Spatial transformation
Dotaz
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- MeSH
- kognice MeSH
- lidé MeSH
- psychologické testy MeSH
- vyšší nervová činnost MeSH
- zraková percepce MeSH
- Check Tag
- lidé MeSH
V předchozích experimentech (Nekovarova et al., 2007) jsme ukázali, že makaci (Macaca mulatta) jsou schopni se orientovat v reálném prostoru na základě abstraktních vizuálních stimulů promítaných na obrazovku počítače. Vizuální stimuly byly dvojího druhu: „prostorové" („konfigurační"), které byly navrženy jako prostorová reprezentace reálného „odpověďového prostoru" a „neprostorové", které byly tvořeny jen jednoduchými obrazci bez implicitní prostorové informace. V prezentovaných experimentech jsme zkoumali schopnost makaků orientovat se podle prostorových stimulů, které jsme rotovali ve frontální rovině oproti reálnému „odpovědbvému prostoru" nebo u kterých jsme transformovali jejich geometrické vlastnosti. U prezentovaných stimulů jsme měnili velikost úhlů a poměr délky stran. Zkoumali jsme, jakou strategii používají makaci k reprezentaci těchto stimulů.
In previous experiments we demonstrated that macaque monkeys (Macaca mulatta) were able to orient in a real space according to abstract spatial stimuli presented on a computer screen. We used visual stimuli of both types: „spatial“ (designed as a representation of the real „response space“) and „non-spatial“ (simple patterns without any implicit spatial information). In present experiments we studied an ability of macaque monkeys to orient in the real space according to the spatial stimuli rotated in frontal plane against the real space or according to stimuli with transformed geometric features. We changed the geometric features of stimuli: angles and the lengths of walls. We studied which strategy the monkeys used to represent such abstract spatial stimuli.
Biological systems are hierarchically self-organized complex structures characterized by nonlinear interactions. Biochemical energy is transformed into work of physical forces required for various biological functions. We postulate that energy transduction depends on endogenous electrodynamic fields generated by microtubules. Microtubules and mitochondria colocalize in cells with microtubules providing tracks for mitochondrial movement. Besides energy transformation, mitochondria form a spatially distributed proton charge layer and a resultant strong static electric field, which causes water ordering in the surrounding cytosol. These effects create conditions for generation of coherent electrodynamic field. The metabolic energy transduction pathways are strongly affected in cancers. Mitochondrial dysfunction in cancer cells (Warburg effect) or in fibroblasts associated with cancer cells (reverse Warburg effect) results in decreased or increased power of the generated electromagnetic field, respectively, and shifted and rebuilt frequency spectra. Disturbed electrodynamic interaction forces between cancer and healthy cells may favor local invasion and metastasis. A therapeutic strategy of targeting dysfunctional mitochondria for restoration of their physiological functions makes it possible to switch on the natural apoptotic pathway blocked in cancer transformed cells. Experience with dichloroacetate in cancer treatment and reestablishment of the healthy state may help in the development of novel effective drugs aimed at the mitochondrial function.
- MeSH
- biologické modely * MeSH
- elektromagnetická pole * MeSH
- lidé MeSH
- mitochondrie účinky záření MeSH
- nádorová transformace buněk účinky záření MeSH
- nádory patofyziologie MeSH
- přenos energie * MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Knowledge of the spatial distribution of lipids in the intraocular lens is important for understanding the physiology and biochemistry of this unique tissue and for gaining a better insight into the mechanisms underlying diseases of the lens. Following our previous study showing the spatial distribution of sphingolipids in the porcine lens, the current study used ultra performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOFMS) to provide the whole lipidome of porcine lens and these studies were supplemented by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI MSI) of the lens using ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) to determine the spatial distribution of glycerophospholipids. Altogether 172 lipid species were identified with high confidence and their concentration was determined. Sphingomyelins, phosphatidylcholines, and phosphatidylethanolamines were the most abundant lipid classes. We then determined the spatial and concentration-dependent distributions of 20 phosphatidylcholines, 6 phosphatidylethanolamines, and 4 phosphatidic acids. Based on the planar molecular images of the lipids, we report the organization of fiber cell membranes within the ocular lens and suggest roles for these lipids in normal and diseased lenses.
- MeSH
- buněčná membrána metabolismus MeSH
- fosfatidylcholiny metabolismus MeSH
- fosfatidylethanolaminy metabolismus MeSH
- glycerofosfolipidy metabolismus MeSH
- ionty MeSH
- lipidy chemie MeSH
- oči metabolismus MeSH
- oční čočka metabolismus MeSH
- prasata MeSH
- sfingolipidy chemie MeSH
- sfingomyeliny metabolismus MeSH
- spektrometrie hmotnostní - ionizace laserem za účasti matrice metody MeSH
- spektroskopie infračervená s Fourierovou transformací metody MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Wavelet transformation is one of the most frequent procedures for data denoising, smoothing, decomposition, features extraction, and further related tasks. In order to perform such tasks, we need to select appropriate wavelet settings, including particular wavelet, decomposition level and other parameters, which form the wavelet transformation outputs. Selection of such parameters is a challenging area due to absence of versatile recommendation tools for suitable wavelet settings. In this paper, we propose a versatile recommendation system for prediction of suitable wavelet selection for data smoothing. The proposed system is aimed to generate spatial response matrix for selected wavelets and the decomposition levels. Such response enables the mapping of selected evaluation parameters, determining the efficacy of wavelet settings. The proposed system also enables tracking the dynamical noise influence in the context of Wavelet efficacy by using volumetric response. We provide testing on computed tomography (CT) and magnetic resonance (MR) image data and EMG signals mostly of musculoskeletal system to objectivise system usability for clinical data processing. The experimental testing is done by using evaluation parameters such is MSE (Mean Squared Error), ED (Euclidean distance) and Corr (Correlation index). We also provide the statistical analysis of the results based on Mann-Whitney test, which points out on statistically significant differences for individual Wavelets for the data corrupted with Salt and Pepper and Gaussian noise.
This study presents monitoring data on the spatial and temporal occurrence of pesticide residues in arable soils of the Czech Republic and relates it to soil properties, pesticide usage and data on application provided by farmers. In total, 34 soils were sampled during 2014-2017, amounting to 136 samples which were analyzed for 60 pesticides and four transformation products. Conazole fungicides were frequently present in soils above the limit of quantification and/or above the 0.01 mg/kg threshold. Of the other pesticide types, the herbicides diflufenican, chlorotoluron, metolachlor, pendimethalin and terbuthylazine, fungicides azoxystrobin, carbendazim, fenpropidin, fenpropimorph and prochloraz and the insecticide methoxyfenozide were found in ≥20% of soils in at least one sampling campaign. Soils typically (>50%) contained 2-7 residues with a maximum of 14. For the 136 samples, 116 different mixtures were identified. The occurrence of pesticides was driven by their annual usage, their half-lives in soil, and their hydrophobicity. A comparison of the monitoring data and pesticide application data provided by farmers revealed that 63% of the applied pesticides are not likely to persist until the following growing season while up to 69% of pesticide residues found in soils could be inherited from the previous growing season(s).
- MeSH
- aniliny MeSH
- herbicidy analýza MeSH
- insekticidy analýza MeSH
- látky znečišťující půdu analýza MeSH
- monitorování životního prostředí * MeSH
- pesticidy analýza MeSH
- průmyslové fungicidy analýza MeSH
- půda chemie MeSH
- rezidua pesticidů analýza MeSH
- triaziny MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
We studied the ability of monkeys and humans to orient in one spatial frame ("response frame") according to abstract spatial stimuli presented in another spatial frame ("stimulus frame"). The stimuli were designed as simple maps of the "response space". We studied how the transformations of these stimuli affected the performance. The subjects were trained to choose a particular position in the response frame - either on a touch screen (monkeys) or on a keyboard (humans) - according to schematic spatial stimuli presented on the stimulus screen. The monkeys responded by touching one of four circles shown in corners of a rectangle displayed on the touch screen. The correct position was signaled by the stimulus ("map") presented on the stimulus screen. The map was a complementary rectangle, but only with one circle shown ("pointer"). The position of this circle indicated the correct position in the response frame. In the first experiment we only manipulated stimuli presented on the computer screen. The "map" was originally shown in the same position and orientation as the "response pattern" but later the position and the rotation of the map on the screen were changing. Such transformations of the stimuli allow us to study the mental operations that the animals performed and how particular mental transformations mutually differed. In the second experiment we tested whether the monkeys relied more on stimuli presented on the screen or on the surrounding stable environment and objects. We compared the performance of animals in tasks with rotated virtual maps in a stable surrounding environment with the performance in tasks where we rotated the surrounding frame (computer monitor), whereas the stimuli on the screen remained stable. In the third experiment we tested human subjects in analogous tests to compare the ability and cognitive strategies of monkeys and humans in this task. We showed that the mental strategies that monkeys used for orientation in one spatial frame according to the map presented in the other spatial frame depended on the type of stimulus manipulation. We demonstrated that for monkeys there was a difference between solving "mental rotation" and "mental translocation" in this experimental design. We showed that humans were able both to mentally rotate and translocate the displayed stimuli. However, the mental rotation was more difficult than mental translocation also for them. These experiments help us to understand how the monkeys perceive the abstract spatial information, create the representation of space and how they transform the information about the position obtained from one spatial frame into another. The comparison between humans and monkeys allows us to study this cognitive ability in phylogeny.
- MeSH
- dospělí MeSH
- kognice fyziologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- Macaca mulatta MeSH
- mladý dospělý MeSH
- reakční čas MeSH
- rotace MeSH
- rozpoznávání obrazu * MeSH
- vnímání prostoru fyziologie MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Objective: The last 50 years in Poland has been a period of radical economic and demographic transformations. The deep economic crisis in 1980-1994 particularly affected people living in rural areas, especially in Pomerania, where for several years the net income of rural households fell by more than 40% year-on-year. This research aimed at analysing the prevalence of abnormal weight and the impact of various socioeconomic factors on the children’s development. Methods: This paper presents the results of 3,262 children aged 7-9 years from two rural schools in Central Pomerania examined in years 1978-2005. Measurement of body weight and height were used to calculate each child's BMI, then according to the criteria of the International Obesity Task Force, were allocated to one of four weight status categories: underweight, normal BMI, overweight and obesity. The intergroup differences in unrelated qualitative variables were estimated using the χ2 test with the analysis of the odds ratio, and the effect of the socioeconomic factors on the prevalence of abnormal children’s weight status was analysed with the Mantel-Haenszel test. Results: The study revealed that the number of children with abnormal weight status is increasing over time. The greatest rise of overweight and obese children was found between 1998 and 2005 (from 2.58% to 8.4%, p=0.002 among boys, and from 11.9% to 19.27%, p<0.0001 among girls). Simultaneously with the increasing of overweight and obese there was also an increase in the number of underweight children (from 6.64% to 14.8%, p=0.0003 among boys and from 9.46% to 16.08%, p=0.005, among girls). This trend has only recently been stopped. Conclusion: To control and ultimately stop the continuing problems related to abnormal body weight, effective and well-coordinated measures have to be taken. The managed actions must combat both underweight and overweight at the same time at every possible level and by different professionals.
PURPOSE: The aim of this work was to introduce a new algorithm for image reconstruction in bone SPECT and to compare its performances with a commercially available standard OSEM and resolution recovery (RR) reconstruction. MATERIALS AND METHODS: The algorithm was built applying the Lucy-Richardson deconvolution adn logarithmic image processing to the projections. A modification of the coefficients of wavelet decomposition was used to suppress the noise. The comparison with vendor software was performed both in a phantom study, using Signal-to-Noise ratio (SNR), Signal-to-Background ratio (SBR), spatial resolution and in clinical studies, by visual assessment of changes in contrast, spatial resolution and lesion detectability. RESULTS: A change in the SNR (from -4 to 40%), an increase in the SBR (from 19 to 40%), a minor improvement in spatial resolution and a similar noise level were observed in the phantom study in comparison to the standard OSEM. A decrease in the SNR, a worse spatial resolution, but only a 3 to 13 % lower SBR were achieved in comparison with the vendor supplied RR algorithm. The proposed algorithm creates patient images with better contrast and lesion detectability compared to clinically used OSEM. Compared to RR, more than half of obtained images showed better contrast and nearly half of them have better lesion detectability. CONCLUSION: The proposed algorithm compares favorably with the standard OSEM. Although less favorable, the comparison with RR and noise suppression algorithms, suggests that it can be used with only a slight decrease in the SBR.
- MeSH
- algoritmy * MeSH
- fantomy radiodiagnostické * MeSH
- jednofotonová emisní výpočetní tomografie přístrojové vybavení MeSH
- kosti a kostní tkáň MeSH
- lidé MeSH
- počítačové zpracování obrazu metody MeSH
- poměr signál - šum MeSH
- vlnková analýza * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH