Search results for "SIM"

Introduction

1990

Biografia / Antologia

2019

Aluminium nitrate ceramics: a potential UV dosemeter material.

2002

The ceramic material AlN-Y 2 O 3 is proposed as a potential ultraviolet radiation (UVR) dosemeter using optically stimulated luminescence (OSL) and thermally stimulated luminescence (TL). Experimental studies have shown that AlN ceramics exhibit attractive characteristics suitable for practical UV dosimetry applications. The features are: (1) the spectral sensitivity covers the 200-350 nm range, in the UV-B region it is similar to that of human skin; (2) the angular dependence of the incident radiation follows the cosine law; (3) high yields of both UVR-induced OSL and TL signals compared to those of Al 2 O 3 :C; and (4) a large dynamic range TL signal (5 orders of magnitude). Although ther…

Analysis of neuronal networks in the visual system of the cat using statistical signals--simple and complex cells. Part II.

1978

Superimposing additively a two-dimensional noise process to deterministic input signals (bars) the neurons of area 17 show a class-specific reaction for the task of signal extraction. Moving both parts of the signals simultaneously and varying the signal to noise ratio (S/N) the simple cells achieve the same performance as resulted from the psychophysical experiment. Type I complex cells extract moving deterministic signals (i.e. bars) from the stationary noise, whereas in the answers of Type II complex cells the statistical parts of the signals predominate. Considering the different cell types each as a series of a linear and a nonlinear system one obtains the cell specific space-time freq…

Cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus

1993

The pattern of expression of GFAP immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (SIV). Blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. Strong GFAP immunoreactivity was found in astrocytic cells in both uninfected and SIV-infected juvenile macaque in the subpial cerebral cortex and in subcortical white matter, where GFAP-positive cells were abundant. GFAP staining of cortical layers 2-6 on the other hand was weak or absent in three uninfected contro…

DNA barcoding reveals different cestode helminth species in northern European marine and freshwater ringed seals

2021

Three subspecies of the ringed seal (Pusa hispida) are found in northeastern Europe: P. h. botnica in the Baltic Sea, P. h saimensis in Lake Saimaa in Finland, and P. h. ladogensis in Lake Ladoga in Russia. We investigated the poorly-known cestode helminth communities of these closely related but ecologically divergent subspecies using COI barcode data. Our results show that, while cestodes from the Baltic Sea represent Schistocephalus solidus, all worms from the two lakes are identified as Ligula intestinalis, a species that has previously not been reported from seals. The observed shift in cestode communities appears to be driven by differential availability of intermediate fish host spec…

A Simulation Model of a Tandem Coordinated Supply Chain

2010

This paper presents a study of a coordinated production inventory-system. In the proposed model, any echelon considers its successors as part of its inventory system and generates the replenishment order on the basis of operational information of its partners. We show that the coordinated decision making allows elimination of information distortion along the chain. Furthermore, we show how the bottom-up transmission of inefficiencies, typical of traditional supply chains, is avoided.

Comparative computational analysis of different active site conformations and substrates in a chalcone isomerase catalyzed reaction.

2006

Chalcone isomerase catalyzes the transformation of chalcones to flavanones. We present a computational study of the rate-limiting chemical step, an intramolecular Michael addition of a 2'-oxyanion to the alpha,beta-double bound. By using quantum mechanical/molecular mechanical hybrid methods we traced the free-energy profiles associated with the reaction of two different substrates (chalcone and 6'-deoxychalcone) in two different conformations of the active site that are described in the different crystallographic structures available. We have obtained significant differences (about 4 kcal/mol) in the free-energy barriers calculated for the two active sites. According to our results, the ac…

Climate change impacts on phytosanitary risk evolution in north-eastern France vineyards : observations and modeling : The case of powdery mildew

2021

From now on, agriculture must adapt and anticipate climate change, whose impact has already been observed on the biology of crops and their production. Beyond plants, this climate change also impacts pathogen development and therefore host/pathogen interactions. Thus, building adaptation strategies requires considering not only the crops but also the organisms with which they interact.The objective of this thesis is to characterize the impact of climate change on the phytosanitary risk related to grapevine powdery mildew (Erysiphe necator) in the wine regions of Burgundy and Champagne. More particularly, it questions two central aspects related to the epidemic risk: the grapevine sensitive …

Channel aggregation with guard-band in D-OFDM based CRNs: Modeling and performance evaluation

2016

Channel aggregation (CA) techniques can offer flexible channel allocation and improve overall system performance in multi-channel cognitive radio networks (CRNs). Although many CA techniques have been proposed and studied, the impact of guard-band on CA for channel access has not been addressed in-depth. In this paper, we study the guard-band allocation mechanisms in discontinuous-orthogonal frequency division multiplexing (D-OFDM) based CRNs, and investigate the impact of guard-band sharing on SU flows when CA is enabled. Continuous time Markov chain (CTMC) based models have been developed in order to investigate the stochastic behavior of PU and SU flows. Based on our mathematical analysi…