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571.
The aim was to investigate the effect of ageing large beef cuts directly in high oxygen modified atmosphere (MA) and how ageing time in vacuum influence meat quality when followed by retail packaging in high oxygen MA. Large cuts (10 cm long) of beef loin (LD) were aged for up to 25 days postmortem in different ageing systems at 4 °C. Ageing solely in high oxygen modified atmosphere (MA, 80% O2 + 20% CO2) for 5 or 10 days and ageing in vacuum for 5 or 15 days followed by high oxygen MA for 5 or 10 days were compared with ageing in vacuum for 5, 15 and 25 days. Warner–Bratzler shear force, purge and cooking losses, calpain activity and desmin and carbonyl contents were measured. Shear force decreased to the same level when ageing this large beef cut solely in high oxygen MA for 5 or 10 days as when ageing in vacuum. The activity of μ-calpain disappeared, the activity of m-calpain decreased and purge loss increased between 5 and 10 days, but cooking loss and the contents of desmin and carbonyls were unaffected. The ageing time in vacuum before packaging of this large beef cut in high oxygen MA did not affect the ultimate shear force. The m-calpain activity decreased and the content of carbonyls increased compared with solely in vacuum after 15 days of total ageing, but there was no difference in the content of desmin or cooking loss between these ageing systems at the same ageing time. 相似文献
572.
573.
Trauma management (TM) covers two types of medical treatment: the initial one provided by Emergency Medical Services (EMS) and a further one provided by permanent medical facilities. There is a consensus in the professional literature that to reduce the severity and the number of road crash victims, the TM system should provide rapid and adequate initial care of injury, combined with sufficient further treatment at a hospital or trauma centre. Recognizing the important role of TM for reducing road crash injury outcome, it was decided, within the EU funded SafetyNet project, to develop road safety performance indicators (SPIs) which would characterize the level of TM systems’ performance in European countries and enable country comparisons. 相似文献
574.
Katrin Witte Robert Sabat Ellen Witte-Hndel Kamran Ghoreschi Kerstin Wolk 《International journal of molecular sciences》2022,23(16)
Hidradenitis suppurativa (HS; also designated as acne inversa) is a chronic inflammatory disease characterized by painful skin lesions that occur in the axillary, inguinal, gluteal and perianal areas of the body. These lesions contain recurring deep-seated, inflamed nodules and pus-discharging abscesses and fistulas. Affecting about 1% of the population, this common disease has gained appropriate clinical attention in the last years. Associated with numerous comorbidities including metabolic syndrome, HS is considered a systemic disease that severely impairs the quality of life and shortens life expectancy. Therapeutic options for HS are limited, comprising long-term antibiotic treatment, the surgical removal of affected skin areas, and neutralization of TNF-α, the only approved systemic treatment. Novel treatment options are needed to close the therapeutic gap. HS pathogenesis is increasingly better understood. In fact, neutrophilic granulocytes (neutrophils) seem to be decisive for the development of the purulent destructive skin inflammation in HS. Recent findings suggest a key role of the immune mediators IL-1β, IL-17A and G-CSF in the migration into and activation of neutrophils in the skin. Although phytomedical drugs display potent immunoregulatory properties and have been suggested as complementary therapy in several chronic disorders, their application in HS has not been considered so far. In this review, we describe the IL-1/IL-17/G-CSF axis and evaluate it as potential target for an integrated phytomedical treatment of HS. 相似文献
575.
Mai P. Tran Rakesh Chatterjee Yannik Dreher Julius Fichtler Kevin Jahnke Lennart Hilbert Vasily Zaburdaev Kerstin Göpfrich 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(13):2202711
The bottom-up construction of an artificial cell requires the realization of synthetic cell division. Significant progress has been made toward reliable compartment division, yet mechanisms to segregate the DNA-encoded informational content are still in their infancy. Herein, droplets of DNA Y-motifs are formed by liquid–liquid phase separation. DNA droplet segregation is obtained by cleaving the linking component between two populations of DNA Y-motifs. In addition to enzymatic cleavage, photolabile sites are introduced for spatio-temporally controlled DNA segregation in bulk as well as in cell-sized water-in-oil droplets and giant unilamellar lipid vesicles (GUVs). Notably, the segregation process is slower in confinement than in bulk. The ionic strength of the solution and the nucleobase sequences are employed to regulate the segregation dynamics. The experimental results are corroborated in a lattice-based theoretical model which mimics the interactions between the DNA Y-motif populations. Altogether, engineered DNA droplets, reconstituted in GUVs, can represent a strategy toward a DNA segregation module within bottom-up assembled synthetic cells. 相似文献
576.
Prof. Dr.-Ing. Michael Beckmann PD Dr.-Ing. habil. Frank Babick Prof. Dr. rer. nat. et Ing. habil. Kerstin Eckert Dr.-Ing. Sascha Heitkam Prof. Dr.-Ing. Markus Schubert Prof. Dr.-Ing. habil. Leon Urbas Prof. Dr.-Ing. habil. Michael Stintz 《化学,工程师,技术》2023,95(11):1691-1706
At the Technische Hochschule Dresden, the predecessor institution of the TU Dresden, a specialization “Engineer for Process Engineering” was established in 1953 with the filling of the specialist professorship for chemical engineering, and the present Institute for Process and Environmental Engineering was founded. Since then, the profile in education and research of the institute within the Faculty of Mechanical Science and Engineering of the Technische Universität Dresden (TUD) has been considerably extended. Based on this development, the current main research areas of the five chairs and research groups are presented. 相似文献
577.
Michel Grosse Kerstin Günther Paul M. Jordan Dávid Roman Oliver Werz Christine Beemelmanns 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200073
δ-Hydroxy-β-keto esters and δ,β-dihydroxy esters are characteristic structural motifs of statin-type natural products and drug candidates. Here, we describe the synthesis of functionalized δ-hydroxy-β-keto esters in good yields and excellent enantioselectivities using Chan's diene and modified Mukaiyama-aldol reaction conditions. Diastereoselective reduction of δ,β-dihydroxy esters afforded the respective syn- and anti-diols, and saponification yielded the corresponding acids. All products were evaluated for their anti-inflammatory properties, which uncovered a surprising structure-activity relationship. 相似文献
578.
Miguel Burgos-Ruiz Kerstin Elert Encarnacion Ruiz-Agudo Helmut Cölfen Carlos Rodriguez-Navarro 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(33):2300596
The relatively recent development of nanolimes (i.e., alcoholic dispersions of Ca(OH)2 nanoparticles) has paved the way for new approaches to the conservation of important art works. Despite their many benefits, nanolimes have shown limited reactivity, back-migration, poor penetration, and lack of proper bonding to silicate substrates. In this work a novel solvothermal synthesis process is presented by which extremely reactive nanostructured Ca(OH)2 particles are obtained using calcium ethoxide as the main precursor species. Moreover, it is demonstrated that this material can be easily functionalized with silica-gel derivatives under mild synthesis conditions, thereby preventing particle growth, increasing total specific surface area, enhancing reactivity, modifying colloidal behavior, and functioning as self-integrated coupling agents. Additionally, the formation of calcium silicate hydrate (CSH) nanocement is promoted by the presence of water, resulting in optimal bonding when applied to silicate substrates, as evidenced by the higher reinforcement effect produced on treated Prague sandstone specimens as compared to those consolidated with nonfunctionalized commercial nanolime. The functionalization of nanolimes is not only a promising strategy for the design of optimized consolidation treatments for the cultural heritage, but may also have important implications for the development of advanced nanomaterials for building, environmental, or biomedical applications. 相似文献
579.
Optical coatings and their influence on the reliability of flexible glass Flexible glass with thicknesses below 100 μm has excellent optical properties. However, due to its brittleness, processing steps like cleaning, vacuum coating and handling are challenging. A high fracture and fatigue strength is crucial for reliable processing, especially at the glass edge. Moreover, fatigue behavior is of great importance regarding early-life failure, but testing has been performed comparatively rarely. Therefore, a new stepwise fatigue test method was developed and the fatigue behavior of flexible glass with functional indium tin oxide and dielectric antireflection coatings was investigated. The fatigue strength of coated flexible glass increased significantly in almost all cases. With the new method, also other approaches to increase the strength of flexible glasses, e.g. by flash lamp annealing are currently investigated. 相似文献
580.
Moritz Kränzlein Thomas M. Pehl Kerstin Halama Paula F. Großmann Tim Kratky Amelie M. Mühlbach Bernhard Rieger 《大分子材料与工程》2023,308(6):2200635
Rare-earth metal-mediated group-transfer polymerization (REM-GTP) offers distinctive features over common polymerization techniques, such as living character, a broad scope of functional monomers, high activity, excellent control of the polymeric parameters as well as inherent chain-end functionalization. Through the latter, polymers with reactive end-groups become feasible, opening the pathway for further post-polymerization functionalization. In this study, a straightforward graft-to immobilization of the Michael-type polymer poly(diethyl vinylphosphonate) (PDEVP) on multi-walled carbon nanotubes (MWCNT) is reported. Hence, a customized azide initiator is synthesized and studied in the C H bond activation with various lanthanide-based catalysts and the subsequent polymerization of diethyl vinylphosphonate (DEVP). The successful attachment of the azide end-group is demonstrated via electrospray ionization mass spectrometry (ESI-MS) and the synthesized polymers are subjected to immobilization on multi-walled carbon nanotubes in a graft-to approach. The prepared MWCNT:PDEVP composites are analyzed via thermogravimetric analysis (TGA), elemental analysis (EA), Raman spectroscopy, X-Ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) and the versatility of this approach is shown via the stabilization of MWCNT dispersions in water. 相似文献