•  60
    Arbuscular 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
  •  132
    Bounding non- GL ₂ and R.E.A
    with Klaus Ambos-Spies, Decheng Ding, and Wei Wang
    Journal 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.
  •  36
    Luzin’s (n) and randomness reflection
    with Arno Pauly and Linda Westrick
    Journal 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
  •  67
    Arithmetical Sacks Forcing
    with Rod Downey
    Archive 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.
  •  29
    Zheng 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。
  •  60
    Gray Matter Volume and Functional Connectivity in Hypochondriasis: A Magnetic Resonance Imaging and Support Vector Machine Analysis
    with Zhe Shen, Zhiyong Zhao, Kangyu Jin, Fen Pan, Shaohua Hu, Shangda Li, Yi Xu, Dongrong Xu, and Manli Huang
    Frontiers 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
  •  49
    An application of recursion theory to analysis
    Bulletin 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].
  •  23
    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
  •  55
    Luzin’s (n) and randomness reflection
    with Arno Pauly and Linda Westrick
    Journal 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
  •  43
    Chaitin’s ω as a continuous function
    with Rupert Hölzl, Wolfgang Merkle, Joseph Miller, and Frank Stephan
    Journal 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
  •  73
    Basis theorems for -sets
    with Chi Tat Chong and Liuzhen Wu
    Journal of Symbolic Logic 84 (1): 376-387. 2019.
  •  266
    Higher kurtz randomness
    with Bjørn Kjos-Hanssen, André Nies, and Frank Stephan
    Annals 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
  •  112
    Maximal pairs of c.e. reals in the computably Lipschitz degrees
    with Yun Fan
    Annals 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
  •  235
    Lowness and Π₂⁰ nullsets
    with Rod Downey, Andre Nies, and Rebecca Weber
    Journal 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
  •  94
    Maximal Chains in the Turing Degrees
    with C. T. Chong
    Journal 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
  •  74
    Measure Theory Aspects of Locally Countable Orderings
    Journal 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
  •  19
    On the hausdorff dimension of maximal chains and antichains of turing and hyperarithmetic degrees
    with Sirun Song
    Archive 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
  •  23
    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
  •  42
    Some more results on relativized Chaitin's Ω
    Annals of Pure and Applied Logic 176 (8): 103586. 2025.
  •  119
    Conference on Computability, Complexity and Randomness
    with Jinhe Chen and Decheng Ding
    Bulletin of Symbolic Logic 14 (4): 548-549. 2008.
  •  30
    Proceedings of the 14th and 15th Asian Logic Conferences (edited book)
    with Byunghan Kim, Jörg Brendle, Gyesik Lee, Fenrong Liu, R. Ramanujam, Shashi M. Srivastava, and Akito Tsuboi
    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
  •  91
    Eye-movement evidence of the time-course of attentional bias for threatening pictures in test-anxious students
    with Yunying Dong, Alain De Beuckelaer, and Renlai Zhou
    Cognition and Emotion 31 (4): 781-790. 2017.
  •  92
    Randomness in the higher setting
    with C. T. Chong
    Journal of Symbolic Logic 80 (4): 1131-1148. 2015.
  •  39
    A Reducibility Related To Being Hyperimmune-free
    with Frank Stephan
    Annals 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
  •  104
    The Kolmogorov complexity of random reals
    with Decheng Ding and Rodney Downey
    Annals 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
  •  109
    Lowness for genericity
    Archive 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
  •  113
    A new proof of Friedman's conjecture
    Bulletin 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
  •  120
    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
  •  151
    On the Definable Ideal Generated by Nonbounding C.E. Degrees
    with Yue Yang
    Journal 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