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61.
62.
Molecular Biology Reports - Thelandros is a genus of oxyurid nematodes which parasitize both omnivorous and herbivorous hosts. Thelandros chalcidiae sp. nov. is a new taxa described from the large...  相似文献   
63.
A Short cut graphical procedure has been developed analogous to stepwise for the design of continuous flow sedimentation or thickening tanks.In this technique, several computer programs have been set up in order to reduce the data input, necessary for performing all intermediate calculations by computer. The data describing the settling of particles and movement of the particle-liquid interface as a function of time and operating conditions are the only data required. The method predicts the time required to attain the prescribed underflow concentration, the rate of hindered settling subsidence, the area required for clarification, the thickener area and dimensions. The proposed method has been applied to illustrate the effect of different chemical treatment doses on a typical industrial effluent from the manufacture of starch and byproducts from American yellow corn.List of Symbols A1 cm First falling zone line intercept - A2 cm Settling zone curve intercept - A3 cm Compression zone line intercept - A4 cm Angle bisector intercept - A5 cm Tangent interception at the compression point - ACL m2 Minimum clarification area - ALPHA() Angle between line 1 and line 2, radians - ATH m2 Minimum thickening area - ATH1 m2 Area of each individual tank - B1 cm · min–1 First falling zone line slope - B2 Settling zone curve power - B3 cm · min–1 Compression zone line slope - B4 cm · min–1 Angle bisector slope - B5 cm · min–1 Tangent slope at the compression point - BT m Approximate width of the tank - BT1 m Actual width of the tank - CC Conversion criteria - CO mg/dm3 Initial solid concentration - CU mg/dm3 Underflow solid concentration - D m Basin depth - DIAM m Diameter of circular tank - DMIN m Minimum allowable liquid depth - DT h Minimum allowable detention time - DT1 h Calculated detention time - HT cm Subsiding particle-liquid interface height - HT1 min Subsiding particle-liquid interface coordinate for line 1 and line 2 intersection - HTR cm Subsiding particle-liquid interface coordinate for compression point - L m Approximate length of the tank - L1 m Actual length of the tank - LMAX m Maximum allowable tank length - LMIN m Minimum allowable tank length - NI Number of iterations - NO Number of tanks - PI Const. - Q m3/h Wastewater flowrate - SL m3/(m2 · d) Surface loading - T1 Tan() - T3 Tan (/2) - TM min Time of measuring subsiding particle-liquid interface - TM1 min Time coordinate for line 1 and line 2 intersection - TML min Lower limit of the root - TMR min Time coordinate for compression point - TMU min Upper limit of the root - TU min Time required to attain underflow concentration - ZO cm Initial height of sludge - ZU cm Settled height of sludge interface - FI m Inert depth (typically taken as 1 m)  相似文献   
64.
Traditional models of insect vision have assumed that insects are only capable of low-level analysis of local cues and are incapable of global, holistic perception. However, recent studies on honeybee (Apis mellifera) vision have refuted this view by showing that this insect also processes complex visual information by using spatial configurations or relational rules. In the light of these findings, we asked whether bees prioritize global configurations or local cues by setting these two levels of image analysis in competition. We trained individual free-flying honeybees to discriminate hierarchical visual stimuli within a Y-maze and tested bees with novel stimuli in which local and/or global cues were manipulated. We demonstrate that even when local information is accessible, bees prefer global information, thus relying mainly on the object''s spatial configuration rather than on elemental, local information. This preference can be reversed if bees are pre-trained to discriminate isolated local cues. In this case, bees prefer the hierarchical stimuli with the local elements previously primed even if they build an incorrect global configuration. Pre-training with local cues induces a generic attentional bias towards any local elements as local information is prioritized in the test, even if the local cues used in the test are different from the pre-trained ones. Our results thus underline the plasticity of visual processing in insects and provide new insights for the comparative analysis of visual recognition in humans and animals.  相似文献   
65.
Hydrophobins represent an important group of proteins from both a biological and nanotechnological standpoint. They are the means through which filamentous fungi affect their environment to promote growth, and their properties at interfaces have resulted in numerous applications. In our study we have combined protein docking, molecular dynamics simulation, and electron cryo-microscopy to gain atomistic level insight into the surface structure of films composed of two class II hydrophobins: HFBI and HFBII produced by Trichoderma reesei. Together our results suggest a unit cell composed of six proteins; however, our computational results suggest P6 symmetry, while our experimental results show P3 symmetry with a unit cell size of 56 Å. Our computational results indicate the possibility of an alternate ordering with a three protein unit cell with P3 symmetry and a smaller unit cell size, and we have used a Monte Carlo simulation of a spin model representing the hydrophobin film to show how this alternate metastable structure may play a role in increasing the rate of surface coverage by hydrophobin films, possibly indicating a mechanism of more general significance to both biology and nanotechnology.  相似文献   
66.
International Journal of Peptide Research and Therapeutics - β-secretase 1 (BACE1) plays a pivotal role in the pathology of Alzheimer?s disease via accumulation beta amyloid in the...  相似文献   
67.
The genome of the anaerobic halophilic alkalithermophile Natranaerobius thermophilus consists of one 3,165,557-bp chromosome and two plasmids (17,207 bp and 8,689 bp). The present study is the first to report the completely sequenced genome of an anaerobic polyextremophile and genes associated with roles in regulation of intracellular osmotic pressure, pH homeostasis, and growth at elevated temperatures.  相似文献   
68.
The farnesoid X receptor (FXR) is involved in glucose and lipid metabolism regulation, which makes it an attractive target for the metabolic syndrome, dyslipidemia, atherosclerosis, and type 2 diabetes. In order to find novel FXR agonists, a structure-based pharmacophore model collection was developed and theoretically evaluated against virtual databases including the ChEMBL database. The most suitable models were used to screen the National Cancer Institute (NCI) database. Biological evaluation of virtual hits led to the discovery of a novel FXR agonist with a piperazine scaffold (compound 19) that shows comparable activity as the endogenous FXR agonist chenodeoxycholic acid (CDCA, compound 2).  相似文献   
69.
We investigated the phylogenetic diversity and metabolic capabilities of members of the phylum Planctomycetes in the anaerobic, sulfide-saturated sediments of a mesophilic spring (Zodletone Spring) in southwestern Oklahoma. Culture-independent analyses of 16S rRNA gene sequences generated using Planctomycetes-biased primer pairs suggested that an extremely diverse community of Planctomycetes is present at the spring. Although sequences that are phylogenetically affiliated with cultured heterotrophic Planctomycetes were identified, the majority of the sequences belonged to several globally distributed, as-yet-uncultured Planctomycetes lineages. Using complex organic media (aqueous extracts of the spring sediments and rumen fluid), we isolated two novel strains that belonged to the Pirellula-Rhodopirellula-Blastopirellula clade within the Planctomycetes. The two strains had identical 16S rRNA gene sequences, and their closest relatives were isolates from Kiel Fjord (Germany), Keauhou Beach (HI), a marine aquarium, and tissues of marine organisms (Aplysina sp. sponges and postlarvae of the giant tiger prawn Penaeus monodon). The closest recognized cultured relative of strain Zi62 was Blastopirellula marina (93.9% sequence similarity). Detailed characterization of strain Zi62 revealed its ability to reduce elemental sulfur to sulfide under anaerobic conditions, as well as its ability to produce acids from sugars; both characteristics may potentially allow strain Zi62 to survive and grow in the anaerobic, sulfide- and sulfur-rich environment at the spring source. Overall, this work indicates that anaerobic metabolic abilities are widely distributed among all major Planctomycetes lineages and suggests carbohydrate fermentation and sulfur reduction as possible mechanisms employed by heterotrophic Planctomycetes for growth and survival under anaerobic conditions.  相似文献   
70.
The aim of the present study was to utilize chitosan (CS) nanoparticles for the intracellular delivery of the poorly cell-penetrating antibiotic, ceftriaxone sodium (CTX). In vitro characterization of (CTX-CS) nanoparticles was conducted leading to an optimized formula that was assessed for its biocompatibility to blood (hemolysis test) and cells (MTT assay). Progressively, confocal laser scanning microscopy (CLSM), cellular uptake (microfluorimetry), and antibacterial activity of the nanoparticles were investigated in two cell lines: Caco-2 and macrophages J774.2 pre-infected with Salmonella typhimurium. Results showed that the optimized formula had size 210 nm, positive zeta potential (+30 mV) and appreciable entrapment efficiency for CTX (45%) and included a biphasic release pattern. The nanoparticles were biocompatible and were internalized by cells as verified by CLSM whereas microfluorimetry indicated substantial cellular uptake. Moreover, the CTX–chitosan nanoparticles showed a significant reduction in the count of intracellular S. typhimurium in Caco-2 and macrophages J774.2. This reduction was significantly higher than that obtained in case of placebo nanoparticles, CTX, and CTX–chitosan solutions and might be attributed to enhanced endocytic uptake of the nanoaprticles and antibacterial effect of the chitosan polymer. In conclusion, the results provide evidence for the potential use of chitosan nanoparticles to enhance the intracellular delivery and antibacterial effect of CTX in enterocytes and macrophages.Key words: ceftriaxone sodium, chitosan nanoparticles, enterocytes, intracellular delivery, macrophages  相似文献   
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