237 research outputs found
Investigation of Nuclear and Cytoplasmic Functions of the dLipin Protein of Drosophila Melanogaster
Lipin family proteins are highly conserved proteins present in species ranging from mammals to yeast. Lipin 1, the first Lipin gene identified in fatty liver dystrophy (fld) mutant mice, encodes the bifunctional protein Lipin 1, which can serve as an Mg2+-dependent phosphatidic acid phosphatase (PAP) and transcriptional co-regulator. dLipin, the single Lipin ortholog of Drosophila melanogaster, is required in triglyceride synthesis and fat body development. To study the transcriptional co-regulator activity of dLipin, nuclear receptors were screened to find receptors that interact with dLipin. The genetic interaction data indicated that Drosophila hepatic nuclear receptor 4 (HNF4) was a promising candidate for a protein that cooperates with dLipin in gene regulation. To study the importance of the PAP activity without disturbing the co-regulator activity, mutant flies that only express dLipin protein that lacks the PAP enzymatic activity were generated. The mutant flies showed the normal expression level and pattern of dLipin. The delta PAP mutation is lethal to Drosophila. Ectopically expressed wild type dLipin or GFP-tagged dLipin protein rescued the flies through the early lethal stage until the pupal and, in some instances, the adult stage. The phenotypes of the fat body cells of the rescued animals showed a correlation with the amount of the ectopically expressed dLipin protein. Fat body cells with low PAP enzymatic activity were round, had lost their polygonal shape and were detached from each other. They also contained very small fat droplets. Sufficient PAP enzymatic activity is needed to ensure a normal developmental rate, too. Starvation resistance was greatly impaired in dLipin-GFP-rescued delta PAP mutant heterozygotes that carried a wild-type dLipin allele. In addition, dLipin-GFP proved to be unable to translocate into the cell nucleus and it prevented nuclear translocation of endogenous wild-type dLipin. Together, these data indicate that dLipin-GFP acts in a dominant-negative manner and that nuclear activity of dLipin is required under starvation conditions
Energy Efficient Multipath TCP for Mobile Devices
Most mobile devices today come with multiple access interfaces, e.g., 4G and WiFi. Multipath TCP (MP-TCP) can greatly improve network performance by exploiting the connection diversity of multiple access interfaces, at the expense of higher energy consumption. In this paper, we design MP-TCP algorithms for mobile devices by jointly considering the performance and energy consumption. We consider two main types of mobile applications: realtime applications that have a fixed duration and file transfer applications that have a fixed data size. For each type of applications, we propose a two-timescale algorithm with theoretical guarantee on the performance. We present simulation results that show that our algorithms can reduce energy consumption by up to 22% without sacrificing throughput compared to a baseline MP-TCP algorithm
Effects of Preparation Conditions on the Yield and Embedding Ratio of Vinyl Silicone Oil Microcapsules
Self-healing materials could repair themselves without external influences when they are damaged. In this paper, microcapsules are prepared by in-situ polymerization method, utilizing vinyl silicone oil as core material, polyurea formaldehyde as wall material and polyvinyl alcohol as dispersant. The morphology and structure of the microcapsules are tested with scanning electron microscopy, optical microscopy and laser particle analyzer. Effect of the reaction temperature, stirring speed and polyvinyl alcohol concentration on the yield, embedding ratio, particle size and its distribution are studied. Results show that the microcapsules can be successfully prepared by in-situ polymerization method. Under the reaction condition of temperature 60 °C, stirring speed 1000 r/min, dispersant concentration 0.1 wt.%, the yield and embedding ratio of the microcapsule are found to be 52.5 % and 50.1 %, respectively. The prepared microcapsules have smooth surface, good dispersibility, narrow particle size distribution and the average particle size is 13 μm
Microwave-induced crystallization of AC/TiO2 for improving the performance of rhodamine B dye degradation
Effect of Yuanbao Maple Tea Powder with High Chlorogenic Acid Content on Bread Quality
Using Yuanbao maple leaves as raw materials, the extraction process of chlorogenic acid in leaves was optimized, and single-factor and orthogonal experiments were carried out on ultrasonic temperature, time, and solid-liquid ratio through ultrasonic extraction. The results showed that the optimal level of the experiment was when the ratio of solid to liquid was 16:1, the concentration of ethanol was 60%, and the ultrasonic time was 15 min, and the extraction amount was 6.86% (mass fraction). Under the optimal extraction process conditions, the dynamic content of chlorogenic acid in the growth cycle of Yuanbaofeng in 2020 was analyzed. The results showed that the content of chlorogenic acid in the leaves of Yuanbaofeng in June was the highest, and the content in September was the least. In order to further explore the effect of Yuanbao maple tea powder on bread quality, different proportions of Yuanbao maple tea powder were added to bread to study its sensory effects on bread. The effects of scores, moisture content, texture, polyphenol content, antioxidant activity and other qualities. The results show that the water holding capacity, elasticity and anti-oxidation of bread are the best when the addition amount of GTB is 0.5%. Less elastic, more difficult to chew, and gradually unstable antioxidant properties
Development of a multi-objective artificial tree (MOAT) algorithm and its application in acoustic metamaterials
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