1,721,017 research outputs found
Sequential ordered mechanism for the sodium-glutamate transport in intestinal brush border membrane vesicles
No full textAbstractThe glutamate/aspartate carrier localized in the brush-border membrane vesicles from enterocytes is known as a transport system catalyzing a sodium-substrate cotransport driven by the sodium gradient across the membrane. The kinetics of this transport system is studied by analogy with an enzymatic bi-substrate reaction. The results of this approach can be summarized as follows: (1) The dependence of the l-glutamate transport rate on the sodium concentration is sigmoidal, and the stoichiometry of the transport is 2 Na+/1 glutamate/1 carrier molecule. (2) The mechanism is sequential ordered, with l-glutamate binding after both the sodium cations. In addition, there is a very high degree of cooperativity between the two sodium binding sites
Neonatal seizures in preterm infants: A systematic review of mortality risk and neurological outcomes from studies in the 2000's
No full textIntroduction: Neonatal seizures (NS) are associated with increased mortality and risk of cerebral palsy, epilepsy and intellectual disability. We performed a systematic review with the primary objective to delineate the rate of these outcomes following NS in preterm infants from studies published in the 2000’s and the secondary objective to identify risk factors. Methods: Inclusion criteria: original articles published between 1/1/2000 and 12/31/2018, written in English, evaluating newborns ≤37 weeks of gestational age and suffering from NS, in which at least one of these was evaluated: epilepsy, cerebral palsy, intellectual disability/developmental delay, normal outcome, death. Results: Twenty-two papers were selected and all were observational, with a retrospective design in 15. Three were population-based and twenty-one have a comparison. It has been found a 22–80 % of mortality, 11.3–38.9 % of epilepsy, 12–84.6 % of cerebral palsy, and 20–42.7 % of intellectual disability/developmental delay rate. An increased risk for all outcomes considered was reported. Risk factors for specific outcomes were provided by a minority of studies. However, inclusion criteria, definition of NS and measured outcomes, follow-up lengths differed considerably between studies. Discussion: Results of the selected studies are only partially comparable or generalizable because of differences in study design. They have a risk for potential biases, although they provide (if analyzed) readily available prognostic factors, easy to apply in clinical practice. Prospective, population-based studies with EEG-defined NS are warranted in order to produce evidence-based guidance for management of preterm newborns with seizures
Effetto dei reagenti dell'arginina sul carrier mitocondriale del citrato parzialmente purificato e ricostituito nei liposomi
No full textInibizione del carrier mitocondriale del 2-chetoglutarato da parte dell'eosina-5-maleimide
No full textVerifica della congruenza geometrica tra le mappe di impianto catastali e l’attuale formato vettoriale
No full textIl recente processo d’informatizzazione del patrimonio cartografico catastale ha comportato, in alcuni casi, un decadimento della qualità geometrica delle mappe; infatti, agli errori già presenti sul supporto cartaceo, si sono aggiunte nuove deformazioni legate alle operazioni di scansione, georefenziazione e vettorializzazione degli originali d’impianto (OI).
In questo lavoro, prendendo in esame diversi fogli del comune di Eboli (SA), è stata verificata la congruenza geometrica tra le mappe d’impianto e quelle vettoriali attuali esportabili dal WEGIS (Web Enabled GIS) nel formato CXF (Cadastral eXchange Format).
Poiché il suddetto formato non è supportato dai principali software in commercio è stato implementato, in ambiente Java, un tool che consente di leggere i file CXF, di manipolare opportunamente le geometrie e le informazioni in esso contenute e, infine, di generare ed esportare i fogli di mappa in formato shapefile. Anche se esistono diversi software che effettuano tali operazioni, si è preferito svilupparne un nuovo in Java per costituire una base per una futura implementazione, delle funzionalità sopra descritte, in un servizio web fornito dall’application server WildFly (già noto come JBoss).
In una fase successiva, al fine di confrontare le mappe catastali attuali con quelle d’impianto (disponibili sotto forma di file raster non georiferiti), è stato necessario georiferire queste ultime. Tale operazione è stata ripetuta impiegando varie trasformazioni (lineare, polinomiale di secondo e di terzo grado) e, per ciascuna di esse, l’analisi dei residui ha consentito di stimarne la precisione.
Dopo ogni singolo processo di georeferenziazione è stato creato, per ogni raster, uno shapefile di alcune particelle distribuite in modo uniforme nel foglio d’impianto. Ponendo a confronto i due shapefile ottenuti, rispettivamente, dalla mappa vettoriale CXF e dalla relativa mappa d’impianto georiferita, è stato possibile valutare gli spostamenti, in direzione nord ed est, e le differenze areali, che le attuali particelle mostrano rispetto a quelle d’impianto.The recent informatization process of the cadastral cartographic heritage has resulted, in some cases, in a worsening of the geometric quality of maps; in fact, new distortions due to scanning, georeferencing and vectorization of the original maps have been added to the errors already inherent the map.
In this work, the geometric congruence between the original maps of establishment and the current vectorial maps exportable from the WEGIS (Web Enabled GIS) in CXF (Cadastral eXchange Format), has been verified by examining several sheets of the Eboli town (SA).
Since the above format is not supported by the main commercial software products, a Java tool has been implemented, that allows to read CXF files, manipulate appropriately the geometries and the information contained therein and, finally, generate and export the map sheets in shapefile format. Although there are several software that perform these operations, it was decided to develop a new in Java to provide a basis for future implementation, of the functionalities described above, in a web service provided by the application server WildFly (formerly known as JBoss).
At a later stage, the actual maps of establishment (available as non geo-referenced raster files) were georeferenced in order to be compared with the current cadastral maps. This operation was repeated by using various transformations (linear, second and third order polynomial) and, for each of them, the precision was estimated based on the residuals analysis.
After each georeferencing process, for each raster, a shapefile of some land parcels uniformly distributed in the original map was created. By comparing the two shapefiles obtained, respectively, from the CXF vector map and from the original georeferenced map, the shifts in the north and east directions, as well as, the differences of area between current and original land parcels were evaluated
Funzioni iperboliche della latitudine isometrica in termini delle funzioni circolari della latitudine geodetica
No full textIn questo articolo si deducono espressioni chiuse approssimate delle funzioni
iperboliche tangente ( u tanh ) e secante ( u cosh 1 ) della latitudine isometrica ellissoidica u in
termini delle funzioni circolari della latitudine geodetica φ e secondo le potenze pari dell’ eccen-
tricità fino al 12-mo grado. Le espressioni sono dedotte mostrando l’ uguaglianza delle suddette funzioni iperboliche di u con le funzioni circolari della latitudine conforme ellissoidica, ed inserendo negli sviluppi in serie di Taylor di queste ultime l’ espressione (Crocetto et al., 2009) della
differenza tra la latitudine conforme e la corrispondente latitudine geodetica. Si riportano esempi
numerici per verificare che l’ accuratezza delle espressioni sia spinta fino all’ ordine della doppia
precisione macchina eps con cui sono rappresentati ed elaborati i dati numerici in “Floating Point” nei moderni calcolatori elettronici dai vari linguaggi di programmazione e di calcolo. La forma polinomiale mista delle espressioni, oltre a risultare di contenuto costo computazionale,
renderà possibile, in un prossimo lavoro, le loro inversioni al fine di dedurre sviluppi chiusi ap-
prossimati ed accurati (fino alla doppia precisione eps) delle funzioni circolari di φ in termini di
funzioni iperboliche della corrispondente u ; tali inversioni ed ulteriori elaborazioni avranno co-
me obiettivo finale un nuovo metodo per il calcolo di coordinate cartografiche Gaussiane, con
adeguata accuratezza e per singoli fusi geografici di elevata ampiezza in longitudine
Uno sviluppo accurato della latitudine conforme in termini della latitudine geodetica
No full textIn questo articolo si deduce un’ espressione approssimata della latitudine
conforme ellissoidica in termini della corrispondente latitudine geodetica e delle potenze pari del-
la prima eccentricità con coefficienti polinomi trigonometrici della latitudine geodetica. Dall’ u-
guaglianza di due differenti sviluppi della latitudine isometrica opportunamente troncati, viene
ricavata dapprima per successive approssimazioni la differenza tra la latitudine conforme e la cor-
rispondente geodetica, ed infine l’ espressione approssimata della conforme. Per l’elevato grado
delle potenze dell’eccentricità (fino al 12-mo) e della funzione seno (fino all’ 11-mo) della latitu-
dine geodetica, l’ espressione risulta estremamente accurata, fino a conseguire un’ approssimazio-
ne dell’ ordine della (doppia) precisione macchina eps con cui sono rappresentati ed elaborati i
dati numerici in “Floating Point” nei moderni calcolatori elettronici dai vari linguaggi di program-
mazione e di calcolo. Si riportano esempi numerici di verifica dell’ accuratezza dell’ espressione.
L’ approssimazione, ottenibile con un minor costo computazionale rispetto ad altre espressioni ri-
portate in letteratura geodetica e cartografica, e la specifica forma di questo sviluppo della latitu-
dine conforme risultano necessarie per l’ applicazione che verrà mostrata in un prossimo articolo,
al fine ultimo di implementare un nuovo metodo di calcolo delle coordinate cartografiche Gaussiane per fusi di elevata ampiezza in longitudine e con adeguate accuratezze
A Matlab geodetic software for processing airborne LIDAR bathymetry data
Full text linkThe ability to build three-dimensional models through technologies based on satellite navigation systems GNSS and the continuous development of new sensors, as Airborne Laser Scanning Hydrography (ALH), data acquisition methods and 3D multi-resolution representations, have contributed significantly to the digital 3D documentation, mapping, preservation and representation of landscapes and heritage as well as to the growth of research in this fields. However, GNSS systems led to the use of the ellipsoidal height; to transform this height in orthometric is necessary to know a geoid undulation model. The latest and most accurate global geoid undulation model, available worldwide, is EGM2008 which has been publicly released by the U.S. National Geospatial-Intelligence Agency (NGA) EGM Development Team. Therefore, given the availability and accuracy of this geoid model, we can use it in geomatics applications that require the conversion of heights. Using this model, to correct the elevation of a point does not coincide with any node must interpolate elevation information of adjacent nodes. The purpose of this paper is produce a Matlab® geodetic software for processing airborne LIDAR bathymetry data. In particular we want to focus on the point clouds in ASPRS LAS format and convert the ellipsoidal height in orthometric. The algorithm, valid on the whole globe and operative for all UTM zones, allows the conversion of ellipsoidal heights using the EGM2008 model. Of this model we analyse the slopes which occur, in some critical areas, between the nodes of the undulations grid; we will focus our attention on the marine areas verifying the impact that the slopes have in the calculation of the orthometric height and, consequently, in the accuracy of the in the 3-D point clouds. This experiment will be carried out by analysing a LAS APRS file containing topographic and bathymetric data collected with LIDAR systems along the coasts of Oregon and Washington (USA)
Inhibition of the mitochondrial tricarboxylate carrier by arginine-specific reagents
No full textAbstractThe effect of arginine-specific reagents on the activity of the partially purified and reconstituted tricarboxylate carrier of the inner mitochondrial membrane has been studied. It has been found that 1,2-cyclohexanedione, 2,3-butanedione, phenylglyoxal and phenylglyoxal derivatives inhibit the reconstituted citrate/citrate exchange activity. The inhibitory potency of the phenylglyoxal derivatives increases with increasing hydrophilic character of the molecule. Citrate protects the tricarboxylate carrier against inactivation caused by the arginine-specific reagents. Other tricarboxylates, which are not substrates of the carrier, have no protective effect. The results indicate that at least one essential arginine residue is located at the substrate-binding site of the tricarboxylate carrier and that the vicinity of the essential arginine(s) has a hydrophilic character
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