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1.
Lang Resour Eval ; 57(1): 415-448, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35125984

RESUMO

This paper presents the ParlaMint corpora containing transcriptions of the sessions of the 17 European national parliaments with half a billion words. The corpora are uniformly encoded, contain rich meta-data about 11 thousand speakers, and are linguistically annotated following the Universal Dependencies formalism and with named entities. Samples of the corpora and conversion scripts are available from the project's GitHub repository, and the complete corpora are openly available via the CLARIN.SI repository for download, as well as through the NoSketch Engine and KonText concordancers and the Parlameter interface for on-line exploration and analysis.

2.
Behav Res Methods ; 53(4): 1799-1816, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33904142

RESUMO

Psycholinguistic databases containing ratings of concreteness, imageability, age of acquisition, and subjective frequency are used in psycholinguistic and neurolinguistic studies which require words as stimuli. Linguistic characteristics (e.g. word length, corpus frequency) are frequently coded, but word class is seldom systematically treated, although there are indications of its significance for imageability and concreteness. This paper presents the Croatian Psycholinguistic Database (CPD; available at: https://doi.org/10.17234/megahr.2019.hpb ), containing 6000 Croatian nouns, verbs, adjectives and adverbs, rated for concreteness, imageability, age of acquisition, and subjective frequency. Moreover, we present computationally obtained extrapolations of concreteness and imageability to the remainder of the Croatian lexicon (available at: https://github.com/megahr/lexicon/blob/master/predictions/hr_c_i.predictions.txt ). In the two studies presented here, we explore the significance of word class for concreteness and imageability in human and computationally obtained ratings. The observed correlations in the CPD indicate correspondences between psycholinguistic measures expected from the literature. Word classes exhibit differences in subjective frequency, age of acquisition, concreteness and imageability, with significant differences between nouns, verbs, adjectives and adverbs. In the computational study which focused on concreteness and imageability, concreteness obtained higher correlations with human ratings than imageability, and the system underpredicted the concreteness of nouns, and overpredicted the concreteness of adjectives and adverbs. Overall, this suggests that word class contains schematic conceptual and distributional information. Schematic conceptual content seems to be more significant in human ratings of concreteness and less significant in computationally obtained ratings, where distributional information seems to play a more significant role. This suggests that word class differences should be theoretically explored.


Assuntos
Idioma , Psicolinguística , Humanos
3.
Front Artif Intell ; 6: 986890, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37275533

RESUMO

Introduction: We examine the profiles of hate speech authors in a multilingual dataset of Facebook reactions to news posts discussing topics related to migrants and the LGBT+ community. The included languages are English, Dutch, Slovenian, and Croatian. Methods: First, all utterances were manually annotated as hateful or acceptable speech. Next, we used binary logistic regression to inspect how the production of hateful comments is impacted by authors' profiles (i.e., their age, gender, and language). Results: Our results corroborate previous findings: in all four languages, men produce more hateful comments than women, and people produce more hate speech as they grow older. But our findings also add important nuance to previously attested tendencies: specific age and gender dynamics vary slightly in different languages or cultures, suggesting that distinct (e.g., socio-political) realities are at play. Discussion: Finally, we discuss why author demographics are important in the study of hate speech: the profiles of prototypical "haters" can be used for hate speech detection, for sensibilization on and for counter-initiatives to the spread of (online) hatred.

4.
PLoS One ; 17(3): e0265602, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35298556

RESUMO

We address a challenging problem of identifying main sources of hate speech on Twitter. On one hand, we carefully annotate a large set of tweets for hate speech, and deploy advanced deep learning to produce high quality hate speech classification models. On the other hand, we create retweet networks, detect communities and monitor their evolution through time. This combined approach is applied to three years of Slovenian Twitter data. We report a number of interesting results. Hate speech is dominated by offensive tweets, related to political and ideological issues. The share of unacceptable tweets is moderately increasing with time, from the initial 20% to 30% by the end of 2020. Unacceptable tweets are retweeted significantly more often than acceptable tweets. About 60% of unacceptable tweets are produced by a single right-wing community of only moderate size. Institutional Twitter accounts and media accounts post significantly less unacceptable tweets than individual accounts. In fact, the main sources of unacceptable tweets are anonymous accounts, and accounts that were suspended or closed during the years 2018-2020.


Assuntos
Meios de Comunicação , Mídias Sociais , Ódio , Humanos , Idioma , Fala
5.
Appl Netw Sci ; 6(1): 96, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957317

RESUMO

Twitter data exhibits several dimensions worth exploring: a network dimension in the form of links between the users, textual content of the tweets posted, and a temporal dimension as the time-stamped sequence of tweets and their retweets. In the paper, we combine analyses along all three dimensions: temporal evolution of retweet networks and communities, contents in terms of hate speech, and discussion topics. We apply the methods to a comprehensive set of all Slovenian tweets collected in the years 2018-2020. We find that politics and ideology are the prevailing topics despite the emergence of the Covid-19 pandemic. These two topics also attract the highest proportion of unacceptable tweets. Through time, the membership of retweet communities changes, but their topic distribution remains remarkably stable. Some retweet communities are strongly linked by external retweet influence and form super-communities. The super-community membership closely corresponds to the topic distribution: communities from the same super-community are very similar by the topic distribution, and communities from different super-communities are quite different in terms of discussion topics. However, we also find that even communities from the same super-community differ considerably in the proportion of unacceptable tweets they post.

6.
PLoS One ; 16(9): e0256175, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34469456

RESUMO

Communities in social networks often reflect close social ties between their members and their evolution through time. We propose an approach that tracks two aspects of community evolution in retweet networks: flow of the members in, out and between the communities, and their influence. We start with high resolution time windows, and then select several timepoints which exhibit large differences between the communities. For community detection, we propose a two-stage approach. In the first stage, we apply an enhanced Louvain algorithm, called Ensemble Louvain, to find stable communities. In the second stage, we form influence links between these communities, and identify linked super-communities. For the detected communities, we compute internal and external influence, and for individual users, the retweet h-index influence. We apply the proposed approach to three years of Twitter data of all Slovenian tweets. The analysis shows that the Slovenian tweetosphere is dominated by politics, that the left-leaning communities are larger, but that the right-leaning communities and users exhibit significantly higher impact. An interesting observation is that retweet networks change relatively gradually, despite such events as the emergence of the Covid-19 pandemic or the change of government.


Assuntos
COVID-19/epidemiologia , Redes Sociais Online , Pandemias , SARS-CoV-2 , Mídias Sociais , Humanos
7.
Folia Biol (Krakow) ; 57(1-2): 91-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19459466

RESUMO

For the first time effects of norflurazon on green (Hydra viridissima Pallas, 1766) and brown hydra (Hydra oligactis Pallas, 1766) in high- and low-light conditions were investigated in order to establish the extent of damage that this substance inflicts, with special emphasis on the "bleaching effect" and the effect on hydra-algae symbiosis. Green hydra is a typical example of an endosymbiotic organism. The gastrodermal myoepithelial cells of green hydra contain endosymbiotic algae. Norflurazon is a selective translocational herbicide that induces a "bleaching effect" on newly developed chloroplasts, resulting in a decrease of photosynthetic activity and viability of the organism. In the experiment, morphological (binocular), cytological and histological (Bouin fixative, dehydration, paraplast embedding, Hämalaun-eosine staining, light microscope) and conventional transmission electron microscopy (cTEM) (glutaraldehyde, dehydration, raisin, uranyl-acetate, Pb-citrate) were used. Depending on the concentration and light conditions, norflurazon caused mortality, deformations, changes in behavior, locomotion and asexual reproduction, changes in the structure of all 3 layers in hydras, changes in the position and shape of endosymbiotic algae inside the hydra body as well as ultrastructural changes of treated hydras and endosymbiotic algae. Under low concentrations of norflurazon the effects on hydra were similar to the controls, while in the highest concentrations especially manifested were antichloroplastal and antimitochondrial effects. Norflurazon caused a great extent of damage and induced deleterious effects also upon other cellular components such as cellular membranes, ER, Golgi apparatus, ribosomes. Newly developed buds in symbiotic green hydras were not bleached. After a recovery period, the green hydra individuals that had survived re-established regular endosymbiosis with algae and recovered completely, whereas brown hydras recovered only partially.


Assuntos
Herbicidas/farmacologia , Hydra/efeitos dos fármacos , Piridazinas/farmacologia , Animais , Hydra/fisiologia , Hydra/ultraestrutura , Simbiose/efeitos dos fármacos
8.
J Trace Elem Med Biol ; 46: 62-75, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29413112

RESUMO

Rodent kidneys exhibit three isoforms of metallothioneins (MTs), MT1, MT2 and MT3, with poorly characterized localization along the nephron. Here we studied in adult male Wistar rats the renal expression of MTs mRNA by end-point RT-PCR and MT proteins by immunochemical methods The expression pattern of MT1 mRNA was cortex (CO)>outer stripe (OS)=inner stripe (IS)=inner medulla (IM), of MT2 mRNA was IM>CO>IS=OS, and of MT3 mRNA was IM>CO=OS=IM. MT1/2-antibody stained with heterogeneous intensity the cell cytoplasm and nuclei in proximal tubule (PT) and thin ascending limb, whereas MT3-antibody stained weakly the cell cytoplasm in various cortical tubules and strongly the nuclei in all nephron segments. However, the isolated nuclei exhibited an absence of MT1/2 and presence of MT3 protein. In MT1/2-positive PT cells, the intracellular staining appeared diffuse or bipolar, but the isolated brush-border, basolateral and endosomal membranes were devoid of MT1/2 proteins. In the lumen of some PT profiles, the heterogeneously sized MT1/2-rich vesicles were observed, with the limiting membrane positive for NHE3, but negative for V-ATPase, CAIV, and megalin, whereas their interior was positive for CAII and negative for cytoskeleton. They seem to be pinched off from the luminal membrane of MT1/2-rich cells, as also indicated by transmission electron microscopy. We conclude that in male rats, MTs are heterogeneously abundant in the cell cytoplasm and/or nuclei along the nephron. The MT1/2-rich vesicles in the tubule lumen may represent a source of urine MT and membranous material, whereas MT3 in nuclei may handle zink and locally-produced reactive oxygen species.


Assuntos
Metalotioneína/metabolismo , Néfrons/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Imuno-Histoquímica , Masculino , Metalotioneína 3 , Microscopia Eletrônica de Transmissão , Ratos Wistar
9.
Folia Biol (Krakow) ; 55(1-2): 77-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17687938

RESUMO

New observations on green hydra symbiosis are described. Herbicide norflurazon was chosen as a "trigger" for analysis of these observations. Green hydra (Hydra viridissima Pallas, 1766) is a typical example of endosymbiosis. In its gastrodermal myoeptihelial cells it contains individuals of Chlorella vulgaris Beij. (KESSLER & HUSS 1992). Ultrastructural changes were observed by means of TEM. The newly described morphological features of green hydra symbiosis included a widening of the perialgal space, missing symbiosomes and joining of the existing perialgal spaces. Also, on the basis of the newly described mechanisms, the recovery of green hydra after a period of intoxication was explained. The final result of the disturbed symbiosis between hydra and algae was the reassembly of the endosymbiosis in surviving individuals.


Assuntos
Hydra/fisiologia , Animais , Chlorella vulgaris/fisiologia , Chlorella vulgaris/ultraestrutura , Croácia , Hydra/ultraestrutura , Simbiose/fisiologia
10.
Toxicol In Vitro ; 20(3): 286-94, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16182506

RESUMO

Two kinds of nanosize V(2)O(5) particles were synthesized in our own laboratory and concomitantly applied to V79 and L929 fibroblasts and SCCVII, B16F10 and FsaR tumor cells. The morphologies of the cells were monitored using an inverted inverse microscope equipped with digital camera, while quantitative determination of the cytotoxicity of nanosize V(2)O(5) particles was measured using crystal violet bioassay. Twenty four hours after the addition of nanosize V(2)O(5) particles (20muM), noticeable changes in the morphology and density of fibroblast and cancer cells were observed. Reculturing in a freshly prepared medium for the next 24h showed a high recovery effect on V79, SCCVII and B16F10 cells, while FsaR and L929 cells were seriously damaged and unable to recover. At a higher concentration of nanosize V(2)O(5) particles (100muM), the cytotoxicity of V(2)O(5) prevailed against the recovery effect in all cell types. Quantitative measurements have shown that the resistance of investigated cell cultures to the cytotoxicity of nanosize V(2)O(5) particles decreases in the order V79>SCCVII>B16F10>FsaR>L929. The high cytotoxic effect found on FsaR cells suggests that nanosize V(2)O(5) particles could be regarded as poisoning material in the treatment of FsaR fibrosarcoma cells. Possible mechanisms involved in the cytotoxicity of nanosize V(2)O(5) particles were discussed.


Assuntos
Fibroblastos/efeitos dos fármacos , Compostos de Vanádio/toxicidade , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Violeta Genciana , Glucose/farmacologia , Humanos , Microscopia Eletrônica de Transmissão , Nanoestruturas , Espectrofotometria Ultravioleta , Compostos de Vanádio/síntese química
11.
Acta Histochem ; 113(1): 49-52, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19740530

RESUMO

Body stiffness is important during undulatory locomotion in fish. In amphioxus, the myosepta play an important role in transmission of muscular forces to the notochord. In order to define the specific supporting role of the notochord in amphioxus during locomotion, the ultrastructure of 10 adult amphioxus specimens was analyzed using transmission electron microscopy. Numerous cilia-like structures were found on the surface of each notochordal cell at the sites of their attachment to the notochordal sheath. Ultrastructurally, these structures consisted of the characteristic arrangement of peripheral and central microtubular doublets and were anchored to the inner layer of the notochordal sheath. Immunohistochemically, a positive reaction to applied dynein and ß-tubulin antibodies characterized the area of the cilia-like structures. We propose that reduced back-and-forth movements of the cilia-like structures might contribute to the flow of the fluid content inside the notochord, thus modulating the stiffness of the amphioxus body during its undulatory locomotion.


Assuntos
Cordados não Vertebrados , Cílios/ultraestrutura , Dineínas/análise , Locomoção , Notocorda , Tubulina (Proteína)/análise , Animais , Cordados não Vertebrados/anatomia & histologia , Cordados não Vertebrados/ultraestrutura , Imuno-Histoquímica , Locomoção/fisiologia , Microscopia Eletrônica de Transmissão , Microtúbulos/ultraestrutura , Notocorda/anatomia & histologia , Notocorda/ultraestrutura
12.
Biol Chem ; 386(8): 777-83, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16201873

RESUMO

We demonstrate that basic components of the plastid protein-import apparatus originally found in pea, Toc34, Toc159, and Tic110, are also conserved in evolutionarily younger gymnosperms. We show that multiple isoforms of the preprotein receptor Toc34 differentially accumulate in various stages of needle development, while the amounts of Toc159 drastically decrease during chloroplast morphogenesis. Spruce Toc34 and Toc159 receptors are able to recognise and interact with the angiosperm precursor of the Rubisco small subunit. Young proplastids found in closed buds contain a highly elevated number of protein translocation complexes equipped with only two types of outer envelope receptors, Toc159 and a 30-kDa Toc34-related protein. Photosystem II (PSII) can already be assembled in a fully functional complex at this very early stage of needle development, suggesting that no additional receptor isoforms are needed for translocation of all necessary PSII components. We conclude that the accumulation of evolutionarily conserved plastid preprotein translocation components is differentially regulated during spruce needle development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/metabolismo , Picea/metabolismo , Proteínas de Plantas/metabolismo , Plastídeos/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Peptídeos/metabolismo , Transporte Biológico Ativo , Peso Molecular , Complexo de Proteína do Fotossistema II/química , Complexo de Proteína do Fotossistema II/metabolismo , Picea/crescimento & desenvolvimento , Plastídeos/química , Especificidade por Substrato
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