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51.
The ectoparasitic mite Dorsipes caspius n. sp. (Heterostigmata: Podapolipidae) belonging to the platysmae species group collected from the beneath elytra of Pterostichus (Lyrothorax) caspius (Menetries) (Coleoptera: Carabidae) in northern Iran, is described. This is the first record of species of the platysmae group from the Middle East. Keys to adult and larval female stages of world species of the platysmae group are provided. The host range of all species of the genus and the distribution of all representatives of the group are discussed.  相似文献   
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Genome-wide association studies (GWAS) have been instrumental in identifying novel genetic variants associated with altered plasma lipid levels. However, these quantitative trait loci have not been tested in the Indian population, where there is a poorly understood and growing burden of cardiometabolic disorders. We present the association of six single nucleotide polymorphisms in 1671 sib pairs (3342 subjects) with four lipid traits: total cholesterol, triglycerides, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C). We also investigated the interaction effects of gender, location, fat intake and physical activity. Each copy of the risk allele of rs964184 at APOA1 was associated with 1.06 mmol/l increase in triglycerides (SE = 0.049; p = 0.006), rs3764261 at CETP with 1.02 mmol/l increase in both total cholesterol (SE = 0.042; p = 0.017) and HDL-C (SE = 0.041; p = 0.008), rs646776 at CELSR2-PSRC1-SORT1 with 0.96 mmol/l decrease in cholesterol (SE = 0.043; p = 0.0003) and 0.15 mmol/l decrease in LDL-C levels (SE = 0.043; p = 0.0003) and rs2954029 at TRIB1 with 1.02 mmol/l increase in HDL-C (SE = 0.039; p = 0.047). A combined risk score of APOA1 and CETP loci predicted an increase of 1.25 mmol/l in HDL-C level (SE = 0.312; p = 0.0007). Urban location and sex had strong interaction effects on the genetic association of most of the studied loci with lipid traits. To conclude, we validated four genetic variants (identified by GWAS in western populations) associated with lipid traits in the Indian population. The interaction effects found here may explain the sex-specific differences in lipid levels and their heritability. Urbanization appears to influence the nature of the association with GWAS lipid loci in this population. However, these findings will require replication in other Indian populations.  相似文献   
54.
Middle East respiratory syndrome coronavirus(MERS-Co V) has emerged in the Arabian Gulf region, with its epicentre in Saudi Arabia, the host of the ‘Hajj' which is the world's the largest mass gathering. Transmission of MERS-Co V at such an event could lead to its rapid worldwide dissemination. Therefore, we studied the frequency of viruses causing influenza-like illnesses(ILI) among participants in a randomised controlled trial at the Hajj 2013. We recruited 1038 pilgrims from Saudi Arabia, Australia and Qatar during the first day of Hajj and followed them closely for four days. A nasal swab was collected from each pilgrim who developed ILI. Respiratory viruses were detected using multiplex RT-PCR. ILI occurred in 112/1038(11%) pilgrims. Their mean age was 35 years, 49(44%) were male and 35(31%) had received the influenza vaccine pre-Hajj. Forty two(38%) pilgrims had laboratory-confirmed viral infections; 28(25%) rhinovirus, 5(4%) influenza A, 2(2%) adenovirus, 2(2%) human coronavirus OC43/229 E, 2(2%) parainfluenza virus 3, 1(1%) parainfluenza virus 1, and 2(2%) dual infections. No MERS-Co V was detected in any sample. Rhinovirus was the commonest cause of ILI among Hajj pilgrims in 2013. Infection control and appropriate vaccination are necessary to prevent transmission of respiratory viruses at Hajj and other mass gatherings.  相似文献   
55.

Background:

One area of nanoscience deals with nanoscopic interactions between nanostructured materials and biological systems. To elucidate the effects of the substrate surface morphology and viscoelasticity on cell proliferation, fractal analysis was performed on endothelial cells cultured on nanocomposite samples based on silicone rubber (SR) and various concentrations of organomodified nanoclay (OC).

Methods:

The nanoclay/SR ratio was tailored to enhance cell behavior via changes in sample substrate surface roughness and viscoelasticity.

Results:

Surface roughness of the cured SR filled with negatively-charged nanosilicate layers had a greater effect than elasticity on cell growth. The surface roughness of SR nanocomposite samples increased with increasing the OC content, leading to enhanced cell growth and extracellular matrix (ECM) remodeling. This was consistent with the decrease in SR segmental motions and damping factor as the primary viscoelastic parameters by the nanosilicate layers with increasing clay concentrations.

Conclusions:

The inclusion of clay nanolayers affected the growth and behavior of endothelial cells on microtextured SR.Key Words: Silicone rubber, Nanoclay, Elastic Modulus, Roughness, Cell proliferation  相似文献   
56.
Ten tomato genotypes were screened for their resistance against cucumber mosaic virus (CMV) and its vector Myzus persicae under natural infection in field, using aphids M. persicae under net-house and mechanical inoculation under greenhouse. Large differences were observed among genotypes for infection percentage (IP) and severity index (SI) among the testing methods used. All genotypes showing tolerance to CMV in the field or through aphid inoculation, however, become susceptible and highly susceptible after mechanical inoculation. All the test genotypes also showed susceptibility to the aphid M. persicae population. Plants inoculated with CMV showed substantial decrease in yield and yield-contributing parameters which varied with cultivars that probably depended upon its genetic make up. All the test genotypes exhibited 0.97–30.19% decrease in plant height, 11.47–52.65% decrease in root length, 46.56–95.56% decrease in fresh plant weight, 65.78–92.84% decrease in root fresh weight, 19.97–87.65% decrease in the dry weight of plants, 75.63–95.43% decrease in dry root weight, 69.51–95.65% reduction in the number of fruits and 89.04–99.89% decrease in yield per plants. After 15 days of inoculation, the quantitative analysis using double beam spectrophotometer showed an increase in total phenolics in CMV-inoculated plants as compared to un-inoculated plants among genotypes. Similarly the thin layer chromatography (TLC) on silica gel G indicated that the number of phenolic compounds was increased in most of the inoculated genotypes while in others they were either decreased or remained same.  相似文献   
57.
Microbial fuel cells (MFCs) have been shown to be capable of clean energy production through the oxidation of biodegradable organic waste using various bacterial species as biocatalysts. In this study we found Saccharomyces cerevisiae, previously known electrochemcially inactive or less active species, can be acclimated with an electron mediator thionine for electrogenic biofilm formation in MFC, and electricity production is improved with facilitation of electron transfer. Power generation of MFC was also significantly increased by thionine with both aerated and non-aerated cathode. With electrochemically active biofilm enriched with swine wastewater, MFC power increased more significantly by addition of thionine. The optimum mediator concentration was 500 mM of thionine with S. cerevisae in MFC with the maximum voltage and current generation in the microbial fuel cell were 420 mV and 700 mA/m(2), respectively. Cyclic voltametry shows that thionine improves oxidizing and reducing capability in both pure culture and acclimated biofilm as compared to non-mediated cell. The results obtained indicated that thionine has great potential to enhance power generation from unmediated yeast or electrochemically active biofilm in MFC.  相似文献   
58.

To encapsulate piperine (Pip), as a poor water-soluble bioactive compound, zein-sodium caseinate-xanthan gum (Z-SG-XG) nanocomplex was prepared as a colloidal delivery system. The effect of different parameters involved in complexation process, including concentration of proteins, polysaccharide, and Pip on the encapsulation efficiency of Pip, particle size and stability of the nanocomplexes was investigated. Powders obtained by freeze-drying of the colloidal solution had relatively uniform particles compared to those obtained from conventional drying system and showed well redispersibility in water. At the optimal condition, a stable and homogeneous nanocomplex with a mean particle size of 145.9 ± 2.7 nm, PDI of 0.27 ± 0.01, and ζ-potential of −39.7 ± 1.3 mV was obtained. The antioxidant activity of Pip was significantly improved by encapsulation into the Z-SC-XG nanocomplex. Also, the in vitro release of Pip from the synthesized nanocomplexes in phosphate-buffer saline (PBS) solution and simulated gastrointestinal fluids (SGIF) was investigated and the release kinetic was studied as well. The Pip/Z-SG-XG nanocomplex showed a slower release in SGIF compared to the free Pip and nanoparticles without XG and SC, while its antioxidant activity was remarkable. Results suggested a possible utilization of Z-SC-XG nanocomplex for improving the water solubility, bioavailability and storage stability of Pip.

  相似文献   
59.
Protoplasma - One of the classes of the plant developmental programmed cell death (PCD) is vacuolar cell death or autolysis. The results of the transmission electron microscope (TEM) studies...  相似文献   
60.
Biomechanics and Modeling in Mechanobiology - Every group of microorganism utilizes a diverse mechanical strategy to propel through complex environments. These swimming problems deal with the...  相似文献   
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