Automated bidding in computational markets: an application in market-based allocation of computing services

Autonomous agents are widely applied to automate interactions in robotics, e.g. for selling and purchasing goods on eBay, and in financial markets, e.g. in the form of quote machines and algorithmic traders. Current research investigates efficient economic mechanisms that fully automate the provisioning and usage processes of Grid-based services. On the one hand, consumers want to allocate resources on demand for their various applications, e.g. data sharing, stream processing, email, business applications and simulations. On the other hand, providers of Grid services want to govern business policies to meet their utilization and profit goals. The above-mentioned processes are not manually manageable, however, because decisions need to be taken within milliseconds. Therefore, such processes have to be automated to minimize human interactions. Hence, market mechanisms and strategic behavior play important roles when it comes to achieving automated and efficient allocation of Grid services. The paper begins by presenting a framework for automated bidding, providing a methodology for the design and implementation of configurable bidding strategies. Second, it presents a novel bidding strategy based on a reinforcement learning technique. This strategy is designed to automate the bid generation processes of consumers and providers in various market mechanisms. Third, the behavior and convergence of the strategy is evaluated in a centralized Continuous Double Auction and a decentralized on-line machine scheduling mechanism against selected benchmark bidding strategies. Fourth, we define a bidding language for communicating consumer and provider preferences to the market as well as report back the match of the market-based allocation process.     

Exogenous dsRNA Induces RNA Interference of a Chalcone Synthase Gene in Arabidopsis thaliana

Recent investigations have shown the possibility of artificial induction of RNA interference (RNAi) via plant foliar treatments with naked double-stranded RNA (dsRNA) to silence essential genes in plant fungal pathogens or to target viral RNAs. Furthermore, several studies have documented the downregulation of plant endogenous genes via external application of naked gene-specific dsRNAs and siRNAs to the plant surfaces. However, there are limited studies on the dsRNA processing and gene silencing mechanisms after external dsRNA application. Such studies would assist in the development of innovative tools for crop improvement and plant functional studies. In this study, we used exogenous gene-specific dsRNA to downregulate the gene of chalcone synthase (CHS), the key enzyme in the flavonoid/anthocyanin biosynthesis pathway, in Arabidopsis. The nonspecific NPTII-dsRNA encoding the nonrelated neomycin phosphotransferase II bacterial gene was used to treat plants in order to verify that any observed effects and processing of AtCHS mRNA were sequence specific. Using high-throughput small RNA (sRNA) sequencing, we obtained six sRNA-seq libraries for plants treated with water, AtCHS-dsRNA, or NPTII-dsRNA. After plant foliar treatments, we detected the emergence of a large number of AtCHS- and NPTII-encoding sRNAs, while there were no such sRNAs after control water treatment. Thus, the exogenous AtCHS-dsRNAs were processed into siRNAs and induced RNAi-mediated AtCHS gene silencing. The analysis showed that gene-specific sRNAs mapped to the AtCHS and NPTII genes unevenly with peak read counts at particular positions, involving primarily the sense strand, and documented a gradual decrease in read counts from 17-nt to 30-nt sRNAs. Results of the present study highlight a significant potential of exogenous dsRNAs as a promising strategy to induce RNAi-based downregulation of plant gene targets for plant management and gene functional studies.     

Aging of Vascular System Is a Complex Process: The Cornerstone Mechanisms

Aging is one of the most intriguing processes of human ontogenesis. It is associated with the development of a wide variety of diseases affecting all organs and their systems. The victory over aging is the most desired goal of scientists; however, it is hardly achievable in the foreseeable future due to the complexity and ambiguity of the process itself. All body systems age, lose their performance, and structural disorders accumulate. The cardiovascular system is no exception. And it is cardiovascular diseases that occupy a leading position as a cause of death, especially among the elderly. The aging of the cardiovascular system is well described from a mechanical point of view. Moreover, it is known that at the cellular level, a huge number of mechanisms are involved in this process, from mitochondrial dysfunction to inflammation. It is on these mechanisms, as well as the potential for taking control of the aging of the cardiovascular system, that we focused on in this review.     

Novel Models of Crohn’s Disease Pathogenesis Associated with the Occurrence of Mitochondrial Dysfunction in Intestinal Cells

Crohn’s disease remains one of the challenging problems of modern medicine, and the development of new and effective and safer treatments against it is a dynamic field of research. To make such developments possible, it is important to understand the pathologic processes underlying the onset and progression of Crohn’s disease at the molecular and cellular levels. During the recent years, the involvement of mitochondrial dysfunction and associated chronic inflammation in these processes became evident. In this review, we discuss the published works on pathogenetic models of Crohn’s disease. These models make studying the role of mitochondrial dysfunction in the disease pathogenesis possible and advances the development of novel therapies.     

Patient-specific computer modeling of blood flow in cerebral arteries with aneurysm and stent

We present the special arterial fluid mechanics techniques we have developed for patient-specific computer modeling of blood flow in cerebral arteries with aneurysm and stent. These techniques are used in conjunction with the core computational technique, which is the space?Ctime version of the variational multiscale (VMS) method and is called ??DST/SST-VMST.?? The special techniques include using NURBS for the spatial representation of the surface over which the stent mesh is built, mesh generation techniques for both the finite- and zero-thickness representations of the stent, techniques for generating refined layers of mesh near the arterial and stent surfaces, and models for representing double stent. We compute the unsteady flow patterns in the aneurysm and investigate how those patterns are influenced by the presence of single and double stents. We also compare the flow patterns obtained with the finite- and zero-thickness representations of the stent.     

Mechanochemical preparation of kaempferol intermolecular complexes for enhancing the solubility and bioavailability

Abstract

In this study, complexes of kaempferol (KF) with polysaccharide arabinogalactan (AG) and disodium glycyrrhizinate (Na₂GA) were prepared through mechanochemical technique to improve the solubility and bioavailability of KF. The physicochemical properties and the interactions of KF with AG/Na₂GA were investigated through dissolution, SEM, XRD, and DSC studies. The reduction of particle sizes and destruction of crystal forms revealed the formation of solid dispersion which may have assisted the dissolution of the drug. The accelerated stability study showed higher stability for KF–Na₂GA complex. In vivo pharmacokinetic study was performed to observe the plasma drug concentrations for KF complexes. Mechanochemical complexation of KF with AG/Na₂GA improved the pharmacological activity as evident by the inhibitory potential of the complexes towards carbohydrate metabolic enzymes. In vivo studies were performed in STZ-induced diabetic mice, where the group treated with KF–AG complex showed better liver and kidney function and lower blood glucose levels than pure KF. Therefore, mechanochemical complexes of KF with polysaccharide or glycyrrhizate may serve as a promising formulation for the treatment of diabetes.     

Job-shop like manufacturing system with variable power threshold and operations with power requirements

This paper addresses an important issue in manufacturing by considering the scheduling of a Job-shop like manufacturing system involving a power threshold that must not be exceeded over time. A power profile is attached to operations that must be scheduled. This power profile presents a consumption peak at the start of process in order to model most of real-world machining operations. These operations must be scheduled according to the instantly available power threshold. A mathematical formulation of the problem is proposed; its main goal is to minimise the total completion time of all operations. A set of instances is built based on classical format of instances for the Job-shop problem. As it is time-consuming to obtain exact solutions on these instances with the CPLEX solver, a Greedy Randomised Adaptive Search Procedure hybridised with an Evolutionary Local Search (GRASP × ELS) metaheuristic is designed. The GRASP × ELS is compared with two other metaheuristics: a Variable Neighbourhood Search and a Memetic Algorithm. The GRASP × ELS is also compared with several algorithms developed in the literature for the classical job-shop problem. Results show the relevancy of the metaheuristic approaches both in terms of computational time and quality of solutions.     

The Role of Altered Mitochondrial Metabolism in Thyroid Cancer Development and Mitochondria-Targeted Thyroid Cancer Treatment

Thyroid cancer (TC) is the most common type of endocrine malignancy. Tumour formation, progression, and metastasis greatly depend on the efficacy of mitochondria—primarily, the regulation of mitochondria-mediated apoptosis, Ca²⁺ homeostasis, dynamics, energy production, and associated reactive oxygen species generation. Recent studies have successfully confirmed the mitochondrial aetiology of thyroid carcinogenesis. In this review, we focus on the recent progress in understanding the molecular mechanisms of thyroid cancer relating to altered mitochondrial metabolism. We also discuss the repurposing of known drugs and the induction of mitochondria-mediated apoptosis as a new trend in the development of anti-TC therapy.