Search

Apelin-13 may have neuroprotective effects. We aimed to determine whether serum apelin-13 could serve as a potential biomarker for severity, delayed cerebral ischemia (DCI), and prognosis after human aneurysmal subarachnoid hemorrhage (aSAH). In this prospective, observational, cohort, single-center study of 139 patients with aSAH and 139 healthy individuals, serum apelin-13 levels were determined. The indicators of stroke severity were the Hunt-Hess scale and the modified Fisher grading scale. The prognostic parameters were DCI and 6-month worse prognosis (Extended Glasgow Outcome Scale scores of 1–4). Using binary logistic regression analysis, the relationship between serum apelin-13 levels and prognosis was reported as odds ratios (ORs) with 95% confidence intervals (CIs). Under the receiver operating characteristic curve, prognostic abilities were shown as areas under the curve (AUCs) with 95% CIs. Serum apelin-13 levels were substantially lower in patients than in controls (median, 28.8 versus 48.6 ng/ml; P < 0.001), in patients with DCI than in non-DCI patients (median, 14.9 versus 31.6 ng/ml; P < 0.001), and in patients with worse prognosis than in those with good prognosis (median, 16.3 versus 33.7 ng/ml; P < 0.001). Serum apelin-13 levels were independently correlated with Hunt-Hess scores (beta, -6.836; 95% CI, -8.963–4.708; VIF, 2.219; P = 0.001) and modified Fisher scores (beta, -3.350; 95% CI, -6.151–0.549; VIF, 1.562; P = 0.019). Serum apelin-13 levels were an independent predictor of DCI (OR, 0.951; 95% CI, 0.914–0.990; P = 0.022) and worse prognosis (OR, 0.954; 95% CI, 0.916–0.993; P = 0.013). Serum apelin-13 levels significantly differentiated DCI and poor prognosis, with AUCs of 0.753 (95% CI, 0.656–0.850) and 0.791 (95% CI, 0.713–0.868) respectively. Using the Youden method, serum apelin-13 levels < 19.3 ng/ml distinguished the risk of DCI with 64.7% sensitivity and 77.1% specificity, and serum apelin-13 levels < 30.2 ng/ml discriminated the development of worse prognosis with 89.1% sensitivity and 63.4% specificity. Serum apelin-13 levels combined with Hunt-Hess scores and modified Fisher scores displayed a significantly higher AUC than any one of them for prognostic prediction (all P < 0.05). Decreased serum apelin-13 levels, which are strongly correlated with disease severity, independently predicted poor outcomes following aSAH, substantializing serum apelin-13 as a useful prognostic biomarker of aSAH. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials hold great promise as next‐generation efficient emitters due to their theoretical 100% internal quantum efficiency. However, such an intriguing photophysical mechanism is extremely rare in perovskites or their derivatives. Herein, the colloidal synthesis of two‐dimensional CsAgCl2 nanocrystals (NCs) with typical TADF feature is reported first. The TADF mechanism is investigated in detail by combining first‐principles calculations with experimental results, including temperature‐dependent spectral analysis and fs‐transient absorption spectra. A small singlet−triplet state splitting energy (0.082 eV) and a large spatial separation of charge density |Ψ|2 of valence band maximum and conduction band minimum are observed, which are prerequisites for TADF. Moreover, these CsAgCl2 NCs deliver an ultralow X‐ray detection limit of 170.5 nGyair s−1 and a high imaging resolution of 11.5 lp mm−1, much superior to the commercial scintillators. [ABSTRACT FROM AUTHOR]

Background: Whole genome bisulfite sequencing (WGBS), possesses the aptitude to dissect methylation status at the nucleotide-level resolution of 5-methylcytosine (5-mC) on a genome-wide scale. It is a powerful technique for epigenome in various cell types, and tissues. As a recently established next-generation sequencing (NGS) platform, GenoLab M is a promising alternative platform. However, its comprehensive evaluation for WGBS has not been reported. We sequenced two bisulfite-converted mammal DNA in this research using our GenoLab M and NovaSeq 6000, respectively. Then, we systematically compared those data via four widely used WGBS tools (BSMAP, Bismark, BatMeth2, BS-Seeker2) and a new bisulfite-seq tool (BSBolt). We interrogated their computational time, genome depth and coverage, and evaluated their percentage of methylated Cs. Result: Here, benchmarking a combination of pre- and post-processing methods, we found that trimming improved the performance of mapping efficiency in eight datasets. The data from two platforms uncovered ~ 80% of CpG sites genome-wide in the human cell line. Those data sequenced by GenoLab M achieved a far lower proportion of duplicates (~ 5.5%). Among pipelines, BSMAP provided an intriguing representation of 5-mC distribution at CpG sites with 5-mC levels > ~ 78% in datasets from human cell lines, especially in the GenoLab M. BSMAP performed more advantages in running time, uniquely mapped reads percentages, genomic coverage, and quantitative accuracy. Finally, compared with the previous methylation pattern of human cell line and mouse tissue, we confirmed that the data from GenoLab M performed similar consistency and accuracy in methylation levels of CpG sites with that from NovaSeq 6000. Conclusion: Together we confirmed that GenoLab M was a qualified NGS platform for WGBS with high performance. Our results showed that BSMAP was the suitable pipeline that allowed for WGBS studies on the GenoLab M platform. [ABSTRACT FROM AUTHOR]

Al 2 O 3 /graphene nanoplatelets (GNPs) materials were prepared using the spark plasma sintering-high-frequency (SPS-HF) dual sintering method. The mechanical properties and microstructure of the composites were observed, and the effects of the sintering process and GNPs on the composites were analyzed. Under the sintering condition of a temperature of 1350 °C, pressure of 35 MPa and holding time of 8 min, the optimal mechanical properties of Al 2 O 3 ceramic tool materials were obtained. The addition of GNPs had a positive effect on the mechanical properties of Al 2 O 3 materials. Results show that the SPS-HF dual-sintering method shortens sintering time significantly. Compared to Al 2 O 3 ceramic material, the composite material with 0.5 vol% GNPs had better mechanical properties than the Al 2 O 3 ceramic material, with its flexural strength and fracture toughness being increased by 15.3% (617 MPa) and 63.4% (6.7 MPa m1/2), respectively. The toughening mechanisms of Al 2 O 3 /GNPs ceramic nanocomposites are graphene pull-out, graphene breaking, crack deflection, and crack branching. Dry machining tests of 40Cr hardened steel were carried out using an Al 2 O 3 /GNP ceramic tool and an Al 2 O 3 ceramic tool. Compared with the Al 2 O 3 ceramic tool, the life of the Al 2 O 3 /GNPs ceramic tool was increased by 16.3%, the workpiece roughness was decreased by 9.2%, and the friction coefficient was reduced by 12.8%, confirming the improvement of cutting performance by adding GNPs to ceramic tool materials. [ABSTRACT FROM AUTHOR]

Background: Searching the risk factors for carbapenem-resistant Enterobacteriaceae (CRE) infection is important in clinical practice. In the present study, we aim to investigate bacterial characteristics of colonizing strains and their correlation with subsequent CRE infection.Methods: Between May 2018 and January 2019, patients hospitalized in the department of haematology and intensive care unit (ICU) were screened for CRE by rectal swabs and monitored for the outcome of infection. We identified the species and carbapenemase-encoding genes of colonizing strains and performed antimicrobial susceptibility tests and multilocus sequence typing (MLST). Risk factors for subsequent CRE infections were ascertained by univariate and multivariable analysis.Results: We collected a total of 219 colonizing strains from 153 patients. Klebsiella pneumoniae was the most abundant species, and MLST analysis showed rich diversity. K. pneumoniae carbapenemase (KPC) was predominant in the infection group (72.4%). In the non-infection group, 35.4% of strains were non-carbapenemase-producing CRE (NCP-CRE), and New Delhi metallo-β-lactamase (NDM) was predominant (42.2%). The rate of high-level carbapenem resistance (minimum inhibitory concentration [MIC] ≥ 64 mg/L for meropenem and ertapenem, ≥ 32 mg/L for imipenem) was remarkably higher in the infection group than in the non-infection group (P <  0.001). Univariate analysis showed that K. pneumoniae, high-level carbapenem resistance, CP-CRE and KPC-CRE were infection risk factors after CRE colonization. On multivariable analysis with different carbapenemase dichotomizations, KPC-CRE (adjusted odds ratio [aOR], 4.507; 95% confidence interval [CI], 1.339-15.171; P = 0.015) or imipenem MIC ≥ 32 mg/L (aOR, 9.515; 95% CI, 1.617-55.977; P = 0.013) were respectively identified as independent risk factors for subsequent infection.Conclusions: Patients colonized with KPC-CRE or strains with an imipenem MIC ≥ 32 mg/L were at particularly high risk of subsequent CRE infections during their hospital stay. [ABSTRACT FROM AUTHOR]

This paper considers an optimal train control problem with two challenging, non-standard constraints: a speed constraint that is piecewise-constant with respect to the train's position, and control constraints that are non-smooth functions of the train's speed. We formulate this problem as an optimal switching control problem in which the mode switching times are decision variables to be optimized, and the track gradient and speed limit in each mode are constant. Then, using control parameterization and time-scaling techniques, we approximate the switching control problem by a finite-dimensional optimization problem, which is still subject to the challenging speed limit constraint (imposed continuously during each mode) and the non-smooth control constraints. We show that the speed constraint can be transformed into a finite number of point constraints. We also show that the non-smooth control constraints can be approximated by a sequence of conventional (smooth) inequality constraints. The resulting approximate problem can be viewed as a nonlinear programming problem and solved using gradient-based optimization algorithms, where the gradients of the cost and constraint functions are computed via the sensitivity method. A case study using data for a real subway line shows that the proposed method yields a realistic optimal control profile without the undesirable control fluctuations that can occur with the pseudospectral method. [ABSTRACT FROM AUTHOR]

• Serum macrophage migration inhibitory factor levels are raised after brain trauma. • Serum macrophage migration inhibitory factor levels are correlated with clinical severity following brain trauma. • Serum macrophage migration inhibitory factor appears as an independent predictor for cerebrocardiac syndrome. Cerebrocardiac syndrome (CCS) is a common complication after severe traumatic brain injury (sTBI) and its occurrence obviously increases the risk of a poor outcome. Macrophage migration inhibitory factor (MIF) acts as an inflammatory cytokine and its circulating concentration are related to acute heart and brain injury. The aim of this study was to examine the association of serum concentration of MIF with posttraumatic CCS. From January 2016 to February 2019, 116 sTBI patients and 116 healthy controls with similar age and gender percentage were recruited. Relationship between serum MIF concentration and CCS was assessed using multivariate analysis. Serum MIF concentration of patients were significantly higher than those among controls. Serum MIF concentration were intimately correlated with Glasgow coma scale scores (t = -5.553, P < 0.001) and serum C-reactive protein concentration (t = 5.320, P < 0.001) in a multivariate linear regression model. 61 patients (52.6%) displayed CCS. Under ROC curve analylsis, there was a strong discriminatory ability for CCS regarding serum MIF concentration (area under curve, 0.834; 95% confidence interval, 0.754–0.897). Serum MIF concentration were highly associated with CCS independent of other confounding factors (odds ratio, 5.608; 95% CI: 1.896–16.587). Increased MIF in serum may be a useful biomarker for early detection of CCS after head trauma. [ABSTRACT FROM AUTHOR]

• There is a substantial elevation in serum sLOX-1 levels after aSAH. • There is an intimate correlation of serum sLOX-1 levels with hemorrhagic severity. • There is an independent association of serum sLOX-1 levels with worse prognosis. Oxidized low-density lipoprotein (ox-LDL) and its receptor, lectin-like ox-LDL receptor-1 (LOX-1) are involved in the pathogenesis of atherosclerosis. Expression of LOX-1 was substantially raised in the basilar arterial wall of subarachnoid hemorrhage (SAH) rabbits. We ascertained the relationship between serum soluble LOX-1 concentrations and functional outcome after human aneurysmal SAH. We enrolled 94 aneurysmal SAH patients and 94 healthy controls. Serum soluble TOX-1 concentrations were quantified using commercial enzyme-linked immunosorbent assay kit. A poor outcome was defined as Glasgow outcome scale score of 1–3. Median values of serum soluble LOX-1 in stroke patients were significantly higher than those in controls (1.5 vs. 0.4 ng/ml, P < 0.001). Thirty patients (31.9%) had a poor outcome at 6 months after stroke. Serum soluble LOX-1 was a strong predictor of poor outcome (OR 5.20, 95% CI 1.25–22.04). Serum soluble LOX-1 concentrations exhibited a significant discriminatory capability (area under curve 0.811, 95% confidence interval 0.717–0.884). The predictive powers of World Federation of Neurological Surgeons grade, Hunt-Hess grade, modified Fisher grade, and serum soluble LOX-1 concentrations were comparable (all P > 0.05). Serum soluble LOX-1 appears to have the potential to become a promising prognostic predictor after human aneurysmal SAH. [ABSTRACT FROM AUTHOR]

Information and Communication Technology (ICT) has improved education widely in China, transforming traditional teaching into an interactive one. It is important to build a new evaluation model to measure teaching efficiency in an "ICT-enabled classroom". This study designed an evaluation model named "TPOCME Deep classroom" through ongoing five iterations. It includes six dimensions, which are higher-order Thinking, classroom Participation, Openness of educational system, Cooperative learning, Meaningful learning and Effectiveness of technology use (named TPOCME). This model helps educational researchers and teachers gain a comprehensive understanding of ICT in education. [ABSTRACT FROM AUTHOR]

Tumor sensitivity to radiation therapy has been known to be dependent on O2 concentrations. However, radiosensitivity of naturally occurring hypoxic tumor cells remains to be well fully investigated in direct comparison to that of their adjacent non-hypoxic tumor cells within the same tumor. We developed a hypoxia-sensing xenograft model using the hypoxia-response element (HRE)-driven enhanced green fluorescence protein (EGFP) as a hypoxia reporter to identify hypoxic tumor cells in situ. Here, we have found that naturally hypoxic tumor cells are moderately radioresistant compared to their neighboring non-hypoxic tumor cells in the same tumor. These naturally hypoxic tumor cells are proficient at repairing DNA damages and resist apoptosis induced by genotoxic stresses, which involves activation of the ATM/CHK1/CHK2 DNA damage-sensing pathway. Inhibition of the checkpoint kinases sensitizes the ex vivo hypoxic tumor cells to ionizing irradiation. Second, the new functional phenotypes acquired by the hypoxic tumor cells in vivo are stable even after they are maintained under non-hypoxic conditions. These new results strongly suggest that the hypoxic tumor microenvironment is capable of selecting stable tumor cell populations with increased resistance to genotoxic stresses and enhanced survival. [ABSTRACT FROM AUTHOR]

Based on quaternion discrete cosine transform (QDCT) and singular value decomposition (SVD), a novel color image watermarking scheme using an optimized encrypted binary computer-generated hologram (CGH) as the watermark is presented. A Fibonacci transform-based binary CGH technique that uses particle swarm optimization (PSO) algorithm to improve the reconstructed image quality has been proposed to generate a hologram of a watermark. By use of QDCT, the host color image is treated holistically as a vector field. The component of the host color image after QDCT, which is suitable for embedding watermark, is analyzed. With SVD, the mark CGH is inserted into the host color image by modifying the U matrix. To embed the binary CGH, multiple embedding strength factors are used in this study. To withstand the geometric attacks, based on Zernike moment algorithm and invariant centroid, an improved geometric distortion detection algorithm is proposed. Considering the significant color information, this algorithm is performed on the color invariance model. To obtain better imperceptibility and robustness, PSO is used for finding the proper multiple embedding strength factors. Compared with traditional geometric estimation method, the improved algorithm can estimate the transform parameters of the geometric distorted color image more accurately. Experimental results show that the proposed color image watermarking is not only secure and invisible, but also robust against common image processing operations and geometrical distortions. [ABSTRACT FROM AUTHOR]

As a novel antibiotic resistance mobile element, integron was recognized as a primary source of antibiotic genes among Gram-positive organisms for its excision and integration of exogenous genes. In this study, Streptococcus pneumoniae was subjected to investigate the excision and integration of class 1 integron with eight different plasmids. As the results indicated, excision in both att site and gene cassettes were successfully observed, which was further confirmed by integration assays and PCR amplification. The observation of class 1 integron mediated excision and integration of various exogenous antibiotics resistance genes may raise the attention of integrons as novel antibiotic resistance determinant in Gram-positive bacteria, especially in Streptococcus . [ABSTRACT FROM AUTHOR]

Diatoms are important components of marine ecosystems and contribute greatly to the world’s primary production. Despite their important roles in ecosystems, the molecular basis of how diatoms cope with oxidative stress caused by nutrient fluctuations remains largely unknown. Here, an isobaric tags for relative and absolute quantitation (iTRAQ) proteomic method was coupled with a series of physiological and biochemical techniques to explore oxidative stress- and cell fate decision-related cellular and metabolic responses of the diatom Thalassiosira pseudonana to nitrate (N) and inorganic phosphate (P) stresses. A total of 1151 proteins were detected; 122 and 56 were significantly differentially expressed from control under N- and P-limited conditions, respectively. In N-limited cells, responsive proteins were related to reactive oxygen species (ROS) accumulation, oxidative stress responses and cell death, corresponding to a significant decrease in photosynthetic efficiency, marked intracellular ROS accumulation, and caspase-mediated programmed cell death activation. None of these responses were identified in P-limited cells; however, a significant up-regulation of alkaline phosphatase proteins was observed, which could be the major contributor for P-limited cells to cope with ambient P deficiency. These findings demonstrate that fundamentally different metabolic responses and cellular regulations are employed by the diatom in response to different nutrient stresses and to keep the cells viable. [ABSTRACT FROM AUTHOR]

Iodine-modified ZnO with oxygen vacancies were synthesized by the solvothermal method. The crystal structure, morphology, optical properties and defects of as-prepared samples were characterized by XRD, SEM, DRS, XPS and ESR. The photocatalytic disinfection activity of I-modified ZnO in the dark and under visible light irradiation were investigated by the antibacterial drop-test method. The results showed that the iodine mainly exists in the form of I in the ZnO. The modified iodine increases the numbers of oxygen vacancies of ZnO as the amount of iodine increases. In addition, the I-ZnO exhibits much higher antibacterial activity than that of pure ZnO and was stable during the photocatalytic process. The enhanced antibacterial activity of I-ZnO is attributed to the co-operation of the oxygen vacancies and the iodine which promotes the separation of photo-generated carriers and subsequently produces more ROS (reactive oxygen species). Graphical Abstract: [ABSTRACT FROM AUTHOR]

Background Intracerebral hemorrhage (ICH) pathophysiology involves inflammation. Macrophage migration inhibition factor (MIF), a pro-inflammatory cytokine, is related to prognosis of ischemic stroke. The aim of this study was to investigate whether serum MIF levels are associated with severity and outcomes in patients with acute ICH. Methods We enrolled a total of 120 consecutive ICH patients and 120 healthy controls and sampled blood on admission and at study entry respectively. Enzyme-linked immunosorbent assay was used to quantify serum MIF levels. Results Serum MIF levels were higher in patients compared with controls and correlated with hematoma volume, National Institutes of Health Stroke Scale (NIHSS) scores and plasma C-reactive protein levels. After adjusting for other significant outcome predictors, MIF in serum was an independent predictor of 6-month overall survival and unfavorable outcome (modified Rankin Scale score > 2). Areas under receiver-operating characteristic curve (ROC) of serum MIF levels, hematoma volume and NIHSS scores were similar for 6-month unfavorable outcome. Moreover, serum MIF levels significantly improved areas under ROC of hematoma volume and NIHSS scores. Conclusions MIF in serum might be a potential biomarker for reflecting inflammation, severity and prognosis of ICH patients. [ABSTRACT FROM AUTHOR]

Loop-mediated isothermal amplification based detection assays using bacterial culture or colony for direct detection of methicillin resistant Staphylococcus aureus (MRSA) had been developed and evaluated, followed by its extensive application on a large scale of clinical MRSA isolated from respiratory origins, including nasal swabs and sputums. Six primers, including outer primers, inner primers and loop primers, were specifically designed for recognizing eight distinct sequences on four targets: 16SrRNA, femA , mecA and orfX. Twenty-seven reference strains were used to develop, evaluate and optimize this assay. Then, a total of 532 clinical MRSA isolates were employed for each detected targets. And the results were determined through both visual observation of the color change by naked eye and electrophoresis. The specific of each primer had been confirmed, and the optimal amplification was obtained under 65 °C for 40 min. The limit of detections (LOD) of bacteria culture LAMP assays were determined to be 10 4 CFU/ml for 16S rRNA, femA , as well as orfX and 10 5 CFU/ml for mecA , respectively. The established novel assays on MRSA detection may provide new strategies for rapid detection of foodborne pathogens. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is primarily characterized by progressive degeneration and destruction of articular cartilage. Currently, there is no effective method to treat OA. The metabolic disturbance of cartilage extracellular matrix (ECM) and oxidative stress are critical to promote OA progression. Galangin (Gal) is a small molecule compound that pertains to flavonoids. To determine the protective effect and mechanism of Gal against OA progression, various experiments were performed in vitro and in vivo. In vitro, Gal promoted ECM production and attenuated ECM degradation in human OA chondrocytes. The expression of ECM components from human OA cartilage explants was also stimulated by Gal treatment. As demonstrated from the in vivo study, the intra-articular injection of Gal delayed OA progression in rat models. Moreover, RNA sequencing analysis showed that proline/arginine-rich end leucine repeat protein (PRELP) was a molecular target of Gal activity. Gal inhibited oxidative stress and attenuated ECM degradation by activating PRELP expression. The study demonstrated that Gal could attenuate ECM degradation and ameliorate OA progression, and PRELP may be a potential candidate drug of Gal for treating OA. [ABSTRACT FROM AUTHOR]

In this paper, we consider a class of nonlinear time-delay optimal control problems with canonical equality and inequality constraints. We propose a new computational approach, which combines the control parameterization technique with a hybrid time-scaling strategy, for solving this class of optimal control problems. The proposed approach involves approximating the control variables by piecewise constant functions, whose heights and switching times are decision variables to be optimized. Then, the resulting problem with varying switching times is transformed, via a new hybrid time-scaling strategy, into an equivalent problem with fixed switching times, which is much preferred for numerical computation. Our new time-scaling strategy is hybrid in the sense that it is related to two coupled time-delay systems-one defined on the original time scale, in which the switching times are variable, the other defined on the new time scale, in which the switching times are fixed. This is different from the conventional time-scaling transformation widely used in the literature, which is not applicable to systems with time-delays. To demonstrate the effectiveness of the proposed approach, we solve four numerical examples. The results show that the costs obtained by our new approach are lower, when compared with those obtained by existing optimal control methods. [ABSTRACT FROM AUTHOR]

In this paper, a new multilevel correction scheme is proposed to solve Stokes eigenvalue problems by the finite element method. This new scheme contains a series of correction steps, and the accuracy of eigenpair approximation can be improved after each step. In each correction step, we only need to solve a Stokes problem on the corresponding fine finite element space and a Stokes eigenvalue problem on the coarsest finite element space. This correction scheme can improve the efficiency of solving Stokes eigenvalue problems by the finite element method. As applications of this multilevel correction method, a multigrid method and an adaptive finite element technique are introduced for Stokes eigenvalue problems. Some numerical results are given to validate our schemes. [ABSTRACT FROM AUTHOR]

A new evolutionary algorithm, Backtracking Search Algorithm (BSA), is applied to solve constrained optimization problems. Three constraint handling methods are combined with BSA for constrained optimization problems; namely feasibility and dominance (FAD) rules, ε -constrained method with fixed control way of ε value and a proposed ε -constrained method with self-adaptive control way of ε value. The proposed method controls ε value according to the properties of current population. This kind of ε value enables algorithm to sufficiently search boundaries between infeasible regions and feasible regions. It can avoid low search efficiency and premature convergence which happens in fixed control method and FAD rules. The comparison of the above three algorithms demonstrates BSA combined ε -constrained method with self-adaptive control way of ε value (BSA-SA ε ) is the best one. The proposed BSA-SA ε also outperforms other five classic and the latest constrained optimization algorithms. Then, BSA-SA ε has been applied to four engineering optimization instances, and the comparison with other algorithms has proven its advantages. Finally, BSA-SA ε is used to solve the car side impact design optimization problem, which illustrates the wide application prospects of the proposed BSA-SA ε . [ABSTRACT FROM AUTHOR]

This paper considers the problem of using noisy output data to estimate unknown time-delays and unknown system parameters in a general nonlinear time-delay system. We formulate the problem as a dynamic optimization problem in which the unknown quantities are decision variables to be chosen optimally, with the cost function penalizing the mean and variance of the least-squares error between actual and predicted system output. Since the time-delays and system parameters influence the cost function implicitly through the governing time-delay system, the cost function’s gradient–which is required to solve the problem using gradient-based optimization techniques–cannot be computed analytically using standard differentiation rules. We instead develop two computational methods for evaluating this gradient: one involves solving an auxiliary time-delay system forward in time; the other involves solving an auxiliary time-advance system backward in time. On this basis, we propose an efficient optimization algorithm for determining optimal estimates for the time-delays and system parameters. We conclude the paper by examining the performance of this algorithm on a dynamic model of a continuously-stirred tank reactor. [ABSTRACT FROM AUTHOR]

A type of adaptive finite element method is presented for semilinear elliptic problems based on multilevel correction scheme. The main idea of the method is to transform the semilinear elliptic equation into a sequence of linearized boundary value problems on the adaptive partitions and some semilinear elliptic problems on very low dimensional finite element spaces. Hence, solving the semilinear elliptic problem can reach almost the same efficiency as the adaptive method for the associated boundary value problem. The convergence and optimal complexity of the new scheme can be derived theoretically and demonstrated numerically. [ABSTRACT FROM AUTHOR]

This paper proposes a new optimal control model for the production of 1,3-propanediol (1,3-PD) via microbial fed-batch fermentation. The proposed model is governed by a nonlinear multistage dynamic system with two modes: feeding mode, in which glycerol and alkali substrates are added continuously to the fermentor; and batch mode, in which no substrates are added to the fermentor. The non-standard objective function incorporates both the final 1,3-PD yield and the cost of changing the input feeding rate, which is the control variable for the fed-batch fermentation process. Continuous state inequality constraints are imposed to ensure that the concentrations of biomass, glycerol, and reaction products lie within specified limits. Using the constraint transcription method, we approximate the continuous state inequality constraints by a conventional inequality constraint to yield an approximate parameter optimization problem. We then develop a combined particle swarm and gradient-based optimization algorithm to solve this approximate problem. The paper concludes with simulation results. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present an a posteriori error estimator and the lower bound for a nonconforming finite element approximation, i.e. the extended Crouzeix–Raviart element, of the Laplace eigenvalue problem. Under the guideline of the analysis to the Laplace source problem, we first give out an error indicator and prove it as the global upper and local lower bounds of the approximation error. We also give the lower-bound analysis for this type of nonconforming element on the adaptive meshes. Some numerical experiments are presented to verify our theoretical results. [Copyright &y& Elsevier]

By means of the integral version of vortex equation, the technique of Green's function, and the vorticity-to-velocity map, a new kind of interval methods for solving the initial-periodic boundary value problem of two-dimensional incompressible Navier-Stokes equation is introduced, which consists of both an approximate scheme and a set of pointwise intervals covering the exact solution. The convergence theorem corresponding to the scheme is proved, and the order of error width for the two-sided bounds is also considered. Finally, a simple numerical example illustrates our corroboration. © 2014 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 1368-1396, 2014 [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider a class of nonlinear semi-infinite optimization problems. These problems involve continuous inequality constraints that need to be satisfied at every point in an infinite index set, as well as conventional equality and inequality constraints. By introducing a novel penalty function to penalize constraint violations, we form an approximate optimization problem in which the penalty function is minimized subject to only bound constraints. We then show that this penalty function is exact—that is, when the penalty parameter is sufficiently large, any local solution of the approximate problem can be used to generate a corresponding local solution of the original problem. On this basis, the original problem can be solved as a sequence of approximate nonlinear programming problems. We conclude the paper with some numerical results demonstrating the applicability of our approach to PID control and filter design. [Copyright &y& Elsevier]

Abstract: In any real system, changing the control signal from one value to another will usually cause wear and tear on the system’s actuators. Thus, when designing a control law, it is important to consider not just predicted system performance, but also the cost associated with changing the control action. This latter cost is almost always ignored in the optimal control literature. In this paper, we consider a class of optimal control problems in which the variation of the control signal is explicitly penalized in the cost function. We develop an effective computational method, based on the control parameterization approach and a novel transformation procedure, for solving this class of optimal control problems. We then apply our method to three example problems in fisheries, train control, and chemical engineering. [Copyright &y& Elsevier]

Recent advances highlight that non-coding RNAs (ncRNAs) are emerging as fundamental regulators in various physiological as well as pathological processes by regulating macro-autophagy. Studies have disclosed that macro-autophagy, which is a highly conserved process involving cellular nutrients, components, and recycling of organelles, can be either selective or non-selective and ncRNAs show their regulation on selective autophagy as well as non-selective autophagy. The abnormal expression of ncRNAs will result in the impairment of autophagy and contribute to carcinogenesis and cancer progression by regulating both selective autophagy as well as non-selective autophagy. This review focuses on the regulatory roles of ncRNAs in autophagy and their involvement in cancer which may provide valuable therapeutic targets for cancer management. • The article revises non-coding RNAs (ncRNAs) as new autophagy regulators in carcinogenesis and cancer progression. • Both selective and non-selective autophagy emerge as a double-edged sword in caner. • Therapeutic approaches resversing the abnormal expression of autophagy-related ncRNAs are promising [ABSTRACT FROM AUTHOR]

Simple Summary: Distant metastasis, especially bone metastasis, is the major cause of death in breast cancer patients. However, breast cancer patients with bone metastasis are frequently complicated by delayed intervention as clinically bone metastasis cannot be detected early enough. Here, we report that CTNND1 is downregulated in both primary tumors and metastatic bone lesions of patients with triple-negative breast cancer (TNBC). Decreased CTNND1 is a crucial intrinsic contributor to homing to the bones and the survival of the breast cancer cells in the bone microenvironment. Thus, CTNND1 may be a novel biomarker for early predicting bone metastasis of triple-negative breast cancer. Bone metastasis from triple-negative breast cancer (TNBC) frequently results in poorer prognosis than other types of breast cancer due to the delay in diagnosis and intervention, lack of effective treatments and more skeletal-related complications. In the present study, we identified CTNND1 as a most reduced molecule in metastatic bone lesion from TNBC by way of high throughput sequencing of TNBC samples. In vivo experiments revealed that knockdown of CTNND1 enhanced tumor cells metastasis to bones and also increased neutrophils infiltration in bones. In vitro, we demonstrated that knockdown of CTNND1 accelerated epithelial–mesenchymal transformation (EMT) of tumor cells and their recruitment to bones. The involvement by CTNND1 in EMT and bone homing was achieved by upregulating CXCR4 via activating the PI3K/AKT/HIF-1αpathway. Moreover, TNBC cells with reduced expression of CTNND1 elicited cytotoxic T-cells responses through accelerating neutrophils infiltration by secreting more GM-CSF and IL-8. Clinically, patients with triple-negative breast cancer and lower level of CTNND1 had shorter overall survival (OS) and distant metastasis-free survival (DMFS). It was concluded that downregulation of CTNND1 played a critical role in facilitating bone metastasis of TNBC and that CTNND1 might be a potential biomarker for predicting the risk of bone metastases in TNBC. [ABSTRACT FROM AUTHOR]

The paper deals with error estimates and lower bound approximations of the Steklov eigenvalue problems on convex or concave domains by nonconforming finite element methods. We consider four types of nonconforming finite elements: Crouzeix-Raviart, Q, EQ and enriched Crouzeix-Raviart. We first derive error estimates for the nonconforming finite element approximations of the Steklov eigenvalue problem and then give the analysis of lower bound approximations. Some numerical results are presented to validate our theoretical results. [ABSTRACT FROM AUTHOR]

The southern Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an ecosystem model to analyze the trophic interactions and ecosystem structure and function to guide sustainable development of the ecosystem. A trophic mass-balance model of the southern Yellow Sea during 2000-2001 was constructed using Ecopath with Ecosim software. We defined 22 important functional groups and studied their diet composition. The trophic levels of fish, shrimp, crabs, and cephalopods were between 2.78 and 4.39, and the mean trophic level of the fisheries was 3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was 8.1%, of which 7.1% was from primary producers and 9.3% was from detritus within the ecosystem. The transfer efficiency between trophic levels II to III to IV to V to >V was 5.0%, 5.7%, 18.5%, and 19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed 61% and detritus contributed 39%. Fishing is defined as a top predator within the ecosystem, and has a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, our data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum's ecological parameters, this ecosystem was at an immature stage. Our results provide some insights into the structure and development of this ecosystem. [ABSTRACT FROM AUTHOR]

In this paper, the authors use the integral identities of triangular linear elements to prove a uniform optimal-order error estimate for the triangular element solution of two-dimensional time-dependent advection-diffusion equations. Also the authors introduce an interpolation postprocessing operator to get the superconvergence estimate under the ε weighted energy norm. The estimates above depend only on the initial and right data but not on the scaling parameter ε. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider a challenging optimal control problem in which the terminal time is determined by a stopping criterion. This stopping criterion is defined by a smooth surface in the state space; when the state trajectory hits this surface, the governing dynamic system stops. By restricting the controls to piecewise constant functions, we derive a finite-dimensional approximation of the optimal control problem. We then develop an efficient computational method, based on nonlinear programming, for solving the approximate problem. We conclude the paper with four numerical examples. [Copyright &y& Elsevier]

In this paper, we consider a class of optimal control problems with free terminal time and continuous inequality constraints. First, the problem is approximated by representing the control function as a piecewise-constant function. Then the continuous inequality constraints are transformed into terminal equality constraints for an auxiliary differential system. After these two steps, we transform the constrained optimization problem into a penalized problem with only box constraints on the decision variables using a novel exact penalty function. This penalized problem is then solved by a gradient-based optimization technique. Theoretical analysis proves that this penalty function has continuous derivatives, and for a sufficiently large and finite penalty parameter, its local minimizer is feasible in the sense that the continuous inequality constraints are satisfied. Furthermore, this local minimizer is also the local minimizer of the constrained problem. Numerical simulations on the range maximization for a hypersonic vehicle reentering the atmosphere subject to a heating constraint demonstrate the effectiveness of our method. [ABSTRACT FROM AUTHOR]

Rannacher discovered by numerical results that the Morley element eigenvalues could approximate the exact eigenvalues from below. This discovery is very important in engineering and mechanics computing. This note provides a theoretical proof for Rannacher's observations. [ABSTRACT FROM AUTHOR]

Abstract: This paper is concerned with blending algebraic implicit curve and surface representation where the functional representations have inaccuracies. Algebraic implicit interval curves and surfaces are first defined as interval algebraic objects. The interval Buchberger algorithm, relying on polynomial interval division, is then outlined. General blending problems for algebraic implicit curves and surfaces are considered and various continuity conditions are applied. Computational cases are developed for specific problems. [Copyright &y& Elsevier]

Abstract: The paper provides a general procedure or method to produce asymptotic error expansion for the eigenvalue approximations of second order elliptic problems by the mixed finite element method. We obtain a transform lemma for the error of the eigenvalue approximations. As an application of the transform lemma, the asymptotic error expansion of the eigenvalue approximations for the second order elliptic problem by the lowest order Raviart–Thomas mixed finite element method is given by means of integral identity technique. Based on such an error expansion, Richardson extrapolation technique is applied to improve the accuracy of the eigenvalue approximations. [Copyright &y& Elsevier]

In this paper we are concerned with finite element approximations to the evaluation of American options. First, following W. Allegretto etc., SIAM J. Numer. Anal. 39 (2001), 834–857, we introduce a novel practical approach to the discussed problem, which involves the exact reformulation of the original problem and the implementation of the numerical solution over a very small region so that this algorithm is very rapid and highly accurate. Secondly by means of a superapproximation and interpolation postprocessing analysis technique, we present sharp L2-, L∞-norm error estimates and an H1-norm superconvergence estimate for this finite element method. As a by-product, the global superconvergence result can be used to generate an efficient a posteriori error estimator. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider the Cauchy problem for a generalized Boussinesq equation. We show that, under suitable conditions, a global solution for the initial value problem exists. In addition, we derive the sufficient conditions for the blow-up of the solution to the problem. [Copyright &y& Elsevier]

MicroRNAs (miRNAs) are involved in a plethora of important biological processes, from embryonic development to homeostasis in adult tissues. Recently, miRNAs have emerged as a class of epigenetic regulators of metabolism and energy homeostasis. We have investigated the role of miRNAs in the regulation of adipogenic differentiation. In this article, we demonstrate that the miR-27 gene family is downregulated during adipogenic differentiation. Overexpression of miR-27 specifically inhibited adipocyte formation, without affecting myogenic differentiation. We also found that expression of miR-27 resulted in blockade of expression of PPARγ and C/EBPα, the two master regulators of adipogenesis. Importantly, expression of miR-27 was increased in fat tissue of obese mice and was regulated by hypoxia, an important extracellular stress associated with obesity. Our data strongly suggest that miR-27 represents a new class of adipogenic inhibitors and may play a role in the pathological development of obesity. [ABSTRACT FROM AUTHOR]

Abstract: The paper explores new expansions of eigenvalues for in with Dirichlet boundary conditions by Wilson’s element. The expansions indicate that Wilson’s element provides lower bounds of the eigenvalues. By the extrapolation or the splitting extrapolation, the convergence rate can be obtained, where is the maximal boundary length of uniform rectangles. Numerical experiments are carried to verify the theoretical analysis made. It is worth pointing out that these results are new, compared with the recent book, Lin and Lin [Q. Lin, J. Lin, Finite Element Methods; Accuracy and Improvement, Science Press, Beijing, 2006]. [Copyright &y& Elsevier]

Abstract: In this paper, we develop and validate a numerical procedure for solving a class of initial boundary value problems for the improved Boussinesq equation. The finite element method with linear B-spline basis functions is used to discretize the nonlinear partial differential equation in space and derive a second order system involving only ordinary derivatives. It is shown that the coefficient matrix for the second order term in this system is invertible. Consequently, for the first time, the initial boundary value problem can be reduced to an explicit initial value problem to which many accurate numerical methods are readily applicable. Various examples are presented to validate this technique and demonstrate its capacity to simulate wave splitting, wave interaction and blow-up behavior. [Copyright &y& Elsevier]

Abstract: In this paper, we study the superconvergence of the frictionless Signorini problem. When approximated by bilinear finite elements, by virtue of the information on the contact zone, we can derive a superconvergence rate of under a proper regularity assumption. Finally, a numerical test is given to verify our result. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the following problem where is a bounded domain with smooth boundary. Under some assumptions of the initial data , and the nonlinear function , the existence of global weak solutions and global strong solutions are obtained by means of the potential well method. [Copyright &y& Elsevier]

Abstract: C-type lectins found in many animals are non-enzymatic proteins and able to bind with mono- and oligosaccharides in a Ca2+-dependent fashion. Here, we report the cloning of two C-type lectins named BML-1 and BML-2 from the venom gland of Bungarus multicinctus, and expression of their mature peptides with 135 and 137 amino acids as inclusion bodies. Recombinant BML-1 and BML-2 proteins with 135 amino acids formed monomers, and those with 137 amino acids formed homodimers and monomers and both of them displayed certain hemagglutinating activity to rabbit erythrocytes. The results of Western blotting and immuno-affinity chromatography demonstrated that C-type lectins in B. multicinctus formed dimers in physiological conditions, and their molecular weight is lower than previous predictions. This is the first report of the cloning of the BML-2 gene from the venom gland of B. multicinctus, as well as an investigation of its confirmation and biological functions. [Copyright &y& Elsevier]

Abstract: In this paper, we shall use local estimates to give the superconvergence of high-order Galerkin finite element method for the elliptic equation of second order with constant coefficients by using the symmetric technique and integral identity. We get improved superconvergence on the inner locally symmetric mesh with respect to a point x 0 for rectangular and triangular meshes. [Copyright &y& Elsevier]

Abstract: In terms of stress and displacement, the linear elasticity problem is discretized by a least-squares finite element method. In the case of a convex polygonal domain, the stress is approximated by the lowest-order Raviart–Thomas–Nédélec flux element, and the displacement by the linear C0 element. We obtain coerciveness and optimal H1, L2 and H(div)-error bounds, uniform in Lamé constant λ, for displacement and stress, respectively. Our method also allows the use of any other combination of conforming elements for stress and displacement, e.g., C0 elements for all variables. [Copyright &y& Elsevier]

In this paper, we consider the solution of the biharmonic equation using Adini nonconforming finite element, and report new results of the asymptotic error expansions of the interpolation error functionals and nonconforming remainder. These expansions are used to develop two extrapolation formulas and a series of sharp error estimates. Finally, the numerical results have verified the extrapolation theory. [ABSTRACT FROM AUTHOR]