The Tea4-PP1 landmark promotes local growth by dual Cdc42 GEF recruitment and GAP exclusion.

Cell polarization relies on small GTPases, such as Cdc42, which can break symmetry through self-organizing principles, and landmarks that define the axis of polarity. In fission yeast, microtubules deliver the Tea1-Tea4 complex to mark cell poles for growth, but how this complex activates Cdc42 is unknown. Here, we show that ectopic targeting of Tea4 to cell sides promotes the local activation of Cdc42 and cell growth. This activity requires that Tea4 binds the type I phosphatase (PP1) catalytic subunit Dis2 or Sds21, and ectopic targeting of either catalytic subunit is similarly instructive for growth. The Cdc42 guanine-nucleotide-exchange factor Gef1 and the GTPase-activating protein Rga4 are required for Tea4-PP1-dependent ectopic growth. Gef1 is recruited to ectopic Tea4 and Dis2 locations to promote Cdc42 activation. By contrast, Rga4 is locally excluded by Tea4, and its forced colocalization with Tea4 blocks ectopic growth, indicating that Rga4 must be present, but at sites distinct from Tea4. Thus, a Tea4-PP1 landmark promotes local Cdc42 activation and growth both through Cdc42 GEF recruitment and by creating a local trough in a Cdc42 GAP

Broadband parametric processes in χ^(2) nonlinear photonic crystals

International audienceWe develop a general model, based on a (2+1)D unidirectional pulse propagation equation, for describing broadband noncollinear parametric interactions in two-dimensional quadratic lattices. We apply it to the analysis of twin-beam optical parametric generation in hexagonally poled LiTaO 3 , gaining further insights into experimental observations

Optical fibre sensors

Cieľom práce je detailne preskúmať možnosti vlákna ako optický senzor. Práca sa ďalej zaoberá problematikou optických vláknových senzorov, ich rozdelením a použitím. Popisuje najznámejšie typy, ich výhody a nevýhody. V úvode je spomenutý úvod do optických vlákien, popis najznámejších lineárnych a nelineárnych javov prebiehajúcich vo vlákne a vývoj optických senzorov. Senzory sú prehľadne rozdelené podľa použitia a spoločnej vlastnosti. Práca sa ďalej venuje distribuovaným vláknovým senzorom, zahrnuté sú v nej dva odlišné návrhy týchto senzorov a takisto sú spomenuté základné princípy pri návrhoch distribuovaných senzorov. Na konci práce je senzor využívajúci Brillouinov rozptyl na meranie vibrácii odsimulovaný v simulačnom programe a vyvodené sú závery z výsledkov spektrálnej analýzy.The aim of this thesis is to examine in detail the possibility of fiber as optical sensor. This work deals with optical fiber sensors, their distribution and use. Describes the most renowned types, their advantages and disadvantages. At the beginning of this thesis there is an introduction to optical fibers, description of well-known linear and nonlinear phenomena occurring in them, development of optical sensors. Sensors are cleraly divided by usage and common attributes. The paper focuses on distributed optical fiber sensors and includes two different designs of these sensors there are also basic principles in designing distributed sensors. At the end of the work, the sensor using Brillouin scattering measuring vibration is simulated in the simulation program. Viewed transmitted signal spectra are shown and conclusions of results are drawn.

Impact assessment of split ratios on passive optical network

Práca sa zaoberá najnovším štandardom pasívnych optických sietí NG-PON2, jeho vrstvovým modelom, ktorého súčasťou je ochranné zabezpečenie pri prenose po optickom médiu. Implementuje a popisuje simulačné prostredie. Posudzuje vplyv deliaceho pomeru pomocou tohto prostredia vytvoreného z definovaného modelu, pričom porovnáva rôzne scenáre použitia. Diskutuje možné zdroje chýb simulačného modelu v porovnaní s reálnym.This thesis deals with the most recent passive optical network standard NG-PON2, describes the sublayer model which includes error correction coding during propagation in optical fibres. Assesses the impact of split ratios using the simulation environment created from defined model and compares various scenarios. Discusses possible sources of errors of simulation model in compare to real deployment.

Monatomic phase change memory

Phase change memory has been developed into a mature technology capable of storing information in a fast and non-volatile way, with potential for neuromorphic computing applications. However, its future impact in electronics depends crucially on how the materials at the core of this technology adapt to the requirements arising from continued scaling towards higher device densities. A common strategy to finetune the properties of phase change memory materials, reaching reasonable thermal stability in optical data storage, relies on mixing precise amounts of different dopants, resulting often in quaternary or even more complicated compounds. Here we show how the simplest material imaginable, a single element (in this case, antimony), can become a valid alternative when confined in extremely small volumes. This compositional simplification eliminates problems related to unwanted deviations from the optimized stoichiometry in the switching volume, which become increasingly pressing when devices are aggressively miniaturized. Removing compositional optimization issues may allow one to capitalize on nanosize effects in information storage

crystal structure and de and rehydration behaviorof two new chloride containing zeolitic imidazolate frameworks

A previously unknown solid phase in the zinc-imidazole system relevant for the synthesis of ZIF-8 was obtained by adding a small excess of methylimidazole (Hmim) to a diluted zinc chloride solution. By chemical and thermal analyses, a composition of Zn3(mim)5ClH2O·xH2O with x = 0.74 was determined and the compound denoted as ZIF-yqt hydrate. The crystal structure was solved from laboratory X-ray powder diffraction (XRPD) data. ZIF-yqt hydrate crystallizes in a C-centered monoclinic unit cell with space group C2/c (15) and lattice parameters of a = 13.1574(3) A, b = 16.4959(3) A, c = 13.6403(3) A, and β = 119.166(2)°. The structure is built up from Zn(mim)4/2 and Zn(mim)3/2(Cl0.5H2O0.5)1/1 units forming a self-penetrating yqt1 type net. IR spectroscopy was employed to confirm the presence of water in the coordination sphere of zinc. In addition, noncoordinated water is situated in the voids of this net. By heating, ZIF-yqt hydrate can be completely dehydrated resulting in the formation of anhydrous Zn3(mim..

Weighted principal component analysis for compositional data: application example for the water chemistry of the Arno river (Tuscany, central Italy)

Data collected for the investigation of the environmental and ecological characteristics of a river basin are often in the form of a large three-way array; hence, a particular version of the Tucker model could be applied to gather more information contained in such complex geochemical systems. Indeed, when the data are in compositional form, more attention must be given to the analysis of the numerical data. Recently, the Tucker3 model has been proposed to analyze compositional data characterized by a three-way structure. In this work, a particular version of the Tucker model, known as the weighted\ud principal component analysis, was used to analyze water samples collected from the Arno river (Tuscany, central Italy)\ud in order to evaluate the method’s effectiveness. Several graphical displays have been developed to allow an accurate and complete interpretation of results

Methodology for the Accurate Measurement of the Power Dissipated by Braking Rheostats

The energy efficiency of transportation is a crucial point for the rail and metro system today. The optimized recovery of the energy provided by the electrical braking can lead to savings of about 10% to 30%. Such figures can be reached by infrastructure measures which allow the recovery of the breaking energy that is not directly consumed by the rail system and dissipated in rheostat resistors. A methodology for the accurate estimate of such energy is valuable for a reliable evaluation of the cost-benefit ratio associated with the infrastructural investment. The energy can be estimated by measuring a braking current flowing in the rheostats. The varying duty-cycle associated with the high dynamic variation, from zero to thousands of amperes, makes the current measurement very challenging. Moreover, the digitization of such waveforms introduces systematic errors that affect the energy estimation. To overcome these issues, this paper proposes a technique to measure the power and energy dissipated by the rheostat of a DC operated train with high accuracy. By means of an accurate model of the electrical braking circuit (chopper and rheostat) and the frequency characterization of the current transducer, a correction coefficient as a function of the duty-cycle is estimated. The method is then applied to data recorded during a measurement campaign performed on-board a 1.5 kV train of Metro de Madrid during normal operation. Using the proposed technique, the estimation of the dissipated braking energy is improved by 20%

Early and unrestricted access to high-efficacy disease-modifying therapies: a consensus to optimize benefits for people living with multiple sclerosis

Healthcare system; Multiple sclerosis; PharmacoeconomicsSistema de atención de la salud; Esclerosis múltiple; FarmacoeconomíaSistema d'atenció de la salut; Esclerosi múltiple; FarmacoeconomiaEarly intervention with high-efficacy disease-modifying therapy (HE DMT) may be the best strategy to delay irreversible neurological damage and progression of multiple sclerosis (MS). In European healthcare systems, however, patient access to HE DMTs in MS is often restricted to later stages of the disease due to restrictions in reimbursement despite broader regulatory labels. Although not every patient should be treated with HE DMTs at the initial stages of the disease, early and unrestricted access to HE DMTs with a positive benefit–risk profile and a reasonable value proposition will provide the freedom of choice for an appropriate treatment based on a shared decision between expert physicians and patients. This will further optimize outcomes and facilitate efficient resource allocation and sustainability in healthcare systems and society.Novartis facilitated two advisory boards on ‘Unrestricted access for RMS therapy and optimal patient outcome’ with physicians, health economists and patient groups to collect insights on the access to MS therapies across Europe as well as on the therapeutic strategy in MS with high efficacy early. These insights contributed to the manuscript content, which was then suggested for publication on a voluntary basis by the experts who wished to be authors. The content is owned and driven by the authors. The Sponsor had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication