Electromagnetic energy in a dispersive metamaterial

An expression for the electromagnetic field energy density in a dispersive lossy left-handed metamaterial, consisting of an array of split-ring resonators and an array of wires, is derived. An electromagnetic field with general time dependence is considered. The outcome is compared with previously published results. In the absence of losses, agreement with the general result for the energy density in a dispersive material is obtained. The formulae are verified using the finite-difference time-domain numerical method. The applicability of two commonly used permeability models to the problem of calculating the energy stored in an array of split-ring resonators is discussed

The role of echocardiography in the diagnosis of fetal and pediatric cardiac tumors

В исторически план развитието на образните методи на изследване при сърдечните тумори позволи преминаването от аутопсионна към прижизнено поставена диагноза. Ехокардиографията е лесно достъпен, неинвазивен и високо информативен диагностичен метод на първи избор.Представени са възможностите на съвременното комплексно ехокардиографско изследване за ранно, включително и пренатално, откриване на туморите на сърцето, придружаващите сърдечни аномалии и извършването на коректна хемодинамична оценка. Включени са и наши собствени наблюдения на пациенти с различни по вид сърдечни тумори, диагностицирани както фетално, така и след раждането.Ехокардиографското изследване е утвърден, бърз, удобен и информативен метод за пре- и постнатално диагностициране на сърдечните тумори в детската възраст, както и за тяхното пре- и постоперативно проследяване.The development of different imaging techniques allows the diagnosis of cardiac tumors to be made before the death of a person, and not as it used to be made - following a post mortem. Echocardiography is easily available, noninvasive and a highly informative diagnostic method of choice.We`re presenting the possibilities of current echocardiography examination for the early, including prenatal, diagnosis of cardiac tumors, concomitant congenital heart diseases and hemodynamic evaluation. In this report we also include the observations of our own patients with different kinds of cardiac tumors, which were diagnosed prenatally and after birth. Echocardiography is an approved, quick, convenient and informative prenatal, and postnatal, diagnostic method for cardiac tumors in childhood, as well as for their preoperative and postoperative follow-up

Reply to Brunet and Doolittle: Both selected effect and causal role elements can influence human biology and disease

We agree with Brunet and Doolittle (1) on the utility of distinguishing the evolutionarily selected effects (SE) of some genomic elements from the causal roles (CR) of other elements that lack signatures of selection (1⇓⇓–4). DNA sequences identified by biochemical approaches include both SE and CR elements, and genetic variation in both has been implicated in human traits and disease susceptibility. We thus view the Encyclopedia of DNA Elements (ENCODE) catalog and similar data resources as important foundations for understanding the DNA elements and molecular mechanisms underlying human biology and disease

Defining functional DNA elements in the human genome

With the completion of the human genome sequence, attention turned to identifying and annotating its functional DNA elements. As a complement to genetic and comparative genomics approaches, the Encyclopedia of DNA Elements Project was launched to contribute maps of RNA transcripts, transcriptional regulator binding sites, and chromatin states in many cell types. The resulting genome-wide data reveal sites of biochemical activity with high positional resolution and cell type specificity that facilitate studies of gene regulation and interpretation of noncoding variants associated with human disease. However, the biochemically active regions cover a much larger fraction of the genome than do evolutionarily conserved regions, raising the question of whether nonconserved but biochemically active regions are truly functional. Here, we review the strengths and limitations of biochemical, evolutionary, and genetic approaches for defining functional DNA segments, potential sources for the observed differences in estimated genomic coverage, and the biological implications of these discrepancies. We also analyze the relationship between signal intensity, genomic coverage, and evolutionary conservation. Our results reinforce the principle that each approach provides complementary information and that we need to use combinations of all three to elucidate genome function in human biology and disease

Electrochemical detection of Nitrofural in the presence of sodium amminepentacyanoferrate (II)

The present study deals with the development of a new qualitative electrochemical analytic test for detecting the chemotherapeutic agent Nitrofural. The combination of sodium amminepentacyanoferrate(II) and electric power, provided by a 9V battery, was successfully implemented for the analysis of the medicine in question

L’elefant a l’habitació. Fer propaganda de la ciència com a motor de creixement econòmic és una estratègia condemnada al fracàs a llarg termini

En el número 51 de la revista L'Espill trobaràs un dossier monogràfic sobre "Consideracions intempestives sobre els Països Catalans", amb contribucions d'Antoni Furió, Gustau Muñoz, Pau Viciano, Ferran Garcia-Oliver i Antoni Rico. A més, articles de Salvador Giner, Terry Eagleton, Georgi K. Marinov, Paola Lo Cascio, Toni Mollà, Gonçal López Pampló i Àlex Broch, així com la correspondència entre Josep Iborra i Josep Garcia Richart, un full de dietari d'Enric Balaguer i una conversa amb Josep Piera, per Ferran Garcia-Oliver

Genome Sequence of Magnetospirillum magnetotacticum Strain MS-1

Here, we report the genome sequence of Magnetospirillum magnetotacticum strain MS-1, which consists of of 36 contigs and 4,136 protein-coding genes

Therapeutic approach to idiopathic hypertrophic cardiomyopathy

Идиопатичната хипертрофична кардиомиопатия е рядко срещана в детска възраст с висок потенциален риск от фатален край. Отличителен белег е миокардната хипертрофия при липса на хемодинамична причина. От първия описан случай на експериментално лечение на кърмаче през 1971 г. бета-блокерите имат водеща роля в медикаментозното лечение с вариации в дозовите режими. По последни литературни данни и клинични проучвания употребата на високи дози бета-блокер неоспоримо показва значим процент на преживяемост в дългосрочен план.Представяме клиничен случай на 11-месечно кърмаче, което постъпва в нашата клиника с данни за сърдечна недостатъчност. От проведените образни изследвания - рентгенография на гръден кош и ехокардиография, се установи изразена симетрична хипертрофична необструктивна кардиомиопатия. Започна се медикаментозно лечение с пропранолол в постепенно покачваща се доза до 5 мг / кг / 24 часа. Няколко седмици по-късно при контролно ехокардиографско изследване се установи значително подобрение в диастолната функция на лява камера с известна регресия в хипертрофията на миокарда. Контролираното прилагане на високи дози бета-блокери би могло съществено да подобри прогнозата и дългосрочната преживяемост при пациентите с идиопатична хипертрофична кардиомиопатия.Idiopathic hypertrophic cardiomyopathy is a rare disease in childhood with a high potential of a lethal outcome. The hallmark of the disorder is myocardial hypertrophy that occurs in the absence of an obvious hemodynamic stimulus. Since the first case of an experimental treatment of an infant described in 1971, beta blockers have become one of the leading medication options with variations of the dose regimens. According to the current literature data and clinical trials the use of beta blockers in high doses is consistent with a high percentage of survival.We`re presenting a clinical case of an 11-month old infant, who was admitted to our clinic with symptoms of congestive cardiac failure. The chest radiography and echocardiography results showed a severe symmetric hypertrophic cardiomyopathy without an obstruction in the left ventricular outflow tract. The treatment was started with Propranolol in a titrating dose until reaching the dose of 5mg/kg/24hours. Several weeks later, echocardiography examination showed a significant improvement in the left ventricle diastolic function with some degree of regression of myocardial hypertrophy.The use of high doses of beta blockers together with the monitoring of the clinical state could improve the prognosis and survival in patients with idiopathic hypertrophic cardiomyopathy

Percolation in the Harmonic Crystal and Voter Model in three dimensions

We investigate the site percolation transition in two strongly correlated systems in three dimensions: the massless harmonic crystal and the voter model. In the first case we start with a Gibbs measure for the potential, $U=\frac{J}{2} \sum_{} (\phi(x) - \phi(y))^2$, $x,y \in \mathbb{Z}^3$, $J > 0$ and $\phi(x) \in \mathbb{R}$, a scalar height variable, and define occupation variables $\rho_h(x) =1,(0)$ for $\phi(x) > h (<h)$. The probability $p$ of a site being occupied, is then a function of $h$. In the voter model we consider the stationary measure, in which each site is either occupied or empty, with probability $p$. In both cases the truncated pair correlation of the occupation variables, $G(x-y)$, decays asymptotically like $|x-y|^{-1}$. Using some novel Monte Carlo simulation methods and finite size scaling we find accurate values of $p_c$ as well as the critical exponents for these systems. The latter are different from that of independent percolation in $d=3$, as expected from the work of Weinrib and Halperin [WH] for the percolation transition of systems with $G(r) \sim r^{-a}$ [A. Weinrib and B. Halperin, Phys. Rev. B 27, 413 (1983)]. In particular the correlation length exponent $\nu$ is very close to the predicted value of 2 supporting the conjecture by WH that $\nu= \frac{2}{a}$ is exact.Comment: 8 figures. new version significantly different from the old one, includes new results, figures et