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Ministry of Science and Technology of China (grant nos. 2019YFE0124200 and 2018YFE0100800), National Natural Science Foundation of China (grant no. 61874075), Baseline funding scheme of the King Abdullah University of Science and Technology

Linear local tangent space alignment (LLTSA) is a classical dimensionality reduction method based on manifold. However, LLTSA and all its variants only consider the one-way mapping from high-dimensional space to low-dimensional space. The projected low-dimensional data may not accurately and effectively “represent” the original samples. This paper proposes a novel LLTSA method based on the linear autoencoder called LLTSA-AE (LLTSA with Autoencoder). The proposed LLTSA-AE is divided into two stages. The conventional process of LLTSA is viewed as the encoding stage, and the additional and important decoding stage is used to reconstruct the original data. Thus, LLTSA-AE makes the low-dimensional embedding data “represent” the original data more accurately and effectively. LLTSA-AE gets the recognition rates of 85.10, 67.45, 75.40 and 86.67% on handwritten Alphadigits, FERET, Georgia Tech. and Yale datasets, which are 9.4, 14.03, 7.35 and 12.39% higher than that of the original LLTSA respectively. Compared with some improved methods of LLTSA, it also obtains better performance. For example, on Handwritten Alphadigits dataset, compared with ALLTSA, OLLTSA, PLLTSA and WLLTSA, the recognition rates of LLTSA-AE are improved by 4.77, 3.96, 7.8 and 8.6% respectively. It shows that LLTSA-AE is an effective dimensionality reduction method.

Spintronics-based microwave devices, such as oscillators and detectors, have been the subject of intensive investigation in recent years owing to the potential reductions in size and power consumption. However, only a few concepts for spintronic amplifiers have been proposed, typically requiring complex device configurations or material stacks. Here, we demonstrate a spintronic amplifier based on two-terminal magnetic tunnel junctions (MTJs) produced with CMOS-compatible material stacks that have already been used for spin-transfer torque memories. We achieve a record gain (|S11 | > 2) for input power on the order of nW (

Recent studies have shown a correlation between high-density lipoprotein cholesterol (HDL-C) and bone mineral density (BMD) in adults, but their relationship is unclear in adolescents. This study aimed to explore whether a correlation existed between them among adolescents aged 12–19. Data analyzed in our study was fetched from the National Health and Nutrition Examination Survey (NHANES) database 2011–2018. The relationship between HDL-C level and total BMD value was analyzed by multivariate logistic regression models, fitted smoothing curves, and generalized additive models. 3770 participants participated in this analysis. After adjusting for all relevant covariates involved in this study, we found a negative correlation between HDL-C levels and total bone density in male adolescents.Furthermore, the stratified analysis showed that all covariables-adjusted models retained the negative correlation excepting female, black, or Mexican American subgroups. An inverted U-shaped curve represented the correlation of HDL-C and total BMD among adolescents aged 16 to 19, and the turning point was 1.06 mmol/L. After adjusting for all relevant covariates involved in this study, the study found a negative correlation between HDL-C levels and total BMD in male adolescents aged 12 to 19, particularly among those of races other than Black and Mexican. There was a saturation effect between HDL-C level and total BMD in 16–19-year-old adolescents. The turning point was 1.06 mmol/L. Therefore, HDL-C might be a biomarker to detect bone health and further perform a more detailed examination.

Mechanical strain regulated osteoclastic differentiation and angiogenesis are crucial for bone modeling and remodeling, and previous data indicate that high-magnitude strain within physiological load regulates osteoclastic differentiation. However, the underlying mechanisms are still not fully understood. In the present study, the RAW264.7 mouse monocyte/macrophage was used as an osteoclast precursor, and the bone marrow-derived macrophages (BMMs) were isolated and cultured in vitro. The above cells were subjected to macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-kB ligand (RANKL) for the induction of osteoclast differentiation. Subsequently, the above cells were stretched by differential strain magnitudes to simulate the mechanical stimuli in the physiological conditions, and we found that low-magnitude strain (100 με) increased the expression levels of Acp5, Clcn7, MMP9 and Ctsk to promote osteoclastogenesis, while high-magnitude strain (3000 με) had opposite effects. In addition, we noticed that high-magnitude strain upregulated PTEN to inactivate the PI3K/Akt signaling pathway, and silencing of PTEN abrogated the suppressing effects of high-magnitude strain on osteoclastic differentiation. Next, we screened out that high-magnitude strain downregulated miR-21 to promote PTEN expressions in a competing endogenous RNA (ceRNA)-dependent manner. Finally, upregulation of miR-21 recovered osteoclastic differentiation in RAW264.7 and BMMs cells stimulated with high-magnitude strain. Collectively, our findings suggested that high-magnitude mechanical strain affected osteoclastic differentiation through modulating the miR-21/PTEN/PI3K/Akt signaling cascade, which provided potential strategies for the treatment of bone-related diseases. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10616-021-00507-x.

In this article, we study stochastic functional linear models (SFLM) driven by an underlying square integrable stochastic process X(t) which is generated by a standard Brownian motion. Utilizing the magnificent Ito integrals and Malliavin calculus, X(t) is expanded into a summation of orthogonal multiple integrals, i.e., Wiener-Ito chaos expansions, which is the counterpart of the Taylor expansion of deterministic functions. Based on the expansion, we show that the fourth moments of linear functionals of underlying stochastic process X(t) are bounded by the square of their second moments when X(t) is a finite linear combination of multiple Ito integrals. Therefore, an optimal minimax convergence rate in mean prediction risk of SFLM is valid if eigenvalues of related linear operators are of order $$k^{-2r}$$ by using results in literature when the underlying process X(t) is a linear combination of multiple Ito integrals. A sufficient and necessary condition of finite fourth moment of random functions of multiple Ito integrals is proved, which is a key condition in methodology and convergence rates of functional linear regressions. Our results show that the optimal minimax convergence rate in mean prediction risk can be applied to the class of linear combination of multiple Ito integrals which are not necessarily Gaussian processes. Moreover, the sufficient and necessary condition of finite fourth moment for multiple Ito integrals can be directly applied to show methodology and convergence rates of functional linear models. Using the theory of stochastic analysis, one may construct a reproducing kernel Hilbert space (RKHS) associated with a square integrable stochastic process to facilitate analysis of functional data.

In this study, interactive alternate forward extrusion (AFE) experiments with varying number of extrusion passes of AZ31 magnesium alloy were carried out. The evolution of microstructure, and texture and their effects on the mechanical properties were studied. The results show that with the increase of loading passes, the grains are significantly refined, and the dynamic recrystallisation (DRX) structure is uniformly distributed in the product, which is the main reason for the increase in microhardness, compressive strength and failure strain. Further, slip and twinning induced DRX behaviour are considered to be the main deformation methods in the early stage of deformation. Whereas continuous DRX is considered to be the main deformation methods for the change in grain morphology in the later stage. During the extrusion process, the deflection angle of the base pole decreases. Finally, the fibre texture is formed; the texture strength is significantly reduced because of the effect of recrystallisation. The AZ31 magnesium alloy interactive AFE process is discussed with respect to the technological experiment and the microstructure deformation, thus providing a vital scientific basis for further application.

To measure the 24-h intraocular pressure (IOP) by Icare PRO rebound in healthy and primary open-angle glaucoma (POAG) eyes and compare it with non-contact tonometry (NCT). Thirty POAG patients, who were under IOP-lowering treatment, and 30 healthy subjects were included. Participants were hospitalized overnight for the 24-h IOP measurement. IOPs were measured by Icare PRO and NCT according to a standard protocol every 2 h during 24 h. The 24-h IOP curve and IOP-related parameters were compared between Icare PRO and NCT groups in POAG and healthy eyes. The IOPs measured by Icare PRO in habitual position increased notably at 22:00 in the normal group and at 20:00 in the POAG group, reached peak at 0:00, stayed high until 4:00, and then decreased in both groups (all p

In this paper, we propose a multimodal flexible sensory interface for interactively teaching soft robots to perform skilled locomotion using bare human hands. First, we develop a flexible bimodal smart skin (FBSS) based on triboelectric nanogenerator and liquid metal sensing that can perform simultaneous tactile and touchless sensing and distinguish these two modes in real time. With the FBSS, soft robots can react on their own to tactile and touchless stimuli. We then propose a distance control method that enabled humans to teach soft robots movements via bare hand-eye coordination. The results showed that participants can effectively teach a self-reacting soft continuum manipulator complex motions in three-dimensional space through a “shifting sensors and teaching” method within just a few minutes. The soft manipulator can repeat the human-taught motions and replay them at different speeds. Finally, we demonstrate that humans can easily teach the soft manipulator to complete specific tasks such as completing a pen-and-paper maze, taking a throat swab, and crossing a barrier to grasp an object. We envision that this user-friendly, non-programmable teaching method based on flexible multimodal sensory interfaces could broadly expand the domains in which humans interact with and utilize soft robots.

Background Hydrogels loaded with antimicrobial agents have been widely used for treating infected wound defects. However, hydrogels derived from a porcine dermal extracellular matrix (PADM), containing silver nanoparticles (AgNPs), have not yet been studied. Therefore, we investigated the therapeutic effect of an AgNP-impregnated PADM (AgNP–PADM) hydrogel on the treatment of infected wounds. Methods An AgNP–PADM hydrogel was synthesized by embedding AgNPs into a PADM hydrogel. We examined the porosity, moisture retention, degradation, antibacterial properties, cytotoxicity, antioxidant properties, and ability of the PADM and AgNP–PADM hydrogels to treat infected wounds in animals. Results The PADM and AgNP–PADM hydrogels were pH sensitive, which made them flow dynamically and solidify under acidic and neutral conditions, respectively. The hydrogels also exhibited porous network structures, satisfactory moisture retention, and slow degradation. Additionally, the AgNP–PADM hydrogel showed a slow and sustained release of AgNPs for at least 7 days without the particle size changing. Thus, the AgNPs exhibited adequate antibacterial ability, negligible toxicity, and antioxidant properties in vitro. Moreover, the AgNP–PADM hydrogel promoted angiogenesis and healed infected skin defects in vivo. Conclusions The AgNP–PADM hydrogel is a promising bioderived antibacterial material for clinical application to infected wound dressings.

The visual detection of mitochondrial viscosity is of considerable significance in that it is associated with various cellular functions. Herein, a novel red-emitting viscosity probe YD-Mito constructed by linking phenylamine derivatives and benzo[e]indolium through a C–C double bond has been designed and synthesized. It was found that YD-Mito exhibited a special response to viscosity accompanying with a sharp fluorescence enhancement (20-fold) at 620 nm. Importantly, YD-Mito can precisely localized in mitochondria independent from membrane potential and visualized the mitochondrial viscosity. Therefore, probe YD-Mito could provide a powerful tool for the determination of mitochondrial viscosity.

A mixture of Pingdingshan lean coal and acid-treated Huadian oil shale was co-pyrolyzed in a drop-tube fixed-bed reactor in the temperature range of 300 °C–450 °C. To reveal the formation mechanism of the solid co-pyrolysis product, changes in some physico-chemical properties were investigated, using analysis by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, pore analysis, thermogravimetry, and electron spin resonance. X-ray diffraction showed that the lattice plane spacing for the co-pyrolyzed mixture decreased from 0.357 nm to 0.346 nm and the average stacking height increased from 1.509 nm to 1.980 nm in the temperature range of 300 °C–450 °C, suggesting that pyrolysis treatment increased its degree of metamorphism. The amount of oxygen-containing functional groups and pore volume decreased with increasing temperature. Thermogravimetry and electron spin resonance results showed that synergistic effects occurred during the copyrolysis process. A formation mechanism for the solid product was proposed. Hydrogen-rich radicals generated from the pyrolysis of the oil shale were trapped by hydrogen-poor macromolecular radicals of the intermediate metaplast produced from coal pyrolysis, thereby increasing the yield of solid product.

Cancer includes a range of diseases that arise as a result of the unregulated growth of malignant cells, which have the potential to invade or spread to other body parts. Nanoparticles and drug conjugate systems enable unique approaches for cancer treatment. The present study focused on anti-breast cancer activity of rutin-chitosan nanoconjugates in in vitro system. Rutin-chitosan nanoconjugates were prepared by ionic gelation process and characterized by UV–Vis Spectra analysis, DLS, SEM, Zeta potential, FT-IR and XRD analysis. Further the nanoconjugates was evaluated for its anti-cancer activity on Triple Negative Breast Cancer (TNBC), it shows significant activity against selected breast cancer cells. The Inhibitory concentration (IC50) of synthesized nano-conjugate was found to be 12.5 µg/mL. Furthermore, we found noteworthy cell cycle arrest at DNA synthetic phase following apoptotic cell deaths which were evidenced by AO/EtBr and DAPI fluorescence micrographic analysis. Our findings apparently validate that synthesized nano-conjugates could efficiently initiate the apoptotic process in the triple negative breast cancer cells. Through this finding, it is evidenced that the synthesized nanoconjugates potential applications in anti-cancer therapies.

Fine grain modification is an important means for preparing lightweight and low-plasticity materials, including magnesium alloys. This paper proposes an accumulative alternating back extrusion (AABE) technique for preparing magnesium alloy materials. Metallographic microscopy and electron backscatter diffraction were used to test the resulting magnesium alloy samples and indicated that AABE can effectively refine microstructure and improve uniformity in local areas of the sample. After one pass of AABE, the upper part of the specimen was mainly characterized by recrystallization, with a high degree of refinement. The lower part showed coexisting recrystallization refinement and twinning refinement, which are less preferable. The mean grain size after applying five passes of AABE was half that of the samples subjected to only one pass. AABE is a novel and effective method for preparing high-performance magnesium alloy materials.

With the advance of smart material science, robotics is evolving from rigid robots to soft robots. Compared to rigid robots, soft robots can safely interact with the environment, easily navigate in unstructured fields, and be minimized to operate in narrow spaces, owning to the new actuation and sensing technologies developed by the smart materials. In the review, different actuation and sensing technologies based on different smart materials are analyzed and summarized. According to the driving or feedback signals, actuators are categorized into electrically responsive actuators, thermally responsive actuators, magnetically responsive actuators, and photoresponsive actuators; sensors are categorized into resistive sensors, capacitive sensors, magnetic sensors, and optical waveguide sensors. After introducing the principle and several robotic prototypes of some typical materials in each category of the actuators and sensors. The advantages and disadvantages of the actuators and sensors are compared based on the categories, and their potential applications in robotics are also presented.

In this study, on the basis of the various contact angles and the hybrid theory, a new mathematic model without the raceway control hypothesis is proposed for the analysis of ball bearing under the combined axial, radial and moment loads. Instead of the orthogonal decomposition method, the triangular geometric theorem and vector diagram method have been used in the force analysis of local ball to improve the computation efficiency of bearing analysis. For validation purpose, the comparative analysis of the ball-raceway contact angles and loads of ball bearing under different operation conditions obtained by the proposed model and the Jones’ model with different raceway control hypotheses has been conducted. The results show that the proposed model has a higher applicability and rationality compared to the Jones’ model, and a proper moment load can be used to improve the load distribution and service performance of ball bearing subjected to the radial load.

The contamination status of H5 avian influenza viruses and distribution of subtypes of H5N1 and H5N6 in poultry-related environment of Hubei areas were investigated. Urban and rural live poultry markets, poultry farms, intensive livestock farms and other monitoring types of 103 counties in 17 cities were selected in Hubei. Wiping samples from cage surface, wiping samples from chopping board, fecal specimens and other environmental samples were collected and tested by real-time RT-PCR using primers and probes of influenza A, avian influenza of H5, N1 and N6 from December 2017 to March 2018. The avian influenza virus positive rate was compared among different monitoring sites, samples, time and regions. Totally, 7132 environmental samples were collected in 1634 monitoring points with a positive rate of 2.24%. The positive rate of H5 avian influenza virus was the highest in urban and rural live poultry markets (3.44%, χ2=61.329, P

To solve the poor cyclability of faradic supercapacitors (SCs), the authors reported a unique porous carbon (PC) coating with “gap shell” structure on carbon fiber cloth (CFC)/NiS2 materials. This gap shell PC coating was fabricated by combining atomic layer deposition (ALD) Al2O3 and molecular layer deposition alucone, followed by carbonization and etching. The as-prepared CFC/NiS2/PC composites were directly used as binder-free electrodes for SCs. Benefited from its novel nanostructure, the CFC/NiS2/PC electrode shows a large specific capacitance of 1034.6 F/g at 1 A/g and considerable rate capability of 67% capacitance, retaining ratio within 1–20 A/g. The cyclability of the CFC/NiS2/PC electrode is enhanced by 50% relative to the mere CFC/NiS2 after 2000 cycles, which is attributed to the gap and electrically conductive PC coating. Hence, this work provides a promising approach to design gap shell layer for improved cyclability of faradic SCs and other practical applications in energy storage electronics.

According to the nickel foam surface defect images with the typical characteristics of complex geometry and texture distribution, a nickel foam surface defect detection method based on spatial-frequency multi-scale block local binary pattern is proposed. First, nonsubsampled contourlet is used to carry out foam nickel image multi-scale decomposition, and therefore, low-frequency sub-band images and high-frequency sub-band images are obtained. The multi-scale block local binary pattern is then used to extract the feature histogram vectors of each block region of low- and high-frequency sub-bands, and the histogram feature vectors of the whole image after cascade are formed. The kernel principal component analysis and support vector machine are adopted to reduce the dimension of the feature histogram vectors and used for the defect classification. Experimental results show that the proposed method of feature extraction can extract more detailed texture information, and the average recognition rate reaches to 90%, which meets an enterprise’s needs.

In order to study the corrosion behavior of magnesium alloys of high performance in the simulated seawater by continuous variable cross section direct extrusion (CVCDE), an electrochemical method and weight loss method were used to study the difference between AZ31 magnesium alloys produced by CVCDE with different numbers of interim dies to examine the electrochemical corrosion behavior and corrosion rate at 3.5 wt.% NaCl solution in this paper. Scanning electron microscopy and x-ray diffraction were used to analyze the morphology of corrosion surfaces and the composition of the corrosion products of samples soaked for different times. The results show that after CVCDE with different numbers of interim dies, the size of the microstructure is refined gradually, and the grain orientation is also different; with the increase in the number of interim dies, the thermodynamic corrosion tendencies are different, and the corrosion resistance of samples extruded by conventional extrusion is relatively good; the charge transfer and material transfer process are the two main factors affecting the corrosion rate, which determines the direction of the electrochemical reaction; the corrosion form of the sample extruded by CVCDE is the local corrosion which is the filiform corrosion and pitting corrosion, and the corrosion product is mainly water-insoluble Mg(OH)2.

With the development of robotics, the application of robots has gradually evolved from industrial scenes to more intelligent service scenarios. For multitasking operations of robots in complex and uncertain environments, the traditional manual coding method is not only cumbersome but also unable to adapt to sudden changes in the environment. Imitation learning that avoids learning skills from scratch by using the expert demonstration has become the most effective way for robotic manipulation. The paper is intended to provide the survey of imitation learning of robotic manipulation and explore the future research trend. The review of the art of imitation learning for robotic manipulation involves three aspects that are demonstration, representation and learning algorithms. Towards the end of the paper, we highlight areas of future research potential.

At present, flexible die medium represented by fluid is mainly used in tube hydropiercing, but it is relatively rare in sheet forming field because of the high requirement of sealing. For this reason, magnetorheological fluid, one of the representatives of intelligent materials, is used as a force transfer medium to provide backpressure for the piercing process of sheet for the first time in this paper, so as to reduce the collapse and improve the quality of fracture surface. The results show that with the increase of internal pressure, the collapse of the area near the cutting edge of punch decreases, the length of burnish zone increases, the aperture is closer to the nominal diameter, and the quality of the hole is significantly improved. The theoretical mechanics model of a single straight chain is established through theoretical analysis, and the magnitude and loading mode of the force exerted on the sheet by magnetic medium are deduced. Through the balanced relationship between punching force and backpressure in the deformed area of sheet, the key parameters affecting the collapse of piercing of sheet are obtained, which has important guiding significance for improving the quality of sheet metal piercing products with magnetic medium.

This paper proposes an improved Retinex theory based on a weighted guided filter method to enhance images in low-light conditions. The captured images under low illumination can cause dimness, distortion or details loss. We use the weighted guided filter method to perform illumination estimation and the original image is regarded as the guidance image, which can avoid color distortion and over-enhancement. It can adjust the regularization parameter adaptively based on the image content. Perceptual contrast is improved by using an illumination enhancement method with dynamic adjustment. To test the validness of our algorithm, the weighted guided filter method proposed in this paper is compared with bilateral filter and the guided filter method. Finally, experiment under low illumination is implemented on a NAO robot by using the proposed weighted guided filter method based on EKF-SLAM. The experiment result demonstrates that the proposed weighted guided filter method is feasible and effective in low-light environment.

Traditional curved products are obtained in two steps, which consist of an extrusion process and a bending process. There are many bottlenecks to this, such as long processing cycle, low efficiency, and difficulty in controlling the product quality. In this paper, a new staggered extrusion (SE) process was proposed to obtain magnesium alloy bending products. Bending products can be extruded by a staggered punch which has a step-like structure at one end. The experimental results show that with increased staggered distance (h) of the punch, the bending height of the bending products increased significantly. Compared with traditional extrusion, the grains of the bending products obtained by SE are refined. The increase in h is one of the reasons for the asymmetric distribution of axial velocity at the die exit of AZ31 magnesium alloy bending products. The asymmetric distribution of the flow velocity field of bending products during SE is one of the contributors for the bending characteristics to the bending products. The SE enables the use of extrusion in many applicable fields and enriches the types of bending products.

With the rapid increase in anthropogenic activities, the local emissions of polycyclic aromatic hydrocarbons (PAHs) in background regions, such as the Tibetan Plateau (TP), have attracted great attention. The deposition of PAHs in lake sediments provides a historical evolutionary record of such compounds in these regions. To investigate the evolution of PAHs in the TP, two sedimentary cores from Yamzho Yumco Lake were collected and dated at high resolution, and the concentrations of 16 PAHs and sediment properties were also analyzed. The total concentrations of the 16 PAHs ranged from 6.52 to 57.97 ng/g (dry weight) in YC1 and from 0.91 to 4.57 ng/g (dry weight) in YC2. According to the methods of principal component analysis (PCA) followed by multilinear regression analysis (MLRA), four sources of PAHs in the sediments were qualitatively and quantitatively identified, such as petroleum combustion, petrogenic, coal combustion, and biomass burning. Thus, the historical evolution of PAHs was summarized. In addition, the transported distance from local PAH emission sources was found to greatly affect the composition and concentration of PAHs in sites YC1 and YC2. Specifically, local sources contributed a greater proportion of heavy molecular weight (HMW) PAHs in YC1 and a higher proportion of light-molecular-weight (LMW) PAHs in YC2. Moreover, fine particles (size

Spindle-holder interface is the weakest part of the spindle system, and to some extent, determines the dynamics of spindle systems and strongly affects the cutting process stability. In order to improve the spindle system during the design stage and predict the tool point dynamics, this paper proposes modelling of spindle-holder assembly and presents an investigation on the contact characteristic under clamping and centrifugal forces. Modal test results show a good agreement with the simulated results. After that, contact pressure distribution under different clamping and centrifugal forces are investigated, which indicates a decrease of natural frequency of spindle-holder assembly caused by rotational speed. In the last, an improvement of holder dimensions based on the deformations of spindle and holder is presented, and the results show a significantly improved performance of spindle-holder assembly under the rotating condition.

The change rules associated with hot deformation of FGH96 alloy were investigated by isothermal two-pass hot deformation tests in the temperature range 1050–1125°C and at strain rates ranging from 0.001 to 0.1 s−1 on a Gleeble 3500 thermo-simulation machine. The results showed that the softening degree of the alloy between passes decreases with increasing temperature and decreasing strain rates. The critical strain of the first-pass is greater than that of the second-pass. The true stress-true strain curves showed that single-peak dynamic recrystallization, multi- peak dynamic recrystallization, and dynamic response occur when the strain rate is 0.1, 0.01, and 0.001 s−1, respectively. The alloy contains three different grain structures after hot deformation: partially recrystallized tissue, completely fine recrystallized tissue, coarse-grained grains. The small-angle grain boundaries increase with increasing temperature. Increasing strain rates cause the small-angle grain boundaries to first increase and then decrease.

Ductal carcinoma in situ (DCIS) is the most common type of pre-invasive breast cancer diagnosed in women. Because the majority of DCIS cases are unlikely to progress to invasive breast cancer, many women are over-treated for DCIS. By understanding the molecular basis of early stage breast cancer progression, we may identify better prognostic factors and design treatments tailored specifically to the predicted outcome of DCIS. Chemokines are small soluble molecules with complex roles in inflammation and cancer progression. Previously, we demonstrated that CCL2/CCR2 chemokine signaling in breast cancer cell lines regulated growth and invasion through p42/44MAPK and SMAD3 dependent mechanisms. Here, we sought to determine the clinical and functional relevance of CCL2/CCR2 signaling proteins to DCIS progression. Through immunostaining analysis of DCIS and IDC tissues, we show that expression of CCL2, CCR2, phospho-SMAD3 and phospho-p42/44MAPK correlate with IDC. Using PDX models and an immortalized hDCIS.01 breast epithelial cell line, we show that breast epithelial cells with high CCR2 and high CCL2 levels form invasive breast lesions that express phospho-SMAD3 and phospho-p42/44MAPK. These studies demonstrate that increased CCL2/CCR2 signaling in breast tissues is associated with DCIS progression, and could be a signature to predict the likelihood of DCIS progression to IDC.

Macrophage migration inhibitory factor (MIF) is an essential mediator of atherosclerotic plaque progression and instability leading to intracoronary thrombosis, therefore contributing to coronary artery disease (CAD). In this study, we investigated the relationship between MIF gene polymorphism and CAD in Chinese Han population. Three single nucleotide polymorphisms (SNP, rs755622, rs1007888 and rs2096525) of MIF gene were genotyped by TaqMan genotyping assay in 1120 control participants and 1176 CAD patients. Coronary angiography was performed in all CAD patients and Gensini score was used to assess the severity of coronary artery lesions. The plasma levels of MIF and other inflammatory mediators were measured by ELISA. The CAD patients had a higher frequency of CC genotype and C allele of rs755622 compared with that in control subjects (CC genotype: 6.5% vs. 3.9%, P = 0.008, C allele: 24.0% vs. 20.6%, P = 0.005). The rs755622 CC genotype was associated with an increased risk of CAD (OR: 1.804, 95%CI: 1.221–2.664, P = 0.003). CAD patients with a variation of rs755622 CC genotype had significantly higher Gensini score compared with patients with GG or CG genotype (all P P MIF gene rs755622 variation and CAD in Chinese Han population. Individuals who carrying MIF gene rs755622 CC genotype were more susceptible to CAD and had more severe coronary artery lesion. This variation also had a potential influence in circulating MIF levels.

Hypertrophic scar (HS) formation is a skin fibroproliferative disease that occurs following a cutaneous injury, leading to functional and cosmetic impairment. To date, few therapeutic treatments exhibit satisfactory outcomes. The mechanical force has been shown to be a key regulator of HS formation, but the underlying mechanism is not completely understood. The Piezo1 channel has been identified as a novel mechanically activated cation channel (MAC) and is reportedly capable of regulating force-mediated cellular biological behaviors. However, the mechanotransduction role of Piezo1 in HS formation has not been investigated. In this work, we found that Piezo1 was overexpressed in myofibroblasts of human and rat HS tissues. In vitro, cyclic mechanical stretch (CMS) increased Piezo1 expression and Piezo1-mediated calcium influx in human dermal fibroblasts (HDFs). In addition, Piezo1 activity promoted HDFs proliferation, motility, and differentiation in response to CMS. More importantly, intradermal injection of GsMTx4, a Piezo1-blocking peptide, protected rats from stretch-induced HS formation. Together, Piezo1 was shown to participate in HS formation and could be a novel target for the development of promising therapies for HS formation.

Locality preserving projections (LPP) is a popular unsupervised dimensionality reduction method based on manifold learning. As a supervised version of the LPP method, discriminant locality preserving projections (DLPP) method has been recently proposed and paid much attention to by researchers. However, the DLPP method has the small-sample-size (SSS) problem. In this paper, in the view of the eigenvalues of scattering matrices of DLPP, they are first mapped to the new values by two polynomial functions, and with the properties of the matrix function of the two polynomial functions, the criterion of the DLPP method is reconstructed; thus, a novel dimensionality reduction method, named polynomial discriminant locality preserving projections (PDLPP) method, is proposed. The proposed PDLPP method has two advantages: one is that it addresses the SSS problem of DLPP, and the other is that, with the nonlinear mapping implied by PDLPP, the distance between inter-class samples is much enlarged and then the better performance of pattern classification is achieved. The experiments are conducted on the COIL-20 database, ORL, Georgia Tech, and AR face datasets, and the results show that the PDLPP is superior to state-of-the-art methods.

Background The investigation of mesenchymal stromal cell (MSC)-conditioned medium or extracellular vesicles (exosomes or microvesicles) as a remedy for acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) has become a fast-growing field in recent years. Our purpose was to conduct a meta-analysis to investigate the efficacy of MSC-derived therapies (MDTs) for ALI/ARDS in animal models. Methods A meta-analysis of MDTs for ALI/ARDS in animal trials was performed. PubMed and EMBASE were searched to screen relevant preclinical trials with a predetermined search strategy. Results A total of 17 studies that compared MDT with the ALI control group were included in our study. The pooled result derived from the comparison of the two groups suggested that MDT could significantly reduce the lung injury score (standardized mean difference (SMD) = − 4.02, 95% CI [− 5.28, − 2.23], P Conclusion MDT reduces lung injury and improves survival in animal ARDS models since it can ameliorate lung permeability, decrease inflammatory cell infiltration, downregulate proinflammatory mediators, and upregulate anti-inflammatory mediators. However, more animal studies and human trials are needed for further investigation.

Background Machado-Joseph disease is the most common autosomal dominant hereditary ataxia worldwide without effective treatment. Mesenchymal stem cells (MSCs) could slow the disease progression, but side effects limited their clinical application. Besides, MSC-derived exosomes exerted similar efficacy and have many advantages over MSCs. The aim of this study was to examine the efficacy of MSC-derived exosomes in YACMJD84.2 mice. Methods Rotarod performance was evaluated every 2 weeks after a presymptomatic administration of intravenous MSC-derived exosomes twice in YACMJD84.2 mice. Loss of Purkinje cells, relative expression level of Bcl-2/Bax, cerebellar myelin loss, and neuroinflammation were assessed 8 weeks following treatment. Results MSC-derived exosomes were isolated and purified through anion exchange chromatography. Better coordination in rotarod performance was maintained for 6 weeks in YACMJD84.2 mice with exosomal treatment, compared with those without exosomal treatment. Neuropathological changes including loss of Purkinje cells, cerebellar myelin loss, and neuroinflammation were also attenuated 8 weeks after exosomal treatment. The higher relative ratio of Bcl-2/Bax was consistent with the attenuation of loss of Purkinje cells. Conclusions MSC-derived exosomes could promote rotarod performance and attenuate neuropathology, including loss of Purkinje cells, cerebellar myelin loss, and neuroinflammation. Therefore, MSC-derived exosomes have a great potential in the treatment of Machado-Joseph disease.

Allergic airway inflammation is a major public health disease that affects up to 300 million people in the world. However, its management remains largely unsatisfactory. The dysfunction of pulmonary macrophages contributes greatly to the development of allergic airway inflammation. It has been reported that small extracellular vesicles derived from mesenchymal stromal cells (MSC-sEV) were able to display extensive therapeutic effects in some immune diseases. This study aimed to investigate the effects of MSC-sEV on allergic airway inflammation, and the role of macrophages involved in it. We successfully isolated MSC-sEV by using anion exchange chromatography, which were morphologically intact and positive for the specific EV markers. MSC-sEV significantly reduced infiltration of inflammatory cells and number of epithelial goblet cells in lung tissues of mice with allergic airway inflammation. Levels of inflammatory cells and cytokines in bronchoalveolar lavage fluid were also significantly decreased. Importantly, levels of monocytes-derived alveolar macrophages and M2 macrophages were significantly reduced by MSC-sEV. MSC-sEV were excreted through spleen and liver at 24 h post-administration in mice, and were able to be taken in by macrophages both in vivo and in vitro. In addition, proteomics analysis of MSC-sEV revealed that the indicated three types of MSC-sEV contained different quantities of proteins and shared 312 common proteins, which may be involved in the therapeutic effects of MSC-sEV. In total, our study demonstrated that MSC-sEV isolated by anion exchange chromatography were able to ameliorate Th2-dominant allergic airway inflammation through immunoregulation on pulmonary macrophages, suggesting that MSC-sEV were promising alternative therapy for allergic airway inflammation in the future.

In order to further enrich the existing manufacturing methods and approaches of magnesium alloy sheet forming, a new process of circumferential extending extrusion forming of magnesium alloy sheet, which focuses on the process principle and characteristics of the method, is proposed in this paper. Through theoretical analysis, technological theoretical models such as the dimension relationship between the original billet and the formed sheet and the extrusion speed were deduced. The circumferential extending extrusion process of AZ31 magnesium alloy sheets was experimented. The results show that the backpressure ring of pure aluminum can change the stress state of the sheet during extending extrusion and effectively restrain the change of sheet thinning trend and cracking defects at the outer edge caused by tensile stress, and the product quality is improved remarkably. According to the actual requirements, the size of the required sheets can be customized. It can be seen from the comparison that as the distance from the axis increases, the average grain size of the product decreases remarkably, and and the degree of recrystallization is higher. Meanwhile, the microstructure is refined. With the maturity of the process, it is expected to provide a new idea for the short-process forming of high-performance lightweight alloy sheets.

Pneumatic soft actuator is a crucial component of soft robot. This paper proposes several pneumatic control schemes implemented with proportional and PWM-solenoid valves to achieve optimal control for pneumatic soft actuators adapted to different soft robots, such as soft gripper and soft humanoid hand. The schemes include: proportional valve; 3/2-way PWM-solenoid valve; 2/2-way PWM-solenoid valve. The control framework of these schemes contains human–machine interface in upper computer and control algorithm in lower computer. Sinusoidal and multi-step signals are served as reference input to draw a comparison of pressure tracking precision, steady-state accuracy and responsibility of these proposed schemes. The experimental results show that the scheme of proportional valve is more excellent than those of the PWM-solenoid valves, and the scheme of 3/2-way is superior to that of 2/2-way with regard to PWM-solenoid valve. Considering the cost, the scheme of 3/2-way PWM-solenoid valve is the most suitable choice for the system with multi-channel soft actuators. Therefore, the research achievement of this paper is providing a valuable suggestion on balancing the performance and cost for different soft robotic system applications.

A prediction model of thermal contact conductance is developed. Engineering rough surfaces are characterized by three-dimensional fractal Weierstrass-Mandelbrot fractal function. Three deformation modes, including fully plastic deformation, elasto-plastic deformation and elastic deformation, are considered to analyze the contact mechanism. Fractal surface and three deformation modes are incorporated into the calculation of thermal contact conductance. A comprehensive thermal contact conductance computation model considering both base thermal resistance and constricted thermal resistance is established. The results show that thermal contact conductance increases with the increase of normal contact pressure; the relative contribution of constricted resistance component to base resistance component tends to increase with the increase of normal contact pressure; fractal dimension and fractal roughness both have significant influences on thermal contact conductance.

Little is known about the REEs characteristics and distribution in groundwater in the Simao Basin in southwest China. In this study, hydrochemical analyses and models are used to examine the REE inorganic speciation, characteristics and controls of REE concentrations, and fractionation of spring waters in different types of rocks in the basin. REE contents in the spring waters are relatively low, which are positively correlated with TDS. Relatively high concentrations of REEs are observed in the spring waters in the red beds rather than in the carbonate rocks. Speciation calculations indicate that dissolved REEs mainly composed of LnCO3+ and Ln(CO3)2− complexes (the sum ranging from 30.8 to 98.2%). The carbonate complexes account for a larger proportion in the spring waters in the carbonate rocks than in the red beds. LnSO4+ also accounts for a certain proportion up to 67.5% in the spring waters in the red beds. Relatively low pH and Eh values and high concentration of HCO3 contribute to the REEs enrichment in the groundwater. Carbonate complexation and preferential adsorption may result in the enrichment of MREEs and HREEs. The positive Eu anomalies in the spring waters are related to the interaction of groundwater with the carbonate rocks, because Eu can exist in the Ca site of certain calcium-rich minerals (especially carbonate rocks). The negative Ce anomalies are related to redox conditions. Under the oxidation conditions, Ce3+ is oxidized to Ce4+ and coprecipitates with oxides of iron and manganese in the form of CeO2 or Ce(OH)4.

With improved screening methods, the numbers of abnormal breast lesions diagnosed in women have been increasing over time. However, it remains unclear whether these breast lesions will develop into invasive cancers. To more effectively predict the outcome of breast lesions and determine a more appropriate course of treatment, it is important to understand the underlying mechanisms that regulate progression of non-invasive lesions to invasive breast cancers. A hallmark of invasive breast cancers is the accumulation of fibroblasts. Fibroblast proliferation and activation in the mammary gland is in part regulated by the Transforming Growth Factor beta1 pathway (TGF-β). In animal models, TGF-β suppression of CCL2 and CXCL1 chemokine expression is associated with metastatic progression of mammary carcinomas. Here, we show that transgenic overexpression of the Polyoma middle T viral antigen in the mouse mammary gland of C57BL/6 mice results in slow growing non-invasive lesions that progress to invasive carcinomas in a stage dependent manner. Invasive carcinomas are associated with accumulation of fibroblasts that show decreased TGF-β expression and high levels of CXCL1, but not CCL2. Using co-transplant models, we show that decreased TGF-β signaling in fibroblasts contribute to mammary carcinoma progression through enhancement of CXCL1/CXCR2 dependent mechanisms. Using cell culture models, we show that CXCL1 mediated mammary carcinoma cell invasion through NF-κB, AKT, Stat3 and p42/44MAPK dependent mechanisms. These studies provide novel mechanistic insight into the progression of pre-invasive lesions and identify new stromal biomarkers, with important prognostic implications.

Automatic video summarization, which is a typical cognitive-inspired task and attempts to select a small set of the most representative images or video clips for a specific video sequence, is therefore vital for enabling many tasks. In this work, we develop an interactive Non-negative Matrix Factorization (NMF) method for representative action video discovery. The original video is first evenly segmented into short clips, and the bag-of-words model is used to describe each clip. A temporally consistent NMF model is subsequently used for clustering and action segmentation. Because the clustering and segmentation results may not satisfy user intention, the user-controlled operations MERGE and ADD are developed to permit the user to adjust the results in line with expectations. The newly developed interactive NMF method can therefore generate personalized results.Experimental results on the public Weizman dataset demonstrate that our approach provides satisfactory action discovery and segmentation results.