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Synthesis and Characterization of DOPO-g-CNSL and Its Effect on the Properties of Phenolic Foams
No full textIn order to improve the mechanical properties without reducing its flame retardancy of phenolic foams (PFs), 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) was introduced in the structure of cashew nut shell liquid (CNSL) to improve its flame retardant, and the product of DOPO grafting CNSL (DOPO-g-CNSL) was obtained to modify phenolic resin, and to prepare DOPO-g-CNSL modified PFs (DCMPFs). The structures of DOPO-g-CNSL were verified by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H-NMR). Compared with CNSL, thermal stability of DOPO-g-CNSL was decreased and Ti decreased by 3.53%, but the residual carbon (800°C) was increased by 35.05%. Compared with pure PF, the mechanical properties, toughness and flame retardancy of DCMPFs were increased when the ratio of DOPO-g-CNSL to phenol (DOPO-g-CNSL/P) was no more than 10%. With the dosage of DOPO-g-CNSL/P increased, Ti of DCMPFs was slightly increased, but the carbon residues (800°C) were almost unchanged. And the cell sizes of DCMPFs were basically the same as the pure PF. By comprehensive analysis, the suitable dosage of DOPO-g-CNSL/P was no more than 10%
<i>Coxiella burnetii:</i> living inside the host cell
No full textCoxiella burnetii is an obligate intracellular pathogen and the causative agent of Q fever. In this brief review, we describe how recently described mechanisms help our understanding of C. burnetii invasion and its survival in the host cell by the formation of a replicative niche: the Coxiella-containing vacuole. We describe the actin-associated proteins involved in the internalization of C. burnetii, and we discuss the contribution of diverse degradation pathways of the cell during the formation and stabilization of the Coxiella-containing vacuole
Gene expression of 49 kDa apyrase, cytoskeletal proteins, ATPase, ADPase and amino acid contents of <i>Pisum sativum</i> (L.) cells germinated in E<i>uryops arabicus</i> (Steud. ex Jaub. & Spach) water extract
No full textThe present research reports of quick and marked changes induced by plant extract of Euryops arabicus in the
gene expression of 49-kDa apyrases, cytoskeletal proteins, ATPases, ADPase and amount of amino acid of pea (Pisum
sativum L. var. Alaska). Pellets of cytoskeletals proteins (27000 xg) were probed with anti-apyrase antibody, biotinylated
anti-rat, actin and alpha and beta-tubulin for Western blotting. ATPase and ADPase activities were determined based
on the hydrolytic efficacy of adenine triphosphate and adenine diphosphate. By 72 hours, the abundance of apyrases,
cytoskeletal proteins and amount of amino acid in pellets of 27000 xg of germinated pea seeds in E. arabicus extracts
were sharply increased than those sown in distilled water. All the samples exhibited that the stems had more amount
from apyrases, cytoskeletal proteins, amino acids and ATPase and ADPase activities than primary leaves and primary
roots that were germinated either on E. arabicus water extract or in distilled water. Based on the enzyme’s capability to
hydrolyse nucleotide triphosphate and nucleotide diphosphate as well as the direct association between expression of
49-kDa apyrase and cytoskeletal proteins, E. arabicus water extract had an important effect on plant germinations
MicroRNA expression profile and lipid metabolism characteristics in liver of rat undergoing high-fat diet
No full textThis study aimed to investigate the microRNA expression profile and the characteristics of lipid metabolism
in the livers of rats undergoing a high-fat diet. Fifty male Sprague-Dawley (SD) rats were divided into a standard chow
group (C group, N = 10) and a high-fat diet group (H group, N = 40). After 12 weeks, the rat body weight, body length,
fat mass, and serum lipid concentration were measured. The expression profile of microRNAs and the gene and protein
expression levels involved in lipid metabolism in rat liver were detected. Body fat and serum lipid concentrations
were all significantly higher in the H group than those in the C group (p p < 0.01). The expression of 10
microRNAs showed significant differences in the liver (p < 0.05). In particular, the let-7 family expression levels
significantly increased (p < 0.05) in the H group compared with those in the C group. Compared with the C group, the
high-fat diet resulted in low FAS, CPT1A, and ApoAI mRNA expression levels (p p < 0.01) and high PPARα
and FAT/CD36 mRNA expression levels in the H group rat liver (p < 0.01). Meanwhile, the protein PPARα, FAS,
CPT1A, FAT/CD36, and ApoAI expression levels were all significantly lower in the H group than those in the C group
(p p < 0.01). In conclusion, the high-fat diet increased the body fat and serum lipid levels and altered the 10
microRNA expression levels in the liver. The high-fat diet may affect hepatic carbohydrate metabolism and increase
ectopic fat accumulation through let-7 family overexpression. The high-fat diet for 12 weeks decreased lipid metabolism
level in the liver, thereby decreasing fatty acid synthesis, oxidation, and transport by down-regulating the PPARα, FAS,
CPT1A, FAT/CD36, and ApoAI protein levels
Effect of Eugenia winzerlingii Extracts on Bemisia tabaci and Evaluation of its Nursery Propagation
No full textThe development of plant-derived products to control Bemisia tabaci Genn. (Hemiptera: Aleyrodidae) is an urgent need for production of horticultural crops. Plant extracts and essential oils of several species of the genus Eugenia (Myrtaceae) have shown insecticidal activity. In southern Mexico, leaf extracts from Eugenia winzerlingii showed nematicidal effect but its insecticidal properties have not been explored. Therefore, the objective of this study was to evaluate the insecticidal effect of aqueous and organic extracts from E. winzerlingii leaves on B. tabaci egg, nymph and adult stages, and else to explore its nursery propagation. Then, extracts of this species were obtained by maceration with different polarity solvents. Bioassays were carried out on Capsicum chinense leaves. Mortality assays showed that aqueous and total crude ethanol (TCE) extracts necrosed the eggs (LC50 = 0.21% w/v and 4.68 mg/mL, respectively), whereas hexane, ethyl acetate (ETA), residual ethanol and TCE extracts affected the nymphs (LC50 = 0.25 - 4.85 mg/mL). In adults, oviposition inhibition by free choice assay indicated that TCE and ETA extracts had major activity (EC50 = 14.62 and 27.86 μg/cm2, respectively). On other hand, the sexual and vegetative propagation of E. winzerlingii showed that this species can be easily cultivated by seeds. In conclusion, extracts of E. winzerlingii leaves are highly effective in controlling B. tabaci. TCE extract, in particular, was toxic to three stages of B. tabaci. This plant could be a potential alternative to develop a novel botanical insecticide to manage this destructive pest
Detection of ROS and translocation of ERP-57 in apoptotic induced human neuroblastoma (SH-SY5Y) cells
No full textSeveral toxic compounds are known to induce apoptosis in mammalian cell lines. The human neuroblastoma
cells (SH-SY5Y) were exposed to the phosphatase inhibiting toxin okadaic acid (OA) or hydrogen peroxide (H2O2)
to induce apoptosis as well as generate reactive oxygen species (ROS). Mitoxantrone (MXT) was used as a positive
control for apoptosis. The SH-SY5Y cells were transfected with eukaryotic expression plasmid pHyPer-dMito encoding
mitochondrial-targeted fluorescent or pHyPer-dCito encoding cytoplasmic-targeted fluorescent sensor for hydrogen
peroxide (HyPer). The ERp57, also called GRP58 (Glucose-regulated protein 58), is a stress protein induced in
conditions like glucose starvation and viral infection. Recently ERp57 was shown to translocate from the endoplasmatic
reticulum to the cell surface in anthracycline-induced apoptotic cells. ERp57 co-translocation together with calreticulin
has been suggested to be crucial for recognizing tumor cells to induce immunogenic cell death. ERp57 translocation
after exposure to okadaic acid was studied using immunofluorescence and confocal microscopy. These studies indicated
that okadaic acid has induced the translocation of ERp57 to the cellular membrane
Antifungal Activity of Schinifoline Against Candida Albicans in Caenorhabditis Elegans
No full textZanthoxylum schinifolium has been used as spices and traditional medicine in China for hundreds of years. A variety of active substances have been isolated from Zanthoxylum schinifolium using biological and chemical techniques. Among these substances, the effect of schinifoline has gradually attracted much attention. Candida albicans is one of the most common pathogens isolated from the gastrointestinal tract, vagina, and mouth in healthy individuals. In a healthy population, there are various mechanisms in host, such as the microbial flora, the epithelial barriers, and the innate immune system, that can control the presence of Candida albicans. However, when host immunity is compromised, an invasive fungal infection is more likely to occur. In this study, we explored the antifungal activity of schinifoline against Candida albicans in Caenorhabditis elegans. To determine the optimal concentration of schinifoline, we investigated the lifespan, defecation cycle and locomotion behavior of Caenorhabditis elegans after treatment with schinifoline. In addition, we examined colony formation in the intestine of Caenorhabditis elegans after Candida albicans infection. The results indicated that 100 and 200 mg/L of schinifoline could prolonged the lifespan, shorten the defecation cycle and increased the locomotion behavior of Caenorhabditis elegans, with 100 mg/L of schinifoline being the optimal concentration. Moreover, 100 mg/L of schinifoline increased the lifespan of Caenorhabditis elegans after infection and inhibited the colony formation of Candida albicans in Caenorhabditis elegans intestine. Therefore, we concluded that schinifoline exhibits anti-fungal effects and its potential use as natural drugs should be further explored in future studies
Efficient Computation Offloading in Mobile Cloud Computing for Video Streaming Over 5G
No full textIn this paper, we investigate video quality enhancement using computation offloading to the mobile cloud computing (MCC) environment. Our objective is to reduce the computational complexity required to covert a low-resolution video to high-resolution video while minimizing computation at the mobile client and additional communication costs. To do so, we propose an energy-efficient computation offloading framework for video streaming services in a MCC over the fifth generation (5G) cellular networks. In the proposed framework, the mobile client offloads the computational burden for the video enhancement to the cloud, which renders the side information needed to enhance video without requiring much computation by the client. The cloud detects edges from the upsampled ultra-high-resolution video (UHD) and then compresses and transmits them as side information with the original low-resolution video (e.g., full HD). Finally, the mobile client decodes the received content and integrates the SI and original content, which produces a high-quality video. In our extensive simulation experiments, we observed that the amount of computation needed to construct a UHD video in the client is 50%-60% lower than that required to decode UHD video compressed by legacy video encoding algorithms. Moreover, the bandwidth required to transmit a full HD video and its side information is around 70% lower than that required for a normal UHD video. The subjective quality of the enhanced UHD is similar to that of the original UHD video even though the client pays lower communication costs with reduced computing power
An Efficient Quantum Key Distribution Protocol with Dense Coding on Single Photons
No full textCombined with the dense coding mechanism and the bias-BB84 protocol, an efficient quantum key distribution protocol with dense coding on single photons (QDKD-SP) is proposed. Compared with the BB84 or bias-BB84 protocols based on single photons, our QDKD-SP protocol has a higher capacity without increasing the difficulty of its experiment implementation as each correlated photon can carry two bits of useful information. Compared with the quantum dense key distribution (QDKD) protocol based on entangled states, our protocol is more feasible as the preparation and the measurement of a single-photon quantum state is not difficult with current technology. In addition, our QDKD-SP protocol is theoretically proved to be secure against the intercept-resend attack
A Dynamic Memory Allocation Optimization Mechanism Based on Spark
No full textSpark is a distributed data processing framework based on memory. Memory allocation is a focus question of Spark research. A good memory allocation scheme can effectively improve the efficiency of task execution and memory resource utilization of the Spark. Aiming at the memory allocation problem in the Spark2.x version, this paper optimizes the memory allocation strategy by analyzing the Spark memory model, the existing cache replacement algorithms and the memory allocation methods, which is on the basis of minimizing the storage area and allocating the execution area according to the demand. It mainly including two parts: cache replacement optimization and memory allocation optimization. Firstly, in the storage area, the cache replacement algorithm is optimized according to the characteristics of RDD Partition, which is combined with PCA dimension. In this section, the four features of RDD Partition are selected. When the RDD cache is replaced, only two most important features are selected by PCA dimension reduction method each time, thereby ensuring the generalization of the cache replacement strategy. Secondly, the memory allocation strategy of the execution area is optimized according to the memory requirement of Task and the memory space of storage area. In this paper, a series of experiments in Spark on Yarn mode are carried out to verify the effectiveness of the optimization algorithm and improve the cluster performance