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1.
Arch Math Log ; 62(1-2): 207-223, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36687782

RESUMO

Lindström's Theorem characterizes first order logic as the maximal logic satisfying the Compactness Theorem and the Downward Löwenheim-Skolem Theorem. If we do not assume that logics are closed under negation, there is an obvious extension of first order logic with the two model theoretic properties mentioned, namely existential second order logic. We show that existential second order logic has a whole family of proper extensions satisfying the Compactness Theorem and the Downward Löwenheim-Skolem Theorem. Furthermore, we show that in the context of negation-less logics, positive logics, as we call them, there is no strongest extension of first order logic with the Compactness Theorem and the Downward Löwenheim-Skolem Theorem.

2.
Mem Cognit ; 50(5): 1048-1060, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34843083

RESUMO

Observing others performing an action can lead to false memories of self-performance - the observation-inflation effect. The action simulation hypothesis proposes that an action simulation caused by people's observation of an action is the key reason for this effect. Previous studies have inconsistent views of this hypothesis. In the present study, we re-examined the role of action simulation and discussed the key aspects of the mental processes associated with it. We examined the hypotheses that (a) the magnitude of the observation-inflation effect would decrease as the action simulation was impeded and (b) the magnitude of the observation-inflation effect would not be significantly different in conditions in which participants watched either a part of a video or a full video. The results are consistent with the hypotheses. This study provides strong evidence that action simulation influences the generation of observation-inflation effects and that the process is continuous and can refer to further action information.


Assuntos
Memória , Atividade Motora , Humanos
3.
Entropy (Basel) ; 24(3)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35327903

RESUMO

The II law of thermodynamics is most often given in three supposedly equivalent formulations: two Clausius (I and II) and one Kelvin. The most general and indisputable entropy formulation belongs to Clausius (II). The earlier Clausius I principle determines the natural direction heat flow between bodies at different temperatures. On the other hand, the Kelvin principle states that it is impossible to completely convert heat into work. The author argues that the Kelvin principle is a weaker statement (or more strictly non-equivalent) than the Clausius I principle, and the latter is a weaker statement than Carnot principle, which is equivalent to Clausius II principle. As a result, the Kelvin principle and the Clausius I principle are not exhaustive formulations of the II law of thermodynamics. At the same time, it turns out that the Carnot principle becomes such a formulation. Apart from providing a complete set of proof and disproof, the author, indicates where the methodological errors were made in the alleged proof of the equivalence of the Kelvin principle and both Clausius principles.

4.
Health Promot J Austr ; 32(1): 107-116, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31724778

RESUMO

ISSUE ADDRESSED: Considerable public effort has been directed at centre-based childcare as an early childhood education and care (ECEC) setting to promote healthy food-related behaviours in young children. However, in the real-world setting, best practice, evidence-based guidelines are not always well-translated into usual, day-to-day routines. This study aims to understand what factors influence the centre-based childcare cooks' food and nutrition decisions for children aged 2-5 years. METHODS: Semi-structured qualitative interviews were conducted with cooks in centre-based childcare using purposeful maximum variation sampling and data analysed thematically. RESULTS: Fourteen cooks were interviewed from 14 services across South Australia. Central to providing a healthy food environment was expert-led knowledge and training gained through the workplace over several years and the embodiment of the service's healthy food and nutrition policy, evidenced through menu planning to maintain a focus on healthy eating. Threatening these positive, routine practices and decisions were pressures to modify menus in response to increasing food allergies and changing cultural and family preferences, in the absence of ongoing relevant training and expertise at the system-level. CONCLUSIONS: Children in ECEC benefit from cooks' commitment to providing nutritious foods; however, the requirements to extend their role to respond to increasing demands without relevant system-level support and training puts the children at risk of not being exposed to health-promoting menus and possible errors in providing dietary modifications. ECEC cooks urgently need access to system-level support and training. SO WHAT?: Understanding and addressing the barriers experienced by cooks and the complexity of factors that inform their food-related decision-making will sustain the implementation of effective, healthy eating guidelines and nutrition practices in ECEC.


Assuntos
Creches , Serviços de Alimentação , Criança , Pré-Escolar , Promoção da Saúde , Humanos , Política Nutricional , Austrália do Sul
5.
Synthese ; 198(6): 5547-5575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720223

RESUMO

The aim of this article is to contribute to a better understanding of Frege's views on semantics and metatheory by looking at his take on several themes in nineteenth century geometry that were significant for the development of modern model-theoretic semantics. I will focus on three issues in which a central semantic idea, the idea of reinterpreting non-logical terms, gradually came to play a substantial role: the introduction of elements at infinity in projective geometry; the study of transfer principles, especially the principle of duality; and the use of counterexamples in independence arguments. Based on a discussion of these issues and how nineteenth century geometers reflected about them, I will then look into Frege's take on these matters. I conclude with a discussion of Frege's views and what they entail for the debate about his stance towards semantics and metatheory more generally.

6.
Cogn Process ; 21(2): 155-165, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32056028

RESUMO

The Mental Model concept has evolved from being a representation of reality to which we apply formal logic, to a type of logic with which we make decisions, learn, and adapt. This work uses bibliometric indicators to describe research on Mental Models from 1997 to 2017. The results show progressive growth since the late 1990s and a stationary trend starting in 2010. The existing research is dominated by the fields of individual and organizational psychology as well as education. Since 2007, a corpus of research (works that continue or are based on previous work) has been developed around the themes of memory, cognition, interpretation, and Johnson-Laird's work. In the late 2000s, another possible corpus emerged around team work. It is recommended to develop similar research in specific areas.


Assuntos
Bibliometria , Modelos Psicológicos , Cognição , Humanos , Lógica
7.
Proc Natl Acad Sci U S A ; 110(33): 13300-5, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23836659

RESUMO

Cantor proved in 1874 [Cantor G (1874) J Reine Angew Math 77:258-262] that the continuum is uncountable, and Hilbert's first problem asks whether it is the smallest uncountable cardinal. A program arose to study cardinal invariants of the continuum, which measure the size of the continuum in various ways. By Gödel [Gödel K (1939) Proc Natl Acad Sci USA 25(4):220-224] and Cohen [Cohen P (1963) Proc Natl Acad Sci USA 50(6):1143-1148], Hilbert's first problem is independent of ZFC (Zermelo-Fraenkel set theory with the axiom of choice). Much work both before and since has been done on inequalities between these cardinal invariants, but some basic questions have remained open despite Cohen's introduction of forcing. The oldest and perhaps most famous of these is whether " p = t," which was proved in a special case by Rothberger [Rothberger F (1948) Fund Math 35:29-46], building on Hausdorff [Hausdorff (1936) Fund Math 26:241-255]. In this paper we explain how our work on the structure of Keisler's order, a large-scale classification problem in model theory, led to the solution of this problem in ZFC as well as of an a priori unrelated open question in model theory.


Assuntos
Classificação/métodos , Matemática/métodos , Modelos Teóricos
8.
Polymers (Basel) ; 15(5)2023 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36904420

RESUMO

Generic polymer models capturing the chain connectivity and the non-bonded excluded-volume interactions between polymer segments can be classified into hard- and soft-core models depending on their non-bonded pair potential. Here we compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory, and found different behaviors of the soft-core models at large invariant degree of polymerization (IDP) depending on how IDP is varied. We also proposed an efficient numerical approach, which enables us to accurately solve the PRISM theory for chain lengths as large as 106.

9.
J R Soc Interface ; 20(202): 20230168, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37221863

RESUMO

Architecture with and from living trees (Baubotanik) is a promising approach to sustainable, climate-adapted construction. Shaping and grafting allows one to create resilient structures that combine the ecological performance and aesthetics of trees with the functions of buildings. In order to design and engineer such living structures, it is necessary to predict the growth of different tree segments, especially when trunks, branches or roots are bent and jointed into a complex inosculated network. To address this, we have developed a tool to forecast the relative girth growth of different segments in such structures based on topological skeletons, the pipe model theory and circuit analogy. We have validated our results with a set of (scaled) photographs of inosculated tree structures of the so-called 'Tree Circus', covering over 80 years of their growth. Our model has proven to predict the relative girth growth with sufficient accuracy for conceptual design purposes. So far, it does not allow the simulation of absolute growth in circumference over the course of time that is necessary to predict quantitative technical aspects, such as mechanical performance at a given time. We conclude by briefly outlining how this could be addressed in future research.


Assuntos
Aclimatação , Dendritos , Simulação por Computador , Raízes de Plantas , Esqueleto
10.
Plants (Basel) ; 12(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36987073

RESUMO

Faced with the environmental challenges posed by climate change, architects are creating nature-based solutions for urban areas, such as transforming living trees into artificial architectural structures. In this study, we have analyzed stem pairs of five tree species conjoined for more than eight years by measuring the stem diameters below and above the resulting inosculation and by calculating the respective diameter ratio. Our statistical analyses reveal that Platanus × hispanica and Salix alba stems do not differ significantly in diameter below inosculation. However, in contrast to P. × hispanica, the diameters of the conjoined stems above inosculation differ significantly in S. alba. We provide a binary decision tree based on diameter comparisons above and below inosculation as a straightforward tool for identifying the likelihood of full inosculation with water exchange. Moreover, we have compared branch junctions and inosculations by means of anatomical analyses, micro-computed tomography, and 3D reconstructions showing similarities in the formation of common annual rings that increase the capacity for water exchange. Due to the highly irregular cell arrangement in the center of the inosculations, cells cannot be assigned clearly to either of the stems. In contrast, cells in the center of branch junctions can always be attributed to one of the branches.

11.
Am J Transl Res ; 14(8): 5520-5528, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105053

RESUMO

OBJECTIVE: This study aimed to explore the role of Roy adaptation model (RAM)-based nursing diagnosis and implementation in regulating the sense of shame and improving the nursing outcomes of female patients with breast cancer. METHODS: The clinical data of 69 female patients with breast cancer treated in our hospital from October 2019 to October 2021 were retrospectively analyzed. Patients who received conventional care were included in a control group, and those who received RAM-based nursing were included in an observation group. Patients in both groups were evaluated for sense of shame, emotional state, psychological resilience, self-esteem, quality of recovery scores and complication rates. RESULTS: The scores of Perceived Devaluation and Discrimination Scale (PDD), Substance Use Stigma Mechanisms Scale (SUSMS) and Stigma Coping Scale (SCS) in the observation group were lower than those of the control group at the end of nursing (P < 0.05). The score of Hamilton Anxiety Rating Scale (HAMA) in the observation group was lower than that in the control group at the end of nursing (P < 0.05). The levels of mental toughness, mental strength, and optimism scores in the observation group were higher than those of the control group at the end of nursing (P < 0.05). The score of Rosenberg Self-Esteem Scale (SES) in the observation group was significantly higher than that of the control group at the end of nursing (P < 0.05). Psychosocial recovery, physical recovery, relationship with medical workers, marital relationship, and sexual function scores in the observation group were significantly lower than those in the control group at the end of nursing (P < 0.05). The incidence of complications was 5.71% in the observation group, lower than 23.53% in the control group (P < 0.05). CONCLUSION: RAM-based nursing diagnosis and implementation can significantly reduce patients' sense of shame and negative emotions, improve patients' psychological resilience, quality of recovery, and quality of life, and reduce complications for female patients with breast cancer.

12.
Front Plant Sci ; 13: 817792, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35356110

RESUMO

Trees adapt to their growing conditions by regulating the sizes of their parts and their relationships. For example, removal or death of adjacent trees increases the growing space and the amount of light received by the remaining trees enabling their crowns to expand. Knowledge about the effects of silvicultural practices on crown size and shape and also about the quality of branches affecting the shape of a crown is, however, still limited. Thus, the aim was to study the crown structure of individual Scots pine trees in forest stands with varying stem densities due to past forest management practices. Furthermore, we wanted to understand how crown and stem attributes and also tree growth affect stem area at the height of maximum crown diameter (SAHMC), which could be used as a proxy for tree growth potential. We used terrestrial laser scanning (TLS) to generate attributes characterizing crown size and shape. The results showed that increasing stem density decreased Scots pine crown size. TLS provided more detailed attributes for crown characterization compared with traditional field measurements. Furthermore, decreasing stem density increased SAHMC, and strong relationships (Spearman's correlations > 0.5) were found between SAHMC and crown and stem size and also stem growth. Thus, this study provided quantitative and more comprehensive characterization of Scots pine crowns and their growth potential. The combination of a traditional growth and yield study design and 3D characterization of crown architecture and growth potential can open up new research possibilities.

13.
Cogn Sci ; 45(4): e12961, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33873241

RESUMO

In two recent papers, Rose and Nichols present evidence in favor of the view that humans represent category essences in terms of a telos, such as honey-making, and not in terms of scientific essences, such as bee DNA. Here, I challenge their interpretation of the evidence and show that it is directly predicted by the main theory they seek to undermine. I argue that their results can be explained as instances of diagnostic reasoning about scientific essences.


Assuntos
Resolução de Problemas , Animais , Abelhas , Humanos
14.
Int J Epidemiol ; 50(2): 620-632, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33330936

RESUMO

BACKGROUND: Directed acyclic graphs (DAGs) are an increasingly popular approach for identifying confounding variables that require conditioning when estimating causal effects. This review examined the use of DAGs in applied health research to inform recommendations for improving their transparency and utility in future research. METHODS: Original health research articles published during 1999-2017 mentioning 'directed acyclic graphs' (or similar) or citing DAGitty were identified from Scopus, Web of Science, Medline and Embase. Data were extracted on the reporting of: estimands, DAGs and adjustment sets, alongside the characteristics of each article's largest DAG. RESULTS: A total of 234 articles were identified that reported using DAGs. A fifth (n = 48, 21%) reported their target estimand(s) and half (n = 115, 48%) reported the adjustment set(s) implied by their DAG(s). Two-thirds of the articles (n = 144, 62%) made at least one DAG available. DAGs varied in size but averaged 12 nodes [interquartile range (IQR): 9-16, range: 3-28] and 29 arcs (IQR: 19-42, range: 3-99). The median saturation (i.e. percentage of total possible arcs) was 46% (IQR: 31-67, range: 12-100). 37% (n = 53) of the DAGs included unobserved variables, 17% (n = 25) included 'super-nodes' (i.e. nodes containing more than one variable) and 34% (n = 49) were visually arranged so that the constituent arcs flowed in the same direction (e.g. top-to-bottom). CONCLUSION: There is substantial variation in the use and reporting of DAGs in applied health research. Although this partly reflects their flexibility, it also highlights some potential areas for improvement. This review hence offers several recommendations to improve the reporting and use of DAGs in future research.


Assuntos
Pesquisa , Viés , Causalidade , Fatores de Confusão Epidemiológicos , Interpretação Estatística de Dados , Humanos
15.
Health Informatics J ; 26(4): 2637-2659, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32567461

RESUMO

Despite the benefits promised by mobile health, the introduction of these solutions is often met with resistance from various stakeholders. This article adopts a shared mental model approach to unearth the current perceptions, concerns, and mentalities of key stakeholders engaged in the provision of healthcare in Nigeria. These include policy makers, academics, healthcare professionals, and health information systems developers. Interviews and focus groups were used to examine stakeholders' views across three mental models: (1) the technology, (2) processes, and (3) the team. Our investigations reveal disparities in stakeholders' existing mental models and their perceptions of the proposed mobile health solution. We argue that fostering a common understanding of mobile health, as well as elucidating an improved understanding of processes and team behaviours, will mitigate the risk of resistance among stakeholders involved in the design and delivery of community healthcare services and culminate in a positive attitude towards new mobile health solutions among these stakeholders. We highlight the need to enhance communication and training from national to rural levels to promote complementary mental models and positively influence team performance.


Assuntos
Atenção à Saúde , Telemedicina , Humanos , Modelos Psicológicos , Nigéria , Pesquisa Qualitativa
16.
Soft comput ; 23(7): 2177-2186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30956543

RESUMO

This paper is a contribution to graded model theory, in the context of mathematical fuzzy logic. We study characterizations of classes of graded structures in terms of the syntactic form of their first-order axiomatization. We focus on classes given by universal and universal-existential sentences. In particular, we prove two amalgamation results using the technique of diagrams in the setting of structures valued on a finite MTL-algebra, from which analogues of the Los-Tarski and the Chang-Los-Suszko preservation theorems follow.

17.
R Soc Open Sci ; 5(7): 171448, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30109039

RESUMO

Conceiving of stimuli and responses as causes and effects, and assuming that rats acquire representational models of causal relations from Pavlovian procedures, previous work by causal model theory proponents attempted to train rat subjects to represent stimulus A as a cause of both stimulus B and food. By these assumptions, with formal help from Bayesian networks, self-production of stimulus B should reduce expectation of alternative causes, including stimulus A, and their effects, including food. Reduced feeder-directed responding to stimulus B when self-produced has been taken as evidence for a general causal reasoning capacity among rats involving mental maps of causal relations. Critics have rejoined that response competition can explain these effects. The present research replicates the key effect, but uses continuous and finer-grained measurement of a broader range of behaviours. Behaviours not recorded in previous studies contradict both prior explanations. Even results cited in support of these explanations, when measured in finer detail and continuously over longer periods, show patterns not expected by either view, but supportive of a specific-process approach with attention to motivational factors. Still, the abstract prediction from Bayesian networks holds, providing a potentially complementary normative analysis. Behaviour systems theory provides firmer framing for such theories than representational-map alternatives.

18.
Front Robot AI ; 5: 76, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-33500955

RESUMO

This paper shows how methods from statistical relational learning can be used to address problems in grammatical inference using model-theoretic representations of strings. These model-theoretic representations are the basis of representing formal languages logically. Conventional representations include a binary relation for order and unary relations describing mutually exclusive properties of each position in the string. This paper presents experiments on the learning of formal languages, and their stochastic counterparts, with unconventional models, which relax the mutual exclusivity condition. Unconventional models are motivated by domain-specific knowledge. Comparison of conventional and unconventional word models shows that in the domains of phonology and robotic planning and control, Markov Logic Networks With unconventional models achieve better performance and less runtime with smaller networks than Markov Logic Networks With conventional models.

19.
Front Psychol ; 5: 1303, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25505432

RESUMO

Cognitive psychological research focuses on causal learning and reasoning while cognitive anthropological and social science research tend to focus on systems of beliefs. Our aim was to explore how these two types of research can inform each other. Cognitive psychological theories (causal model theory and causal Bayes nets) were used to derive predictions for systems of causal beliefs. These predictions were then applied to lay theories of depression as a specific test case. A systematic literature review on causal beliefs about depression was conducted, including original, quantitative research. Thirty-six studies investigating 13 non-Western and 32 Western cultural groups were analyzed by classifying assumed causes and preferred forms of treatment into common categories. Relations between beliefs and treatment preferences were assessed. Substantial agreement between cultural groups was found with respect to the impact of observable causes. Stress was generally rated as most important. Less agreement resulted for hidden, especially supernatural causes. Causal beliefs were clearly related to treatment preferences in Western groups, while evidence was mostly lacking for non-Western groups. Overall predictions were supported, but there were considerable methodological limitations. Pointers to future research, which may combine studies on causal beliefs with experimental paradigms on causal reasoning, are given.

20.
Acta Psychol (Amst) ; 153: 95-106, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25463549

RESUMO

A number of heuristic-based hypotheses have been proposed to explain how people solve syllogisms with automatic processes. In particular, the matching heuristic employs the congruency of the quantifiers in a syllogism­by matching the quantifier of the conclusion with those of the two premises. When the heuristic leads to an invalid conclusion, successful solving of these conflict problems requires the inhibition of automatic heuristic processing. Accordingly, if the automatic processing were based on processing the set of quantifiers, no semantic contents would be inhibited. The mental model theory, however, suggests that people reason using mental models, which always involves semantic processing. Therefore, whatever inhibition occurs in the processing implies the inhibition of the semantic contents. We manipulated the validity of the syllogism and the congruency of the quantifier of its conclusion with those of the two premises according to the matching heuristic. A subsequent lexical decision task (LDT) with related words in the conclusion was used to test any inhibition of the semantic contents after each syllogistic evaluation trial. In the LDT, the facilitation effect of semantic priming diminished after correctly solved conflict syllogisms (match-invalid or mismatch-valid), but was intact after no-conflict syllogisms. The results suggest the involvement of an inhibitory mechanism of semantic contents in syllogistic reasoning when there is a conflict between the output of the syntactic heuristic and actual validity. Our results do not support a uniquely syntactic process of syllogistic reasoning but fit with the predictions based on mental model theory.


Assuntos
Função Executiva/fisiologia , Inibição Psicológica , Lógica , Memória de Curto Prazo/fisiologia , Pensamento/fisiologia , Adulto , Conflito Psicológico , Feminino , Humanos , Masculino , Adulto Jovem
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