Numerical correlations
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... Recurrence Formula 219 -- 5.5 Complex Arithmetic 225 -- 5.6 Quadratic and Cubic Equations 227 -- 5.7 Numerical ... ... 685 -- 13.9 Computing Fourier Integrals Using the FFT 692 -- 13.10 Wavelet Transforms 699 -- 13.11 Numerical ... ... 730 -- 14.4 Contingency Table Analysis of Two Distributions 741 -- 14.5 Linear Correlation 745 -- 14.6 ... ... Nonparametric or Rank Correlation 748 -- 14.7 Information-Theoretic Properties of Distributions 754 ... ... Delaunay Triangulation 1141 -- 21.8 Quadtrees and Octrees: Storing Geometrical Objects 1149 -- 22 Less-Numerical ...
3rd ed. xxi, 1235 s. : il. ; 27 cm + 1 CD-ROM
- MeSH
- matematické výpočty počítačové MeSH
- matematika MeSH
- numerická analýza pomocí počítače * MeSH
- Publikační typ
- monografie MeSH
Fluorescence methods are widely used in studies of biological and model membranes. The dynamics of membrane fluorescent markers in their ground and excited electronic states and correlations with their molecular surrounding within the fully hydrated phospholipid bilayer are still not well understood. In the present work, Quantum Mechanical (QM) calculations and Molecular Dynamics (MD) simulations are used to characterize location and interactions of two membrane polarity probes (Prodan; 6-propionyl-2-dimethylaminonaphthalene and its derivative Laurdan; 2-dimethylamino-6-lauroylnaphthalene) with the dioleoylphosphatidylcholine (DOPC) lipid bilayer model. MD simulations with fluorophores in ground and excited states are found to be a useful tool to analyze the fluorescent dye dynamics and their immediate vicinity. The results of QM calculations and MD simulations are in excellent agreement with available experimental data. The calculation shows that the two amphiphilic dyes initially placed in bulk water diffuse within 10 ns towards their final location in the lipid bilayer. Analysis of solvent relaxation process in the aqueous phase occurs on the picoseconds timescale whereas it takes nanoseconds at the lipid/water interface. Four different relaxation time constants, corresponding to different relaxation processes, where observed when the dyes were embedded into the membrane.
[1st ed.] VII, 334 s. : bar.fot., obr., tab., grafy ; 26 cm
AIM: To perform a comparative analysis of clinicopathological correlations of cyclooxygenase-2 (COX-2) expression in pancreatic cancer, examined by monoclonal and polyclonal antibodies. METHODS: The COX-2 expression in 85 resection specimens of pancreatic ductal adenocarcinoma was immunohistochemically examined using both monoclonal and polyclonal antibodies. The final immunoscores were obtained by multiplying the percentage of positive cells with the numeric score reflecting the staining intensity. COX-2 expression levels were classified into three categories (0, 1+, and 2+) and the clinicopathological correlations were statistically evaluated and analyzed. RESULTS: The positive tumor expression rates of COX-2 were 80.5% using monoclonal antibody and 69.4% using polyclonal antibody. In the Kaplan-Meier analysis, no significant correlations were found between levels of COX-2 expression and overall survival (OS), but trends to longer OS were found in COX-2 negative cases using monoclonal antibody. Significantly longer disease free survival was revealed in COX-2 negative cases using monoclonal antibody (P = 0.019). No correlations between COX-2 expression levels and grade (G), tumor (T) status and nodal (N) status were demonstrated. Low histological grade showed a strong association with a longer OS (P < 0.001). Correlation of survival and T status revealed a shorter OS in T3 tumors, but the results reached only marginal statistical significance (P = 0.070). In the multivariate Cox proportional hazards regression model, histological grade, T and N status remained valuable predictors of a worse survival with borderline significance for T [hazards ratio (HR) = 4.18 for G (if G = 3, P < 0.001); HR = 1.64 for T (if T = 3, P = 0.065); HR = 2.53 for N (if N = 1, P = 0.006)]. Higher grade, T or N status was associated with a worse OS. CONCLUSION: The immunohistochemically assessed level of COX-2 expression does not seem to represent a valuable independent prognostic factor and is not superior to the conventional prognostic factors.
- MeSH
- cyklooxygenasa 2 biosyntéza MeSH
- dospělí MeSH
- imunohistochemie metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- monoklonální protilátky metabolismus MeSH
- nádory slinivky břišní enzymologie chirurgie MeSH
- prognóza MeSH
- proporcionální rizikové modely MeSH
- regulace genové exprese enzymů MeSH
- regulace genové exprese u nádorů MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- vývody pankreatu enzymologie patologie 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
- srovnávací studie MeSH
To provide basic data on the local differences in density of microvessels between various parts of the human brain, including representative grey and white matter structures of the cerebral hemispheres, the brain stem and the cerebellum, we quantified the numerical density NV and the length density LV of microvessels in two human brains. We aimed to correlate the density of microvessels with previously published data on their preferential orientation (anisotropy). Microvessels were identified using immunohistochemistry for laminin in 32 samples harvested from the following brain regions of two adult individuals: the cortex of the telencephalon supplied by the anterior, middle, and posterior cerebral artery; the basal ganglia (putamen and globus pallidus); the thalamus; the subcortical white matter of the telencephalon; the internal capsule; the pons; the cerebellar cortex; and the cerebellar white matter. NV was calculated from the number of vascular branching points and their valence, which were assessed using the optical disector in 20-μm-thick sections. LV was estimated using counting frames applied to routine sections with randomized cutting planes. After correction for shrinkage, NV in the cerebral cortex was 1311±326mm-3 (mean±SD) and LV was 255±119mm-2. Similarly, in subcortical grey matter (which included the basal ganglia and thalamus), NV was 1350±445mm-3 and LV was 328±117mm-2. The vascular networks of cortical and subcortical grey matter were comparable. Their densities were greater than in the white matter, with NV=222±147mm-3 and LV=160±96mm-2. NV was moderately correlated with LV. In parts of brain with greater NV, blood vessels lacked a preferential orientation. Our data were in agreement with other studies on microvessel density focused on specific brain regions, but showed a greater variability, thus mapping the basic differences among various parts of brain. To facilitate the planning of other studies on brain vascularity and to support the development of computational models of human brain circulation based on real microvascular morphology; stereological data in form of continuous variables are made available as supplements.
Cíl: cílem práce bylo podle stanovených parametrů vstupní rány a výsledného uložení kovového nitroočního tělesa stanovit korelační závislost obou veličin. Materiál a metodika: do retrospektivní studie bylo zařazeno 50 pacientů (50 očí) s otevřeným poraněním oka a přítomným kovovým nitroočním tělesem. Klinicky zjištěná data vstupní rány a výsledného uložení cizího nitroočního tělesa (CNT) byla převedena do trojrozměrně definovaných parametrů pomocí počítačového modelu. Oba parametry byly statisticky zpracovány metodou korelační analýzy se stanovením korelačního koeficientu a koeficientu determinace. Výsledky: mírou korelace mezi dvěma proměnnými je tzv. koeficient korelace. Koeficient nabývá hodnot od -1 do +1. Čím je jeho hodnota bližší plus nebo minus jedné, tím více jsou veličiny korelované. Koeficient determinace nabývá hodnot od 0 do +1. Čím více se výsledky blíží hodnotě +1, tím lépe model popisuje závislost mezi dvěma veličinami. Výsledky zpracované korelační analýzou prokázaly nejvyšší hodnoty korelačního koeficientu, resp. koeficientu determinace 0,454, resp. 0,6411. Závěr: z výsledků provedené korelační analýzy vyplývá, že pomocí znalosti souřadnic vstupu nedokážeme predikovat konečné souřadnice tělesa v oku. Tyto dvě proměnné jsou navzájem nekorelované a proto přesná predikce konečné polohy tělesa v oku není možná. Na výsledné umístění kovového CNT po vstupu do oka mají zřejmě vlivy biofyzikální faktory, které nebyly zahrnuty do studie.
Aim: The aim of this study was to establish the correlation coefficient between given parameters of the entering wound and final position of the metallic intraocular foreign body. Material and methods: fifty patients (50 eyes) with a penetrating injury of the eye and present metallic intraocular foreign body were included in this study. Clinically found data of the entering wound and final position of the intraocular foreign body (IFB) as well were transformed with a computer model into the three-dimensional parameters. Both chirurparameters were statistically evaluated by means of correlation analysis, and correlation coefficient and determination coefficient were calculated. Results: The extent of correlation between two variables is called correlation coefficient. The coefficient values range between -1 to +1. The closer is the calculated value to ranges (to -1 or to +1) the more are the two variables more correlated. The coefficient of determination values range from 0 to +1. The closer the results are to +1, the better the model describes the dependence between the two variables. The results obtained by means of correlation analysis were for the correlation coefficient 0.454, and for the coefficient of determination 0.6411 respectively. Results: Results of the correlation analysis show that the knowledge of coordinates of the entering wound has no prediction value for final position of the foreign body in the eye. These two variables are not correlated and so the accurate final position of the foreign body cannot be predicted. The final position of the intraocular metallic foreign body is probably influenced by biophysical factors not included in this study.
In sperms of infertile men is higher incidence of chromosome aneuploidy. Consequently for embryos developed from these sperms PGD is indicated. Material and methods: In our laboratory were made 331 PGD cycles. 25 of them were counted among group of indication, in which embryos were fertlized with sperm after TESA. PGD was performed on blastomeres from three-day old embryo in two hybridisation cycles. During this procedure we evaluated 8 chromosomes (13, 15, 16, 18, 21, 22, X, Y). Results: Total mean age of patients with spermatogenic failure was 32.24. This group contained 25 couples and 184 embryos were evaluated. From this amount 75 preimplantation embryos did not show numerical aberrations for detected chromosomes and 22 of them were transferred. 31.8 % patients were pregnant (this number related to embryotransferr). On the other side more than 59 % investigated blastomeres showed a numerical chromosomal abnormality. Monosomy chromosome 16 and aneuploidy of sex chromosomes were observed the most frequently. Conclusions: The incidence of aneuploidies in sperm after TESA should correlate with incidence of genetic abnormalities in embryo. Our results are similar to literature, where sex chromosomes aneuploidies the most frequently occur in sperms after TESA. In these studies the chromosome 16 was not analysed. The higher incidence of monosomy of this chromosome can be caused by low number of evaluated blastomeres.
V prospektivní studii byly srovnány výsledky několika postupů vyšetření frakce oxidu dusnatého ve vydechovaném vzduchu (FE NO ). Soubor tvořilo 82 dětí (44 chlapců) s alergickou rýmou a/nebo průduškovým as tmatem. V souladu s doporučeními byly u dětí mladších než 12 let (věk 4,9 až 11,8 let, N =36) a u starších dětí (věk 12,2 až 18,7 let, N = 46) použity věkově příslušné techniky a metody vyhodnocení. Ustál ené koncentrace na křivkách FE NO -čas získaných technikou jednoho výdechu rychlostí 50 ml/s do chemiluminiscenčního přístroje Ecomedics postupem podle doporučení odborných společností byly o 34 % vyšší než výsledky, které automaticky vyhodnotil software přístroje v intervalu 2– 4 s od zahájení výdechu. Naopak u starších dětí nebyly pozorovány rozdíly mezi ustálenými koncentracemi a koncentracemi v konstantním intervalu 7–10 s od zahájení výdechu. V obou věkových skupinách byla systematická od chylka mezi výsledky techniky jednoho výdechu do přístroje Ecom edics a elektrochemického monitoru NIOX MINO malá (14 % u starších a 21 % u mladších dětí). Rozptyl diferencí byl ale značný a v indi viduálních případech nelze vyloučit rozdíl vyšší ne ž 100 %. Technika klidového dýchání do přístroje Ecomedics poskytuje hodnoty FE NO, které jsou 3 až 4krát nižší, ale dobře korelují s výsl edky techniky jednoho výdechu.
In a prospective clinical study with 82 children and adoles cents (44 males) with corticosteroid-treated allergic rhinitis and/o r asthma, several techniques for measurement of fractional exhaled nitric oxide (FE NO ) were compared. In agreement with the published guidelines, different techniques and evaluation methods were used in younger (4.9–11.8 yr, N = 36) and older children (12.2–18.7 yr, N = 46), respect ively. Regarding the single-breath chemiluminiscence measurement at the expiratory flow rate of 50 mL/s performed with the Ecomedics analyzer in children younger than 12 yr, the guideline-derived plateau FE NO concentrations evaluated at variable time intervals of exhalation were 34% higher than the concentrations from the fixed time interval of 2–4 s used by the software of the analyzer. Contrary to that, the FE NO concentrations of older children calculated in the fixed interval of 7-10 s represent the plateau values. In both groups of children, the mean differen ce between the FE NO concentrations from Ecomedics and the results of electrochemical monitor NIOX MINO was less than 21 %. In individual patients h owever, a higher than 100 % difference can not be excluded. Chemiluminiscen ce measurement using the tidal breathing technique gave 3 to 4-fold lower FE NO values compared to single exhalation but the results of both techniques were highly correlated.
- MeSH
- bronchiální astma diagnóza imunologie MeSH
- diagnostické techniky dýchacího ústrojí přístrojové vybavení využití MeSH
- dítě MeSH
- financování organizované MeSH
- lidé MeSH
- luminiscence diagnostické užití MeSH
- numerická analýza pomocí počítače přístrojové vybavení MeSH
- oxid dusnatý izolace a purifikace MeSH
- prospektivní studie MeSH
- respirační funkční testy metody využití MeSH
- výměna plynů v plicích fyziologie imunologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
Estimating causal interactions in complex dynamical systems is an important problem encountered in many fields of current science. While a theoretical solution for detecting the causal interactions has been previously formulated in the framework of prediction improvement, it generally requires the computation of high-dimensional information functionals-a situation invoking the curse of dimensionality with increasing network size. Recently, several methods have been proposed to alleviate this problem, based on iterative procedures for the assessment of conditional (in)dependences. In the current work, we bring a comparison of several such prominent approaches. This is done both by theoretical comparison of the algorithms using a formulation in a common framework and by numerical simulations including realistic complex coupling patterns. The theoretical analysis highlights the key similarities and differences between the algorithms, hinting on their comparative strengths and weaknesses. The method assumptions and specific properties such as false positive control and order-dependence are discussed. Numerical simulations suggest that while the accuracy of most of the algorithms is almost indistinguishable, there are substantial differences in their computational demands, ranging theoretically from polynomial to exponential complexity and leading to substantial differences in computation time in realistic scenarios depending on the density and size of networks. Based on the analysis of the algorithms and numerical simulations, we propose a hybrid approach providing competitive accuracy with improved computational efficiency.
