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When people seek to understand concepts from an incomplete set of examples and counterexamples, there is usually an exponentially large number of classification rules that can correctly classify the observed data, depending on which features of the examples are used to construct these rules. A mechanistic approximation of human concept-learning should help to explain how humans prefer some rules over others when there are many that can be used to correctly classify the observed data. Here, we exploit the tools of propositional logic to develop an experimental framework that controls the minimal rules that are simultaneously consistent with the presented examples. For example, our framework allows us to present participants with concepts consistent with a disjunction and also with a conjunction, depending on which features are used to build the rule. Similarly, it allows us to present concepts that are simultaneously consistent with two or more rules of different complexity and using different features. Importantly, our framework fully controls which minimal rules compete to explain the examples and is able to recover the features used by the participant to build the classification rule, without relying on supplementary attention-tracking mechanisms (e.g. eye-tracking). We exploit our framework in an experiment with a sequence of such competitive trials, illustrating the emergence of various transfer effects that bias participants’ prior attention to specific sets of features during learning. Fil: Abriola, Sergio Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina Fil: Tano, Pablo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Romano, Sergio Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina Fil: Figueira, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina

© 2021 by the authors., Early diagnosis of pediatric cancer is key for adequate patient management and improved outcome. Although multiparameter flow cytometry (MFC) has proven of great utility in the diagnosis and classification of hematologic malignancies, its application to non-hematopoietic pediatric tumors remains limited. Here we designed and prospectively validated a new single eight-color antibody combination—solid tumor orientation tube, STOT—for diagnostic screening of pediatric cancer by MFC. A total of 476 samples (139 tumor mass, 138 bone marrow, 86 lymph node, 58 peripheral blood, and 55 other body fluid samples) from 296 patients with diagnostic suspicion of pediatric cancer were analyzed by MFC vs. conventional diagnostic procedures. STOT was designed after several design–test–evaluate–redesign cycles based on a large panel of monoclonal antibody combinations tested on 301 samples. In its final version, STOT consists of a single 8-color/12-marker antibody combination (CD99-CD8/numyogenin/CD4-EpCAM/CD56/GD2/smCD3-CD19/cyCD3-CD271/CD45). Prospective validation of STOT in 149 samples showed concordant results with the patient WHO/ICCC-3 diagnosis in 138/149 cases (92.6%). These included: 63/63 (100%) reactive/disease-free samples, 43/44 (98%) malignant and 4/4 (100%) benign non-hematopoietic tumors together with 28/38 (74%) leukemia/lymphoma cases; the only exception was Hodgkin lymphoma that required additional markers to be stained. In addition, STOT allowed accurate discrimination among the four most common subtypes of malignant CD45− CD56++ non-hematopoietic solid tumors: 13/13 (GD2++ numyogenin− CD271−/+ nuMyoD1− CD99− EpCAM−) neuroblastoma samples, 5/5 (GD2− numyogenin++ CD271++ nuMyoD1++ CD99−/+ EpCAM−) rhabdomyosarcomas, 2/2 (GD2−/+ numyogenin− CD271+ nuMyoD1− CD99+ EpCAM−) Ewing sarcoma family of tumors, and 7/7 (GD2− numyogenin− CD271+ nuMyoD1− CD99− EpCAM+) Wilms tumors. In summary, here we designed and validated a new standardized antibody combination and MFC assay for diagnostic screening of pediatric solid tumors that might contribute to fast and accurate diagnostic orientation and classification of pediatric cancer in routine clinical practice., This research was funded by the EuroFlow Consortium; Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro, Brazil (FAPERJ), numbers: E26/110.105/2014, E-26/010.101259/2018, and E26/102.191/2013; grant from Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brasília, Brazil (CNPQ), Brasília, Brazil, numbers: 303765/2018-6, 409440/2016-7, and 400194/2014-7; and Instituto Desiderata/Chevron, Rio de Janeiro, Brazil, grant “Actions to improve pediatric cancer assistance in RJ”; the EuroFlow Consortium (grant LSHB-CT-2006-018708); Centro de Investigación Biomédica en Red de Cáncer (CIBER-ONC; Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain and FONDOS FEDER), numbers: CB16/12/00400, CB16/12/00233, CB16/12/00369, CB16/12/00489 and CB16/12/00480; grant from Bilateral Cooperation Program between Coordenação de Aperfeiçoamento de Pessoal de Nível Superior-CAPES (Brasília/Brazil) and Dirección General de Políticas Universitárias (DGPU)-Ministério de Educación, Cultura y Deportes (Madrid/Spain) number DGPU 311/15.

When he visited China in June 1989 Michail Gorbachev, Secretary General of the PCUS and President of the Soviet Union, had two objectives. He wanted to see for himself how Deng Xiaoping's reforms were transforming the country and hoped to patch up the political and ideological strains that had upset relations between Moscow and Beijing, from the withdrawal of Soviet advisors at the time of Krushev to the harsh military clashes over the Ussuri in 1968 and the different positions taken by the two countries during the Afghan crisis of 1979. At the same time, the Soviet President tried to explain his perestroika to Deng. The intentions were reasonable, but the climate changed when the Soviet leader's presence in Beijing had the effect of enthusing the young people of the capital. While the Chinese leaders were gradually introducing the rules of the market into the economy, Gorbachev spoke of "glasnost" and seemed determined to change those of the political system. As soon as the Soviets left Beijing to return to their homeland, several thousand young Chinese began to meet in Tiananmen Square to demand democratic reforms. From that moment the Soviet leader ceased to be a possible model for China and his fall in December 1991 showed the Chinese leadership that the reform attempted by Moscow was a risk to avoid. I believe that this explains why the date of 3 June 2019 was awaited by Xi Jinping, President of the People's Republic of China, with some apprehension. [Continues]

Recent approaches to human concept learning have successfully combined the power of symbolic, infinitely productive rule systems and statistical learning to explain our ability to learn new concepts from just a few examples. The aim of most of these studies is to reveal the underlying language structuring these representations and providing a general substrate for thought. However, describing a model of thought that is fixed once trained is against the extensive literature that shows how experience shapes concept learning. Here, we ask about the plasticity of these symbolic descriptive languages. We perform a concept learning experiment that demonstrates that humans can change very rapidly the repertoire of symbols they use to identify concepts, by compiling expressions that are frequently used into new symbols of the language. The pattern of concept learning times is accurately described by a Bayesian agent that rationally updates the probability of compiling a new expression according to how useful it has been to compress concepts so far. By portraying the language of thought as a flexible system of rules, we also highlight the difficulties to pin it down empirically. Fil: Tano, Pablo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina Fil: Romano, Sergio Gaston. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina Fil: Sigman, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Torcuato Di Tella; Argentina. Universidad Nebrija; España Fil: Salles, Alejo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Calculo. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Calculo; Argentina Fil: Figueira, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Computación; Argentina

Probabilistic proposals of Language of Thoughts (LoTs) can explain learning across different domains as statistical inference over a compositionally structured hypothesis space. While frameworks may differ on how a LoT may be implemented computationally, they all share the property that they are built from a set of atomic symbols and rules by which these symbols can be combined. In this work we propose an extra validation step for the set of atomic productions defined by the experimenter. It starts by expanding the defined LoT grammar for the cognitive domain with a broader set of arbitrary productions and then uses Bayesian inference to prune the productions from the experimental data. The result allows the researcher to validate that the resulting grammar still matches the intuitive grammar chosen for the domain. We then test this method in the language of geometry, a specific LoT model for geometrical sequence learning. Finally, despite the fact of the geometrical LoT not being a universal (i.e. Turing-complete) language, we show an empirical relation between a sequence’s probability and its complexity consistent with the theoretical relationship for universal languages described by Levin’s Coding Theorem. Fil: Romano, Sergio Gaston. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina Fil: Salles, Alejo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo; Argentina Fil: Amalric, Marie. Université Paris Sud; Francia. Université Paris-Saclay; Francia. Institut National de la Santé et de la Recherche Médicale; Francia Fil: Dehaene, Stanislas. Université Paris-Saclay; Francia. Institut National de la Santé et de la Recherche Médicale; Francia. Université Paris Sud; Francia Fil: Sigman, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Torcuato Di Tella; Argentina Fil: Figueira, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; Argentina

Probabilistic proposals of Language of Thoughts (LoTs) can explain learning across different domains as statistical inference over a compositionally structured hypothesis space. While frameworks may differ on how a LoT may be implemented computationally, they all share the property that they are built from a set of atomic symbols and rules by which these symbols can be combined. In this work we show how the set of productions of a LoT grammar can be effectively selected from a broad repertoire of possible productions by an inferential process starting from experimental data. We then test this method in the language of geometry, a specific LoT model (Amalric et al., 2017). Finally, despite the fact of the geometrical LoT not being a universal (i.e. Turing-complete) language, we show an empirical relation between a sequence’s probability and its complexity consistent with the theoretical relationship for universal languages described by Levin’s Coding Theorem.

In this paper Ambassador Romano reflects on the principal changes that have occurred in the orientation of Italian foreign policy (the alliance with the USA, relations with Europe, Russia, the Balkans, the Middle East) over the past decade, assessing and evaluating the effectiveness of the innovations made during the Berlusconi governments.

Socioeconomic status (SES) is a determinant of outcome in various types of cancer. The aim of this study is to analyze the impact of the SES in Hodgkin's lymphoma (HL). From 2001 to 2005, 194 consecutive patients were prospectively followed in 5 institutions. Patients answered a questionnaire with a set of items used to determine the SES, and were then divided in 2 groups according to their SES score. There were 151 patients (78%) with a higher SES and 43 patients (22%) with a lower SES. The complete remission (CR) rate was 82%. Patients with a higher SES had a higher CR rate than those with a lower SES (85 vs. 72%, crude odds ratio = 2.27, p = 0.046). A lower SES and the performance status >1 were independently associated with a trend towards a lower CR, even when controlled for the other covariables of interest. Ten patients (5%) died during treatment. Death during treatment was associated with a lower SES (16 vs. 2%, p = 0.001), a performance status >1 (p < 0.0001), a lower lymphocyte count (p = 0.012) and weakly with a lower albumin level (p = 0.065). With a median follow-up of 1.7 years, a higher SES was associated with a better 2-year overall survival (93 vs. 79%, p = 0.01). In underprivileged countries, patients with a lower SES require a more careful monitoring during treatment, possibly with specific support measures. Regimens more intense than doxorubicin, bleomycin, vinblastine and dacarbazine could pose a prohibitive risk of complications in this group of patients. © 2006 Wiley-Liss, Inc.