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51.
An infinite tree is called thin if it contains only countably many infinite branches. Thin trees can be seen as intermediate structures between infinite words and infinite trees. In this work we investigate properties of regular languages of thin trees. Our main tool is an algebra suitable for thin trees. Using this framework we characterize various classes of regular languages: commutative, open in the standard topology, and definable in weak MSO logic among all trees. We also show that in various meanings thin trees are not as rich as all infinite trees. In particular we observe a collapse of the parity index to the level (1, 3) and a collapse of the topological complexity to co-analytic sets. Moreover, a gap property is shown: a regular language of thin trees is either weak MSO-definable among all trees or co-analytic-complete.  相似文献   
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Modification of the surfaces of polycarbonate (PC) with the use of a solution of tin (II) chloride renders them hydrophilic. The surface draping is stable against exposure to water and to alcohols. Exposure to alkanes reduces but does not diminish the effect. The method is compatible—in using the same solvent and temperature—with the hydrophobic modification of PC Jankowski et al. ( Lab Chip 11:748–752, 2011). The combination of these methods makes it possible to generate single and multiple monodisperse emulsions with the use of flow-focusing junctions in systems made in PC—material that is suitable for fabrication of multilayer, high throughput microfluidic devices.  相似文献   
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The Atomic Broadcast algorithm described in this paper can deliver messages in two communication steps, even if multiple processes broadcast at the same time. It tags all broadcast messages with the local real time, and delivers all messages in the order of these timestamps. Both positive and negative statements are used: “m broadcast at time 51” vs. “no messages broadcast between times 31 and 51”. To prevent crashed processes from blocking the system, the -elected leader broadcasts negative statements on behalf of the processes it suspects () to have crashed. A new cheap Generic Broadcast algorithm is used to ensure consistency between conflicting statements. It requires only a majority of correct processes (n > 2f) and, in failure-free runs, delivers all non-conflicting messages in two steps. The main algorithm satisfies several new lower bounds, which are proved in this paper.  相似文献   
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The noncatalytic beta-subunit is responsible for the latency of casein kinase 2 (CK2) activity toward calmodulin. Twenty-one mutants of the beta-subunit bearing either deletions or Ala substitutions for charged residues in the 5-6, 55-70, and 171-178 sequences have been assayed for their ability to substitute for wild-type beta-subunit as a suppressor of activity toward calmodulin. The only mutations that reduced the ability of the beta-subunit to suppress calmodulin phosphorylation activity, though being compatible with normal reconstitution of CK2 holoenzyme, were those affecting Asp55, Glu57 and the whole triplet Glu59-Asp-Glu61. The activity of CK2 holoenzyme, either native or reconstituted, toward calmodulin can be elicited by a variety of polybasic effectors, including polylysine, polyarginine, salmine, and histones H4, H3, and, to a lesser extent, H2a and H2b. Histone H1 and polyamines are conversely ineffective. The latent "calmodulin kinase" activity of CK2 can also be specifically unmasked by a peptide (alpha[66-86]) reproducing a basic insert of the catalytic subunit. This effect is reversed by equimolar addition of a peptide (beta[55-71]) including the 55-64 acidic stretch of the beta-subunit. Comparable polylysine stimulation was observed with the holoenzymes reconstituted with either beta wt or the beta mutants capable of assembling with the alpha-subunit, with the notable exception of those bearing Ala substitutions for acidic residues at positions 55, 57, and 59-61. These were nearly insensitive to 42 nM polylysine, which conversely promotes a more than 10-fold increase of calmodulin phosphorylation with wild-type beta.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Sobieski  W  Grygo  D  Lipiński  S 《Sadhana》2016,41(11):1333-1347
Sādhanā - This paper presents the results of experimental research of the phenomena occurring in water ram during a single cycle of its operation. Apart from a brief introduction and...  相似文献   
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In metastatic breast cancer the goal to reach must be the best possible palliation with minimum discomfort for the patient. We reviewed our experience with radiotherapy (20 or 30 Gy), systemic therapy and brace. Among 2200 breast cancer patients, we extracted 28 potential candidates for resection. All of them developed new metastases outside the treated field within one year. Local control was achieved in 68%, and 80% of them had stable or better performance status at 3 months. From our analysis, even patients with a so called "solitary lesion" do not seem to have a better prognosis than others. We conclude that radiotherapy (with systemic therapy and a brace) is still first-choice treatment for vertebral metastases; CT-guided percutaneous biopsy can avoid worthless major operations. The role of surgery should be limited to neurological compression, severe mechanical instability and to salvage the failures of conservative treatment.  相似文献   
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