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60Arbuscular mycorrhizal fungi are considered as a potential biotechnological tool for improving phytostabilization efficiency and plant tolerance to heavy metal-contaminated soils. However, the mechanisms through which AMF help to alleviate metal toxicity in plants are still poorly understood. A greenhouse experiment was conducted to evaluate the effects of two AMF species on the growth, Pb accumulation, photosynthesis and antioxidant enzyme activities of a leguminous tree at Pb addition levels o…Read more
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132Bounding non- GL ₂ and R.E.AJournal of Symbolic Logic 74 (3): 989-1000. 2009.We prove that every Turing degree a bounding some non-GL₂ degree is recursively enumerable in and above (r.e.a.) some 1-generic degree.
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36Luzin’s (n) and randomness reflectionJournal of Symbolic Logic 87 (2): 802-828. 2022.We show that a computable function $f:\mathbb R\rightarrow \mathbb R$ has Luzin’s property if and only if it reflects $\Pi ^1_1$ -randomness, if and only if it reflects $\Delta ^1_1$ -randomness, and if and only if it reflects ${\mathcal {O}}$ -Kurtz randomness, but reflecting Martin–Löf randomness or weak-2-randomness does not suffice. Here a function f is said to reflect a randomness notion R if whenever $f$ is R-random, then x is R-random as well. If additionally f is known to have bounded va…Read more
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67Arithmetical Sacks ForcingArchive for Mathematical Logic 45 (6): 715-720. 2006.We answer a question of Jockusch by constructing a hyperimmune-free minimal degree below a 1-generic one. To do this we introduce a new forcing notion called arithmetical Sacks forcing. Some other applications are presented.
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29Zheng ju xiang guan xing yan jiu =Beijing da xue chu ban she. 2008.本书从界定证据相关性的内涵入手,分别探讨了逻辑上的相关性和法律上的相关性,从而澄清了一些在借鉴英美国家证据规则时出现的概念混淆。
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60Gray Matter Volume and Functional Connectivity in Hypochondriasis: A Magnetic Resonance Imaging and Support Vector Machine AnalysisFrontiers in Human Neuroscience 14. 2020.Objective: Patients with hypochondriasis hold unexplainable beliefs and a fear of having a lethal disease, with poor compliances and treatment response to psychotropic drugs. Although several studies have demonstrated that patients with hypochondriasis demonstrate abnormalities in brain structure and function, gray matter volume and functional connectivity in hypochondriasis still remain unclear.Methods: The present study collected T1-weighted and resting-state functional magnetic resonance imag…Read more
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49An application of recursion theory to analysisBulletin of Symbolic Logic 26 (1): 15-25. 2020.Mauldin [15] proved that there is an analytic set, which cannot be represented by $B\cup X$ for some Borel set B and a subset X of a $\boldsymbol{\Sigma }^0_2$ -null set, answering a question by Johnson [10]. We reprove Mauldin’s answer by a recursion-theoretical method. We also give a characterization of the Borel generated $\sigma $ -ideals having approximation property under the assumption that every real is constructible, answering Mauldin’s question raised in [15].
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23Responsible Management Education in the Digital Age: An Experiment with Liberal Art and Science Education in ChinaIn Christian Hauser & Wolfgang Amann (eds.), The Future of Responsible Management Education: University Leadership and the Digital Transformation Challenge, Springer Verlag. pp. 79-98. 2023.Machine learning algorithms now sweep the world to train machines to learn and make decisions similar to a human. These algorithms provide recommendations and sometimes make judgments on a human’s behalf. However, machine learning creates a disconnect between the intention of human beings and the results of machine learning algorithms, which is defined as the alignment problem. This chapter aims to establish what is required for future leaders to address the alignment problem and the related eth…Read more
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55Luzin’s (n) and randomness reflectionJournal of Symbolic Logic 1-27. 2020.We show that a computable function $f:\mathbb R\rightarrow \mathbb R$ has Luzin’s property if and only if it reflects $\Pi ^1_1$ -randomness, if and only if it reflects $\Delta ^1_1$ -randomness, and if and only if it reflects ${\mathcal {O}}$ -Kurtz randomness, but reflecting Martin–Löf randomness or weak-2-randomness does not suffice. Here a function f is said to reflect a randomness notion R if whenever $f$ is R-random, then x is R-random as well. If additionally f is known to have bounded va…Read more
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43Chaitin’s ω as a continuous functionJournal of Symbolic Logic 85 (1): 486-510. 2020.We prove that the continuous function${\rm{\hat \Omega }}:2^\omega \to $ that is defined via$X \mapsto \mathop \sum \limits_n 2^{ - K\left} $ for all $X \in {2^\omega }$ is differentiable exactly at the Martin-Löf random reals with the derivative having value 0; that it is nowhere monotonic; and that $\mathop \smallint \nolimits _0^1{\rm{\hat{\Omega }}}\left\,{\rm{d}}X$ is a left-c.e. $wtt$-complete real having effective Hausdorff dimension ${1 / 2}$.We further investigate the algorithmic proper…Read more
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266Higher kurtz randomnessAnnals of Pure and Applied Logic 161 (10): 1280-1290. 2010.A real x is -Kurtz random if it is in no closed null set . We show that there is a cone of -Kurtz random hyperdegrees. We characterize lowness for -Kurtz randomness as being -dominated and -semi-traceable
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112Maximal pairs of c.e. reals in the computably Lipschitz degreesAnnals of Pure and Applied Logic 162 (5): 357-366. 2011.Computably Lipschitz reducibility , was suggested as a measure of relative randomness. We say α≤clβ if α is Turing reducible to β with oracle use on x bounded by x+c. In this paper, we prove that for any non-computable real, there exists a c.e. real so that no c.e. real can cl-compute both of them. So every non-computable c.e. real is the half of a cl-maximal pair of c.e. reals
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94Maximal Chains in the Turing DegreesJournal of Symbolic Logic 72 (4): 1219-1227. 2007.We study the problem of existence of maximal chains in the Turing degrees. We show that: 1. ZF+DC+"There exists no maximal chain in the Turing degrees" is equiconsistent with ZFC+"There exists an inaccessible cardinal"; 2. For all a ∈ 2ω.(ω₁)L[a] = ω₁ if and only if there exists a $\Pi _{1}^{1}[a]$ maximal chain in the Turing degrees. As a corollary, ZFC + "There exists an inaccessible cardinal" is equiconsistent with ZFC + "There is no (bold face) $\utilde{\Pi}{}_{1}^{1}$ maximal chain of Turin…Read more
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235Lowness and Π₂⁰ nullsetsJournal of Symbolic Logic 71 (3): 1044-1052. 2006.We prove that there exists a noncomputable c.e. real which is low for weak 2-randomness, a definition of randomness due to Kurtz, and that all reals which are low for weak 2-randomness are low for Martin-Löf randomness
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74Measure Theory Aspects of Locally Countable OrderingsJournal of Symbolic Logic 71 (3). 2006.We prove that for any locally countable $\Sigma _{1}^{1}$ partial order P = 〈2ω,≤P〉, there exists a nonmeasurable antichain in P. Some applications of the result are also presented
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19On the hausdorff dimension of maximal chains and antichains of turing and hyperarithmetic degreesArchive for Mathematical Logic 65 (2): 213-238. 2025.This paper investigates the Hausdorff dimension properties of chains and antichains in Turing degrees and hyperarithmetic degrees. Our main contributions are threefold: First, for antichains in hyperarithmetic degrees, we prove that every maximal antichain necessarily attains Hausdorff dimension 1. Second, regarding chains in Turing degrees, we establish the existence of a maximal chain with Hausdorff dimension 0. Furthermore, under the assumption that $$\omega _1=(\omega _1)^L$$, we demonstrate…Read more
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23Verantwortungsvolle Managementausbildung im digitalen Zeitalter: Ein Experiment mit liberaler Kunst- und Wissenschaftsausbildung in ChinaIn Christian Hauser & Wolfgang Amann (eds.), Die Zukunft der verantwortungsvollen Managementausbildung: Universitätsführung und die Herausforderung der digitalen Transformation, Springer Nature Switzerland. pp. 89-111. 2025.Maschinelles Lernen Algorithmen durchziehen nun die Welt, um Maschinen zu trainieren und Entscheidungen ähnlich wie ein Mensch zu treffen. Diese Algorithmen liefern Empfehlungen und treffen manchmal Urteile im Namen eines Menschen. Maschinelles Lernen schafft jedoch eine Diskrepanz zwischen der Absicht des Menschen und den Ergebnissen der Algorithmen für maschinelles Lernen, die als das Ausrichtungsproblem definiert wird. Dieses Kapitel zielt darauf ab, festzustellen, was zukünftige Führungskräf…Read more
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42Some more results on relativized Chaitin's ΩAnnals of Pure and Applied Logic 176 (8): 103586. 2025.
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119Conference on Computability, Complexity and RandomnessBulletin of Symbolic Logic 14 (4): 548-549. 2008.
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30Proceedings of the 14th and 15th Asian Logic Conferences (edited book)World Scientific Publishing Company. 2019.The Asian Logic Conference (ALC) is a major international event in mathematical logic. It features the latest scientific developments in the fields of mathematical logic and its applications, logic in computer science, and philosophical logic. The ALC series also aims to promote mathematical logic in the Asia-Pacific region and to bring logicians together both from within Asia and elsewhere for an exchange of information and ideas. This combined proceedings volume represents works presented or a…Read more
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91Eye-movement evidence of the time-course of attentional bias for threatening pictures in test-anxious studentsCognition and Emotion 31 (4): 781-790. 2017.
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39A Reducibility Related To Being Hyperimmune-freeAnnals of Pure and Applied Logic 165 (7-8): 1291-1300. 2014.The main topic of the present work is the relation that a set X is strongly hyperimmune-free relative to Y . Here X is strongly hyperimmune-free relative to Y if and only if for every partial X -recursive function p there is a partial Y -recursive function q such that every a in the domain of p is also in the domain of q and satisfies p
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104The Kolmogorov complexity of random realsAnnals of Pure and Applied Logic 129 (1-3): 163-180. 2004.We investigate the initial segment complexity of random reals. Let K denote prefix-free Kolmogorov complexity. A natural measure of the relative randomness of two reals α and β is to compare complexity K and K. It is well-known that a real α is 1-random iff there is a constant c such that for all n, Kn−c. We ask the question, what else can be said about the initial segment complexity of random reals. Thus, we study the fine behaviour of K for random α. Following work of Downey, Hirschfeldt and L…Read more
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109Lowness for genericityArchive for Mathematical Logic 45 (2): 233-238. 2006.We study lowness for genericity. We show that there exists no Turing degree which is low for 1-genericity and all of computably traceable degrees are low for weak 1-genericity
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88Characterizing strong randomness via Martin-Löf randomnessAnnals of Pure and Applied Logic 163 (3): 214-224. 2012.
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113A new proof of Friedman's conjectureBulletin of Symbolic Logic 17 (3): 455-461. 2011.We give a new proof of Friedman's conjecture that every uncountable Δ11 set of reals has a member of each hyperdegree greater than or equal to the hyperjump
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120On Σ₁-Structural Differences among Finite Levels of the Ershov HierarchyJournal of Symbolic Logic 71 (4). 2006.We show that the structure R of recursively enumerable degrees is not a Σ₁-elementary substructure of Dn, where Dn (n &gt 1) is the structure of n-r.e. degrees in the Ershov hierarchy
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151On the Definable Ideal Generated by Nonbounding C.E. DegreesJournal of Symbolic Logic 70 (1). 2005.Let [NB]₁ denote the ideal generated by nonbounding c.e. degrees and NCup the ideal of noncuppable c.e. degrees. We show that both [NB]₁ ∪ NCup and the ideal generated by nonbounding and noncuppable degrees are new, in the sense that they are different from M, [NB]₁ and NCup—the only three known definable ideals so far