Impact of guar and xanthan gums on proofing and calorimetric parameters of frozen bread dough   总被引：2，自引：0，他引：2  

Tatiana Guinoza Matuda  Sylvie Chevallier  Pedro de Alcntara Pessa Filho  Alain LeBail  Carmen Cecília Tadini 《Journal of Cereal Science》2008,48(3):741-746

The influence of guar and xanthan gum and their combined use on dough proofing rate and its calorimetric properties was investigated. Fusion enthalpy, which is related to the amount of frozen water, was influenced by frozen dough formulation and storage time; specifically gum addition reduced the fusion enthalpy in comparison to control formulation, 76.9 J/g for formulation with both gums and 81.2 J/g for control, at 28th day. Other calorimetric parameters, such as T_g and freezable water amount, were also influenced by frozen storage time. For all formulations, proofing rate of dough after freezing, frozen storage time and thawing, decreased in comparison to non-frozen dough, indicating that the freezing process itself was more detrimental to the proofing rate than storage time. For all formulations, the mean value of proofing rate was 2.97 ± 0.24 cm³ min⁻¹ per 100 g of non-frozen dough and 2.22 ± 0.12 cm³ min⁻¹ per 100 g of frozen dough. Also the proofing rate of non-frozen dough with xanthan gum decreased significantly in relation to dough without gums and dough with only guar gum. Optical microscopy analyses showed that the gas cell production after frozen storage period was reduced, which is in agreement with the proofing rate results.  相似文献   

Importance of the life cycle in sympatric host race formation and speciation of pathogens     

Giraud T  Villaréal LM  Austerlitz F  Le Gac M  Lavigne C 《Phytopathology》2006,96(3):280-287

ABSTRACT Numerous morphological species of pathogenic fungi have been shown to actually encompass several genetically isolated lineages, often specialized on different hosts and, thus, constituting host races or sibling species. In this article, we explore theoretically the importance of some aspects of the life cycle on the conditions of sympatric divergence of host races, particularly in fungal plant pathogens. Because the life cycles classically modeled by theoreticians of sympatric speciation correspond to those of free-living animals, sympatric divergence of host races requires the evolution of active assortative mating or of active host preference if mating takes place on the hosts. With some particular life cycles with restricted dispersal between selection on the host and mating, we show that divergence can occur in sympatry and lead to host race formation, or even speciation, by a mere process of specialization, with strong divergent adaptive selection. Neither active assortative mating nor active habitat choice is required in these cases, and this may explain why the phylo-genetic species concept seems more appropriate than the biological species concept in these organisms.  相似文献   

Effluents from Anaerobic Digestion of Organic Wastes: Treatment by Chemical and Electrochemical Processes     

Annabel Fernandes  Tatiana Jesus  Rodrigo Silva  Maria José Pacheco  Lurdes Ciríaco  Ana Lopes 《Water, air, and soil pollution》2017,228(11):441

The treatment of effluent from anaerobic digestion of organic wastes was carried out using chemical and electrochemical processes, namely, chemical coagulation (CC) with lime, electrocoagulation (EC) with iron consumable electrodes, and electrochemical oxidation (EO) with a boron-doped diamond anode, at different experimental conditions. In the CC assays, the highest chemical oxygen demand (COD) removal, 50%, was achieved for a lime concentration of 70 g L^?1 after 2 h experiment. Under the experimental conditions studied, EC promoted COD removals of 80% after 5 h and EO led to COD removals of 43% after 6 h electrolysis, being this last removal increased to 60% when chloride was added to the effluent. A combined EC+EO treatment was also performed, utilizing the most favorable experimental conditions obtained in the individual processes, and global removals of 95% in COD and 44% in ammonia nitrogen were attained after 5 h of EC followed by 6 h of EO. These results proved that the combined process can be an efficient alternative in the treatment of effluents from anaerobic digestion of organic wastes with the characteristics of the studied effluent.  相似文献   

Lignin deposition during earlywood and latewood formation in Scots pine stems     

Galina F. Antonova  Tamara N. Varaksina  Tatiana V. Zheleznichenko  Victoria V. Stasova 《Wood Science and Technology》2014,48(5):919-936

Lignin deposition at consecutive secondary wall thickening stages of early and late xylem cells during annual ring wood formation in Scots pine (Pinus sylvestris L.) stems was studied. Lignin patterns, isolated by thioglycolic acid method, consisted of alcohol-soluble (LTGA-I) and alkali-soluble (LTGA-II) fractions. The sum of two fractions, being the total lignin content, gradually increased in the course of lignification. However, the increments of lignin amount at each development stage of early and late tracheids were different. The intensity of lignin deposition increased in the course of earlywood tracheid maturation and decreased toward the end of latewood cell differentiation. The deposition of two lignin fractions in each layer of forming wood also occurred oppositely. The increment of LTGA-I descended, whereas that of LTGA-II increased from the beginning to the end of early xylem lignification. In contrast, LTGA-I increment dropped, whereas LTGA-II rose during late xylem lignification. Gel permeation chromatography showed that the lignins, formed at the beginning of lignification, were more homogeneous and had higher molecular weight compared with the lignins at the end of cell differentiation. Besides, the content of cellulose, estimated as the residue after lignin isolation, and of cell wall substances, presented as cell wall cross-section areas, at consecutive maturation stages of early and late xylem cells have been found to be different. The data show that lignin deposition occurred in different conditions and with opposite dynamics during early and late xylem formation.  相似文献   

Are <Emphasis Type="Italic">Lotus creticus</Emphasis> and <Emphasis Type="Italic">Lotus cytisoides</Emphasis> (Leguminosae) closely related species? Evidence from nuclear ribosomal ITS sequence data     

Graeme Sandral  Galina V. Degtjareva  Tatiana E. Kramina  Dmitry D. Sokoloff  Tahir H. Samigullin  Steve Hughes  Carmen M. Valiejo-Roman 《Genetic Resources and Crop Evolution》2010,57(4):501-514

Lotus creticus is a potentially important perennial legume for soil management in the Mediterranean climate. This plant is in focus of experimental research in different countries. The so-called Lotus creticus group is taxonomically problematic. Although some authors consider all members of the group as a single variable species, others segregate several species distinct from L. creticus, especially L. cytisoides. Recent morphological studies suggested that L. creticus and L. cytisoides are taxonomically distinct at specific level and not even closely related to each other. Two molecular phylogenetic studies published so far and based on one accession of L. creticus each gave conflicting results on relationships of this species. In this paper, sequences of nuclear ribosomal ITS (nrITS) are produced from multiple accessions of both L. creticus and L. cytisoides. Taxonomic identity of each accession has been tested using morphology. The new nrITS sequences are inserted in a data matrix containing a representative set of Lotus species covering all the geographical range and all major taxonomic groups of Lotus. Phylogenetic analysis of nrITS sequence data showed that L. creticus is related to L. assakensis and other species of the section Pedrosia while L. cytisoides is related to L. longisiliquosus and other species of the section Lotea. These results are important for establishing future germplasm collection, breeding and selection programs of perennial Lotus species.  相似文献   

Prevalence of <Emphasis Type="Italic">Toxoplasma gondii</Emphasis> and <Emphasis Type="Italic">Neospora caninum</Emphasis> infections in sheep from Federal District,central region of Brazil   总被引：1，自引：1，他引：0  

Ueno TE  Gonçalves VS  Heinemann MB  Dilli TL  Akimoto BM  de Souza SL  Gennari SM  Soares RM 《Tropical animal health and production》2009,41(4):547-552

Serum samples from 1028 sheep were collected from 32 herds within Federal District, in the central region of Brazil. The samples were examined by indirect fluorescent antibody test (IFAT) using sera diluted 1:64 and 1:50 as cut-off values for the detection of antibodies against Toxoplasma gondii and Neospora caninum, respectively. The observed prevalence for T. gondii infection was 38.22% (26.81%<CI 0.95<49.62%), and the titers ranged from 64 to 65536. The observed prevalence for N. caninum infection was 8.81% (7.08%<CI 0.95<10.53%). The titers ranged from 50 to 51200. The reactant sera to both pathogens corresponded to 4.67% of the samples. The risk factors were not determined because of the absence of negative herds for T. gondii and the high proportion of positive herds for N. caninum (87.50%). The prevalence for T. gondii infection was significantly higher among males than in females. The present work is the first report on seroprevalence of T. gondii and N. caninum in sheep from Federal District and shows that infection by both parasites is widespread in the ovine population from this region.  相似文献   

Evaluation of the Perkins^® handheld applanation tonometer in the measurement of intraocular pressure in dogs and cats     

Silvia Franco Andrade  Tatiana Cremonezi†  Cristiane Aparecida Miranda Zachi†  Caroline Ferreira Lonchiati†  Juliana Dalarrosa Amatuzzi†  Keila Priscilla Sakamoto†  Paulo Augusto de Arruda Mello‡ 《Veterinary ophthalmology》2009,12(5):277-284

Objective  To evaluate and to validate the accuracy of the Perkins^® handheld applanation tonometer in the measurement of IOP in dogs and cats.
Animals  Twenty eyes from 10 dogs and 10 cats immediately after sacrifice were used for the postmortem study and 20 eyes from 10 clinically normal and anesthetized dogs and cats were used for the in vivo study. Both eyes of 20 conscious dogs and cats were also evaluated.
Procedure  Readings of IOP postmortem and in vivo were taken using manometry (measured with a mercury column manometer) and tonometry (measured with a Perkins^® handheld applanation tonometer). The IOP measurement with Perkins^® tonometer in anesthetized and conscious dogs and cats was accomplished by instillation of proxymetacaine 0.5% and of 1% fluorescein eye drops.
Results  The correlation coefficient ( r ²) between the manometry and the Perkins^® tonometer were 0.982 (dogs) and 0.988 (cats), and the corresponding linear regression equation were y  = 0.0893 x  + 0.1105 (dogs) and y  = 0.0899 x  + 0.1145 (cats) in the postmortem study. The mean IOP readings with the Perkins^® tonometer after calibration curve correction were 14.9 ± 1.6 mmHg (range 12.2–17.2 mmHg) in conscious dogs, and were 15.1 ± 1.7 mmHg (range 12.1–18.7 mmHg) in conscious cats.
Conclusion  There was an excellent correlation between the IOP values obtained from direct ocular manometry and the Perkins^® tonometer in dogs and cats. The Perkins^® handheld tonometer could be in the future a new alternative for the diagnosis of glaucoma in veterinary ophthalmology.  相似文献   

Comprehensive study of Pb (II) speciation in soil by X-ray absorption spectroscopy (XANES and EXAFS) and sequential fractionation     

Dina G. Nevidomskaya  Tatiana M. Minkina  Alexander V. Soldatov  Victoria A. Shuvaeva  Yan V. Zubavichus  Yulia S. Podkovyrina 《Journal of Soils and Sediments》2016,16(4):1183-1192

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Factors affecting taste scores of early season seedless table grape cv. Mystery and Prime.     

Lilian Sonego  Susan Lurie  Yohanan Zuthi  Tatiana Kaplonov  Ruth Ben-Arie  Itzhak Kosto 《Journal of agricultural and food chemistry》2002,50(3):544-548

Table grapes of cv. Mystery and Prime were harvested from 10 farms in two growing areas of Israel over two seasons. The grapes were separated on the basis of sucrose solutions from 12 to 18%; soluble solids content (SSC), titratable acidity (TA), and pH were determined; and taste tests were conducted. SSC gave the best correlation with taste tests, and multiple regression of SSC, TA, and pH improved the correlation. There were both seasonal and regional differences in the measured maturity parameters. Lower TA and higher pH were found in grapes from the Jordan Valley. Volatiles were predominantly C(6) compounds hexanal and 2-hexanal, contributing a fresh aroma to the grapes. It is concluded that Mystery and Prime grapes have good organoleptic quality if harvested at SSC levels of >14%.  相似文献   

Evaluating inputs of heavy metal contaminants and phosphorus to lake ontario from Hamilton Harbour     

Tatiana Mayer  Philip G. Manning 《Water, air, and soil pollution》1991,59(3-4):281-298

The presence and the extent of the plume of Hamilton Harbour water extending into Lake Ontario was determined in order to assess the importance of metal contaminant transport from Hamilton Harbour into Lake Ontario. Industrially derived Fe compounds, wustite and hematite, were used as plume tracking parameters. Wustite, particularly, proved to be a good tracer of the plume. Annual loadings of particulate heavy metals to Lake Ontario were calculated using the concentrations of heavy metals in suspended solids from the connecting Burlington Canal, Hamilton Harbour and western Lake Ontario. Annual loadings of heavy metals to lake Ontario are ～266 × 10³ kg Fe, 9.33 × 10³ kg Zn, 1356 kg Pb, 273 kg Cu, 8.7 kg Cd. The relative contribution of the total metal load from Hamilton Harbour to Lake Ontario is negligible when compared to the load from the Niagara River. Lake-harbour water exchange and the high Fe concentrations in benthic sediments of Hamilton Harbour increase P retention in the harbour sediments, thus are beneficial to water quality in Hamilton Harbour.  相似文献