 9.2%. The beam quality factors M2 of 912 nm and 1030 nm lasers at maximum output power is measured to be 1.19 and 1.23. [ABSTRACT FROM AUTHOR]

• An approximating control is addressed for optimal mixing via fluid flows. • Passive and active scalars governed by the transport equation will be discussed. • Navier slip boundary control is employed with low regularity. • Sobolev norm for (H 1 (Ω)) ′ is adopted for quantifying mixing. • Uniqueness of the optimal solution is obtained. The present work focuses on an approximating control design for optimal mixing of a non-dissipative scalar via Navier-Stokes flows in an open bounded and connected domain Ω ⊂ R 2. The objective is to achieve optimal mixing at a given final time T > 0 , via the active control of the flow velocity through the Navier slip boundary control, where Sobolev norm for the dual space (H 1 (Ω)) ′ of H 1 (Ω) is adopted for quantifying mixing. Both passive and active scalars governed by the transport equation will be investigated. Our current approach will lead to a more transparent optimality system for characterizing the optimal solution compared to our previous work [12]. This is achieved by first introducing a small diffusivity to the transport equation and then establishing a rigorous analysis of convergence of the approximating control problem to the original one as the diffusivity converges to zero. Moreover, uniqueness of the optimal solution is obtained. [ABSTRACT FROM AUTHOR]

Hu, W.W., 2019. Impacts of human activities in the Hanjiang River Basin, China. In: Yu, T.-s. (ed.), Environmental Sustainability: Water Resources Integrated Management and the Development of Coastal Environments. Journal of Coastal Research, Special Issue No. 96, pp.68 –75. Coconut Creek (Florida), ISSN 0749-0208. The eastern part of China has a large number of rivers. Humans have a long history of development of rivers, and human activities have a strong impact on rivers. The major impacts are the construction of reservoir dams and river sand excavation. In this study, the Hanjiang River located in the southeast of China's Guangdong Province was chosen as a representative site to study the effects of dams and sand mining on rivers. For dams, the main research is on the impact of dams on the river flow and sediment processes. A comparative analysis of long-term sequence hydrological data before and after the dam construction at the Chaoan Hydrometric Station indicates that dams have a significant effect on sediment reduction. Based on the analysis of the annual average water level data of the long-term sequence at the Liuhuang hydrological station, the multi-year average water level in the middle river decreased by 1.91 m mainly because of the sand mining. The results of the studies on river sand mining have shown that excessive sand mining caused serious downcuts and water level drop in the middle and lower Hanjiang River, especially in the lower river. Dams and river sand mining will change the water and sand balance of the river, affecting the stability of the river course and river regime. These results can be used as a reference for scientific and rational water conservancy project construction, ecological restoration and protection, rational development, and management decisions for rivers in eastern China. [ABSTRACT FROM AUTHOR]

Few studies of childhood poverty in China have considered social deprivations, and fewer still have considered deprivations in contexts beyond the household. In this article, the authors propose a multi-context poverty measure that includes economic and social deprivations in the family, school, and community domains. The authors compare this measure to standard money-metric measures of poverty using a 15-year longitudinal study of children from 100 villages in Northwest China. Nearly a quarter of multi-context poor children are not income poor, while almost three-fourths of the income poor are not multi-context poor. Social and community deprivations are only weakly associated with 'money-metric' deprivations but are significantly linked with short and long-term welfare outcomes for children. The multi-context approach can be tailored to index household and community poverty alleviation targets. [ABSTRACT FROM AUTHOR]

The SPRY domain-containing SOCS box proteins SPSB1, SPSB2, and SPSB4 utilize their SPRY/B30.2 domain to interact with a short region in the N-terminus of inducible nitric oxide synthase (iNOS), and recruit an E3 ubiquitin ligase complex to polyubiquitinate iNOS, resulting in the proteasomal degradation of iNOS. Inhibitors that can disrupt the endogenous SPSB-iNOS interactions could be used to augment cellular NO production, and may have antimicrobial and anticancer activities. We previously reported the rational design of a cyclic peptide inhibitor, cR8, cyclo(RGDINNNV), which bound to SPSB2 with moderate affinity. We, therefore, sought to develop SPSB inhibitors with higher affinity. Here, we show that cyclic peptides cR7, cyclo(RGDINNN), and cR9, cyclo(RGDINNNVE), have ~6.5-fold and ~2-fold, respectively, higher SPSB2-bindng affinities than cR8. We determined high-resolution crystal structures of the SPSB2-cR7 and SPSB2-cR9 complexes, which enabled a good understanding of the structure–activity relationships for these cyclic peptide inhibitors. Moreover, we show that these cyclic peptides displace full-length iNOS from SPSB2, SPSB1, and SPSB4, and that their inhibitory potencies correlate well with their SPSB2-binding affinities. The strongest inhibition was observed for cR7 against all three iNOS-binding SPSB proteins. [ABSTRACT FROM AUTHOR]

This work develops an efficient and accurate optimization algorithm to study the optimal mixing problem driven by boundary control of unsteady Stokes flows, based on the theoretical foundation laid by Hu and Wu in a series of work. The scalar being mixed is purely advected by the flow and the control is a force exerted tangentially on the domain boundary through the Navier slip conditions. The control design has potential applications in many industrial processes such as rotating wall driven mixing, mircomixers with acoustic waves, and artificial cilia mixing. The numerical algorithms have high complexity, high accuracy demand, and high computing expense, due to the multiscale nature of the mixing problem and the optimization requirements. A crucial problem is the computation of the Gâteaux derivative of the cost functional. To this end, a hybrid approach based on variational formula and finite difference is built with high accuracy and efficiency to treat various types of control input functions. We have experimented with various optimization algorithms including the steepest descent algorithm, the conjugate gradient method and two line search options (backtracking and exact line search). We are able to identify and implement the best combinations. The numerical simulations show that the mixing efficacy is limited when only one single type of control is applied, but can be enhanced when more diverse control types and more time segmentation are utilized. The mix-norm in the optimal mixings decays exponentially. The numerical study in this work demonstrates that boundary control alone could be an effective strategy for mixing in incompressible flows. • First numerical study of optimal control for advective mixing via boundary force in Stokes flow. • Wide applications in rotating wall mixing, mircomixers, and artificial cilia mixing. • Numerical methods have high complexity, high accuracy demand, and high computing expense. • New techniques: a hybrid method of cost derivative, and a mesh-relay algorithm of search. • Boundary mixing results can be comparable to those of internal mixing with exponential decay. [ABSTRACT FROM AUTHOR]

Highlights • BDNF promoted the release of Ach from cholinergic-like neurons. • BDNF modified hUC-MSCs-derived cholinergic-like neurons improved spatial learning and memory abilities in AD rats. Abstract Alzheimer's disease (AD) is an age-related neurodegenerative disease and the most common type of dementia. Although it is still incurable, stem cell replacement therapy provides new hope for AD. Human umbilical cord mesenchymal stem cells (hUC-MSCs) have multiple differentiation potentials, which can differentiate into cholinergic-like neurons and promote the release of acetylcholine. Brain-derived neurotrophic factor (BDNF) can also promote neurogenesis and synaptic formation, reduce oxidative stress and cell death. Therefore, we investigated the therapeutic effects of BDNF modified hUC-MSCs-derived cholinergic-like neurons in AD rats in this study. To make AD models, 1 μl beta amyloid (Aβ) 1-42 was injected into the right hippocampus of the rats. After two weeks, the hUC-MSCs-derived cholinergic-like neurons null cells or overexpressing BDNF cells delivered by lentiviral vectors were slowly injected into the right hippocampus of the AD rats. After 8 weeks of transplantation, Morris water maze test, Western blotting, Immunohistochemistry, Immunofluorescence assay and TdT mediated dUTP Nick End Labeling (TUNEL) detection were performed. Transplantation of BDNF modified hUC-MSCs-derived cholinergic-like neurons significantly improved spatial learning and memory abilities in the AD rats, increased the release of acetylcholine and ChAT expression in the hippocampus, enhanced the activation of astrocytes and microglia, reduced the expression of Aβ and recombinant human beta-site APP-cleaving enzyme1 (BACE1), inhibited neuronal apoptosis, and promoted neurogenesis. Our results demonstrate that BDNF modified hUC-MSCs-derived cholinergic-like neurons might be a promising therapeutic strategy for AD. [ABSTRACT FROM AUTHOR]

Abstract A intracavity cascading pumped dual-wavelength output Nd:YAG/Yb:YAG laser is demonstrated for the first time. The system adopts a coaxial composite cavity structure, and using an all-solid-state Nd:YAG laser operating at 946 nm as intracavity pump source, a 1160 mW 946 nm laser and a 43 mW 1030 nm laser were obtained with 1.39 W absorbed pump power. The fluctuation of the output power was better than 5% in the given 30 min. The corresponding beam quality factors M2 are 1.25 and 1.27. [ABSTRACT FROM AUTHOR]

A new set of tetraethylene glycol tethered ciprofloxacin–isatin hybrids 5a–l with greater lipophilicity than the parent ciprofloxacin was designed, synthesized, and screened for their in vitro antimycobacterial activity against drug‐sensitive Mycobacterium tuberculosis (MTB) H37Rv and multidrug‐resistant MTB strains as well as toxicity in a mammalian VERO cell line. The preliminary results revealed that all hybrids exhibited considerable activity against MTB H37Rv with minimum inhibitory concentration in a range of 0.205–14.186 μg/mL. Especially, hybrid 5a with low cytotoxicity displayed highest activity against both drug‐sensitive MTB H37Rv and two clinically isolates multidrug‐resistant MTB strains, suggesting that it may serve as a new and promising candidate for further study. [ABSTRACT FROM AUTHOR]

We propose a hybridizable discontinuous Galerkin (HDG) method to approximate the solution of a distributed optimal control problem governed by an elliptic linear convection diffusion PDE. We use degree k polynomials to approximate the state, adjoint state, their fluxes, and the optimal control, and we show the approximations converge with order k + 1 in the L 2 norm. Finally, we use a simple element-by-element postprocessing scheme to obtain new superconvergent approximations of the state, dual state and the control. We show the postprocessed variables converge with order k + 2 in the L 2 norm. We present 2D and 3D numerical experiments to illustrate our theoretical results. [ABSTRACT FROM AUTHOR]

We discuss the problem of suppression of singularity via flow advection in chemotaxis modeled by the Patlak–Keller–Segel (PKS) equations. It is well-known that for the system without advection, singularity of the solution may develop at finite time. Specifically, if the initial condition is above certain critical threshold, the solution may blow up in finite time by concentrating positive mass at a single point. In this work, we mainly focus on the global regularity and stability analysis of the PKS system in the presence of flow advection in a bounded domain Ω ⊂ R d , d = 2 , 3 , by using a semigroup approach. We will show that the global well-posedness can be obtained as long as the semigroup generated by the associated advection–diffusion operator has a rapid decay property. We will also show that for cellular flows in rectangle-like domains, such property can be achieved by rescaling both the cell size and the flow amplitude. This is analogous to the result established by Iyer, Xu and Zlatoš (2021) on the torus T d , d = 2 , 3. [ABSTRACT FROM AUTHOR]

Transmissible gastroenteritis virus (TGEV) causes severe diarrhea and high mortality in newborn piglets. It is well established that porcine intestinal epithelium is the target of the TGEV infection, however the mechanism that TGEV invades the host epithelium remains largely unknown. Aminopeptidase N (APN) is a known receptor of TGEV. This study discovered that the extracellular receptor binding domain 1 pertaining to epidermal growth receptor (EGFR) interact with TGEV spike protein. APN and EGFR synergistically promote TGEV invasion. TGEV promotes APN and EGFR clustering early in infection. Furthermore APN and EGFR synergistically stimulate PI3K/AKT as well as MEK/ERK1/2 endocytosis signaling pathways. TGEV entry is via clathrin and caveolin mediated endocytosis in IPEC-J2 cells. TGEV binds with EGFR, and subsequently promotes EGFR internalization by a clathrin-mediated endocytosis pathway. These results show that EGFR is a co-factor of TGEV, and that it plays a synergistic role with APN early in TGEV infection. [ABSTRACT FROM AUTHOR]

We discuss the optimal boundary control problem for mixing an inhomogeneous distribution of a passive scalar field in an unsteady Stokes flow. The problem is motivated by mixing the fluids within a cavity or vessel at low Reynolds numbers by moving the walls or stirring at the boundary. It is natural to consider the velocity field which is induced by a control input tangentially acting on the boundary of the domain through the Navier slip boundary conditions. Our main objective is to design an optimal Navier slip boundary control that optimizes mixing at a given final time. This essentially leads to a finite time optimal control problem of a bilinear system. In the current work, we consider a general open bounded and connected domain Ω⊂Rd,d=2,3. We employ the Sobolev norm for the dual space (H1(Ω))′ of H1(Ω) to quantify mixing of the scalar field in terms of the property of weak convergence. A rigorous proof of the existence of an optimal control is presented and the first-order necessary conditions for optimality are derived. [ABSTRACT FROM AUTHOR]

The Aerosol Mass Spectrometer (AMS) and Aerosol Chemical Speciation Monitor (ACSM) are widely used for quantifying submicron aerosol mass concentration and composition, in particular for organic aerosols (OA). Using the standard vaporizer (SV) installed in almost all commercial instruments, a collection efficiency (CE) correction, varying with aerosol phase and chemical composition, is needed to account for particle bounce losses. Recently, a new “capture vaporizer” (CV) has been shown to achieve CE∼1 for ambient aerosols, but its chemical detection properties show some differences from the SV due to the increased residence time of particles and vaporized molecules inside the CV. This study reports on the properties and changes of mass spectra of OA in CV-AMS using both AMS and ACSM for the first time. Compared with SV spectra, larger molecular-weight fragments tend to shift toward smaller ions in the CV due to additional thermal decomposition arising from increased residence time and hot surface collisions. Artifact CO+ ions (and to a lesser extent, H2O+), when sampling long chain alkane/alkene-like OA (e.g., squalene) in the CV during the laboratory studies, are observed, probably caused by chemical reactions between sampled OA and molybdenum oxides on the vaporizer surfaces (with the carbon derived from the incident OA). No evidence for such CO+ enhancement is observed for ambient OA. Tracer ion marker fractions (fm/z =, i.e., the ratio of the organic signal at a given m/z to the total OA signal), which are used to characterize the impact of different sources are still present and usable in the CV. A public, web-based spectral database for mass spectra from CV-AMS has been established. Copyright © 2018 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Several Pt(IV) prodrugs containing SAA, a histone deacetylases inhibitor, were designed and prepared for multiply targeting genomic DNA, histone deacetylases and PARP-1. The resulting Pt(IV) prodrug had significantly strong antiproliferative activity against the tested cancer cell lines, especially SAA1, derived from the conjugation of cisplatin and SAA, had potent ability to overcome cisplatin resistance. Under the combined action of DNA platination and inhibition of HDACs and PARP-1 activity, the cytotoxic activity of SAA1 was 174-fold higher than cisplatin against cisplatin-resistant SGC7901/CDDP cancer cells. The mechanism of action of SAA1 was preliminarily investigated, in which cellular uptake, cell apoptosis and cell cycle arrest as well as western blot analysis were made by treating SAA1 with SGC7901/CDDP cells. Besides, HDACs inhibition activity and PARP-1 enzyme inhibition of SAA1 were also studied. [ABSTRACT FROM AUTHOR]

A Pt(IV) prodrug ( 2 ) composed of cancer-targeting biotin and nonsteroidal anti-inflammatory drug indomethacin in the axial positions of the six-coordinated octahedral geometry derived from cisplatin was developed, which could be highly accumulated in cancer cells more than normal ones and activated by endogenous reducing molecules to release cisplatin and indomethacin moieties simultaneously to inhibit tumor progression synergistically. In vitro assays revealed that 2 exhibited significantly selective inhibition to the tested cancer cell lines and sensitivity to cisplatin resistant cancer cells. Moreover, 2 presented cyclooxygenases inhibition properties to reduce tumor-associated inflammation, reduced the invasiveness of the highly aggressive PC-3 cells, and disrupted capillary-like tube formation in EA.hy926 cells. In all, this study offers a new strategy to enhance sensitivity and reduce toxicity of cisplatin. [ABSTRACT FROM AUTHOR]

The degree of hydrolysis is one of the most important indexes for process control and quality assessment in proteins enzymatic hydrolysis. This article proposed a simple and rapid near infrared spectroscopy method for real-time quantifying the degree of hydrolysis in alcalase hydrolysis process. Efficient variables selection algorithms were systemically studied in multivariate calibrations; the partial least squares coupled with uninformative variables elimination and ant colony optimization were proposed for modeling with results yieldingRp= 0.9525. Additionally, 10 independent samples with the relative error less than 10% further confirmed the stability and reliability of this method. This work demonstrated that the near infrared spectroscopy technique with a selected multivariate calibration has a high potential forin situmonitoring of alcalase hydrolysis process in protein industry. [ABSTRACT FROM AUTHOR]

The neurotransmitter histamine receives less attention compared with other biogenic amines, because of its moderate action in the central nervous system (CNS). However, recent evidence suggests that histamine plays an important role in multiple CNS disorders including insomnia, narcolepsy, Parkinson's diseases, schizophrenia, Alzheimer's disease, and cerebral ischemia. New insights are emerging into the potential roles of histamine receptors as targets for the treatment of these diseases. Although some histamine related agents have failed in clinical trials, current preclinical studies suggest that this neurotransmitter may still have extensive applications in treating CNS disorders, however, advanced studies are warranted. This review summarizes findings from animal models and clinical research on the role of histamine and its receptor ligands in the brain for treatment of CNS disorders. The development of novel histamine receptor ligands and gaining an in-depth understanding of their potential mechanisms are necessary stepping stones to unlock their wide-ranging applications in the clinical arena. [ABSTRACT FROM AUTHOR]

The aerosol mass spectrometer (AMS) and aerosol chemical speciation monitor (ACSM) are widely used for quantifying aerosol composition. The quantification uncertainty of these instruments is dominated by the collection efficiency (CE) due to particle bounce. A new “capture vaporizer” (CV) has been recently developed to achieve unit CE. In this study, we examine the performance of the CV while sampling ambient aerosols. AMS/ACSMs using the original standard vaporizer (SV) and CV were operated in parallel during three field studies. Concentrations measured with the CV (assuming CE = 1) and SV (using the composition-dependent CE of Middlebrook et al.), as well as SMPS and PILS-IC are compared. Agreement is good in all cases, verifying that CE ∼ 1 in the CV when sampling ambient particles. Specific findings include: (a) The fragmentation pattern of ambient nitrate and sulfate species observed with the CV was shifted to smallerm/z, suggesting additional thermal decomposition. (b) The differences in fragmentation patterns of organic vs. inorganic nitrate and sulfur species are still distinguishable in the CV, however, with much lower signal-to-noise compared to the SV. (c) Size distribution broadening is significant, but its impact is limited in field studies since ambient distributions are typically quite broad. Consistent size distributions were measured with the SV and CV. (d) In biogenic areas, UMR nitrate is overestimated based on the default fragmentation table (∼factor of 2–3 in SOAS) for both vaporizers, due to underestimation of the organic interferences. We also report a new type of small interference: artifact chloride signal can be observed in the AMS when high nitrate mass concentration is sampled with both the SV (∼0.5% chloride/nitrate) or CV (∼0.2% chloride/nitrate). Our results support the improved quantification with the CV AMS and characterize its chemical detection properties. Copyright © 2017 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Mycoplasma hyopneumoniae ( Mhp ) is the primary etiological agent responsible for swine enzootic pneumonia (EP), a disease that cause tremendous economic losses all over the swine industry. Dendritic cells (DCs), the most effective antigen-presenting cells, are widely distributed beneath respiratory epithelium. DCs uptake and present antigens to T cells, to initiate protective immune responses or generate immune-mediated pathology in different infections. In this study, we investigated the changes in the different DCs subpopulations, T cells and SIgA positive cells counts in porcine nasal cavity after long time Mhp infection. We further evaluated the role of porcine DCs in Mhp exposure. Our results showed that the number of SLA-II-DR + SWC3a + DCs, SLA-II-DR + CD11b + DCs, T cells, SIgA positive cells in nasal cavity were decreased after Mhp 28 days infection in vivo experiment. The antigen presenting ability of DCs were inhibited by Mhp exposure. DCs couldn’t activate T-cell proliferation by down-regulating the antigen presenting molecule CD1a expression and promoting high level of IL-10 production. Further more, the expression levels of IL-12 and IFN-γ in DCs were decreased, suggesting that DCs favour for Th2 immune response development after Mhp exposure in vitro. Taken together, Mhp infection impairs the immune function which allows the persistence of Mhp and cause predispose pigs to secondary infections. The decline of DCs presentation ability is the reason why dysfunction and persistence in Mhp infection. These findings are benefit for exploring the pathogenic mechanisms of Mhp in pigs. [ABSTRACT FROM AUTHOR]

We consider the problem of the optimal shape of a two dimensional duct which contains a fluid governed by the Stokes equations with mixed boundary conditions. The conduit domain is assumed to be non-smooth and perturbations are allowed only on the walls, while the objective functional aims at minimizing the head loss and to enforce a uniform velocity profile at the outlet. We show existence of solutions to the shape optimization problem and determine the existence of the shape derivative. [ABSTRACT FROM AUTHOR]

The rhamnogalacturonan I (RG-I) region of pectin shows health benefits and novel gel applications. Commercial pectin is extracted from citrus peel in most instances, whereas they are homogalacturonan (HG)-dominated productions and the methods to extract pectin targeting RG-I are limited. To take full advantage of citrus wastes and upgrading this pectin resources, a new extraction method based on a diluted NaOH assisted by a combination of ultrasound (US) and pressure, namely manosonication (MS), was established for RG-I enriched pectin extraction. MS significantly enhanced the pectin yield (21.47 ± 0.11%) while reducing the use of NaOH reagents (50 mmol/L) and processing time (50 min). Structurally, the MS (300 kPa) resulting products achieved nearly a 2-fold greater RG-I content (58.61 mol%) than that of commercial pectin (30.12 mol%). Moreover, for the investigation of the extraction mechanism, external pressure enhanced the cavitation effect, as the calorimetric intensity increased from 1.28 W/mL (100 kPa) to 3.3 W/mL (350 kPa). A sufficient ultrasonic mechanical action allowed for obtaining RG-I enriched products with large molecular weight (9.506 × 104–2.813 × 105) and low degree of methoxylation. Transmission electron microscopy (TEM) and scanning electron microscopies (SEM) verified the increased disintegration of the cell wall tissue by MS. Raman imaging and immunofluorescence labeling suggested the synergistic effect of pressure and ultrasound on enhancing the yields and RG-I content. This new method provided alternations in functional polysaccharides extraction, and the yield and structure of citrus RG-I enriched pectin strongly indicates the potentials of MS in other RG-I rich vegetables applications. [Display omitted] • Chemical compositions of extracted pectin between different methods were compared. • Manosonication extraction improved pectin yield and RG-I region content. • External pressure enhanced the ultrasonic cavitation effect. • Mechanical action was the dominating factor in cellulose network destruction. • Immunolabeling suggested the synergistic extraction mechanism on RG-I dissolution. [ABSTRACT FROM AUTHOR]

Rare earth-doped upconversion nanoparticles (UCNPs) have promising potentials in biodetection due to their unique frequency upconverting capability and high detection sensitivity. This paper reports an improved UCNPs-based fluorescence probe for dual-sensing of Aflatoxin B1 (AFB1) and Deoxynivalenol (DON) using a magnetism-induced separation and the specific formation of antibody-targets complex. Herein, the improved UCNPs, which were namely NaYF 4 :Yb/Ho/Gd and NaYF 4 :Yb/Tm/Gd, were systematically studied based on the optimization of reaction time, temperature and the concentration of dopant ions with simultaneous phase and size controlled NaYF 4 nanoparticles; and the targets were detected using the pattern of competitive combination assay. Under an optimized condition, the advanced fluorescent probes revealed stronger fluorescent properties, broader biological applications and better storage stabilities compared to traditional UCNPs-based ones; and ultrasensitive determinations of AFB1 and DON were achieved under a wide sensing range of 0.001–0.1 ng ml −1 with the limit of detection (LOD) of 0.001 ng ml −1 . Additionally, the applicability of the improved nanosensor for the detection of mycotoxins was also confirmed in adulterated oil samples. [ABSTRACT FROM AUTHOR]

Rare earth-doped upconversion nanoparticles have promising potential in the field of pesticide detection because of their unique frequency upconverting capability and high detection sensitivity. This paper reports a novel aptamer-based nanosensor for acetamiprid detection using fluorescence resonance energy transfer (FRET) between NH 2 -NaYF 4 : Yb, Ho@SiO 2 (UCNPs) and gold nanoparticles (GNPs). Herein, GNPs as acceptors efficiently quench the fluorescence of UCNPs and acetamiprid specifically interacts with acetamiprid binding aptamer (ABA), causing the conformation changes of ABA from random coil to hairpin structure. Accordingly, ABA no longer stabilizes the GNPs in salt solution, leading to the varying aggregation extent of GNPs. Thus, the fluorescence of UCNPs are proportionally recovered. Under the optimized conditions, the enhancement efficiency was observed to increase linearly with the concentration of acetamiprid from 50 nM to 1000 nM, resulting in a relatively low limit of 3.2 nM. Additionally, the aptasensor demonstrated high selectivity to similar structure pesticides such as imidacloprid and chlorpyrifos, and further confirmed its application capacity in adulterated tea samples. [ABSTRACT FROM AUTHOR]

Four platinum(II) complexes,trans-[bicyclo[2.2.2]octane-7R,8R-diamine]bis(alkoxyacetato-O,O’) platinum(II) (alkoxyacetate = methoxyacetate (2), ethoxyacetate (3), isopropoxyacetate (4), andtert-butoxyacetate (5)) were synthesized and spectrally characterized. The cytotoxicity of these water-soluble complexes was evaluated by CCK-8 assayin vitroagainst HCT-116, HepG-2, and A549 cancer cell lines. Most of the complexes had cytotoxic activity against the tested cancer cell lines. Among them,3showed more potent antitumor effect than cisplatin or oxaliplatin. Complex3could cause HCT-116 cell line death based on an apoptotic pathway since it has a dicyclic moiety similar to 1R,2R-diaminocyclohexane in oxaliplatin. Agarose gel electrophoresis on the interaction between3and DNA indicated that it has different behavior from that of cisplatin or oxaliplatin, which has a high correlation with the ligand used. [ABSTRACT FROM PUBLISHER]