The generalized Kuhn model of linear viscoelasticity

We propose a generalization of the Kuhn model of linear viscoelasticity. This generalization, which has four material parameters, is able to provide a near frequency independent response over a wide range of frequencies. It is useful for highly dissipative materials such as asphalt concrete. It is derived by generalizing Lubliner and Panoskaltsis’s modified Kuhn model, but we also show that it is closely related to fractional derivative models. We show that the model admits a rheological approximation, that is, an approximation by classical springs and dashpots. The model and rheological representation are compared to experimental data.     

A model checking-based approach for security policy verification of mobile systems

This article describes an approach for the automated verification of mobile systems. Mobile systems are characterized by the explicit notion of location (e.g., sites where they run) and the ability to execute at different locations, yielding a number of security issues. To this aim, we formalize mobile systems as Labeled Kripke Structures, encapsulating the notion of location net that describes the hierarchical nesting of the threads constituting the system. Then, we formalize a generic security-policy specification language that includes rules for expressing and manipulating the code location. In contrast to many other approaches, our technique supports both access control and information flow specification. We developed a prototype framework for model checking of mobile systems. It works directly on the program code (in contrast to most traditional process-algebraic approaches that can model only limited details of mobile systems) and uses abstraction-refinement techniques, based also on location abstractions, to manage the program state space. We experimented with a number of mobile code benchmarks by verifying various security policies. The experimental results demonstrate the validity of the proposed mobile system modeling and policy specification formalisms and highlight the advantages of the model checking-based approach, which combines the validation of security properties with other checks, such as the validation of buffer overflows.     

Pipe production and consumption

The reconstruction of metallurgical enterprises between 2002–2013 to improve pipe competitive-ness is surveyed. The performance of pipe manufacturers between 2010 and 2014 is analyzed.     

Cancer Cell Response to Anthracyclines Effects: Mysteries of the Hidden Proteins Associated with These Drugs

A comprehensive proteome map of T-lymphoblastic leukemia cells and its alterations after daunorubicin, doxorubicin and mitoxantrone treatments was monitored and evaluated either by paired comparison with relevant untreated control and using multivariate classification of treated and untreated samples. With the main focus on early time intervals when the influence of apoptosis is minimized, we found significantly different levels of proteins, which corresponded to 1%–2% of the total amount of protein spots detected. According to Gene Ontology classification of biological processes, the highest representation of identified proteins for all three drugs belong to metabolic processes of proteins and nucleic acids and cellular processes, mainly cytoskeleton organisation and ubiquitin-proteasome pathway. Importantly, we observed significant proportion of changes in proteins involved in the generation of precursor metabolites and energy typical for daunorubicin, transport proteins participating in response to doxorubicin and a group of proteins of immune system characterising response to mitoxantrone. Both a paired comparison and the multivariate evaluation of quantitative data revealed daunorubicin as a distinct member of the group of anthracycline/anthracenedione drugs. A combination of identified drug specific protein changes, which may help to explain anti-cancer activity, together with the benefit of blocking activation of adaptive cancer pathways, presents important approaches to improving treatment outcomes in cancer.     

High‐Pressure Thermal Sterilization: Food Safety and Food Quality of Baby Food Puree

The benefits that high‐pressure thermal sterilization offers as an emerging technology could be used to produce a better overall food quality. Due to shorter dwell times and lower thermal load applied to the product in comparison to the thermal retorting, lower numbers and quantities of unwanted food processing contaminants (FPCs), for example, furan, acrylamide, HMF, and MCPD‐esters could be formed. Two spore strains were used to test the technique; Geobacillus stearothermophilus and Bacillus amyloliquefaciens, over the temperature range 90 to 121 °C at 600 MPa. The treatments were carried out in baby food puree and ACES‐buffer. The treatments at 90 and 105 °C showed that G. stearothermophilus is more pressure‐sensitive than B. amyloliquefaciens. The formation of FPCs was monitored during the sterilization process and compared to the amounts found in retorted samples of the same food. The amounts of furan could be reduced between 81% to 96% in comparison to retorting for the tested temperature pressure combination even at sterilization conditions of F₀‐value in 7 min.     

Effectiveness of iron reducing bacteria for the removal of iron from bauxite ores

Current study investigates the possibility of obtaining the removal of iron from bauxite ores, by exploiting the metabolism of iron reducing microorganisms. The experiments were carried out using the microorganism Desulfuromonas palmitatis. The effectiveness of the treatment was evaluated on six different bauxite samples, containing the alumina oxide in the form of diaspore or boehmite. The Fe₂O₃ content of the samples varied between 16.3% and 22.3% and occurred mainly in the form of goethite or hematite, with one sample containing also chamosite. For comparison reasons the same treatment was also applied on three samples of synthetic Fe(III)-oxides, namely ferrihydrite, goethite and hematite. The removal of iron from the six bauxite samples was found to vary between 7% and 29% and the highest extraction corresponded to the sample containing the Fe(II) rich compound, chamosite. The bioavailability of Fe in the three synthetic oxides was highly dependant on their crystallinity. The amorphous ferrihydrite was almost completely dissolved, up to 95%, whereas dissolution of crystalline goethite and hematite did not exceed 9% and 1.2% respectively.     

Comparison of the Flow of Permanent and Condensable Gases through an Asymmetric Porous Membrane

Porous inorganic membranes are usually composed of several layers, which are asymmetric with respect to the flow direction. For permanent gases, investigations about the influence of the flow direction on the mass flux through an asymmetric ceramic membrane were previously performed and can be found in literature. Mass flow differences between the two flow directions were calculated. Here the flow of condensable gases, i.e., of vapors, through the same membrane is analyzed and it is shown that the mass flow might be up to 40 % larger in one direction than in the other direction.     

First Trimester Prediction of Preterm Delivery in the Absence of Other Pregnancy-Related Complications Using Cardiovascular-Disease Associated MicroRNA Biomarkers

The aim of the study was to determine if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict within 10 to 13 weeks of gestation preterm delivery such as spontaneous preterm birth (PTB) or preterm prelabor rupture of membranes (PPROM) in the absence of other pregnancy-related complications (gestational hypertension, preeclampsia, fetal growth restriction, or small for gestational age). In addition, we assessed if aberrant expression profile of cardiovascular disease associated microRNAs would be able to predict preterm delivery before and after 34 weeks of gestation. The retrospective study was performed within the period November 2012 to March 2020. Whole peripheral blood samples were collected from 6440 Caucasian individuals involving 41 PTB and 65 PPROM singleton pregnancies. A control group, 80 singleton term pregnancies, was selected on the base of equal sample storage time. Gene expression of 29 selected cardiovascular disease associated microRNAs was studied using real-time RT-PCR. Downregulation of miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-126-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, miR-221-3p and miR-342-3p was observed in pregnancies with preterm delivery before 37 (≤36 + 6/7) weeks of gestation. Majority of downregulated microRNAs (miR-16-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p) was associated with preterm delivery occurring before 37 (≤36 + 6/7) weeks of gestation. The only miR-210-3p was downregulated in pregnancies with preterm delivery before 34 (≤33 + 6/7) weeks of gestation. The type of preterm delivery also had impact on microRNA gene expression profile. Downregulation of miR-24-3p, miR-92a-3p, miR-155-5p, and miR-210-3p was a common feature of PTB and PPROM pregnancies. Downregulation of miR-16-5p, miR-20b-5p, miR-26a-5p, miR-126-3p, miR-133a-3p, miR-146a-5p, miR-221-3p, and miR-342-3p appeared just in PTB pregnancies. No microRNA was uniquely dysregulated in PPROM pregnancies. The combination of 12 microRNAs (miR-16-5p, miR-20b-5p, miR-21-5p, miR-24-3p, miR-26a-5p, miR-92a-3p, miR-133a-3p, miR-145-5p, miR-146a-5p, miR-155-5p, miR-210-3p, and miR-342-3p, AUC 0.818, p < 0.001, 74.53% sensitivity, 75.00% specificity, cut off > 0.634) equally as the combination of 6 microRNAs (miR-16-5p, miR-21-5p, miR-24-3p, miR-133a-3p, miR-155-5p, and miR-210-3p, AUC 0.812, p < 0.001, 70.75% sensitivity, 78.75% specificity, cut off > 0.652) can predict preterm delivery before 37 weeks of gestation in early stages of gestation in 52.83% pregnancies at 10.0% FPR. Cardiovascular disease associated microRNAs represent promising biomarkers with very good diagnostical potential to be implemented into the current routine first trimester screening programme to predict preterm delivery.     

The Role of Vitamin D in Sleep Disorders of Children and Adolescents: A Systematic Review

This review investigates the association between vitamin D and sleep disorders. Vitamin D is an essential nutrient known to play an important role in the growth and bone health of the human body, but it also appears to play a role in sleep. The goal of our review is to examine the association between vitamin D and sleep disorders in children and adolescents. We summarize the evidence about the role and the mechanism of action of vitamin D in children and adolescents with sleep disorders such as insomnia, obstructive sleep apnea (OSA), restless legs syndrome (RLS), and other sleep disorders. Systematic electronic database searches were conducted using Pubmed and Cochrane Library. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed. The studies that met the established inclusion criteria were analyzed and compared. Results suggest a strict relationship between vitamin D deficiency in children and sleep disorders. There is evidence that vitamin D is implicated in the different neurochemical mechanisms involved in sleep regulation and mainly in the serotonergic and dopaminergic pathways. This might be responsible for the association of vitamin D deficiency and restless sleep, sleep hyperhidrosis, OSA, and RLS.