A note on the factorization method of Niederreiter

AbstractIn this paper, we explicitly obtain the coefficient matrix arising from a linearization of Niederreiter's factorization algorithm and analyze the complexity of setting it up. It turns out that its setup cost is linear both in the degree of a polynomial to be factored and in the size of the base field

Origin of multi-level switching and telegraphic noise in organic nanocomposite memory devices.

The origin of negative differential resistance (NDR) and its derivative intermediate resistive states (IRSs) of nanocomposite memory systems have not been clearly analyzed for the past decade. To address this issue, we investigate the current fluctuations of organic nanocomposite memory devices with NDR and the IRSs under various temperature conditions. The 1/f noise scaling behaviors at various temperature conditions in the IRSs and telegraphic noise in NDR indicate the localized current pathways in the organic nanocomposite layers for each IRS. The clearly observed telegraphic noise with a long characteristic time in NDR at low temperature indicates that the localized current pathways for the IRSs are attributed to trapping/de-trapping at the deep trap levels in NDR. This study will be useful for the development and tuning of multi-bit storable organic nanocomposite memory device systems

Evolution of weighted scale-free networks in empirical data

Weighted scale-free networks exhibit two types of degree-strength relationship: linear and nonlinear relationships between them. To understand the mechanism underlying such empirical relationships, theoretical evolution models for weighted scale-free networks have been introduced for each case. However, those models have not yet been tested with empirical data. In this study, we collect temporal records of several online bulletin board systems and a movie actor network. We measure the growth rates of degree and strength of each vertex and weight of each edge within the framework of preferential attachment (PA). We also measure the probability of creating new edges between unconnected pairs of vertices. Then, based on the measured rates, linear and nonlinear growth models are constructed. We find that indeed the dynamics of creating new edges and adding weight to existing edges in a nonlocal manner is essential to reproduce the nonlinear degree-strength relationship. We also find that the degree-driven PA rule is more appropriate to real systems rather than the strength-driven one used for the linear model

Influence of rainfall events on zooplankton community characteristics and feeding habits in estuarine–coastal environments

In temperate estuaries, rainfall causes environmental fluctuations, such as salinity and suspended particulate matter (SPM), and can affect zooplankton distribution patterns. This study focused on the effect of temporary freshwater inflow on the composition of major zooplankton species and changes in their ecological status in the Seomjin River estuary before (June) and after (August) rainfall in 2018. Environmental data were collected from 14 and 15 stations before and after rainfall, respectively. All factors except for chlorophyll-a (Chl-a) concentration differed significantly before and after rainfall (p<0.05), and a salinity gradient extended to Yeosu Bay from Gwangyang Bay. Zooplankton abundance decreased significantly after rainfall. There was a high correlation between indicator species abundance and environmental factors after rainfall (correlation coefficient: 0.7521); however, the indicator species and environmental factors did not exhibit a significant correlation with salinity before rainfall. In terms of feeding habit composition, the carnivore proportion showed a significant decrease after rainfall compared to before rainfall (p<0.001), while the particle feeder proportion showed a significant increase after rainfall compared to before (p<0.001). In particular, Corycaeus spp. contributed significantly to the decrease in carnivore abundance after rainfall. Among the particle feeders, Copepodites significantly increased in abundance after rainfall. Carnivore abundance was negatively correlated with salinity, and particle feeder abundance was positively correlated with potential prey sources (SPM and Chl-a concentration), suggesting that particle feeders respond to the food-rich environment after rainfall

Are better conducting molecules more rigid?

We investigate the electronic origin of the bending stiffness of conducting molecules. It is found that the bending stiffness associated with electronic motion, which we refer to as electro-stiffness, $\kappa_{e}$, is governed by the molecular orbital overlap $t$ and the gap width $u$ between HOMO and LUMO levels, and behaves as $\kappa_{e}\sim t^{2}/\sqrt{u^2+t^{2}}$. To study the effect of doping, we analyze the electron filling-fraction dependence on $\kappa_{e}$ and show that doped molecules are more flexible. In addition, to estimate the contribution of $\kappa_{e}$ to the total stiffness, we consider molecules under a voltage bias, and study the length contraction ratio as a function of the voltage. The molecules are shown to be contracted or dilated, with $\kappa_{e}$ increasing nonlinearly with the applied bias

Conjugative plasmid mediated inducible nickel resistance in Hafnia alvei 5-5

Hafnia alvei 5-5, isolated from a soil-litter mixture underneath the canopy of the nickel-hyperaccumulating tree Sebertia acuminata (Sapotaceae) in New Caledonia, was found to be resistant to 30 mM Ni2+ or 2 mM Co2+. The 70-kb plasmid, pEJH 501, was transferred by conjugation to Escherichia coli, Serratia marcescens, and Klebsiella oxytoca. Transconjugant strains expressed inducible nickel resistance to between 5 and 17 mM Ni2+, and cobalt resistance to 2 mM Co2+. A 4.8-kb Sal–EcoRI fragment containing the nickel resistance determinant was subcloned, and the hybrid plasmid was found to confer a moderate level of resistance to nickel (7 mM Ni2+) even to E. coli. The expression of nickel resistance was inducible by exposure to nickel chloride at a concentration as low as 0.5 mM Ni2+. By random TnphoA´-1 insertion mutagenesis, the fragment was shown to have structural genes as well as regulatory regions for nickel resistance. Southern hybridization studies showed that the nickel-resistance determinant from pEJH501 of H. alvei 5-5 was homologous to that of pTOM9 from Alcaligenes xylosoxydans 31A