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1.
Entropy (Basel) ; 25(2)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36832668

RESUMO

Based on Shannon's communication theory, in the present paper, we provide the theoretical background to finding an objective measurement-the text-entropy-that can describe the quality of digital natural language documents handled with word processors. The text-entropy can be calculated from the formatting, correction, and modification entropy, and based on these values, we are able to tell how correct or how erroneous digital text-based documents are. To present how the theory can be applied to real-world texts, for the present study, three erroneous MS Word documents were selected. With these examples, we can demonstrate how to build their correcting, formatting, and modification algorithms, to calculate the time spent on modification and the entropy of the completed tasks, in both the original erroneous and the corrected documents. In general, it was found that using and modifying properly edited and formatted digital texts requires less or an equal number of knowledge-items. In information theory, it means that less data must be put on the communication channel than in the case of erroneous documents. The analysis also revealed that in the corrected documents not only the quantity of the data is less, but the quality of the data (knowledge pieces) is higher. As the consequence of these two findings, it is proven that the modification time of erroneous documents is severalfold of the correct ones, even in the case of minimal first level actions. It is also proven that to avoid the repetition of the time- and resource-consuming actions, we must correct the documents before their modification.

2.
Entropy (Basel) ; 24(10)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37420512

RESUMO

Word processing is one of the most popular digital activities. Despite its popularity, it is haunted by false assumptions, misconceptions, and ineffective and inefficient practices leading to erroneous digital text-based documents. The focus of the present paper is automated numbering and distinguishing between manual and automated numbering. In general, one bit of information on the GUI-the position of the cursor-is enough to tell whether a numbering is manual or automated. To decide how much information must be put on the channel-the teaching-learning process-in order to reach end-users, we designed and implemented a method that includes the analysis of teaching, learning, tutorial, and testing sources, the collection and analysis of Word documents shared on the internet or in closed groups, the testing of grade 7-10 students' knowledge in automated numbering, and calculating the entropy of automated numbering. The combination of the test results and the semantics of the automated numbering was used to measure the entropy of automated numbering. It was found that to transfer one bit of information on the GUI, at least three bits of information must be transferred during the teaching-learning process. Furthermore, it was revealed that the information connected to numbering is not the pure use of tools, but the semantics of this feature put into a real-world context.

3.
PeerJ ; 6: e4913, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29868294

RESUMO

The name Elatine campylosperma Seub. is generally treated as one of the synonyms of E. macropoda Guss. However, recent morphological, phylogenetic and karyological studies indicate that this judgement should be revised. In the present paper we typify the name E. campylosperma, review its taxonomic history and provide a thorough description, with compilation of previously published data and our new measurements from in vitro cultures. Based on our herbarium survey, we outline its Atlantic-Mediterranean distribution area (Spain, France, Italy, Greece, Turkey and Algeria). Habitat preferences are summarized from our field observations, water quality measurements and the label information of the herbarium specimens examined. Intact E. campylosperma seeds were found in faecal samples of the Eurasian Coot (Fulica atra L.) in southern Spain and two of them were germinated, suggesting that E. campylosperma has a capacity for long distance dispersal via endozoochory.

4.
Sci Total Environ ; 607-608: 1001-1008, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-28724218

RESUMO

Alterations in traditional land use practices have led to severe declines in the area of semi-natural grasslands, thereby seriously threatening plant and animal species dependent on these habitats. Small anthropogenic managed habitats, like roadsides can act as refuges and might play an important role in conserving these species. Colonization of roadside verges by endangered lizard orchids (Himantoglossum spp.) has long been known, but few studies have systematically explored the suitability of roadside habitats for these orchids and the impact of roads on them. In this paper we present results of targeted surveys of three lizard orchid taxa on roadsides from eight European countries. During these surveys we searched for lizard orchids inhabiting roadside verges and recorded their distance from road, aspects of the roadside environment, as well as vegetative and reproductive characteristics of individual plants. We found large numbers of lizard orchids on roadside verges. Distance from roads was not uniformly distributed: orchids occurred more closely to roads than expected by chance. This suggests that regular management of roadsides (e.g. mowing) might enhance colonization and survival of lizard orchids. On the other hand, we also found that close proximity to roads negatively affects reproductive success, suggesting that the immediate vicinity of roads might act as an ecological trap (i.e. favorable in terms of colonization and survival but unfavorable in terms of reproduction). Nonetheless, the fact that significant and viable populations are maintained at roadsides suggests that traditionally managed roadside verges may allow long-term persistence of lizard orchid populations and may serve as refuges in a landscape context.


Assuntos
Ecossistema , Orchidaceae/crescimento & desenvolvimento , Refúgio de Vida Selvagem , Ecologia , Europa (Continente)
5.
Ecol Evol ; 7(24): 11257-11264, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29299298

RESUMO

Harvest of orchid tubers for salep production is widespread in southwestern Asia and the Balkans and constitutes a major conservation risk for wild orchid populations. Synanthropic habitats, such as graveyards, are important refuges for orchids and other organisms and could offer protection from salep harvesting because of their special cultural role. However, little is known about the occurrence and factors influencing harvesting of salep in graveyards. During field surveys of 474 graveyards throughout Turkey, we observed 333 graveyards with orchids, 311 graveyards with tuberous orchids, and salep harvest in 14 graveyards. Altogether, 530 individuals of 17 orchid species were collected, representing 9% of the individuals recorded. Harvesting intensity was relatively low, and populations were usually not wholly destroyed. However, some species were clearly more affected than others. Salep harvesting risk of orchid species was significantly associated with flowering time, with early-flowering species being more affected. A marginally significant positive relationship between harvesting risk and species-specific tuber size was also detected. Our data suggest that graveyards might offer some protection against salep harvesting in Turkey, but they also show that some orchid taxa are much more affected than others. Overall, our observations add more weight to the conservation value of these special habitats.

7.
Chaos ; 25(6): 064608, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26117133

RESUMO

Occurrence of bi- and trirhythmicities (coexistence of two or three stable limit cycles, respectively, with distinctly different periods) has been studied experimentally by applying delayed feedback control to the copper-phosphoric acid electrochemical system oscillating close to a Hopf bifurcation point under potentiostatic condition. The oscillating electrode potential is delayed by τ and the difference between the present and delayed values is fed back to the circuit potential with a feedback gain K. The experiments were performed by determining the period of current oscillations T as a function of (both increasing and decreasing) τ at several fixed values of K. With small delay times, the period exhibits a sinusoidal type dependence on τ. However, with relatively large delays (typically τ ≫ T) for each feedback gain K, there exists a critical delay τcrit above which birhythmicity emerges. The experiments show that for weak feedback, Kτcrit is approximately constant. At very large delays, the dynamics becomes even more complex, and trirhythmicity could be observed. Results of numerical simulations based on a general kinetic model for metal electrodissolution were consistent with the experimental observations. The experimental and numerical results are also interpreted by using a phase model; the model parameters can be obtained from experimental data measured at small delay times. Analytical solutions to the phase model quantitatively predict the parameter regions for the appearance of birhythmicity in the experiments, and explain the almost constant value of Kτcrit for weak feedback.

8.
Magy Onkol ; 56(2): 79-83, 2012 May.
Artigo em Húngaro | MEDLINE | ID: mdl-22629544

RESUMO

The authors present the diverse etiology of nipple discharge, which background may be a tumor. They discuss the checkup ways of nipple discharge and review in detail the galactographic technique and evaluation. The examination of pathologic nipple discharge is essentially based on contact cytology, x-ray-, and ultrasound mammography. Consequently, galactography is applied by filling the ducts with contrast material. The final diagnosis is rendered by histologic examination, following the operation. The authors demonstrate the application and role of galactography through various cases.


Assuntos
Doenças Mamárias/diagnóstico , Exsudatos e Transudatos , Mamilos , Adulto , Idoso , Doenças Mamárias/diagnóstico por imagem , Doenças Mamárias/patologia , Doenças Mamárias/cirurgia , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Lobular/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Feminino , Doença da Mama Fibrocística/diagnóstico , Humanos , Mamografia , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Mamilos/patologia , Mamilos/fisiopatologia , Ultrassonografia Mamária
9.
Orv Hetil ; 153(1): 3-13, 2012 Jan 08.
Artigo em Húngaro | MEDLINE | ID: mdl-22204829

RESUMO

Early diagnosis and prevention have the most significant effect on overall disease specific outcome; 90% of all breast cancer cases could be cured if diagnosed early and treated accurately. As for all diagnostic methods the most important requirement for diagnostic imaging is to detect breast cancer in its early stage, and to determine accurate tumor staging, in order to select the appropriate therapy. Its role is to monitor the effectiveness of therapy, to follow up patients reliably for early detection of recurrent disease. The spectrum of radiological imaging methods in breast cancer became broader in the past two decades; imaging that provides functional or metabolic data and whole body information such as CT, MRI and PET-CT are now available besides common X-ray and ultrasound mammography. The MRI is getting more and more important for the detection and characterization of breast cancer. Multimodal imaging techniques provide more accurate analysis, which is confirmed by increasing statistics authentically, but none of the imaging methods was specific enough to provide histological diagnosis. However, imaging-guided biopsies enable precise histological or cytological confirmation.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/cirurgia , Mama/patologia , Detecção Precoce de Câncer , Mamografia , Ultrassonografia Mamária , Algoritmos , Biópsia/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama Masculina/diagnóstico , Neoplasias da Mama Masculina/cirurgia , Detecção Precoce de Câncer/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vigilância da População , Valor Preditivo dos Testes , Medição de Risco , Tomografia Computadorizada por Raios X
10.
J Phys Chem B ; 115(39): 11409-19, 2011 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-21848262

RESUMO

We report Monte Carlo simulation results for double layers of 1:1 and 2:1 electrolytes near an electrode with an inner layer that has a dielectric constant, ε(2), smaller than that of the electrolyte, ε(3). The electrolyte is modeled in the implicit solvent framework (primitive model), while the electrode is a metal electrode in this study (ε(1) → ∞). The charged hard sphere ions are not allowed to enter into the inner layer. We show that the capacitance of the inner layer is C(δ) = ε(0)(ε(2) + ε(3))/2δ, where δ is the thickness of the inner layer. This result is different from that obtained from solutions of the Poisson-Boltzmann equation (ε(0)ε(2)/δ), indicating that interpretation of experimental data with a fitted ε(2) dielectric constant of the inner layer must be done using a different equation. We also show that the properties of the diffuse layer are not independent of the value of ε(2), which is a usual assumption of the Poisson-Boltzmann theory. This is mainly because the repulsive image charges repel both the counterions and the co-ions, while the electrode charge attracts the counterions and repels the co-ions.

11.
Am J Cardiol ; 92(4): 489-92, 2003 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12914890

RESUMO

This study assesses the effect of a first cigarette smoked in the morning on the QT interval duration in healthy habitual smokers after not smoking overnight. This study demonstrates that although after cigarette smoking the QT(Bc) values increase, the QT(Fc) and QT(Lc) values remained unchanged, and an increased sympathetic response was evident. The discrepancies between the results seen by different QT correction formulas emphasize the importance of selecting an accurate method for heart rate correction when evaluating and interpreting alterations in QT values.


Assuntos
Eletrocardiografia , Fumar/fisiopatologia , Adulto , Pressão Sanguínea , Feminino , Frequência Cardíaca , Humanos , Masculino
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