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The Neurospora crassa Asm-1+ (ascospore maturation 1) gene encodes an abundant nucleus-localized protein required for formation of female structures and for ascospore maturation. Deletion mutants of Asm-1+ are "ascus-dominant," i.e., when crossed to wild type, neither Asm-1+ nor Asm-1 delta spores mature. To explain this behavior, we considered three models: an effect of reduced dosage of the gene product, failure of internuclear communication, and failure of transvection (regulation dependent on pairing of alleles). We found that for proper regulation of subsequent sexual sporulation, Asm-1+ must be in proximity, probably paired, to its allelic counterpart in the zygote: i.e., transvection must occur. Disruption of pairing causes failure of ascospore progeny to mature. Transvection in Neurospora, unlike in Drosophila, occurs immediately before meiosis, and can be demonstrated between wild-type alleles.  相似文献   
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In this paper, we present the building of various language resources for a multi-engine bi-directional English-Filipino Machine Translation (MT) system. Since linguistics information on Philippine languages are available, but as of yet, the focus has been on theoretical linguistics and little is done on the computational aspects of these languages, attempts are reported here on the manual construction of these language resources such as the grammar, lexicon, morphological information, and the corpora which were literally built from almost non-existent digital forms. Due to the inherent difficulties of manual construction, we also discuss our experiments on various technologies for automatic extraction of these resources to handle the intricacies of the Filipino language, designed with the intention of using them for the MT system. To implement the different MT engines and to ensure the improvement of translation quality, other language tools (such as the morphological analyzer and generator, and the part of speech tagger) were developed.  相似文献   
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ABSTRACT

A non-hazardous groundwater treatment waste (GWTW) was examined as a low-cost sorbent for Pb(II) and Cu(II) ions. The content of the dominant elements in GWTW was as follows: 78% Fe2O3, 7.4% P2O5, 7.4% CaO and 5.2% SiO2. The removal of Pb(II) and Cu(II) was fast, and more than 67–95% of ions were accumulated by GWTW during the first 3 min. The sorption capacity of GWTW depends on solution pH, concentration and temperature. Equilibrium data fitted well with Langmuir–Freundlich and Langmuir-partition models. The inherently formed nano-adsorbent could be utilized for the treatment of water contaminated with Pb(II) and Cu(II) ions.  相似文献   
5.
A ternary ordered variant of the skutterudite structure, the Co4Sn6Se6 compound, was prepared. Polycrystalline samples were prepared by a modified ceramic method. The electrical conductivity, the Seebeck coefficient and the thermal conductivity were measured over a temperature range of 300–800 K. The undoped Co4Sn6Se6 compound was of p-type electrical conductivity and had a band gap E g of approximately 0.6 eV. The influence of transition metal (Ni and Ru) doping on the thermoelectric properties was studied. While the thermal conductivity was significantly lowered both for the undoped Co4Sn6Se6 compound and for the doped compounds, as compared with the Co4Sb12 binary skutterudite, the calculated ZT values were improved only slightly.  相似文献   
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Meat contaminating bacteria may be the direct cause of foodborne diseases and represent a potential cause for the drug resistance of human pathogenic agents. The prevalence and resistance to 17 antimicrobial drugs of isolates of selected bacterial species were investigated in 70 swabs of beef carcasses and 70 subsequent samples of beef meat. Molecular techniques (coagulase gene typing Staphylococcus aureus and original gene typing Escherichia coli) were used in the differentiation of isolates. Carcasses were already contaminated after evisceration, least frequently with S. aureus strains (7.5% of samples), most frequently with coagulase-negative staphylococci strains (52.2% of samples). During carcass processing, contamination with resistant or polyresistant strains of S. aureus and E. coli significantly increased (P<0.01). Gene typing isolates of S. aureus and E. coli indicated that the strains probably originated in the processing plant.  相似文献   
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Titanium and zirconium dioxide coatings were deposited on optical fibres by the sol-gel procedure. The thickness of the layers on fibres was established by measurement of the intensity of characteristic X-rays by an electron microprobe analyser. The accuracy of the measurements was verified on broken layers by scanning electron microscopy. Also determined were the thicknesses of similar layers deposited on flat silica substrates with an ellipsometer and stylus surfometer as well as from reflectivity spectra and from specular total reflection of X-rays. The densities of TiO2 and ZrO2 layers on silica glass slabs were determined by X-ray total reflection. Values of 3.16 ± 0.02 and 4.69 ± 0.03 gm cm–2 were found for titania and zirconia, respectively. The crystallinity of layers on silica plates was investigated by Raman spectroscopy. The thicknesses of coatings prepared by the dipping technique were related to the withdrawal speed. Equations for Newtonian and non-Newtonian fluids were tested and compared. A pseudo-plastic behaviour was suggested for all the solutions used in the experiments.  相似文献   
10.
The aim of this study was to investigate the shelf-life of commercial sliced dry fermented sausage during storage at different temperatures. Different laminate composition was used for vacuum and nitrogen (100% N2) packaging. The microbiological, physico-chemical and sensory parameters were analysed during 120 days storage at 4, 22 and 37 °C. Packaging materials were analysed for their barrier characteristic (oxygen permeability).  相似文献   
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