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In order to characterize the yield behavior of polypropylene as a function of pressure and to verify the applicability of the Drucker-Prager yield function, various tests were conducted to cover a wide range of stress states from uniaxial tension and compression to multiaxial tension and confined compression. Tests were performed below and above the glass transition temperature, to study the combined effect of pressure and temperature. The pressure sensitivity coefficient as an intrinsic material parameter was determined as a function of temperature. Increasing pressure sensitivity values were found with increasing temperature, which can be related to the change in the free volume and thus, to the enhanced molecular mobility. A best-fit Drucker-Prager yield function was applied to the experimental yield stresses and an average error between the predictions and the measurements of 7 % was obtained.

Polypropylene (PP) hybrid composites were prepared by the combination of three reinforcing (carbon, glass, and wood) and a synthetic (PVA) fiber. Tensile and impact testing, acoustic emission measurements, and scanning electron microscopy (SEM) were used for the characterization of the composites as well as to follow deformation and failure processes. The results obtained prove that the novel concept of using synthetic fibers for impact modification can be applied successfully also with PVA fibers. The extent of improvement in impact strength depends on fiber type and content, but also on interfacial adhesion which strongly influences the local deformation processes occurring around the fibers during fracture. Both the reinforcing and the synthetic fibers take part in these processes and contribute to energy consumption. Debonding and the subsequent plastic deformation of the matrix consumes energy the most efficiently, but the fracture of the PVA fibers also requires energy; thus, PVA fibers improve impact resistance both at poor and good adhesion. This approach allows the design of materials for structural applications; the combination of a stiffness of 4–6 GPa and an impact resistance of 20–25 kJ/m2 exceeds the properties of most PP composites available on the market. [ABSTRACT FROM AUTHOR]

In many industrial applications where compressed air is used it is necessary to increase the quality of the air by decreasing its humidity. This is done by either a condensation or adsorption dryer in the compressor circuit. In this article, the focus is on an industrial adsorption air dryer. The dryer is briefly described together with its function and a selected range of adsorbents suitable for air drying. The paper further deals with the development of a mathematical model of air humidity adsorption which is based on the Pseudo Gas-side Controlled (PGC) model. This paper contains a detailed description of the model and describes its implementation in MATLAB. Finally, the results of the simulations are discussed.

The article describes a numerical simulation of flow in the cooling system of an electromagnetic calorimeter by analysing the temperature and pressure fields. Two fundamentally different approaches were used to analyse the pressure field - analytical 1D calculation and numerical 3D flow simulation. The article contains a detailed evaluation and description of individual analyses using the commercial software ANSYS 2020 R1.

A passive wireless high-temperature sensor for far-field applications was developed for stable temperature sensing up to 1000 °C. The goal is to leverage the properties of electroceramic materials, including adequate electrical conductivity, high-temperature resilience, and chemical stability in harsh environments. Initial sensors were fabricated using Ag for operation to 600 °C to achieve a baseline understanding of temperature sensing principles using patch antenna designs. Fabrication then followed with higher temperature sensors made from (In, Sn) O 2 (ITO) for evaluation up to 1000 °C. A patch antenna was modeled in ANSYS HFSS to operate in a high-frequency region (2.5-3.5 GHz) within a 50 × 50 mm 2 confined geometric area using characteristic material properties. The sensor was fabricated on Al 2 O 3 using screen printing methods and then sintered at 700 °C for Ag and 1200 °C for ITO in an ambient atmosphere. Sensors were evaluated at 600 °C for Ag and 1000 °C for ITO and analyzed at set interrogating distances up to 0.75 m using ultra-wideband slot antennas to collect scattering parameters. The sensitivity (average change in resonant frequency with respect to temperature) from 50 to 1000 °C was between 22 and 62 kHz/°C which decreased as interrogating distances reached 0.75 m.

Based on pharmacokinetic studies carried out according to the methodologies defined by the European Medicines Agency (EMA) using mass spectrometry analysis, a new formulation of a veterinary drug for the treatment of broiler chickens is proposed. Currently, the traditional trimethoprim-sulfamethoxazole drug used for broilers is applied in a 1:5 ratio, and the recommended dose is 45 mg kg -1 of live weight administered at 24 h intervals for 3 to 5 days. In this study, we propose a novel combination containing similar active substances in a newly established ratio of 1:4, with a recommended dosage of 20 mg kg -1 of live weight administered at 24 h intervals for 3 to 5 days. With this method, the currently recommended dose of the traditional trimethoprim-sulfamethoxazole drug used for broilers can be reduced by more than half. The efficacy of the newly designed formulation and dosage of the drug was verified in a bioassay for the treatment of broilers experimentally infected with an avian pathogenic strain of Escherichia coli . In the experiment, we compared the newly designed dosage with the traditional dosage in terms of efficacy and dosage. There were no statistically significant differences between the two drugs in efficacy regarding the survival of chickens after experimental infection or changes in their health status. The experimental results suggest that a significant reduction in the recommended daily dose of drugs containing trimethoprim and sulfamethoxazole for the treatment of bacterial infections in broilers is possible and can support the prudent use of antimicrobials, including the limitation of their overuse.

The standard management for residual osteomyelitis following amputation in a diabetic foot infection includes a prolonged course of intravenous antibiotic agents. The purpose of this analysis was to investigate whether oral antibiotic therapy led to treatment failure more than intravenous antibiotic therapy for this indication. The primary endpoint was treatment failure within one year of the initial amputation, defined by re-operation for residual osteomyelitic infection or a remaining nonhealing wound at the surgical site. All patients received at least 4 weeks of antibiotics and were chosen for oral or intravenous route of administration by infectious disease specialists. Characteristics including age, sex, hemoglobin A1c, BMI, tobacco use, PVD, homelessness and IDSA classification were also assessed for influence on antibiotic success and failure. Of the 65 patients meeting inclusion criteria, treatment failure occurred in 32 and treatment success occurred in 33. Of the treatment failures, 17 (53%) were in the intravenous group, and 15 (47%) were in the oral group. The differences between the modalities of antibiotic administration and their failure rates were not found to be statistically significant (p = .28 (proportional difference: -14%, 95% confidence interval [CI]:-36% to 10%))., (Copyright © 2021 the American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.)

Postweaning diarrhea is a common issue in pig production which is currently controlled by feed supplementation with zinc oxide. However, new alternatives are being sought due to an expected ban on zinc oxide in feed supplementation from 2022 in the EU. One possible alternative is to use novel types of probiotics consisting of microbiota characteristic for healthy weaned piglets. In this study, we therefore collected rectal swabs of piglets 3 days before weaning and 4 days after weaning in a commercial farm considering all risks of field trial like the use of antibiotics, classified the piglets as predisposed, healthy or sick and using 16S rRNA sequencing, we determined and compared the microbiota composition. Increased Actinobacteria before weaning was a marker of piglets predisposed for diarrhea. Increased Chlamydia or Helicobacter before weaning was surprisingly a marker of healthy and resistant piglets after weaning. After weaning, unclassified Clostridiales, Deltaproteobacteria, Selenomonadales, Fusobacterium, Akkermansia or Anaerovibrio increased in microbiota of piglets with postweaning diarrhea while an increase in Prevotella and Faecalibacterium was characteristic for healthy, weaned piglets. Both changes in individual microbiota members and also correct timing of microbiota reshaping around weaning and the increase of mainly Prevotella species just after weaning are equally important for resistance to postweaning diarrhea in piglets under field conditions., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Short fibre reinforced polymers are getting more important for structural applications. Becasue of lightweight actions, components are designed for a specific application and lifetime. The bearable numbers of cycles can be estimated using material data and models for the consideration of influence factors. Further static loadings affect material behaviour, which influences the component lifetime. Commonly used models are not able to capture these effects. Therefore, material tests, with different load sequences, on 40% short glass fibre reinforced polypropylene have been performed. These sequences are combinations of cyclic and static loads at different, defined levels. Our research shows a lifetime elongation or reduction of a polymer, depending on the amount of static load time and quantity. For a certain stress level, the time to failure can be elongated or shortened more than a decade by another stress level, as compared to pure cyclic load. Additionally, the stiffness development of the composite is investigated in order to capture the damage course. Accordingly, these effects needed to be considered in lifetime prediction.

Aging research aims at developing therapies that delay normal aging processes and some related pathologies. Recently, many compounds and extracts from natural products have been shown to slow aging and/or extend lifespan. Marine sponges and their associated microorganisms have been found to produce a wide variety of bioactive secondary metabolites; however, those from the Southwest of the Indian Ocean are much less studied, especially regarding anti-aging activities. In this study, the microbial diversity of the marine sponge Scopalina hapalia was investigated by metagenomic analysis. Twenty-six bacterial and two archaeal phyla were recovered from the sponge, of which the Proteobacteria phylum was the most abundant. In addition, 30 isolates from S. hapalia were selected and cultivated for identification and secondary metabolites production. The selected isolates were affiliated to the genera Bacillus , Micromonospora , Rhodoccocus , Salinispora , Aspergillus , Chaetomium , Nigrospora and unidentified genera related to the family Thermoactinomycetaceae . Crude extracts from selected microbial cultures were found to be active against seven clinically relevant targets (elastase, tyrosinase, catalase, sirtuin 1, Cyclin-dependent kinase 7 (CDK7), Fyn kinase and proteasome). These results highlight the potential of microorganisms associated with a marine sponge from Mayotte to produce anti-aging compounds. Future work will focus on the isolation and the characterization of bioactive compounds.

Chemical study of the CH2Cl2-MeOH (1:1) extract from the sponge Haliclona sp. collected in Mayotte highlighted three new long-chain highly oxygenated polyacetylenes, osirisynes G-I ( 1 - 3 ) together with the known osirisynes A ( 4 ), B ( 5 ), and E ( 6 ). Their structures were elucidated by 1D and 2D NMR spectra and HRESIMS and MS/MS data. All compounds were evaluated on catalase and sirtuin 1 activation and on CDK7, proteasome, Fyn kinase, tyrosinase, and elastase inhibition. Five compounds ( 1 ; 3 - 6 ) inhibited proteasome kinase and two compounds ( 5 - 6 ) inhibited CDK7 and Fyn kinase. Osirisyne B ( 5 ) was the most active compound with IC 50 on FYNB kinase, CDK7 kinase, and proteasome inhibition of 18.44 µM, 9.13 µM, and 0.26 µM, respectively.