Kernel density estimation
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This paper proposes a procedure which evaluates clusters of traffic accident and organizes them according to their significance. The standard kernel density estimation was extended by statistical significance testing of the resulting clusters of the traffic accidents. This allowed us to identify the most important clusters within each section. They represent places where the kernel density function exceeds the significance level corresponding to the 95th percentile level, which is estimated using the Monte Carlo simulations. To show only the most important clusters within a set of sections, we introduced the cluster strength and cluster stability evaluation procedures. The method was applied in the Southern Moravia Region of the Czech Republic.
- MeSH
- dopravní nehody statistika a číselné údaje MeSH
- lidé MeSH
- metoda Monte Carlo MeSH
- shluková analýza MeSH
- životní prostředí * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
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.
The bacterial endosymbiont Wolbachia has been used to control insect pests owing to its ability to manipulate their life history and suppress infectious diseases. Therefore, knowledge on Wolbachia dynamics in natural populations is fundamental. The European cherry fruit fly, Rhagoletis cerasi, is infected with the Wolbachia strain wCer2, mainly present in southern and central European populations, and is currently spreading into wCer2-uninfected populations driven by high unidirectional cytoplasmic incompatibility. Here, we describe the distribution of wCer2 along two transition zones where the infection is spreading into wCer2-uninfected R. cerasi populations. Fine-scale sampling of 19 populations in the Czech Republic showed a smooth decrease of wCer2 frequency from south to north within a distance of less than 20 km. Sampling of 12 Hungarian populations, however, showed a sharp decline of wCer2 infection frequency within a few kilometres. We fitted a standard wave equation to our empirical data and estimated a Wolbachia wave speed of 1.9 km yr-1 in the Czech Republic and 1.0 km yr-1 in Hungary. Considering the univoltine life cycle and limited dispersal ability of R. cerasi, our study highlights a rapid Wolbachia spread in natural host populations.
- MeSH
- prostorová analýza * MeSH
- Tephritidae mikrobiologie MeSH
- Wolbachia fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
- Maďarsko MeSH
The structure of forests is an important stabilizing factor regarding ongoing global climate and land use change. Biodiverse mountain forests with natural structure are one of the ecosystems most endangered by these problems. We focused on the mountain forest islands of European beech (Fagus sylvatica) and their role in the natural distribution of organisms. The study area was situated in the oldest Czech national park, Krkonoše (385 km2), which is the highest mountain ridge in the country. We studied multi-taxa (lichens, beetles and hymenopterans) responses to three hierarchical spatial levels of the environment: the topography was described by the elevation gradient; the patch structure was described by canopy openness, dead wood amounts, and Norway spruce (Picea abies) cover; and the tree level was described by species of the sampled tree and its diameter. Lichens preferred higher elevations, while insect groups responded conversely. Furthermore, insect groups were mainly influenced by the inner patch structure of beech islands. Lichens may be jeopardized due to the predicted future increase in temperatures, since they would need to shift toward higher altitudes. Insects may be mainly threatened in the future by land use changes (i.e., forest management) - as indicated by an interconnection of canopy openness and the amount of dead wood.
- MeSH
- biodiverzita * MeSH
- brouci klasifikace MeSH
- Hymenoptera klasifikace MeSH
- lesy * MeSH
- lišejníky klasifikace MeSH
- prostorová analýza MeSH
- zachování přírodních zdrojů MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
During the reign of the first Ptolemaic kings in Egypt, mainly in the 3rd and 2nd centuries BCE, the Egyptian cults related to the divine couple of Isis and Sarapis (i.e. the Isiac cults) spread successfully from Egypt to ports and coastal cities of the ancient Mediterranean. The discussion on the topic of the factors involved in the process of the early spread of these cults outside Egypt is still open and, so far, the research in this area has been conducted mainly by using established historiographical methods. However, these methods are limited when dealing with the interplay among different variables involved in complex historical processes. This article aims to overcome these limits by using a quantitative spatial network analysis. The results of our previous published research, which focused on a quantitative evaluation of the impact of individual factors on the early spread of the Isiac cults across the ancient Aegean Islands, suggest that the process was promoted by military and commercial activities of the Ptolemaic dynasty, and that the Ptolemaic military operations were the most influential factor. Following these results, this article focuses on the early spread of the Isiac cults on the west coast of Hellenistic Asia Minor, i.e. the region which the Ptolemies attempted to control in the 3rd and 2nd centuries BCE. The statistically significant results presented in this article support the hypothesis that the Ptolemaic political engagement in Asia Minor had a positive impact on the early spread of the Isiac cults. The results also suggest that the activities of the Seleucid dynasty, a political rival of the Ptolemies, in the area of interest could have constituted an immunological factor limiting the spread of the Isiac cults further to the eastern parts of Asia Minor.
- MeSH
- archeologie MeSH
- dějiny starověku MeSH
- doprava MeSH
- lidé MeSH
- politika * MeSH
- prostorová analýza MeSH
- Check Tag
- dějiny starověku MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- historické články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Asie MeSH
- starověký Egypt MeSH
OBJECTIVES: A growing body of research has incorporated the Social Vulnerability Index (SVI) into an expanded understanding of the social determinants of health. Although each component of SVI and its association with individual-level mental health conditions have been well discussed, variation in mentally unhealthy days (MUDs) at a county level is still unexplored. To systematically examine the geographically varying relationships between SVI and MUDs across the US counties, our study adopted two different methods: 1) aspatial regression modeling (ordinary least square [OLS]); and 2) locally calibrated spatial regression (geographically weighted regression [GWR]). STUDY DESIGN: This study used a cross-sectional statistical design and geospatial data manipulation/analysis techniques. Analytical unit is each of the 3109 counties in the continental USA. METHODS: We tested the model performance of two different methods and suggest using both methods to reduce potential issues (e.g., Simpson's paradox) when researchers apply aspatial analysis to spatially coded data sets. We applied GWR after checking the spatial dependence of residuals and non-stationary issues in OLS. GWR split a single OLS equation into 3109 equations for each county. RESULTS: Among 15 SVI variables, a combination of eight variables showed the best model performance. Notably, unemployment, person with a disability, and single-parent households with children aged under 18 years especially impacted the variation of MUDs in OLS. GWR showed better model performance than OLS and specified each county's varying relationships between subcomponents of SVI and MUDs. For example, GWR specified that 69.3% (2157 of 3109) of counties showed positive relationships between single-parent households and MUDs across the USA. Higher positive relationships were concentrated in Michigan, Kansas, Texas, and Louisiana. CONCLUSIONS: Our findings could contribute to the literature regarding social determinants of community mental health by specifying spatially varying relationships between SVI and MUDs across US counties. Regarding policy implementation, in counties containing more social and physical minorities (e.g., single-parent households and disabled population), policymakers should attend to these groups of people and increase intervention programs to reduce potential or current mental health illness. The results of GWR could help policymakers determine the specific counties that need more support to reduce regional mental health disparities.
- MeSH
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- prostorová analýza MeSH
- prostorová regrese * MeSH
- průřezové studie MeSH
- sociální zranitelnost * MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Michigan MeSH
Je pojednán vývoj prostoru v laterálním úseku dolního oblouku. Byla provedena analýza prostoru distálně od prvního stálého moláru. Byl sledován lineární parametr Ar-Pg, úhlyANB a Goniový úhel. Dosoubonj byli zařazeni jedinci, u kterých byly k dispozici dva kefalometrické snímky, zhotovené v období před a po pubertálním růstovém spurtu. Cílem práce bylo vyhodnotit velikost změny měřených lineárních a úhlových parametrů po proběhlém pubertálním růstovém spurtu a zjistit, zda existuje závislost mezi měřenými parametry na dolní čelisti a prostorem distálně od prvního stálého moláru. Po proběhlém růstovém spurtu bylo zjištěno statisticky významné zmenšení Goniového úhlu a úhlu ANB. Byla prokázána korelace mezi velikostí změny Ar-Pg a prostorem distálně od prvního dolního moláru. Korelace mezi velikostí změny Goniového úhlu, úhlu ANB a prostorem distálně od prvního dolního moláru nebyla prokázána
The space development laterally in the lower arch was discussed. The space analysis was performed in the region distally from the first permanent molar The linear parameter Ar-Pg, angles ANB and Gonion were registered. The sample included patients with two cephalograms - one taken prior and the other after the growth spurt. The aim of our work was to assess the change of linear and angular parameters after the growth spurt, and try to find out the relation between the measured parameters in the mandible and the space distally from the first permanent molar. After the finished growth spurt we indicated statistically significant decrease of the Gonion and ANB angles. The correlation between the change Ar-Pg, and the space distally from the first lower molar was proved. The relatlon between the change of Gonion, ANB angles and the space distally from the first lower molar was not found.
- Klíčová slova
- distální stěsnání, erupce druhého moláru,
- MeSH
- dentice - fyziologické jevy MeSH
- dítě MeSH
- kefalometrie metody využití MeSH
- lidé MeSH
- moláry anatomie a histologie růst a vývoj MeSH
- prořezávání zubů fyziologie MeSH
- prostorová analýza MeSH
- zubní oblouk anatomie a histologie růst a vývoj MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
Performing day surgery should minimise a number of hospitalisation cases, but its use is determined by many factors. It takes advantage of the latest advances in surgical care, enabling better use of highly costly specialised operating room equipment. This analysis of the day surgery system of the Slovak Republic stands on an examination of the five specialised fields-surgery, gynaecology, ophthalmology, otorhinolaryngology, and urology. The explored period covers the years 2009 to 2017. The whole analysis is divided into the two sections-the youth category and for the adult category. For each case, a hospitalisation ratio is computed. A map visualisation supports the analysis outcome. A quantification of the similarity relationships between the regions is done according to a Euclidean distance approach and it is illustrated through the heat map. The centremost region is the Žilina Region with distance at a level of 1.9821, meaning that it performs as the most similar region to a development of a hospitalisation ratio in the whole Slovak Republic regarding all the examined aspects. The findings introduce an important platform for a creation of regional and national health plans in the area of healthcare provision for the population of the country.
- MeSH
- ambulantní chirurgické výkony statistika a číselné údaje trendy MeSH
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- prostorová analýza MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladiství MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
- Geografické názvy
- Slovenská republika MeSH
The sustenance of humans and livestock depends on the protection of the soil. Consequently, the pollution of the soil with potentially toxic elements (PTEs) is of great concern to humanity. The objective of this study is to investigate the source apportionment, concentration levels and spatial distribution of PTEs in selected soils in Frýdek-Místek District of the Czech Republic. The total number of soil samples was 70 (topsoil 49 and 21 subsoils) and was analysed using a portable XRF machine. Contamination factor and the pollution index load were used for the assessment and interpreting the pollution and distribution of PTEs in the soils. The inverse distance weighting was used for the spatial evaluation of the PTEs. The results of the analysis showed that the area is composed of low-to-high pollution site. PTEs displayed spatial variation patterns. The average PTE concentration decreases in this Fe > Ti > Ba > Zr > Rb > Sr > Cr > Y>Cu > Ni > Th order for the topsoil and also decreases in this Fe > Ti > Zr > Ba > Rb > Sr > Cr > Y > Cu > Ni > and Th order for the subsoil. These PTEs Cr, Ni, Cu, Rb, Y, Zr, Ba, Th, and Fe were far above the baseline European average value and the World average value level, respectively. The source apportionment showed the dominance of Cr, Ni, Rb, Ti, Th, Zr, Cu, Fe in the topsoil, while the subsoil was dominated by all the PTEs (factor 1 to 6) except Ba. The study concludes that indiscriminate human activities have an enormous effect on soil pollution.
- MeSH
- hodnocení rizik MeSH
- látky znečišťující půdu analýza toxicita MeSH
- lidé MeSH
- monitorování životního prostředí MeSH
- prostorová analýza MeSH
- půda chemie MeSH
- těžké kovy analýza toxicita MeSH
- znečištění životního prostředí analýza statistika a číselné údaje MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
