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171.
Eimeria sinaitae n. sp. is described from the gall bladder of Agama sinaita from Wasie, Saudi Arabia. Sporulated oocysts are elongate-ellipsoid 34.4 times 22.0 (29.0–40.0 times 17.4–24.5) μm. Oocyst wall is smooth, greenish yellow, 1.2 (1.0–1.4) μm thick, and two-layered. Micropyle, polar granule, and oocyst residuum are absent. Sporocysts are ellipsoid 11.4 times 7.6 (9.8–15.0 times 6.7–9.0) μm. Sporocyst residuum is present. The sporocysts lack a Stieda body. Sporozoites are crescent-shaped, blunt at one end and tapered at the other. Eimeria species from Agamidae are compared.  相似文献   
172.
Constraints created by immobilization conditions modified the physiological behavior and morphological characteristics of Gibberella fujikuroi mycelia in comparison with their development in free-cell conditions. G. fujikuroi mycelia were immobilized in different support matrices (polyurethane, carrageenan, and alginate) and showed a variety of reactions in response to the different microenvironmental factors encountered during and after immobilization. The best support with respect to gibberellic acid yield and biocatalyst stability was found to be an alginate with a high degree of polymerization. The most visible effects of immobilization included changes in growth development, morphological appearance, metabolite production, mycelial pigmentation, mycelial viability under starvation conditions, and induction of resting forms when previously immobilized mycelia were subcultured.  相似文献   
173.
Support materials of low‐density for fluidized bed reactors provide several operational advantages, including lower energy requirements and proper biofilm growth balance. The aim of this investigation was to study the extent of biofilm growth and bed fluidization in an experimental reactor, using polyester resin (ρpr = 1220 kg/m3) and vitrified expanded perlite (ρvep = 1710 kg/m3) as alternative support materials to conventional silica sand. A noteworthy amount of biofilm was observed to be attached to both support materials from the very beginning of the bioreactor operation. Nevertheless, there were significant variations in biofilm growth and activity over the course of the experimental trials. For both perlite and polyester beds, the highest biofilm mass and the highest total number of mesophilic bacteria were observed between the 7th and the 10th day, showing a steady state trend at the end of the experimental runs. The chemical oxygen demand (COD) removal levels were concomitant with biofilm mass and total mesophilic bacteria changes, although the polyester bed efficiency was slightly higher than that for the perlite bed. As expected, the polyester bed was fluidized at a lower re‐circulation flow compared to the perlite bed. Reactor back‐washing was not required for these support materials since biomass excess was adequately separated by means of a special internal device. The efficiencies of removal of organic matter achieved were acceptable (up to 78 %) despite the low volume of the support material (25 %) and the low hydraulic retention time (30 min).  相似文献   
174.
Abstract: Water-soluble protein fractions from leaves, seeds and heads of sunflower were shown to contain inhibitors of trypsin, chymotrypsin and extracellular proteinases from Sclerotinia sclerotiorum , a pathogen of sunflower, and Colletotrichum lindemuthianum. These included bifunctional inhibitors of trypsin and subtilisin. Comparison with the patterns of inhibition of standard proteinases indicated that the major extracellular proteinases of S. sclerotiorum are subtilisin-like. It is speculated that the sunflower inhibitors play a role in conferring resistance to fungal infection.  相似文献   
175.
The presence of organic ligands in a solution containing metal ions modifies metal speciation, which in turn changes the sorption mechanism, optimum pH range and maximum sorption capacity. The present work investigates the sorption of copper by chitosan in the presence of citrate at different metal/ligand ratios. Copper uptake in acidic solution takes place through electrostatic attraction between the protonated amine groups of chitosan and anionic copper-citrate complexes (mainly Cu(OH)L2- but also a small fraction of CuL-). Sorption was negligible below pH 3 due to competition from dissociated anionic ligand and counter ions brought about by dissociation of the acid used for pH control. Actually, copper sorption begins to be significant when the fraction of anionic copper-complexes exceeds that of anionic copper-free ligand. So sorption capacity strongly increases up to pH 4.5-5.5. Above pH 5.5, the progressive decrease of amine protonation leads to a linear decrease in sorption capacity. An excess of ligand leads to an increase in the fraction of free dissociated (anionic) ligand that may compete for electrostatic attraction on protonated amine groups and therefore leads to a decrease in sorption capacities.  相似文献   
176.
There is a public perception that the white‐tailed deer Odocoileus virginianus (Artiodactyla: Cervidae) is the main reservoir supporting the maintenance and spread of the causative agent of Lyme disease, Borrelia burgdorferi. This study examines the pathogen prevalence rate of Borrelia in adult Ixodes scapularis (Ixodida: Ixodidae), the black‐legged tick, collected from white‐tailed deer and compares it with pathogen prevalence rates in adult ticks gathered by dragging vegetation in two contiguous counties west of the Hudson Valley in upstate New York. In both Broome and Chenango Counties, attached and unattached ticks harvested from white‐tailed deer had significantly lower prevalences of B. burgdorferi than those collected from vegetation. No attached ticks on deer (n = 148) in either county, and only 2.4 and 7.3% of unattached ticks (n = 389) in Broome and Chenango Counties, respectively, were harbouring the pathogen. This contrasts with the finding that 40.8% of ticks in Broome County and 46.8% of ticks in Chenango County collected from vegetation harboured the pathogen. These data suggest that a mechanism in white‐tailed deer may aid in clearing the pathogen from attached deer ticks, although white‐tailed deer do contribute to the spatial distribution of deer tick populations and also serve as deadend host breeding sites for ticks.  相似文献   
177.
The PLAGL1 gene encodes a homonymous zinc finger protein that promotes cell cycle arrest and apoptosis through multiple pathways. The protein has been implicated in metabolic, genetic, and neoplastic illnesses, but the molecular mechanisms by which the protein PLAGL1 participates in such diverse processes remains to be elucidated. In this review, we focus mainly on the molecular biology of PLAGL1 and the relevance of its abnormalities to several pathological processes.  相似文献   
178.
We determined the effects of temperature and nutrients on thechain length of a diatom, Skeletonema costatum, in batch cultureand enclosure experiments with estuarine water from San FranciscoBay, USA, using the recently developed CytoBuoy flow cytometer.Determination of the number of cells per diatom chain by CytoBuoyflow cytometer and associated software correlated well withbut was much more precise and time efficient than microscopicquantification. Increasing temperatures (from 6, 8 to 17°C)and nutrient concentrations induced high growth rates and dominanceby longer chains in a cultured S. costatum strain that was originallyacclimatized to a temperature range of 11–30°C. Similarly,a positive correlation between growth rate and chain lengthwas observed in S. costatum in batch culture and natural communitiesin enclosure experiments. Maximal chain lengths of S. costatumwere greater in natural populations than in the batch culture.Longer chains affect sinking rates and thus likely help thediatom remain suspended in the upper part of the water columnwhere physical and chemical parameters are more favorable forgrowth.  相似文献   
179.
The highest enzymatic extraction of covalent linked chlorogenic (36.1%) and caffeic (CA) (33%) acids from coffee pulp (CP) was achieved by solid‐state fermentation with a mixture of three enzymatic extracts produced by Aspergillus tamarii, Rhizomucor pusillus, and Trametes sp. Enzyme extracts were produced in a practical inexpensive way. Synergistic effects on the extraction yield were observed when more than one enzyme extract was used. In addition, biotransformation of chlorogenic acid (ChA) by Aspergillus niger C23308 was studied. Equimolar transformation of ChA into CA and quinic acids (QA) was observed during the first 36 h in submerged culture. Subsequently, after 36 h, equimolar transformation of CA into protocatechuic acid was observed; this pathway is being reported for the first time for A. niger. QA was used as a carbon source by A. niger C23308. This study presents the potential of using CP to produce enzymes and compounds such as ChA with biological activities. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29: 337–345, 2013  相似文献   
180.
J AL Armour  A Davison  I C McManus 《Heredity》2014,112(3):221-225
Handedness is a human behavioural phenotype that appears to be congenital, and is often assumed to be inherited, but for which the developmental origin and underlying causation(s) have been elusive. Models of the genetic basis of variation in handedness have been proposed that fit different features of the observed resemblance between relatives, but none has been decisively tested or a corresponding causative locus identified. In this study, we applied data from well-characterised individuals studied at the London Twin Research Unit. Analysis of genome-wide SNP data from 3940 twins failed to identify any locus associated with handedness at a genome-wide level of significance. The most straightforward interpretation of our analyses is that they exclude the simplest formulations of the ‘right-shift'' model of Annett and the ‘dextral/chance'' model of McManus, although more complex modifications of those models are still compatible with our observations. For polygenic effects, our study is inadequately powered to reliably detect alleles with effect sizes corresponding to an odds ratio of 1.2, but should have good power to detect effects at an odds ratio of 2 or more.  相似文献   
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