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1.
J Vet Behav ; 72: 18-27, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38435337

RESUMO

Successive Negative Contrast (SNC) occurs when there is a reduction in the quantity or quality of a reward that is expected according to the presence of contextual cues. This induces an emotional response of frustration that is similar to stress. While this phenomenon has been observed in several mammal species, findings in domestic dogs have been inconsistent, although this issue has strong relevance in dog training. The aim of this study was to assess the effects of Successive Negative Contrast in two responses that had already been studied in this species, but with an increase in the methodological rigor and variations in the experimental conditions to examine the generalizability of the phenomenon. To this end, experimental dogs experienced a pre-shift phase in which they received a high-value reward (liver), followed by a post-shift phase in which they obtained a low-value reward (dry dog food), and then a re-shift phase in which the high-value reward was available again. Control dogs received dry food in all phases. The results show a contrast effect on the behavior of following human pointing to obtain food (Study 1). On the contrary, there were no differences in problem solving behavior after the de- and re-evaluation of the reward during a non-social task (Study 2). The results support that Successive Negative Contrast is not a consistent phenomenon in pet dogs. It is possible that certain characteristics of dogs such as the great availability of high-value rewards in their daily lives could attenuate the effects of a reduction in incentive value.

2.
Anim Cogn ; 23(2): 337-350, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31832796

RESUMO

With very few exceptions, no coherent model of representing the self exists for nonhuman species. According to our hypothesis, understanding of the Self as an object' can also be found in a wide range of animals including the dog, a fast-moving terrestrial predator/scavenger, with highly developed senses and complex cognitive capacity. We tested companion dogs in three experiments in which they faced three different variations of the same physical challenge: passing through an opening in a wall. We predicted that if dogs are capable of representing their own body size, they will react differently when faced with adequate or too small openings. We found that dogs started to move towards and approached the too small openings with significantly longer latencies than the suitable ones; and upon reaching it, they did not try to get through the too small openings. In another experiment, the medium-size (still large enough) opening was approached with latencies that fell between the latencies measured in the cases of the very large or the too small openings. Having discussed the potential underlying mechanisms, we concluded that our results convincingly assume that dogs can represent their own body size in novel contexts.


Assuntos
Conscientização , Tamanho Corporal , Animais , Cães
3.
R Soc Open Sci ; 4(5): 170134, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28573021

RESUMO

Vocal expressions of emotions follow simple rules to encode the inner state of the caller into acoustic parameters, not just within species, but also in cross-species communication. Humans use these structural rules to attribute emotions to dog vocalizations, especially to barks, which match with their contexts. In contrast, humans were found to be unable to differentiate between playful and threatening growls, probably because single growls' aggression level was assessed based on acoustic size cues. To resolve this contradiction, we played back natural growl bouts from three social contexts (food guarding, threatening and playing) to humans, who had to rate the emotional load and guess the context of the playbacks. Listeners attributed emotions to growls according to their social contexts. Within threatening and playful contexts, bouts with shorter, slower pulsing growls and showing smaller apparent body size were rated to be less aggressive and fearful, but more playful and happy. Participants associated the correct contexts with the growls above chance. Moreover, women and participants experienced with dogs scored higher in this task. Our results indicate that dogs may communicate honestly their size and inner state in a serious contest situation, while manipulatively in more uncertain defensive and playful contexts.

4.
Mater Sci Eng C Mater Biol Appl ; 71: 465-472, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27987733

RESUMO

Prostate cancer (PCa) currently is the second most diagnosed cancer in men and the second most cause of cancer death after lung cancer in Western societies. This sets the necessity of modelling prostatic disorders to optimize a therapy against them. The conventional approach to investigating prostatic diseases is based on two-dimensional (2D) cell culturing. This method, however, does not provide a three-dimensional (3D) environment, therefore impeding a satisfying simulation of the prostate gland in which the PCa cells proliferate. Cryogel scaffolds represent a valid alternative to 2D culturing systems for studying the normal and pathological behavior of the prostate cells thanks to their 3D pore architecture that reflects more closely the physiological environment in which PCa cells develop. In this work the 3D morphology of three potential scaffolds for PCa cell culturing was investigated by means of synchrotron X-ray computed micro tomography (SXCµT) fitting the according requirements of high spatial resolution, 3D imaging capability and low dose requirements very well. In combination with mechanical tests, the results allowed identifying an optimal cryogel architecture, meeting the needs for a well-suited scaffold to be used for 3D PCa cell culture applications. The selected cryogel was then used for culturing prostatic lymph node metastasis (LNCaP) cells and subsequently, the presence of multi-cellular tumor spheroids inside the matrix was demonstrated again by using SXCµT.


Assuntos
Técnicas de Cultura de Células/métodos , Criogéis/química , Neoplasias da Próstata/metabolismo , Alicerces Teciduais/química , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/patologia
5.
Science ; 353(6303): 1030-1032, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27576923

RESUMO

During speech processing, human listeners can separately analyze lexical and intonational cues to arrive at a unified representation of communicative content. The evolution of this capacity can be best investigated by comparative studies. Using functional magnetic resonance imaging, we explored whether and how dog brains segregate and integrate lexical and intonational information. We found a left-hemisphere bias for processing meaningful words, independently of intonation; a right auditory brain region for distinguishing intonationally marked and unmarked words; and increased activity in primary reward regions only when both lexical and intonational information were consistent with praise. Neural mechanisms to separately analyze and integrate word meaning and intonation in dogs suggest that this capacity can evolve in the absence of language.


Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Cães/fisiologia , Cães/psicologia , Neurônios/fisiologia , Percepção da Fala/fisiologia , Animais , Encéfalo/citologia , Mapeamento Encefálico , Sinais (Psicologia) , Lateralidade Funcional , Idioma , Imageamento por Ressonância Magnética
6.
Hist Soz Forsch ; 23(1-2): 83-111, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-12178165

RESUMO

"John Hajnal's pathbreaking paper about the European marriage patterns and his household formation theory provoked high interest [among] researchers even far beyond the border of the historical demographic research. Examining them through the Hungarian sources we can say that both the declared factors and variables of household formation and their regional strength and territorial distribution cannot be interpreted unanimously and adequately with the rules established by John Hajnal. Maybe it is better not to think in universalistic regimes but, moreover, adapt a regional and temporal frame of reference."


Assuntos
Demografia , Estudos de Avaliação como Assunto , Características da Família , Geografia , Casamento , Modelos Teóricos , Países Desenvolvidos , Europa (Continente) , Europa Oriental , Hungria , População , Pesquisa
7.
Stat Szle ; 74(10): 855-63, 1996 Oct.
Artigo em Húngaro | MEDLINE | ID: mdl-12321661

RESUMO

PIP: "The study is an enlarged and annotated version of the lecture delivered at the 29th Itinerary Session on the History of Statistics, held in honour of the 125 year anniversary of the official statistical service (Balatonalmadi, 24 September 1992). The author analyses the history of the correlations of historical demography and official statistics from their beginnings up to our days. Then he touches upon the relationship of statistical, historical etc. education [in] universities and of historical demography. Practical aspects of the organization of science are also discussed through analysing the situation of various related institutions and scientific magazines. Finally the socio-political environment of historical demography is analysed." The focus is on Hungary. (EXCERPT)^ieng


Assuntos
Demografia , Características da População , Pesquisa , Países Desenvolvidos , Europa (Continente) , Europa Oriental , Hungria , Ciências Sociais
8.
Stat Szle ; 73(4-5): 375-91, 1995.
Artigo em Húngaro | MEDLINE | ID: mdl-12319610

RESUMO

"The author intends to show the growth...and development of Budapest's population during 100 years (1840-1941)." (SUMMARY IN ENG)


Assuntos
Dinâmica Populacional , População Urbana , Demografia , Países Desenvolvidos , Europa (Continente) , Europa Oriental , Hungria , População , Características da População
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