As an important artificial neural network, associative memory model can be employed to mimic human thinking and machine intelligence. In this paper, first, a multi-valued many-to-many Gaussian associative memory model (M3GAM) is proposed by introducing the Gaussian unidirectional associative memory model (GUAM) and Gaussian bidirectional associative memory model (GBAM) into Hattori {et al}'s multi-module associative memory model ((MMA)2). Second, the M3GAM's asymptotical stability is proved theoretically in both synchronous and asynchronous update modes, which ensures that the stored patterns become the M3GAM's stable points. Third, by substituting the general similarity metric for the negative squared Euclidean distance in M3GAM, the generalized multi-valued many-to-many Gaussian associative memory model (GM3GAM) is presented, which makes the M3GAM become its special case. Finally, we investigate the M3GAM's application in association-based image retrieval, and the computer simulation results verify the M3GAM's robust performance.
Linear relations, containing measurement errors in input and output data, are taken into account in this paper. Parameters of these so-called \emph{errors-in-variables} (EIV) models can be estimated by minimizing the \emph{total least squares} (TLS) of the input-output disturbances. Such an estimate is highly non-linear. Moreover in some realistic situations, the errors cannot be considered as independent by nature. \emph{Weakly dependent} (α- and φ-mixing) disturbances, which are not necessarily stationary nor identically distributed, are considered in the EIV model. Asymptotic normality of the TLS estimate is proved under some reasonable stochastic assumptions on the errors. Derived asymptotic properties provide necessary basis for the validity of block-bootstrap procedures.
The variance of the number of lattice points inside the dilated bounded set $rD$ with random position in $\Bbb R^d$ has asymptotics $\sim r^{d-1}$ if the rotational average of the squared modulus of the Fourier transform of the set is $O(\rho ^{-d-1})$. The asymptotics follow from Wiener's Tauberian theorem.
Cíl práce: Prezentujeme kazuistiku pacienta, u kterého došlo k rozvoji oboustranného seminomu na podkladě intratubulární germinální neoplazie – neklasifikovatelný typ (IGCNU – intratubular germ cell neoplasia unclassified type). Kazuistika: Pacient s anamnézou seminomu levého varlete klinického stadia I a IGCNU po radikální orchiektomii a adjuvantní radioterapii byl odeslán k urologickému vyšetření pro suspektní tumor solitárního pravého varlete dle sonografického vyšetření. Indikovali jsme 3biopsii varlete, která prokázala přítomnost IGCNU. Následovala radikální orchiektomie, kde byl histologicky verifikován klasický seminom. Závěr: Intratubulární germinální neoplazie představuje vysoké riziko rozvoje invazivního germinálního tumoru varlete. Léčba zahrnuje radioterapii či chemoterapii cisplatinou. Alternativou je pečlivá dispenzarizace a pravidelné sonografické kontroly, zejména u pacientů se solitárním varletem, kteří chtějí zachovat fertilitu a endokrinní funkci. Biopsie kontralaterálního varlete u pacientů s germinálním tumorem k vyloučení IGCNU by měla být provedena v případě kryptorchizmu, poruchy spermiogeneze a atrofií varlete s objemem pod 12 ml, vhodná je rovněž u pacientů s mikrolitiázou varlete a předchozím výskytem IGCNU., Objective: We are presenting a case report of young man who developed an asynchronous bilateral seminoma based on an intratubular germ cell neoplasia of unclassified type (IGCNU). Case report: A patient, with history of a stage I seminoma of the left testis, based on an IGCNU of the left testis, after a radical orchidectomy and adjuvant radiotherapy, was referred to the urology clinic with a suspected tumor of the right testis. A testicular biopsy was made and the histological examination showed an IGCNU. A radical orchidectomy was performed and a seminoma was found. Conclusion: IGCNU is a precursor lesion of germ cell testicular tumors. Treatment of the IGCNU includes radiotherapy or chemotherapy with cisplatin. Surveillance remains an option for those with a solitary testicle who wish to preserve fertility and endocrine function. A contralateral testicular biopsy, in patients with a history of germ cell tumors, should be made in cases of cryptorchidism, poor spermatogenesis, and testicular atrophy with a testicular volume of less than 12 ml. Biopsy is also recommended in patients with testicular microlithiasis and history of ITGCNU., Jakub Musil, Daniel Bulíř, Jan Jandejsek, and Literatura
V našem článku prezentujeme případ 72letého pacienta s asynchronní nádorovou kvadruplicitou, z toho synchronní duplicitou urologických malignit. U tohoto pacienta byly postupně diagnostikovány a léčeny následující zhoubné nádory: seminom pravého varlete, kolorektální karcinom, seminom levého varlete a adenokarcinom prostaty., We present a case report of 72-year-old male with asynchronous cancer quadruplicity including synchronous duplicity of urological malignanties. He has been diagnosed and treated for seminoma of the right testis, colorectal carcinoma, seminoma of the left testis and adenocarcinoma of the prostate., Martin Klíma, Jan Schraml, Marek Broul, Martin Hlavička, Petr Skála, Martin Čegan, Martina Chodacká, and Literatura
This paper studies the leader-following consensus problem of second-order multi-agent systems with directed topologies. By employing the asynchronous sampled-data protocols, sufficient conditions for leader-following consensus with both constant velocity leader and variable velocity leader are derived. {Leader-following quasi-consensus can be achieved in multi-agent systems when all the agents sample the information asynchronously.} Numerical simulations are provided to verify the theoretical results.
Ateroskleróza jako zánětlivé postižení cévní stěny má více forem, které se vyskytují většinou současně. Klasická aterosklerotická léze charakterizovaná akumulací lipidů v subendoteliálním prostoru bývá často provázena změnami v hlubších vrstvách arteriální stěny, které jsou typické zmnožením extracelulární matrix a aktivací hladkosvalových buněk. Vlivem skladby rizikových faktorů může dominovat jeden nebo druhý typ postižení. Zatímco v patogenezi klasické formy aterosklerózy hrají zásadní roli aterogenní lipoproteiny (především třídy LDL), při rozvoji změn arteriální medie to jsou jiné rizikové faktory, např. hyperaktivita systému renin-angiotenzin-aldosteron (RAS). Ovlivněním těchto dvou základních mechanizmů prokazatelně zpomalujeme progresi cévních změn a příznivě ovlivňujeme prognózu nemocných. Důležitý je i fakt, že současné působení na tyto faktory má synergické působení doložené na úrovni experimentální i klinické. Důsledné využití možností nabízené intenzivním snižováním hladin aterogenních lipidů i nadměrné aktivity systému RAS snižuje riziko typických aterotrombotických komplikací (akutní koronární syndrom) i příhod podmíněných větší měrou změnami arteriální medie či hypertrofií levé komory srdeční (maligní arytmie, srdeční selhání). Tyto dva směry tak představují předpoklady úspěchu kardiovaskulární prevence. Klíčová slova: ateroskleróza – dyslipidemie – kardiovaskulární prevence – RAS – systémový zánět, Atherosclerosis as an inflammatory process affecting vessel wall has more forms usually occurring together. Classical atherosclerotic vascular lesion characterised by lipid accumulation in the subendothelial space is frequently accompanied by changes in deeper layers of arterial wall, in which increased extracellular tissue mass and smooth muscle cells activation represent the most prominent feature. Due to a specific constellation of risk factors the first or second pathology may be more expressed. While initiation and progression of classical atherosclerosis are mostly driven by lipoproteins (especially of LDL class) the most important factor of arterial media changes seem to be different risk factors e.g. hyperactivity of renin-angiotensin-aldosterone system (RAS). Influencing these two basic pathogenic mechanisms undoubtedly slows down the course of vascular changes and impacts positively on the prognosis of the patients. It is noteworthy, that simultaneous targeting of both of these mechanisms yields synergistic effects as evidenced both by experimental and clinical works. Using the opportunities offered by intensive lowering of atherogenic plasma lipids and over activation of the RAS system reduce not only the incidence of typical atherotromobotic complications (e.g. acute coronary syndrome) but also the events caused by changes of medial part of arterial wall or left myocardial ventricle (malignant arrhythmia, heart failure). These two strategies represent necessary conditions for successful cardiovascular prevention. Key words: atherosclerosis – cardiovascular prevention – dyslipidemia – RAS system – systemic inflammation, and Michal Vrablík
The atherogenic impact and functional capacity of LCAT was studied and discussed over a half century. This review aims to clarify the key points that may affect the final decision on whether LCAT is an anti-atherogenic or atherogenic factor. There are three main processes involving the efflux of free cholesterol from peripheral cells, LCAT action in intravascular pool where cholesterol esterification rate is under the control of HDL, LDL and VLDL subpopulations, and finally the destination of newly produced cholesteryl esters either to the catabolism in liver or to a futile cycle with apoB lipoproteins. The functionality of LCAT substantially depends on its mass together with the composition of the phospholipid bilayer as well as the saturation and the length of fatty acyls and other effectors about which we know yet nothing. Over the years, LCAT puzzle has been significantly supplemented but yet not so satisfactory as to enable how to manipulate LCAT in order to prevent cardiometabolic events. It reminds the butterfly effect when only a moderate change in the process of transformation free cholesterol to cholesteryl esters may cause a crucial turn in the intended target. On the other hand, two biomarkers - FERHDL (fractional esterification rate in HDL) and AIP [log(TG/HDL-C)] can offer a benefit to identify the risk of cardiovascular disease (CVD). They both reflect the rate of cholesterol esterification by LCAT and the composition of lipoprotein subpopulations that controls this rate. In clinical practice, AIP can be calculated from the routine lipid profile with help of AIP calculator www.biomed.cas.cz/fgu/aip/calculator.php., M. Dobiášová., and Obsahuje bibliografii
a1_In this study we compared several parameters characterizing differences in the lipoprotein profile between members of families with a positive or negative family history of coronary artery disease (CAD). In addition to regular parameters such as the body mass index (BMI), total plasma cholesterol (TC), low density (LDL-C) and high density (HDL-C) cholesterol and triglycerides (TG) we estimated the fractional esterification rate of cholesterol in apoB lipoprotein-depleted plasma (FERHDL) which reflects HDL and LDL particle size distribution. A prevalence of smaller particles for the atherogenic profile of plasma lipoproteins is typical. Log (TG/HDL-C) as a newly established atherogenic index of plasma (AIP) was calculated and correlated with other parameters. The cohort in the study consisted of 29 young (< 54 years old) male survivors of myocardial infarction (MI), their spouses and at least one offspring (MI group; n=116). The control group consisted of 29 apparently healthy men with no family history of premature CAD in three generations, their spouses and at least one offspring (control group; n=124). MI families had significantly higher BMI than the controls, with the exception of spouses. Plasma TC did not significantly differ between MI and the controls. MI spouses had significantly higher TG. Higher LDL-C had MI survivors only, while lower HDL-C had both MI survivors and their spouses compared to the controls. FERHDL was significantly higher in all the MI subgroups (probands 25.85±1.22, spouses 21.55±2.05, their daughters 16.93±1.18 and sons 19.05±1.33 %/h) compared to their respective controls (men 20.80±1.52, spouses 14.70±0.98, daughters 13.23±0.74, sons 15.7±0.76 %/h, p<0.01 to p<0.05). Log (TG/HDL-C) ranged from negative values in control subjects to positive values in MI probands., a2_High correlation between FERHDL and Log (TG/HDL-C) (r = 0.80, p<0.0001) confirmed close interactions among TG, HDL-C and cholesterol esterification rate. The finding of significantly higher values of FERHDL and Log (TG/HDL-C) indicate higher incidence of atherogenic lipoprotein phenotype in members of MI families. The possibility that, in addition to genetic factors, a shared environment likely contributes to the familial aggregation of CAD risk factors is supported by a significant correlation of the FERHDL values within spousal pairs (control pairs: r = 0.51 p<0.01, MI pairs: r = 0.41 p<0.05)., M. Dobiášová, K. Rašlová,H. Rauchová, B. Vohnout, K. Ptáčková, J. Frohlich., and Obsahuje bibliografii