Spatial patterns
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Revised edition viii, 494 s. : il., tab., grafy ; 24 cm
... Contents -- Contributors vii -- Acknowledgements ix -- 1 GIS and spatial analysis: introduction and overview ... ... Stewart Fotheringham -- PART I INTEGRATING GIS AND SPATIAL ANALYSIS: -- AN OVERVIEW OF THE ISSUES 11 ... ... -- 2 A review of statistical spatial analysis in geographical information systems 13 -- Trevor C. ... ... Haining -- 4 Spatial analysis and GIS 65 -- Morton E. ?’ ... ... pattern analysers relevant to GIS 83 -- Stan ? ...
[1st ed.] 281 s.
- Klíčová slova
- geografický informační systém,
- Konspekt
- Lékařské vědy. Lékařství
- NLK Obory
- environmentální vědy
- lékařská informatika
OBJECTIVE: Growing interest in the examination of large-scale brain network functional connectivity dynamics is accompanied by an effort to find the electrophysiological correlates. The commonly used constraints applied to spatial and spectral domains during electroencephalogram (EEG) data analysis may leave part of the neural activity unrecognized. We propose an approach that blindly reveals multimodal EEG spectral patterns that are related to the dynamics of the BOLD functional network connectivity. APPROACH: The blind decomposition of EEG spectrogram by parallel factor analysis has been shown to be a useful technique for uncovering patterns of neural activity. The simultaneously acquired BOLD fMRI data were decomposed by independent component analysis. Dynamic functional connectivity was computed on the component's time series using a sliding window correlation, and between-network connectivity states were then defined based on the values of the correlation coefficients. ANOVA tests were performed to assess the relationships between the dynamics of between-network connectivity states and the fluctuations of EEG spectral patterns. MAIN RESULTS: We found three patterns related to the dynamics of between-network connectivity states. The first pattern has dominant peaks in the alpha, beta, and gamma bands and is related to the dynamics between the auditory, sensorimotor, and attentional networks. The second pattern, with dominant peaks in the theta and low alpha bands, is related to the visual and default mode network. The third pattern, also with peaks in the theta and low alpha bands, is related to the auditory and frontal network. SIGNIFICANCE: Our previous findings revealed a relationship between EEG spectral pattern fluctuations and the hemodynamics of large-scale brain networks. In this study, we suggest that the relationship also exists at the level of functional connectivity dynamics among large-scale brain networks when no standard spatial and spectral constraints are applied on the EEG data.
- MeSH
- časové faktory MeSH
- dospělí MeSH
- elektroencefalografie metody MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mladý dospělý MeSH
- mozek diagnostické zobrazování fyziologie MeSH
- nervová síť diagnostické zobrazování fyziologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
The study examines spatial patterns of effects of high temperature extremes on cardiovascular mortality in the Czech Republic at a district level during 1994-2009. Daily baseline mortality for each district was determined using a single location-stratified generalized additive model. Mean relative deviations of mortality from the baseline were calculated on days exceeding the 90th percentile of mean daily temperature in summer, and they were correlated with selected demographic, socioeconomic, and physical-environmental variables for the districts. Groups of districts with similar characteristics were identified according to socioeconomic status and urbanization level in order to provide a more general picture than possible on the district level. We evaluated lagged patterns of excess mortality after hot spell occurrences in: (i) urban areas vs. predominantly rural areas; and (ii) regions with different overall socioeconomic level. Our findings suggest that climatic conditions, altitude, and urbanization generally affect the spatial distribution of districts with the highest excess cardiovascular mortality, while socioeconomic status did not show a significant effect in the analysis across the Czech Republic as a whole. Only within deprived populations, socioeconomic status played a relevant role as well. After taking into account lagged effects of temperature on excess mortality, we found that the effect of hot spells was significant in highly urbanized regions, while most excess deaths in rural districts may be attributed to harvesting effects.
- MeSH
- demografie MeSH
- dospělí MeSH
- kardiovaskulární nemoci epidemiologie mortalita MeSH
- lidé středního věku MeSH
- lidé MeSH
- městské obyvatelstvo statistika a číselné údaje MeSH
- poruchy vyvolané tepelným stresem epidemiologie mortalita MeSH
- roční období MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- socioekonomické faktory MeSH
- venkovské obyvatelstvo statistika a číselné údaje MeSH
- vysoká teplota škodlivé účinky MeSH
- zeměpis MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika epidemiologie MeSH
Cíl Cílem předkládané práce je zjistit, jakým způsobem je postižena prostorová paměť u pacientů s Alzheimerovou chorobou a zda je postižena i u pacientů s Mírnou kognitivní poruchou. Je zde srovnáván kvalitativní charakter tohoto postiže¬ ní. Soubor a metodika. Vyšetřili jsme prostorovou paměť u 15 dobrovolníků a 42 pacientů, kteří byh vyšetřeni standardním protokolem a rozděleni podle klinických kritérií a výsledku neuropsychologického vyšetření do čtyř skupin: Alzheimerova choroba (ACH), Subjektivní poruchy paměti (SPP), neamnestická Mírná kognitivní porucha (naMCI) a amnestická Mírná kognitivní porucha (aMCI). Prostorová kognice byla vyšetřena Testem skrytého cíle (HGT), který srovnává deficit prostorové paměti ve dvou rozdílných složkách - egocentrické a alocentrické. Reálná verze testu byla prováděna v experimentálním stanu Blue Velvet Arena (BVA) a virtuální verze, která je mapovou analogií reálné verze, byla prováděna na osobním počítači (PC). Výsledky. U pacientů s ACH jsme zjistili v reálné i virtuální verzi testu poruchu v egocentrické a alocentrické složce prostorové paměti (p<0,01). U pacientů s aMCI bylo v obou verzích testu přítomno kvalita¬ tivné stejné, jen kvantitativně méně vyjádřené postižení v egocentrické (p<0,01) a alocentrické (p<0,05) složce prostorové paměti. Pacienti s naMCI selhávali v přechodu z egocentrické na alocentrickou fázi ve virtuální verzi testu (p<0,05). Pacienti se SPP nebyli postiženi ani v jedné ze složek prostorové paměti. Závěry. Vyšetření prostorové kognice může být podkladem pro klasifikaci pacientů do skupin: ACH, aMCI, naMCI a SPP. Prokázali jsme, že v případě ACH a aMCI se jedná o kontinuum kvantitativně různě vyjádřeného deficitu stejné kvality.
Objective. The aim was to investigate the pattern of spatial memory impairment in patients with Alzheimer's disease, and to find whether or not the spatial memory is impaired in patients with Mild Cognitive Impairment. The qualitative and quantitative characters of impairment were compared. Subjects and Methods. Spatial memory was examined in 15 healthy volunteers and 42 patients, who had undergone a standard diagnostic procedure. These patients were subsequently classified according to clinical criteria and neuropsychological testing into four groups: Alzheimer's disease (AD), Subjective memory complaints (SMC), nonamnestic Mild Cognitive Impairment (naMCI) and amnestie Mild Cognitive Impairment (aMCI). The Hidden Goal Task test was used to examine spatial memory. This test compares two types of spatial memory - egocentric and allocentric. A real version of the test was performed in an experimental tent Blue Velvet Arena (BVA), while a virtual version, which is the map analogy of the real version, was carried out on a personal computer (PC). Results. There was found an impairment in both egocentric and allocentric spatial memory (p<0.01) in patients with AD in the real as well as virtual versions of the test. Qualitatively similar, but quantitatively less profound impairment in egocentric (p<0.01) and allocentric (p<0.05) parts of spatial memory in both versions of the test was presented in patients with aMCI. Patients with naMCI were impaired in the transition from egocentric to allocentric virtual phase of the test (p<0.05). Subjects with SMC were not impaired in any part of spatial memory. Conclusions. The spatial memory examination can be used as the basis for patients' classification into the following groups: AD, aMCI, naMCI a SMC. Our experiments have proved that in the case of AD and aMCI it is a continuity of the same quality impairment but with quantitatively different expression.
BACKGROUND: Severe canopy-removing disturbances are native to many temperate forests and radically alter stand structure, but biotic legacies (surviving elements or patterns) can lend continuity to ecosystem function after such events. Poorly understood is the degree to which the structural complexity of an old-growth forest carries over to the next stand. We asked how pre-disturbance spatial pattern acts as a legacy to influence post-disturbance stand structure, and how this legacy influences the structural diversity within the early-seral stand. METHODS: Two stem-mapped one-hectare forest plots in the Czech Republic experienced a severe bark beetle outbreak, thus providing before-and-after data on spatial patterns in live and dead trees, crown projections, down logs, and herb cover. RESULTS: Post-disturbance stands were dominated by an advanced regeneration layer present before the disturbance. Both major species, Norway spruce (Picea abies) and rowan (Sorbus aucuparia), were strongly self-aggregated and also clustered to former canopy trees, pre-disturbance snags, stumps and logs, suggesting positive overstory to understory neighbourhood effects. Thus, although the disturbance dramatically reduced the stand's height profile with ~100% mortality of the canopy layer, the spatial structure of post-disturbance stands still closely reflected the pre-disturbance structure. The former upper tree layer influenced advanced regeneration through microsite and light limitation. Under formerly dense canopies, regeneration density was high but relatively homogeneous in height; while in former small gaps with greater herb cover, regeneration density was lower but with greater heterogeneity in heights. CONCLUSION: These findings suggest that pre-disturbance spatial patterns of forests can persist through severe canopy-removing disturbance, and determine the spatial structure of the succeeding stand. Such patterns constitute a subtle but key legacy effect, promoting structural complexity in early-seral forests as well as variable successional pathways and rates. This influence suggests a continuity in spatial ecosystem structure that may well persist through multiple forest generations.
Východiska: Glioblastom představuje nejčastější a zároveň nejagresivnější primární mozkový nádor dospělých. Radioterapii podstupuje naprostá většina pacientů s tímto onemocněním. Význam správného konturingu (stanovení cílových objemů) v radioterapii glioblastomů v současnosti stále stoupá. Dvěma základními přístupy ke konturování glioblastomů jsou postup "americký" dle Pracovní skupiny pro radioterapii v onkologii (Radiation Therapy Oncology Group – RTOG), tzv. RTOG contouring approach s definicí dvou cílových objemů, a postup "evropský" dle Evropské organizace pro výzkum a léčbu nádorových onemocnění (European Organisation for Research and Treatment of Cancer – EORTC), tzv. EORTC contouring approach s definicí jednoho cílového objemu. Oba přístupy v definování cílových objemů jsou považovány za standardní a v praxi se výběr konkrétního postupu liší i dle zvyklostí daného pracoviště. Významným parametrem hodnocení přístupu ke konturingu je prostorové hodnocení následných recidiv, tzv. patterns of failure (PoF). Cíl: Akademická klinická studie GlioART srovnává RTOG a EORTC přístupy v prospektivním nastavení a se zohledněním všech parametrů nutných pro validní hodnocení následných recidiv – definice recidiv, specifikace MR prokazujícího progresi, specifikace techniky plánované radioterapie, molekulárně biologické charakteristiky glioblastomů, rozsah resekce a lokalizace původního glioblastomu. Cílem tohoto textu je představit zmiňovanou studii GlioART a diskutovat přidružená témata spojená s definováním cílových objemů radioterapie. Závěr: Výsledky akademické studie GlioART mohou definovat doporučení ovlivňující každodenní praxi v radioterapii glioblastomů.
Background: Glioblastoma represents the most common and the most aggressive primary brain tumor in adults. Radiotherapy is indicated in almost all patients suffering with this disease. The importance of valid contouring (target volume definition) in radiotherapy of glioblastomas is currently increasing. The two basic contouring approaches in glioblastoma are the "American" approach of the Radiation Therapy Oncology Group (RTOG contouring approach defining two target volumes) and the "European" approach of the European Organization for Research and Treatment of Cancer (EORTC contouring approach with one target volume). Both mentioned approaches are considered standard of radiotherapy care. In daily radiotherapy practice, a specific contouring procedure is often chosen also according to the convention and tradition of the pertinent workplace. An important parameter in assessing the approach to contouring in radiotherapy is the evaluation of patterns of failure (PoF, spatial evaluation of subsequent relapses). Purpose: The GlioART, academic investigator initiated clinical study, compares the RTOG and EORTC approaches in a prospective setup, taking into account all parameters necessary for valid evaluation of progressions – definition of relapses, MR specification demonstrating progression, planned radiotherapy technique, glioblastoma molecular biological characteristics, resection extent and localization of the original glioblastoma. The aim of this paper is to present the GlioART study and to discuss the associated topics associated with defining the target volumes in radiotherapy.Conclusion: The results of the GlioART trial may define recommendations influencing daily clinical practice in glioblastoma radiotherapy.
