Uniqueness of Rankin-Selberg periods

Let $k$ be a local field of characteristic zero. Rankin-Selberg's local zeta integrals produce linear functionals on generic irreducible admissible smooth representations of $GL_n(k)\times GL_r(k)$, with certain invariance properties. We show that up to scalar multiplication, these linear functionals are determined by the invariance properties

Novel Swine Influenza Virus Reassortants in Pigs, China

During swine influenza virus surveillance in pigs in China during 2006–2009, we isolated subtypes H1N1, H1N2, and H3N2 and found novel reassortment between contemporary swine and avian panzootic viruses. These reassortment events raise concern about generation of novel viruses in pigs, which could have pandemic potential

Assessing the application of miscible CO2 flooding in oil reservoirs: a case study from Pakistan

Miscible carbon dioxide (CO2) flooding has been recognized as a promising approach to enhance the recovery of oil reservoirs. However, depending on the injection strategy and rock/fluid characteristics, efficiency of the miscible CO2flooding varies from reservoir to reservoir. Although, many studies have been carried out to evaluate the performance of the miscible CO2flooding, a specific strategy which can be strictly followed for a hydrocarbon reservoir has not been established yet. The aim of this study is to assess one of Pakistan’s oil reservoirs for miscible CO2flooding by applying a modified screening criterion and numerical modeling. As such, the most recent miscible CO2screening criteria were modified, and a numerical modeling was applied on the prospective reservoir. Based on the results obtained, South oil reservoir (S3) is chosen for a detailed assessment of miscible CO2flooding. It was also found that implementation of CO2water-alternating gas (CO2-WAG) injection at early stages of production can increase the production life of the reservoir

Significant Differences in Intestinal Microbial Communities in Aquatic Animals from an Aquaculture Area

While much attention has been given to the role of animal intestinal microbes, few studies have focused on microbial communities and associated functions in cultured aquatic animals. In this study, high–throughput sequencing was used to analyze intestinal microbial communities and functions in fish, shrimp, crab and razor clams. Alpha diversity analyses showed significant differences in intestinal microbial diversity amongst these aquatic animals, and that shrimp intestines harbored the highest diversity and species numbers. T–test analyses (p < 0.05) showed significant differences in dominant microbial operational taxonomic units (OTUs) between all aquatic animals. Predominant intestinal bacteria included; Gammaproteobacteria, Fusobacteria, Mollicutes, Spirochaetia, Cyanobacteria, Bacteroidia and Bacilli. Similarly, anaerobic bacteria were highly diverse in animal intestines and included; Vibrio, Photobacterium, Cetobacterium, Propionigenium, Candidatus Hepatoplasma, Paraclostridium, and Lactobacillus. Principal co–ordinate analysis indicated that the distribution characteristics of intestinal microbes varied with animal species; in particular, we observed a high variability among shrimp intestinal samples. This variability indicated these genera had suitability for the different intestinal environment. Function prediction analysis indicated significant differences amongst different animals in the major functional groups, and that microbial functional profiles were strongly shaped by the intestinal environment. Thus, this study provides an important reference for future studies investigating crosstalk between aquatic animal hosts and their intestinal microbiota

Direct numerical simulation of impinging shock wave and turbulent boundary layer interaction over a wavy-wall

The interaction of an impinging oblique shock wave with an angle of 30? and a super-sonic turbulent boundary layer at Ma1=2.9 and Reh = 2400 over a wavy-wall is investigated through direct numerical simulation and compared with the interaction on a flat-plate under the same flow conditions. A sinusoidal wave with amplitude to wavelength ratio of 0.26 moves in the streamwise direction and is uniformly distributed across the spanwise direction. The influences of the wavy-wall on the interaction, including the characterization of the flow field, the skin-friction, pressure and the budget of turbulence kinetic energy, are systematically studied. The region of sep-aration grows slightly and decomposes into four bubbles. Local peaks of skin-friction are observed at the rear part of the interaction region. The low-frequency shock motion can be seen in the wall pressure spectra. Analyses of the turbulence kinetic energy budget indicate that both diffusion and transport significantly increase near the crests, balanced by an amplified dissipation in the near-wall region. Proper orthogonal decomposition analyses show that the most energetic structures are asso-ciated with the separated shock and the shear layer over the bubbles. Only the bubbles in the first two troughs are dominated by a low-frequency enlargement or shrinkage. ? 2021 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Superscript/Subscript Available</commen

Abundance and Diversity of Several Bacterial Genera in the Mariculture Environment

Although there have been some studies on pathogenic bacteria and their pathogenicity in animals, few studies have assessed the effects of aquaculture on the diversity of potentially pathogenic bacteria. This study used Illumina sequencing and quantitative PCR to explore the diversity of several bacterial genera containing pathogenic bacteria in the mariculture environment and the intestines of different cultured animals. These bacterial genera can be divided into two categories: The first category (14 genera) had high abundances and a low coefficient of variation among similar samples were significantly correlated with the total number of bacteria (r2 > 0.7, p ≈ 0). The other category (7 genera) with low abundances and a high coefficient of variation had no significant relationship with bacterial abundance. These results indicated that these bacterial genera had different responses and adaptation mechanisms to the aquaculture environment. Principal component analysis (PCA) showed that a high abundance of genera was closely related to the pond environment. The abundance of these bacterial genera in the animals’ intestines was much higher than source water, especially for Mycoplasma, Pseudoalteromonas, Vibrio, and Enterococcus, suggesting the aquaculture promoted the high abundance of these bacteria. This study provides a theoretical basis for sediment-associated pathogens acting as a potential pathogen source in the aquaculture environment. This study provides a strategy for disease prevention and control according to the characteristics of potential pathogens in the cultural process

Wall-shear stress fluctuations in a supersonic turbulent boundary layer over an expansion corner

The effect of wall expansion on the structural and statistical characteristics of wall-shear stress (WSS) fluctuations was investigated by direct numerical simulations of a supersonic turbulent boundary layer over a sharp expansion corner with various deflection angles (beta = 0(0), 2(0), 5(0)and 10(0)). It is found that the two-dimensional fields of WSS are characterised as streamwise-elongated streaky structures being aligned in the spanwise direction, resembling low- and high-speed streaks in the buffer region of the flow. Due to the relaminarization effect, these WSS steaks experience a sudden weakening shortly after the expansion corner, but present gradual regrowth with their length scales even exceeding those of the flat-plate case in the far downstream. A strong streamwise-alignment of the instantaneous WSS vector is evident in the case of the largest deflection angle, suggesting a distinct reduction of the intermittency in the relaminarization process. Furthermore, the characteristic time scale of the spanwise component of WSS is quasi-invariant to the expansion effect, while the peak frequency of the streamwise component increases with the increase of the deflection angle