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221.
Dr. Francesca Salvi Dr. Bernhard Hoermann Dr. Javier del Pino García Dr. Miriam Fontanillo Assoc. Prof. Dr. Rita Derua Prof. Dr. Monique Beullens Prof. Dr. Mathieu Bollen Dr. Orsolya Barabas Prof. Dr. Maja Köhn 《Chembiochem : a European journal of chemical biology》2021,22(5):834-838
Phosphoprotein phosphatase-1 (PP1) is a key player in the regulation of phospho-serine (pSer) and phospho-threonine (pThr) dephosphorylation and is involved in a large fraction of cellular signaling pathways. Aberrant activity of PP1 has been linked to many diseases, including cancer and heart failure. Besides a well-established activity control by regulatory proteins, an inhibitory function for phosphorylation (p) of a Thr residue in the C-terminal intrinsically disordered tail of PP1 has been demonstrated. The associated phenotype of cell-cycle arrest was repeatedly proposed to be due to autoinhibition of PP1 through either conformational changes or substrate competition. Here, we use PP1 variants created by mutations and protein semisynthesis to differentiate between these hypotheses. Our data support the hypothesis that pThr exerts its inhibitory function by mediating protein complex formation rather than by a direct mechanism of structural changes or substrate competition. 相似文献
222.
Real-Time Systems - Multi-core architectures pose many challenges in real-time systems, which arise from contention between concurrent accesses to shared memory. Among the available memory... 相似文献
223.
Christian Heubner Sebastian Maletti Henry Auer Juliane Hüttl Karsten Voigt Oliver Lohrberg Kristian Nikolowski Mareike Partsch Alexander Michaelis 《Advanced functional materials》2021,31(51):2106608
The development of rechargeable batteries with high-energy density is critical for future decarbonization of transportation. Anode-free Li-ion batteries, using a bare current collector at the anode side without any excess of Li, provide the highest volumetric energy density ( > 1500 Wh L−1) among all possible cell configurations. Furthermore, elimination of the anode material coating reduces material consumption and greatly simplifies cell production, which in turn lowers costs. Although significant progress has been made recently by the application of modified current collectors, optimized cycling parameters and improved liquid electrolytes, insufficient efficiencies, and dendritic growth during lithium plating lead to poor cycle life of typically less than 100 cycles as well as safety issues. Alternatively, very recent studies have demonstrated anode-free solid-state batteries that combine the benefits of high energy anode-free cell configuration and solid-state systems with high safety, exceeding 1000 cycles. This review provides an overview of recent developments toward anode-free solid-state batteries and highlights the current issues and challenges in this nascent field. It is concluded that, although major challenges remain at the present, the lessons learned in the fields of liquid electrolytes and solid-state lithium metal batteries can accelerate the development of anode-free solid-state batteries of practical relevance. 相似文献
224.
The design of laboratory apparatus for the evaluation of the sorption capacity of solid sorbents is described in detail. The apparatus, which is easy to set up in any laboratory, consists of three basic elements: a standard mixtures generator, utilizing permeation through a PTFE membrane, a sorbent trap of controlled temperature and a flameionization detector. The apparatus enables investigation of the effect of various parameters (concentration, flow rate, temperature, co-adsorption, etc.) on sorption capacity, as measured by breakthrough parameters (breakthrough volume and time), as well as studies of the fundamental parameters of the remaining steps (sample storage, desorption and final determination) of the analysis. 相似文献
225.
This paper deals with radiation characteristics of unfurlable antennas. First, theoretical developments necessary for this study are exposed. Then, disconnection between mesh reflection properties effects and surface distortions effects is demonstrated. Then, importance of mesh parameters and mesh assembly, on cross-polarization radiation, is investigated. At last, effects of various surface distortions geometries, on copolarization radiation, are compared, and for design of such antennas, useful results are exhibited. 相似文献
226.
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228.
C Mathieu S Moreau P Frendo A Puppo MJ Davies 《Canadian Metallurgical Quarterly》1998,24(7-8):1242-1249
Electron paramagnetic resonance spectroscopy has been employed to examine the nature of the metal ions and radicals present in intact root nodules of soybean plants grown in the absence of nitrate. The spectra obtained from nodules of different ages using this non-invasive technique show dramatic differences, suggesting that there are both qualitative and quantitative changes in the metal ion and radical species present. A major component of the spectra obtained from young nodules is assigned to a complex (Lb-NO) of nitric oxide (NO.) with the heme protein leghemoglobin (Lb). This Lb-NO species, which has not been previously detected in intact root nodules of plants grown in the absence of nitrate, is thought to be formed by reaction of nitric oxide with iron(II) leghemoglobin. The nitric oxide may be generated from arginine via a nitric oxide synthase-like activity present in the nodules of the soybean plants, in a manner analogous to that recently described for Lupinus albus. This Lb-NO complex is present at lower concentrations in older nodules, and is almost completely absent from senescent nodules. Exposure of young and mature nodules to oxidant stress, in the form of hydrogen peroxide, results in changes in the EPR spectra, with the loss of the signals from the Lb-NO complex and appearance of absorptions similar to those from untreated senescent nodules. These results suggest that there are characteristic changes in both the metal ion complexes and radicals present in intact root nodules of different ages, and support the theory that nitric oxide and other radicals play a significant role in determining the nitrogen fixing activity of root nodules; the modulatory activity of NO. may involve regulation of gene activity. 相似文献
229.
G Dalpé N Leclerc A Vallée A Messer M Mathieu Y De Repentigny R Kothary 《Canadian Metallurgical Quarterly》1998,10(5-6):243-257
The mouse neurological mutant dystonia musculorum (dt) suffers from a hereditary sensory neuropathy. We have previously described the cloning and characterization of the dt gene, which we named dystonin (Dst). We had shown that dystonin is a neural isoform of bullous pemphigoid antigen 1 (Bpag1) with an N-terminal actin-binding domain. It has been shown previously that dystonin is a cytoskeletal linker protein, forming a bridge between F-actin and intermediate filaments. Here, we have used two different antibody preparations against dystonin and detected a high-molecular-weight protein in immunoblot analysis of spinal cord extracts. We also show that this high-molecular-weight protein was not detectable in the nervous system of all dt alleles tested. Immunohistochemical analysis revealed that dystonin was present in different compartments of neurons--cell bodies, dendrites, and axons, regions which are rich in the three elements of the cytoskeleton (F-actin, neurofilaments, and microtubules). Ultrastructural analysis of dt dorsal root axons revealed disorganization of the neurofilament network and surprisingly also of the microtubule network. In this context it is of interest that we observed altered levels of the microtubule-associated proteins MAP2 and tau in spinal cord neurons of different dt alleles. Finally, dt dorsal root ganglion neurons formed neurites in culture, but the cytoskeleton was disorganized within these neurites. Our results demonstrate that dystonin is essential for maintaining neuronal cytoskeleton integrity but is not required for establishing neuronal morphology. 相似文献
230.