Pricing Strategies for User-Provided Connectivity Services

User-provided connectivity (UPC) services offer a possible alternative, orcomplement, to existing infrastructure-based connectivity. A userallows other users to occasionally connect through its home base inexchange for reciprocation, or possibly compensation. This service modelexhibits strong positive and negative externalities. A large user basemakes the service more attractive, as it offers more connectivity options toroaming users, but it also implies a greater volume of (roaming) trafficpassing through a user\u27s home base, which can increase congestion. Theseinteractions make it difficult to predict the eventual success of such aservice offering, and in particular how to effectively price it. This paperinvestigates a two-price policy where the first price is an introductory price that expires onceservice adoption reaches a certain level. The paper uses a simplifiedanalytical model to investigate pricing strategies under this policy, and their sensitivity to changesin system parameters. The insight and practicalguidelines this yields are validated numerically under morerealistic conditions

The crosslink density of styrene butadiene rubber/nano copper oxide nanocomposites

Styrene butadiene rubber (SBR) is one of the most applicant rubbers in the world which could be used in the industrial usages and medical applications. In other some works, combination of styrene butadiene rubber with other rubbers could be used for composite and nanocomposites applications. In this paper, crosslink density of rubber based nanocomposites have been investigated by swelling test. Results showed that nano copper oxide nano copper oxide affect the crosslink density content of nanocomposites with presence of nano copper oxide. Moreover, extraction and swelling tests of nanocomposites has been carried out. The results showed that the nano copper oxide increased the amount of average molecular weight between two crosslinks

The low abundance of CpG in the SARS-CoV-2 genome is not an evolutionarily signature of ZAP

The zinc finger antiviral protein (ZAP) is known to restrict viral replication by binding to the CpG rich regions of viral RNA, and subsequently inducing viral RNA degradation. This enzyme has recently been shown to be capable of restricting SARS-CoV-2. These data have led to the hypothesis that the low abundance of CpG in the SARS-CoV-2 genome is due to an evolutionary pressure exerted by the host ZAP. To investigate this hypothesis, we performed a detailed analysis of many coronavirus sequences and ZAP RNA binding preference data. Our analyses showed neither evidence for an evolutionary pressure acting specifically on CpG dinucleotides, nor a link between the activity of ZAP and the low CpG abundance of the SARS-CoV-2 genome

(2E)-2-[(2-Hy­droxy-4-meth­oxy­phen­yl)(phen­yl)methyl­idene]-N-phenyl­hydrazinecarboxamide dimethyl­formamide monosolvate

The title compound, C21H19N3O3·C3H7NO, adopts an E conformation with respect to the azomethine bond and crystallizes in the amide form. The dihedral angle between the rings lined to the C=N bond is 88.60 (12)°. The dimethyl­formamide solvent mol­ecule is disordered over two orientations with site occupancies of 0.684 (3) and 0.316 (3). The two N atoms of the hydrazinecarboxamide group are involved in inter­molecular N—H⋯O hydrogen bonds in which the dimethyl­formamide O atom acts as acceptor. The structure also features π–π inter­actions, with a centroid–centroid distance of 3.6561 (13) Å. Classical and non-classical intra­molecular O—H⋯N and C—H⋯O hydrogen bonds are also present

Aquaculture code of conduct and mechanization management

In this report rules and focal points about code of conduct for cold water farm, warm water establishment, mechanization management and oxygen generators are collected and discussed. One of the most important point difference between aquaculture engineering with mechanization. Mechanization is improvement of management level from ancient to better by some special tools but aquaculture engineering can do by any vessel in every management

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types