Search results for "Expo"
showing 10 items of 2430 documents
KOSMOS 2018 Gran Canaria mesocosm study: particle flux data from sediment trap
2021
The data set compiles sinking flux data collected during a KOSMOS mesocosm experiment carried out in the frame work of the Ocean Artificial Upwelling project. The experiment was performed in the North-East Atlantic Ocean off the coast of Gran Canaria in autumn 2018 and lasted for 39 days. In this study we investigated the effect of different intensities of artificial upwelling combined with two upwelling modes (recurring additions versus one singular addition) on POC export and its potential transfer efficiency to depth. The data set includes the amounts of surface water that were exchanged with nutrient-rich deep water (from ~300 m depth). It also contains particle flux data, i.e. POC flux…
In vivo ozone exposure does not increase DNA single-strand breaks in human peripheral lymphocytes
2013
In this randomized parallel study, we examined whether an acute ozone (O3) exposure leads to increased DNA strand breaks in human lymphocytes. The groups were exposed to 0.21 ppm O3 or filtered air for two hours. 30min and 4.5 h after exposure, DNA damage was determined in isolated lymphocytes using the Fast Micromethod. There was no detectable effect after O3 exposure. We conclude that an acute O3 exposure at the tested concentration does not lead to persistent DNA damage.
Growth phase-dependent regulation of nuoA-N expression in Escherichia coli K-12 by the Fis protein: upstream binding sites and bioenergetic significa…
2000
The expression of the nuoA-N operon of Escherichia coli K-12, which encodes the proton-pumping NADH dehydrogenase I is modulated by growth phase-dependent regulation. Under respiratory growth conditions, expression was stimulated in early exponential, and to a lesser extent in late exponential and stationary growth phases. The stimulation in the early exponential growth phase was not observed in fis mutants, which are deficient for the growth phase-responsive regulator Fis. Neither the alternative sigma factor RpoS nor the integration host factor (IHF) are involved in growth phase-dependent regulation of this operon. When incubated with nuo promoter DNA, isolated Fis protein formed three re…
What is the best fitting function? Evaluation of lactate curves with common methods from the literature
2015
Using the lactate threshold for training prescription is the gold-standard, although there are several open questions. One open question is: What is the best fitting method for the load-lactate data points? This investigation re-analyses over 3500 lactate diagnostic datasets in swimming. Our evaluation software examines six different fitting methods with two different minimization criteria (RMSE and SE). Optimization of parameters of the functions is put in excecution with gradient descent. From a mathematical point of view, the double phase model, which consists of two linear regression lines, shows the least errors (RMSE min 0.254 ± 0.172; SE min 0.311 ± 0.210). However, this method canno…
Etude numérique d'équations aux dérivées partielles non linéaires et dispersives
2011
Numerical analysis becomes a powerful resource in the study of partial differential equations (PDEs), allowing to illustrate existing theorems and find conjectures. By using sophisticated methods, questions which seem inaccessible before, like rapid oscillations or blow-up of solutions can be addressed in an approached way. Rapid oscillations in solutions are observed in dispersive PDEs without dissipation where solutions of the corresponding PDEs without dispersion present shocks. To solve numerically these oscillations, the use of efficient methods without using artificial numerical dissipation is necessary, in particular in the study of PDEs in some dimensions, done in this work. As stud…
A fuzzy decision support tool for demand forecasting
2007
In this paper we present a decision support forecasting system to work with univariate time series based on the generalized exponential smoothing (Holt-Winters) approach. It is conceived as an integrated tool which has been implemented in Visual Basic. For improving the accuracy of the automatic forecasting it uses an optimization-based scheme which unifies the stages of estimation of the parameters and selects the best method using a fuzzy multicriteria approach. The elements of the set of local minima of the non-linear programming problems allow us to build the membership functions of the conflicting objectives. A set of real data is analyzed to show the performance of our forecasting too…
Overdiagnosis and overimaging: an ethical issue for radiological protection
2019
Aims and objectives: This study aimed to analyse the key factors that influence the overimaging using X-ray such as self-referral, defensive medicine and duplicate imaging studies and to emphasize the ethical problem that derives from it. Materials and methods: In this study, we focused on the more frequent sources of overdiagnosis such as the total-body CT, proposed in the form of screening in both public and private sector, the choice of the most sensitive test for each pathology such as pulmonary embolism, ultrasound investigations mostly of the thyroid and of the prostate and MR examinations, especially of the musculoskeletal system. Results: The direct follow of overdiagnosis and overi…
GLOBAL DELAY TIME FOR GENERAL DISTRIBUTED NETWORKS WITH APPLICATIONS TO TIMING ANALYSIS OF DIGITAL MOS INTEGRATED CIRCUITS
1989
We consider here a general nerwork composed by n‐distributed parameters lines (with telegraph‐equations models) and m‐capacitors, all connected by a resistive multiport. An asymptotic stability property drives us to define and evaluate a global parameter (“λ‐delay time”) which describes the speed of signals propagation through the network. Because of its simplicity of calculation and its tightness, the given upper bound of the λ‐delay time is useful in timing analysis of MOS integrated chips.
Aerosol optical properties and instantaneous radiative forcing based on high temporospatial resolution CARSNET ground-based measurements over eastern…
2017
Abstract. Variations in the optical properties of aerosols and their radiative forcing were investigated based on long-term synchronous observations made at three-minute intervals from 2011 to 2015 over seven adjacent CARSNET (China Aerosol Remote Sensing NETwork) urban (Hangzhou), suburban (Xiaoshan, Fuyang, LinAn, Tonglu, Jiande) and rural (ChunAn) stations in the Yangtze River Delta region, eastern China. The aerosol optical depth (AOD) varied from 0.68 to 0.76, with two peaks in June and September, and decreased from the eastern coast to western inland areas. The ratio of the AOD of fine-mode particles to the total AOD was > 0.90 and the extinction Angström exponent was > 1.20 thr…
High-field nuclear spin relaxation in liquids and solids
1990
The authors generalise the standard theory of nuclear spin relaxation to situations in which the Markovian approximation is not applicable. Expressions for generalised frequency-dependent spin relaxation functions are presented. They show that under high-field conditions the relaxation of longitudinal magnetisation is exponential independent of the particular time dependence of the correlation functions.