2,410 research outputs found
A Two-Dimensional CA Traffic Model with Dynamic Route Choices Between Residence and Workplace
The Biham, Middleton and Levine (BML) model is extended to describe dynamic
route choices between the residence and workplace in cities. The traffic
dynamic in the city with a single workplace is studied from the velocity
diagram, arrival time probability distribution, destination arrival rate and
convergence time. The city with double workplaces is also investigated to
compared with a single workplace within the framework of four modes of urban
growth. The transitional region is found in the velocity diagrams where the
system undergoes a continuous transition from a moving phase to a completely
jamming phase. We perform a finite-size scaling analysis of the critical
density from a statistical point of view and the order parameter of this
jamming transition is estimated. It is also found that statistical properties
of urban traffic are greatly influenced by the urban area, workplace area and
urban layout.Comment: 18 pages, 13 figure
Cloning, Identification, and Characterization of the rpoS-Like Sigma Factor rpoX from Vibrio alginolyticus
Vibrio alginolyticus ZJ-51 displays phase variation between opaque/rugose colonies (Op) and translucent/smooth colonies (Tr). These colony variants show great differences in biofilm formation and motility. In this study, a gene encoding for an rpoS-like sigma factor, rpoX, has been cloned and characterized. The absence of rpoX did not affect colony switching rate but did decrease biofilm formation in both the Op and the Tr variants. When challenged with hydrogen peroxide, the ΔrpoX in the Op background showed a slightly higher survival rate compared with the wild type, whereas survival was decreased in the Tr background. Deletion of rpoX in the Tr background resulted in a higher ability to resist ethanol challenges and to survive hyperosmolarity challenges, and in the Op background the opposite phenotype was observed. This indicates that the rpoX gene is involved in biofilm formation and stress response but the effects are controlled by colony phase variation in V. alginolyticus
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Down-Shifting Nanoparticles and Anti-reflective Nanoparticles Co-Coating Applied on Top Glass Cover of Silicon-Based Solar Panels
Photoluminescence (PL) materials have attracted a lot of attention in last several decades. Recently PL materials, which can convert low-efficiency Ultraviolet (UV) or Infrared (IR) light to high-efficiency visible light, have been widely applied in the research of improving conversion efficiency of solar cell. As one of the most common PL materials, YVO₄:Eu³⁺ Down-shifting (DS) Nanoparticles (NPs) are well researched for improving conversion efficiency of solar cell by prior researchers. However, the transmittance lose due to high reflectance of YVO₄:Eu³⁺ NPs is always the biggest challenge. In this thesis, antireflective materials, hollow silica NPs, are coated with YVO₄:Eu³⁺ NPs for the first time to decrease the reflectance of the YVO₄:Eu³⁺ NPs. Two different morphologies of YVO₄:Eu³⁺ NPs and four DS and/or AR coating modules are compared respectively in this research. In addition, the DS and AR NPs co-coating can improve the solar cell efficiency of Si-based solar cell by 6.54 than the efficiency of Si-based solar cell without DS and AR NPs co-coating
Bis[(diphenylphosphanylmethyl)diphenylphosphane sulfide-κ2 P,S]copper(I) hexafluoridophosphate
In the title compound, [Cu(C25H22P2S)2]PF6, the CuI atom, lying on a twofold rotation axis, adopts a distorted tetrahedral geometry. The (diphenylphosphanylmethyl)diphenylphosphane sulfide ligand coordinates to the CuI atom through one S and one P atom, forming a stable five-membered chelate ring. The P atom of the PF6
− anion also lies on a twofold rotation axis
Chloridobis(1,2,3,4-tetrahydro-1,4,6,11-tetraazanaphthacene-κN 6)copper(I)
In the title complex, [CuCl(C14H12N4)2], the CuI atom, lying on a twofold rotation axis, is coordinated by two N atoms of two 1,2,3,4-tetrahydro-1,4,6,11-tetraazanaphthacene ligands and one Cl atom, also lying on the twofold rotation axis, in a distorted trigonal-planar geometry. The complex molecules are connected into a one-dimensional structure along [001] via N—H⋯N hydrogen bonds and further into a three-dimensional structure via N—H⋯Cl hydrogen bonds. π–π interactions between the pyrazine and benzene rings and between the benzene rings [centroid–centroid distances = 3.5635 (15) and 3.9128 (16) Å] are present
Gentiana macrophylla Pall (Gentianaceae) extract exerts protective effects against osteoporosis in mice
Purpose: To evaluate the anti-osteoporotic effect of G. macrophylla extract in a mice model.Methods: Antioxidant activity was determined by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) for radical scavenging, nitro-blue tetrazolium (NBT) reducing, and ferric reducing antioxidant power (FRAP) assays using standard biochemical procedures. The expression of some bone-related genes was measured by quantitative real-time polymerase chain reaction (qTR-PCR). Phytochemical analysis was carried out by liquid chromatography-mass spectrometry (LC/MS).Results: The extract exhibited strong antioxidant activity as evident from DPPH, NBT and FRAP data, with half-maximal inhibitory concentration (IC50) values of 275, 262 and 180 μg/ml, respectively. The antioxidant activity was concentration-dependent. The results showed that the extract restored bone characteristics by suppressing bone resorption through induction of expressions of several boneassociated genes. The results from phytochemical analyses showed the presence of loganic acid, swertiamarin, sweroside, gentiopicroside, gentesin and isogentesin.Conclusion: These results indicate that the extract may be beneficial in the treatment of osteoporosis.Keywords: Gentiana macrophylla, Osteoporosis, Bone mass, Loganic acid, Swertiamarin, Sweroside, Gentiopicroside, Gentesi
Nutritional profiles of tiger Nut (Cyperus esculentus) plant organs during its growth cycle
This study was carried out to determine major nutrient profiles changes of tiger nut plant during its growth period. The plant leaves, roots, tuber moisture, starch, fat and protein were analyzed by oven drying, enzymatic hydrolysis, glucose assay, soxhlet extraction and kjeldahl methods. The results show the moisture content was decreased during its growth cycle but varied with different plant organ. For leaves, the starch content was increased with reducing oil content. For roots, oil content was highest (8%) at the 100th day, and it was gradually decreased (3%) till harvest time with non-significant changes of starch content. For tuber, reducing sugar and protein content was insignificant where the starch and oil content increased significantly but the changes were irregular in the middle growing. For optimum macronutrient yields, it is recommended to harvest the plant at 142nd day for starch. The delayed harvesting may lead to increase in oil content while reducing its total starch contents. For the starch purpose, the harvest time could be around 142 days. However, harvest time could require staying longer in soil.Keywords: Tiger nut, oil, starch, growth cycle, nutrients enrichmen
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