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91.
A DNA region of Torulaspora delbrueckii containing the HIS3 gene: sequence, gene order and evolution
We cloned a genomic DNA fragment of the yeast Torulaspora delbrueckii by complementation of a Saccharomyces cerevisiae his3 mutant strain. DNA sequence analysis revealed that the fragment contained two complete ORFs, which share a high similarity with S. cerevisiae His3p and Mrp51p, respectively. The cloned TdHIS3 gene fully complemented the his3 mutation of S. cerevisiae, confirming that it encodes for the imidazoleglycerol-phosphate dehydrate of T. delbrueckii. Two additional ORFs, with a high homology to S. cerevisiae PET56 and DED1 genes, were mapped upstream and downstream from TdHIS3 and TdMRP51, respectively. This genetic organization is analogous to that previously found in Saccharomyces kluyveri and Zygosaccharomyces rouxii. The evolutionary significance of gene order in this chromosomal region is analysed and discussed. 相似文献
92.
Polymer Nanoparticles Encased in a Cyclodextrin Complex Shell for Potential Site‐ and Sequence‐Specific Drug Release
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Guillermo U. Ruiz‐Esparza Suhong Wu Victor Segura‐Ibarra Francisca E. Cara Kurt W. Evans Miljan Milosevic Arturas Ziemys Milos Kojic Funda Meric‐Bernstam Mauro Ferrari Elvin Blanco 《Advanced functional materials》2014,24(30):4753-4761
Time‐staggered combination chemotherapy strategies show immense potential in cell culture systems, but fail to successfully translate clinically due to different routes of administration and disparate formulation parameters that preclude a specific order of drug presentation. A novel platform consisting of drug‐containing PLGA polymer nanoparticles, stably fashioned with a shell composed of drug complexed with cationic cyclodextrin, capable of releasing drugs time‐ and sequence‐specifically within tumors is designed. Morphological examination of nanoparticles measuring 150 nm highlight stable and distinct compartmentalization of model drugs, rhodamine and bodipy, within the core and shell, respectively. Sequential release is observed in vitro, owing to cyclodextrin shell displacement and subsequent sustained release of core‐loaded drug, kinetics preserved in breast cancer cells following internalization. Importantly, time‐staggered release is corroborated in a murine breast cancer model following intravenous administration. Precise control of drug release order, site‐specifically, potentially opens novel avenues in polychemotherapy for synergy and chemosensitization strategies. 相似文献
93.
Francisca Randez-Gil Amalia Blasco Jose Antonio Prieto Pascual Sanz 《Yeast (Chichester, England)》1995,11(13):1233-1240
Saccharomyces cerevisiae contains two genes (DOGR1 and DOGR2) that are able to confer 2-deoxyglucose resistance when they are overexpressed. These genes are very similar, sharing 92% identity at the protein level. They code for two isoenzymes with 2-deoxyglucose-6 phosphate (2-DOG-6P) phosphatase activity. These enzymes have been purified and characterized. DogR1p shows an optimum pH of 6, an optimum temperature of 30°C and a KM on 2-DOG-6P of 17 mM. DogR2p shows a similar optimum pH, but the optimum temperature is 40°C and it exhibits a KM on 2-DOG-6P of 41 mM. Both enzymes require 10 mM-MgCl2 for maximal activity and they are inhibited by inorganic phosphate. 相似文献
94.
Fluoride intercalation/deintercalation cycles on commercially available high purity graphite electrodes leads to powder formation and electrode damage. Formation of polypyrrole films of optimum thickness by potential cycling on the graphite surface before fluoride intercalation leads to good mechanical stability to the electrode during intercalation/deintercalation cycles. The intercalation potential shifts by 200 mV in the positive direction. The intercalation and deintercalation charges (Q
a, Q
c) also decrease slightly. However the charge recovery ratio (Q
c/Q
a) improves significantly. Since the polypyrrole layer is compact on the graphite surface, the present study indicates that the film offers mechanical stability to the graphite film without affecting the electronic conductivity of the surface. F– ion transport through the film also occurs with a small overvoltage. 相似文献
95.
Francisca H.E. Wouda Paul van Beek Jack G.A. J. van der Vorst Heiko Tacke 《OR Spectrum》2002,24(4):449-465
Between 1995 and 1998 Nutricia acquired a number of dairy companies in Hungary. Each of these companies produced a wide variety
of products for its regional market. Although alterations had been made to the production system in the last few years, production
and transportation costs were still substantial. This paper presents a research study with regard to the optimisation of the
supply network of Nutricia Hungary using a mixed-integer linear programming model. Focussing on consolidation and product
specialisation of plants the objective was to find the optimal number of plants, their locations and the allocation of the
product portfolio to these plants, when minimizing the sum of production and transportation costs. The model is in line with
traditional location/allocation models, with a modification concerning inter-transportation of semi-finished products between
plants. The production costs used in this model are based on a Green field situation, taking into account new and more advanced
technologies available today. The model is used by the Nutricia Dairy and Drinks Group as a decision supporting tool.
Correspondence to: F. H. E. Wouda 相似文献
96.
Chukwujindu M. A. Iwegbue Henry Agadaga Francisca I. Bassey Loretta C. Overah Godswill O. Tesi Godwin E. Nwajei 《International Journal of Food Properties》2013,16(10):2124-2133
Concentrations and profiles of polycyclic aromatic hydrocarbons were determined in some popular commercial brands of tea-, coffee-, and cocoa-based food drinks in Nigeria by gas chromatograph-flame ionization after hexane/dichloromethane extraction and clean up. The concentrations of the ∑16 Polycyclic aromatic hydrocarbons in these products ranged from 5.2–913.1, 38.7–593.1, and 38.0–1406.4 μg kg?1 for tea-, coffee-, and cocoa-based food drinks, respectively. The polycyclic aromatic hydrocarbon profiles indicate the dominance of three and four rings PAHs in these food items. The concentrations of the European Food Safety Authority (EFSA) eight carcinogenic polycyclic aromatic hydrocarbons ranged from nd–218.9, nd–102.9, and nd–1248.5 μg kg?1 for tea-, coffee-, and cocoa-based food drinks, respectively. 相似文献
97.
Ana Lúcia Fernandes Pereira Francisca Diva Lima Almeida Ana Laura Tibério de Jesus José Maria Correia da Costa Sueli Rodrigues 《Food and Bioprocess Technology》2013,6(11):3155-3165
The stability of nonfermented cashew apple juice (control) and the fermented juice with Lactobacillus casei NRRL B-442 (sweetened and nonsweetened samples) was investigated along the storage at 4 °C for 42 days. The viability of the probiotic bacteria, sugars, lactic acid, and vitamin C content besides color, antioxidant activity, enzyme activity, and sensory characteristics of probiotic cashew apple juice was evaluated. It was observed that viable cell counts increased in the probiotic cashew apple containing sucrose (8 % w/v) along the storage period. Viable cell counts were always higher than 8.00 Log CFU/ml throughout the storage period. Ascorbic acid loss was higher in the nonfermented juice (40 %) compared to the fermented juice (23 %). The same behavior was observed for antioxidant activity and total polyphenolic compounds content, conferring nutritional benefits to this functional food. Browning reactions and nutritional breakdown caused by enzymes were minimized in the fermented samples during storage. In the fermented sample, higher reduction (>70 %) in the polyphenol oxidase enzyme activity was observed. During storage, the increase in the chroma values from 3.2 to 5.0 indicated that the yellow color became more vivid. Sensory analysis of the fermented cashew apple juice revealed that the product was well-accepted, with acceptance percentages above 80 % for the sweetened juice at the end of the storage period. 相似文献
98.
Miguel A. Santajuana Rosalia Rementeria Matthias Kuntz Jose A. Jimenez Francisca G. Caballero Carlos Garcia-Mateo 《Metallurgical and Materials Transactions A》2018,49(6):2026-2036
The thermal stability of nanobainitic structures obtained by heat treating two different high-carbon high-silicon steels at temperatures between 200 °C and 600 °C has been investigated by means of three complementary techniques, i.e., field emission gun-scanning electron microscopy, X-ray diffraction, and high-resolution dilatometry. Three main stages have been established, each of them characterized by a distinctive microstructure. Furthermore, the nanocrystalline structure generated by the bainite reaction confers the steel with an extraordinary tempering resistance. 相似文献
99.
Francisca A Ansah Maria L Amodio Giancarlo Colelli 《Journal of the science of food and agriculture》2018,98(10):3614-3626
There is a rising demand for fresh‐cut convenience products with high quality and nutritional standards that needs to be met by the fresh‐cut industry. It is well known that harvest and postharvest handling of fresh produce has a paramount impact on its quality and storage, although most of the existing literature has focused on these impacts related only to fresh produce that is destined for the final consumers. Indeed, current harvest methods and postharvest technologies have improved fruit and vegetable handling and distribution processes by slowing down physiological processes and senescence. Nonetheless, these technologies and methods may influence the quality of fresh produce as raw material for fresh‐cut processing as a result of the dynamic responses of fresh produce to handling procedures and treatments. Here, we review the existing literature on the challenges facing the fresh‐cut industry, focusing on the impact of harvest, maturity, and handling of fruit and vegetables on the quality of raw materials, as well as the implications for fresh‐cut products. The review also highlights areas for further research with the aim of enhancing the sensorial, nutritional and biochemical quality of such products. © 2018 Society of Chemical Industry 相似文献
100.
Influence of deficit irrigation and crop load on the yield and fruit quality in Wonderful and Mollar de Elche pomegranates
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