Pub Date : 2026-02-02DOI: 10.1016/j.apal.2026.103729
Karim Khanaki
We present several new characterizations of IP (the independence property) and SOP (the strict order property) for continuous first-order logic and explore their connections to functional analysis and Banach space theory. Furthermore, we propose new dividing lines for unstable theories by examining subclasses of Baire-1 functions. We also explain why one should not expect a perfect analogue of Shelah's theorem—namely, that a theory is unstable if and only if it has IP or SOP—to hold for real-valued logics, particularly in the context of continuous logic.
{"title":"On classification of continuous first order theories","authors":"Karim Khanaki","doi":"10.1016/j.apal.2026.103729","DOIUrl":"10.1016/j.apal.2026.103729","url":null,"abstract":"<div><div>We present several new characterizations of <em>IP</em> (the independence property) and <em>SOP</em> (the strict order property) for continuous first-order logic and explore their connections to functional analysis and Banach space theory. Furthermore, we propose new dividing lines for unstable theories by examining subclasses of Baire-1 functions. We also explain why one should not expect a perfect analogue of Shelah's theorem—namely, that a theory is unstable if and only if it has <em>IP</em> or <em>SOP</em>—to hold for real-valued logics, particularly in the context of continuous logic.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 7","pages":"Article 103729"},"PeriodicalIF":0.6,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146116732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1016/j.apal.2026.103726
Kristóf Kanalas
We study positively closed and strongly positively closed topos-valued models of coherent theories. Positively closed is a global notion (it is defined in terms of all possible outgoing homomorphisms), while strongly positively closed is a local notion (it only concerns the definable sets inside the model). For Set-valued models of coherent theories they coincide.
We prove that if for a complete Boolean algebra, then positively closed but not strongly positively closed -valued models of coherent theories exist, yet, there is an alternative local property which characterizes positively closed -valued models.
A large part of our discussion is given in the context of infinite quantifier geometric logic, dealing with the fragment where κ is weakly compact.
{"title":"Positively closed Sh(B)-valued models","authors":"Kristóf Kanalas","doi":"10.1016/j.apal.2026.103726","DOIUrl":"10.1016/j.apal.2026.103726","url":null,"abstract":"<div><div>We study positively closed and strongly positively closed topos-valued models of coherent theories. Positively closed is a global notion (it is defined in terms of all possible outgoing homomorphisms), while strongly positively closed is a local notion (it only concerns the definable sets inside the model). For <strong>Set</strong>-valued models of coherent theories they coincide.</div><div>We prove that if <span><math><mi>E</mi><mo>=</mo><mi>S</mi><mi>h</mi><mo>(</mo><mi>B</mi><mo>,</mo><msub><mrow><mi>τ</mi></mrow><mrow><mi>c</mi><mi>o</mi><mi>h</mi></mrow></msub><mo>)</mo></math></span> for a complete Boolean algebra, then positively closed but not strongly positively closed <span><math><mi>E</mi></math></span>-valued models of coherent theories exist, yet, there is an alternative local property which characterizes positively closed <span><math><mi>E</mi></math></span>-valued models.</div><div>A large part of our discussion is given in the context of infinite quantifier geometric logic, dealing with the fragment <span><math><msubsup><mrow><mi>L</mi></mrow><mrow><mi>κ</mi><mi>κ</mi></mrow><mrow><mi>g</mi></mrow></msubsup></math></span> where <em>κ</em> is weakly compact.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 6","pages":"Article 103726"},"PeriodicalIF":0.6,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146079688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-12DOI: 10.1016/j.apal.2026.103724
Marcin Michalski, Robert Rałowski, Szymon Żeberski
We work in the Cantor space . The results of the paper adhere to the following pattern. Let and T be a perfect, uniformly perfect or Silver tree. Then for every there exists of the same kind as T such that for each . We also prove weaker statements for splitting trees. For the case we also provide a simple characterization of a basis of . We use these results to prove that the algebraic sum of a generalized Luzin set and a generalized Sierpiński set belongs to and , provided that is a regular cardinal.
{"title":"On algebraic sums, trees and ideals in the Cantor space","authors":"Marcin Michalski, Robert Rałowski, Szymon Żeberski","doi":"10.1016/j.apal.2026.103724","DOIUrl":"10.1016/j.apal.2026.103724","url":null,"abstract":"<div><div>We work in the Cantor space <span><math><msup><mrow><mn>2</mn></mrow><mrow><mi>ω</mi></mrow></msup></math></span>. The results of the paper adhere to the following pattern. Let <span><math><mi>I</mi><mo>∈</mo><mo>{</mo><mi>M</mi><mo>,</mo><mi>N</mi><mo>,</mo><mi>M</mi><mo>∩</mo><mi>N</mi><mo>,</mo><mi>E</mi><mo>}</mo></math></span> and <em>T</em> be a perfect, uniformly perfect or Silver tree. Then for every <span><math><mi>A</mi><mo>∈</mo><mi>I</mi></math></span> there exists <span><math><msup><mrow><mi>T</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>⊆</mo><mi>T</mi></math></span> of the same kind as <em>T</em> such that <span><math><mi>A</mi><mo>+</mo><munder><munder><mrow><mo>[</mo><msup><mrow><mi>T</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>]</mo><mo>+</mo><mo>[</mo><msup><mrow><mi>T</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>]</mo><mo>+</mo><mo>…</mo><mo>+</mo><mo>[</mo><msup><mrow><mi>T</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>]</mo></mrow><mo>︸</mo></munder><mrow><mi>n</mi><mtext>–times</mtext></mrow></munder><mo>∈</mo><mi>I</mi></math></span> for each <span><math><mi>n</mi><mo>∈</mo><mi>ω</mi></math></span>. We also prove weaker statements for splitting trees. For the case <span><math><mi>E</mi></math></span> we also provide a simple characterization of a basis of <span><math><mi>E</mi></math></span>. We use these results to prove that the algebraic sum of a generalized Luzin set and a generalized Sierpiński set belongs to <span><math><msub><mrow><mi>u</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>v</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>, provided that <span><math><mi>c</mi></math></span> is a regular cardinal.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 6","pages":"Article 103724"},"PeriodicalIF":0.6,"publicationDate":"2026-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146024445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-08DOI: 10.1016/j.apal.2026.103722
Lorenzo Notaro
We study the join-semilattice of constructibility real degrees in the side-by-side Sacks model, i.e., the model of set theory obtained by forcing with a countable-support product of infinitely many Sacks forcings over the constructible universe. In particular, we prove that in the side-by-side Sacks model the join-semilattice of constructibility real degrees is rigid, i.e., it does not have non-trivial automorphisms.
{"title":"Constructibility real degrees in the side-by-side Sacks model","authors":"Lorenzo Notaro","doi":"10.1016/j.apal.2026.103722","DOIUrl":"10.1016/j.apal.2026.103722","url":null,"abstract":"<div><div>We study the join-semilattice of constructibility real degrees in the side-by-side Sacks model, i.e., the model of set theory obtained by forcing with a countable-support product of infinitely many Sacks forcings over the constructible universe. In particular, we prove that in the side-by-side Sacks model the join-semilattice of constructibility real degrees is rigid, i.e., it does not have non-trivial automorphisms.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103722"},"PeriodicalIF":0.6,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-08DOI: 10.1016/j.apal.2026.103723
Yifan Hu , Ruihuan Mao , Guozhen Shen
A set A is dually Dedekind finite if every surjection from A onto A is injective; otherwise, A is dually Dedekind infinite. An amorphous set is an infinite set that cannot be partitioned into two infinite subsets. A strictly amorphous set is an amorphous set in which every partition has only finitely many non-singleton blocks. It is proved consistent with (i.e., Zermelo–Fraenkel set theory without the axiom of choice) that there exists an amorphous set A whose power set is dually Dedekind infinite, which gives a negative solution to a question proposed by Truss (1974) [13]. Nevertheless, we prove in that, for all strictly amorphous sets A and all natural numbers n, is dually Dedekind finite, which generalizes a result of Goldstern.
{"title":"Amorphous sets and dual Dedekind finiteness","authors":"Yifan Hu , Ruihuan Mao , Guozhen Shen","doi":"10.1016/j.apal.2026.103723","DOIUrl":"10.1016/j.apal.2026.103723","url":null,"abstract":"<div><div>A set <em>A</em> is dually Dedekind finite if every surjection from <em>A</em> onto <em>A</em> is injective; otherwise, <em>A</em> is dually Dedekind infinite. An amorphous set is an infinite set that cannot be partitioned into two infinite subsets. A strictly amorphous set is an amorphous set in which every partition has only finitely many non-singleton blocks. It is proved consistent with <span><math><mi>ZF</mi></math></span> (i.e., Zermelo–Fraenkel set theory without the axiom of choice) that there exists an amorphous set <em>A</em> whose power set <span><math><mi>P</mi><mo>(</mo><mi>A</mi><mo>)</mo></math></span> is dually Dedekind infinite, which gives a negative solution to a question proposed by Truss (1974) <span><span>[13]</span></span>. Nevertheless, we prove in <span><math><mi>ZF</mi></math></span> that, for all strictly amorphous sets <em>A</em> and all natural numbers <em>n</em>, <span><math><mi>P</mi><msup><mrow><mo>(</mo><mi>A</mi><mo>)</mo></mrow><mrow><mi>n</mi></mrow></msup></math></span> is dually Dedekind finite, which generalizes a result of Goldstern.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 6","pages":"Article 103723"},"PeriodicalIF":0.6,"publicationDate":"2026-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145950127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-07DOI: 10.1016/j.apal.2025.103717
Alan Dow , Raúl Figueroa-Sierra , Osvaldo Guzmán , Michael Hrušák
We prove that there is an ideal on ω that is not Katětov below nwd and does not have restrictions above . We also prove that in the Laver model every tall P-ideal is Katětov-Blass above and that it is consistent that every Q+ ideal is meager.
{"title":"The category dichotomy for ideals","authors":"Alan Dow , Raúl Figueroa-Sierra , Osvaldo Guzmán , Michael Hrušák","doi":"10.1016/j.apal.2025.103717","DOIUrl":"10.1016/j.apal.2025.103717","url":null,"abstract":"<div><div>We prove that there is an ideal on <em>ω</em> that is not Katětov below <span>nwd</span> and does not have restrictions above <span><math><mi>ED</mi></math></span>. We also prove that in the Laver model every tall <span>P</span>-ideal is Katětov-Blass above <span><math><msub><mrow><mi>ED</mi></mrow><mrow><mtext>fin</mtext></mrow></msub></math></span> and that it is consistent that every <span>Q</span><sup>+</sup> ideal is meager.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103717"},"PeriodicalIF":0.6,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-07DOI: 10.1016/j.apal.2026.103721
Osvaldo Guzmán , Francisco Santiago Nieto-de la Rosa
We analyze conditions to preserve with forcing multiple gaps, define conditions to ensure their existence, and study the minimal size of specific type of gaps.
分析了强制多间隙的保存条件,定义了保证多间隙存在的条件,研究了特定类型间隙的最小尺寸。
{"title":"Preserving and constructing multiple gaps","authors":"Osvaldo Guzmán , Francisco Santiago Nieto-de la Rosa","doi":"10.1016/j.apal.2026.103721","DOIUrl":"10.1016/j.apal.2026.103721","url":null,"abstract":"<div><div>We analyze conditions to preserve with forcing multiple gaps, define conditions to ensure their existence, and study the minimal size of specific type of gaps.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103721"},"PeriodicalIF":0.6,"publicationDate":"2026-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-02DOI: 10.1016/j.apal.2025.103707
Yutong Duan, Joel Nagloo
Let be distinct non-constant and non-degenerate solutions of the classical Lotka-Volterra system where . We show that if d and b are linearly independent over , then the solutions are algebraically independent over , that is . As a main part of the proof, we show that the set defined by the system in universal differential fields, with d and b linearly independent over , is strongly minimal and geometrically trivial. Our techniques also allows us to obtain partial results for some of the more general 2d-Lotka-Volterra system.
{"title":"Algebraic independence of the solutions of the classical Lotka-Volterra system","authors":"Yutong Duan, Joel Nagloo","doi":"10.1016/j.apal.2025.103707","DOIUrl":"10.1016/j.apal.2025.103707","url":null,"abstract":"<div><div>Let <span><math><mo>(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><msub><mrow><mi>y</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>)</mo><mo>,</mo><mo>…</mo><mo>,</mo><mo>(</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>,</mo><msub><mrow><mi>y</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo></math></span> be distinct non-constant and non-degenerate solutions of the classical Lotka-Volterra system<span><span><span><math><msup><mrow><mi>x</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>=</mo><mi>a</mi><mi>x</mi><mi>y</mi><mo>+</mo><mi>b</mi><mi>x</mi><mspace></mspace><msup><mrow><mi>y</mi></mrow><mrow><mo>′</mo></mrow></msup><mo>=</mo><mi>c</mi><mi>x</mi><mi>y</mi><mo>+</mo><mi>d</mi><mi>y</mi></math></span></span></span> where <span><math><mi>a</mi><mo>,</mo><mi>b</mi><mo>,</mo><mi>c</mi><mo>,</mo><mi>d</mi><mo>∈</mo><mi>C</mi><mo>∖</mo><mo>{</mo><mn>0</mn><mo>}</mo></math></span>. We show that if <em>d</em> and <em>b</em> are linearly independent over <span><math><mi>Q</mi></math></span>, then the solutions are algebraically independent over <span><math><mi>C</mi></math></span>, that is <span><math><mi>t</mi><mi>r</mi><mo>.</mo><mi>d</mi><mi>e</mi><msub><mrow><mi>g</mi></mrow><mrow><mi>C</mi></mrow></msub><mi>C</mi><mo>(</mo><msub><mrow><mi>x</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><msub><mrow><mi>y</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>,</mo><mo>…</mo><mo>,</mo><msub><mrow><mi>x</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>,</mo><msub><mrow><mi>y</mi></mrow><mrow><mi>n</mi></mrow></msub><mo>)</mo><mo>=</mo><mn>2</mn><mi>n</mi></math></span>. As a main part of the proof, we show that the set defined by the system in universal differential fields, with <em>d</em> and <em>b</em> linearly independent over <span><math><mi>Q</mi></math></span>, is strongly minimal and geometrically trivial. Our techniques also allows us to obtain partial results for some of the more general 2<em>d</em>-Lotka-Volterra system.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103707"},"PeriodicalIF":0.6,"publicationDate":"2026-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145926009","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-22DOI: 10.1016/j.apal.2025.103706
Max Illmer, Tim Netzer
We give a sufficient condition for a model theoretic structure B to ‘inherit’ quantifier elimination from another structure A. This yields an alternative proof of one of the main results from [8], namely quantifier elimination for certain matrix rings. The original proof uses model theory, and while it is very elegant and insightful, the proof we propose is much shorter and provides a constructive algorithm.
{"title":"Constructive quantifier elimination with a focus on matrix rings","authors":"Max Illmer, Tim Netzer","doi":"10.1016/j.apal.2025.103706","DOIUrl":"10.1016/j.apal.2025.103706","url":null,"abstract":"<div><div>We give a sufficient condition for a model theoretic structure <em>B</em> to ‘inherit’ quantifier elimination from another structure <em>A</em>. This yields an alternative proof of one of the main results from <span><span>[8]</span></span>, namely quantifier elimination for certain matrix rings. The original proof uses model theory, and while it is very elegant and insightful, the proof we propose is much shorter and provides a constructive algorithm.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103706"},"PeriodicalIF":0.6,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-12-16DOI: 10.1016/j.apal.2025.103705
Yayi Fu
Using a result in [6] and the proof of [2, Theorem 1.1], we show that there is such that for any finite graph G with VC-dimension ≤2, G has a clique or an anti-clique of size . We also show that the Erdős-Hajnal property for graphs with VC-dimension 1 can be proved using the δ-dimension technique in [4], and we show that when E is a definable symmetric binary relation, [4, Theorem 1.3] can be proved without using Shelah's 2-rank.
{"title":"A note on Erdős-Hajnal property for graphs with VC dimension ≤2","authors":"Yayi Fu","doi":"10.1016/j.apal.2025.103705","DOIUrl":"10.1016/j.apal.2025.103705","url":null,"abstract":"<div><div>Using a result in <span><span>[6]</span></span> and the proof of <span><span>[2, Theorem 1.1]</span></span>, we show that there is <span><math><mi>γ</mi><mo>></mo><mn>0</mn></math></span> such that for any finite graph <em>G</em> with VC-dimension ≤2, <em>G</em> has a clique or an anti-clique of size <span><math><mo>≥</mo><mo>|</mo><mi>G</mi><msup><mrow><mo>|</mo></mrow><mrow><mi>γ</mi></mrow></msup></math></span>. We also show that the Erdős-Hajnal property for graphs with VC-dimension 1 can be proved using the <strong><em>δ</em></strong>-dimension technique in <span><span>[4]</span></span>, and we show that when <em>E</em> is a definable symmetric binary relation, <span><span>[4, Theorem 1.3]</span></span> can be proved without using Shelah's 2-rank.</div></div>","PeriodicalId":50762,"journal":{"name":"Annals of Pure and Applied Logic","volume":"177 5","pages":"Article 103705"},"PeriodicalIF":0.6,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145790897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}