The perturbed compound Poisson risk model with linear dividend barrier

AbstractIn this paper, we consider a diffusion perturbed classical compound Poisson risk model in the presence of a linear dividend barrier. Partial integro-differential equations for the moment generating function and the nth moment of the present value of all dividends until ruin are derived. Moreover, explicit solutions for the nth moment of the present value of dividend payments are obtained when the individual claim size distribution is exponential. We also provided some numerical examples to illustrate the applications of the explicit solutions. Finally we derive partial integro-differential equations with boundary conditions for the Gerber–Shiu function

The Gerber-Shiu Expected Penalty Function for the Risk Model with Dependence and a Constant Dividend Barrier

We consider a compound Poisson risk model with dependence and a constant dividend barrier. A dependence structure between the claim amount and the interclaim time is introduced through a Farlie-Gumbel-Morgenstern copula. An integrodifferential equation for the Gerber-Shiu discounted penalty function is derived. We also solve the integrodifferential equation and show that the solution is a linear combination of the Gerber-Shiu function with no barrier and the solution of an associated homogeneous integrodifferential equation

Some Similarity Measures of Neutrosophic Sets Based on the Euclidean Distance and Their Application in Medical Diagnosis

Similarity measure is an important tool in multiple criteria decision-making problems, which can be used to measure the difference between the alternatives. In this paper, some new similarity measures of single-valued neutrosophic sets (SVNSs) and interval-valued neutrosophic sets (IVNSs) are defined based on the Euclidean distance measure, respectively, and the proposed similarity measures satisfy the axiom of the similarity measure. Furthermore, we apply the proposed similarity measures to medical diagnosis decision problem; the numerical example is used to illustrate the feasibility and effectiveness of the proposed similarity measures of SVNSs and IVNSs, which are then compared to other existing similarity measures

Cybersecurity and safety analysis in online social networks

The research work deal with the security and safety issues related to the use of online social networks and it successfully presented AI-based solutions to address these issues in online social networks

Salmonella produce microRNA-like RNA fragment Sal-1 in the infected cells to facilitate intracellular survival.

Salmonella have developed a sophisticated machinery to evade immune clearance and promote survival in the infected cells. Previous studies were mostly focused on either bacteria itself or host cells, the interaction mechanism of host-pathogen awaits further exploration. In the present study, we show that Salmonella can exploit mammalian cell non-classical microRNA processing machinery to further process bacterial small non-coding RNAs into microRNA-like fragments. Sal-1, one such fragment with the highest copy number in the infected cells, is derived from Salmonella 5-leader of the ribosomal RNA transcript and has a stem structure-containing precursor. Processing of Sal-1 precursors to mature Sal-1 is dependent on host cell Argonaute 2 (AGO2) but not Dicer. Functionally, depleting cellular Sal-1 strongly renders the Salmonella bacteria less resistant to the host defenses both in vitro and in vivo. In conclusion, we demonstrate a novel strategy for Salmonella evading the host immune clearance, in which Salmonella produce microRNA-like functional RNA fragments to establish a microenvironment facilitating bacterial survival

Comparative Genomics of Bacillus thuringiensis Reveals a Path to Specialized Exploitation of Multiple Invertebrate Hosts

This is the final version of the article. Available from American Society for Microbiology via the DOI in this record.Understanding the genetic basis of host shifts is a key genomic question for pathogen and parasite biology. The Bacillus cereus group, which encompasses Bacillus thuringiensis and Bacillus anthracis, contains pathogens that can infect insects, nematodes, and vertebrates. Since the target range of the essential virulence factors (Cry toxins) and many isolates is well known, this group presents a powerful system for investigating how pathogens can diversify and adapt to phylogenetically distant hosts. Specialization to exploit insects occurs at the level of the major clade and is associated with substantial changes in the core genome, and host switching between insect orders has occurred repeatedly within subclades. The transfer of plasmids with linked cry genes may account for much of the adaptation to particular insect orders, and network analysis implies that host specialization has produced strong associations between key toxin genes with similar targets. Analysis of the distribution of plasmid minireplicons shows that plasmids with orf156 and orf157, which carry genes encoding toxins against Lepidoptera or Diptera, were contained only by B. thuringiensis in the specialized insect clade (clade 2), indicating that tight genome/plasmid associations have been important in adaptation to invertebrate hosts. Moreover, the accumulation of multiple virulence factors on transposable elements suggests that cotransfer of diverse virulence factors is advantageous in terms of expanding the insecticidal spectrum, overcoming insect resistance, or through gains in pathogenicity via synergistic interactions between toxins.IMPORTANCE Population genomics have provided many new insights into the formation, evolution, and dynamics of bacterial pathogens of humans and other higher animals, but these pathogens usually have very narrow host ranges. As a pathogen of insects and nematodes, Bacillus thuringiensis, which produces toxins showing toxicity to many orders of insects and other invertebrates, can be used as a model to study the evolution of pathogens with wide host ranges. Phylogenomic analysis revealed that host specialization and switching occur at the level of the major clade and subclade, respectively. A toxin gene co-occurrence network indicates that multiple toxins with similar targets were accumulated by the same cell in the whole species. This accumulation may be one of the strategies that B. thuringiensis has used to fight against host resistance. This kind of formation and evolution of pathogens represents a different path used against multiple invertebrate hosts from that used against higher animals.This work was supported by the National Key Research and Development Program of China (2017YFD0201201), the China 948 Program of the Ministry of Agriculture (2016-X21), the National Natural Science Foundation of China (NSFC) (31500003 and 31670085), the China Postdoctoral Science Foundation-funded project (2015M580649 and 2016T90700), and Chinese Fundamental Research Funds for the Central Universities (2662016QD039, 2662015PY123, and 2662017PY094)

Production of distilled spirits using grain sorghum through liquid fermentation

The objectives of this research were to investigate the fermentation performance of US sorghum varieties for the production of distilled spirits as well as their associated coproducts and to study the formation of volatile compounds that are related to the flavor quality of the spirits. Three US sorghum varieties (red, white, and waxy sorghums) and four yeast strains (DADY, Ethanol Red, GR-2, and 71B) were used for distilled spirit production. Both sorghum variety and type of yeast strains had effects on alcohol concentration and alcohol yield. The alcohol concentration varied from 10.26 to 11.34% (v/v) while alcohol yield varied from 80.93 to 90.33%. Using Ethanol Red yeast achieved consistently the highest average alcohol concentration (11.10%, v/v) and yield (87.33%) regardless of variation in sorghum variety. Waxy sorghum demonstrated significantly higher average alcohol concentration (11.20%, v/v) and yield (89.65%) than white sorghum (10.74% for concentration and 84.7% for yield) and red sorghum (10.28% for concentration and 82.27% for yield). Alcohol fermentation also produces other metabolites as byproducts. Glycerol and lactic acid are the two major byproducts found from sorghum spirit fermentation. DADY produced the highest level of glycerol (∼1.4–1.5%, v/v) during fermentation, while GR-2 produced the lowest level of glycerol (0.9–1.1%, v/v). For all conditions, the lactic acid level was less than 1.2% (v/v). Eight volatile compounds were identified in sorghum spirits which mainly relate to fruity, sour, sweet, floral, buttery, and creamy flavors of the spirits

Pokemon GO in Melbourne CBD: A case study of the cyber-physical symbiotic social networks

[EN] The recent popular game, Pokemon GO, created two symbiotic social networks by location-based mobile augmented reality (LMAR) technique. One is in the physical world among players, and another one is in the cyber world among players' avatars. To date, there is no study that has explored the formation of each social network and their symbiosis. In this paper, we carried out a data-driven research on the Pokemon GO game to solve this problem. We accordingly organised the collection of two real datasets. For the first dataset, we designed a questionnaire to collect players' individual behaviours in Pokemon GO, and used maps of Melbourne (Australia) to track and record their usual playing areas. Based on the data that we collected, we modelled the formation of the symbiotic social networks in both physical world (i.e. for players) and cyber world (i.e. for avatars) as well as interactions between players and Pokemon GO elements (i.e. 'bridges' of the two worlds). By investigating the mechanism of network formation, we revealed the relatively weak correlation between the formation processes of the two networks. We further incorporated the real-world pedestrian dataset collected by sensors across Melbourne CBD into the study of their symbiosis. Based on the second dataset, we examined the changes of people's social behaviours in terms of most visited places. The results suggested that the existence of the cyber social network has reciprocally changed the structure of the symbiotic physical social network. (C) 2017 Elsevier B.V. All rights reserved.This research is partially supported by the Australian Research Council projects DP150103732, DP140103649, and LP140100816. The authors extend their appreciation to the International Scientific Partnership Program (ISPP) at King Saud University, Riyadh, Saudi Arabia for funding this work through the project No. ISPP#0069.Wang, D.; Wu, T.; Wen, S.; Liu, D.; Xiang, Y.; Zhou, W.; Hassan Mohamed, H.... (2018). Pokemon GO in Melbourne CBD: A case study of the cyber-physical symbiotic social networks. Journal of Computational Science. 26:456-467. https://doi.org/10.1016/j.jocs.2017.06.009S4564672

An Evaluation of the Mellor-Yamada-Janjić Formulation Parameters for the QNSE Scheme in the WRF Model over the Lower Yangtze River Valley

Accurate description of boundary layer processes is important for numerical simulations, and some model parameters in the boundary layer schemes play an important role in the model simulations. The Quasi-Normal Scale Elimination (QNSE) scheme in the Weather Research and Forecasting (WRF) model version 3.1.1 reverts into the Mellor-Yamada-Janjić (MYJ) model under unstable and neutral conditions. The parameters (A1, A2, B1, B2, C1) that affect the turbulent mixing in the MYJ formulation are the proportional coefficients of turbulence length scales and the master turbulence length scale. This study examines the model simulations sensitivity to different MYJ parameters. The simulation results show that MYJ parameters play a significant role in rainfall simulations. The analysis results imply that the parameters may affect the rainfall mainly by changing turbulent mixing and coupling with other physical process, such as cumulus convection processes, and then changing heat, momentum, and moisture transfer. The previous parameters used in the original MYJ formulation are not always the best and none of the parameters are always the best. It may be more appropriate that the parameters should be adopted in their plausible physical bounds depending on the planetary boundary layer (PBL) structures characteristics under specific meteorological and geographical circumstances