Chronic Implantation of Intravascular Cardioverter Defibrillator in a Canine Model

INTRODUCTION: A percutaneously placed implantable intravascular defibrillator (PICD) has been developed with a right ventricular (RV) single-coil lead and titanium electrodes in the superior vena cava (SVC) and the inferior vena cava (IVC). This study evaluated implant techniques, device stability, and anchor histology of the PICD over 9 months in a canine model. METHODS: Twenty-four hounds (wt = 30-55 kg) were anesthetized and a custom sheath introduced into the right femoral vein. The PICD was advanced over a wire and positioned with the titanium electrodes (cathodes) in the SVC and the IVC. A nitinol anchor secured the device in the jugular. The RV lead was positioned in the RV apex and screwed into place. The catheters, wires, and sheath were removed with an average implant time of 14 minutes. In one group of animals (n = 13), serial venograms were performed at 7 days, 14 days, and 28 days. In a second group (n = 6) and third group (n = 5), venograms were also performed at 90 days and 270 days, respectively. Six canines were sacrificed and anchor histologic examination done at 90 days. RESULTS: All implants were successful with no surgical complications observed. Devices (N = 24) remained appropriately positioned with no anchor migration. Histology at 90 days showed 98% endothelialization of the anchor. Venograms revealed patent IVC and jugular veins in all animals at every time point examined. CONCLUSIONS: The PICD can be rapidly and chronically implanted in animals. Long-term intravascular defibrillator placement is feasible in a canine model

Laminar analysis of the slow wave activity in the somatosensory cortex of anesthetized rats.

Rhythmic slow waves characterize brain electrical activity during natural deep sleep and under anesthesia, reflecting the synchronous membrane potential fluctuations of neurons in the thalamocortical network. Strong evidence indicates that the neocortex plays an important role in the generation of slow wave activity (SWA), however, contributions of individual cortical layers to the SWA generation are still unclear. The anatomically correct laminar profiles of SWA were revealed under ketamine/xylazine anesthesia, with combined local field potential recordings, multiple-unit activity (MUA), current source density (CSD) and time-frequency analyses precisely co-registered with histology. The up-state related negative field potential wave showed the largest amplitude in layer IV, the CSD was largest in layers I and III, while MUA was maximal in layer V, suggesting spatially dissociated firing and synaptic/transmembrane processes in the rat somatosensory cortex. Up-state related firing could start in virtually any layers (III-VI) of the cortex, but were most frequently initiated in layer V. However, in a subset of experiments, layer IV was considerably active in initiating up-state related MUA even in the absence of somatosensory stimulation. Somatosensory stimulation further strengthened up-state initiation in layer IV. Our results confirm that cortical layer V firing may have a major contribution to the up-state generation of ketamine/xylazine-induced SWA, however, thalamic influence through the thalamorecipient layer IV can also play an initiating role, even in the absence of sensory stimulation. This article is protected by copyright. All rights reserved

Kontextualizált névelem-felismerés és relációkinyerés kórházi zárójelentésekben

Cikkünkben a kórházi zárójelentések szövegbányászati feldolgozásával foglalkozó i2b2 szervezet 2010-es, információkinyeréssel kapcsolatos feladatára (Fourth i2b2/VA Shared-Task) készített megoldásunkat ismertetjük. Az első, névelem-felismerési feladatban három entitástípus szövegbeli előfordulásait, pontosabban egy szűk bennfoglaló nyelvtani egységet kellett megjelölni. A második, állításosztályozási feladatban ezen entitások említésének jellegét (kijelentő, tagadó, spekulatív stb.) kellett osztályozni. Végül a harmadik, relációkinyerési feladatban az egy mondatban szereplő entitások között fennálló kapcsolat meglétét és pozitív esetben a típusát kellett megállapítani. Megoldásainkban kontextusra épülő, a rendelkezésünkre bocsátott tanítóadaton betanított – részben szabályalapú, részben felügyelt gépi tanuláson alapuló – módszereket alkalmaztunk. Munkánkban elemezzük az egyes eljárások hatékonyságát és megvizsgálunk néhány lehetséges továbbfejlesztési irányt

Magyar szóalak- és morfológiaielemzés-adatbázis

Célunk egy olyan morfológiai elemz megoldás létrehozása, mely átlagos felhasználás mellett a szavak nagy arányát tudja elemezni, megengedve a helytelen szavak „közeli” értelmezését is. Ennek a megoldásnak mszakilag platformfüggetlennek és kevés szó elemzése esetén is hatékonynak kell lennie. Ennek érdekében egy olyan statikus MySQL adatbázist építünk, mely tartalmazza a szóalakokat és azok elemzését, így a szavak elemzése adatbázislekérdezéssel történhet. Kell feltöltöttséggel ez az adatbázis megvalósíthatja célunkat

A rescued dataset of sub-daily meteorological observations for Europe and the southern Mediterranean region, 1877–2012

Sub-daily meteorological observations are needed for input to and assessment of high-resolution reanalysis products to improve understanding of weather and climate variability. While there are millions of such weather observations that have been collected by various organisations, many are yet to be transcribed into a useable format. Under the auspices of the Uncertainties in Ensembles of Regional ReAnalyses (UERRA) project, we describe the compilation and development of a digital dataset of 8.8 million meteorological observations of essential climate variables (ECVs) rescued across the European and southern Mediterranean region. By presenting the entire chain of data preparation, from the identification of regions lacking in digitised sub-daily data and the location of original sources, through the digitisation of the observations to the quality control procedures applied, we provide a rescued dataset that is as traceable as possible for use by the research community. Data from 127 stations and of 15 climate variables in the northern African and European sectors have been prepared for the period 1877 to 2012. Quality control of the data using a two-step semi-automatic statistical approach identified 3.5 % of observations that required correction or removal, on par with previous data rescue efforts. In addition to providing a new sub-daily meteorological dataset for the research community, our experience in the development of this sub-daily dataset gives us an opportunity to share some suggestions for future data rescue projects. All versions of the dataset, from the raw digitised data to data that have been quality controlled and converted to standard units, are available on PANGAEA: https://doi.org/10.1594/PANGAEA.886511 (Ashcroft et al., 2018)

Ismert névelemek felismerése és morfológiai annotálása szabad szövegben

A szavak hálójában” projekt 61 keretében készülő internetes kereső- szolgáltatásnak egyik célja az, hogy lehet�séget nyújtson természetes nyelv magyar kérdésekkel internetes adatbázisok tartalmában az ún. mélyhálóban való keresésre. Az adatbázisokból ki lehet nyerni azokat az egyedi azonosítókat, amelyek együttese lehetővé teszi, hogy a felhasználói keresések információigénye és a mélyhálós tartalmak között kapcsolatot teremtsünk. Az egyedi azonosítókat névelemnek nevezzük. A természetes nyelv kérdések feldolgozásának kiemelt fontosságú része a bennük szereplő ismert névelemek felismerése, valamint a kérdésben betöltött szerepük meghatározásához a felismert névelemek morfológiai jegyeinek meghatározása. Cikkünkben bemutatjuk a probléma megoldására javasolt és megvalósított algoritmusunkat, amely számítási igényt tekintve is hatékonyan oldja meg a felvázolt feladatokat

Magyar nyelvű kérdő mondat elemző szoftver

Cikkünkben „A szavak hálójában” projekt keretében megvalósított kérdő mondatok elemzését végző programot ismertetjük. A projekt egyik célja egy olyan keresőszolgáltatás algoritmikus és architekturális feltételeinek megteremtése, amely lehetővé teszi, hogy természetes nyelv magyar kérdésekkel internetes adatbázisok tartalmában az ún. mélyhálóban keressünk. Ezen cél elérésének egyik fontos része a kérdő mondatok szintaktikai és szemantikai feldolgozása. A bemutatott szoftver a nyelvtani szerkezetek felismerésén kívül minta- és szótáralapú névelem-detektáló feladatokat is elvégez, amelynek nagy jelentősége van a kérdéselemzés következő lépése, a kontextusfelismerés során

Large-scale recording of thalamocortical circuits: in vivo electrophysiology with the two-dimensional electronic depth control silicon probe.

Recording simultaneous activity of a large number of neurons in distributed neuronal networks is crucial to understand higher order brain functions. Here, we demonstrate the in vivo performance of a recently developed electrophysiological recording system comprising a two-dimensional, multi-shank, high-density silicon probe with integrated CMOS electronics. The system implements the concept of electronic depth control (EDC), which enables the electronic selection of a limited number of recording sites on each of the probe shafts. This innovative feature of the system permits simultaneous recording of local field potentials (LFP), and single- and multiple-unit activities (SUA and MUA, respectively) from multiple brain sites with high quality and without the actual physical movement of the probe. To evaluate the in vivo recording capabilities of the EDC probe, we recorded LFP, MUA and SUA in acute experiments from cortical and thalamic brain areas of anesthetized rats and mice. The advantages of large-scale recording with the EDC probe are illustrated by investigating the spatiotemporal dynamics of pharmacologically induced thalamocortical slow wave activity in rats, by comparing the firing and burst properties of neurons located in various thalamic nuclei and by the two-dimensional tonotopic mapping of the auditory thalamus. In mice, spatial distribution of thalamic responses to optogenetic stimulation of the neocortex was examined. Utilizing the benefits of the EDC system may result in a higher yield of useful data from a single experiment compared to traditional passive multielectrode arrays, and thus in the reduction of animals needed for a research study

Winter Bird Assemblages in Rural and Urban Environments: A National Survey

Urban development has a marked effect on the ecological and behavioural traits of many living organisms, including birds. In this paper, we analysed differences in the numbers of wintering birds between rural and urban areas in Poland. We also analysed species richness and abundance in relation to longitude, latitude, human population size, and landscape structure. All these parameters were analysed using modern statistical techniques incorporating species detectability. We counted birds in 156 squares (0.25 km2 each) in December 2012 and again in January 2013 in locations in and around 26 urban areas across Poland (in each urban area we surveyed 3 squares and 3 squares in nearby rural areas). The influence of twelve potential environmental variables on species abundance and richness was assessed with Generalized Linear Mixed Models, Principal Components and Detrended Correspondence Analyses. Totals of 72 bird species and 89,710 individual birds were recorded in this study. On average (±SE) 13.3 ± 0.3 species and 288 ± 14 individuals were recorded in each square in each survey. A formal comparison of rural and urban areas revealed that 27 species had a significant preference; 17 to rural areas and 10 to urban areas. Moreover, overall abundance in urban areas was more than double that of rural areas. There was almost a complete separation of rural and urban bird communities. Significantly more birds and more bird species were recorded in January compared to December. We conclude that differences between rural and urban areas in terms of winter conditions and the availability of resources are reflected in different bird communities in the two environments