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Trivariate joint modeling for longitudinal count data, recurrent events, and a terminal event for family data has increased interest in medical studies. For example, families with Lynch syndrome (LS) are at high risk of developing colorectal cancer (CRC), where the number of polyps and the frequency of colonoscopy screening visits are highly associated with the risk of CRC among individuals and families. To assess how screening visits influence polyp detection, which in turn influences time to CRC, we propose a clustered trivariate joint model. The proposed model facilitates longitudinal count data that are zero‐inflated and over‐dispersed and invokes individual‐specific and family‐specific random effects to account for dependence among individuals and families. We formulate our proposed model as a latent Gaussian model to use the Bayesian estimation approach with the integrated nested Laplace approximation algorithm and evaluate its performance using simulation studies. Our trivariate joint model is applied to a series of 18 families from Newfoundland, with the occurrence of CRC taken as the terminal event, the colonoscopy screening visits as recurrent events, and the number of polyps detected at each visit as zero‐inflated count data with overdispersion. We showed that our trivariate model fits better than alternative bivariate models and that the cluster effects should not be ignored when analyzing family data. Finally, the proposed model enables us to quantify heterogeneity across families and individuals in polyp detection and CRC risk, thus helping to identify individuals and families who would benefit from more intensive screening visits. [ABSTRACT FROM AUTHOR]

Cell‐based microarrays are widely used in the fields of drug discovery and toxicology. Precise gradient generation and automated drug feeding are essential for high‐throughput screening of live cells in tiny droplets. However, most existing technologies either require sophisticated robotic equipment or cause mechanical/physiological interference with cells. Here, a heterogeneous organohydrogel is presented for automated gradient drug feeding, while ensuring minimal interference with cells. The heterogeneous organohydrogel comprises three crucial components. The bottom surface can automatically generate gradients functioning as a gradient generator, the organohydrogel bulk allows unidirectional transport of drugs without backflow, and the top surface with hydrophilic arrays can firmly anchor the cell‐based droplet array to evaluate the concentration‐dependent bioeffects of drugs accurately. Such a unique structure enables universal screening of different cell types and drugs dissolved in different solvents, requiring neither additional accessories nor arduous drug functionalization. The heterogeneous organohydrogel with unprecedented automation and non‐interference possesses the enormous potential to be a next‐generation platform for drug screening. [ABSTRACT FROM AUTHOR]

As the era of sixth-generation (6G) communications approaches, there will be an unprecedented increase in the number of wireless internet-connected devices and a sharp rise in mobile data traffic. Faced with the scarcity of spectrum resources in traditional communication networks and challenges such as rapidly establishing communications after disasters, this study leverages unmanned aerial vehicles (UAVs) to promote an integrated multi-hop communication system combining free-space optical (FSO) communication, terahertz (THz) technology, and intelligent reflecting surface (IRS). This innovative amalgamation capitalizes on the flexibility of UAVs, the deployability of IRS, and the complementary strengths of FSO and THz communications. We have developed a comprehensive channel model that includes the effects of atmospheric turbulence, attenuation, pointing errors, and angle-of-arrival (AOA) fluctuations. Furthermore, we have derived probability density functions (PDFs) and cumulative distribution functions (CDFs) for various switching techniques. Employing advanced methods such as Gaussian–Laguerre quadrature and the central limit theorem (CLT), we have calculated key performance indicators including the average outage probability, bit error rate (BER), and channel capacity. The numerical results demonstrate that IRS significantly enhances the performance of the UAV-based hybrid FSO/THz system. The research indicates that optimizing the number of IRS elements can substantially increase throughput and reliability while minimizing switching costs. Additionally, the multi-hop approach specifically addresses the line-of-sight (LoS) dependency limitations inherent in FSO and THz systems by utilizing UAVs as dynamic relay points. This strategy effectively bridges longer distances, overcoming physical and atmospheric obstacles, and ensures stable communication links even under adverse conditions. This study underscores that the enhanced multi-hop FSO/THz link is highly effective for emergency communications after disasters, addressing the challenge of scarce spectrum resources. By strategically deploying UAVs as relay points in a multi-hop configuration, the system achieves greater flexibility and resilience, making it highly suitable for critical communication scenarios where traditional networks might fail. [ABSTRACT FROM AUTHOR]

This paper presents a promising solution to address the scarcity of spectrum resources and enhance spectrum efficiency in the context of cognitive radio (CR)-based soft-switching free-space optical (FSO)/terahertz (THz) radio frequency (RF) dual-hop amplify-and-forward (AF)–non-orthogonal multiple access (ROMANO) links. The impact of maximum tolerable interference power in the primary network, transmit power in the secondary transmitter, and maximum relay transmission power on the link are thoroughly studied. The numerical results ultimately validate the effectiveness of this link in improving performance, and a comparative analysis is conducted with the without-CR scheme, highlighting the distinctive characteristics of the proposed link. [ABSTRACT FROM AUTHOR]

Tendon injury is one of the prevalent disorders of the musculoskeletal system in orthopedics and is characterized by pain and limitation of joint function. Due to the difficulty of spontaneous tendon healing, and the scar tissue and low mechanical properties that usually develops after healing. Therefore, the healing of tendon injury remains a clinical challenge. Although there are a multitude of approaches to treating tendon injury, the therapeutic effects have not been satisfactory to date. Recent studies have shown that stem cell therapy has a facilitative effect on tendon healing. In particular, tendon stem/progenitor cells (TSPCs), a type of stem cell from tendon tissue, play an important role not only in tendon development and tendon homeostasis, but also in tendon healing. Compared to other stem cells, TSPCs have the potential to spontaneously differentiate into tenocytes and express higher levels of tendon-related genes. TSPCs promote tendon healing by three mechanisms: modulating the inflammatory response, promoting tenocyte proliferation, and accelerating collagen production and balancing extracellular matrix remodeling. However, current investigations have shown that TSPCs also have a negative effect on tendon healing. For example, misdifferentiation of TSPCs leads to a "failed healing response," which in turn leads to the development of chronic tendon injury (tendinopathy). The focus of this paper is to describe the characteristics of TSPCs and tenocytes, to demonstrate the roles of TSPCs in tendon healing, while discussing the approaches used to culture and differentiate TSPCs. In addition, the limitations of TSPCs in clinical application and their potential therapeutic strategies are elucidated. [ABSTRACT FROM AUTHOR]

To determine the expression of signal transducer and activator of transcription 3 (STAT3) in patients with fragility fractures (FFs) and its effect on the biological function of osteoblasts. The study included 32 patients with FFs who were diagnosed and treated in the research group and 30 concurrent healthy individuals in the control group. We observed STAT3 mRNA expression in the patients with FFs and controls and altered STAT3 mRNA to detect changes in the proliferation, invasion, and apoptosis of osteoblasts. The patients with FFs presented higher serum STAT3 mRNA expression than the controls (P < 0.05). We plotted receiver operating characteristic curves based on the STAT3 mRNA expression and found that the area under the curve for STAT3 mRNA was 0.856 (P < 0.05). Transfection of STAT3 mRNA mimics resulted in increased STAT3 mRNA expression, inhibited cell proliferation as detected by an MTT assay, and increased apoptosis rate, which was determined using flow cytometry with human fetal osteoblastic cell line 1.19 cells. STAT3 mRNA expression was elevated in the serum of patients with FFs and can be used as a biomarker for the diagnosis of the disease. Regulating STAT3 mRNA can inhibit the proliferation and induce the osteoblasts apoptosis. [ABSTRACT FROM AUTHOR]

Tendon injury is one of the most common disorders of the musculoskeletal system, with a higher likelihood of occurrence in elderly individuals and athletes. In posthealing tendons, two undesirable consequences, tissue fibrosis and a reduction in mechanical properties, usually occur, resulting in an increased probability of rerupture or reinjury; thus, it is necessary to propose an appropriate treatment. Currently, most methods do not sufficiently modulate the tendon healing process and restore the function and structure of the injured tendon to those of a normal tendon, since there is still inadequate information about the effects of multiple cellular and other relevant signaling pathways on tendon healing and how the expression of their components is regulated. microRNAs are vital targets for promoting tendon repair and can modulate the expression of biological components in signaling pathways involved in various physiological and pathological responses. miRNAs are a type of noncoding ribonucleic acid essential for regulating processes such as cell proliferation, differentiation, migration and apoptosis; inflammatory responses; vascularization; fibrosis; and tissue repair. This article focuses on the biogenesis response of miRNAs while presenting their mechanisms in tendon healing with perspectives and suggestions. [ABSTRACT FROM AUTHOR]

Droplet arrays show great significance in biosensing and biodetection because of low sample consumption and easy operation. However, inevitable water evaporation in open environment severely limits their applications in time‐consuming reactions. Herein, inspired by the unique water retention features of leaves, it is demonstrated that an open droplet array on patterned organohydrogel surface with water evaporating replenishment (POWER) for ultrawide time‐range biosensing, which integrated hydrophilic hydrogel domains and hydrophobic organogel background. The hydrogel domains on the surface can supply water to the pinned droplets through capillary channels formed in the nether organohydrogel bulk. The organogel background can inhibit water evaporation like the wax coating of leaves. Such a unique bioinspired design enables ultrawide time‐range biosensing in open environment from a few minutes to more than five hours involving a variety of analytes such as ions, small molecules, and macromolecules. The POWER provides a feasible and open biosensing platform for ultrawide time‐range reactions. [ABSTRACT FROM AUTHOR]

Optimal control theory and reinforcement learning are gradually being used in the field of industrial control. In this article, a new optimal tracking control scheme for 160 MW boiler‐turbine systems is proposed based on an online policy iteration integral reinforcement learning (IRL) method. Firstly, a self‐learning state tracking control with a cost function is developed to deal with the optimal tracking control problems for the boiler‐turbine nonlinear system. Then with a modified cost function, a policy iteration‐based IRL method is introduced to obtain the optimal control law. Finally, the monotonicity and the convergence of the cost function is analyzed and the detailed implementation of the policy iteration‐based IRL method is provided via neural networks. The simulation results show that the control of the boiler‐turbine system can converge in a short time by using this online iterative method. Through a theoretical simulation case, it can be concluded that the proposed method is more advanced compared with the MPC method. [ABSTRACT FROM AUTHOR]

Transforming data into ciphertexts and storing them in the cloud database is a secure way to simplify data management. Public key encryption with keyword search (PEKS) is an important cryptographic primitive as it provides the ability to search for the desired files among ciphertexts. As a variant of PEKS, certificateless public key authenticated encryption with keyword search (CLPAEKS) not only simplifies certificate management but also could resist keyword guessing attacks (KGA). In this paper, we analyze the security models of two recent CLPAEKS schemes and find that they ignore the threat that, upon capturing two trapdoors, the adversary could directly compare them and distinguish whether they are generated using the same keyword. To cope with this threat, we propose an improved security model and define the notion of strong trapdoor indistinguishability. We then propose a new CLPAEKS scheme and prove it to be secure under the improved security model based on the intractability of the DBDH problem and the DDH problem in the targeted bilinear group. [ABSTRACT FROM AUTHOR]

Tendon injuries are one of the most common musculoskeletal disorders for which patients seek medical aid, reducing not only the quality of life of the patient but also imposing a significant economic burden on society. The administration of growth factors at the wound site is a feasible solution for enhancing tendon healing. Platelet-derived growth factor-BB (PDGF-BB) has a well-defined safety profile compared to other growth factors and has been approved by the Food and Drug Administration (FDA). The purpose of this review is to summarize the role of PDGF-BB in tendon healing through a comprehensive review of the published literature. Experimental studies suggest that PDGF-BB has a positive effect on tendon healing by enhancing inflammatory responses, speeding up angiogenesis, stimulating tendon cell proliferation, increasing collagen synthesis and increasing the biomechanics of the repaired tendon. PDGF-BB is regarded as a promising candidate in tendon healing. However, in order to realize its full potential, we still need to carefully consider and study key issues such as dose and application time in the future, so as to explore further applications of PDGF-BB in the tendon healing process. [ABSTRACT FROM AUTHOR]

Many complex nonlinear optimization or control issues can be transformed into the solving of time-varying nonlinear equations (TVNEs), playing a fundamental role in the control and management of complex systems. As a result, a robust and high-precision online solution method is significant for TVNE. However, there are three main challenges for handling TVNE via the existing methods: First, short-time invariance assumption frequently leveraged in the existing methods leads to lagging errors that are difficult to eliminate. Second, it is difficult in dealing with unknown noise disturbance during the solution process, which causes low solution accuracy or solution failure. Third, existing continuous-time methods are hard to be implemented on digital equipments. In this article, an anti-noise discrete-time neural dynamics (DTND) is designed and studied to overcome the above issues systematically. The theoretical analysis and numerical simulations demonstrate that the proposed model effectively eliminates the lagging errors and achieves the accurate solution of the TVNE in a noisy environment. Moreover, to verify the superior numerical computational property of the DTND model, the intention recognition of lower limbs is explored from the artificial systems, computational experiments, and parallel execution (ACP) framework. Specifically, a nonlinear artificial dynamic system (NADS) concerning the human surface electromyogram (sEMG) signals and joint information is established, which performs in parallel with the actual human lower limb physical experiments. Simulation results illustrate that, within the acceptable range of the digital computer, the controller designed by the DTND model can well guide the NADS to accurately recognize the motion intention of the human lower limb. [ABSTRACT FROM AUTHOR]

The reconstruction of large skeletal defects is still a tricky challenge in orthopedics. The newly formed bone tissue migrates sluggishly from the periphery to the center of the scaffold due to the restrictions of exchange of oxygen and nutrition impotent cells osteogenic differentiation. Angiogenesis plays an important role in bone reconstruction and more and more studies on angiogenesis in bone tissue engineering had been published. Promising advances of angiogenesis in bone tissue engineering by scaffold designs, angiogenic factor delivery, in vivo prevascularization and in vitro prevascularization are discussed in detail. Among all the angiogenesis mode, angiogenic factor delivery is the common methods of angiogenesis in bone tissue engineering and possible research directions in the future. [ABSTRACT FROM AUTHOR]

Traditional lubricant impregnated surfaces usually required fluorinated lubricants to achieve slippery oil repellency, but the lubricants infused were expensive and toxic and also suffered from limited stability because of their migrating, evaporating, and leaking during use. Herein, to address this issue, we fabricated a durably fluorine-free slippery oil-repellent hydrogel coating using water as the lubricant. Due to its enhanced water-binding affinity, water could wet the hydrogel completely and form a hydrated-water layer on the surface. The hydrated water layer could act as a lubricant to repel foreign oils, which allowed the hydrogel to display slippery oil-repellency in air, exhibit superoleophobicity underwater, and resist oil fouling upon oil immersion. The hydrogel kept its oil-repellent properties after mechanical tests as well as thermal and freezing treatments, demonstrating its durability. Thanks to its moisture absorption, the water lubricant layer could self-regenerate upon the lubricated water layer depletion through exposure to a humid environment. Exploiting it is water-attracting and oil repellency, the hydrogel coating was demonstrated as a versatile platform for oil/water separation, polymer/water separation, drag-reduction, and anti-fogging. [ABSTRACT FROM AUTHOR]

Tendon injury is a disorder of the musculoskeletal system caused by overuse or trauma, which is characterized by pain and limitations in joint function. Since tendon healing is slowly and various treatments are generally ineffective, it remains a clinically challenging problem. Recent evidences suggest that basic fibroblast growth factor (bFGF) not only plays an important role in tendon healing, but also shows a positive effect in laboratory experimentations. The purpose of this review is to summarize the effects of bFGF in the tendon healing. Firstly, during the inflammatory phase, bFGF stimulates the proliferation and differentiation of vascular endothelial cells to foster neovascularization. Furthermore, bFGF enhances the production of pro-inflammatory factors during the early phase of tendon healing, thereby accelerating the inflammatory response. Secondly, the cell proliferation phase is accompanied by the synthesis of a large number of extracellular matrix components. bFGF speeds up tendon healing by stimulating fibroblasts to secrete type III collagen. Lastly, the remodeling phase is characterized by the transition from type III collagen to type I collagen, which can be promoted by bFGF. However, excessive injection of bFGF can cause tendon adhesions as well as scar tissue formation. In future studies, we need to explore further applications of bFGF in the tendon healing process. [ABSTRACT FROM AUTHOR]

A novel event-triggered optimal tracking control (ETOTC) method is developed for discrete-time nonlinear systems in this study. For the time-invariant desired trajectory, we prove that the tracking error is asymptotically stable, and an upper bound of the real performance index can be predetermined by a design parameter. For the time-varying desired trajectory, the developed triggering condition reduces communication costs by relaxing the restriction of the asymptotic stability of the closed-loop system, and we prove that the tracking error is uniformly ultimately bounded (UUB). The developed ETOTC method entails obtaining the next state of the real system. Therefore, a parallel control approach is proposed to predict the next state by constructing a parallel system for the real system. Neural networks (NNs) and adaptive dynamic programming (ADP) techniques are utilized in the parallel control approach. Moreover, the stability analysis of the closed-loop system is shown, and the tracking error and NN weight estimation errors are proved to be UUB using the Lyapunov approach. Finally, we validate the developed ETOTC method through two simulations. [ABSTRACT FROM AUTHOR]

Tendon injuries are widespread and chronic disorders of the musculoskeletal system, frequently caused by overload of the tendons. Currently, the most common treatment for tendon injuries is "cell-free therapy", of which exosomes, which can treat a host of diseases, including immune disorders, musculoskeletal injuries and cardiovascular diseases, are one kind. Among the many sources of exosomes, adipose-derived stem cell exosomes (ASC-Exos) have better efficacy. This is attributed not only to the ease of isolation of adipose tissue, but also to the high differentiation capacity of ASCs, their greater paracrine function, and immunomodulatory capacity compared to other exosomes. ASC-Exos promote tendon repair by four mechanisms: promoting angiogenesis under hypoxic conditions, reducing the inflammatory response, promoting tendon cell migration and proliferation, and accelerating collagen synthesis, thus accelerating tendon healing. This review focuses on describing studies of preclinical experiments with various exosomes, the characteristics of ASC-Exos and their mechanisms of action in tendon healing, as well as elaborating the limitations of ASC-Exos in clinical applications. [ABSTRACT FROM AUTHOR]

Tendon injury is a common disease of the musculoskeletal system, accounting for roughly 30%–40% of sports system disorder injuries. In recent years, its incidence is increasing. Many studies have shown that low-level laser therapy (LLLT) has a significant effect on tendon repair by firstly activating cytochrome C oxidase and thus carrying out the photon absorption process, secondly acting in all the three phases of tendon repair, and finally improving tendon recovery. The repair mechanisms of LLLT are different in the three phases of tendon repair. In the inflammatory phase, LLLT mainly activates a large number of VEGF and promotes angiogenesis under hypoxia. During the proliferation phase, LLLT increases the amount of collagen type III by promoting the proliferation of fibroblasts. Throughout the remodeling phase, LLLT mainly activates M2 macrophages and downregulates inflammatory factors, thus reducing inflammatory responses. However, it should also be noted that in the final phase of tendon repair, the use of LLLT causes excessive upregulation of some growth factors, which will lead to tendon fibrosis. In summary, we need to further investigate the functions and mechanisms of LLLT in the treatment of tendon injury and to clarify the nature of LLLT for the treatment of diverse tendon injury diseases. [ABSTRACT FROM AUTHOR]

Background: The coronavirus disease 2019 (COVID-19) pandemic has posed a significant influence on public mental health. Current efforts focus on alleviating the impacts of the disease on public health and the economy, with the psychological effects due to COVID-19 relatively ignored. In this research, we are interested in exploring the quantitative characterization of the pandemic impact on public mental health by studying an online survey dataset of the United States.Methods: The analyses are conducted based on a large scale of online mental health-related survey study in the United States, conducted over 12 consecutive weeks from April 23, 2020 to July 21, 2020. We are interested in examining the risk factors that have a significant impact on mental health as well as in their estimated effects over time. We employ the multiple imputation by chained equations (MICE) method to deal with missing values and take logistic regression with the least absolute shrinkage and selection operator (Lasso) method to identify risk factors for mental health.Results: Our analysis shows that risk predictors for an individual to experience mental health issues include the pandemic situation of the State where the individual resides, age, gender, race, marital status, health conditions, the number of household members, employment status, the level of confidence of the future food affordability, availability of health insurance, mortgage status, and the information of kids enrolling in school. The effects of most of the predictors seem to change over time though the degree varies for different risk factors. The effects of risk factors, such as States and gender show noticeable change over time, whereas the factor age exhibits seemingly unchanged effects over time.Conclusions: The analysis results unveil evidence-based findings to identify the groups who are psychologically vulnerable to the COVID-19 pandemic. This study provides helpful evidence for assisting healthcare providers and policymakers to take steps for mitigating the pandemic effects on public mental health, especially in boosting public health care, improving public confidence in future food conditions, and creating more job opportunities.Trial Registration: This article does not report the results of a health care intervention on human participants. [ABSTRACT FROM AUTHOR]

Background: The coronavirus disease 2019 (COVID-19) pandemic has posed a significant influence on public mental health. Current efforts focus on alleviating the impacts of the disease on public health and the economy, with the psychological effects due to COVID-19 relatively ignored. In this research, we are interested in exploring the quantitative characterization of the pandemic impact on public mental health by studying an online survey dataset of the United States. Methods: The analyses are conducted based on a large scale of online mental health-related survey study in the United States, conducted over 12 consecutive weeks from April 23, 2020 to July 21, 2020. We are interested in examining the risk factors that have a significant impact on mental health as well as in their estimated effects over time. We employ the multiple imputation by chained equations (MICE) method to deal with missing values and take logistic regression with the least absolute shrinkage and selection operator (Lasso) method to identify risk factors for mental health. Results: Our analysis shows that risk predictors for an individual to experience mental health issues include the pandemic situation of the State where the individual resides, age, gender, race, marital status, health conditions, the number of household members, employment status, the level of confidence of the future food affordability, availability of health insurance, mortgage status, and the information of kids enrolling in school. The effects of most of the predictors seem to change over time though the degree varies for different risk factors. The effects of risk factors, such as States and gender show noticeable change over time, whereas the factor age exhibits seemingly unchanged effects over time. Conclusions: The analysis results unveil evidence-based findings to identify the groups who are psychologically vulnerable to the COVID-19 pandemic. This study provides helpful evidence for assisting healthcare providers and policymakers to take steps for mitigating the pandemic effects on public mental health, especially in boosting public health care, improving public confidence in future food conditions, and creating more job opportunities. Trial registration: This article does not report the results of a health care intervention on human participants. [ABSTRACT FROM AUTHOR]

In this article, a new self-learning parallel control method, which is based on adaptive dynamic programming (ADP) technique, is developed for solving the optimal control problem of discrete- time time-varying nonlinear systems. It aims to obtain an approximate optimal control law sequence and simultaneously guarantees the convergence of the value function. Establishing the time-varying artificial system by neural networks in a certain time-horizon, a control-sequence-improvement ADP algorithm is developed to obtain the control law sequence. For the first time, the criteria of the parallel execution are presented, such that the value function is proven to converge to a finite neighborhood of the optimal performance index function. Finally, numerical results and analysis are presented to demonstrate the effectiveness of the parallel control method. [ABSTRACT FROM AUTHOR]

The national electricity market (NEM) of Australia, operated by the Australian Energy Market Operator (AEMO), comprises five regions on the eastern coast of Australia. Together, they exhibit unique characteristics compared to most other international power systems. This stems from world-class wind and solar resources and the absence of interconnection to neighboring countries. [ABSTRACT FROM AUTHOR]

Development of advanced oil/water separation materials with durability, versatility, and cost-efficiency in a green manner is highly desired yet still challenging. Herein, to address this challenge, we fabricated an advanced platform for oil/water separation using natural corn straw as a raw material. Superhydrophobic corn straw (SHCS) blocks and filter paper with deposited SHCS powder were fabricated by one-step immersion processes that were simple and cost-efficient. The resulting corn straw-based materials kept their superhydrophobicity after immersing in oil, hand-bending test, abrasion with sandpaper, and even 120 h of UV irradiation. The SHCS block was used as an oil sorbent scaffold to absorb oils from oil/water mixtures selectively; while the SHCS powder deposited filter paper was demonstrated as a membrane to separate oil/water mixtures efficiently even in acidic, alkaline, salty, and high-temperature conditions (more than 80 °C). Importantly, these SHCS-based materials retained their high separation efficiency even after 10 cycles of oil/water separation. Superhydrophobic corn straw that can be used as a versatile platform for oil/water separation was fabricated. [ABSTRACT FROM AUTHOR]

Development of porous materials with anti-fouling and remote controllability is highly desired for oil-water separation application yet still challenging. Herein, to address this challenge, a sponge with unusual superhydrophilicity/superoleophobicity and magnetic property was fabricated through a dip-coating process. To exploit its superhydrophilic/superoleophobic property, the obtained sponge was used as a reusable water sorbent scaffold to collect water from bulk oils without absorbing any oil. Owing to its magnetic property, the sponge was manipulated remotely by a magnet without touching it directly during the whole water collection process, which could potentially lower the cost of the water collection process. Apart from acting as a water-absorbing material, the sponge can also be used as affiliation material to separate water from oil-water mixture and oil in water emulsion selectively, when fixed into a cone funnel. This research provides a key addition to the field of oil-water separation materials. [ABSTRACT FROM AUTHOR]

We have identified a switchable Prins cyclization process to form indoline‐fused tetrahydrofurans and indole‐fused oxepanes by applying different types of aldehydes under two sets of optimized conditions. Significantly, a novel Prins reaction mechanism involving an oxonium‐mediated rearrangement in the formation of five‐membered cyclic ethers is realized for the first time. [ABSTRACT FROM AUTHOR]

Development of oil-repellent coatings that are anti-fouling with water alone is highly desirable, yet still challenging. Herein, to address this challenge, we fabricate a slippery oil-repellent hydrogel coating that exhibits oil repellency when exposed in the air as well as underwater. In the air, water wets the slippery oil-repellent hydrogel coating surface completely, while organic liquid drops such as toluene can slide off the water wetted coating surface easily. When immersed in water, the slippery oil-repellent hydrogel coating surface exhibits excellent underwater superoleophobic property with all oil contact angles more than 159° and oil adhesive forces less than 1 μN. The hydrogel coating keeps its oil repellency after long-term outdoor storage, thermal treatment, knife scratching and other treatments. Exploiting its water-attracting and oil-repelling property, the slippery oil-repellent hydrogel coated copper mesh and filter paper are demonstrated as reusable membranes to separate oil–water mixtures with separation efficiency more than 97%. [ABSTRACT FROM AUTHOR]

The fast mechanical switch is one of the key devices for high-voltage direct-current circuit breakers (DCCB), and the mechanical contacts separation time determines the operating time of hybrid mechanical circuit breakers. With the increasing of the voltage and power levels of DC system, numerous technical challenges begin to emerge. For high-voltage system, the new research and the series arrangements of very fast mechanical switches include designing new drive unit to satisfy larger load mass and longer travel stroke. Aimed to reducing the peak value of electric force, a novel drive unit by using modular double capacitors has been proposed here. Based on the equivalent circuit method (ECM), the mathematical model of Thomson coil (TC) actuator which is the drive unit in fast mechanical switch is established. First, the time sequence of capacitance discharge is studied. Then, the electromagnetic force can be divided into five types in different time sequences, and the characteristics of the electromagnetic force are analysed. Finally, it is concluded that using a combination electromagnetic force with three approximate peaks can reduce the impact of the metal plate, which improve the reliability of the fast switch. [ABSTRACT FROM AUTHOR]

Human pancreatic trypsin (hPT) is an established target for acute pancreatitis (AP) therapeutics. Here, a bioinformatics protocol of protein docking, peptide refinement, dynamics simulation and affinity analysis was described to perform rational design and molecular engineering of hPT peptide aptamers. Protein docking was employed to model the intermolecular interactions between hPT and its cognate inhibitory protein, the human pancreatic trypsin inhibitor (hTI). A number of peptide fragments were cut out from the interaction sites of docked hPT-hTI complexes, from which a decapeptide fragment LNGCTLEYRP was found to exhibit potent inhibition against hPT ( K = 5.3 ± 0.8 μM). We also carried out alanine scanning and virtual mutagenesis to systematically examine the independent contribution of peptide residues to binding affinity, and the harvested knowledge were then used to guide modification and optimization of the decapeptide fragment. Subsequently, inhibition studies of nine promising candidates against recombinant hPT were conducted, from which four samples were successfully identified to have high or moderate potency ( K < 10 μM). In particular, the peptides LQVCTLEYCN and LQICTLEYCT were found to inhibit hPT activity significantly ( K = 0.23 ± 0.04 and 0.85 ± 0.18 μM, respectively). Structural analysis of hPT-peptide complex systems unraveled diverse chemical interactions such as hydrogen bonds, salt bridges and hydrophobic forces across the complex interfaces. [ABSTRACT FROM AUTHOR]

We propose an electrostatics-based placement algorithm for large-scale mixed-size circuits (ePlace-MS). ePlace-MS is generalized, flat, analytic and nonlinear. The density modeling method eDensity is extended to handle the mixed-size placement. We conduct detailed analysis on the correctness of the gradient formulation and the numerical solution, as well as the rationale of dc removal and the advantages over prior density functions. Nesterov’s method is used as the nonlinear solver, which shows high yet stable performance over mixed-size circuits. The steplength is set as the inverse of Lipschitz constant of the gradient function, while we develop a backtracking method to prevent overestimation. An approximated nonlinear preconditioner is developed to minimize the topological and physical differences between large macros and standard cells. Besides, we devise a simulated annealer to legalize the layout of macros and use a second-phase global placement to reoptimize the standard cell layout. All the above innovations are integrated into our mixed-size placement prototype ePlace-MS, which outperforms all the related works in literature with better quality and efficiency. Compared to the leading-edge mixed-size placer NTUplace3, ePlace-MS produces up to 22.98% and on average 8.22% shorter wirelength over all the 16 modern mixed-size benchmark circuits with the same runtime. [ABSTRACT FROM PUBLISHER]

Internet of Things (IoT) is playing a more and more important role after its showing up, it covers from traditional equipment to general household objects such as WSNs and RFID. With the great potential of IoT, there come all kinds of challenges. This paper focuses on the security problems among all other challenges. As IoT is built on the basis of the Internet, security problems of the Internet will also show up in IoT. And as IoT contains three layers: perception layer, transportation layer and application layer, this paper will analyze the security problems of each layer separately and try to find new problems and solutions. This paper also analyzes the cross-layer heterogeneous integration issues and security issues in detail and discusses the security issues of IoT as a whole and tries to find solutions to them. In the end, this paper compares security issues between IoT and traditional network, and discusses opening security issues of IoT. [ABSTRACT FROM AUTHOR]

Nanofiber-expanded human umbilical cord blood-derived CD34+ cell therapy has been shown to have potential applications for peripheral and myocardial ischaemic diseases. However, the efficacies of expanded CD34+ cell therapy for treating cutaneous wounds and its mechanisms of action have yet to be established. Using an excisional wound model in non-obese diabetic/severe combined immune deficient mice, we show herein that CD34+ cells accelerate the wound-healing process by enhancing collagen synthesis, and increasing fibroblast cell migration within the wound bed. Concomitantly, reduced levels of matrix metalloproteinase ( MMPs) such as MMP1, MMP3, MMP9 and MMP13 were detected in the wound beds of animals treated with CD34+ cells compared with vehicle-treated controls. CD34+ cells were found to mediate enhanced migration and proliferation of dermal fibroblast cells in vitro. Moreover, CD34+ cells secrete collagen in a serum-deprived environment. In mechanistic studies, co-culture of CD34+ cells with primary skin fibroblasts increased the expression of collagen1A1, a component of type 1 collagen, and decreased the expression of MMP1 in fibroblast cells in the presence of a proteasome inhibitor. Finally, CD34+ cell-mediated functions were transcriptionally regulated by the c-Jun N-terminal kinases pathway. Collectively, these data provide evidence of therapeutic efficacy and a novel mechanism of nanofiber-expanded CD34+ cell-mediated accelerated wound healing. [ABSTRACT FROM AUTHOR]

Vasculogenesis and angiogenesis are the major forms of blood vessel formation. Angiogenesis is the process where new vessels grow from pre-existing blood vessels, and is very important in the functional recovery of pathological conditions, such as wound healing and ischemic heart diseases. The development of better animal model and imaging technologies in past decades has greatly enriched our understanding on vasculogenesis and angiogenesis processes. Hypoxia turned out to be an important driving force for angiogenesis in various ischemic conditions. It stimulates expression of many growth factors like vascular endothelial growth factor, platelet-derived growth factor, insulin-like growth factor, and fibroblast growth factor, which play critical role in induction of angiogenesis. Other cellular components like monocytes, T cells, neutrophils, and platelets also play significant role in induction and regulation of angiogenesis. Various stem/progenitor cells also being recruited to the ischemic sites play crucial role in the angiogenesis process. Pre-clinical studies showed that stem/progenitor cells with/without combination of growth factors induce neovascularization in the ischemic tissues in various animal models. In this review, we will discuss about the fundamental factors that regulate the angiogenesis process and the use of stem cells as therapeutic regime for the treatment of ischemic diseases. [ABSTRACT FROM AUTHOR]

Innate immune system has been known to play an important role in inhibiting the malignant transformation, tumor progression and invasion. However, the mechanistic basis remains ambiguous. Despite polyclonality of human γδ T cells, Vγ2Vδ2 T cell subset was shown to recognize and limit the growth of various tumors at various degrees. The differential recognition of the tumor cells by Vγ2Vδ2 T cells are yet to be defined. Our study reveals that γδ T cells limit in vitro growth of most breast tumor cells, such as SkBr7 (HER2+), MCF7 (ER+) and MDA-MB-231 (ER−) by inhibiting their survival and inducing apoptosis, except BrCa-MZ01 (PR+) cells. To investigate detail mechanisms of antineoplastic effects, we found that cell death was associated with the surface expression levels of MICA/B and ICAM1. Molecular signaling analysis demonstrated that inhibition of cell growth by γδ T cells was associated with the lower expression levels of cell survival-related molecules such as AKT, ERK and concomitant upregulation of apoptosis-related molecules, such as PARP, cleaved caspase 3 and tumor suppressor genes PTEN and P53. However, opposite molecular signaling was observed in the resistant cell line after coculture with γδ T cells. In vivo, antineoplastic effects of γδ T cells were also documented, where tumor growth was inhibited due to the downregulation of survival signals, strong induction of apoptotic molecules, disruption of microvasculature and increased infiltration of tumor associated macrophages. These findings reveal that a complex molecular signaling is involved in γδ T cell-mediated antineoplastic effects. [ABSTRACT FROM AUTHOR]

Molecular-focused cancer therapies, e.g., molecularly targeted therapy and immunotherapy, so far demonstrate only limited efficacy in cancer patients. We hypothesize that underestimating the role of biophysical factors that impact the delivery of drugs or cytotoxic cells to the target sites (for associated preferential cytotoxicity or cell signaling modulation) may be responsible for the poor clinical outcome. Therefore, instead of focusing exclusively on the investigation of molecular mechanisms in cancer cells, convection-diffusion of cytotoxic molecules and migration of cancer-killing cells within tumor tissue should be taken into account to improve therapeutic effectiveness. To test this hypothesis, we have developed a mathematical model of the interstitial diffusion and uptake of small cytotoxic molecules secreted by T-cells, which is capable of predicting breast cancer growth inhibition as measured both in vitro and in vivo. Our analysis shows that diffusion barriers of cytotoxic molecules conspire with γδ T-cell scarcity in tissue to limit the inhibitory effects of γδ T-cells on cancer cells. This may increase the necessary ratios of γδ T-cells to cancer cells within tissue to unrealistic values for having an intended therapeutic effect, and decrease the effectiveness of the immunotherapeutic treatment. [ABSTRACT FROM AUTHOR]

Clock tree synthesis plays an important role on the total performance of chip. Gated clock tree is an effective approach to reduce the dynamic power usage. In this paper, two novel gated clock tree synthesizers, power-aware clock tree synthesizer (PACTS) and power- and slew-aware clock tree synthesizer (PSACTS), are proposed with zero skew achieved based on Elmore RC model. In PACTS, the topology of the clock tree is constructed with simultaneous buffer/gate insertion, which reduces the switched capacitance. In PSACTS, a more practical clock slew constraint is applied. Compared to previous works, clock tree synthesis is done first and followed by the insertions of clock gates. The clock slew changes a lot after the insertions of clock gates in real cases. In our work, the clock tree is constructed simultaneously with the insertions of clock gates. This ensures the limitation of the clock slew can be strictly satisfied while the limitation of the clock slew is always applied in the real design. The experimental results show that the power cost of our work is smaller and the runtime is reduced. The slew rate constraint is satisfied with a small clock skew from SPICE estimation. Generally, our work has better performance, improved efficiency and is more practical to be applied in the industry. [ABSTRACT FROM AUTHOR]