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Philipp vom Berge 《The Annals of Regional Science》2013,50(3):731-751
This paper develops a general equilibrium geographical economics model, which uses matching frictions on the labor market to generate regional unemployment disparities alongside the usual core-periphery pattern of industrial agglomeration. In the model, regional wage differentials do not only influence migration decisions of mobile workers, but also affect the bargaining process on local labor markets, leading to differences in vacancies and unemployment as well. In a setting with two regions, both higher or lower unemployment rates in the core region are possible equilibrium outcomes, depending on transport costs and the elasticity of substitution. Stylized facts suggest that both patterns are of empirical relevance. 相似文献
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Judit Molnár Gábor J. Szebeni Boglárka Csupor-L?ffler Zsuzsanna Hajdú Thomas Szekeres Philipp Saiko Imre Ocsovszki László G. Puskás Judit Hohmann István Zupkó 《International journal of molecular sciences》2016,17(2)
Plants and plant extracts play a crucial role in the research into novel antineoplastic agents. Four sesquiterpene lactones, artecanin (1), 3β-chloro-4α,10α-dihydroxy-1α,2α-epoxy-5α,7αH-guaia-11(13)-en-12,6α-olide (2), iso-seco-tanapartholide 3-O-methyl ether (3) and 4β,15-dihydro-3-dehydrozaluzanin C (4), were isolated from two traditionally used Asteraceae species (Onopordum acanthium and Artemisia asiatica). When tested for antiproliferative action on HL-60 leukemia cells, these compounds exhibited reasonable IC50 values in the range 3.6–13.5 μM. Treatment with the tested compounds resulted in a cell cycle disturbance characterized by increases in the G1 and G2/M populations, while there was a decrease in the S phase. Additionally, 1–3 elicited increases in the hypodiploid (subG1) population. The compounds elicited concentration-dependent chromatin condensation and disruption of the membrane integrity, as revealed by Hoechst 33258–propidium staining. Treatment for 24 h resulted in significant increases in activity of caspases-3 and -9, indicating that the tested sesquiterpenes induced the mitochondrial pathway of apoptosis. The proapoptotic properties of the sesquiterpene lactones were additionally demonstrated withannexin V staining. Compounds 1 and 2 increased the Bax/Bcl-2 expression and decreased the expressions of CDK1 and cyclin B2, as determined at the mRNA level by means of RT-PCR. These experimental results indicate that sesquiterpene lactones may be regarded as potential starting structures for the development of novel anticancer agents. 相似文献
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Jielin Li Rennie B. Kaunda Shrey Arora Philipp Hartlieb Priscilla P. Nelson 《岩石力学与岩土工程学报(英文版)》2019,11(2)
Fully-coupled thermo-mechanical simulations are implemented in COMSOL Multiphysics to investigate micro-scale stress-strain variability in pegmatite specimens subjected to thermal loading using microwaves. Thermally-induced compressive and tensile stresses increase as the microwave irradiation duration increases. The dielectric constant, coefficient of expansion, and type and size of mineralogical boundary have significant impacts on the responses of the rock to microwave irradiation. The maximum principal stress of the chlorite is the smallest, indicating that the chlorite experiences the most damage under microwave irradiation, followed by the quartz. The maximum principal stress values of plagioclase and orthoclase are larger, indicating that they are likely to incur the least damage. Where quartz or chlorite is dominant, the resulting von Mises stresses are consistently higher after 120 s of microwave irradiation. The rate of generation of von Mises stresses increases most rapidly along the interface between quartz and plagioclase, and the interface between quartz and orthoclase, followed by the interface between quartz and chlorite, and finally the interface between plagioclase and orthoclase. The presented modeling approach provides a practical method to investigate stress-strain relationships within mineralogical boundaries inside a rock thin section. 相似文献
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Philipp Wolf Alexander Mohr Georgina Gavins Victoria Behr Karin Mörl Prof. Oliver Seitz Prof. Annette G. Beck-Sickinger 《Chembiochem : a European journal of chemical biology》2022,23(6):e202100340
Fine-tuning of G protein-coupled receptor (GPCR) signaling is important to maintain cellular homeostasis. Recent studies demonstrated that lateral GPCR interactions in the cell membrane can impact signaling profiles. Here, we report on a one-step labeling method of multiple membrane-embedded GPCRs. Based on short peptide tags, complementary probes transfer the cargo (e. g. a fluorescent dye) by an acyl transfer reaction with high spatial and temporal resolution within 5 min. We applied this approach to four receptors of the cardiovascular system: the endothelin receptor A and B (ETAR and ETBR), angiotensin II receptor type 1, and apelin. Wild type-like G protein activation after N-terminal modification was demonstrated for all receptor species. Using FRET-competent dyes, a constitutive proximity between hetero-receptors was limited to ETAR/ETBR. Further, we demonstrate, that ETAR expression regulates the signaling of co-expressed ETBR. Our orthogonal peptide-templated labeling of different GPCRs provides novel insight into the regulation of GPCR signaling. 相似文献
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About 80% of the chemical products are still based on crude oil. Bio-based materials will increasingly gain importance. As the fraction of oxygen is normally higher in biomass than in crude oil as well as in the derived conventional products, this implies a need to develop new synthesis pathways. Depending on the types of new synthesis pathways, the effects of a complete raw-material change on land and exergy use differ. Here, different synthesis pathways starting from glucose and plant oil to different kinds of end products are evaluated utilizing material and exergy balances. These evaluations are carried out under today's and future conditions and constraints, like yield, demand of organic chemicals and world population. The analysis in this paper shows that the land and energy use can be significantly reduced, if the products are adapted to the chemical structure of their bio-based feedstock. 相似文献
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Ive Hermans Joaquim Henrique Teles Richard Dehn Till-Christian Brüggemann Robert Send Philipp Nikolaus Plessow 《Topics in Catalysis》2014,57(14-16):1256-1264
In this contribution we use computational tools to investigate the reaction of alcohol substrates with reactive nitrogen oxide species such as N2O3 and N2O4, leading to the formation of alkyl nitrites. These nitrites are interesting intermediates which can be processed to various valuable chemicals such as ketones/aldehydes and dimethyl oxalate while regenerating NO x . As such, NO x is used as an oxidation mediator, converting alcohol substrates to more reactive nitrites which can be selectively converted to more desired compounds, closing a catalytic cycle in NO x species. 相似文献