spatial variability
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Quantifying intraspecific and interspecific trait variability is critical to our understanding of biogeography, ecology and conservation. But quantifying such variability and understanding the importance of intraspecific and interspecific variability remain challenging. This is especially true of large geographic scales as this is where the differences between intraspecific and interspecific variability are likely to be greatest. Our goal is to address this research gap using broad-scale citizen science data to quantify intraspecific variability and compare it with interspecific variability, using the example of bird responses to urbanization across the continental United States. Using more than 100 million observations, we quantified urban tolerance for 338 species within randomly sampled spatial regions and then calculated the standard deviation of each species' urban tolerance. We found that species' spatial variability in urban tolerance (i.e. standard deviation) was largely explained by the variability of urban cover throughout a species' range (R2 = 0.70). Variability in urban tolerance was greater in species that were more tolerant of urban cover (i.e. the average urban tolerance throughout their range), suggesting that generalist life histories are better suited to adapt to novel anthropogenic environments. Overall, species differences explained most of the variability in urban tolerance across spatial regions. Together, our results indicate that (1) intraspecific variability is largely predicted by local environmental variability in urban cover at a large spatial scale and (2) interspecific variability is greater than intraspecific variability, supporting the common use of mean values (i.e. collapsing observations across a species' range) when assessing species-environment relationships. Further studies, across different taxa, traits and species-environment relationships are needed to test the role of intraspecific variability, but nevertheless, we recommend that when possible, ecologists should avoid using discrete categories to classify species in how they respond to the environment.
Brucellosis in cattle and humans has received world-wide research attention as a neglected and re-emerging zoonotic disease with many routes of transmission. Studies of brucellosis in Uganda have emphasized occupational exposures and also revealed variations in prevalence levels by region and cattle production systems. To date, research linking pastoralist household income from dairy production to brucellosis and its transmission risk pathways do not exist in Uganda. We assessed whether spatial differences in unit milk prices can be explained by brucellosis prevalence in cattle along a distance gradient from Lake Mburo National Park in Uganda. Semi-structured interviews administered to 366 randomly selected household heads were supplemented with serological data on brucellosis in cattle. Statistical analysis included Pearson correlation test, multiple regression and analysis of variance (ANOVA) using SPSS version 17. Serological results showed that 44% of cattle blood samples were sero-positive for brucellosis. The results obtained from interviews put the statistical mean of household reported cattle abortions at 5.39 (5.08-5.70 at 95% CI, n=366). Post-hoc analysis of variance revealed that both sero-positive cattle and reported cattle abortions significantly were much lower when moving outwards from the park boundary (p<0.05), while the price of milk increased significantly (p<0.05) along the same distance gradient. Further studies should identify public and private partnerships needed to create and strengthen good zoonotic brucellosis management practices at the nexus of wildlife and livestock in Uganda.
- MeSH
- brucelóza epidemiologie veterinární MeSH
- dobytek MeSH
- lidé MeSH
- mlékárenství * MeSH
- mléko ekonomika MeSH
- nemoci skotu epidemiologie MeSH
- prevalence MeSH
- prostorová analýza MeSH
- riziko MeSH
- skot MeSH
- těhotenství MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- skot MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Uganda epidemiologie MeSH
Indoor dust is often used to evaluate levels of organic compounds indoors, particularly for compounds with indoor sources, such as flame retardants (FRs). Yet there are uncertainties about the type of information that can be obtained from indoor dust. This study reports detailed dust sampling to assess spatial variability in indoor dust concentrations, the relationship between FR sources and dust, and the implications when interpreting dust concentrations. Multiple dust samples were collected from a range of surface types in three large rooms: a residential flat, a university seminar room, and a university computer room. Samples were analysed for polybrominated diphenyl ethers (PBDEs), novel halogenated flame retardants (NFRs) and organophosphate esters (OPEs). FR levels in dust varied significantly between and within rooms. Levels typically ranged over one order of magnitude within a room, and up to four orders of magnitude for a few OPEs. The spatial distribution of FRs related (in some cases) to proximity to sources, surface properties, and dust surface loadings. Differences also existed between surface and floor dusts, e.g., the contribution of TBOEP to ∑OPEs was higher in floor than surface dust, which has implications for human exposure assessment; adults typically have more contact with elevated surfaces, while young children have greater contact with floor surfaces. Overall, significant spatial heterogeneity exists in indoor dust, even in seemingly homogeneous indoor spaces, thus hampering comparability between studies and locations when single samples are collected. Composite samples are strongly recommended to limit the influence of spatial heterogeneity.
- MeSH
- lidé MeSH
- monitorování životního prostředí metody MeSH
- prach analýza MeSH
- retardanty hoření terapeutické užití MeSH
- znečištění vzduchu ve vnitřním prostředí analýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Tradičně se lidská ruka studuje prostřednictvím měření a srovnávání jednotlivých segmentů (prstů, článků prstů, záprstních kostí) bez zohlednění jejich vzájemných prostorových souvislostí. Cílem této studie je výzkum vnitro-populační variability formy lidské ruky jako celku v oblasti tříčlánkových prstů se zvláštním zaměřením na sexuální dimorfismus a vztah mezi velikostí a tvarem ruky. Pravé ruce 99 žen a 70 mužů, převážně vysokoškolských studentů, byly ve standardizované poloze z palmární strany zaznamenány běžným stolním skenerem. Na každém dvourozměrném snímku bylo umístěno 16 význačných bodů a byla studována variabilita mezi těmito konfiguracemi prostřednictvím metod geometrické morfometrie. Pro lepší pochopení vnitřních vzorců variability tvaru byl tvarový prostor rozložen na afinní a neafinní podprostor, které byly dále analyzovány samostatně. Převážná část celkové variability byla spojena s afinními tvarovými rozdíly, které jsou identické v celé studované oblasti ruky. Jejich větší část představovala střižnou změnu v proximodistálním směru, menší část pak napínání odpovídající změnám v šířce ruky. Toto napínání také silně korelovalo s velikostí ruky. Mezipohlavní rozdíly představovala afinní změna, ve které byla proximodistální střižná změna neoddělitelně spojena se změnami v relativní šířce ruky. Lokální neafinní pohlavní rozdíly byly zaznamenány v určitých článcích prstů a mohou souviset s rozdíly v poměrech délek prstů. Domníváme se, že oddělení globálních a lokálních sexuálně dimorfních znaků ruky může pomoci blíže ozřejmit původ/počátek jejich dimorfismu v rané ontogenezi – čím lokálnější znak, tím později se v ontogenezi zakládá. Dimorfní znaky lokální a globální by proto mohly být ovlivněny odlišnými ontogenetickými faktory.
Traditionally, the human hand has been analyzed by measuring and comparing individual segments (fingers, phalanges, metacarpals) without considering their mutual spatial relationships. The present study aimed to analyze intra-population variability of the human hand form in the region of fingers as whole with special focus given to sexual dimorphism and the association between shape and size. Right hands of 99 females and 70 males, mostly college students, were scanned with a document scanner in standardized position from the palmar side. For each image 2-D coordinates of 16 landmarks were recorded and variability between configurations of landmarks were studied using geometric morphometrics. To understand patterns of variability, shape spaces were decomposed into affine and non-affine subspaces and further studied separately. The prevalence of the total variability was associated with affine shape change identical for the whole studied region of the hand. Its major portion was represented by shearing in proximodistal direction and to a lesser extent by straining in the relative hand width. The strain also strongly correlated with size of the hand. Intersexual differences were represented by affine change in which the proximodistal shearing was inextricably tied with the differences in relative hand width. Local non-affine sex differences were found in specific phalanges and might be associated with differences in finger length ratios. We presume that separating global and local sexually dimorphic features of the hand might shed light on the origin/onset of the dimorphism during early ontogeny – the more local the feature, the later differentiated, and thus influenced by different ontogenetic factors than global features.
- Klíčová slova
- geometrická morfometrie,
- MeSH
- anatomická značka MeSH
- charakteristické znaky pohlaví * MeSH
- fenotyp MeSH
- lidé MeSH
- ruka * anatomie a histologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
Considering that most of the falls in elderly population arise during walking, tests derived from walking performance would be desirable for comprehensive fall risk assessment. The analysis of spatial temporal parameters and the center of pressure displacement, which represents the interaction between the human body and the ground, would be beneficial. The aim of this study was to compare spatial temporal gait parameters and their variability and the variability of the center of pressure displacement between elderly fallers and nonfallers during gait at self-selected, defined and fast speeds. A prospective study design was used. At the baseline, measurements of ground reaction force during gait at self-selected, defined and fast walking speeds by two force plates were performed. In addition, the Tinetti balance assessment tool, the Falls Efficacy Scale-International and the Activities-Specific Balance Confidence Scale were used. Mean and coefficient of variation of spatial temporal gait parameters and standard deviations of center of pressure displacement during loading response, midstance, terminal stance and preswing phases were calculated. Comparison of the fallers and nonfallers exhibited no significant difference in clinical tool, scales or spatial temporal parameters. Compared to nonfallers' increased variability of walking speed at self-selected and defined speed, step width at fast walking speed and center of pressure displacement during preswing phase in medial-lateral directions at defined walking speed was found in fallers. However, application of the Holm-Bonferroni procedure for multiple comparisons exhibited no significant effect of group in any of the gait parameters. In general, our study did not observe an effect of group (fallers vs. nonfallers) on variability of spatial temporal parameters and center of pressure movement during gait. However, walking speed, step width as well as standard deviation of COP displacement in the medial-lateral direction during preswing exhibited a certain potential for distinguishing between elderly fallers and nonfallers.
- MeSH
- biomechanika MeSH
- časoprostorová analýza MeSH
- chůze (způsob) fyziologie MeSH
- chůze fyziologie MeSH
- hodnocení rizik MeSH
- lidé středního věku MeSH
- lidé MeSH
- náhodné pády prevence a kontrola MeSH
- pohyb MeSH
- posturální rovnováha fyziologie MeSH
- prospektivní studie MeSH
- prostorové chování * MeSH
- senioři MeSH
- tělesná výška MeSH
- tlak MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Whereas temporal variability of plant phenology in response to climate change has already been well studied, the spatial variability of phenology is not well understood. Given that phenological shifts may affect biotic interactions, there is a need to investigate how the variability in environmental factors relates to the spatial variability in herbaceous species' phenology by at the same time considering their functional traits to predict their general and species-specific responses to future climate change. In this project, we analysed phenology records of 148 herbaceous species, which were observed for a single year by the PhenObs network in 15 botanical gardens. For each species, we characterised the spatial variability in six different phenological stages across gardens. We used boosted regression trees to link these variabilities in phenology to the variability in environmental parameters (temperature, latitude and local habitat conditions) as well as species traits (seed mass, vegetative height, specific leaf area and temporal niche) hypothesised to be related to phenology variability. We found that spatial variability in the phenology of herbaceous species was mainly driven by the variability in temperature but also photoperiod was an important driving factor for some phenological stages. In addition, we found that early-flowering and less competitive species characterised by small specific leaf area and vegetative height were more variable in their phenology. Our findings contribute to the field of phenology by showing that besides temperature, photoperiod and functional traits are important to be included when spatial variability of herbaceous species is investigated.
- MeSH
- fenotyp MeSH
- fotoperioda * MeSH
- klimatické změny MeSH
- listy rostlin * fyziologie MeSH
- roční období MeSH
- rostliny MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
Cíl. Práce zjišťuje korelace některých nových metod měření prostorové paměti k standardním neuropsychologickým metodám. Metody. V laboratoři vybudované na neurologickém oddělení Nemocnice Na Homolce v Praze byla použita modifikace zvířecích testů prostorové paměti pro testování lidí. Kromě toho byly vytvořeny počítačové analogie reálných navigačních testů, které by mohly být aplikovány při screeningu velkého počtu pacientů pro detekci časných příznaků paměťových poruch. Původních 32 proměnných prostorové paměti bylo převedeno na 7 proměnných. Ze standardních neuropsychologických metod byly použity WAIS-R, WMS-R, HRNB, WMS, Bentonova zkouška vizuální retence, Rey-Osterrietheova komplexní figura. Studie se účastnilo 54 osob, z toho 37 pacientů a 17 studentů. Z pacientů u části (n=20) se připravovala operace mozku pro farmakorezistentní epilepsii. šlo obvykle o hippokampektomie, a část (n=17) už dříve prodělala termolézi amygdalohippokampálního komplexu. Studenti byli bez neurologických nebo psychiatrických poruch v anamnéze. Výsledky. Byla zjištěna řada statisticky významných korelací. Například u proměnné prostorové paměti Skrytý cíl 1-4 je korelace chyb s neverbální inteligencí -0,636, p<0,001, s verbální inteligencí -0,403, p<0,05 při n=34. Celkové neuropsychologické oslabení (General Neuropsychological Deficit Scale, HRNB) má vazbu k počtu chyb v proměnné prostorové paměti Percepce 2 a 6 (r=0,800, p<0,01, n=15). Pozdější začátek epileptického onemocnění je spojený s menším výskytem chyb prostorové paměti (r=-0,360, p<0,05, n=29. proměnná Skrytý cíl 1-4). Závěr. Nově vytvořené testy prostorové paměti, vycházející z modifikace testů prostorové paměti u zvířat, i od nich odvozené počítačové analogie reálných navigačních testů, mají u lidí vazby také k inteligenci, paměti, neuropsychologickému oslabení, vzdělání, věku a začátku epileptického onemocnění.
Goal: This study investigates the correlations of some novel methods of measuring spatial memory to standard neuropsychological methods. Methods: In a laboratory established in the department of Neurology, Hospital Na Homolce in Prague, modification of animal tests of spatial memory was used for testing humans. Additionally, computer analogies of real navigation tests were made, which could be applied for screening a large number of patients for detection of early symptoms of memory disorders. The original 32 variables of spatial memory were converted to 7 variables. Among standard neuropsychology tests, the WAIS-R, WMS-R, HRNB, WMS, Benton test of visual retention and Rey-Osterrieth complex figure were used. Fifty-four patients participated in the study, including 37 patients and 17 students. Among the patients, one subgroup (n=20) was scheduled for brain surgery for pharmacoresistant epilepsy, usually hippocampectomy, another subgroup (n=17) had already undergone a thermolesion of the amygdala-hippocampus complex. The students were without history of neurological or psychiatric disorders. Results: A number of statistically significant correlations were detected. For example, in a spatial memory variable Hidden Goal 1-4, the correlation of errors with nonverbal intelligence is -0.636, p< 0.001,with verbal intelligence -0.403, p<0.05 at n=34. The General Neuropsychological Deficit Scale, HRNB, is related to the number of errors in the spatial memory variable Perception 2 and 6 (r = 0.800, p<0.01, n=:15). Late beginning of epileptic disease is associated with smaller occurrence of spatial memory errors (r = -0.360, p<0.05, n=29, variable Hidden Goal 1-4). Conclusion: The newly created tests of spatial memory, based upon modified tests of spatial navigation in animals, as well as the derived computer analogies of real navigation tests are in humans also related to intelligence, memory, neuropsychological deficit, education, age and the beginning of epileptic disease.
- MeSH
- dospělí MeSH
- epilepsie diagnóza MeSH
- finanční podpora výzkumu jako téma MeSH
- hipokampus chirurgie MeSH
- lidé MeSH
- neuropsychologické testy statistika a číselné údaje MeSH
- paměť MeSH
- poruchy paměti diagnóza MeSH
- studenti psychologie statistika a číselné údaje MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
The interaction of arthropods with the environment and the management of their populations is a focus of the ecological agenda. Spatial autocorrelation and under-sampling may generate bias and, when they are ignored, it is hard to determine if results can in any way be trusted. Arthropod communities were studied during two seasons and using two methods: window and panel traps, in an area of ancient temperate lowland woodland of Zebracka (Czech Republic). The composition of arthropod communities was studied focusing on four site level variables (canopy openness, diameter in the breast height and height of tree, and water distance) and finally analysed using two approaches: with and without effects of spatial autocorrelation. I found that the proportion of variance explained by space cannot be ignored (≈20% in both years). Potential bias in analyses of the response of arthropods to site level variables without including spatial co-variables is well illustrated by redundancy analyses. Inclusion of space led to more accurate results, as water distance and tree diameter were significant, showing approximately the same ratio of explained variance and direction in both seasons. Results without spatial co-variables were much more disordered and were difficult to explain. This study showed that neglecting the effects of spatial autocorrelation could lead to wrong conclusions in site level studies and, furthermore, that inclusion of space may lead to more accurate and unambiguous outcomes. Rarefactions showed that lower sampling intensity, when appropriately designed, can produce sufficient results without exploitation of the environment.
- MeSH
- členovci fyziologie MeSH
- ekosystém MeSH
- lidé MeSH
- mokřady MeSH
- odběr biologického vzorku MeSH
- populační dynamika MeSH
- prostorová analýza * MeSH
- roční období MeSH
- statistické modely * MeSH
- stromy fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
Even though cognitive testing in animals is widespread, many issues remain open - for example the influence of behavioural parameters on cognitive performance, stability of cognitive performance upon repeated testing, or comparability of cognitive variables across different tasks (i.e. cross-contextual consistency). In this study we tested thirty six male Long Evans laboratory rats and assessed their cognitive performance in two standard tasks of spatial navigation - Active allothetic place avoidance and Morris water maze test. Using multivariate analyses, we detected different aspects of cognition within these complex tasks (the ability to learn fast, cognitive flexibility, general ability to solve a task successfully). We found that consistency of cognitive performance in these two tasks (estimates of cognitive repeatability) differed substantially, reflecting differences in the experimental procedures. Moreover, we inspected cognitive performance of the animals in more detail by creating a correlation matrix of factors derived from these procedures. Nevertheless, we found no correlation and therefore no indication of a general cognitive ability in spatial navigation using these two tasks. In addition, we found no link between personality and cognition when correlating cognitive performance of the animals with parameters from personality tests, which were derived from a previous study conducted on the same animals. These findings highlight a task-dependent nature of cognitive performance in these two tasks of spatial navigation and suggest that general cognitive ability in spatial navigation may not be reliably inferred from these two tasks, while also indicating no evident link between cognition and personality in this context.
- MeSH
- bludiště - učení fyziologie MeSH
- chování zvířat fyziologie MeSH
- kognice * fyziologie MeSH
- krysa rodu rattus MeSH
- osobnost fyziologie MeSH
- potkani Long-Evans MeSH
- prostorová navigace * fyziologie MeSH
- učení vyhýbat se fyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Application of passive samplers is demonstrated for assessment of temporal and spatial trends of dissolved polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and priority metals in the middle stretch of the Danube river. Free dissolved concentrations of PAHs, measured using SPMD samplers, ranged from 5 to 72 ng L(-1). Dissolved PCBs in water were very low and they ranged from 5 to 16 pg L(-1). Concentration of mercury, cadmium, lead and nickel, measured using DGT samplers, were relatively constant along the monitored Danube stretch and in the range <0.1, <1-20, 18-74, and 173-544 ng L(-1), respectively. Concentrations of PAHs decreased with increasing temperature, which reflects the seasonality in emissions to water. This has an implication for the design of future monitoring programs aimed at assessment of long term trends. For such analysis time series should be constructed of data from samples collected always in the same season of the year.
- MeSH
- chemické látky znečišťující vodu analýza MeSH
- hydrofobní a hydrofilní interakce MeSH
- kovy analýza MeSH
- monitorování životního prostředí metody MeSH
- polychlorované bifenyly analýza MeSH
- polycyklické aromatické uhlovodíky analýza MeSH
- řeky chemie MeSH
- roční období MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH