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Test Tubes (test + tubes)
Selected AbstractsAlternatives to pilot plant experiments in cheese-ripening studiesINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 4 2001Shakeel-ur-rehman Experimental studies on cheese have several objectives, from assessing the influence of the microflora and enzymes indigenous to milk to evaluating starters and adjuncts. Several studies have been undertaken to evaluate the influence of an individual ripening agent in the complex environment of cheese. Cheesemaking experiments, even on a pilot scale, are expensive and time-consuming, and when controlled bacteriological conditions are needed, pilot plant experiments are difficult to perform. Cheese curd slurries are simple models that can be prepared under sterile conditions in the laboratory and can be used as an intermediate between test tubes and cheese trials, but probably cannot replace the latter. Miniature model cheeses are similar to pilot plant cheeses and can be manufactured under sterile conditions. Several approaches to assess the role of cheese-ripening agents are reviewed in this paper. [source] Associative learning in animals: A selective review of recent topics and contribution of Japanese researchers1JAPANESE PSYCHOLOGICAL RESEARCH, Issue 3 2004SADAHIKO NAKAJIMA Abstract:, This article addressed several important topics in the field of associative learning in nonhuman animals: event contingency, associative retardation (learned helplessness and irrelevance), occasion setting, renewal of extinguished responses, acquired equivalence and distinctiveness, differential outcome effect, and retrospective inference. These topics have been studied with Pavlovian and instrumental conditioning preparations as behavioral test tubes for assessing animals' cognitive abilities. The empiric data are suggesting highly cognitive abilities of animals in event processing. This article also reviewed studies conducted by Japanese psychologists taking the modern associationists approach. Although activities of Japanese researchers in this field of research are high, they are required to make a more unique contribution to the field. [source] Glucoraphanin extraction from Cardaria draba: Part 1.JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2005Optimization of batch extraction Abstract Glucosinolates have historically been considered an anti-nutritional component of food and feed cereal crops. Large-scale protocols have been aimed at complete glucosinolate elimination from plants, rather than maximizing the recovery of any particular glucosinolate compound. Recently, glucoraphanin, an alkenyl glucosinolate, has been found to have nutritional value in terms of anti-carcinogenic behavior and hypertension relief. In this work, we report on the efficient capture of glucoraphanin from the noxious weed Cardaria draba. The effect of temperature, ethanol content in the aqueous solvent, initial solvent pH, solids loading, and contact time on both glucoraphanin and glucosinalbin recovery were examined. The optimal extraction conditions, evaluated using 0.11 dm3 stirred baffled vessels, were found to be 20% aqueous ethanol solvent at 70 °C and an initial pH value of 3, extracted at a solid to liquid ratio of 50 g dm,3 over 20 mins. The recovery achieved with the baffled vessels was up to three times greater than the glucoraphanin yield obtained using standard analytical procedures that involved the use of 8.0 × 10,3 dm3 of hot, 80% ethanol solutions in test tubes at the same solvent loading. This corresponds to 30 mg g,1 of glucoraphanin recovered from the dried C draba leaves, versus only 10 mg g,1 using the analytical method. Copyright © 2005 Society of Chemical Industry [source] Identity and Pathogenicity of Fungi Associated with Root and Crown Rot of Soft Red Winter Wheat Grown on the Upper Coastal Plain Land Resource Area of MississippiJOURNAL OF PHYTOPATHOLOGY, Issue 2 2000M. S. Gonzalez Seedling stand, disease severity and fungal incidence were determined from untreated ,Wakefield' soft red winter wheat planted on a Leeper silty clay loam in field tests conducted at the Mississippi Agricultural and Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi during the 1996,97 and 1997,98 growing seasons. Seedling stand was reduced by 40% each year in plots established with untreated seed. Cochliobolus sativus was the most frequently isolated fungus. Fusarium acuminatum, Fusarium equiseti and Fusarium solani were the most prevalent Fusarium spp. Seven other Fusarium spp. and 23 species of other fungal genera were isolated. Pathogenicity tests with three isolates each of C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora and Microdochium bolleyi were performed in test tube culture and two isolates each of C. sativus, C. spicifer, F. acuminatum, E. chlamydospora and M. bolleyi under greenhouse conditions. In test tubes and in the greenhouse, seedlings infected with isolates of C. sativus developed seedling blight, discoloration and necrosis, primarily in seminal roots and crowns. In the greenhouse, C. sativus induced lesions on the lower leaf sheath and reduced seedling height, seedling emergence, dry and fresh weight of roots and shoots. Isolates of F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora and M. bolleyi induced slight to moderate orange to light-brown discoloration of crown and seminal roots in test tubes. Cochliobolus spicifer isolates had the most pre-emergence activity, inducing black root discoloration and root pruning of wheat seedlings and reducing seedling emergence, root fresh weight and shoot dry weight. In the greenhouse, F. acuminatum reduced seedling height, seedling emergence and root and shoot dry weights. Microdochium bolleyi and E. chlamydospora reduced fresh and dry weight of roots, plant emergence and shoot dry weight. Fusarium acuminatum and C. spicifer reduced the growth rate of wheat seedlings. All fungi evaluated showed increased disease severity compared to the untreated control. The high frequency of isolation of C. sativus from crown and root tissues can be partially explained by the dry, warm conditions during the early stages of wheat seedling development in the Upper Coastal Plain Land Resource Area of Mississippi. Zusammenfassung Die Auflaufrate von Sämlingen, die Stärke des Krank-heitsbefalls sowie die Häufigkeit von Pilzarten wurden bei nicht behandelten roten Weichwinterweizen der Sorte Wakefield ermittelt, welche in einem Leeper schlammigen Tonboden an der Mississippi Agricultural & Forestry Experiment Station, Plant Science Research Center, Mississippi State University, Starkville, Mississippi in der 1996,97 und 1997,98 Saison gesät worden waren. In beiden Jahren wurde die Auflaufrate von nicht behandeltem Saatgut um 40% reduziert. Cochliobolus sativus wurde am häufigsten isoliert. Fusarium acuminatum, Fusarium equiseti und Fusarium solani waren die überwiegenden Fusarium spp. Außierdem wurden sieben weitere Fusarium spp. sowie 23 weitere Pilzarten isoliert. Pathogenitätstests mit je 3 Isolaten von C. sativus, Cochliobolus spicifer, F. acuminatum, F. solani, F. equiseti, Fusarium compactum, Embellisia chlamydospora und Microdochiumbolleyi wurden in Reagenzröhrchen durchgeführt, sowie mit je 2 Isolaten von C. sativus, C. spicifer, F. acuminatum, E. chlamydospora und M. bolleyi unter Gewächshausbedingungen. Sowohl in den Reagenzröhrchen als auch im Gewächshaus entwickelten Sämlinge, die mit C. sativus inokuliert worden waren, eine Fäule, Verfärbung sowie Nekrosis, hauptsächlich in den sekundären Wurzeln und in den Halmbasen. Unter Gewächshausbedingungen verursachte C. sativus außierdem Läsionen der unteren Blattscheide sowie eine Reduzierung des Sämlingswachstums, des Sämlingsauflaufs, des Trocken-und Frischgewichts der Wurzeln und Sprossen. Im Reagenzröhrchentest induzierten Isolate von F. acuminatum, F. solani, F. equiseti, F. compactum, E. chlamydospora und M. bolleyieine schwache bis mäßiige orange bis hell braune Verfärbung des Halmbasis und der Sekundärwurzeln. Isolate von C. spicifer besaßien die höchste Vorauflaufaktivität und induzierten eine Verschwärzung und Verkürzung der Wurzeln sowie eine Reduzierung des Sämlingsauflaufs, des Wurzelfrischgewichts sowie des Sproitrockengewichts. Unter Gewächshausbedingungen reduzierte F. acuminatum die Sämlingshöhe, die Auflaufrate sowie das Trockengewicht der Wurzeln und Sproien. Microdochium bolleyi und E. chlamydospora reduzierten das Frisch-und Trockengewicht der Wurzeln, die Auflaufrate sowie das Sproßitrockengewicht. Die Wachstumsrate der Sämlinge wurde durch F. acuminatum und C. spicifer reduziert. Alle untersuchten Pilzarten erhöhten die Befallsstärke verglichen mit der unbehandelten Kontrolle. Die hohe Isolierungsrate von C. sativus aus dem Halmbasis-und Wurzelgewebe kann zum Teil dadurch erklärt werden, dass während der Frühentwicklungsphase der Sämlinge trockene und warme Wachstumsbedingungen in diesem Gebiet herrschten. [source] Backpacking in Yosemite and Kings Canyon National Parks and Neighboring Wilderness Areas: How Safe Is the Water to Drink?JOURNAL OF TRAVEL MEDICINE, Issue 4 2008Robert W. Derlet MD Objective The objective of this study was to determine the risk of acquiring disease from popular Sierra Nevada wilderness area lakes and streams. This study examines the relative risk factors for harmful waterborne microorganisms using coliforms as an indicator. Methods Water was collected in the backcountry Yosemite and Kings Canyon National Parks and neighboring wilderness areas. A total of 72 sites from lakes or streams were selected to statistically differentiate the risk categories: (1) natural areas rarely visited by humans or domestic animals; (2) human day use,only areas; (3) high use by backpackers; (4) high use by pack animals; and (5) cattle- and sheep-grazing tracts. Water was collected in sterile test tubes and Millipore coliform samplers during the summer of 2006. Water was analyzed at the university microbiology lab, where bacteria were harvested and then subjected to analysis using standardized techniques. Statistical analysis to compare site categories was performed using Fisher's exact test. Results Coliforms were found in none of the 13 wild sites, none of the 12 day hike sites, and only 3 of 18 backpacker sites (17%). In contrast, 14 of 20 sites (70%) with pack animal traffic yielded coliforms, and all 9 sites (100%) below the cattle-grazing areas grew coliforms. Differences between backpacker versus cattle or pack areas were significant, p , 0.05. All samples grew normal aquatic bacteria. Sites below cattle grazing and pack animal use tended to have more total heterotrophic bacteria. Conclusions Alpine wilderness water below cattle areas used by pack animals is at risk for containing coliform organisms. Water from wild, day hike, or backpack areas showed far less risk for coliforms. [source] Coagulations in a water based magnetic fluid under magnetic fieldPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 12 2004Y. Matsuno Abstract The paper deals with the coagulations of magnetic solid particles in a water based magnetic fluid under magnetic field. The coagulations can be detected by measuring the magnetization of supernatant fluid of magnetic fluid in test tubes under magnetic field. As the coagulations increase , the magnetization of supernatant fluid decreases due to the sedimentation of coagulations. So the more the coagulations, the lower the magnetization of supernatant fluid. Moreover, when test tubes are centrifuged before magnetization measurement, the sedimentation of coagulations is accelerated and the magnetization becomes lower and the detection of coagulations becomes easier. The test results show that latent coagulations can be detected by means of centrifuging, which can not be found out without it. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Epidermal transpiration, ultrastructural characteristics and net photosynthesis of white spruce somatic seedlings in response to in vitro acclimatizationPHYSIOLOGIA PLANTARUM, Issue 4 2003Mohammed S. Lamhamedi Mortality of transplanted somatic seedlings at the stage of acclimatization is often high and likely due to rapid change in environmental conditions. To investigate the potential of in vitro acclimatization of somatic seedlings before soil transfer, somatic seedlings of white spruce (Picea glauca[Moench] Voss) were germinated on a liquid medium supplemented with sucrose. After 6 weeks in germination, sucrose was omitted from the medium for a supplementary 6 weeks at which time somatic seedlings were acclimatized in vitro in their germination tubes before transfer to soil. In vitro acclimatization of somatic seedlings was realized by transferring the test tubes containing the germinated somatic seedlings to the greenhouse for 9 days. During this period, the culture tube lids of acclimatized somatic seedlings were lifted progressively increasing air exchange between the tube and the greenhouse whereas, for non-acclimatized somatic seedlings the culture tubes were maintained closed during in vitro acclimatization. In vitro acclimatized somatic seedlings had higher asymptotic net photosynthesis (Pn) at light saturation than non-acclimatized seedlings (6 versus 4.5 µmol m,2 s,1). At the end of the in vitro acclimatization period, a lower rate of epidermal transpiration was also observed for acclimatized somatic seedlings (3.85 versus 4.75% h,1). Microscopic observations showed that starch granules were more abundant in needles of acclimatized somatic seedlings than in non-acclimatized somatic seedlings, probably as a result of their greater photosynthetic capacity. Needles from acclimatized somatic seedlings also showed more epicuticular wax projections than needles from non-acclimatized somatic seedlings. These structural changes may help somatic seedlings to restrict epidermal water loss and stomatal aperture. [source] A comparative study of sanitary napkins and absorbent nappy pads for urine output measurement in neonatesACTA PAEDIATRICA, Issue 6 2009Sourabh Dutta Abstract Aim: To compare sanitary napkins and absorbent nappy pads (ANP) for urine output (UO) measurement. Methods: Phase 1: Freshly passed neonatal urine (5, 10 and 15 mL) was poured onto preweighed sanitary napkins or ANP, which were juxtaposed to the genital area of manikins placed in incubators/warmers and weighed at ½, 1, 2, 4, 5 and 6 hr. Outcome was percentage weight change from baseline. Phase 2: Five very low birth weight boys in incubators had UO measurement by test tubes. A sanitary napkin or ANP was co-applied with the test tube for 4 h each. Urine collected in the test tube was measured and poured on the device, which was reapplied. Weight and wetness were checked. Results: Phase 1: Mean urine loss was 8.35, 13.8, 20.1, 25.2, 33.1, 38.7 and 42.6% at ½, 1, 2, 3, 4, 5 and 6 h, respectively (repeated measures ANOVA [RM-ANOVA], p < 0.001). Loss was higher with ANP than sanitary napkins (32.1% vs. 13.4%, two-way RM-ANOVA, p = 0.001). There was less loss in incubators versus radiant warmers at 6 h (p = 0.09). Phase 2: There was 12.1 and 26% deficit with sanitary napkin and ANP, respectively. Wetness was felt in one and four cases, respectively. Conclusion: Urinary losses are less from sanitary napkins than ANPs. [source] | ||||||||||||||||