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991.
Doklady Mathematics - In this paper we extend Y. Eliashberg’s theorem on the maps with fold type singularities to arbitrary Thom-Boardman singularities. Namely, we state a necessary and... 相似文献
992.
Doklady Mathematics - This paper shows the integrability of certain classes of odd-order dynamical systems that are homogeneous with respect to some of the variables and in which a system on the... 相似文献
993.
N. Stallkamp S. Ringleb B. Arndt M. Kiffer S. Kumar T. Morgenroth G.G. Paulus W. Quint Th. Stöhlker M. Vogel 《X射线光谱测定》2020,49(1):188-191
Detailed investigations of laser–ion interactions require well-defined ion targets and detection techniques for high-sensitivity measurements of reaction educts and products. To this end, we have designed and built the High-Intensity Laser-Ion Trap Experiment Penning trap setup, which features various ion-target preparation techniques including selection, cooling, compression, and positioning as well as destructive and non-destructive measurement techniques to determine the number of stored ions for all charge states individually and simultaneously. We have recently performed first commissioning experiments of ion deceleration and dynamic ion capture with highly charged ion bunches from an electron beam ion source. We have characterized our single-pass non-destructive ion counter in detail and were able to determine the ion velocity as well as the number of ions from the signals acquired. 相似文献
994.
Morgunov R. B. Bezverkhnii A. I. Dmitriev O. S. Bakhmet’ev M. V. 《Physics of the Solid State》2020,62(3):458-463
Physics of the Solid State - It has been established that nonmonotonic magnetization relaxation in Pt/Co/Ir/Co/Pt synthetic ferrimagnets (SF) with perpendicular magnetic anisotropy is caused by the... 相似文献
995.
Kamzin A. S. Valiullin A. A. Bingolbali A. Doǧan N. 《Physics of the Solid State》2020,62(7):1231-1239
Physics of the Solid State - Changes in the structure and properties of the Ni1 – xCuxFe2O4 ferrites-spinel magnetic nanoparticles depending on the Cu ion concentration (0... 相似文献
996.
Hctor Solís-Chagoyn Aline Domínguez-Alonso Marcela Valds-Tovar Jesús Argueta Zuly A. Snchez-Florentino Eduardo Calixto Gloria Benítez-King 《Molecules (Basel, Switzerland)》2020,25(23)
The pro-oxidant compound okadaic acid (OKA) mimics alterations found in Alzheimer’s disease (AD) as oxidative stress and tau hyperphosphorylation, leading to neurodegeneration and cognitive decline. Although loss of dendrite complexity occurs in AD, the study of this post-synaptic domain in chemical-induced models remains unexplored. Moreover, there is a growing expectation for therapeutic adjuvants to counteract these brain dysfunctions. Melatonin, a free-radical scavenger, inhibits tau hyperphosphorylation, modulates phosphatases, and strengthens dendritic arbors. Thus, we determined if OKA alters the dendritic arbors of hilar hippocampal neurons and whether melatonin prevents, counteracts, or reverses these damages. Rat organotypic cultures were incubated with vehicle, OKA, melatonin, and combined treatments with melatonin either before, simultaneously, or after OKA. DNA breaks were assessed by TUNEL assay and nuclei were counterstained with DAPI. Additionally, MAP2 was immunostained to assess the dendritic arbor properties by the Sholl method. In hippocampal hilus, OKA increased DNA fragmentation and reduced the number of MAP2(+) cells, whereas melatonin protected against oxidation and apoptosis. Additionally, OKA decreased the dendritic arbor complexity and melatonin not only counteracted, but also prevented and reversed the dendritic arbor retraction, highlighting its role in post-synaptic domain integrity preservation against neurodegenerative events in hippocampal neurons. 相似文献
997.
Marianna V. Rodrigues Fbio S. Zanuzzo Joo Fernando A. Koch Carlos Alberto F. de Oliveira Petr Sima Vaclav Vetvicka 《Molecules (Basel, Switzerland)》2020,25(22)
Administration of β-glucans through various routes, including immersion, dietary inclusion, or injection, have been found to stimulate various facets of immune responses, such as resistance to infections and resistance to environmental stress. β-Glucans used as an immunomodulatory food supplement have been found beneficial in eliciting immunity in commercial aquaculture. Despite extensive research involving more than 3000 published studies, knowledge of the receptors involved in recognition of β-glucans, their downstream signaling, and overall mechanisms of action is still lacking. The aim of this review is to summarize and discuss what is currently known about of the use of β-glucans in fish. 相似文献
998.
The incorporation of comonomers during ethylene polymerization can efficiently modulate important material properties of the polyolefins. Utilizing bioresourced comonomers for the generation of high‐performance polyolefin materials is attractive from a sustainability point of view. In this contribution, bioresourced eugenol and related comonomers were incorporated into polyolefins through palladium‐catalyzed copolymerization and terpolymerization reactions. Importantly, high‐molecular‐weight catechol‐functionalized polyolefins can be generated. The introduction of different metal ions induces efficient interactions with the incorporated catechol groups, leading to enhanced mechanical properties and self‐healing properties. Moreover, the catechol functionality can greatly improve other properties such as surface properties, adhesion properties, and compatibilizing properties. The catechol‐functionalized polyolefin was demonstrated as a versatile platform polymer for accessing various materials with dramatically different properties. 相似文献
999.
Numerical Algorithms - In this paper, the future unknown-transpose matrix inequality (FUTMI) as well as scalar inequality is formulated and investigated for the first time. This particular class of... 相似文献
1000.
The Swendsen‐Wang (SW) dynamics is a popular Markov chain for sampling from the Gibbs distribution for the ferromagnetic Ising model on a graph G = (V,E). The dynamics is conjectured to converge to equilibrium in O(|V|1/4) steps at any (inverse) temperature β, yet there are few results providing o(|V|) upper bounds. We prove fast convergence of the SW dynamics on general graphs in the tree uniqueness region. In particular, when β < βc(d) where βc(d) denotes the uniqueness/nonuniqueness threshold on infinite d‐regular trees, we prove that the relaxation time (i.e., the inverse spectral gap) of the SW dynamics is Θ(1) on any graph of maximum degree d ≥ 3. Our proof utilizes a monotone version of the SW dynamics which only updates isolated vertices. We establish that this variant of the SW dynamics has mixing time and relaxation time Θ(1) on any graph of maximum degree d for all β < βc(d). Our proof technology can be applied to general monotone Markov chains, including for example the heat‐bath block dynamics, for which we obtain new tight mixing time bounds. 相似文献