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This study primarily investigates advanced object detection and time series prediction methods in image-based visual servoing systems, aiming to capture targets better and predict the motion trajectory of robotic arms in advance, thereby enhancing the system's performance and reliability. The research first implements object detection on the VOC2007 dataset using the Detection Transformer (DETR) and achieves ideal detection scores. The particle swarm optimization algorithm and 3-5-3 polynomial interpolation methods were utilized for trajectory planning, creating a unique dataset through simulation. This dataset contains randomly generated trajectories within the workspace, fully simulating actual working conditions. Significantly, the Bidirectional Long Short-Term Memory (BILSTM) model was improved by substituting its traditional Multilayer Perceptron (MLP) components with Kolmogorov–Arnold Networks (KANs). KANs, inspired by the K-A theorem, improve the network representation ability by placing learnable activation functions on fixed node activation functions. By implementing KANs, the model enhances parameter efficiency and interpretability, thus addressing the typical challenges of MLPs, such as the high parameter count and lack of transparency. The experiments achieved favorable predictive results, indicating that the KAN not only reduces the complexity of the model but also improves learning efficiency and prediction accuracy in dynamic visual servoing environments. Finally, Gazebo software was used in ROS to model and simulate the robotic arm, verify the effectiveness of the algorithm, and achieve visual servoing. [ABSTRACT FROM AUTHOR]

In this paper, a numerical framework for modelling multiphase flows with interface correction is proposed. In original Volume-of-Fluid method, the interface smearing may appear since the interface profile deviates from its equilibrium state, especially in the simulations of complex interface deformation. To solve this problem, a novel correction step is introduced into the procedure after solving the volume fraction transport equation, and this step just works on the region of phase interface. The difference between the current method and the previous work is that the correction coefficient can be adjusted adaptively with the gradient of normal velocity at the interface, which is strongly correlated to the intensity of interface smearing and changes with the computational time and interface position. The validation computations are performed for bubble deformation (initial shapes of two-dimensional four-lobed-star and three-dimensional (3D) box with holes), bubble rising in a channel and Rayleigh–Taylor instability problems (Reynolds number of 100 and 1000). The obtained results show that the unphysical phenomenon of interface smearing is suppressed effectively, and the interface sharpness is improved greatly by the present method. In addition, the mass of bubble deformation by the original method will decrease by 13.3%. While these results obtained by the present method are in good agreement with the analytical solutions or published data. [ABSTRACT FROM AUTHOR]

This article study the following on p-Kirchhoff modified Schrödinger equation with critical nonlinearity in R N : K (u) + V (x) | u | p - 2 u = λ ∫ R N | u (y) | 2 p μ ∗ | y - x | μ d y | u (x) | 2 p μ ∗ - 2 u (x) + f (x , u) in R N , where K (u) = - a + b ∫ R N | ∇ u | p d x Δ p u - a u Δ p (u 2) with a > 0 , b ≥ 0 , 0 < μ < N , N ≥ 3 , and λ > 0 is a positive parameter. Here p μ ∗ : = p 2 2 N - μ N - p is the critical exponent with respect to the Hardy–Littlewood–Sobolev inequality. First, we establish the concentration-compactness principle related to our problem. Moreover, under some suitable assumptions on the nonlinearity f and the potential V, the existence of infinitely many nontrivial solutions are obtained by using the concentration-compactness principle and the symmetric mountain pass theorem. We generalize and fill in some of the previous results (Liang et al., Math Methods Appl Sci 43:2473–2490, 2020; Liang and Song, Differ Integral Equ 35:359–370, 2022; Yang and Ding, Ann Mat Pura Appl 192:783–804, 2013). [ABSTRACT FROM AUTHOR]

In the implementation of robot motion control, complex kinematic computations consume too much central processing unit (CPU) time and affect the responsiveness of robot motion. To solve this problem, this paper proposes a parallel method for solving kinematic equations of articulated robots based on the coordinate rotation digital computer (CORDIC) algorithm. The method completes the fast calculation of the transcendental function based on the CORDIC algorithm, adopts the tree structure method to optimize the key computational paths of forward and inverse solutions, and designs a parallel pipeline to realize the low latency and high throughput of the kinematic equations. The experiments of the proposed method are validated based on the field-programmable gate array (FPGA) hardware experimental platform, and the experimental results demonstrate that the computational time to complete the entire kinematic equations is 4.68 μs, of which the computational time for the kinematic positive solution is 0.52 μs and the computational time for the kinematic inverse solution is 4.16 μs. [ABSTRACT FROM AUTHOR]

To design a class of full cover trajectories that satisfy curvature limitations and enhance the buckling load of constructed laminates, a variable stiffness laminate is proposed by applying the cubic Ferguson curve. First, the traditional explicit form of the cubic Ferguson curve is redefined as polar coordinates, two connected Ferguson curve segments with three extra parameters are applied to describe full cover trajectories, and the effects on trajectories introduced by these modifications are discussed. Then, the finite element method is used to introduce parameters for analyzing the buckling load of the designed variable stiffness laminates. Numerical experiments show that automatic fiber placement (AFP) trajectories described by the cubic Ferguson curve can automatically reach C 1 continuity and can be locally modified by adjusting the introduced parameters. Compared with traditional constant stiffness laminates, the variable stiffness laminates designed using the proposed method exhibit a higher buckling load and better stability. [ABSTRACT FROM AUTHOR]

This paper studies a method for high-precision acquisition of position signals for permanent magnet direct drive servo motors at low speed. First of all, the problem of poor position feedback accuracy and sensor feedback delay in the low-speed operation of the permanent magnet direct drive servo motor is analyzed. Secondly, through analysis and simulation, it is found that the interpolation method can play a certain role in compensating the rotor position signal. However, when the speed is close to 0, the output signal of the sensor will fluctuate in a short time, which will affect the speed control accuracy. Therefore, this paper uses the observer method to achieve high-precision acquisition of the position signal of the permanent magnet direct drive servo motor at low speed. The observer method adopts the idea of combining the system model and closed-loop control. Additionally, it makes full use of the parameter information of the motor system. The control performance of the motor can be better guaranteed through the design of the observer parameters and the accuracy of the rotor position estimation result has been greatly improved. Finally, an experimental platform for permanent magnet direct drive servo motors is built, and the rotor position signal acquisition method based on the observer method is verified to have good performance through simulation and experiments. Not only the accuracy of the rotor position estimation result is improved, but also the motor control performance is improved, realizing the stable operation of the permanent magnet direct drive servo motor at low speed. [ABSTRACT FROM AUTHOR]

In this paper, we consider a critical (p, q) equation on the Heisenberg group of the following form: - Δ H , p u - Δ H , q u + V (ξ) (| u | p - 2 u + | u | q - 2 u) = μ ∫ H n F (ξ , u) | η - 1 ξ | λ d ξ f (η , u) + | u | q ∗ - 2 u , where the operator - Δ H , ℘ φ = div H (| D H φ | H ℘ - 2 D H φ) , with ℘ ∈ { p , q } , is the proverbial horizontal ℘ -Laplacian on the Heisenberg group, 1 < p < (2 Q - λ) 2 Q q < q < Q , q ∗ = q Q / (Q - q) is the critical exponent, and Q = 2 n + 2 is the homogeneous dimension of H n , μ and λ are some real parameters. Under the appropriate assumptions of potential functions V and f, the existence of entire solutions to the above equation on the Heisenberg group is obtained by using the mountain pass theorem and the concentration compactness principle. The results presented here extend or complete recent papers and are new to critical equations involving (p, q)-Laplacian operators and convolution terms on Heisenberg group. [ABSTRACT FROM AUTHOR]

Heat shock proteins (HSPs) play critical roles in regulating different mechanisms under high-temperature conditions. HSPs have been identified and well-studied in different plants. However, there is a lack of information about their genomic organization and roles in medicinal plants and fungi, especially in Wolfi-poria cocos (W. cocos). We identified sixteen heat shock proteins (HSPs) in W. cocos and analyzed in terms of phylogenetic analysis, gene structure, motif distribution patterns, physiochemical properties, and expression comparison in different strains. Based on phylogenetic analysis, HSPs were divided into five subgroups (WcHSP100, WcHSP90, WcHSP70, WcHSP60, and WcsHSP). Subgroups WcHSP100s, WcHSP90s, WcHSP70s, WcHSP60, and WcsHSPs were further divided into 3, 2, 3, 1, and 6 subfamilies, respectively. Moreover, the expression profiling of all HSP genes in five strains of W. cocos under different temperature extremes revealed that expression of most HSPs were induced by high temperature. However, every subfamily showed different expression suggesting distinctive role in heat stress tolerance. WcHSP70-4, WcHSP90-1, and WcHSP100-1 showed the highest response to high temperature stress. Heterologous expression of WcHSP70-4, WcHSP90-1, and WcHSP100-1 genes in Escherichia coli enhanced survival rate of E. coli during heat stress. These findings suggest the role of W. cocos heat shock genes in the high temperature stress tolerance. [ABSTRACT FROM AUTHOR]

Key Clinical Messase: Periungual warts are frequently encountered in the field of dermatology. Here, we describe the case of a 69‐year‐old individual who presented with hand warts. The wart growth extended to the finger stump, resulting in a soft tissue defect on the fingertip of the right thumb. A treatment approach involving superficial x‐ray therapy in combination with tretinoin was employed to address this finding. The warts disappeared after completing 26 days of the treatment regimen. Fingertip soft tissue defects due to periungual warts are a rare occurrence in clinical settings. This report serves as the first documented case of such a problem successfully managed with the treatment approach mentioned above. [ABSTRACT FROM AUTHOR]

With the advancement of global economic integration, traditional trade barriers have been greatly reduced, and the marginal utility of tariff reductions on trade expansion has become weaker and weaker. Especially under the global value chain division of labor system, intermediate products and parts have undergone multiple cross-border trades. The cumbersome trade procedures will greatly increase trade costs and destroy the driving force of trade. After improving infrastructure and optimizing customs clearance procedures, with the improvement of convenience, more countries and enterprises can participate in the global division of labor. Considering the industry characteristics of high-tech manufacturing, this paper selects panel data of high-tech manufacturing from multiple sample countries and uses the panel data two-way fixed-effect model to empirically analyze the impact of a country's trade facilitation level on the global value chain of high-tech manufacturing in a country. From the perspective of global value chain status, the improvement of a country's level of trade facilitation can significantly promote the country's high-tech manufacturing global value chain status. The level of foreign direct investment, the degree of opening to the outside world, the level of government public services, the level of human capital, and the R&D capability are all significantly positive at the 1% level, while the level of physical capital is significantly negative at the 1% level. [ABSTRACT FROM AUTHOR]

There are multiple treatment modalities for periungual warts (PWs), although most are destructive and painful, limiting their application. Radiotherapy is a non‐invasive method suitable for treating PW patients with contraindications to invasive procedures. To investigate the efficacy and safety of topical Tretinoin combined with Superficial X‐ray therapy (SXRT) in treating PWs. This study included patients with 65 PWs who underwent treatment and a 3‐month follow‐up. Twenty four PWs were subjected to SXRT alone (group A). The remaining 41 PWs were subjected to SXRT combined with the application of the Tretinoin cream from the first day (group B). The overall clinical response rate, recurrence rates, cosmetic outcomes, and adverse events were observed during the follow‐up period. The complete clearance rate (75% vs. 92.7% in groups A and B, respectively) and healing times (19.9 vs. 16.0 days in groups A and B, respectively) between the two groups were significantly different (p < 0.046 and 0.04), indicating the combination treatment is more effective. Notably, there was no damaging or permanent deformation on the nail, and the other adverse effects were mild and bearable. Topical Tretinoin combined with SXRT therapy is an effective strategy for treating PWs, with minor side effects. It is painless and with excellent cosmetic outcomes. [ABSTRACT FROM AUTHOR]

This paper is concerned with a class of nonlocal Schrödinger‐Poisson type system with sublinear term. With the aid of the Ekeland's variational principle and the mountain pass theorem, the existence of negative energy solution, positive energy solution, and positive ground state solution is obtained, respectively. Moreover, we also obtain the multiplicity of solutions by using the Clark theorem. The novelty of this paper is that the equation has not only nonlocal term but also nonlocal coefficient. [ABSTRACT FROM AUTHOR]

Summary: Transactional data structures support threads executing a sequence of operations atomically. Dynamic transactions allow operands to be generated on the fly and allows threads to execute code in between the operations of a transaction, in contrast to static transactions which need to know the operands in advance. A framework called lock‐free transactional transformation (LFTT) allows data structures to run high‐performance transactions, but it only supports static transactions. We present dynamic transactional transformation, an extension to LFTT to add support for dynamic transactions and wait‐free progress while retaining its speed. The thread‐helping scheme of LFTT presents a unique challenge to dynamic transactions. We overcome this challenge by changing the input of LFTT from a list of operations to a function, forcing helping threads to always start at the beginning of the transaction, and allowing threads to skip completed operations through the use of a list of return values. We thoroughly evaluate the performance impact of support for dynamic transactions and wait‐free progress and find that these features do not hurt the performance of LFTT for our test cases. [ABSTRACT FROM AUTHOR]

To study the cyclic behavior of partially precast steel fiber high-strength concrete columns with high-strength steel bars, four full-sized square column specimens were fabricated and tested under constant axial load and horizontal cyclic load. The effects of the strength of precast concrete shell and the diameter of cast-in-place column core were analyzed in detail. The results show that partially precast steel fiber high-strength concrete columns have good seismic performance and deformation ability. Compared to the concrete column with lower strength of precast concrete shell, the concrete column with higher strength of precast concrete shell showed higher bearing capacity and energy dissipation capacity while lower ductility. Moreover, with the increase of the diameter of cast-in-place column core, the bearing capacity and the deformation ability of the specimen decreased. Finally, based on the experimental research and theoretical analysis, a calculation model for predicting the maximum bearing capacity was proposed, and the results obtained from the formulas were in good agreement with those from the experiments. [ABSTRACT FROM AUTHOR]

Biofilms are a form of microbial community that can be beneficial for industrial fermentation because of their remarkable environmental resistance. However, the mechanism of biofilm formation in Saccharomyces cerevisiae remains to be fully explored, and this may enable improved industrial applications for this organism. Although quorum-sensing (QS) molecules are known to be involved in bacteria biofilm formation, few studies have been undertaken with these in fungi. 2-phenylethanol (2-PE) is considered a QS molecule in S. cerevisiae. Here, we found that exogenous 2-PE could stimulate biofilm formation at low cell concentrations. ARO8p and ARO9p are responsible for the synthesis of 2-PE and were crucial to the formation of biofilm. Deletion of the ARO8 and ARO9 genes reduced the content of 2-PE in the early stage of fermentation, reduced ethanol yield and decreased biofilm formation. The expression of FLOp, which is involved in cell adhesion, and the content of extracellular polysaccharides of mutant strains ΔARO8 and ΔARO9 were also significantly reduced. These findings indicate that the production of 2-PE had a positive effect on biofilm formation in S. cerevisiae, thereby providing further key details for studying the formation of biofilm mechanism in the future. Key points: • Quorum-sensing molecule 2-PE positively affects biofilm formation in S. cerevisiae. • 2-PE synthetic genes ARO8 and ARO9 deletion reduced extracellular polysaccharide. • ARO8 and ARO9 deletion reduced the gene expression of the FLO family. [ABSTRACT FROM AUTHOR]

This article attempts to establish Choquet integral Jensen's inequality for set-valued and fuzzy set-valued functions. As a basis, the existing real-valued and set-valued Choquet integrals for set-valued functions are generalized, such that the range of the integrand is extended from P 0 (R +) to P 0 (R) , the upper and lower Choquet integrals are defined, and the fuzzy set-valued Choquet integral is introduced. Then Jensen's inequalities for these Choquet integrals are proved. These include reverse Jensen's inequality for nonnegative real-valued functions, real-valued Choquet integral Jensen's inequalities for set-valued functions, and two families of set-valued and fuzzy set-valued Choquet integral Jensen's inequalities. One is that the related convex function is set-valued or fuzzy set-valued, and the integrand is real-valued, the other is that the related convex function is real-valued, and the integrand is set-valued or fuzzy set-valued. The obtained results generalize earlier works (Costa in Fuzzy Sets Syst 327:31–47, 2017; Zhang et al. in Fuzzy Sets Syst 404:178–204, 2021). [ABSTRACT FROM AUTHOR]

Covalent functionalization of hexagonal boron nitride nanosheets (BNNSs) is very challenging because of their surface inactivity. In this work, a simple reductive activation method is reported to covalently decorate BNNSs with polymers. BNNSs are initially negatively charged through effective reductive treatment and subsequently reacted with bromine‐terminated poly(methyl methacrylate) chains bearing different molecular weights to obtain a series of polymer‐grafted BNNSs, which greatly enhances their compatibility and dispersibility within acetone. With the increase of the molecular weight, grafting ratio and the density of grafted chains on BNNS surfaces show decreasing trends due to steric hinderance. Addition of functionalized BNNSs at a low filler content significantly improves reinforcement performance for polymer composites. The functionalization via the reduction treatment represents a novel and versatile route to anchor a range of functionalized species to manipulate surface chemistry toward the production of functional BNNSs for broad applications. [ABSTRACT FROM AUTHOR]

Biofilm-based fermentation, as a new immobilisation strategy, is beneficial for industrial fermentation due to its excellent environmental resistance, high productivity and continuous fermentation relative to calcium alginate-immobilised fermentation. These two techniques differ mainly regarding cell stages. Here, we describe the cell phenotype of Saccharomyces cerevisiae biofilm-based fermentation and compare cell cycle stages with those during immobilisation in calcium alginate. Most cells in the biofilm-based fermentation adhered to the cotton-fibre carrier of the biofilm and were in the G2/M phase whereas alginate-embedded cells were in the G1/G0 phase. Deletion of the RIM15 gene, which regulates cell cycle progression according to nutritional status, hampered the cell cycle arrest observed in alginate-embedded cells, enhanced biofilm formation and improved fermentation ability. The improved biofilm formation shown by the rim15△ strain could be attributed to an increase in the expression level of the adhesion protein FLO11 and synthesis of trehalose. These findings suggest that the extracellular environment is mainly responsible for the difference between biofilm-based fermentation and alginate-embedded fermentation, and that RIM15 plays an essential role in cell cycle progression. Key points: • In the biofilm, S. cerevisiae cell populations were mostly in the G2/M phase while alginate-embedded cells were arrested in the G1/G0 phase. • The RIM15 gene partially influenced the cell cycle progression observed during ethanol fermentation. • Biofilm-based cells were actively adsorbed on the physical carrier. • Biofilm immobilisation could maintain cell division activity explaining its fermentation efficiency. [ABSTRACT FROM AUTHOR]

The development of melanoma may involve long non-coding RNAs (lncRNAs); however, the functions of the majority of lncRNAs in melanoma are unknown. The present study investigated the role of long intergenic non-protein coding RNA p53 induced transcript (LINC-PINT) in melanoma. In the present study, quantitative PCR was used to detect gene expression, overexpression experiments were performed to analyze gene interactions and CCK-8 assays were used to analyze cell proliferation. LINC-PINT was downregulated, while BRAF-activated non-coding RNA (BANCR) was upregulated in melanoma tissues compared with normal adjacent tissues. Expression levels of LINC-PINT decreased, while expression levels of BANCR increased with increasing tumor thickness. The expression levels of LINC-PINT and BANCR were inversely associated in melanoma tissues but not in healthy adjacent tissue. LINC-PINT overexpression downregulated BANCR expression in melanoma cells, while BANCR overexpression did not significantly affect LINC-PINT expression. LINC-PINT overexpression inhibited melanoma cell proliferation in vitro compared to controls. BANCR overexpression attenuated the effects of LINC-PINT overexpression. The present study revealed that lncRNA LINC-PINT is downregulated in melanoma and may regulate melanoma cell proliferation by downregulating lncRNA BANCR. [ABSTRACT FROM AUTHOR]

Purpose: The present study was carried out to confirm the protective effect of extract of Ginkgo biloba (Ginaton) against ischemic neuronal damage post-treatment at 24 h after reperfusion in rats with middle cerebral artery occlusion (MCAO) and further reveal its possible mechanisms. Methods: Adult male Sprague-Dawley rats were modeled by MCAO for 2 h. The rats were divided into three groups: sham, model, and Ginaton (50 mg/kg). All animals received treatment once a day for 14 days from 24 h after reperfusion. Modified neurological severity score test was performed in 1, 7 and 14 days after MCAO, and beam walking test was performed only 14 days after MCAO. Hematoxylin-eosin straining was implemented to measure infarct volume and immunohistochemical analysis was performed to calculate the number of neurons in ischemic cortex penumbra. Western blot was used to evaluate the expression of autophagy (Beclin1, LC3, AMPK, mTOR, ULK), mitochondrial dynamic protein (Parkin, DRP1, OPA1) and apoptosis (Bcl-2, Bax). Results: Post-treatment with Ginaton for 14 days decreased neurological deficit score, promoted the recovery of motor function, and noticeably reduced infarct size. Besides, Ginaton also alleviated the loss of NeuN-positive cells in ischemic cortex penumbra. In ischemic cortex, Ginaton increased the expression of Beclin1 and LC3-Ⅱ, elevated the AMPK, mTOR and ULK1, and induced autophagy. Moreover, Ginaton treatment upregulated Parkin, DRP1, and OPA1, and elevated the ratio of Bcl-2/Bax in 14 days after MCAO reperfusion injury. Conclusion: Ginaton exhibited obvious neuroprotective effects in MCAO rats with initial administered 24 h after MCAO. The mechanism of Ginaton included induction of autophagy via activation of the AMPK pathway, maintenance of mitochondrial homeostasis and inhibition of apoptosis. [ABSTRACT FROM AUTHOR]

The throughput of concurrent priority queues is pivotal to multiprocessor applications such as discrete event simulation, best-first search and task scheduling. Existing lock-free priority queues are mostly based on skiplists, which probabilistically create shortcuts in an ordered list for fast insertion of elements. The use of skiplists eliminates the need of global rebalancing in balanced search trees and ensures logarithmic sequential search time on average, but the worst-case performance is linear with respect to the input size. In this paper, we propose a quiescently consistent lock-free priority queue based on a multi-dimensional list that guarantees worst-case search time of \mathcal O(\log N) for key universe of size $N$ . The novel multi-dimensional list (MDList) is composed of nodes that contain multiple links to child nodes arranged by their dimensionality. The insertion operation works by first injectively mapping the scalar key to a high-dimensional vector, then uniquely locating the target position by using the vector as coordinates. Nodes in MDList are ordered by their coordinate prefixes and the ordering property of the data structure is readily maintained during insertion without rebalancing nor randomization. In our experimental evaluation using a micro-benchmark, our priority queue achieves an average of $50$ percent speedup over the state of the art approaches under high concurrency. [ABSTRACT FROM PUBLISHER]

We present a scalable lock algorithm and an adaptive scheme for shared-memory multiprocessors addressing the resource allocation problem, which is also known as the $$h$$ -out-of- $$k$$ mutual exclusion problem. In this problem, threads compete for $$k$$ shared resources where a thread may request an arbitrary number $$1\le h\le k$$ of resources at the same time. The challenge is for each thread to acquire exclusive access to desired resources while preventing deadlock or starvation. Many existing approaches solve this problem in a distributed system, but the explicit message passing paradigm they adopt is not optimal for shared-memory. Other applicable methods, like two-phase locking and resource hierarchy, suffer from performance degradation under heavy contention, while lacking a desirable fairness guarantee. This work describes the first multi-resource lock algorithm that guarantees the strongest first-in, first-out fairness. Our methodology is based on a non-blocking queue where competing threads spin on previous conflicting resource requests. In our experimental evaluation we compared the overhead and scalability of our lock to the best available alternative approaches using a micro-benchmark. As contention increases, our multi-resource lock obtains an average of eight times speed-up over the alternatives including GNU C++'s lock method, Boost's lock function, and Intel TBB's queue mutex. To further improve the performance on low levels of contention, we introduce an adaptive scheme that is composed of two different lock algorithms and alternates the use the locks depending on the level of contention. Our experimental results show that the composite adaptive scheme achieves the best overall performance comparing with using either lock alone when system contention is not known a priori. [ABSTRACT FROM AUTHOR]

Background: The heat shock response (HSR) is an ancient and highly conserved program of stress-induced gene expression, aimed at reestablishing protein homeostasis to preserve cellular fitness. Cells that fail to activate or maintain this protective response are hypersensitive to proteotoxic stress. The HSR is mediated by the heat shock transcription factor 1 (HSF1), which binds to conserved heat shock elements (HSE) in the promoter region of heat shock genes, resulting in the expression of heat shock proteins (HSP). Recently, we observed that hyperactivation of RhoA conditions cardiomyocytes for the cardiac arrhythmia atrial fibrillation. Also, the HSR is annihilated in atrial fibrillation, and induction of HSR mitigates sensitization of cells to this disease. Therefore, we hypothesized active RhoA to suppress the HSR resulting in sensitization of cells for proteotoxic stimuli. Methods and Results: Stimulation of RhoA activity significantly suppressed the proteotoxic stress-induced HSR in HL-1 atrial cardiomyocytes as determined with a luciferase reporter construct driven by the HSF1 regulated human HSP70 (HSPA1A) promoter and HSP protein expression by Western Blot analysis. Inversely, RhoA inhibition boosted the proteotoxic stress-induced HSR. While active RhoA did not preclude HSF1 nuclear accumulation, phosphorylation, acetylation, or sumoylation, it did impair binding of HSF1 to the hsp genes promoter element HSE. Impaired binding results in suppression of HSP expression and sensitized cells to proteotoxic stress. Conclusion: These results reveal that active RhoA negatively regulates the HSR via attenuation of the HSF1-HSE binding and thus may play a role in sensitizing cells to proteotoxic stimuli. [ABSTRACT FROM AUTHOR]

The design of high-performance computing architectures requires performance analysis of large-scale parallel applications to derive various parameters concerning hardware design and software development. The process of performance analysis and benchmarking an application can be done in several ways with varying degrees of fidelity. One of the most cost-effective ways is to do a coarse-grained study of large-scale parallel applications through the use of program skeletons. The concept of a “program skeleton” that we discuss in this article is an abstracted program that is derived from a larger program where source code that is determined to be irrelevant is removed for the purposes of the skeleton. In this work, we develop a semiautomatic approach for extracting program skeletons based on compiler program analysis. We demonstrate correctness of our skeleton extraction process by comparing details from communication traces, as well as show the performance speedup of using skeletons by running simulations in the SST/macro simulator. [ABSTRACT FROM AUTHOR]

The article offers information on the role of integrative bioinformatics pipeline in genetic identification of novel porcine microRNA genes. Topics discussed include approaches to extract candidate miRNA genes by homology technique, discovery of candidate miRNA genes by ab initio approaches and prediction of miRNA targets in pig. Also mentions about characteristical analysis of miRNA genes.

Although functionally similar proteins across species have been widely studied, functionally similar proteins within species showing low sequence similarity have not been examined in detail. Identification of these proteins is of significant importance for understanding biological functions, evolution of protein families, progression of co-evolution, and convergent evolution and others which cannot be obtained by detection of functionally similar proteins across species. Here, we explored a method of detecting functionally similar proteins within species based on graph theory. After denoting protein-protein interaction networks using graphs, we split the graphs into subgraphs using the 1-hop method. Proteins with functional similarities in a species were detected using a method of modified shortest path to compare these subgraphs and to find the eligible optimal results. Using seven protein-protein interaction networks and this method, some functionally similar proteins with low sequence similarity that cannot detected by sequence alignment were identified. By analyzing the results, we found that, sometimes, it is difficult to separate homologous from convergent evolution. Evaluation of the performance of our method by gene ontology term overlap showed that the precision of our method was excellent. Proteins 2012; © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Recently, three independent laboratories reported the generation of induced pluripotent stem cells (iPSCs) from pig (Sus scrofa). This finding sums to the growing list of species (mouse, human, monkey, and rat, in this order) for which successful reprogramming using exogenous factors has been achieved, and multiple others are possibly forthcoming. But apart from demonstrating the universality of the network identified by Shinya Yamanaka, what makes the porcine model so special? On one side, pigs are an agricultural commodity and have an easy and affordable maintenance compared with nonhuman primates that normally need to be imported. On the other side, resemblance (for example, size of organs) of porcine and human physiology is striking and because pigs are a regular source of food the ethical concerns that still remain in monkeys are not applicable. Besides, the prolonged lifespan of pigs compared with other domestic species can allow exhaustive follow up of side effects after transplantation. Porcine iPSCs may thus fill the gap between the mouse model, which due to its ease is preferred for mechanistic studies, and the first clinical trials using iPSCs in humans. However, although these studies are relevant and have created significant interest they face analogous problems that we discuss herein together with potential new directions. © 2010 IUBMB IUBMB Life, 62(4): 277–282, 2010 [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) and ischemic heart disease (IHD) represent the two most common clinical cardiac diseases, characterized by angina, arrhythmia, myocardial damage, and cardiac dysfunction, significantly contributing to cardiovascular morbidity and mortality and posing a heavy socio-economic burden on society worldwide. Current treatments of these two diseases are mainly symptomatic and lack efficacy. There is thus an urgent need to develop novel therapies based on the underlying pathophysiological mechanisms. Emerging evidence indicates that oxidative DNA damage might be a major underlying mechanism that promotes a variety of cardiac diseases, including AF and IHD. Antioxidants, nicotinamide adenine dinucleotide (NAD+) boosters, and enzymes involved in oxidative DNA repair processes have been shown to attenuate oxidative damage to DNA, making them potential therapeutic targets for AF and IHD. In this review, we first summarize the main molecular mechanisms responsible for oxidative DNA damage and repair both in nuclei and mitochondria, then describe the effects of oxidative DNA damage on the development of AF and IHD, and finally discuss potential targets for oxidative DNA repair-based therapeutic approaches for these two cardiac diseases. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF), the most common, progressive tachyarrhythmia is associated with serious complications, such as stroke and heart failure. Early recognition of AF, essential to prevent disease progression and therapy failure, is hampered by the lack of accurate diagnostic serum biomarkers to identify the AF stage. As we previously showed mitochondrial dysfunction to drive experimental and human AF, we evaluated whether cell-free circulating mitochondrial DNA (cfc-mtDNA) represents a potential serum marker. Therefore, the levels of two mtDNA genes, COX3 and ND1, were measured in 84 control patients (C), 59 patients undergoing cardiac surgery without a history of AF (SR), 100 paroxysmal (PAF), 116 persistent (PeAF), and 20 longstanding-persistent (LS-PeAF) AF patients undergoing either cardiac surgery or AF treatment (electrical cardioversion or pulmonary vein isolation). Cfc-mtDNA levels were significantly increased in PAF patients undergoing AF treatment, especially in males and patients with AF recurrence after AF treatment. In PeAF and LS-PeAF, cfc-mtDNA levels gradually decreased. Importantly, cfc-mtDNA in serum may originate from cardiomyocytes, as in vitro tachypaced cardiomyocytes release mtDNA in the medium. The findings suggest that cfc-mtDNA is associated with AF stage, especially in males, and with patients at risk for AF recurrence after treatment. [ABSTRACT FROM AUTHOR]

Cardiac disease is still the leading cause of morbidity and mortality worldwide, despite some exciting and innovative improvements in clinical management. In particular, atrial fibrillation (AF) and heart failure show a steep increase in incidence and healthcare costs due to the ageing population. Although research revealed novel insights in pathways driving cardiac disease, the exact underlying mechanisms have not been uncovered so far. Emerging evidence indicates that derailed proteostasis (i.e., the homeostasis of protein expression, function and clearance) is a central component driving cardiac disease. Within proteostasis derailment, key roles for endoplasmic reticulum (ER) and mitochondrial stress have been uncovered. Here, we describe the concept of ER and mitochondrial stress and the role of interactions between the ER and mitochondria, discuss how imbalance in the interactions fuels cardiac ageing and cardiac disease (including AF), and finally assess the potential of drugs directed at conserving the interaction as an innovative therapeutic target to improve cardiac function. [ABSTRACT FROM AUTHOR]

AlthoughHepialus xiaojinensisis important as the host ofOphiocordyceps sinensis, it remains poorly known especially in genetic structure and phylogeny status. To get a better understanding of it, the complete mitochondrial genome sequence ofH. xiaojinensiswas sequenced for the first time. The genome was 15 397 bp in size and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and an AT-rich region, and the gene composition and the arrangement of which were consistent with other insects of Hepialidae. The base composition of the genome was A (41.44%), T (39.68%), C (11.52%), and G (7.36%), with an AT content of 81.13%. Moreover, we have performed phylogenetic analysis ofH. xiaojinensisand other 11 Lepidoptera species. [ABSTRACT FROM PUBLISHER]

Atrial fibrillation (AF), the most common progressive tachyarrhythmia, results in structural remodeling which impairs electrical activation of the atria, rendering them increasingly permissive to the arrhythmia. Previously, we reported on endoplasmic reticulum stress and NAD+ depletion in AF, suggesting a role for mitochondrial dysfunction in AF progression. Here, we examined mitochondrial function in experimental model systems for AF (tachypaced HL-1 atrial cardiomyocytes and Drosophila melanogaster) and validated findings in clinical AF. Tachypacing of HL-1 cardiomyocytes progressively induces mitochondrial dysfunction, evidenced by impairment of mitochondrial Ca2+-handling, upregulation of mitochondrial stress chaperones and a decrease in the mitochondrial membrane potential, respiration and ATP production. Atrial biopsies from AF patients display mitochondrial dysfunction, evidenced by aberrant ATP levels, upregulation of a mitochondrial stress chaperone and fragmentation of the mitochondrial network. The pathophysiological role of mitochondrial dysfunction is substantiated by the attenuation of AF remodeling by preventing an increased mitochondrial Ca2+-influx through partial blocking or downregulation of the mitochondrial calcium uniporter, and by SS31, a compound that improves bioenergetics in mitochondria. Together, these results show that conservation of the mitochondrial function protects against tachypacing-induced cardiomyocyte remodeling and identify this organelle as a potential novel therapeutic target. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common clinical tachyarrhythmia with a strong tendency to progress in time. AF progression is driven by derailment of protein homeostasis, which ultimately causes contractile dysfunction of the atria. Here we report that tachypacing-induced functional loss of atrial cardiomyocytes is precipitated by excessive poly(ADP)-ribose polymerase 1 (PARP1) activation in response to oxidative DNA damage. PARP1-mediated synthesis of ADP-ribose chains in turn depletes nicotinamide adenine dinucleotide (NAD+), induces further DNA damage and contractile dysfunction. Accordingly, NAD+ replenishment or PARP1 depletion precludes functional loss. Moreover, inhibition of PARP1 protects against tachypacing-induced NAD+ depletion, oxidative stress, DNA damage and contractile dysfunction in atrial cardiomyocytes and Drosophila. Consistently, cardiomyocytes of persistent AF patients show significant DNA damage, which correlates with PARP1 activity. The findings uncover a mechanism by which tachypacing impairs cardiomyocyte function and implicates PARP1 as a possible therapeutic target that may preserve cardiomyocyte function in clinical AF. Atrial fibrillation (AF) is accompanied by a detrimental loss of functional cardiomyocytes. Here, Zhang et al. show that AF-induced cardiomyocyte dysfunction is a consequence of DNA damage-mediated PARP1 activation, which leads to depletion of NAD+ and further oxidative stress and DNA damage, and identify PARP1 inhibition as a potential therapeutic strategy in the treatment of AF. [ABSTRACT FROM AUTHOR]

In this work, hydroxyl-functionalized boron nitride nanosheet (OH-BNNS) was prepared and was blended with poly(l-lactide) (PLLA) to yield PLLA/OH-BNNS nanocomposites with excellent dispersion of OH-BNNS via the interaction of carbonyl in PLLA and hydroxyl in OH-BNNS. The effects of OH-BNNS on the crystallization and melting behaviors, isothermal crystallization kinetics, macroscopic crystal morphology and crystal structure of PLLA were studied by means of various techniques. The addition of OH-BNNS nanofillers can effectively accelerate the crystallization of PLLA and enhance the nucleation density, leading to a smaller spherulite size, increased crystallinity, a more obvious crystallization peak upon cooling but weakened cold crystallization behavior upon heating. Low OH-BNNS loading can increase the relative content of α-crystal, but the relative content of less perfect α′-crystal is increased at high OH-BNNS loading due to the strong interaction between PLLA and OH-BNNS. [ABSTRACT FROM AUTHOR]

Due to ageing of the population, the incidence of cardiovascular diseases will increase in the coming years, constituting a substantial burden on health care systems. In particular, atrial fibrillation (AF) is approaching epidemic proportions. It has been identified that the derailment of proteostasis, which is characterized by the loss of homeostasis in protein biosynthesis, folding, trafficking, and clearance by protein degradation systems such as autophagy, underlies the development of common cardiac diseases. Among various safeguards within the proteostasis system, autophagy is a vital cellular process that modulates clearance of misfolded and proteotoxic proteins from cardiomyocytes. On the other hand, excessive autophagy may result in derailment of proteostasis and therefore cardiac dysfunction. Here, we review the interplay between autophagy and proteostasis in the healthy heart, discuss the imbalance between autophagy and proteostasis during cardiac diseases, including AF, and finally explore new druggable targets which may limit cardiac disease initiation and progression. [ABSTRACT FROM AUTHOR]