Science.gov

Sample records for germination test applied

  1. Germination and root elongation bioassays in six different plant species for testing Ni contamination in soil.

    PubMed

    Visioli, Giovanna; Conti, Federica D; Gardi, Ciro; Menta, Cristina

    2014-04-01

    In vitro short-term chronic phytotoxicity germination and root elongation test were applied to test the effects of nickel (Ni) in seed germination and root elongation in six plants species: Cucumis sativus (Cucurbitaceae), Lepidium sativum and Brassica nigra (Brassicaceae), Trifolium alexandrinum and Medicago sativa (Fabaceae), Phacelia tanacetifolia (Boraginaceae). A naturally Ni rich soil was used to compare the results obtained. Unlike root elongation, germination was not affected by Ni in any of the six species tested. EC50 values, calculated on the root elongation, showed that Ni toxicity decreases in the following order: P. tanacetifolia > B. nigra > C. sativus > L. sativum > M. sativa > T. alexandrinum. The test conducted using soil elutriate revealed a significantly lower effect in both seed germination and root elongation when compared to the results obtained using untreated soil. Conversely, the test performed on soil confirmed the high sensitivity of C. sativus, P. tanacetifolia and L. sativum to Ni. PMID:24288040

  2. Establishing Germination Testing as a Priority in a Genebank

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2002, the Plant Genetic Resources Conservation Unit (PGRCU), Griffin, GA, established a program to test the germination of plant genetic resources maintained in the on-site collection. Prior to this date, regeneration priorities were based on seed age and quantity of seed available for distribut...

  3. STRESS GERMINATION RING TEST WITH IIRB AND FIELD VALIDATION IN MICHIGAN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This test was conducted to validate field emergence on lines selected by European breeding companies for a ‘ring test’ to evaluate the water germination stress test developed at East Lansing for predicting relative field emergence. Water and hydrogen peroxide germination tests were conducted prior t...

  4. SEED GERMINATION AND ROOT ELONGATION TOXICITY TESTS IN HAZARDOUS WASTE SITE EVALUATION: METHODS DEVELOPMENT AND APPLICATIONS

    EPA Science Inventory

    Seed germination tests measure soil toxicity directly, while root elongation tests consider the indirect effects of water-soluble constituents which may be present in site-samples. n the seed germination toxicity test, site-soil is mixed with a reference soil to yield exposure co...

  5. Are cactus growth forms related to germination responses to light? A test using Echinopsis species

    NASA Astrophysics Data System (ADS)

    Ortega-Baes, Pablo; Aparicio-González, Mónica; Galíndez, Guadalupe; del Fueyo, Patricia; Sühring, Silvia; Rojas-Aréchiga, Mariana

    2010-05-01

    In this study, we investigated the effect of light regimen (white light vs. darkness) on the germination of 12 species of the Echinopsis genus (tribe Trichocereeae, Cactaceae). This genus presents a variety of growth forms and relatively small and uniform seed size. These traits allowed us to test, within the same linage and removing seed mass effect, the hypothesis that the germination response to light (indifferent to light or positive photoblastic) is related to growth form. Our results reject this hypothesis since no seeds germinated in darkness, so all of the species can be classified as being positively photoblastic. The proportion of seed germination with white light was significantly different among cactus growth forms. Columnar cacti (arborescent, creeping and short) showed a greater proportion of seed germination than barrel and globose cacti. The germination rate differed among growth forms and species. At constant temperatures, creeping columnar cacti presented a significantly higher germination rate than the other growth forms. With alternating temperatures, columnar cacti showed higher germination rates than the other growth forms. The low proportion of seeds that germinated for some species indicates that they show seed dormancy. Our results suggest that germination responses to light in the cactus family could be related to seed mass and phylogenetic constraints.

  6. Inference of sigma factor controlled networks by using numerical modeling applied to microarray time series data of the germinating prokaryote

    PubMed Central

    Strakova, Eva; Zikova, Alice; Vohradsky, Jiri

    2014-01-01

    A computational model of gene expression was applied to a novel test set of microarray time series measurements to reveal regulatory interactions between transcriptional regulators represented by 45 sigma factors and the genes expressed during germination of a prokaryote Streptomyces coelicolor. Using microarrays, the first 5.5 h of the process was recorded in 13 time points, which provided a database of gene expression time series on genome-wide scale. The computational modeling of the kinetic relations between the sigma factors, individual genes and genes clustered according to the similarity of their expression kinetics identified kinetically plausible sigma factor-controlled networks. Using genome sequence annotations, functional groups of genes that were predominantly controlled by specific sigma factors were identified. Using external binding data complementing the modeling approach, specific genes involved in the control of the studied process were identified and their function suggested. PMID:24157841

  7. Testing nucleoside analogues as inhibitors of Bacillus anthracis spore germination in vitro and in macrophage cell culture.

    PubMed

    Alvarez, Zadkiel; Lee, Kyungae; Abel-Santos, Ernesto

    2010-12-01

    Bacillus anthracis, the etiological agent of anthrax, has a dormant stage in its life cycle known as the endospore. When conditions become favorable, spores germinate and transform into vegetative bacteria. In inhalational anthrax, the most fatal manifestation of the disease, spores enter the organism through the respiratory tract and germinate in phagosomes of alveolar macrophages. Germinated cells can then produce toxins and establish infection. Thus, germination is a crucial step for the initiation of pathogenesis. B. anthracis spore germination is activated by a wide variety of amino acids and purine nucleosides. Inosine and l-alanine are the two most potent nutrient germinants in vitro. Recent studies have shown that germination can be hindered by isomers or structural analogues of germinants. 6-Thioguanosine (6-TG), a guanosine analogue, is able to inhibit germination and prevent B. anthracis toxin-mediated necrosis in murine macrophages. In this study, we screened 46 different nucleoside analogues as activators or inhibitors of B. anthracis spore germination in vitro. These compounds were also tested for their ability to protect the macrophage cell line J774a.1 from B. anthracis cytotoxicity. Structure-activity relationship analysis of activators and inhibitors clarified the binding mechanisms of nucleosides to B. anthracis spores. In contrast, no structure-activity relationships were apparent for compounds that protected macrophages from B. anthracis-mediated killing. However, multiple inhibitors additively protected macrophages from B. anthracis. PMID:20921305

  8. Germination and emergence tests for predicting switchgrass field establishment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of switchgrass (Panicum virgatum L.) seed quality tests on field establishment has not been addressed. Our objective was to evaluate the ability of seed quality tests to predict field establishment. Standard Association of Official Seed Analysts (AOSA) tests are based on the percentage of...

  9. Identification of irradiated wheat by germination test, DNA comet assay and electron spin resonance

    NASA Astrophysics Data System (ADS)

    Barros, Adilson C.; Freund, Maria Teresa L.; Villavicencio, Ana Lúcia C. H.; Delincée, Henry; Arthur, Valter

    2002-03-01

    In several countries, there has been an increase in the use of radiation for food processing thus improving the quality and sanitary conditions, inhibiting pathogenic microorganisms, delaying the natural aging process and so extending product lifetime. The need to develop analytical methods to detect these irradiated products is also increasing. The goal of this research was to identify wheat irradiated using different radiation doses. Seeds were irradiated with a gamma 60Co source (Gammacell 220 GC) in the Centro de Energia Nuclear na Agricultura and the Instituto de Pesquisas Energéticas e Nucleares. Dose rate used were 1.6 and 5.8kGy/h. Applied doses were 0.0, 0.10, 0.25, 0.50, 0.75, 1.0, and 2.0kGy. After irradiation, seeds were analysed over a 6 month period. Three different detection methods were employed to determine how irradiation had modified the samples. Screening methods consisted of a germination test measuring the inhibition of shooting and rooting and analysis of DNA fragmentation. The method of electron spin resonance spectroscopy allowed a better dosimetric evaluation. These techniques make the identification of irradiated wheat with different doses possible.

  10. A Quick-Test for Biochar Effects on Seed Germination

    EPA Science Inventory

    Biochar is being globally evaluated as a soil amendment to improve soil characteristics (e.g. soil water holding, nutrient exchange, microbiology, pesticides and chemical availability) to increase crop yields. Unfortunately, there are no quick tests to determine what biochar type...

  11. Acoustic emission testing applied to tank cars

    SciTech Connect

    Stuart, R.L. )

    1989-01-01

    A major portion of the U.S. chemical and related commodities production is transported in railroad tank cars. Performance of this equipment directly impacts the economic health of the chemical industry; therefore, it is important that tank cars be properly maintained. It is important that every effort be made to minimize the chance of product release. Metallurgical defects, such as cracks and corrosion, are examples of problems that cause downtime, add cost and limit good performance. These type defects, if undetected, have potential for threatening proper product containment. In addition, defective tank cars erode good customer relationships. This issue was studied and it was concluded that an improved nondestructive testing method applied to tank cars could lead to a safer and more efficient fleet. This paper reports on a project established to extend acoustic emission (AE) testing to tank car tanks.

  12. Applying Motion Constraints Based on Test Data

    NASA Technical Reports Server (NTRS)

    Burlone, Michael

    2014-01-01

    MSC ADAMS is a simulation software that is used to analyze multibody dynamics. Using user subroutines, it is possible to apply motion constraints to the rigid bodies so that they match the motion profile collected from test data. This presentation describes the process of taking test data and passing it to ADAMS using user subroutines, and uses the Morpheus free-flight 4 test as an example of motion data used for this purpose. Morpheus is the name of a prototype lander vehicle built by NASA that serves as a test bed for various experimental technologies (see backup slides for details) MSC.ADAMS"TM" is used to play back telemetry data (vehicle orientation and position) from each test as the inputs to a 6-DoF general motion constraint (details in backup slides) The MSC.ADAMS"TM" playback simulations allow engineers to examine and analyze flight trajectory as well as observe vehicle motion from any angle and at any playback speed. This facilitates the development of robust and stable control algorithms, increasing reliability and reducing development costs of this developmental engine The simulation also incorporates a 3D model of the artificial hazard field, allowing engineers to visualize and measure performance of the developmental autonomous landing and hazard avoidance technology ADAMS is a multibody dynamics solver. It uses forces, constraints, and mass properties to numerically integrate equations of motion. The ADAMS solver will ask the motion subroutine for position, velocity, and acceleration values at various time steps. Those values must be continuous over the whole time domain. Each degree of freedom in the telemetry data can be examined separately; however, linear interpolation of the telemetry data is invalid, since there will be discontinuities in velocity and acceleration.

  13. Assessment of heavy metals phytotoxicity using seed germination and root elongation tests: a comparison of two growth substrates.

    PubMed

    Di Salvatore, M; Carafa, A M; Carratù, G

    2008-11-01

    Seed germination and root elongation test is used to evaluate hazardous waste sites and to assess toxicity of organic and inorganic compounds. Paper substrate, especially circular filter paper placed inside a Petri dish has long been used for this test. Same reports indicate that filter paper might interfere with the toxicity of inorganic substances, especially metal cations. This study evaluate toxicity of Cd, Pb, Ni, Cu on lettuce, broccoli, tomato and radish seed using two bed material: agar and filter paper. The results show that percent germination is not affected by substrates; vice versa, as for root elongation, the test in agar showed to be more sensible than that the one on filter paper. The radical growth inhibition depends on the metal, on the tested concentration and on the species; among the tested metals, cadmium was the one determining the highest toxic effects on different species and lettuce was the plant that suffered more. From the comparison, it is clearly evident the greater sensibility of the test in agar; on the other hand, the lower sensibility of the test on the filter paper might be caused by the partial and not homogeneous exposition of the root to metal cations. PMID:18768198

  14. Reliability analysis applied to structural tests

    NASA Technical Reports Server (NTRS)

    Diamond, P.; Payne, A. O.

    1972-01-01

    The application of reliability theory to predict, from structural fatigue test data, the risk of failure of a structure under service conditions because its load-carrying capability is progressively reduced by the extension of a fatigue crack, is considered. The procedure is applicable to both safe-life and fail-safe structures and, for a prescribed safety level, it will enable an inspection procedure to be planned or, if inspection is not feasible, it will evaluate the life to replacement. The theory has been further developed to cope with the case of structures with initial cracks, such as can occur in modern high-strength materials which are susceptible to the formation of small flaws during the production process. The method has been applied to a structure of high-strength steel and the results are compared with those obtained by the current life estimation procedures. This has shown that the conventional methods can be unconservative in certain cases, depending on the characteristics of the structure and the design operating conditions. The suitability of the probabilistic approach to the interpretation of the results from full-scale fatigue testing of aircraft structures is discussed and the assumptions involved are examined.

  15. Rapid bioassessment methods for assessing vegetation toxicity at the Savannah River Site - germination tests and root elongation trials

    SciTech Connect

    Specht, W.L.; Klaine, S.J.; Hook, D.D.

    1996-01-01

    Plants form the basis of all ecosystems including wetlands. Although they are the most abundant life form and are the primary producers for all other organisms, they have received the least attention when it comes to environmental matters. Higher plants have rarely been used in ecotoxicity testing and may not respond in the same manner as algae, which have been used more frequently. The introduction of hazardous waste materials into wetland areas has the potential to alter and damage the ecological processes in these ecosystems. Measuring the impact of these contaminants on higher plants is therefore important and needs further research. Higher plants are useful for detecting both herbicidal toxicity and heavy metal toxicity. For phytotoxicity tests to be practical they must be simple, inexpensive, yet sensitive to a variety of contaminants. A difference between seed germination and root elongation tests is that seed germination tests measure toxicity associated with soils directly, while root elongation tests consider the indirect effects of water-soluble constituents that may be present in site samples.

  16. Germination and elongation of flax in microgravity

    NASA Astrophysics Data System (ADS)

    Levine, H.; Anderson, K.; Boody, A.; Cox, D.; Kuznetsov, O.; Hasenstein, K.

    This experiment was conducted as part of a risk mitigation BIOTUBE Precursor hardware demonstration payload aboard the Space Shuttle Atlantis on STS-101. The objectives were to provide a demonstration and test of the newly developed BIOTUBE water delivery subsystem, and to determine the optimal water volume and germination paper combination for the automated imbibition and germination of flax (Linum usitatissimum) seeds in space. Two different substrate treatments of standard laboratory germination paper were tested for their ability to absorb, distribute, and retain water in microgravity. The first consisted of one layer of thick germination paper (designated "heavy"), and the second consisted of one layer of standard germination paper (designated "normal") under one layer of heavy germination paper. The germination paper strips were cut (4 X 1.6 cm) to fit snugly into seed cassettes. The seeds were attached to them by applying guar glue (1.25% w/v) drops to 8 premarked spots and the seeds orientated with the micropyle ends pointing outward. Water was delivered in 50 μL boluses which slowly traveled down the paper via capillary action (eliminating the complications caused by excess water pooling around the seed's surface). The data indicated that the 480 μL water delivery volume provided the best wetness level treatment for both percent germination (90.6%) and overall root growth (mean = 4.1 mm) during the 34 hour spaceflight experiment. The ground control experiment experienced similar results, but with slightly lower rates of germination (84.4%) and significantly shorter root lengths (2.8 mm). It is not clear if the roots emerged more quickly in microgravity and/or grew faster than the ground controls. The single layer of "Heavy" germination paper generally exhibited better overall growth than the two layered option. This in conjunction with the simplicity of using a single strip per seed cassette argues in favor of its selection. Significant seed position

  17. Germination of Rhizopus oligosporus Sporangiospores

    PubMed Central

    Medwid, Richard D.; Grant, Dale W.

    1984-01-01

    The morphology of Rhizopus oligosporus (NRRL 2710) sporangiospores and their physiological requirements for germination were studied. Germination proceeded in two separable phases: phase I (swelling) and phase II (germ tube protrusion). The optimal conditions for germination were 42°C and pH 4.0. Sporangiospores contained insufficient endogenous carbon for swelling or germination to occur in distilled water. Initial swelling during phase I occurred only in the presence of a suitable carbohydrate. Subsequent production of germ tubes during phase II required exogenous sources of both carbon and nitrogen. Spores germinated most rapidly in mixtures of amino acids; l-proline and l-alanine were the most effective. These amino acids, at concentrations as low as 10−6 M, supported germination when combined with glucose and McIlvaine (citric acid-phosphate) buffer. d-Glucose, d-xylose, and d-mannose were the most effective carbohydrates tested for promotion of germination. Images PMID:16346671

  18. Seed Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Initiation of seed germination is a critical decision for plants. It is important for seed populations under natural conditions to spread the timing of germination of individual seeds to maximize the probability of species survival. Therefore, seeds have evolved the multiple layers of mechanisms tha...

  19. Applying Adaptive Variables in Computerised Adaptive Testing

    ERIC Educational Resources Information Center

    Triantafillou, Evangelos; Georgiadou, Elissavet; Economides, Anastasios A.

    2007-01-01

    Current research in computerised adaptive testing (CAT) focuses on applications, in small and large scale, that address self assessment, training, employment, teacher professional development for schools, industry, military, assessment of non-cognitive skills, etc. Dynamic item generation tools and automated scoring of complex, constructed…

  20. Digital techniques applied to sine test control

    NASA Astrophysics Data System (ADS)

    Westoby, T. J.

    1981-09-01

    Digital techniques are applied to solve problems experienced in analogue circuitry, enabling the design of a highly reliable sine control system. A sine wave is generated whose frequency is proportional to a digital number, held in the counters of the sweep generator, using the frequency related pulse stream. This pulse stream is used to generate a ramp by applying it to a count. The rate of rise is varied by using a rate multiplier arranged to slow the pulse stream as the ramp proceeds. Variation of frequency depends only on the frequency of the pulse stream entering the circuit, and the oscillator runs quite acceptably at 0.1 Hz and 10 kHz. The total distortion at this stage is less than 2%. Since the control signal is quantized, only discrete changes in control are experienced, and the control lines are static most of the time; the digital system can reduce the effects of a noisy return signal by as much as 64 times. The greatest advantage of digital techniques is its use in integrator stabilization. A tracking capacitor ensures that conversion is done to an accuracy of 1%, and residual ripple on the output is removed by a low pass filter.

  1. Projection Registration Applied to Nondestructive Testing

    SciTech Connect

    Bingham, Philip R; Arrowood, Lloyd

    2010-01-01

    Registration of radiographic and computed tomography (CT) data has the potential to allow automated metrology and defect detection. While registration of the three-dimensional reconstructed data is a common task in the medical industry for registration of data sets from multiple detection systems, registration of projection sets has only seen development in the area of tomotherapy. Efforts in projection registration have employed a method named Fourier phase matching (FPM). This work discusses implementation and results for the application of the FPM method to industrial applications for the nondestructive testing (NDT) community. The FPM method has been implemented and modified for industrial application. Testing with simulated and experimental x-ray CT data shows excellent performance with respect to the resolution of the imaging system.

  2. Test fire environmental testing operations at Mound Applied Technologies

    SciTech Connect

    1992-03-01

    This paper describes Mound Laboratory`s environmental testing operations. The function of environmental testing is to perform quality environmental (thermal, mechanical, spin, resistance, visual) testing/conditioning of inert/explosive products to assure their compliance with specified customer acceptance criteria. Capabilities, organization, equipment specifications, and test facilities are summarized.

  3. Assessment of the phytotoxicity of seaport sediments in the framework of a quarry-deposit scenario: germination tests of sediments aged artificially by column leaching.

    PubMed

    Bedell, J-P; Bazin, C; Sarrazin, B; Perrodin, Y

    2013-07-01

    The aim of the Sustainable Management of Sediments Dredged in Seaports (SEDIGEST) project is to assess the risks of treated port sediments for terrestrial ecosystems when deposited in quarries. We simulated the "ageing" of these sediments up to the "moment" when plants can germinate. Sediments were leached by water percolating through a laboratory column. Sediments 1 and 2, taken from the port of Toulon (France), were dried and aired. Sediment 3, taken from the port of Guilvinec (France), was stabilised with lime. Phytotoxicity was evaluated on the three artificially aged sediments using germination and early development tests (48 h to 7 days) by Phytotoxkit F(TM) bioassays. The three dilutions tested were performed with the reference "ISO substrate" and with Lolium perenne sp. (rye grass), Sinapis alba (white mustard), and Lepidium sativum (watercress). The tests performed with sediments 1 and 2 showed (1) a decrease of their toxicity to the germination of the species selected following leaching and (2) that L. perenne was the most sensitive species. The tests performed with sediment 3 showed that it was improper for colonisation even after leaching simulating 16 months of ageing. These germination tests on aged sediments identified the effects of leaching and made it possible to appreciate the capacity of the sediments to allow colonisation by plants. PMID:23456254

  4. Does Cold Plasma Affect Breaking Dormancy and Seed Germination? A Study on Seeds of Lamb's Quarters (Chenopodium album agg.)

    NASA Astrophysics Data System (ADS)

    Božena, Šerá; Michal, Šerý; Vitězslav, Štrañák; Petr, Špatenka; Milan, tichý

    2009-12-01

    Low-pressure discharge is applied for stimulation of germination of two seed lots of Lamb's Quarters (Chenopodium album agg.) with different starting germinations (17%, 8%) and in different stages of dormancy. Different exposition durations with cold plasma treatment were applied. The variable of the ratio cumulative germination was calculated. The Richards' equation was used for curve-fitting and simulation of the growth curves. Population parameters, namely Vi - viability, Me - time, Qu - dispersion, and Sk - skewness, counted from the curves described the germination rate well. Significant differences among Qu confirmed the erratic dormancy and gradual germination of Lamb's Quarters. No difference in the Me parameter was found between two tested seed lots, and no interspecies characteristics were changed using low-pressure discharge. The results suggested that plasma treatment changed seed germination in Lamb's Quarters seeds.

  5. 7 CFR 201.63 - Germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... germination and also to the sum of the germination plus the hard seed when 400 or more seeds are tested. Mean... 7 Agriculture 3 2011-01-01 2011-01-01 false Germination. 201.63 Section 201.63 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  6. 7 CFR 201.63 - Germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... germination and also to the sum of the germination plus the hard seed when 400 or more seeds are tested. Mean... 7 Agriculture 3 2010-01-01 2010-01-01 false Germination. 201.63 Section 201.63 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  7. 7 CFR 201.63 - Germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... germination and also to the sum of the germination plus the hard seed when 400 or more seeds are tested. Mean... 7 Agriculture 3 2014-01-01 2014-01-01 false Germination. 201.63 Section 201.63 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  8. 7 CFR 201.63 - Germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... germination and also to the sum of the germination plus the hard seed when 400 or more seeds are tested. Mean... 7 Agriculture 3 2013-01-01 2013-01-01 false Germination. 201.63 Section 201.63 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  9. 7 CFR 201.63 - Germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... germination and also to the sum of the germination plus the hard seed when 400 or more seeds are tested. Mean... 7 Agriculture 3 2012-01-01 2012-01-01 false Germination. 201.63 Section 201.63 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  10. Toxicity test of the F-Area seep soils by laboratory lettuce seed germination and seedling growth

    SciTech Connect

    Eaton, D.; Murphy, C.E.

    1993-09-01

    This study is a follow-up of a similar study done by Loehle (1990). The objectives of the original study were to: (1) measure the toxicity of groundwater contaminated by the F-Area seepage basins where this water surfaces in a seepline along Fourmile Branch and (2) to evaluate the effectiveness of rainwater for washing contaminants from the soil. Results of seed germination tests show no significant difference between water extracted from one extraction of F-Area seepline soil, soil from a control area, the sixth consecutive extraction from F-Area soil, and a deionized water control. A root-growth assay on the same seeds shows a significant effect with the order of growth, first extraction of F-Area soil

  11. Flight control system design factors for applying automated testing techniques

    NASA Technical Reports Server (NTRS)

    Sitz, Joel R.; Vernon, Todd H.

    1990-01-01

    Automated validation of flight-critical embedded systems is being done at ARC Dryden Flight Research Facility. The automated testing techniques are being used to perform closed-loop validation of man-rated flight control systems. The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 High Alpha Research Vehicle (HARV) automated test systems are discussed. Operationally applying automated testing techniques has accentuated flight control system features that either help or hinder the application of these techniques. The paper also discusses flight control system features which foster the use of automated testing techniques.

  12. Mathematical models applied in inductive non-destructive testing

    NASA Astrophysics Data System (ADS)

    Wac-Wlodarczyk, A.; Goleman, R.; Czerwinski, D.; Gizewski, T.

    Non-destructive testing are the wide group of investigative methods of non-homogenous material. Methods of computer tomography, ultrasonic, magnetic and inductive methods still developed are widely applied in industry. In apparatus used for non-destructive tests, the analysis of signals is made on the basis of complex system answers. The answer is linearized due to the model of research system. In this paper, the authors will discuss the applications of the mathematical models applied in investigations of inductive magnetic materials. The statistical models and other gathered in similarity classes will be taken into consideration. Investigation of mathematical models allows to choose the correct method, which in consequence leads to precise representation of the inner structure of examined object. Inductive research of conductive media, especially those with ferromagnetic properties, are run with high frequency magnetic field (eddy-currents method), which considerably decrease penetration depth.

  13. Applying Independent Verification and Validation to Automatic Test Equipment

    NASA Technical Reports Server (NTRS)

    Calhoun, Cynthia C.

    1997-01-01

    This paper describes a general overview of applying Independent Verification and Validation (IV&V) to Automatic Test Equipment (ATE). The overview is not inclusive of all IV&V activities that can occur or of all development and maintenance items that can be validated and verified, during the IV&V process. A sampling of possible IV&V activities that can occur within each phase of the ATE life cycle are described.

  14. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... to size or appearance. (b) When only a germination test is required and the pure seed is estimated or determined to be at least 98 percent, the pure seed for the germination test may be taken indiscriminately... 7 Agriculture 3 2014-01-01 2014-01-01 false Source of seeds for germination. 201.53 Section...

  15. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... to size or appearance. (b) When only a germination test is required and the pure seed is estimated or determined to be at least 98 percent, the pure seed for the germination test may be taken indiscriminately... 7 Agriculture 3 2010-01-01 2010-01-01 false Source of seeds for germination. 201.53 Section...

  16. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... to size or appearance. (b) When only a germination test is required and the pure seed is estimated or determined to be at least 98 percent, the pure seed for the germination test may be taken indiscriminately... 7 Agriculture 3 2012-01-01 2012-01-01 false Source of seeds for germination. 201.53 Section...

  17. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... to size or appearance. (b) When only a germination test is required and the pure seed is estimated or determined to be at least 98 percent, the pure seed for the germination test may be taken indiscriminately... 7 Agriculture 3 2013-01-01 2013-01-01 false Source of seeds for germination. 201.53 Section...

  18. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... to size or appearance. (b) When only a germination test is required and the pure seed is estimated or determined to be at least 98 percent, the pure seed for the germination test may be taken indiscriminately... 7 Agriculture 3 2011-01-01 2011-01-01 false Source of seeds for germination. 201.53 Section...

  19. Applied methods of testing and evaluation for IR imaging system

    NASA Astrophysics Data System (ADS)

    Liao, Xiao-yue; Lu, Jin

    2009-07-01

    Different methods of testing and evaluation for IR imaging system are used with the application of the 2nd and the 3rd generation infrared detectors. The performance of IR imaging system can be reflected by many specifications, such as Noise Equivalent Temperature Difference (NETD), Nonuniformity, system Modulation Transfer Function (MTF), Minimum Resolvable Temperature Difference (MRTD), and Minimum Detectable Temperature Difference (MRTD) etc. The sensitivity of IR sensors is estimated by NETD. The sensitivity of thermal imaging sensors and space resolution are evaluated by MRTD, which is the chief specification of system. In this paper, the theoretical analysis of different testing methods is introduced. The characteristics of them are analyzed and compared. Based on discussing the factors that affect measurement results, an applied method of testing NETD and MRTD for IR system is proposed.

  20. Effect of chemical and physical factors to improve the germination rate of Echinacea angustifolia seeds.

    PubMed

    Chuanren, Duan; Bochu, Wang; Wanqian, Liu; Jing, Chen; Jie, Lian; Huan, Zhao

    2004-09-01

    Seeds of Echinacea angustifolia are known for their deep dormancy. In this paper, we studied the responses of E. angustifolia seeds to some chemical and physical factors, such as scarification, chilling (5 degrees C) period, light and applied BA (6-benzylaminopurine), GA3 (gibberellic acid) and sound stimulation. When the seed coat layers were removed, the germination rate grew up from 6 to 20% (incubated in light) and the mean time germination (MTG) was reduced from 18 to 6.6 days. On the basis of layers-removed, chilling and continuous light gave significantly higher germination rate (up to 70%). Compare the data of seeds chilled by 0, 6, 12, 18 and 24 days, the maximum germination rate (up to 70%) achieved at 18-days chilling treatment. Further increases in the chilling period could slightly improve germination. Exogenous application of 0.1, 0.2, 0.3 mg/L GA3 or BA in the previous pretreatment increased germination to 78, 90 and 84% or 76, 86 and 84%, respectively. Obviously, the best concentration of GA or BA is 0.3 mg/L. And the GA3 or BA treatment shortened the MTG to about 4 days. The influence of sound stimulation was also tested in the experiment. The result showed that one 100 dB and 1000 Hz sound wave (sine-wave) was beneficial to the germination of E. angustifolia seeds. PMID:15342019

  1. 7 CFR 201.6 - Germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... include the records of all laboratory tests for germination and hard seed for each lot of seed offered for... 7 Agriculture 3 2014-01-01 2014-01-01 false Germination. 201.6 Section 201.6 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  2. 7 CFR 201.6 - Germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... include the records of all laboratory tests for germination and hard seed for each lot of seed offered for... 7 Agriculture 3 2012-01-01 2012-01-01 false Germination. 201.6 Section 201.6 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  3. 7 CFR 201.6 - Germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... include the records of all laboratory tests for germination and hard seed for each lot of seed offered for... 7 Agriculture 3 2013-01-01 2013-01-01 false Germination. 201.6 Section 201.6 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  4. 7 CFR 201.6 - Germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... include the records of all laboratory tests for germination and hard seed for each lot of seed offered for... 7 Agriculture 3 2011-01-01 2011-01-01 false Germination. 201.6 Section 201.6 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  5. 7 CFR 201.6 - Germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... include the records of all laboratory tests for germination and hard seed for each lot of seed offered for... 7 Agriculture 3 2010-01-01 2010-01-01 false Germination. 201.6 Section 201.6 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  6. Testing composite parametrical hypotheses without applying the reduction

    NASA Astrophysics Data System (ADS)

    Vlasov, V.; Vlasova, S.; Tolokonsky, A.

    2016-01-01

    Usually when the parametrical hypotheses are being tested the Wald reduction from composite hypothesis to the simple one is used. However, in order to apply the reduction method it is needed to know the distribution law of unknown parameter. Practically such a law cannot be determined precisely using the experimental data. First of all, it requires long supervision over the controlled stationary process to provide an inalterability of probability characteristics of the process. In practice the modifications in technological process could be made, and therefore the probability characteristics of the process can also change. Using the example of exponential distribution the algorithm of testing composite parametrical hypothesis about the distribution parameter which does not exceed the declared threshold value without use of reduction is considered in article. Such approach is based on the fact that the partition boundary of the sample space depends monotonously on unknown value of the interest parameter.

  7. A Germination Simulation.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1995-01-01

    Presents an activity that involves using sponge seedlings to demonstrate the germination process without the usual waiting period. Discusses epigeous versus hypogeous germination, and cotyledon number and biodiversity. (JRH)

  8. Applying well flow adapted filtering to transient pumping tests

    NASA Astrophysics Data System (ADS)

    Zech, Alraune; Attinger, Sabine

    2014-05-01

    Transient pumping tests are often used to estimate porous medium characteristics like hydraulic conductivity and storativity. The interpretation of pumping test drawdowns is based on methods which are normally developed under the assumption of homogeneous porous media. However aquifer heterogeneity strongly impacts on well flow pattern, in particular in the vicinity of the pumping well. The purpose of this work is to present a method to interpret drawdowns of transient pumping tests in heterogeneous porous media. With this method we are able to describe the effects that statistical quantities like variance and correlation length have on pumping test drawdowns. Furthermore it allows inferring on the statistical parameters of aquifer heterogeneity from drawdown data by invers estimation, which is not possible using methods for homogeneous media like Theis' solution. The method is based on a representative description of hydraulic conductivity for radial flow regimes. It is derived from a well flow adapted filtering procedure (Coarse Graining), where the heterogeneity of hydraulic conductivity is assumed to be log-normal distributed with a Gaussian correlation structure. applying the up scaled hydraulic conductivity to the groundwater flow equation results in a hydraulic head which depends on the statistical parameters of the porous medium. It describes the drawdown of a transient pumping test in heterogeneous media. We used an ensemble of transient pumping test simulations to verify the up scaled drawdown solution. We generated transient pumping tests in heterogeneous media for various values of the statistical parameters variance and correlation length and evaluated their impact on the drawdown behavior as well as on the temporal evolution. We further examined the impact of several aspects like the location of an observation well or the local conductivity at the pumping well on the drawdown behavior. This work can be understood as an expansion of the work of Zech et

  9. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Number of seeds for germination. 201.54 Section 201.54..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.54 Number of seeds for germination....

  10. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Number of seeds for germination. 201.54 Section 201.54..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.54 Number of seeds for germination....

  11. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Number of seeds for germination. 201.54 Section 201.54..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.54 Number of seeds for germination....

  12. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Number of seeds for germination. 201.54 Section 201.54..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.54 Number of seeds for germination....

  13. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Number of seeds for germination. 201.54 Section 201.54..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of the Act § 201.54 Number of seeds for germination....

  14. Effect of fungicide on Wyoming big sagebrush seed germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because fungal infection may complicate both the logistics and the interpretation of germination tests, seeds are sometimes treated with chemical fungicides. Fungicides may reduce the germination rate and/or germination percentage, and should be avoided unless fungal contamination is severe enough ...

  15. A general diagnostic model applied to language testing data.

    PubMed

    von Davier, Matthias

    2008-11-01

    Probabilistic models with one or more latent variables are designed to report on a corresponding number of skills or cognitive attributes. Multidimensional skill profiles offer additional information beyond what a single test score can provide, if the reported skills can be identified and distinguished reliably. Many recent approaches to skill profile models are limited to dichotomous data and have made use of computationally intensive estimation methods such as Markov chain Monte Carlo, since standard maximum likelihood (ML) estimation techniques were deemed infeasible. This paper presents a general diagnostic model (GDM) that can be estimated with standard ML techniques and applies to polytomous response variables as well as to skills with two or more proficiency levels. The paper uses one member of a larger class of diagnostic models, a compensatory diagnostic model for dichotomous and partial credit data. Many well-known models, such as univariate and multivariate versions of the Rasch model and the two-parameter logistic item response theory model, the generalized partial credit model, as well as a variety of skill profile models, are special cases of this GDM. In addition to an introduction to this model, the paper presents a parameter recovery study using simulated data and an application to real data from the field test for TOEFL Internet-based testing. PMID:17535481

  16. Effect of new organic supplement (Panchgavya) on seed germination and soil quality.

    PubMed

    Jain, Paras; Sharma, Ravi Chandra; Bhattacharyya, Pradip; Banik, Pabitra

    2014-04-01

    We studied the suitability of Panchgavya (five products of cow), new organic amendment, application on seed germination, plant growth, and soil health. After characterization, Panchgavya was mixed with water to form different concentration and was tested for seed germination, germination index, and root and shoot growth of different seedlings. Four percent solution of Panchgavya was applied to different plants to test its efficacy. Panchgavya and other two organic amendments were incorporated in soil to test the change of soil chemical and microbiological parameters. Panchgavya contained higher nutrients as compared to farm yard manure (FYM) and vermicompost. Its application on different seeds has positively influenced germination percentage, germination index, root and shoot length, and fresh and dry weight of the seedling. Water-soluble macronutrients including pH and metal were positively and negatively correlated with the growth parameters, respectively. Four percent solution of Panchgavya application on some plants showed superiority in terms of plant height and chlorophyll content. Panchgavya-applied soil had higher values of macro and micronutrients (zinc, copper, and manganese), microbial activity as compared to FYM, and vermicompost applied soils. Application of Panchgavya can be gainfully used as an alternative organic supplement in agriculture. PMID:24234225

  17. Effects of disturbance on germination and seedling establishment in a coastal prairie grassland: A test of the competitive release hypothesis

    USGS Publications Warehouse

    Jutila, H.M.; Grace, J.B.

    2002-01-01

    1. We evaluated the responses of native grassland sods to a variety of types of disturbance in order to assess hypotheses about the competitive effects of established vegetation on seed germination and seedling establishment. In particular, we consider whether germination is more responsive to the magnitude and duration of vegetation removal (competitive release) or to individual disturbance types (specific effects). 2. Field-collected sods of coastal tallgrass prairie were subjected to no manipulation, cutting with clippings left, cutting with clippings removed (hayed), burning, and complete destruction of established vegetation under greenhouse conditions. The emergence and fate of seedlings, as well as light penetration through the canopy, were followed for a period of 4.5 months. 3. Total seedling emergence increased from cut to control, hayed, burned and plants-removed treatments. Several periods of increased seedling emergence suggested responses to both light penetration and seasonal change. 4. Species richness was lowest in cut sods and highest in sods that had plants removed or were burned. Rarefaction analysis showed that these differences were largely those expected from differences in seedling number, except for the cut treatment, which produced fewer species per seedling than other treatments. 5. Indicator species analysis and ordination methods revealed that seedling community composition overlapped strongly across all treatments, although the area of ordination space did increase with increasing numbers of seedlings. 6. Overall, most of the effects of disturbance could be explained by cumulative light penetration to the soil surface, an indicator of total competitive release, although a few specific effects could be found (particularly for the cutting treatment). Thus, these results generally support the competitive release hypothesis.

  18. Reliability Testing Procedure for MEMS IMUs Applied to Vibrating Environments

    PubMed Central

    De Pasquale, Giorgio; Somà, Aurelio

    2010-01-01

    The diffusion of micro electro-mechanical systems (MEMS) technology applied to navigation systems is rapidly increasing, but currently, there is a lack of knowledge about the reliability of this typology of devices, representing a serious limitation to their use in aerospace vehicles and other fields with medium and high requirements. In this paper, a reliability testing procedure for inertial sensors and inertial measurement units (IMU) based on MEMS for applications in vibrating environments is presented. The sensing performances were evaluated in terms of signal accuracy, systematic errors, and accidental errors; the actual working conditions were simulated by means of an accelerated dynamic excitation. A commercial MEMS-based IMU was analyzed to validate the proposed procedure. The main weaknesses of the system have been localized by providing important information about the relationship between the reliability levels of the system and individual components. PMID:22315550

  19. Oxygen requirement of germinating flax seeds

    NASA Astrophysics Data System (ADS)

    Kuznetsov, Oleg A.; Hasenstein, K. H.

    2003-05-01

    Plant experiments in earth orbit are typically prepared on the ground and germinated in orbit to study gravity effects on the developing seedlings. Germination requires the breakdown of storage compounds, and this metabolism depends upon respiration, making oxygen one of the limiting factors in seed germination. In microgravity lack of run-off of excess water requires careful testing of water dispensation and oxygen availability. In preparation for a shuttle experiment (MICRO on STS-107) we studied germination and growth of flax ( Linum usitatissimum L.) seedlings in the developed hardware (Magnetic Field Chamber, MFC). We tested between four to 32 seeds per chamber (air volume = 14 mL) and after 36 h measured the root length. At 90 μl O 2 per seed (32 seeds/chamber), the germination decreased from 94 to 69%, and the root length was reduced by 20%, compared to 8 seeds per chamber. Based on the percent germination and root length obtained in controlled gas mixtures between 3.6 and 21.6% O 2 we determined the lower limit of reliable germination to be 10 vol. % O 2 at atmospheric pressure. Although the oxygen available in the MFC's can support the intended number of seeds, the data show that seed storage and microgravity-related limitations may reduce germination.

  20. Oxygen requirement of germinating flax seeds

    NASA Technical Reports Server (NTRS)

    Kuznetsov, Oleg A.; Hasenstein, K. H.; Hasentein, K. H. (Principal Investigator)

    2003-01-01

    Plant experiments in earth orbit are typically prepared on the ground and germinated in orbit to study gravity effects on the developing seedlings. Germination requires the breakdown of storage compounds, and this metabolism depends upon respiration, making oxygen one of the limiting factors in seed germination. In microgravity lack of run-off of excess water requires careful testing of water dispensation and oxygen availability. In preparation for a shuttle experiment (MICRO on STS-107) we studied germination and growth of flax (Linum usitatissimum L.) seedlings in the developed hardware (Magnetic Field Chamber, MFC). We tested between four to 32 seeds per chamber (air volume=14 mL) and after 36 h measured the root length. At 90 microliters O2 per seed (32 seeds/chamber), the germination decreased from 94 to 69%, and the root length was reduced by 20%, compared to 8 seeds per chamber. Based on the percent germination and root length obtained in controlled gas mixtures between 3.6 and 21.6% O2 we determined the lower limit of reliable germination to be 10 vol. % O2 at atmospheric pressure. Although the oxygen available in the MFC's can support the intended number of seeds, the data show that seed storage and microgravity-related limitations may reduce germination. c2003 Published by Elsevier Ltd on behalf of COSPAR.

  1. Multi-matrix, dual polarity, tandem mass spectrometry imaging strategy applied to a germinated maize seed: toward mass spectrometry imaging of an untargeted metabolome

    SciTech Connect

    Feenstra, Adam D.; Hansen, Rebecca L.; Lee, Young Jin

    2015-08-27

    Mass spectrometry imaging (MSI) provides high spatial resolution information that is unprecedented in traditional metabolomics analyses; however, the molecular coverage is often limited to a handful of compounds and is insufficient to understand overall metabolomic changes of a biological system. Here, we propose an MSI methodology to increase the diversity of chemical compounds that can be imaged and identified, in order to eventually perform untargeted metabolomic analysis using MSI. We use the desorption/ionization bias of various matrixes for different metabolite classes along with dual polarities and a tandem MSI strategy. The use of multiple matrixes and dual polarities allows us to visualize various classes of compounds, while data-dependent MS/MS spectra acquired in the same MSI scans allow us to identify the compounds directly on the tissue. In a proof of concept application to a germinated corn seed, a total of 166 unique ions were determined to have high-quality MS/MS spectra, without counting structural isomers, of which 52 were identified as unique compounds. According to an estimation based on precursor MSI datasets, we expect over five hundred metabolites could be potentially identified and visualized once all experimental conditions are optimized and an MS/MS library is available. Finally, metabolites involved in the glycolysis pathway and tricarboxylic acid cycle were imaged to demonstrate the potential of this technology to better understand metabolic biology.

  2. Multi-matrix, dual polarity, tandem mass spectrometry imaging strategy applied to a germinated maize seed: toward mass spectrometry imaging of an untargeted metabolome.

    PubMed

    Feenstra, Adam D; Hansen, Rebecca L; Lee, Young Jin

    2015-11-01

    Mass spectrometry imaging (MSI) provides high spatial resolution information that is unprecedented in traditional metabolomics analyses; however, the molecular coverage is often limited to a handful of compounds and is insufficient to understand overall metabolomic changes of a biological system. Here, we propose an MSI methodology to increase the diversity of chemical compounds that can be imaged and identified, in order to eventually perform untargeted metabolomic analysis using MSI. In this approach, we use the desorption/ionization bias of various matrixes for different metabolite classes along with dual polarities and a tandem MSI strategy. The use of multiple matrixes and dual polarities allows us to visualize various classes of compounds, while data-dependent MS/MS spectra acquired in the same MSI scans allow us to identify the compounds directly on the tissue. In a proof of concept application to a germinated corn seed, a total of 166 unique ions were determined to have high-quality MS/MS spectra, without counting structural isomers, of which 52 were identified as unique compounds. According to an estimation based on precursor MSI datasets, we expect over five hundred metabolites could be potentially identified and visualized once all experimental conditions are optimized and an MS/MS library is available. Lastly, metabolites involved in the glycolysis pathway and tricarboxylic acid cycle were imaged to demonstrate the potential of this technology to better understand metabolic biology. PMID:26339687

  3. Multi-matrix, dual polarity, tandem mass spectrometry imaging strategy applied to a germinated maize seed: toward mass spectrometry imaging of an untargeted metabolome

    DOE PAGESBeta

    Feenstra, Adam D.; Hansen, Rebecca L.; Lee, Young Jin

    2015-08-27

    Mass spectrometry imaging (MSI) provides high spatial resolution information that is unprecedented in traditional metabolomics analyses; however, the molecular coverage is often limited to a handful of compounds and is insufficient to understand overall metabolomic changes of a biological system. Here, we propose an MSI methodology to increase the diversity of chemical compounds that can be imaged and identified, in order to eventually perform untargeted metabolomic analysis using MSI. We use the desorption/ionization bias of various matrixes for different metabolite classes along with dual polarities and a tandem MSI strategy. The use of multiple matrixes and dual polarities allows usmore » to visualize various classes of compounds, while data-dependent MS/MS spectra acquired in the same MSI scans allow us to identify the compounds directly on the tissue. In a proof of concept application to a germinated corn seed, a total of 166 unique ions were determined to have high-quality MS/MS spectra, without counting structural isomers, of which 52 were identified as unique compounds. According to an estimation based on precursor MSI datasets, we expect over five hundred metabolites could be potentially identified and visualized once all experimental conditions are optimized and an MS/MS library is available. Finally, metabolites involved in the glycolysis pathway and tricarboxylic acid cycle were imaged to demonstrate the potential of this technology to better understand metabolic biology.« less

  4. Asymbiotic Germination Response to Photoperiod and Nutritional Media in Six Populations of Calopogon tuberosus var. tuberosus (Orchidaceae): Evidence for Ecotypic Differentiation

    PubMed Central

    Kauth, Philip J.; Kane, Michael E.; Vendrame, Wagner A.; Reinhardt-Adams, Carrie

    2008-01-01

    Background and Aims Ecotypic differentiation has been explored in numerous plant species, but has been largely ignored in the Orchidaceae. Applying a specific germination protocol for widespread seed sources may be unreliable due to inherent physiological or genetic differences in localized populations. It is crucial to determine whether ecotypic differentiation exists for restoration and conservation programmes. Calopogon tuberosus var. tuberosus, a widespread terrestrial orchid of eastern North America, is a model species to explore ecotypic differences in germination requirements, as this species occupies diverse habitats spanning a wide geographical range. Methods Mature seeds were collected from south Florida, north central Florida, three locations in South Carolina, and the upper Michigan peninsula. Effects of three photoperiods (8/16, 12/12, 16/8 h L/D) were examined on asymbiotic in vitro seed germination and seedling development of C. tuberosus. Germination and early development was monitored for 8 weeks, while advanced development was monitored for an additional 8 weeks. In an additional experiment, asymbiotic seed germination and development was monitored for 8 weeks on six culture media (BM-1 terrestrial orchid medium, Knudson C, Malmgrem, half-strength MS, P723, and Vacin and Went). A tetrazolium test for embryo viability was performed. Key Results Short days promoted the highest germination among Florida populations, but few differences among photoperiods in other seed sources existed. Different media had little effect on the germination of Michigan and Florida populations, but germination of South Carolina seeds was higher on media with higher calcium and magnesium. Tetrazolium testing confirmed that South Carolina seeds exhibited low viability while viability was higher in Florida seeds. Seed germination and corm formation was rapid in Michigan seeds across all treatments. Michigan seedlings allocated more biomass to corms compared with other seed

  5. Applying the Implicit Association Test to Measure Intolerance of Uncertainty.

    PubMed

    Mosca, Oriana; Dentale, Francesco; Lauriola, Marco; Leone, Luigi

    2016-08-01

    Intolerance of Uncertainty (IU) is a key trans-diagnostic personality construct strongly associated with anxiety symptoms. Traditionally, IU is measured through self-report measures that are prone to bias effects due to impression management concerns and introspective difficulties. Moreover, self-report scales are not able to intercept the automatic associations that are assumed to be main determinants of several spontaneous responses (e.g., emotional reactions). In order to overcome these limitations, the Implicit Association Test (IAT) was applied to measure IU, with a particular focus on reliability and criterion validity issues. The IU-IAT and the Intolerance of Uncertainty Inventory (IUI) were administered to an undergraduate student sample (54 females and 10 males) with a mean age of 23 years (SD = 1.7). Successively, participants were asked to provide an individually chosen uncertain event from their own lives that may occur in the future and were requested to identify a number of potential negative consequences of it. Participants' responses in terms of cognitive thoughts (i.e., cognitive appraisal) and worry reactions toward these events were assessed using the two subscales of the Worry and Intolerance of Uncertainty Beliefs Questionnaire. The IU-IAT showed an adequate level of internal consistency and a not significant correlation with the IUI. A path analysis model, accounting for 35% of event-related worry, revealed that IUI had a significant indirect effect on the dependent variable through event-related IU thoughts. By contrast, as expected, IU-IAT predicted event-related worry independently from IU thoughts. In accordance with dual models of social cognition, these findings suggest that IU can influence event-related worry through two different processing pathways (automatic vs. deliberative), supporting the criterion and construct validity of the IU-IAT. The potential role of the IU-IAT for clinical applications was discussed. PMID:27451266

  6. Similitude requirements and scaling relationships as applied to model testing

    NASA Technical Reports Server (NTRS)

    Wolowicz, C. H.; Brown, J. S., Jr.; Gilbert, W. P.

    1979-01-01

    The similitude requirements for the most general test conditions are presented. These similitude requirements are considered in relation to the scaling relationships, test technique, test conditions (including supersonic flow), and test objectives. Particular emphasis is placed on satisfying the various similitude requirements for incompressible and compressible flow conditions. For free flying models tests, the test velocities for incompressible flow are scaled from Froude number similitude requirements and those for compressible flow are scaled from Mach number similitude requirements. The limitations of various test techniques are indicated, with emphasis on the free flying model.

  7. Germination and elongation of flax in microgravity

    NASA Astrophysics Data System (ADS)

    Levine, Howard G.; Anderson, Ken; Boody, April; Cox, Dave; Kuznetsov, Oleg A.; Hasenstein, Karl H.

    2003-05-01

    This experiment was conducted as part of a risk mitigation payload aboard the Space Shuttle Atlantis on STS-101. The objectives were to test a newly developed water delivery system, and to determine the optimal combination of water volume and substrate for the imbibition and germination of flax ( Linum usitatissimum) seeds in space. Two different combinations of germination paper were tested for their ability to absorb, distribute, and retain water in microgravity. A single layer of thick germination paper was compared with one layer of thin germination paper under a layer of thick paper. Paper strips were cut to fit snugly into seed cassettes, and seeds were glued to them with the micropyle ends pointing outward. Water was delivered in small increments that traveled through the paper via capillary action. Three water delivery volumes were tested, with the largest (480 μL) outperforming the 400 μL, and 320 μL volumes for percent germination (90.6%) and root growth (mean = 4.1 mm) during the 34-hour spaceflight experiment. The ground control experiment yielded similar results, but with lower rates of germination (84.4%) and shorter root lengths (mean = 2.8 mm). It is not clear if the roots emerged more quickly in microgravity and/or grew faster than the ground controls. The single layer of thick germination paper generally exhibited better overall growth than the two layered option. Significant seed position effects were observed in both the flight and ground control experiments. Overall, the design of the water delivery system, seed cassettes and the germination paper strip concept was validated as an effective method for promoting seed germination and root growth under microgravity conditions.

  8. Germination and elongation of flax in microgravity

    NASA Technical Reports Server (NTRS)

    Levine, Howard G.; Anderson, Ken; Boody, April; Cox, Dave; Kuznetsov, Oleg A.; Hasenstein, Karl H.

    2003-01-01

    This experiment was conducted as part of a risk mitigation payload aboard the Space Shuttle Atlantis on STS-101. The objectives were to test a newly developed water delivery system, and to determine the optimal combination of water volume and substrate for the imbibition and germination of flax (Linum usitatissimum) seeds in space. Two different combinations of germination paper were tested for their ability to absorb, distribute, and retain water in microgravity. A single layer of thick germination paper was compared with one layer of thin germination paper under a layer of thick paper. Paper strips were cut to fit snugly into seed cassettes, and seeds were glued to them with the micropyle ends pointing outward. Water was delivered in small increments that traveled through the paper via capillary action. Three water delivery volumes were tested, with the largest (480 microliters) outperforming the 400 microliters and 320 microliters volumes for percent germination (90.6%) and root growth (mean=4.1 mm) during the 34-hour spaceflight experiment. The ground control experiment yielded similar results, but with lower rates of germination (84.4%) and shorter root lengths (mean=2.8 mm). It is not clear if the roots emerged more quickly in microgravity and/or grew faster than the ground controls. The single layer of thick germination paper generally exhibited better overall growth than the two layered option. Significant seed position effects were observed in both the flight and ground control experiments. Overall, the design of the water delivery system, seed cassettes and the germination paper strip concept was validated as an effective method for promoting seed germination and root growth under microgravity conditions. c2003 COSPAR. Published by Elsevier Ltd. All rights reserved.

  9. Germination and inactivation of Bacillus subtilis spores induced by moderate hydrostatic pressure.

    PubMed

    Nguyen Thi Minh, Hue; Dantigny, Philippe; Perrier-Cornet, Jean-Marie; Gervais, Patrick

    2010-12-01

    In this study, we investigated the mechanisms of spore inactivation by high pressure at moderate temperatures to optimize the sterilization efficiency of high-pressure treatments. Bacillus subtilis spores were first subjected to different pressure treatments ranging from 90 to 550 MPa at 40°C, with holding times from 10 min to 4 h. These treatments alone caused slight inactivation, which was related to the pressure-induced germination of the spores. After these pressures treatments, the sensitivity of these processed spores to heat (80°C/10 min) or to high pressure (350 MPa/40°C/10 min) was tested to determine the pressure-induced germination rate and the advancement of the spores in the germination process. The subsequent heat or pressure treatments were applied immediately after decompression from the first pressure treatment or after a holding time at atmospheric pressure. As already known, the spore germination is more efficient at low pressure level than at high pressure level. Our results show that this low germination efficiency at high pressure seemed not to be related either to a lower induction or a difference in the induction mechanisms but rather to an inhibition of enzyme activities which are involved in germination process. In fact, high pressure was necessary and very efficient in inducing spore germination. However, it seemed to slow the enzymatic digestion of the cortex, which is required for germinated spores to be inactivated by pressure. Although these results indicate that high-pressure treatments are more efficient when the two treatments are combined, a small spore population still remained dormant and was not inactivated with any holding time or pressure level. PMID:20589839

  10. Germination and seedling development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cottonseed germination and seedling development are highly sensitive to the environment at planting and for several weeks after that. Major factors that affect germination and development are temperature, water availability, soil conditions such as compaction, rhizosphere gases, and seed and seedlin...

  11. The oxygen requirement of germinating flax seeds

    NASA Astrophysics Data System (ADS)

    Kuznetsov, O.; Hasenstein, K.

    Experiments for earth orbit are typically prepared on the ground and often germinated in orbit in order to study gravity effects on developing seedlings. Germination requires the breakdown of storage compounds and respiration. In orbit the formation of a water layer around the seed may further limit oxygen availability. Therefore, the oxygen content of the available gas volume is one of the limiting factors for seed germination. In preparation for an upcoming shuttle experiment (MICRO on STS-107) we studied germination and growth of flax (Linum usitatissimum L.) seedlings in the developed hardware. We tested per seed chamber (gas volume = 14 mL, O2 = 2.9 mL) between 4 to 32 seeds glued to germination paper by 1% (w/v) gum guar. A lexan cover and a gasket hermetically sealed each of the eight chambers. For imbibition of the seeds a previously optimized amount of distilled water was dispensed through sealed inlets. The seedlings were allowed to grow for either 32 to 48 h on a clinostat or without microgravity simulation. Then their root length was measured. With 32 seeds per chamber, four times the intended number of seeds for the flight, the germination rate decreased from 94 to 69%, and the root length was reduced by 20%. Experiments on the germination and root length in controlled atmospheres (5, 10, 15 and 21% O2 ) suggest that germination and growth for two days requires about 200 :l of O (1 mL air) per seed. Our2 experiments correlate oxygen dependency from seed mass and germination temperature, and analyze accumulation of gaseous metabolites (supported by NASA grant NAG10-0190).

  12. Priming effects on seed germination in Tecoma stans (Bignoniaceae) and Cordia megalantha (Boraginaceae), two tropical deciduous tree species

    NASA Astrophysics Data System (ADS)

    Alvarado-López, Sandra; Soriano, Diana; Velázquez, Noé; Orozco-Segovia, Alma; Gamboa-deBuen, Alicia

    2014-11-01

    Successful revegetation necessarily requires the establishment of a vegetation cover and one of the challenges for this is the scarce knowledge about germination and seedling establishment of wild tree species. Priming treatments (seed hydration during a specific time followed by seed dehydration) could be an alternative germination pre-treatment to improve plant establishment. Natural priming (via seed burial) promotes rapid and synchronous germination as well as the mobilisation of storage reserves; consequently, it increases seedling vigour. These metabolic and physiological responses are similar to those occurring as a result of the laboratory seed priming treatments (osmopriming and matrix priming) applied successfully to agricultural species. In order to know if natural priming had a positive effect on germination of tropical species we tested the effects of natural priming on imbibition kinetics, germination parameters (mean germination time, lag time and germination rate and percentage) and reserve mobilisation in the seeds of two tree species from a tropical deciduous forest in south-eastern México: Tecoma stans (L Juss. Ex Kunth) and Cordia megalantha (S.F Blake). The wood of both trees are useful for furniture and T. stans is a pioneer tree that promotes soil retention in disturbed areas. We also compared the effect of natural priming with that of laboratory matrix priming (both in soil). Matrix priming improved germination of both studied species. Natural priming promoted the mobilisation of proteins and increased the amount of free amino acids and of lipid degradation in T. stans but not in C. megalantha. Our results suggest that the application of priming via the burial of seeds is an easy and inexpensive technique that can improve seed germination and seedling establishment of tropical trees with potential use in reforestation and restoration practices.

  13. Functional characterisation of germinant receptors in Clostridium botulinum and Clostridium sporogenes presents novel insights into spore germination systems.

    PubMed

    Brunt, Jason; Plowman, June; Gaskin, Duncan J H; Itchner, Manoa; Carter, Andrew T; Peck, Michael W

    2014-09-01

    Clostridium botulinum is a dangerous pathogen that forms the highly potent botulinum toxin, which when ingested causes a deadly neuroparalytic disease. The closely related Clostridium sporogenes is occasionally pathogenic, frequently associated with food spoilage and regarded as the non-toxigenic equivalent of Group I C. botulinum. Both species form highly resistant spores that are ubiquitous in the environment and which, under favourable growth conditions germinate to produce vegetative cells. To improve the control of botulinum neurotoxin-forming clostridia, it is imperative to comprehend the mechanisms by which spores germinate. Germination is initiated following the recognition of small molecules (germinants) by a specific germinant receptor (GR) located in the spore inner membrane. The present study precisely defines clostridial GRs, germinants and co-germinants. Group I C. botulinum ATCC3502 contains two tricistronic and one pentacistronic GR operons, while C. sporogenes ATCC15579 has three tricistronic and one tetracistronic GR operons. Insertional knockout mutants, allied with characterisation of recombinant GRs shows for the first time that amino acid stimulated germination in C. botulinum requires two tri-cistronic encoded GRs which act in synergy and cannot function individually. Spore germination in C. sporogenes requires one tri-cistronic GR. Two other GRs form part of a complex involved in controlling the rate of amino-acid stimulated germination. The suitability of using C. sporogenes as a substitute for C. botulinum in germination studies and food challenge tests is discussed. PMID:25210747

  14. Flight control system design factors for applying automated testing techniques

    NASA Technical Reports Server (NTRS)

    Sitz, Joel R.; Vernon, Todd H.

    1990-01-01

    The principal design features and operational experiences of the X-29 forward-swept-wing aircraft and F-18 high alpha research vehicle (HARV) automated test systems are discussed. It is noted that operational experiences in developing and using these automated testing techniques have highlighted the need for incorporating target system features to improve testability. Improved target system testability can be accomplished with the addition of nonreal-time and real-time features. Online access to target system implementation details, unobtrusive real-time access to internal user-selectable variables, and proper software instrumentation are all desirable features of the target system. Also, test system and target system design issues must be addressed during the early stages of the target system development. Processing speeds of up to 20 million instructions/s and the development of high-bandwidth reflective memory systems have improved the ability to integrate the target system and test system for the application of automated testing techniques. It is concluded that new methods of designing testability into the target systems are required.

  15. Aerodynamic Reconstruction Applied to Parachute Test Vehicle Flight Data Analysis

    NASA Technical Reports Server (NTRS)

    Cassady, Leonard D.; Ray, Eric S.; Truong, Tuan H.

    2013-01-01

    The aerodynamics, both static and dynamic, of a test vehicle are critical to determining the performance of the parachute cluster in a drop test and for conducting a successful test. The Capsule Parachute Assembly System (CPAS) project is conducting tests of NASA's Orion Multi-Purpose Crew Vehicle (MPCV) parachutes at the Army Yuma Proving Ground utilizing the Parachute Test Vehicle (PTV). The PTV shape is based on the MPCV, but the height has been reduced in order to fit within the C-17 aircraft for extraction. Therefore, the aerodynamics of the PTV are similar, but not the same as, the MPCV. A small series of wind tunnel tests and computational fluid dynamics cases were run to modify the MPCV aerodynamic database for the PTV, but aerodynamic reconstruction of the flights has proven an effective source for further improvements to the database. The acceleration and rotational rates measured during free flight, before parachute inflation but during deployment, were used to con rm vehicle static aerodynamics. A multibody simulation is utilized to reconstruct the parachute portions of the flight. Aerodynamic or parachute parameters are adjusted in the simulation until the prediction reasonably matches the flight trajectory. Knowledge of the static aerodynamics is critical in the CPAS project because the parachute riser load measurements are scaled based on forebody drag. PTV dynamic damping is critical because the vehicle has no reaction control system to maintain attitude - the vehicle dynamics must be understood and modeled correctly before flight. It will be shown here that aerodynamic reconstruction has successfully contributed to the CPAS project.

  16. Applying fiber optical methods for toxicological testing in vitro

    NASA Astrophysics Data System (ADS)

    Maerz, Holger K.; Buchholz, Rainer; Emmrich, Frank; Fink, Frank; Geddes, Clive L.; Pfeifer, Lutz; Raabe, Ferdinand; Scheper, Thomas-Helmut; Ulrich, Elizabeth; Marx, Uwe

    1999-04-01

    The new medical developments, e.g. immune therapy, patient oriented chemotherapy or even gene therapy, create a questionable doubt to the further requirement of animal test. Instead the call for humanitarian reproductive in vitro models becomes increasingly louder. Pharmaceutical usage of in vitro has a long proven history. In cancer research and therapy, the effect of chemostatica in vitro in the so-called oncobiogram is being tested; but the assays do not always correlate with in vivo-like drug resistance and sensitivity. We developed a drug test system in vitro, feasible for therapeutic drug monitoring by the combination of tissue cultivation in hollow fiber bioreactors and fiber optic sensors for monitoring the pharmaceutical effect. Using two fiber optic sensors - an optical oxygen sensor and a metabolism detecting Laserfluoroscope, we were able to successfully monitor the biological status of tissue culture and the drug or toxic effects of in vitro pharmaceutical testing. Furthermore, we developed and patented a system for monitoring the effect of minor toxic compounds which can induce Sick Building Syndrome.

  17. Test Structures Applied to the Rapid Prototyping of Sensors

    NASA Technical Reports Server (NTRS)

    Buehler, M.; Chang, L-J.; Martin, D.

    1997-01-01

    Recently, test structures were used to aid in the rapid development of a gas sensor and pressure sensor. These sensors were fabricated using co-fired ceramic technology and a multiproject approach. This talk will describe results obtained from a ceramic substrate which contained 36 chips with six variants including the sensors, process control monitors, and an interconnect chip. As far as the authors know, this is the first implementation of multi-projects in co-fired ceramic substrate. The gas sensor is being developed for the Space Shuttle and the pressure gage is being developed as a Martian barometer.

  18. Advanced Background Subtraction Applied to Aeroacoustic Wind Tunnel Testing

    NASA Technical Reports Server (NTRS)

    Bahr, Christopher J.; Horne, William C.

    2015-01-01

    An advanced form of background subtraction is presented and applied to aeroacoustic wind tunnel data. A variant of this method has seen use in other fields such as climatology and medical imaging. The technique, based on an eigenvalue decomposition of the background noise cross-spectral matrix, is robust against situations where isolated background auto-spectral levels are measured to be higher than levels of combined source and background signals. It also provides an alternate estimate of the cross-spectrum, which previously might have poor definition for low signal-to-noise ratio measurements. Simulated results indicate similar performance to conventional background subtraction when the subtracted spectra are weaker than the true contaminating background levels. Superior performance is observed when the subtracted spectra are stronger than the true contaminating background levels. Experimental results show limited success in recovering signal behavior for data where conventional background subtraction fails. They also demonstrate the new subtraction technique's ability to maintain a proper coherence relationship in the modified cross-spectral matrix. Beam-forming and de-convolution results indicate the method can successfully separate sources. Results also show a reduced need for the use of diagonal removal in phased array processing, at least for the limited data sets considered.

  19. Effect of day length on germination of seeds collected in Alaska

    USGS Publications Warehouse

    Densmore, R.V.

    1997-01-01

    Day length control can effectively limit seed germination to favorable seasons, but this phenomenon has been studied in relatively few wild plants. I tested species from interior Alaska for day length control of germination under controlled conditions, and I also monitored germination phenology in natural habitats. Unstratified and cold-stratified seeds were germinated on short (13 h) and long (22 h) day length and in the dark at constant and alternating temperatures. On long day length, unstratified Ledum decumbens and Saxifraga tricuspidata seeds germinated from 5??C to 20??C, but on short day length few or no seeds germinated at 5??C and 10??C and germination was reduced at higher temperatures. Unstratified seeds of Diapensia lapponica and Chamaedaphne calyculata germinated only at 15??C and 20??C on long day length, and short day length completely inhibited germination. Cold stratification widened the temperature range for germination on both long and short day lengths, but germination was still lower on short than long day length. Germination phenology in natural habitats was consistent with germination in controlled conditions. In these species, short day length and low temperatures interact to inhibit germination in the fall. After overwintering, seeds germinate in the spring at low temperatures and on long day lengths. The inhibitory effect of short day length is not important in the spring because day length is already long at snowmelt.

  20. When the FRAX® test is applied to controlled clinical trials

    PubMed Central

    Fiore, Carmelo Erio; Gaudio, Agostino

    2012-01-01

    Summary FRAX® is a computer-based algorithm developed by the World Health Organization Collaborating Centre for Metabolic Bone Diseases in Sheffield (UK). This algorithm calculates fracture probability from easily obtained clinical risk factors in men and women: age, sex, body mass index and dichotomized variables comprising prior fragility fracture, parental history of hip fracture, current tobacco smoking, use of long-term oral glucocorticoid, rheumatoid arthritis, other causes of secondary osteoporosis and high alcohol consumption (femoral neck bone mineral density can be optionally input to enhance fracture risk prediction). The output of FRAX® is the 10-year probability of a major osteoporotic fracture (hip, clinical spine, humerus or wrist fracture) and the 10-year probability of hip fracture. Recently various Authors have re-evaluated the effectiveness of drugs approved for postmenopausal osteoporosis to test whether they are more effective in women with higher FRAX® probabilities. PMID:23289024

  1. Effects of soil quality and depth on seed germination and seedling survival at the Nevada test site

    SciTech Connect

    Blomquist, K.W.; Lyon, G.E.

    1993-12-31

    The Nuclear Waste Policy Act, as amended in 1987, directs the US Department of Energy (DOE) to study Yucca Mountain, in southern Nevada, as a potential site for long-term storage of high-level nuclear waste. DOE policy mandates the restoration of all lands disturbed by site characterization activities and DOE has developed an environmental program that is to be implemented during site characterization activities at Yucca.Mountain. DOE is currently conducting reclamation feasibility trials as part of this environmental program. No topsoil was saved on disturbances during early site investigation and minimal soil remains at existing disturbances on Yucca Mountain. A study was developed to test the effects of soil quality and depth on seedling emergence and survival. A series of plots was established and two treatments were tested. The first treatment compared native topsoil to subsoil imported from a borrow pit. The second treatment compared four different depth ranges of both soil types. All plots received identical seeding treatments. Seedling density was measured after emergence. Overall seedling densities were low, averaging 10.3 {plus_minus} 8.8 (SD) plants/m{sup 2}. Statistical analysis revealed a significant interaction between the two treatment factors. The subsoil had increasing densities from the deep soil depths to the shallow depths while the topsoil had increasing densities from the shallow soil depths to the deep depths. The cause of this interaction may have resulted from the bedrock being close to the soil surface of the shallow plots.

  2. Evaluation of strategy for testing thyroid function applied to hypothyroidism.

    PubMed Central

    Corns, C M; Miller, A L

    1986-01-01

    A strategy for testing thyroid function with discretionary assay of thyroid stimulating hormone (TSH) following initial measurement of total plasma thyroxine (tT4) was retrospectively evaluated in relation to the diagnosis of primary hypothyroidism. Over a two year period 14 641 tT4 assays were done and 6887 TSH assays, of which 29% were initiated in the laboratory. The percentage of raised TSH values (over 5 mU/1) was similar to those for clinician and pathologist initiated requests (23.2% and 23.6%). Some TSH requests (1620) were cancelled; when 212 of these were subsequently analysed the TSH value was raised in 5.7% The incidence of raised TSH values in 188 patients with a tT4 below 100 nmol/1 (7.8 micrograms/100 ml), in whom TSH was not requested, was 5.3% Most of these raised TSH results could be readily explained by information available to the requesting clinician but not given on the request form. PMID:3082940

  3. Bioaccumulation tests applied in whole effluent assessment: A review

    SciTech Connect

    De Maagd, P.G.J.

    2000-01-01

    Until recently, the emphasis within whole effluent assessment has been on the application of bioassays for acute and chronic toxicity. Although the need for additional parameters to assess the ecotoxicological hazard and risk of effluents for receiving water systems has been repeatedly advocated, other parameters such as bioaccumulation, genotoxicity, sediment toxicity, and nutrient impacts are seldom addressed. This paper discusses the potential additional value of including bioaccumulation parameters in whole effluent assessment and methods that can be used for routine assessment. It is concluded that screening on the presence of potentially bioaccumulating compounds leads to a more comprehensive hazard assessment and should therefore be included in whole effluent assessment. A chemical method to assess potentially bioaccumulating substances (PBSs) is preferred above methods using organisms or classical group parameters such as extractable organic halogens (EOX). In situ studies with organisms are not feasible for routine assessment for a number of reasons, including cost efficiency and matrix problems. Classical group parameters such as EOX do not relate to bioaccumulation or toxicity. Chemical methods for assessing bioaccumulation are usually presented as integrated methods composed of different procedure steps such as pretreatment, extraction, separation, and detection. However, an optimal method may be constructed by combining procedure steps from different reported methods. Solid phase microextraction combined with high performance liquid chromatography or gas chromatography combined with mass spectrometry is regarded as the preferable method for the assessment of PBSs. Before implementation in whole effluent assessment, however, the method must be carefully validated. Hazard assessment based on bioaccumulation seems feasible. For risk assessment, however, additional information is a prerequisite. Quantitative causal relationships between test assay results

  4. 40 CFR 1051.510 - What special provisions apply for testing ATV engines? [Reserved

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false What special provisions apply for testing ATV engines? 1051.510 Section 1051.510 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Procedures § 1051.510 What special provisions apply for testing ATV engines?...

  5. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Germination of vegetable seed in containers of 1 pound... (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.29 Germination of... the percentage of germination and date of test. Each variety of vegetable seed which has a...

  6. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Germination of vegetable seed in containers of 1 pound... (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.29 Germination of... the percentage of germination and date of test. Each variety of vegetable seed which has a...

  7. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false Germination of vegetable seed in containers of 1 pound... (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.29 Germination of... the percentage of germination and date of test. Each variety of vegetable seed which has a...

  8. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Germination of vegetable seed in containers of 1 pound... (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.29 Germination of... the percentage of germination and date of test. Each variety of vegetable seed which has a...

  9. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 3 2014-01-01 2014-01-01 false Germination of vegetable seed in containers of 1 pound... (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.29 Germination of... the percentage of germination and date of test. Each variety of vegetable seed which has a...

  10. Involvement of Coat Proteins in Bacillus subtilis Spore Germination in High-Salinity Environments.

    PubMed

    Nagler, Katja; Setlow, Peter; Reineke, Kai; Driks, Adam; Moeller, Ralf

    2015-10-01

    The germination of spore-forming bacteria in high-salinity environments is of applied interest for food microbiology and soil ecology. It has previously been shown that high salt concentrations detrimentally affect Bacillus subtilis spore germination, rendering this process slower and less efficient. The mechanistic details of these salt effects, however, remained obscure. Since initiation of nutrient germination first requires germinant passage through the spores' protective integuments, the aim of this study was to elucidate the role of the proteinaceous spore coat in germination in high-salinity environments. Spores lacking major layers of the coat due to chemical decoating or mutation germinated much worse in the presence of NaCl than untreated wild-type spores at comparable salinities. However, the absence of the crust, the absence of some individual nonmorphogenetic proteins, and the absence of either CwlJ or SleB had no or little effect on germination in high-salinity environments. Although the germination of spores lacking GerP (which is assumed to facilitate germinant flow through the coat) was generally less efficient than the germination of wild-type spores, the presence of up to 2.4 M NaCl enhanced the germination of these mutant spores. Interestingly, nutrient-independent germination by high pressure was also inhibited by NaCl. Taken together, these results suggest that (i) the coat has a protective function during germination in high-salinity environments; (ii) germination inhibition by NaCl is probably not exerted at the level of cortex hydrolysis, germinant accessibility, or germinant-receptor binding; and (iii) the most likely germination processes to be inhibited by NaCl are ion, Ca(2+)-dipicolinic acid, and water fluxes. PMID:26187959

  11. Involvement of Coat Proteins in Bacillus subtilis Spore Germination in High-Salinity Environments

    PubMed Central

    Nagler, Katja; Setlow, Peter; Reineke, Kai; Driks, Adam

    2015-01-01

    The germination of spore-forming bacteria in high-salinity environments is of applied interest for food microbiology and soil ecology. It has previously been shown that high salt concentrations detrimentally affect Bacillus subtilis spore germination, rendering this process slower and less efficient. The mechanistic details of these salt effects, however, remained obscure. Since initiation of nutrient germination first requires germinant passage through the spores' protective integuments, the aim of this study was to elucidate the role of the proteinaceous spore coat in germination in high-salinity environments. Spores lacking major layers of the coat due to chemical decoating or mutation germinated much worse in the presence of NaCl than untreated wild-type spores at comparable salinities. However, the absence of the crust, the absence of some individual nonmorphogenetic proteins, and the absence of either CwlJ or SleB had no or little effect on germination in high-salinity environments. Although the germination of spores lacking GerP (which is assumed to facilitate germinant flow through the coat) was generally less efficient than the germination of wild-type spores, the presence of up to 2.4 M NaCl enhanced the germination of these mutant spores. Interestingly, nutrient-independent germination by high pressure was also inhibited by NaCl. Taken together, these results suggest that (i) the coat has a protective function during germination in high-salinity environments; (ii) germination inhibition by NaCl is probably not exerted at the level of cortex hydrolysis, germinant accessibility, or germinant-receptor binding; and (iii) the most likely germination processes to be inhibited by NaCl are ion, Ca2+-dipicolinic acid, and water fluxes. PMID:26187959

  12. Germination of Candida albicans induced by proline.

    PubMed Central

    Dabrowa, N; Taxer, S S; Howard, D H

    1976-01-01

    Blastospores of Candida albicans germinated in proline-biotin-buffer medium incubated at 37 C. Certain other amino acids in the glatamate, asparate, and pyruvate families also fostered germinaton but generally to a lesser extent than did proline. L-Cysteine, D-proline, and certain structural analogues of L-proline inhibited proline-stimualted germination. The concentration of phosphate and glucose was crucial to amino acid-stimulated germination of C. albicans. Clinical isolates and stock cultures varied in their response to the germ tube-inducing activity of proline or other amino acids. The proline-buffer medium cannot be used in a diagnostic test for production of germ tubes by isolates of yeasts. PMID:5375

  13. Approaches to Language Testing. Advances in Language Testing Series: 2. Papers in Applied Linguistics.

    ERIC Educational Resources Information Center

    Spolsky, Bernard, Ed.

    This volume, one in a series on modern language testing, collects four essays dealing with current approaches to lanquage testing. The introduction traces the development of language testing theory and examines the role of linguistics in this area. "The Psycholinguistic Basis," by E. Ingram, discusses some interpretations of the term…

  14. Physical characterization of Rhipsalis (Cactaceae) fruits and seeds germination in different temperatures and light regimes.

    PubMed

    Lone, A B; Colombo, R C; Andrade, B L G; Takahashi, L S A; Faria, R T

    2016-06-01

    The germination characteristics of the native cactus species are poorly known, being the temperature and the light the factors that the most interferes in that process. Thus, the objective of the present work was to characterize the fruits and evaluate the influence of the temperature and the light in the seed germination of Rhipsalis floccosa, Rhipsalis pilocarpa and Rhipsalis teres. The tested constant temperatures were 15, 20, 25, 30 and 35 °C and the alternate of 20-30 °C and 25-35 °C in a photoperiod of 10 hours, and with determination of the most appropriate temperature, the germination was tested in light absence. The germination percentage, the index of germination speed and medium time of germination were evaluated. For R. floccosa, the highest germination percentage was at 20 °C. For R. pilocarpa and R. teres, the highest germination percentages occurred in 15 °C and 20 °C. There was correlation to germination percentage between the three species, indicating that they had similar germination behavior. Total absence of germination was verified for the three species in condition of light absence. In conclusion, the temperature of 20 °C is the most suitable for the seed germination of R. floccosa. For the species R. pilocarpa and R. teres, the temperatures of 15 and 20 °C are the most suitable. PMID:26934150

  15. Guidelines for efficacy testing of insecticides for indoor and outdoor ground-applied space spray applications.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This document provides specific and standardized procedures and criteria for efficacy testing and evaluation of insecticides for indoor and outdoor, ground-applied space spray applications against vectors and pests of public health importance....

  16. Applied Physics Modules: Notes, Instructions, Data Sheets, Tests, and Test Answer Keys.

    ERIC Educational Resources Information Center

    Southeast Community Coll., Lincoln, NE.

    These user instructions and related materials are designed to accompany a series of twenty-three applied physics modules which have been developed for postsecondary students in electrical, electronics, machine tool, metals, manufacturing, automotive, diesel, architecture, and civil drafting occupational programs. The instructions include an…

  17. Engineering in software testing: statistical testing based on a usage model applied to medical device development.

    PubMed

    Jones, P L; Swain, W T; Trammell, C J

    1999-01-01

    When a population is too large for exhaustive study, as is the case for all possible uses of a software system, a statistically correct sample must be drawn as a basis for inferences about the population. A Markov chain usage model is an engineering formalism that represents the population of possible uses for which a product is to be tested. In statistical testing of software based on a Markov chain usage model, the rich body of analytical results available for Markov chains provides numerous insights that can be used in both product development and test planing. A usage model is based on specifications rather than code, so insights that result from model building can inform product decisions in the early stages of a project when the opportunity to prevent problems is the greatest. Statistical testing based on a usage model provides a sound scientific basis for quantifying the reliability of software. PMID:10459417

  18. Field Test of Fiber-Optic Voltage and Current Sensors Applied to Gas Insulated Substation

    NASA Astrophysics Data System (ADS)

    Kuroda, Y.; Abe, Y.; Kuwahara, H.; Yoshinaga, K.

    1986-08-01

    The fiber-optic voltage and current sensors applied for 84kV three phase type gas insulated substation (GIS) were tested in order to see the advantages of these sensors practically in adverse field condition. The application technologies and field endurance test results of the sensors are described in this paper.

  19. Applying Bayesian Item Selection Approaches to Adaptive Tests Using Polytomous Items

    ERIC Educational Resources Information Center

    Penfield, Randall D.

    2006-01-01

    This study applied the maximum expected information (MEI) and the maximum posterior-weighted information (MPI) approaches of computer adaptive testing item selection to the case of a test using polytomous items following the partial credit model. The MEI and MPI approaches are described. A simulation study compared the efficiency of ability…

  20. LPT. Shield test facility (TAN646) interior. Construction worker applies caulking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LPT. Shield test facility (TAN-646) interior. Construction worker applies caulking compound to joint between stainless steel weir and concrete. Photographer: Jack L. Anderson. Date: March 6, 1959. INEEL negative no. 59-1099 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID

  1. 41 CFR 300-80.3 - What must be done to apply for test program authority?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false What must be done to apply for test program authority? 300-80.3 Section 300-80.3 Public Contracts and Property Management Federal Travel Regulation System GENERAL AGENCY REQUIREMENTS 80-RELOCATION EXPENSES TEST PROGRAMS §...

  2. A Multivariate Randomization Text of Association Applied to Cognitive Test Results

    NASA Technical Reports Server (NTRS)

    Ahumada, Albert; Beard, Bettina

    2009-01-01

    Randomization tests provide a conceptually simple, distribution-free way to implement significance testing. We have applied this method to the problem of evaluating the significance of the association among a number (k) of variables. The randomization method was the random re-ordering of k-1 of the variables. The criterion variable was the value of the largest eigenvalue of the correlation matrix.

  3. Pre-treating Seed to Enhance Germination of Desert Shrubs

    SciTech Connect

    W. K. Ostler; D. C. Anderson; D. J. Hansen

    2002-06-01

    Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.

  4. Applying EVM to Satellite on Ground and In-Orbit Testing - Better Data in Less Time

    NASA Technical Reports Server (NTRS)

    Peters, Robert; Lebbink, Elizabeth-Klein; Lee, Victor; Model, Josh; Wezalis, Robert; Taylor, John

    2008-01-01

    Using Error Vector Magnitude (EVM) in satellite integration and test allows rapid verification of the Bit Error Rate (BER) performance of a satellite link and is particularly well suited to measurement of low bit rate satellite links where it can result in a major reduction in test time (about 3 weeks per satellite for the Geosynchronous Operational Environmental Satellite [GOES] satellites during ground test) and can provide diagnostic information. Empirical techniques developed to predict BER performance from EVM measurements and lessons learned about applying these techniques during GOES N, O, and P integration test and post launch testing, are discussed.

  5. Effects of germination season on life history traits and on transgenerational plasticity in seed dormancy in a cold desert annual

    PubMed Central

    Lu, Juan J.; Tan, Dun Y.; Baskin, Carol C.; Baskin, Jerry M.

    2016-01-01

    The maternal environment can influence the intensity of seed dormancy and thus seasonal germination timing and post-germination life history traits. We tested the hypotheses that germination season influences phenotypic expression of post-germination life history traits in the cold desert annual Isatis violascens and that plants from autumn- and spring-germinating seeds produce different proportions of seeds with nondeep and intermediate physiological dormancy (PD). Seeds were sown in summer and flexibility in various life history traits determined for plants that germinated in autumn and in spring. A higher percentage of spring- than of autumn-germinating plants survived the seedling stage, and all surviving plants reproduced. Number of silicles increased with plant size (autumn- > spring-germinating plants), whereas percent dry mass allocated to reproduction was higher in spring- than in autumn-germinating plants. Autumn-germinating plants produced proportionally more seeds with intermediate PD than spring-germinating plants, while spring-germinating plants produced proportionally more seeds with nondeep PD than autumn-germinating plants. Flexibility throughout the life history and transgenerational plasticity in seed dormancy are adaptations of I. violascens to its desert habitat. Our study is the first to demonstrate that autumn- and spring-germinating plants in a species population differ in proportion of seeds produced with different levels of PD. PMID:27117090

  6. Effects of germination season on life history traits and on transgenerational plasticity in seed dormancy in a cold desert annual.

    PubMed

    Lu, Juan J; Tan, Dun Y; Baskin, Carol C; Baskin, Jerry M

    2016-01-01

    The maternal environment can influence the intensity of seed dormancy and thus seasonal germination timing and post-germination life history traits. We tested the hypotheses that germination season influences phenotypic expression of post-germination life history traits in the cold desert annual Isatis violascens and that plants from autumn- and spring-germinating seeds produce different proportions of seeds with nondeep and intermediate physiological dormancy (PD). Seeds were sown in summer and flexibility in various life history traits determined for plants that germinated in autumn and in spring. A higher percentage of spring- than of autumn-germinating plants survived the seedling stage, and all surviving plants reproduced. Number of silicles increased with plant size (autumn- > spring-germinating plants), whereas percent dry mass allocated to reproduction was higher in spring- than in autumn-germinating plants. Autumn-germinating plants produced proportionally more seeds with intermediate PD than spring-germinating plants, while spring-germinating plants produced proportionally more seeds with nondeep PD than autumn-germinating plants. Flexibility throughout the life history and transgenerational plasticity in seed dormancy are adaptations of I. violascens to its desert habitat. Our study is the first to demonstrate that autumn- and spring-germinating plants in a species population differ in proportion of seeds produced with different levels of PD. PMID:27117090

  7. Germination of Chenopodium Album in Response to Microwave Plasma Treatment

    NASA Astrophysics Data System (ADS)

    Será, Bozena; Stranák, Vitezslav; Serý, Michal; Tichý, Milan; Spatenka, Petr

    2008-08-01

    The seeds of Lamb's Quarters (Chenopodium album agg.) were stimulated by low-pressure discharge. The tested seeds were exposed to plasma discharge for different time durations (from 6 minutes to 48 minutes). Germination tests were performed under specified laboratory conditions during seven days in five identical and completely independent experiments. Significant differences between the control and plasma-treated seeds were observed. The treated seeds showed structural changes on the surface of the seat coat. They germinated faster and their sprout accretion on the first day of seed germination was longer. Germination rate for the untreated seeds was 15% while it increased approximately three times (max 55%) for seeds treated by plasma from 12 minutes to 48 minutes.

  8. Intersection of two signalling pathways: extracellular nucleotides regulate pollen germination and pollen tube growth via nitric oxide

    PubMed Central

    Reichler, Stuart A.; Torres, Jonathan; Rivera, Amy L.; Cintolesi, Viviana A.; Clark, Greg; Roux, Stanley J.

    2009-01-01

    Plant and animal cells release or secrete ATP by various mechanisms, and this activity allows extracellular ATP to serve as a signalling molecule. Recent reports suggest that extracellular ATP induces plant responses ranging from increased cytosolic calcium to changes in auxin transport, xenobiotic resistance, pollen germination, and growth. Although calcium has been identified as a secondary messenger for the extracellular ATP signal, other parts of this signal transduction chain remain unknown. Increasing the extracellular concentration of ATPγS, a poorly-hydrolysable ATP analogue, inhibited both pollen germination and pollen tube elongation, while the addition of AMPS had no effect. Because pollen tube elongation is also sensitive to nitric oxide, this raised the possibility that a connection exists between the two pathways. Four approaches were used to test whether the germination and growth effects of extracellular ATPγS were transduced via nitric oxide. The results showed that increases in extracellular ATPγS induced increases in cellular nitric oxide, chemical agonists of the nitric oxide signalling pathway lowered the threshold of extracellular ATPγS that inhibits pollen germination, an antagonist of guanylate cyclase, which can inhibit some nitric oxide signalling pathways, blocked the ATPγS-induced inhibition of both pollen germination and pollen tube elongation, and the effects of applied ATPγS were blocked in nia1nia2 mutants, which have diminished NO production. The concurrence of these four data sets support the conclusion that the suppression of pollen germination and pollen tube elongation by extracellular nucleotides is mediated in part via the nitric oxide signalling pathway. PMID:19363208

  9. Case Studies for the Statistical Design of Experiments Applied to Powered Rotor Wind Tunnel Tests

    NASA Technical Reports Server (NTRS)

    Overmeyer, Austin D.; Tanner, Philip E.; Martin, Preston B.; Commo, Sean A.

    2015-01-01

    The application of statistical Design of Experiments (DOE) to helicopter wind tunnel testing was explored during two powered rotor wind tunnel entries during the summers of 2012 and 2013. These tests were performed jointly by the U.S. Army Aviation Development Directorate Joint Research Program Office and NASA Rotary Wing Project Office, currently the Revolutionary Vertical Lift Project, at NASA Langley Research Center located in Hampton, Virginia. Both entries were conducted in the 14- by 22-Foot Subsonic Tunnel with a small portion of the overall tests devoted to developing case studies of the DOE approach as it applies to powered rotor testing. A 16-47 times reduction in the number of data points required was estimated by comparing the DOE approach to conventional testing methods. The average error for the DOE surface response model for the OH-58F test was 0.95 percent and 4.06 percent for drag and download, respectively. The DOE surface response model of the Active Flow Control test captured the drag within 4.1 percent of measured data. The operational differences between the two testing approaches are identified, but did not prevent the safe operation of the powered rotor model throughout the DOE test matrices.

  10. Photoinhibition of germination in grass seed--implications for prairie revegetation.

    PubMed

    Mollard, Federico P O; Naeth, M Anne

    2014-09-01

    Germination photoinhibition is not a recognized cause of revegetation failure; yet prolonged sunlight exposure can inhibit germination of several grass species. This research addressed susceptibility to photoinhibition of selected native grass species used to restore Canadian prairies, and reclamation treatments to alter environmental conditions in order to release seeds from photoinhibition. Under laboratory conditions effects of photoinhibition were tested on the ability of seeds to germinate at low water potential and effects of daily alternating temperatures and nitrates to break photoinhibition. Whether surficial mulch can release seeds from photoinhibition was assessed in a field experiment. Germination photoinhibition was evident in Festuca hallii and Koeleria macrantha seeds even under very low irradiances. The prolonged exposure to light decreased germination rates and ability of seeds to germinate at low water potentials. Daily fluctuating temperatures released a fraction of Bromus carinatus and Elymus trachycaulus seeds from photoinhibition yet did not improve F. hallii or K. macrantha germinability. Nitrates failed to break seed photoinhibition in all species tested. In the field experiment, mulched F. hallii seeds (covered with an erosion control blanket) showed a tenfold increase in germination percentages relative to seeds exposed to direct sunlight, indicating the facilitative effects of mulching on attenuation of the light environment. We conclude that germination photoinhibition as a cause of emergence failures in land reclamation where seed is broadcast or shallow seeded should be recognized and germination photoinhibition included in the decision making process to select revegetation seeding techniques. PMID:24794519

  11. Acquisition, simulation, and test replication of weapon firing shock applied to optical sights

    NASA Astrophysics Data System (ADS)

    Ball, Kenneth D.; Gardner, Dave

    2011-09-01

    With the ever increasing desire for range and delivery capabilities of ballistic defence equipment, weapons and sight systems are constantly evolving in complexity. As a result current systems now incorporate more sophisticated technology than ever before. This paper describes the non-intrusive mechanical field data acquisition and subsequent analysis and test integration techniques performed on complex opto-mechanical weapon mounted systems. As a result of physical acquisition, innovative techniques have been developed to enable the synthesis of the transient recordings for the purpose of finite element analysis. Further investigations have revealed new possibilities in applying more accurately controlled 'in house' loads, for low cost representative test purposes.

  12. Germination characteristics of six plant species growing on the Hanford Site. [Disturbed land revegetation feasibility studies

    SciTech Connect

    Cox, G.R.; Kirkham, R.R.; Cline, J.F.

    1980-03-01

    Six plant species (Siberian and thickspike wheatgrass, cheatgrass, sand dropseed, Indian ricegrass, and Russian thistle) found on the Hanford Site were studied as part of an investigation into the revegetation of disturbed areas. Germination response to three environmental parameters (soil moisture, soil temperature, and planting depth) were measured. Results indicated that when a polyethylene glycol solution was used to control the osmotic potential of the imbibition media, no significant decrease in germination rate occurred down to -3.0 bars. However, below -7.0 bars all species experienced a decrease in germination. When germinated in soil, all species except Russian thistle exhibited a significant decrease in germination rate at -0.3 bars. Russian thistle was the only species tested that exhibited germination at a soil temperature of 1/sup 0/C. All species gave optimum germination at temperatures between 10 and 15/sup 0/C. Thickspike wheatgrass was the only species tested which was able to germinate and emerge from a planting depth of greater than 2 inches. If supplemental moisture is provided, a shallow planting would be advisable for those species tested. If not overcome by pretreatment prior to planting, seed dormancy may be a significant factor which will reduce the germination potential of some species tested.

  13. Comparison of infrared and 3D digital image correlation techniques applied for mechanical testing of materials

    NASA Astrophysics Data System (ADS)

    Krstulović-Opara, Lovre; Surjak, Martin; Vesenjak, Matej; Tonković, Zdenko; Kodvanj, Janoš; Domazet, Željko

    2015-11-01

    To investigate the applicability of infrared thermography as a tool for acquiring dynamic yielding in metals, a comparison of infrared thermography with three dimensional digital image correlation has been made. Dynamical tension tests and three point bending tests of aluminum alloys have been performed to evaluate results obtained by IR thermography in order to detect capabilities and limits for these two methods. Both approaches detect pastification zone migrations during the yielding process. The results of the tension test and three point bending test proved the validity of the IR approach as a method for evaluating the dynamic yielding process when used on complex structures such as cellular porous materials. The stability of the yielding process in the three point bending test, as contrary to the fluctuation of the plastification front in the tension test, is of great importance for the validation of numerical constitutive models. The research proved strong performance, robustness and reliability of the IR approach when used to evaluate yielding during dynamic loading processes, while the 3D DIC method proved to be superior in the low velocity loading regimes. This research based on two basic tests, proved the conclusions and suggestions presented in our previous research on porous materials where middle wave infrared thermography was applied.

  14. Factors influencing seed germination of medicinal plant Salvia aegyptiaca L. (Lamiaceae)

    PubMed Central

    Gorai, Mustapha; Gasmi, Hayet; Neffati, Mohamed

    2011-01-01

    Salvia aegyptiaca is a xerophytic perennial herb belongs to the Lamiaceae family commonly used for medicinal purposes. Laboratory experiments were carried out to assess the effects of temperature and salinity on seed germination and recovery responses after transferring to distilled water. Temperatures between 10 and 40 °C seem to be favourable for the germination of this species. Germination was inhibited by either an increase or decrease in temperature from the optimum (30 °C). The highest germination percentages were obtained at 0 mM NaCl; however, the increase of solution osmolalities progressively inhibited seed germination. The germination rate decreased with an increase in salinity for most of tested temperatures, but comparatively higher rates were obtained at 30 °C. Salt stress decreased both the percentage and the rate of germination. An interaction between salinity and temperature yielded no germination at 300 mM NaCl. By experimental transfer to distilled water, S. aegyptiaca seeds that were exposed to moderately saline conditions recovered and keep their ability to germinate mostly at low temperatures. At 300 mM NaCl, germination recovery decreased with increasing temperature and it was completely inhibited at 40 °C. PMID:23961132

  15. Factors influencing seed germination of medicinal plant Salvia aegyptiaca L. (Lamiaceae).

    PubMed

    Gorai, Mustapha; Gasmi, Hayet; Neffati, Mohamed

    2011-07-01

    Salvia aegyptiaca is a xerophytic perennial herb belongs to the Lamiaceae family commonly used for medicinal purposes. Laboratory experiments were carried out to assess the effects of temperature and salinity on seed germination and recovery responses after transferring to distilled water. Temperatures between 10 and 40 °C seem to be favourable for the germination of this species. Germination was inhibited by either an increase or decrease in temperature from the optimum (30 °C). The highest germination percentages were obtained at 0 mM NaCl; however, the increase of solution osmolalities progressively inhibited seed germination. The germination rate decreased with an increase in salinity for most of tested temperatures, but comparatively higher rates were obtained at 30 °C. Salt stress decreased both the percentage and the rate of germination. An interaction between salinity and temperature yielded no germination at 300 mM NaCl. By experimental transfer to distilled water, S. aegyptiaca seeds that were exposed to moderately saline conditions recovered and keep their ability to germinate mostly at low temperatures. At 300 mM NaCl, germination recovery decreased with increasing temperature and it was completely inhibited at 40 °C. PMID:23961132

  16. Impact of gene patents on diagnostic testing: a new patent landscaping method applied to spinocerebellar ataxia

    PubMed Central

    Berthels, Nele; Matthijs, Gert; Van Overwalle, Geertrui

    2011-01-01

    Recent reports in Europe and the United States raise concern about the potential negative impact of gene patents on the freedom to operate of diagnosticians and on the access of patients to genetic diagnostic services. Patents, historically seen as legal instruments to trigger innovation, could cause undesired side effects in the public health domain. Clear empirical evidence on the alleged hindering effect of gene patents is still scarce. We therefore developed a patent categorization method to determine which gene patents could indeed be problematic. The method is applied to patents relevant for genetic testing of spinocerebellar ataxia (SCA). The SCA test is probably the most widely used DNA test in (adult) neurology, as well as one of the most challenging due to the heterogeneity of the disease. Typically tested as a gene panel covering the five common SCA subtypes, we show that the patenting of SCA genes and testing methods and the associated licensing conditions could have far-reaching consequences on legitimate access to this gene panel. Moreover, with genetic testing being increasingly standardized, simply ignoring patents is unlikely to hold out indefinitely. This paper aims to differentiate among so-called ‘gene patents' by lifting out the truly problematic ones. In doing so, awareness is raised among all stakeholders in the genetic diagnostics field who are not necessarily familiar with the ins and outs of patenting and licensing. PMID:21811306

  17. In Vitro Pollen Viability and Pollen Germination in Cherry Laurel (Prunus laurocerasus L.)

    PubMed Central

    Sulusoglu, Melekber; Cavusoglu, Aysun

    2014-01-01

    Pollen quality is important for growers and breeders. This study was carried out to determine in vitro pollen viability and pollen germination in seven genotypes of cherry laurel (Prunus laurocerasus L.). Two pollen viability tests, TTC (2,3,5-triphenyl tetrazolium chloride) and IKI (iodine potassium iodide), were used. Pollen traits of genotypes were studied using an in vitro medium containing 0%, 5%, 10%, 15%, and 20% sucrose to determine the best sucrose concentrations for germination. In the second step, the germinated pollen was counted 1, 4, 6, 10, 12, 24, and 48 hours later until there was no further germination. The viability rates were different according to genotypes and tests used. The IKI and TTC staining tests and pollen germination had low correlation (r2 = 0.0614 and r2 = 0.0015, resp.). Painted pollen rate was higher and pollen was well-stained with IKI test and pollen viability estimated with TTC staining test was better than that estimated with the IKI staining test. 15% sucrose gave the best germination rates in most of the genotypes. Pollen germination rates were recorded periodically from one hour to 48 hours in 15% sucrose and the results showed that pollen germination rates increased after 6 hours of being placed in culture media. PMID:25405230

  18. Tank Applied Testing of Load-Bearing Multilayer Insulation (LB-MLI)

    NASA Technical Reports Server (NTRS)

    Johnson, Wesley L.; Valenzuela, Juan G.; Feller, Jerr; Plachta, Dave

    2014-01-01

    The development of long duration orbital cryogenic storage systems will require the reduction of heat loads into the storage tank. In the case of liquid hydrogen, complete elimination of the heat load at 20 K is currently impractical due to the limitations in lift available on flight cryocoolers. In order to reduce the heat load, without having to remove heat at 20 K, the concept of Reduced Boil-Off uses cooled shields within the insulation system at approximately 90 K. The development of Load-Bearing Multilayer Insulation (LB-MLI) allowed the 90 K shield with tubing and cryocooler attachments to be suspended within the MLI and still be structurally stable. Coupon testing both thermally and structurally were performed to verify that the LB-MLI should work at the tank applied level. Then tank applied thermal and structural (acoustic) testing was performed to demonstrate the functionality of the LB-MLI as a structural insulation system. The LB-MLI showed no degradation of thermal performance due to the acoustic testing and showed excellent thermal performance when integrated with a 90 K class cryocooler on a liquid hydrogen tank.

  19. Tank Applied Testing of Load-Bearing Multilayer Insulation (LB-MLI)

    NASA Technical Reports Server (NTRS)

    Johnson, Wesley L.; Valenzuela, Juan G.; Feller, Jeffrey R.; Plachta, David W.

    2014-01-01

    The development of long duration orbital cryogenic storage systems will require the reduction of heat loads into the storage tank. In the case of liquid hydrogen, complete elimination of the heat load at 20 K is currently impractical due to the limitations in lift available on flight cryocoolers. In order to reduce the heat load, without having to remove heat at 20 K, the concept of Reduced Boil-Off uses cooled shields within the insulation system at approximately 90 K. The development of Load-Bearing Multilayer Insulation (LB-MLI) allowed the 90 K shield with tubing and cryocooler attachments to be suspended within the MLI and still be structurally stable. Coupon testing, both thermal and structural was performed to verify that the LB-MLI should work at the tank applied level. Then tank applied thermal and structural (acoustic) testing was performed to demonstrate the functionality of the LB-MLI as a structural insulation system. The LB-MLI showed no degradation of thermal performance due to the acoustic testing and showed excellent thermal performance when integrated with a 90 K class cryocooler on a liquid hydrogen tank.

  20. Thorough approach to measurement uncertainty analysis applied to immersed heat exchanger testing

    SciTech Connect

    Farrington, R B; Wells, C V

    1986-04-01

    This paper discusses the value of an uncertainty analysis, discusses how to determine measurement uncertainty, and then details the sources of error in instrument calibration, data acquisition, and data reduction for a particular experiment. Methods are discussed to determine both the systematic (or bias) error in an experiment as well as to determine the random (or precision) error in the experiment. The detailed analysis is applied to two sets of conditions in measuring the effectiveness of an immersed coil heat exchanger. It shows the value of such analysis as well as an approach to reduce overall measurement uncertainty and to improve the experiment. This paper outlines how to perform an uncertainty analysis and then provides a detailed example of how to apply the methods discussed in the paper. The authors hope this paper will encourage researchers and others to become more concerned with their measurement processes and to report measurement uncertainty with all of their test results.

  1. Clinical usefulness of the clock drawing test applying rasch analysis in predicting of cognitive impairment

    PubMed Central

    Yoo, Doo Han; Lee, Jae Shin

    2016-01-01

    [Purpose] This study examined the clinical usefulness of the clock drawing test applying Rasch analysis for predicting the level of cognitive impairment. [Subjects and Methods] A total of 187 stroke patients with cognitive impairment were enrolled in this study. The 187 patients were evaluated by the clock drawing test developed through Rasch analysis along with the mini-mental state examination of cognitive evaluation tool. An analysis of the variance was performed to examine the significance of the mini-mental state examination and the clock drawing test according to the general characteristics of the subjects. Receiver operating characteristic analysis was performed to determine the cutoff point for cognitive impairment and to calculate the sensitivity and specificity values. [Results] The results of comparison of the clock drawing test with the mini-mental state showed significant differences in according to gender, age, education, and affected side. A total CDT of 10.5, which was selected as the cutoff point to identify cognitive impairement, showed a sensitivity, specificity, Youden index, positive predictive, and negative predicive values of 86.4%, 91.5%, 0.8, 95%, and 88.2%. [Conclusion] The clock drawing test is believed to be useful in assessments and interventions based on its excellent ability to identify cognitive disorders. PMID:27512283

  2. Tomato Seed Coat Permeability to Selected Carbon Nanomaterials and Enhancement of Germination and Seedling Growth

    PubMed Central

    Ratnikova, Tatsiana A.; Podila, Ramakrishna; Rao, Apparao M.; Taylor, Alan G.

    2015-01-01

    Seed coat permeability was examined using a model that tested the effects of soaking tomato (Solanum lycopersicon) seeds in combination with carbon-based nanomaterials (CBNMs) and ultrasonic irradiation (US). Penetration of seed coats to the embryo by CBNMs, as well as CBNMs effects on seed germination and seedling growth, was examined. Two CBNMs, C60(OH)20 (fullerol) and multiwalled nanotubes (MWNTs), were applied at 50 mg/L, and treatment exposure ranged from 0 to 60 minutes. Bright field, fluorescence, and electron microscopy and micro-Raman spectroscopy provided corroborating evidence that neither CBNM was able to penetrate the seed coat. The restriction of nanomaterial (NM) uptake was attributed to the semipermeable layer located at the innermost layer of the seed coat adjacent to the endosperm. Seed treatments using US at 30 or 60 minutes in the presence of MWNTs physically disrupted the seed coat; however, the integrity of the semipermeable layer was not impaired. The germination percentage and seedling length and weight were enhanced in the presence of MWNTs but were not altered by C60(OH)20. The combined exposure of seeds to NMs and US provided insight into the nanoparticle-seed interaction and may serve as a delivery system for enhancing seed germination and early seedling growth. PMID:26495423

  3. Biological effects of low energy nitrogen ion implantation on Jatropha curcas L. seed germination

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Wang, Xiao-teng; Gan, Cai-ling; Fang, Yan-qiong; Zhang, Meng

    2012-09-01

    To explore the biological effects of nitrogen ion beam implantation on dry Jatropha curcas seed, a beam of N+ with energy of 25 keV was applied to treat the dry seed at six different doses. N+ beam implantation greatly decreased germination rate and seedling survival rate. The doses within the range of 12 × 1016 to 15 × 1016 ions cm-2 severely damaged the seeds: total antioxidant capacity (TAC), germination rate, seedling survival rate, reduced ascorbate acid (HAsA) and reduced glutathione (GSH) contents, and most of the tested antioxidases activity (i.e. catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD)) reached their lowest levels. At a dose of 18 × 1016 ion cm-2, biological repair took place: moderate increases were found in TAC, germination rate, seedling survival rate, HAsA and GSH contents, and some antioxidant enzyme activities (i.e. CAT, APX, SOD and GPX). The dose of 18 × 1016 ions cm-2 may be the optimum dose for use in dry J. curcas seed mutation breeding. CAT, HAsA and GSH contributed to the increase of TAC, but CAT was the most important. POD performed its important role as seed was severely damaged. The main role of the HAsA-GSH cycle appeared to be for regeneration of HAsA.

  4. Improvement of Subsonic Basic Research Tunnel Flow Quality as Applied to Wall Mounted Testing

    NASA Technical Reports Server (NTRS)

    Howerton, Brian M.

    1995-01-01

    A survey to determine the characteristics of a boundary layer that forms on the wall of the Subsonic Basic Research Tunnel has been performed. Early results showed significant differences in the velocity profiles as measured spanwise across the wall. An investigation of the flow in the upstream contraction revealed the presence of a separation bubble at the beginning of the contraction which caused much of the observed unsteadiness. Vortex generators were successfully applied to the contraction inlet to alleviate the separation. A final survey of the wall boundary layer revealed variations in the displacement and momentum thicknesses to be less than +/- 5% for all but the most upper portion of the wall. The flow quality was deemed adequate to continue the planned follow-on tests to help develop the semi-span test technique.

  5. Frictionless compression testing using load-applying platens made from porous graphite aerostatic bearings

    NASA Astrophysics Data System (ADS)

    El-Aguizy, Tarek; Plante, Jean-Sebastien; Slocum, Alexander H.; Vogan, John D.

    2005-07-01

    In compression testing of soft materials at high strains, friction between a sample and the load-applying platens induces a differential lateral expansion that is visually evident as barreling. Barreling reduces the accuracy of the tests as a means of establishing accurate material properties. Current techniques for reducing friction, which involve liquid squeeze film lubrication, may not achieve true frictionless interfaces, are messy, and may adversely affect some samples. This article examines the use of porous graphite aerostatic bearings as a frictionless testing interface. The physics of a soft material under compressive loading by porous air bearings is investigated with simple finite element analysis and air flow models. An aerostatic bearing assembly is also constructed and compared to other friction reduction techniques. The results of these experiments indicate that there are benefits to using air bearings as they are clean, chemically inert, extremely stiff, reduce friction to levels comparable to existing methods, have negligible squeeze film effect, are repeatable, and allow for cyclic compression testing.

  6. Evaluation of feasibility of static tests applied to Küre VMS ore deposits

    NASA Astrophysics Data System (ADS)

    Demirel, Cansu; Çelik Balci, Nurgül; Şeref Sönmez, M.

    2015-04-01

    Küre volcanogenic massive sulfide (VMS) ore deposits have been mined for its copper content for over centuries. However, there is no published data on AMD around Küre VMS ore deposits. This study investigates the sources of acid producing mechanisms in Küre, using field and laboratorial approaches. Geochemical static tests to predict AMD generation are widely applied to mining sites for assessing potential environmental consequences. However, there are well known limitations of these methods particularly resulting from assumptions used for calculations. To test the feasibility of the methods to predict potential of AMD generation of Küre (VMS) copper deposits, for the first time, acid production and neutralization potential of various mine wastes of Küre (VMS) copper deposits were determined. To test our static test results, in situ and laboratory geochemical data were also obtained from the groundwater discharges from Bakibaba underground mining tunnels. Feasibility study showed that, despite a few inconsistencies, static tests were suitable for predicting generation of AMD around Küre copper mining site and reflected well the site conditions. The current study revealed that pulp density, defined as solid/liquid ratio and used for static tests, is an important limiting factor to predict reliable data for AMD generation. In this study, we also determined surface waters affected by AMD are predicted to have a pH value between 3 and 5, with an average of pH 4. Excessive concentrations of manganese, copper, cobalt and sulfate are also noted with considerable amounts of iron and zinc, which can reach to toxic levels. Moreover, iron and zinc were found to be the controlling the fate of metals by precipitation and co-precipitation, due to their relatively depleted concentrations at redox shifting zones. Key words: Küre pyritic copper ore, Bakibaba mining tunnels, volcanogenic massive sulfide ore deposits, acid production potential, neutralization potential

  7. Applying Computer Adaptive Testing to Optimize Online Assessment of Suicidal Behavior: A Simulation Study

    PubMed Central

    de Vries, Anton LM; de Groot, Marieke H; de Keijser, Jos; Kerkhof, Ad JFM

    2014-01-01

    Background The Internet is used increasingly for both suicide research and prevention. To optimize online assessment of suicidal patients, there is a need for short, good-quality tools to assess elevated risk of future suicidal behavior. Computer adaptive testing (CAT) can be used to reduce response burden and improve accuracy, and make the available pencil-and-paper tools more appropriate for online administration. Objective The aim was to test whether an item response–based computer adaptive simulation can be used to reduce the length of the Beck Scale for Suicide Ideation (BSS). Methods The data used for our simulation was obtained from a large multicenter trial from The Netherlands: the Professionals in Training to STOP suicide (PITSTOP suicide) study. We applied a principal components analysis (PCA), confirmatory factor analysis (CFA), a graded response model (GRM), and simulated a CAT. Results The scores of 505 patients were analyzed. Psychometric analyses showed the questionnaire to be unidimensional with good internal consistency. The computer adaptive simulation showed that for the estimation of elevation of risk of future suicidal behavior 4 items (instead of the full 19) were sufficient, on average. Conclusions This study demonstrated that CAT can be applied successfully to reduce the length of the Dutch version of the BSS. We argue that the use of CAT can improve the accuracy and the response burden when assessing the risk of future suicidal behavior online. Because CAT can be daunting for clinicians and applied scientists, we offer a concrete example of our computer adaptive simulation of the Dutch version of the BSS at the end of the paper. PMID:25213259

  8. Characterization of the Dynamic Germination of Individual Clostridium difficile Spores Using Raman Spectroscopy and Differential Interference Contrast Microscopy

    PubMed Central

    Wang, Shiwei; Shen, Aimee; Setlow, Peter

    2015-01-01

    ABSTRACT The Gram-positive spore-forming anaerobe Clostridium difficile is a leading cause of nosocomial diarrhea. Spores of C. difficile initiate infection when triggered to germinate by bile salts in the gastrointestinal tract. We analyzed germination kinetics of individual C. difficile spores using Raman spectroscopy and differential interference contrast (DIC) microscopy. Similar to Bacillus spores, individual C. difficile spores germinating with taurocholate plus glycine began slow leakage of a ∼15% concentration of a chelate of Ca2+ and dipicolinic acid (CaDPA) at a heterogeneous time T1, rapidly released CaDPA at Tlag, completed CaDPA release at Trelease, and finished peptidoglycan cortex hydrolysis at Tlysis. T1 and Tlag values for individual spores were heterogeneous, but ΔTrelease periods (Trelease − Tlag) were relatively constant. In contrast to Bacillus spores, heat treatment did not stimulate spore germination in the two C. difficile strains tested. C. difficile spores did not germinate with taurocholate or glycine alone, and different bile salts differentially promoted spore germination, with taurocholate and taurodeoxycholate being best. Transient exposure of spores to taurocholate plus glycine was sufficient to commit individual spores to germinate. C. difficile spores did not germinate with CaDPA, in contrast to B. subtilis and C. perfringens spores. However, the detergent dodecylamine induced C. difficile spore germination, and rates were increased by spore coat removal although cortex hydrolysis did not follow Trelease, in contrast with B. subtilis. C. difficile spores lacking the cortex-lytic enzyme, SleC, germinated extremely poorly, and cortex hydrolysis was not observed in the few sleC spores that partially germinated. Overall, these findings indicate that C. difficile and B. subtilis spore germination exhibit key differences. IMPORTANCE Spores of the Gram-positive anaerobe Clostridium difficile are responsible for initiating infection

  9. 75 FR 47592 - Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-06

    ..., 2007 (72 FR 32647) (FRL-8135-9), of national experts in which the revisions made in June 2006, were... AGENCY Final Test Guideline; Product Performance of Skin-applied Insect Repellents of Insect and Other... Product Performance of Skin-applied Insect Repellents of Insect and Other Arthropods Test...

  10. Effects of a warmer climate on seed germination in the subarctic

    PubMed Central

    Milbau, Ann; Graae, Bente Jessen; Shevtsova, Anna; Nijs, Ivan

    2009-01-01

    Background and Aims In a future warmer subarctic climate, the soil temperatures experienced by dispersed seeds are likely to increase during summer but may decrease during winter due to expected changes in snow depth, duration and quality. Because little is known about the dormancy-breaking and germination requirements of subarctic species, how warming may influence the timing and level of germination in these species was examined. Methods Under controlled conditions, how colder winter and warmer summer soil temperatures influenced germination was tested in 23 subarctic species. The cold stratification and warm incubation temperatures were derived from real soil temperature measurements in subarctic tundra and the temperatures were gradually changed over time to simulate different months of the year. Key Results Moderate summer warming (+2·5 °C) substantially accelerated germination in all but four species but did not affect germination percentages. Optimum germination temperatures (20/10°C) further decreased germination time and increased germination percentages in three species. Colder winter soil temperatures delayed the germination in ten species and decreased the germination percentage in four species, whereas the opposite was found in Silene acaulis. In most species, the combined effect of a reduced snow cover and summer warming resulted in earlier germination and thus a longer first growing season, which improves the chance of seedling survival. In particular the recruitment of (dwarf) shrubs (Vaccinium myrtillus, V. vitis-idaea, Betula nana), trees (Alnus incana, Betula pubescens) and grasses (Calamagrostis lapponica, C. purpurea) is likely to benefit from a warmer subarctic climate. Conclusions Seedling establishment is expected to improve in a future warmer subarctic climate, mainly by considerably earlier germination. The magnitudes of the responses are species-specific, which should be taken into account when modelling population growth and migration

  11. Applying Computerized Adaptive Testing to the Negative Acts Questionnaire-Revised: Rasch Analysis of Workplace Bullying

    PubMed Central

    Ma, Shu-Ching; Li, Yu-Chi; Yui, Mei-Shu

    2014-01-01

    Background Workplace bullying is a prevalent problem in contemporary work places that has adverse effects on both the victims of bullying and organizations. With the rapid development of computer technology in recent years, there is an urgent need to prove whether item response theory–based computerized adaptive testing (CAT) can be applied to measure exposure to workplace bullying. Objective The purpose of this study was to evaluate the relative efficiency and measurement precision of a CAT-based test for hospital nurses compared to traditional nonadaptive testing (NAT). Under the preliminary conditions of a single domain derived from the scale, a CAT module bullying scale model with polytomously scored items is provided as an example for evaluation purposes. Methods A total of 300 nurses were recruited and responded to the 22-item Negative Acts Questionnaire-Revised (NAQ-R). All NAT (or CAT-selected) items were calibrated with the Rasch rating scale model and all respondents were randomly selected for a comparison of the advantages of CAT and NAT in efficiency and precision by paired t tests and the area under the receiver operating characteristic curve (AUROC). Results The NAQ-R is a unidimensional construct that can be applied to measure exposure to workplace bullying through CAT-based administration. Nursing measures derived from both tests (CAT and NAT) were highly correlated (r=.97) and their measurement precisions were not statistically different (P=.49) as expected. CAT required fewer items than NAT (an efficiency gain of 32%), suggesting a reduced burden for respondents. There were significant differences in work tenure between the 2 groups (bullied and nonbullied) at a cutoff point of 6 years at 1 worksite. An AUROC of 0.75 (95% CI 0.68-0.79) with logits greater than –4.2 (or >30 in summation) was defined as being highly likely bullied in a workplace. Conclusions With CAT-based administration of the NAQ-R for nurses, their burden was substantially

  12. Leveraging a high resolution microfluidic assay reveals insights into pathogenic fungal spore germination.

    PubMed

    Barkal, Layla J; Walsh, Naomi M; Botts, Michael R; Beebe, David J; Hull, Christina M

    2016-05-16

    Germination of spores into actively growing cells is a process essential for survival and pathogenesis of many microbes. Molecular mechanisms governing germination, however, are poorly understood in part because few tools exist for evaluating and interrogating the process. Here, we introduce an assay that leverages developments in microfluidic technology and image processing to quantitatively measure germination with unprecedented resolution, assessing both individual cells and the population as a whole. Using spores from Cryptococcus neoformans, a leading cause of fatal fungal disease in humans, we developed a platform to evaluate spores as they undergo morphological changes during differentiation into vegetatively growing yeast. The assay uses pipet-accessible microdevices that can be arrayed for efficient testing of diverse microenvironmental variables, including temperature and nutrients. We discovered that temperature influences germination rate, a carbon source alone is sufficient to induce germination, and the addition of a nitrogen source sustains it. Using this information, we optimized the assay for use with fungal growth inhibitors to pinpoint stages of germination inhibition. Unexpectedly, the clinical antifungal drugs amphotericin B and fluconazole did not significantly alter the process or timing of the transition from spore to yeast, indicating that vegetative growth and germination are distinct processes in C. neoformans. Finally, we used the high temporal resolution of the assay to determine the precise defect in a slow-germination mutant. Combining advances in microfluidics with a robust fungal molecular genetic system allowed us to identify and alter key temporal, morphological, and molecular events that occur during fungal germination. PMID:27026574

  13. Sliding Wear Response of a Bronze Bushing: Influence of Applied Load and Test Environment

    NASA Astrophysics Data System (ADS)

    Prasad, B. K.

    2012-10-01

    This investigation pertains to the examination of the sliding wear behavior of a leaded-tin bronze bushing under the conditions of varying applied loads and test environments against a steel shaft. The test environment was changed by adding 5% of solid lubricants like talc and lead to an oil lubricant separately as well as in combination; the fraction of the two (solid) lubricants within the solid lubricant mixture was varied in the range of 25-75% in the latter case. The wear performance of the bushing was characterized in terms of the wear rate, frictional heating, and friction coefficient. The increasing load led to deterioration in the wear response, while the addition of the solid lubricant particles produced a reverse effect. Further, an appreciable difference in the wear behavior was not observed when the tests were conducted in the oil plus talc and oil plus lead lubricant mixtures. However, the oil containing lead and talc together brought about a significant improvement in the wear response; best results were obtained in the case of the lubricant mixture consisting of lead and talc together in the ratio of 3:1 in the oil. The observed wear behavior of the samples has been discussed in terms of specific characteristics of various microconstituents. The features of the wear surfaces and subsurface regions further substantiated the wear response and enabled us to understand the operating material removal mechanisms.

  14. Testing and Analysis Validation of a Metallic Repair Applied to a PRSEUS Tension Panel

    NASA Technical Reports Server (NTRS)

    Przekop, Adam; Jegley, Dawn C.

    2013-01-01

    A design and analysis of a repair concept applicable to a stiffened composite panel based on the Pultruded Rod Stitched Efficient Unitized Structure was recently completed. The damage scenario considered was a midbay-to-midbay saw-cut with a severed stiffener, flange and skin. Advanced modeling techniques such as mesh-independent definition of compliant fasteners and elastic-plastic material properties for metal parts were utilized in the finite element analysis supporting the design effort. A bolted metallic repair was selected so that it could be easily applied in the operational environment. The present work describes results obtained from a tension panel test conducted to validate both the repair concept and finite element analysis techniques used in the design effort. The test proved that the proposed repair concept is capable of sustaining load levels that are higher than those resulting from the current working stress allowables. This conclusion enables upward revision of the stress allowables that had been kept at an overly-conservative level due to concerns associated with repairability of the panels. Correlation of test data with finite element analysis results is also presented and assessed.

  15. Design, fabrication, and test of a graphite/epoxy metering truss. [as applied to the LST

    NASA Technical Reports Server (NTRS)

    Oken, S.; Skoumal, D. E.

    1975-01-01

    A graphite/epoxy metering truss as applied to the large space telescope was investigated. A full-scale truss was designed, fabricated and tested. Tests included static limit loadings, a modal survey and thermal-vacuum distortion evaluation. The most critical requirement was the demonstration of the dimensional stability provided by the graphite/epoxy truss concept. Crucial to the attainment of this objective was the ability to make very sophisticated thermal growth measurements which was provided by a seven beam laser interferometer. The design of the basic truss elements were tuned to provide the high degree of dimensional stability and stiffness required by the truss. The struts and spider assembly were fabricated with Fiberite's AS/934 and HMS/934 broadgoods. The rings utilized T300 graphite fabricate with the same materials. The predicted performance of the truss was developed using the NASTRAN program. These results showed conformance with the critical stiffness and thermal distortion requirements and correlated well with the test results.

  16. Testing of evaluation methods applied to raw infiltration data measured at very heterogeneous mountain forest soils

    NASA Astrophysics Data System (ADS)

    Jacka, Lukas; Pavlasek, Jirka; Pech, Pavel

    2016-04-01

    In order to obtain infiltration parameters and analytical expressions of the cumulative infiltration and infiltration rate, raw infiltration data are often evaluated using various infiltration equations. Knowledge about the evaluation variability of these equations in the specific case of extremely heterogeneous soils provides important information for many hydrological and engineering applications. This contribution presents an evaluation of measured data using five well-established physically-based equations and empirical equations, and makes a comparison of these procedures. Evaluation procedures were applied to datasets measured on three different sites of hydrologically important mountain podzols. A total of 47 single ring infiltration experiments were evaluated using these procedures. From the quality-of-fit perspective, all of the tested equations characterized most of the raw datasets properly. In a few cases, some of the physically-based equations led to poor fits of the datasets measured on the most heterogeneous site (characterized by the lowest depth of the organic horizon, and more bleached eluvial horizon than on the other tested sites). For the parameters evaluated on this site, the sorptivity estimates and the saturated hydraulic conductivity (Ks) estimates were distinctly different between the tested procedures.

  17. Three-dimensional electrical impedance tomography applied to a metal-walled filtration test platform

    NASA Astrophysics Data System (ADS)

    Davidson, J. L.; Ruffino, L. S.; Stephenson, D. R.; Mann, R.; Grieve, B. D.; York, T. A.

    2004-11-01

    The first true three-dimensional image reconstructions from a metal-walled vessel using electrical impedance tomography (EIT) are presented. Two image reconstruction techniques have been applied via relatively sophisticated FEM modelling of a bespoke laboratory test vessel from which data have been obtained using an EIT instrument designed to intrinsically safe requirements. A generalized Tikhonov regularization method is compared with the linear back-projection (LBP) technique. Subsequent image reconstructions strongly suggest that the LBP method when applied to a metal-walled vessel is highly sensitive to the level of detail within the FEM model. By comparison, the regularized technique is far less sensitive to the complexity of the modelled geometry. Additionally, unlike the LBP method, the regularization technique has been successful in accurately reconstructing multiple inhomogeneities within an aqueous system. A further experiment has shown similar sensitivity in a wetted powder-based system. It is concluded that EIT via a regularized difference imaging approach has significant potential for detecting 3D malformations and non-uniformities in industrial pressure filtration systems.

  18. Carbon nanofibers suppress fungal inhibition of seed germination of maize (Zea mays) and barley (Hordeum vulgare L.) crop

    NASA Astrophysics Data System (ADS)

    Joshi, Anjali; Sharma, Arti; Nayyar, Harsh; Verma, Gaurav; Dharamvir, Keya

    2015-08-01

    Carbon nanofibers (CNFs) are one of allotropes of carbon, consists of graphene layers arrangement in the form of stacked cones or like a cup diameter in nanometer and several millimeters in length. Their extraordinary mechanical, chemical and electronic properties are due to their small size. CNFs have been successfully applied in field of medicine in variety of diagnostic methods. They proven to be an excellent system for drug delivery, tissue regeneration, biosensor etc. This research focuses the applications of CNFs in all fields of Agriculture. In the we treated some fungal disease seed of maize and barley using functionalised CNFs. We find that the tested seeds grow just as well as the healthy seeds whereas the untreated fungal disease seeds, by themselves show very poor germination and seedling growth. This simple experiment shows the extraordinary ability of Carbon nanofibers in carrying effectively inside the germinated seeds.

  19. Carbon nanofibers suppress fungal inhibition of seed germination of maize (Zea mays) and barley (Hordeum vulgare L.) crop

    SciTech Connect

    Joshi, Anjali Sharma, Arti; Nayyar, Harsh; Verma, Gaurav; Dharamvir, Keya

    2015-08-28

    Carbon nanofibers (CNFs) are one of allotropes of carbon, consists of graphene layers arrangement in the form of stacked cones or like a cup diameter in nanometer and several millimeters in length. Their extraordinary mechanical, chemical and electronic properties are due to their small size. CNFs have been successfully applied in field of medicine in variety of diagnostic methods. They proven to be an excellent system for drug delivery, tissue regeneration, biosensor etc. This research focuses the applications of CNFs in all fields of Agriculture. In the we treated some fungal disease seed of maize and barley using functionalised CNFs. We find that the tested seeds grow just as well as the healthy seeds whereas the untreated fungal disease seeds, by themselves show very poor germination and seedling growth. This simple experiment shows the extraordinary ability of Carbon nanofibers in carrying effectively inside the germinated seeds.

  20. 41 CFR 300-80.8 - What must we do to apply for a test program extension?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 4 2012-07-01 2012-07-01 false What must we do to apply for a test program extension? 300-80.8 Section 300-80.8 Public Contracts and Property Management Federal Travel Regulation System GENERAL AGENCY REQUIREMENTS 80-RELOCATION EXPENSES TEST PROGRAMS § 300-80.8 What must we do to apply for a test...

  1. Dispersal and Germination Patterns of Monterey Spineflower at Fort Ord Natural Reserve.

    NASA Astrophysics Data System (ADS)

    Chaudhry, Z.

    2014-12-01

    Some species are rare because they are restricted to certain habitats and/or have small population sizes. Monterey spineflower, a federally listed threatened annual plant, is found in open sandy regions of the California coast, in chaparral vegetation around the Monterey Bay. A model based on previous research suggests that the Monterey spineflower population at Fort Ord Natural Reserve should be rapidly increasing, but it is not. This suggests that the model may be using data that overestimates the percentage of spineflower seeds that successfully germinate. I tested three hypotheses to determine the cause of the difference in population sizes between the predicted model and the field results. First, I predicted that the spineflower seeds are blown by the wind into shrubs such as manzanita, and are unable to germinate due to the lack of a suitable environment. I tested this in two ways. A field experiment showed that seeds are easily blow by wind. Next, I took soil cores and found spineflower seeds within the manzanita shrubs. Secondly, I predicted that the germination rate used by the model (90%) was too high. However, my germination experiments did not support this hypothesis because 91% of new seeds successfully germinated. Lastly, I predicted that the newer seeds are more viable than older seeds and therefore have a higher chance of successfully germinating. After germinating seeds in a controlled environment I observed that the seeds from 2014 had a higher number of successfully germinated seeds compared to the number of successfully germinated seeds from 1995 (91% vs 33%). I conclude that the loss of seeds due to wind decreases germination expectancies and older seeds are less viable than new seeds. Therefore, Monterey spineflower is a rare plant because environmental barriers hinder seeds from dispersing to a suitable habitat and successfully germinating while seeds lose viability as they age.

  2. Campanulaceae: a family with small seeds that require light for germination

    PubMed Central

    Koutsovoulou, Katerina; Daws, Matthew I.; Thanos, Costas A.

    2014-01-01

    Background and Aims The Campanulaceae is a large cosmopolitan family, but is understudied in terms of germination, and seed biology in general. Small seed mass (usually in the range 10–200 µg) is a noteworthy trait of the family, and having small seeds is commonly associated with a light requirement. Thus, the purpose of this study was to investigate the effect of light on germination in 131 taxa of the Campanulaceae family, from all five continents of its distribution. Methods For all taxa, seed germination was tested in light (8 or 12 h photoperiod) and continuous darkness under constant and alternating temperatures. For four taxa, the effect of light on germination was examined over a wide range of temperatures on a thermogradient plate, and the possible substitution of the light requirement by gibberellic acid and nitrate was examined in ten taxa. Key Results For all 131 taxa, seed germination was higher in light than in darkness for every temperature tested. Across species, the light requirement decreased significantly with increasing seed mass. For larger seeded species, germination in the dark reached higher levels under alternating than under constant temperatures. Gibberellic acid promoted germination in darkness whereas nitrates partially substituted for a light requirement only in species showing some dark germination. Conclusions A light requirement for germination, observed in virtually all taxa examined, constitutes a collective characteristic of the family. It is postulated that smaller seeded taxa might germinate only on the soil surface or at shallow depths, while larger seeded species might additionally germinate when buried in the soil if cued to do so by fluctuating temperatures. PMID:24232382

  3. Fast Sterility Assessment by Germinable-Endospore Biodosimetry▿ †

    PubMed Central

    Yung, Pun To; Ponce, Adrian

    2008-01-01

    The increased demand for sterile products has created the need for rapid technologies capable of validating the hygiene of industrial production processes. Bacillus endospores are in standard use as biological indicators for evaluating the effectiveness of sterilization processes. Currently, culture-based methods, requiring more than 2 days before results become available, are employed to verify endospore inactivation. We describe a rapid, microscopy-based endospore viability assay (μEVA) capable of enumerating germinable endospores in less than 15 min. μEVA employs time-gated luminescence microscopy to enumerate single germinable endospores via terbium-dipicolinate (Tb-DPA) luminescence, which is triggered under UV excitation as 108 DPA molecules are released during germination on agarose containing Tb3+ and a germinant (e.g., l-alanine). Inactivation of endospore populations to sterility was monitored with μEVA as a function of thermal and UV dosage. A comparison of culturing results yielded nearly identical decimal reduction values, thus validating μEVA as a rapid biodosimetry method for monitoring sterilization processes. The simple Tb-DPA chemical test for germinability is envisioned to enable fully automated instrumentation for in-line monitoring of hygiene in industrial production processes. PMID:18836020

  4. Experimental clipping of sagebrush inhibits seed germination of neighbours.

    PubMed

    Karban, Richard

    2007-09-01

    Current views of plant communities emphasize the importance of competition for resources and colonization ability in determining seedling establishment and plant distributions. Many desert shrubs are surrounded by bare zones that lack other plants or have different suites of species beneath them compared with the open desert surrounding them. Releases of biochemicals as volatiles from leaves, leachates from litter, or exudates from roots have been proposed as mechanisms for this pattern, but such phytotoxicity has been controversial. I tested the hypothesis that experimental clipping of sagebrush foliage enhances its effect as a germination inhibitor. Germination of native forbs and grasses was reduced in association with clipped, compared with unclipped, sagebrush foliage in lath house and field experiments. Sagebrush seeds were not significantly affected. Air contact was required for this inhibition of germination. Soil contact and leaf litter were not required and added little inhibition of germination. These results suggest a potentially large, indirect, and previously overlooked role for interactions between herbivory and germination that could affect plant community structure. PMID:17663712

  5. Fast sterility assessment by germinable-endospore biodosimetry.

    PubMed

    Yung, Pun To; Ponce, Adrian

    2008-12-01

    The increased demand for sterile products has created the need for rapid technologies capable of validating the hygiene of industrial production processes. Bacillus endospores are in standard use as biological indicators for evaluating the effectiveness of sterilization processes. Currently, culture-based methods, requiring more than 2 days before results become available, are employed to verify endospore inactivation. We describe a rapid, microscopy-based endospore viability assay (microEVA) capable of enumerating germinable endospores in less than 15 min. MicroEVA employs time-gated luminescence microscopy to enumerate single germinable endospores via terbium-dipicolinate (Tb-DPA) luminescence, which is triggered under UV excitation as 10(8) DPA molecules are released during germination on agarose containing Tb(3+) and a germinant (e.g., L-alanine). Inactivation of endospore populations to sterility was monitored with microEVA as a function of thermal and UV dosage. A comparison of culturing results yielded nearly identical decimal reduction values, thus validating microEVA as a rapid biodosimetry method for monitoring sterilization processes. The simple Tb-DPA chemical test for germinability is envisioned to enable fully automated instrumentation for in-line monitoring of hygiene in industrial production processes. PMID:18836020

  6. Steroid hormone runoff from agricultural test plots applied with municipal biosolids

    USGS Publications Warehouse

    Yang, Yun-Ya; Gray, James L.; Furlong, Edward T.; Davis, Jessica G.; ReVollo, Rhiannon C.; Borch, Thomas

    2012-01-01

    The potential presence of steroid hormones in runoff from sites where biosolids have been used as agricultural fertilizers is an environmental concern. A study was conducted to assess the potential for runoff of seventeen different hormones and two sterols, including androgens, estrogens, and progestogens from agricultural test plots. The field containing the test plots had been applied with biosolids for the first time immediately prior to this study. Target compounds were isolated by solid-phase extraction (water samples) and pressurized solvent extraction (solid samples), derivatized, and analyzed by gas chromatography–tandem mass spectrometry. Runoff samples collected prior to biosolids application had low concentrations of two hormones (estrone -1 and androstenedione -1) and cholesterol (22.5 ± 3.8 μg L-1). In contrast, significantly higher concentrations of multiple estrogens (-1), androgens (-1), and progesterone (-1) were observed in runoff samples taken 1, 8, and 35 days after biosolids application. A significant positive correlation was observed between antecedent rainfall amount and hormone mass loads (runoff). Hormones in runoff were primarily present in the dissolved phase (<0.7-μm GF filter), and, to a lesser extent bound to the suspended-particle phase. Overall, these results indicate that rainfall can mobilize hormones from biosolids-amended agricultural fields, directly to surface waters or redistributed to terrestrial sites away from the point of application via runoff. Although concentrations decrease over time, 35 days is insufficient for complete degradation of hormones in soil at this site.

  7. EUCAST recommendations for antimicrobial susceptibility testing applied to the three main Campylobacter species isolated in humans.

    PubMed

    Sifré, Elodie; Salha, Ben Amor; Ducournau, Astrid; Floch, Pauline; Chardon, Hubert; Mégraud, Francis; Lehours, Philippe

    2015-12-01

    Antimicrobial susceptibility testing of Campylobacter isolates is of great importance for treatment options especially in systemic diseases. The European Committee for Antimicrobial Susceptibility Testing (EUCAST) recently proposed epidemiological cut-offs (ECOFFs) for a limited number of antimicrobial compounds and for Campylobacter jejuni and Campylobacter coli only. In the present study, the EUCAST method was used after minor modifications to define antimicrobial susceptibility patterns for, 1997 C. jejuni, 419 C. coli and 100 Campylobacter fetus strains received at the French National Reference Center for Campylobacters and Helicobacters. Our results show that the ECOFFs defined by EUCAST for tetracycline and ciprofloxacin can be used for C. jejuni and C. coli. The same ECOFF can be used for erythromycin for the three species. The C. jejuni and C. coli ECOFFs for ciprofloxacin however cannot be applied to C. fetus. We also provide data to categorise two 2 β-lactams of interest for systemic diseases, ampicillin and amoxicillin+clavulanate, for the three species. PMID:26519770

  8. Impact of seed germination data on genebank management

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed viability data on plant genetic resource accessions in cold storage is critical information that impacts many areas of genebank management. Prior to 2002, little germination testing was conducted at the Plant Genetic Resources Conservation Unit (PGRCU), Griffin, GA. Seed was distributed from th...

  9. Seed flotation and germination of salt marsh plants: The effects of stratification, salinity, and/or inundation regime

    USGS Publications Warehouse

    Elsey-Quirk, T.; Middleton, B.A.; Proffitt, C.E.

    2009-01-01

    We examined the effects of cold stratification and salinity on seed flotation of eight salt marsh species. Four of the eight species were tested for germination success under different stratification, salinity, and flooding conditions. Species were separated into two groups, four species received wet stratification and four dry stratification and fresh seeds of all species were tested for flotation and germination. Fresh seeds of seven out of eight species had flotation times independent of salinity, six of which had average flotation times of at least 50 d. Seeds of Spartina alterniflora and Spartina patens had the shortest flotation times, averaging 24 and 26 d, respectively. Following wet stratification, the flotation time of S. alterniflora seeds in higher salinity water (15 and 36 ppt) was reduced by over 75% and germination declined by more than 90%. Wet stratification reduced the flotation time of Distichlis spicata seeds in fresh water but increased seed germination from 2 to 16% in a fluctuating inundation regime. Fresh seeds of Iva frutescens and S. alternflora were capable of germination and therefore are non-dormant during dispersal. Fresh seeds of I. frutescens had similar germination to dry stratified seeds ranging 25-30%. Salinity reduced seed germination for all species except for S. alterniflora. A fluctuating inundation regime was important for seed germination of the low marsh species and for germination following cold stratification. The conditions that resulted in seeds sinking faster were similar to the conditions that resulted in higher germination for two of four species. ?? 2009 Elsevier B.V.

  10. A high-throughput seed germination assay for root parasitic plants

    PubMed Central

    2013-01-01

    Background Some root-parasitic plants belonging to the Orobanche, Phelipanche or Striga genus represent one of the most destructive and intractable weed problems to agricultural production in both developed and developing countries. Compared with most of the other weeds, parasitic weeds are difficult to control by conventional methods because of their life style. The main difficulties that currently limit the development of successful control methods are the ability of the parasite to produce a tremendous number of tiny seeds that may remain viable in the soil for more than 15 years. Seed germination requires induction by stimulants present in root exudates of host plants. Researches performed on these minute seeds are until now tedious and time-consuming because germination rate is usually evaluated in Petri-dish by counting germinated seeds under a binocular microscope. Results We developed an easy and fast method for germination rate determination based on a standardized 96-well plate test coupled with spectrophotometric reading of tetrazolium salt (MTT) reduction. We adapted the Mosmann’s protocol for cell cultures to germinating seeds and determined the conditions of seed stimulation and germination, MTT staining and formazan salt solubilization required to obtain a linear relationship between absorbance and germination rate. Dose–response analyses were presented as applications of interest for assessing half maximal effective or inhibitory concentrations of germination stimulants (strigolactones) or inhibitors (ABA), respectively, using four parameter logistic curves. Conclusion The developed MTT system is simple and accurate. It yields reproducible results for germination bioassays of parasitic plant seeds. This method is adapted to high-throughput screenings of allelochemicals (stimulants, inhibitors) or biological extracts on parasitic plant seed germination, and strengthens the investigations of distinctive features of parasitic plant germination

  11. Phosphorus recycling potential assessment by a biological test applied to wastewater sludge.

    PubMed

    Braak, Etienne; Auby, Sarah; Piveteau, Simon; Guilayn, Felipe; Daumer, Marie-Line

    2016-01-01

    Phosphorus (P) recycling as mineral fertilizer from wastewater activated sludge (WAS) depends on the amount that can be dissolved and separated from the organic matter before the final crystallization step. The aim of the biological phosphorus dissolution potential (BPDP) test developed here was to assess the maximum amount of P that could be biologically released from WAS prior that the liquid phase enters the recovery process. It was first developed for sludge combining enhanced biological phosphorus removal and iron chloride. Because carbohydrates are known to induce acidification during the first stage of anaerobic digestion, sucrose was used as a co-substrate. Best results were obtained after 24-48 h, without inoculum, with a sugar/sludge ratio of 0.5 gCOD/gVS and under strict anaerobic conditions. Up to 75% of the total phosphorus in sludge from a wastewater treatment plant combining enhanced biological phosphorus removal and iron chloride phosphorus removal could be dissolved. Finally, the test was applied to assess BPDP from different sludge using alum compounds for P removal. No dissolution was observed when alum polychloride was used and less than 20% when alum sulphate was used. In all the cases, comparison to chemical acidification showed that the biological process was a major contributor to P dissolution. The possibility to crystallize struvite was discussed from the composition of the liquids obtained. The BPDP will be used not only to assess the potential for phosphorus recycling from sludge, but also to study the influence of the co-substrates available for anaerobic digestion of sludge. PMID:26786893

  12. Numerical tests for effects of various parameters in niching genetic algorithm applied to regional waveform inversion

    NASA Astrophysics Data System (ADS)

    Li, Cong; Lei, Jianshe

    2014-10-01

    In this paper, we focus on the influences of various parameters in the niching genetic algorithm inversion procedure on the results, such as various objective functions, the number of the models in each subpopulation, and the critical separation radius. The frequency-waveform integration (F-K) method is applied to synthesize three-component waveform data with noise in various epicentral distances and azimuths. Our results show that if we use a zero-th-lag cross-correlation function, then we will obtain the model with a faster convergence and a higher precision than other objective functions. The number of models in each subpopulation has a great influence on the rate of convergence and computation time, suggesting that it should be obtained through tests in practical problems. The critical separation radius should be determined carefully because it directly affects the multi-extreme values in the inversion. We also compare the inverted results from full-band waveform data and surface-wave frequency-band (0.02-0.1 Hz) data, and find that the latter is relatively poorer but still has a higher precision, suggesting that surface-wave frequency-band data can also be used to invert for the crustal structure.

  13. Numerical tests for effects of various parameters in niching genetic algorithm applied to regional waveform inversion

    NASA Astrophysics Data System (ADS)

    Li, Cong; Lei, Jianshe

    2014-09-01

    In this paper, we focus on the influences of various parameters in the niching genetic algorithm inversion procedure on the results, such as various objective functions, the number of the models in each subpopulation, and the critical separation radius. The frequency-waveform integration (F-K) method is applied to synthesize three-component waveform data with noise in various epicentral distances and azimuths. Our results show that if we use a zero-th-lag cross-correlation function, then we will obtain the model with a faster convergence and a higher precision than other objective functions. The number of models in each subpopulation has a great influence on the rate of convergence and computation time, suggesting that it should be obtained through tests in practical problems. The critical separation radius should be determined carefully because it directly affects the multi-extreme values in the inversion. We also compare the inverted results from full-band waveform data and surface-wave frequency-band (0.02-0.1 Hz) data, and find that the latter is relatively poorer but still has a higher precision, suggesting that surface-wave frequency-band data can also be used to invert for the crustal structure.

  14. Competency Test Items for Applied Principles of Agribusiness and Natural Resources Occupations. Forestry Component. A Report of Research.

    ERIC Educational Resources Information Center

    Cheek, Jimmy G.; McGhee, Max B.

    An activity was undertaken to develop written criterion-referenced tests for the forestry component of Applied Principles of Agribusiness and Natural Resources. Intended for tenth grade students who have completed Fundamentals of Agribusiness and Natural Resources Occupations, applied principles were designed to consist of three components, with…

  15. Germination Shifts of C3 and C4 Species under Simulated Global Warming Scenario

    PubMed Central

    Zhang, Hongxiang; Yu, Qiang; Huang, Yingxin; Zheng, Wei; Tian, Yu; Song, Yantao; Li, Guangdi; Zhou, Daowei

    2014-01-01

    Research efforts around the world have been increasingly devoted to investigating changes in C3 and C4 species' abundance or distribution with global warming, as they provide important insight into carbon fluxes and linked biogeochemical cycles. However, changes in the early life stage (e.g. germination) of C3 and C4 species in response to global warming, particularly with respect to asymmetric warming, have received less attention. We investigated germination percentage and rate of C3 and C4 species under asymmetric (+3/+6°C at day/night) and symmetric warming (+5/+5°C at day/night), simulated by alternating temperatures. A thermal time model was used to calculate germination base temperature and thermal time constant. Two additional alternating temperature regimes were used to test temperature metrics effect. The germination percentage and rate increased continuously for C4 species, but increased and then decreased with temperature for C3 species under both symmetric and asymmetric warming. Compared to asymmetric warming, symmetric warming significantly overestimated the speed of germination percentage change with temperature for C4 species. Among the temperature metrics (minimum, maximum, diurnal temperature range and average temperature), maximum temperature was most correlated with germination of C4 species. Our results indicate that global warming may favour germination of C4 species, at least for the C4 species studied in this work. The divergent effects of asymmetric and symmetric warming on plant germination also deserve more attention in future studies. PMID:25137138

  16. Essential oils from Mediterranean lamiaceae as weed germination inhibitors.

    PubMed

    Angelini, Luciana G; Carpanese, Giovanna; Cioni, Pier Luigi; Morelli, Ivano; Macchia, Mario; Flamini, Guido

    2003-10-01

    The essential oils obtained from rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and savory (Satureja montana L.) and the four monoterpenes that are their major constituents have been analyzed by GC and GC-MS and tested for their allelopathic properties on the seeds of three different annual weeds (Chenopodium album, Portulaca oleracea, and Echinochloa crus-galli) and three crops (Raphanus sativus, Capsicum annuum, and Lactuca sativa), with the aim to evaluate in vitro their potential as germination inhibitors. The essential oil composition varied with the species, thymol being the main constituent (44%) of thyme and carvacrol (57%) that of savory oil. Differences in essential oil composition were observed within two different rosemary ecotypes, type A, with alpha-pinene (37%) and 1,8-cineole (23%), and type B, characterized by a 2-fold content of 1,8-cineole (47%). This latest essential oil inhibited completely the germination of weeds while concurrently displaying little effect on pepper. The other two oils showed less selective action. S. montana essential oil, with 57% carvacrol, is the most active compound, completely inhibiting germination both of crops and weeds. Borneol, one of the main constituents of the oil of rosemary type B, showed an activity comparable to that of the whole oil. Crop and weed seeds treated with 1,8-cineole showed germination values that were not significantly different from controls, even if a slowing of the germination process expressed in terms of a significant increase in mean germination time was observed. Monoterpene compounds also present in the essential oils mainly represented the volatile fraction released from the crops and their residues into the soil. PMID:14518938

  17. Habitat specialization through germination cueing: a comparative study of herbs from forests and open habitats

    PubMed Central

    ten Brink, Dirk-Jan; Hendriksma, Harmen Pieter; Bruun, Hans Henrik

    2013-01-01

    Background and Aims This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently accompanied by specialization in their regeneration niche; and (2) species are thereby adapted to utilize different windows of opportunity in time (season) and space (habitat). Methods Seed germination response to temperature, light and stratification was tested for 17 congeneric pairs, each consisting of one forest species and one open-habitat species. A factorial design was used with temperature levels and diurnal temperature variation (10 °C constant, 15–5 °C fluctuating, 20 °C constant, 25–15 °C fluctuating), and two light levels (light and darkness) and a cold stratification treatment. The congeneric species pair design took phylogenetic dependence into account. Key Results Species from open habitats germinated better at high temperatures, whereas forest species performed equally well at low and high temperatures. Forest species tended to germinate only after a period of cold stratification that could break dormancy, while species from open habitats generally germinated without cold stratification. The empirically derived germination strategies correspond quite well with establishment opportunities for forest and open-habitat plant species in nature. Conclusions Annual changes in temperature and light regime in temperate forest delimit windows of opportunity for germination and establishment. Germination strategies of forest plants are adaptations to utilize such narrow windows in time. Conversely, lack of fit between germination ecology and environment may explain why species of open habitats generally fail to establish in forests. Germination strategy should be considered an important mechanism for habitat specialization in temperate herbs

  18. Analysis of thermal dependence on the germination of braquiarão seeds using the thermal time model.

    PubMed

    Nakao, E A; Cardoso, V J M

    2016-02-01

    This paper analyzed the thermal dependence on the germination of Urochloa brizantha (Stapf) Webster seeds under constant and fluctuating temperatures through the thermal time model. Germination tests were carried out at constant temperatures ranging from 8 °C to 41.5 °C in order to determine the model parameters: base (Tb), optimal (To) and maximum temperature (Tc) for germination; and the thermal time (θT) required for individual seeds to germinate. Braquiarão seeds germinate within a temperature interval from 8 °C to 41.5 °C, with an optimum range for germination estimated at 31.5 ° ≤ T ≤ 34.5 °C. Actual and expected distributions of cumulative germination percentages of U. brizantha seeds put to germinate both under controlled and uncontrolled temperature regimes were compared, and it can be seen that the model described relatively well the germination at isothermal assays; however the model failed to predict germination at a wide range of thermal fluctuations. Possible explanations for the results are discussed. PMID:26909633

  19. Temperature and moisture requirements for conidial germination of an isolate of Beauveria bassiana, pathogenic to Rhodnius prolixus.

    PubMed

    Luz, C; Fargues, J

    1997-01-01

    The effects of temperature, relative humidity and water activity on germination of conidia of an isolate of Beauveria bassiana (Bals.) Vuill. pathogenic to the triatomine vector of Chagas' disease, Rhodnius prolixus Stål., were investigated in vitro. Germination occurred at temperatures between 15 degrees C and 35 degrees C under saturated atmosphere and the optima ranged from 25 degrees C to 30 degrees C. At the extreme temperatures tested (15 degrees C and 35 degrees C) the germination process was delayed, but germination rates reached more than 95%. Germination of B. bassiana conidia was strongly affected by moisture conditions. The availability of water, in both atmospheric and liquid conditions, caused changes in germination times as well as in germination rates. For example, at 25 degrees C + 0.5 degrees C, germination took place within 20 h at 95.5% RH, whereas it needed 72 h of incubation at 90% RH. Germination times increased as the water activity declined from 0.96 a(w) to 0.92 a(w). Below 0.92 a(w), no germination was observed after a 72 h incubation time. PMID:16283112

  20. 10 CFR 26.67 - Random drug and alcohol testing of individuals who have applied for authorization.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 1 2012-01-01 2012-01-01 false Random drug and alcohol testing of individuals who have applied for authorization. 26.67 Section 26.67 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.67 Random drug and alcohol testing of individuals...

  1. 10 CFR 26.67 - Random drug and alcohol testing of individuals who have applied for authorization.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 1 2013-01-01 2013-01-01 false Random drug and alcohol testing of individuals who have applied for authorization. 26.67 Section 26.67 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.67 Random drug and alcohol testing of individuals...

  2. 10 CFR 26.67 - Random drug and alcohol testing of individuals who have applied for authorization.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Random drug and alcohol testing of individuals who have applied for authorization. 26.67 Section 26.67 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.67 Random drug and alcohol testing of individuals...

  3. 10 CFR 26.67 - Random drug and alcohol testing of individuals who have applied for authorization.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Random drug and alcohol testing of individuals who have applied for authorization. 26.67 Section 26.67 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.67 Random drug and alcohol testing of individuals...

  4. 10 CFR 26.67 - Random drug and alcohol testing of individuals who have applied for authorization.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Random drug and alcohol testing of individuals who have applied for authorization. 26.67 Section 26.67 Energy NUCLEAR REGULATORY COMMISSION FITNESS FOR DUTY PROGRAMS Granting and Maintaining Authorization § 26.67 Random drug and alcohol testing of individuals...

  5. 29 CFR 794.108 - Scope of enterprise must be known before exemption tests can be applied.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Scope of enterprise must be known before exemption tests...)(3) of the Act The âenterpriseâ § 794.108 Scope of enterprise must be known before exemption tests can be applied. The scope of the “enterprise” as defined by section 3(r) of the Act must...

  6. 29 CFR 794.108 - Scope of enterprise must be known before exemption tests can be applied.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Scope of enterprise must be known before exemption tests...)(3) of the Act The âenterpriseâ § 794.108 Scope of enterprise must be known before exemption tests can be applied. The scope of the “enterprise” as defined by section 3(r) of the Act must...

  7. 29 CFR 794.108 - Scope of enterprise must be known before exemption tests can be applied.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Scope of enterprise must be known before exemption tests...)(3) of the Act The âenterpriseâ § 794.108 Scope of enterprise must be known before exemption tests can be applied. The scope of the “enterprise” as defined by section 3(r) of the Act must...

  8. 29 CFR 794.108 - Scope of enterprise must be known before exemption tests can be applied.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Scope of enterprise must be known before exemption tests...)(3) of the Act The âenterpriseâ § 794.108 Scope of enterprise must be known before exemption tests can be applied. The scope of the “enterprise” as defined by section 3(r) of the Act must...

  9. 29 CFR 794.108 - Scope of enterprise must be known before exemption tests can be applied.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Scope of enterprise must be known before exemption tests...)(3) of the Act The âenterpriseâ § 794.108 Scope of enterprise must be known before exemption tests can be applied. The scope of the “enterprise” as defined by section 3(r) of the Act must...

  10. Imaging Local Chemical Microstructure of Germinated Wheat with Synchrotron Infrared Microspectroscopy

    SciTech Connect

    Koc,H.; Wetzel, D.

    2008-01-01

    The spatial resolution enabled by in situ Fourier-transform infrared (FT-IR) microspectroscopy as predicted from our earlier report in Spectroscopy (1) is applied to localized chemical analysis in this vital biological process of seed germination. Germination includes several different biochemical and structural processes. Ultimately, the entire seed is consumed in sustaining the new life that results after sprouting and growth (2-4). Alpha amylase production is the standard evidence for detection of sprouted (germinated) wheat at harvest. Moist preharvest conditions can cause devastating losses and render the harvested wheat unfit for flour production. Dormancy of dry seeds following harvest retards sprouting under proper storage.

  11. Research Problems Associated with Limiting the Applied Force in Vibration Tests and Conducting Base-Drive Modal Vibration Tests

    NASA Technical Reports Server (NTRS)

    Scharton, Terry D.

    1995-01-01

    The intent of this paper is to make a case for developing and conducting vibration tests which are both realistic and practical (a question of tailoring versus standards). Tests are essential for finding things overlooked in the analyses. The best test is often the most realistic test which can be conducted within the cost and budget constraints. Some standards are essential, but the author believes more in the individual's ingenuity to solve a specific problem than in the application of standards which reduce problems (and technology) to their lowest common denominator. Force limited vibration tests and base-drive modal tests are two examples of realistic, but practical testing approaches. Since both of these approaches are relatively new, a number of interesting research problems exist, and these are emphasized herein.

  12. Applicability of Aerospace Materials Ground Flammability Test Data to Spacecraft Environments Theory and Applied Technologies

    NASA Technical Reports Server (NTRS)

    Hirsch, David; Williams, Jim; Beeson, Harold

    2009-01-01

    This slide presentation reviews the use of ground test data in reference to flammability to spacecraft environments. It reviews the current approach to spacecraft fire safety, the challenges to fire safety that the Constellation program poses, the current trends in the evaluation of the Constellation materials flammability, and the correlation of test data from ground flammability tests with the spacecraft environment. Included is a proposal for testing and the design of experiments to test the flammability of materials under similar spacecraft conditions.

  13. Germination tests for assessing biochar quality

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the impact of biochar quality on soil productivity is crucial to the agronomic acceptance of biochar amendments. Our objective in this study was to develop a quick and reliable screening procedures to characterize the quality of biochar amendments. Biochars were evaluated by both seed ...

  14. Shear-Sensitive Liquid Crystal Coating Method Applied Through Transparent Test Surfaces

    NASA Technical Reports Server (NTRS)

    Reda, Daniel C.; Wilder, Michael C.

    1999-01-01

    Research conducted at NASA Ames Research Center has shown that the color-change response of a shear-sensitive liquid crystal coating (SSLCC) to aerodynamic shear depends on both the magnitude of the local shear vector and its direction relative to the observer's in-plane line of sight. In conventional applications, the surface of the SSLCC exposed to aerodynamic shear is illuminated with white light from the normal direction and observed from an oblique above-plane view angle of order 30 deg. In this top-light/top-view mode, shear vectors with components directed away from the observer cause the SSLCC to exhibit color-change responses. At any surface point, the maximum color change (measured from the no-shear red or orange color) always occurs when the local vector is aligned with, and directed away from, the observer. The magnitude of the color change at this vector-observer-aligned orientation scales directly with shear stress magnitude. Conversely, any surface point exposed to a shear vector with a component directed toward the observer exhibits a non-color-change response, always characterized by a rusty-red or brown color, independent of both shear magnitude and direction. These unique, highly directional color-change responses of SSLCCs to aerodynamic shear allow for the full-surface visualization and measurement of continuous shear stress vector distributions. The objective of the present research was to investigate application of the SSLCC method through a transparent test surface. In this new back-light/back-view mode, the exposed surface of the SSLCC would be subjected to aerodynamic shear stress while the contact surface between the SSLCC and the solid, transparent wall would be illuminated and viewed in the same geometrical arrangement as applied in conventional applications. It was unknown at the outset whether or not color-change responses would be observable from the contact surface of the SSLCC, and, if seen, how these color-change responses might

  15. Effects of a magnetic field on the germination of plants

    NASA Astrophysics Data System (ADS)

    Hirota, Noriyuki; Nakagawa, Jun; Kitazawa, Koichi

    1999-04-01

    The effects of a nonuniform magnetic field on the germination of plants were studied. When a 10 T magnetic field was applied at the center of a superconducting magnet, a cucumber shoot germinating in a horizontal bore leaned towards the field center. In contrast, the root grew in the direction opposite the shoot. The observed result seemed to have occurred as a result of the magnetic force influencing the geotaxis of the cucumber. This idea was supported qualitatively by analysis results of the experimental data. Knowledge obtained in this study will be helpful for the evaluation of the effect of the magnetic field on living bodies and suggests the possibility of applying magnetic fields in other areas of research.

  16. 40 CFR 1039.235 - What testing requirements apply for certification?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... standards. See § 1039.240, § 1039.245, and 40 CFR part 1065, subpart E, regarding service accumulation... under 40 CFR 1065.10 and later testing shows that such testing does not produce results that are... alternate procedure. (g) Measure CO2 and CH4 with each low-hour certification test using the...

  17. 40 CFR 1039.235 - What testing requirements apply for certification?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... standards. See § 1039.240, § 1039.245, and 40 CFR part 1065, subpart E, regarding service accumulation... under 40 CFR 1065.10 and later testing shows that such testing does not produce results that are... alternate procedure. (g) Measure CO2 and CH4 with each low-hour certification test using the...

  18. A Comparison of Traditional and Non-Traditional Methods of Testing: Applied Educational Research and Evaluation.

    ERIC Educational Resources Information Center

    Box, Wilford Winston; Barrett, Anita G.

    A study involving two groups of students enrolled in two concurrent 16-week terms of a course taught at two Southwest Texas Junior College campuses compared the effects of traditional and non-traditional testing. The traditional approach consisted of typical individual testing, while the non-traditional approach involved group testing (i.e., two…

  19. Prototype of a test bench for applied research on Extracted beams of the nuclotron accelerator complex

    NASA Astrophysics Data System (ADS)

    Baldin, A. A.; Berlev, A. I.; Bradnova, V.; Butenko, A. V.; Fedorov, A. N.; Kudashkin, I. V.

    2016-05-01

    The results of the development and testing of elements of a test bench for investigating the impact of accelerated particle beams on biological objects, electronics, and other targets are presented. The systems for beam monitoring and target positioning were tested on extracted argon beams in the framework of experiments on studying the radiation hardness of electronic components.

  20. Training Teachers and Serving Students: Applying Usability Testing in Writing Programs

    ERIC Educational Resources Information Center

    McGovern, Heather

    2007-01-01

    Teachers often test course materials by using them in class. Usability testing provides an alternative: teachers receive student feedback and revise materials "before" teaching a class. Case studies based on interviews and observations with two teaching assistants who usability tested materials before teaching introductory technical writing…

  1. In vitro germination characteristics of maize pollen to detect biological activity of environmental pollutants.

    PubMed Central

    Pfahler, P L

    1981-01-01

    In vitro pollen germination was examined as a method to determine the mutagenic and physiological effects of environmental pollutants on higher organisms. Results were presented indicating that mutations could be distinguished by their in vitro germination characteristics if sporophytes homozygous for the mutated allele were tested. The addition of agents directly into the in vitro medium was shown to be an effective method to assess their physiological effects. The exposure of pollen grains during the in vitro germination process to ultraviolet radiation in the B range (280-320 nm) was found to produce little or no change in the germination or ruptured percentage but a sharp decrease in pollen tube growth after 1 hr. In vitro pollen germination appears to be a valuable method to examine the mutation types and physiological effects produced by a broad range of environmental pollutants. In fact, since in vitro germination is related to reproduction and gene transmission, the biological activity of these agents on in vitro germination should be tested routinely to determine their possible effects on food production and gene frequency changes in future generations. Images FIGURE 1. FIGURE 3. PMID:7460877

  2. Phytotoxic Activity of Ocimum tenuiflorum Extracts on Germination and Seedling Growth of Different Plant Species

    PubMed Central

    2014-01-01

    Phytotoxic activity of Ocimum tenuiflorum (Lamiaceae) plant extracts was investigated against the germination and seedling growth of cress (Lepidium sativum), lettuce (Lactuca sativa), alfalfa (Medicago sativa), Italian ryegrass (Lolium multiflorum), barnyard grass (Echinochloa crus-galli), and timothy (Phleum pratense) at four different concentrations. The plant extracts at concentrations greater than 30 mg dry weight equivalent extract mL−1 reduced significantly the total germination percent (GP), germination index (GI), germination energy (GE), speed of emergence (SE), seedling vigour index (SVI), and coefficient of the rate of germination (CRG) of all test species except barnyard grass and GP of lettuce. In contrast, time required for 50% germination (T50) and mean germination time (MGT) were increased at the same or higher than this concentration. The increasing trend of T50 and MGT and the decreasing trend of other indices indicated a significant inhibition or delay of germination of the test species by O. tenuiflorum plant extracts and vice versa. In addition, the shoot and root growth of all test species were significantly inhibited by the extracts at concentrations greater than 10 mg dry weight equivalent extract mL−1. The I50 values for shoot and root growth were ranged from 26 to 104 mg dry weight equivalent extract mL−1. Seedling growth was more sensitive to the extracts compared to seed germination. Results of this study suggest that O. tenuiflorum plant extracts have phytotoxic properties and thus contain phytotoxic substances. Isolation and characterization of those substances from this plant may act as a tool for new natural, biodegradable herbicide development to control weeds. PMID:25032234

  3. Increasing the antioxidant activity, total phenolic and flavonoid contents by optimizing the germination conditions of amaranth seeds.

    PubMed

    Perales-Sánchez, Janitzio X K; Reyes-Moreno, Cuauhtémoc; Gómez-Favela, Mario A; Milán-Carrillo, Jorge; Cuevas-Rodríguez, Edith O; Valdez-Ortiz, Angel; Gutiérrez-Dorado, Roberto

    2014-09-01

    The aim of this study was to optimize the germination conditions of amaranth seeds that would maximize the antioxidant activity (AoxA), total phenolic (TPC), and flavonoid (TFC) contents. To optimize the germination bioprocess, response surface methodology was applied over three response variables (AoxA, TPC, TFC). A central composite rotable experimental design with two factors [germination temperature (GT), 20-45 ºC; germination time (Gt), 14-120 h] in five levels was used; 13 treatments were generated. The amaranth seeds were soaked in distilled water (25 °C/6 h) before germination. The sprouts from each treatment were dried (50 °C/8 h), cooled, and ground to obtain germinated amaranth flours (GAF). The best combination of germination bioprocess variables for producing optimized GAF with the highest AoxA [21.56 mmol trolox equivalent (TE)/100 g sample, dw], TPC [247.63 mg gallic acid equivalent (GAE)/100 g sample, dw], and TFC [81.39 mg catechin equivalent (CAE)/100 g sample, dw] was GT = 30 ºC/Gt = 78 h. The germination bioprocess increased AoxA, TPC, and TFC in 300-470, 829, and 213%, respectively. The germination is an effective strategy to increase the TPC and TFC of amaranth seeds for enhancing functionality with improved antioxidant activity. PMID:24958279

  4. Do seed mass and family affect germination and juvenile performance in Knautia arvensis? A study using failure-time methods

    NASA Astrophysics Data System (ADS)

    Vange, Vibekke; Heuch, Ivar; Vandvik, Vigdis

    2004-05-01

    Germination and seedling establishment are vulnerable stages in the plant life cycle. We investigated how seed mass and family (progeny origin) affect germination and juvenile performance in the grassland herb Knautia arvensis. Seeds were produced by cross-pollination by hand. The fate of 15 individually weighed seeds from each of 15 plants was followed during a 3-month growth chamber experiment. Progeny origin affected germination, both through seed mass and as an independent factor. Two groups of progenies could be distinguished by having rapid or delayed germination. The two groups had similar mean seed masses, but a positive relationship between seed mass and germination rate could be established only among the rapidly germinating progenies. These biologically relevant patterns were revealed because timing of germination was taken into account in the analyses, not only frequencies. Time-to-event data were analysed with failure-time methods, which gave more stable estimates for the relation between germination and seed mass than the commonly applied logistic regression. Progeny origin and seed mass exerted less impact on later characters like juvenile survival, juvenile biomass, and rosette number. These characters were not affected by the timing of germination under the competition-free study conditions. The decrease in the effect of progeny origin from the seed and germination to the juvenile stages suggests that parental effects other than those contributing to the offspring genotype strongly influenced the offspring phenotype at the earliest life stages. Further, the division of progeny germination patterns into two fairly distinct groups indicates that there was a genetic basis for the variation in stratification requirements among parental plants. Field studies are needed to elucidate effects of different timing of germination in the seasonal grasslands that K. arvensis inhabits.

  5. Intranasal Osteopontin for Rodent Germinal Matrix Hemorrhage.

    PubMed

    Malaguit, Jay; Casel, Darlene; Dixon, Brandon; Doycheva, Desislava; Tang, Jiping; Zhang, John H; Lekic, Tim

    2016-01-01

    Germinal matrix hemorrhage (GMH) is the most common and devastating neurological problem of premature infants. Current treatment is largely ineffective and GMH has been nonpreventable. Osteopontin (OPN) is an endogenous protein that has been shown to be neuroprotective, however, it has not been tested in GMH. P7 neonatal rats were subjected to stereotactic ganglionic eminence collagenase infusion. Groups were as follows: (1) sham, (2) GMH + vehicle, (3) GMH + intranasal OPN. Seventy-two hours later, the animals were evaluated using righting reflex, blood-brain barrier (BBB) permeability by Evans blue dye leakage, brain water content, and hemoglobin assay. Intranasal OPN improved outcomes after GMH by attenuation of brain swelling, BBB function, re-bleeding, and neurological outcomes. OPN may play an important role in enhancing neuroprotective brain signaling following GMH. These observed effects may offer novel possibilities for therapy in this patient population. PMID:26463952

  6. Identification of embryo proteins associated with seed germination and seedling establishment in germinating rice seeds.

    PubMed

    Liu, Shu-Jun; Xu, Heng-Heng; Wang, Wei-Qing; Li, Ni; Wang, Wei-Ping; Lu, Zhuang; Møller, Ian Max; Song, Song-Quan

    2016-06-01

    Seed germination is a critical phase in the plant life cycle, but the mechanism of seed germination is still poorly understood. In the present study, rice (Oryza sativa L. cv. Peiai 64S) seeds were sampled individually when they reached different germination stages, quiescent, germinated sensu stricto, germinated completely and seedling, and were used to study the changes in the embryo proteome. A total of 88 protein spots showed a significant change in abundance during germination in water, and the results showed an activation of metabolic processes. Cell division, cell wall synthesis, and secondary metabolism were activated at late seed germination and during preparation for subsequent seedling establishment. Cycloheximide (CHX) at 70μM inhibited seedling establishment without an apparent negative effect on seed germination, while CHX at 500μM completely blocked seed germination. We used this observation to identify the potentially important proteins involved in seed germination (coleoptile protrusion) and seedling establishment (coleoptile and radicle protrusion). Twenty-six protein spots, mainly associated with sugar/polysaccharide metabolism and energy production, showed a significant difference in abundance during seed germination. Forty-nine protein spots, mainly involved in cell wall biosynthesis, proteolysis as well as cell defense and rescue, were required for seedling establishment. The results help improve our understanding of the key events (proteins) involved in germination and seedling development. PMID:27085178

  7. In vitro germination characteristics of maize pollen to detect biological activity of environmental pollutants

    SciTech Connect

    Pfahler, P.L.

    1981-01-01

    In vitro pollen germination in maize was evaluated as a method of assessing the mutagenic and physiological effects of environmental pollutants on higher organisms. The extent of mutations was effectively determined by testing sporophytes homozygous for the mutated allele. Physiological effects were effectively determined when chemical agents were added directly into the in vitro medium. Exposure of pollen grains during in vitro germination to ultraviolet radiation in the range 280-320 nm produced little or no change in the germination or rupture percentage but a sharp decrease in pollen tube growth after 1 hr.

  8. 40 CFR 1051.505 - What special provisions apply for testing snowmobiles?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., operate the engine at its warm idle speed as described in 40 CFR 1065.510. (c) For the full-load operating... the established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. (2) For... specified in 40 CFR part 1065, subpart G. (3) Measure emissions by testing the engine on a dynamometer...

  9. Digital Image Correlation Techniques Applied to Large Scale Rocket Engine Testing

    NASA Technical Reports Server (NTRS)

    Gradl, Paul R.

    2016-01-01

    Rocket engine hot-fire ground testing is necessary to understand component performance, reliability and engine system interactions during development. The J-2X upper stage engine completed a series of developmental hot-fire tests that derived performance of the engine and components, validated analytical models and provided the necessary data to identify where design changes, process improvements and technology development were needed. The J-2X development engines were heavily instrumented to provide the data necessary to support these activities which enabled the team to investigate any anomalies experienced during the test program. This paper describes the development of an optical digital image correlation technique to augment the data provided by traditional strain gauges which are prone to debonding at elevated temperatures and limited to localized measurements. The feasibility of this optical measurement system was demonstrated during full scale hot-fire testing of J-2X, during which a digital image correlation system, incorporating a pair of high speed cameras to measure three-dimensional, real-time displacements and strains was installed and operated under the extreme environments present on the test stand. The camera and facility setup, pre-test calibrations, data collection, hot-fire test data collection and post-test analysis and results are presented in this paper.

  10. Digitisation of electron microscope films: six useful tests applied to three film scanners.

    PubMed

    Henderson, R; Cattermole, D; McMullan, G; Scotcher, S; Fordham, M; Amos, W B; Faruqi, A R

    2007-01-01

    A series of simple tests have been used to measure the performance of flat-bed film scanners suitable for digitisation of electron micrographs. Two of the film scanners evaluated are commercially available and one has been constructed in the laboratory paying special attention to the needs of the electron microscopist. The tests may be useful for others. PMID:16872749

  11. 40 CFR 1039.235 - What testing requirements apply for certification?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... standards. See § 1039.240, § 1039.245, and 40 CFR part 1065, subpart E, regarding service accumulation... under 40 CFR 1065.10 and later testing shows that such testing does not produce results that are... specified in 40 CFR part 1065 in the 2011 and 2012 model years, respectively. Also measure N2O with each...

  12. 40 CFR 1051.505 - What special provisions apply for testing snowmobiles?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... specified in 40 CFR part 1065, subpart G. (3) Measure emissions by testing the engine on a dynamometer with..., operate the engine at its warm idle speed as described in 40 CFR 1065.510. (c) For the full-load operating... the established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. (2)...

  13. 40 CFR 1051.505 - What special provisions apply for testing snowmobiles?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. (2) For... specified in 40 CFR part 1065, subpart G. (3) Measure emissions by testing the engine on a dynamometer with..., operate the engine at its warm idle speed as described in 40 CFR 1065.510. (c) For the full-load...

  14. 40 CFR 1051.505 - What special provisions apply for testing snowmobiles?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. (2) For... specified in 40 CFR part 1065, subpart G. (3) Measure emissions by testing the engine on a dynamometer with..., operate the engine at its warm idle speed as described in 40 CFR 1065.510. (c) For the full-load...

  15. 40 CFR 1051.505 - What special provisions apply for testing snowmobiles?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... the established criteria as specified in 40 CFR 1065.514 to confirm that the test is valid. (2) For... specified in 40 CFR part 1065, subpart G. (3) Measure emissions by testing the engine on a dynamometer with..., operate the engine at its warm idle speed as described in 40 CFR 1065.510. (c) For the full-load...

  16. In Vitro Germination and Tissue Culture Parameters for Mutagenesis, Ploidy Manipulation, and Possible Transformation of Hydrangea macrophylla

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have established parameters for efficient in vitro germination of open pollinated seeds from 17 Hydrangea macrophylla and 2 Hydrangea paniculata cultivars. All tested hydrangea seed had a confirmed light requirement for germination to occur, and contrary to some prior reports, we discovered that ...

  17. Comparison of Modal Analysis Methods Applied to a Vibro-Acoustic Test Article

    NASA Technical Reports Server (NTRS)

    Pritchard, Jocelyn; Pappa, Richard; Buehrle, Ralph; Grosveld, Ferdinand

    2001-01-01

    Modal testing of a vibro-acoustic test article referred to as the Aluminum Testbed Cylinder (ATC) has provided frequency response data for the development of validated numerical models of complex structures for interior noise prediction and control. The ATC is an all aluminum, ring and stringer stiffened cylinder, 12 feet in length and 4 feet in diameter. The cylinder was designed to represent typical aircraft construction. Modal tests were conducted for several different configurations of the cylinder assembly under ambient and pressurized conditions. The purpose of this paper is to present results from dynamic testing of different ATC configurations using two modal analysis software methods: Eigensystem Realization Algorithm (ERA) and MTS IDEAS Polyreference method. The paper compares results from the two analysis methods as well as the results from various test configurations. The effects of pressurization on the modal characteristics are discussed.

  18. Memory of Germinant Stimuli in Bacterial Spores

    PubMed Central

    Wang, Shiwei; Faeder, James R.; Setlow, Peter

    2015-01-01

    ABSTRACT Bacterial spores, despite being metabolically dormant, possess the remarkable capacity to detect nutrients and other molecules in their environment through a biochemical sensory apparatus that can trigger spore germination, allowing the return to vegetative growth within minutes of exposure of germinants. We demonstrate here that bacterial spores of multiple species retain memory of transient exposures to germinant stimuli that can result in altered responses to subsequent exposure. The magnitude and decay of these memory effects depend on the pulse duration as well as on the separation time, incubation temperature, and pH values between the pulses. Spores of Bacillus species germinate in response to nutrients that interact with germinant receptors (GRs) in the spore’s inner membrane, with different nutrient types acting on different receptors. In our experiments, B. subtilis spores display memory when the first and second germinant pulses target different receptors, suggesting that some components of spore memory are downstream of GRs. Furthermore, nonnutrient germinants, which do not require GRs, exhibit memory either alone or in combination with nutrient germinants, and memory of nonnutrient stimulation is found to be more persistent than that induced by GR-dependent stimuli. Spores of B. cereus and Clostridium difficile also exhibit germination memory, suggesting that memory may be a general property of bacterial spores. These observations along with experiments involving strains with mutations in various germination proteins suggest a model in which memory is stored primarily in the metastable states of SpoVA proteins, which comprise a channel for release of dipicolinic acid, a major early event in spore germination. PMID:26604257

  19. 76 FR 19952 - Not Applying the Mark of Inspection Pending Certain Test Results

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-11

    ... (69 FR 1892), announcing that the Agency would not apply the mark of inspection to any animal carcass... Safety of Juice and Juice Products'' (63 FR 24258; May 1, 1998). \\4\\ The annual figure of $15 million is... Flexibility Analysis of the Proposed Rules to Ensure the Safety of Juice and Juice Products'' (63 FR...

  20. A Novel Immunochromatographic Test Applied to a Serological Survey of Japanese Encephalitis Virus on Pig Farms in Korea

    PubMed Central

    Cha, Go-Woon; Lee, Eun Ju; Lim, Eun-Joo; Sin, Kang Suk; Park, Woo Won; Jeon, Doo Young; Han, Myung Guk; Lee, Won-Ja; Choi, Woo-Young; Jeong, Young Eui

    2015-01-01

    Among vertebrate species, pigs are a major amplifying host of Japanese encephalitis virus (JEV) and measuring their seroconversion is a reliable indicator of virus activity. Traditionally, the hemagglutination inhibition test has been used for serological testing in pigs; however, it has several limitations and, thus, a more efficient and reliable replacement test is required. In this study, we developed a new immunochromatographic test for detecting antibodies to JEV in pig serum within 15 min. Specifically, the domain III region of the JEV envelope protein was successfully expressed in soluble form and used for developing the immunochromatographic test. The test was then applied to the surveillance of Japanese encephalitis (JE) in Korea. We found that our immunochromatographic test had good sensitivity (84.8%) and specificity (97.7%) when compared with an immunofluorescence assay used as a reference test. During the surveillance of JE in Korea in 2012, the new immunochromatographic test was used to test the sera of 1,926 slaughtered pigs from eight provinces, and 228 pigs (11.8%) were found to be JEV-positive. Based on these results, we also produced an activity map of JEV, which marked the locations of pig farms in Korea that tested positive for the virus. Thus, the immunochromatographic test reported here provides a convenient and effective tool for real-time monitoring of JEV activity in pigs. PMID:25992769

  1. Quality assurance of the Applied Knowledge Test (AKT) of the MRCGP examination - an immediate post-test questionnaire evaluation of the candidates' views.

    PubMed

    Dixon, Hilton; Blow, Carol; Milne, Paul; Siriwardena, Niroshan; Milne, Heather; Elfes, Christopher

    2015-07-01

    The Applied Knowledge Test (AKT) of the Membership of the Royal College of General Practitioners (MRCGP) examination is a computer-based assessment delivered three times a year. A computerised questionnaire, administered immediately after the test, sought candidates' views as part of the test evaluation. Of 1681 candidates taking the test 1418 (84%) responded. Most candidates believed that the test assessed their knowledge of problems relevant to general practice. Their feedback highlighted areas where improvements could be made. Candidates' views of postgraduate specialty medical examinations in the UK are rarely sought or published. We are not aware of other published evidence. The use of computer-based testing enables immediate candidate feedback and can be used routinely to evaluate the test validity and formats. The views of candidates are an important component of quality assurance in reviewing the content, format and educational experience of a high-stakes examination. PMID:26253057

  2. Infrared Thermography as Applied to Thermal Testing of Power Systems Circuit Boards.

    NASA Astrophysics Data System (ADS)

    Miles, Jonathan James

    All operational electronic equipment dissipates some amount of energy in the form of infrared radiation. Faulty electronic components on a printed circuit board can be categorized as hard (functional) or soft (latent functional). Hard faults are those which are detected during a conventional manufacturing electronic test process. Soft failures, in contrast, are those which are undetectable through conventional testing, but which manifest themselves after a product has been placed into service. Such field defective modules ultimately result in operational failure and subsequently enter a manufacturer's costly repair process. While thermal imaging systems are being used increasingly in the electronic equipment industry as a product-testing tool, applications have primarily been limited to product design or repair processes, with minimal use in a volume manufacturing environment. Use of thermal imaging systems in such an environment has mostly been limited to low-volume products or random screening of high-volume products. Thermal measurements taken in a manufacturing environment are often taken manually, thus defeating their capability of rapid data acquisition and constraining their full potential in a high-volume manufacturing process. Integration of a thermal measurement system with automated testing equipment is essential for optimal use of expensive infrared measurement tools in a high-volume manufacturing environment. However, such a marriage presents problems with respect to both existing manufacturing test processes and infrared measurement techniques. Methods are presented in this dissertation to test automatically for latent faults, those which elude detection during conventional electronic testing, on printed circuit boards. These methods are intended for implementation in a volume manufacturing environment and involve the application of infrared imaging tools. Successful incorporation of infrared testing into existing test processes requires that: PASS

  3. Post-burning regeneration of the Chaco seasonally dry forest: germination response of dominant species to experimental heat shock.

    PubMed

    Jaureguiberry, Pedro; Díaz, Sandra

    2015-03-01

    Plant species of the Chaco seasonally dry forest of central Argentina have presumably been under a low evolutionary pressure to develop specialized fire-response traits, such as heat-stimulated germination. Nevertheless, other historical factors such as seasonal drought and/or endozoochorus dispersal could have led some species to develop heat-tolerant seeds. Therefore, heat-tolerant germination should be more common than heat-stimulated or heat-sensitive germination. To test this, we exposed seeds of 26 dominant species from the Chaco region to a broad range of experimental heat treatments and incubated them for 30 days at 25 °C and 12 h photoperiod. We then scored the percent germination and classified them as heat-stimulated, heat-tolerant or heat-sensitive based on their germination following heat treatments relative to control. Seventeen species showed heat-tolerant germination, including all native graminoids. Seven species showed heat-stimulated germination, under the less-intense heat treatments. Only two species showed heat-sensitive germination. Endozoochory had no influence on germination responses. We suggest that, unlike Mediterranean-climate ecosystems, fire was not a major evolutionary force in the development of Chaco forests, and our results provide greater understanding of the potential response of Chaco plant communities in the face of increasingly frequent fires. PMID:25421096

  4. Priming and temperature limits for germination of dispersal units of Urochloa brizantha (Stapf) Webster cv. basilisk.

    PubMed

    Nakao, E A; Cardoso, V J M

    2015-01-01

    The objective of this study was to evaluate the effect of priming treatments on the upper and lower thermal limits for germination of Urochloa brizantha cv. basilisk, and testing the hypothesis that pré-imbibition affect thermal parameters of the germination. Pre-imbibed seeds both in distilled water (0 MPa) and PEG 6000 solution (-0.5 MPa) were put to germinate in different temperatures. It is suggested that U. brizantha seeds have low response to priming when they were placed to germinate in medium where water is not limiting. The response of U. brizantha seeds to priming is dependent on the temperature and water potential conditions at which the seeds are pre-imbibed, as well as on the germination temperature. The optimum temperature for germination of U. brizantha shift toward warmer temperatures in primed seeds. Priming effect was more pronounced at temperatures closer to the upper and lower limit for germination, but probably that response cannot be accounted for changes in the thermal time constant (θT(g)) and ceiling temperature (Tc(g)). Otherwise, a decrease in the base temperature (Tb) was observed in primed seeds, suggesting that the Tb distribution in U. brizantha seeds is influenced by priming. PMID:25945643

  5. 40 CFR 1048.510 - What transient duty cycles apply for laboratory testing?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... cycle statistics and compare with the established criteria as specified in 40 CFR 1065.514 to confirm... starting the next test. (3) You are not required to measure emissions while the engine is warming...

  6. Weibull analysis applied to the pull adhesion test and fracture of a metal-ceramic interface

    SciTech Connect

    Erck, R.A.; Nichols, F.A.; Schult, D.L.

    1992-11-01

    Various adhesion tests have been developed to measure the mechanical bonding of thin coatings deposited on substrates. In the pull test, pins that have been bonded to the coating under test are pulled with increasing force normal to the coating until the coating is pulled from the substrate. For many systems, large scatter in the data is often observed due to uncontrolled defects in the interface and the brittle nature of the pull test. In this study, the applicability of Weibull statistics to the analysis of adhesion of Ag films to vacuum sputter-cleaned zirconia was examined. Data were obtained for smooth and rough substrates for various levels of adhesion. A good fit of the data to the Weibull distribution was observed. The Weibull modulus was found to depend on the roughness of the substrate, but was insensitive to the adhesion strength.

  7. The Relationship of Deep and Surface Study Approaches on Factual and Applied Test-Bank Multiple-Choice Question Performance

    ERIC Educational Resources Information Center

    Yonker, Julie E.

    2011-01-01

    With the advent of online test banks and large introductory classes, instructors have often turned to textbook publisher-generated multiple-choice question (MCQ) exams in their courses. Multiple-choice questions are often divided into categories of factual or applied, thereby implicating levels of cognitive processing. This investigation examined…

  8. Predicting the Future: Opportunities and Challenges for the Chemical Industry to Apply 21st-Century Toxicity Testing

    PubMed Central

    Settivari, Raja S; Ball, Nicholas; Murphy, Lynea; Rasoulpour, Reza; Boverhof, Darrell R; Carney, Edward W

    2015-01-01

    Interest in applying 21st-century toxicity testing tools for safety assessment of industrial chemicals is growing. Whereas conventional toxicology uses mainly animal-based, descriptive methods, a paradigm shift is emerging in which computational approaches, systems biology, high-throughput in vitro toxicity assays, and high-throughput exposure assessments are beginning to be applied to mechanism-based risk assessments in a time- and resource-efficient fashion. Here we describe recent advances in predictive safety assessment, with a focus on their strategic application to meet the changing demands of the chemical industry and its stakeholders. The opportunities to apply these new approaches is extensive and include screening of new chemicals, informing the design of safer and more sustainable chemical alternatives, filling information gaps on data-poor chemicals already in commerce, strengthening read-across methodology for categories of chemicals sharing similar modes of action, and optimizing the design of reduced-risk product formulations. Finally, we discuss how these predictive approaches dovetail with in vivo integrated testing strategies within repeated-dose regulatory toxicity studies, which are in line with 3Rs principles to refine, reduce, and replace animal testing. Strategic application of these tools is the foundation for informed and efficient safety assessment testing strategies that can be applied at all stages of the product-development process. PMID:25836969

  9. 40 CFR 80.583 - What alternative sampling and testing requirements apply to importers who transport motor vehicle...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false What alternative sampling and testing requirements apply to importers who transport motor vehicle diesel fuel, NRLM diesel fuel, or ECA marine fuel by truck or rail car? 80.583 Section 80.583 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...

  10. 40 CFR 1045.401 - What testing requirements apply to my engines that have gone into service?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false What testing requirements apply to my engines that have gone into service? 1045.401 Section 1045.401 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION...

  11. 40 CFR 1045.401 - What testing requirements apply to my engines that have gone into service?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false What testing requirements apply to my engines that have gone into service? 1045.401 Section 1045.401 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM SPARK-IGNITION...

  12. Predicting the future: opportunities and challenges for the chemical industry to apply 21st-century toxicity testing.

    PubMed

    Settivari, Raja S; Ball, Nicholas; Murphy, Lynea; Rasoulpour, Reza; Boverhof, Darrell R; Carney, Edward W

    2015-03-01

    Interest in applying 21st-century toxicity testing tools for safety assessment of industrial chemicals is growing. Whereas conventional toxicology uses mainly animal-based, descriptive methods, a paradigm shift is emerging in which computational approaches, systems biology, high-throughput in vitro toxicity assays, and high-throughput exposure assessments are beginning to be applied to mechanism-based risk assessments in a time- and resource-efficient fashion. Here we describe recent advances in predictive safety assessment, with a focus on their strategic application to meet the changing demands of the chemical industry and its stakeholders. The opportunities to apply these new approaches is extensive and include screening of new chemicals, informing the design of safer and more sustainable chemical alternatives, filling information gaps on data-poor chemicals already in commerce, strengthening read-across methodology for categories of chemicals sharing similar modes of action, and optimizing the design of reduced-risk product formulations. Finally, we discuss how these predictive approaches dovetail with in vivo integrated testing strategies within repeated-dose regulatory toxicity studies, which are in line with 3Rs principles to refine, reduce, and replace animal testing. Strategic application of these tools is the foundation for informed and efficient safety assessment testing strategies that can be applied at all stages of the product-development process. PMID:25836969

  13. 40 CFR 80.583 - What alternative sampling and testing requirements apply to importers who transport motor vehicle...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... requirements apply to importers who transport motor vehicle diesel fuel, NRLM diesel fuel, or ECA marine fuel... (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Motor Vehicle Diesel Fuel; Nonroad, Locomotive, and Marine Diesel Fuel; and ECA Marine Fuel Sampling and Testing § 80.583...

  14. Effect of phytohormones on seed germination and seedling growth of Coriandrum sativum L.

    PubMed

    Kumar, Mahender; Agnihotri, R K; Vamil, R; Sharma, R

    2014-04-01

    Coriander commonly known as Dhania or Chinese parsley is generally grown for its use in soups, salads, dressing vegetables, seasoning and chutney. Effect of two phytohormones viz. GA3 and 2,4-D on seed germination, seedling growth and various physiological and biochemical parameters were studied. The hormones were applied individually in different concentrations (10, 50 and 100 μM concentrations). Both the hormones enhanced the germination percentage, seedling growth (root and shoot length), leaf area, chlorophyll and carotenoid content. The application of these hormones also decreased the germination time. Maximum germination, shoot length, leaf area and carotenoid content was observed in 100 μm concentration of GA3. Root length, chl. a and chl. b was maximum in 50 μM of 2,4-D and 100 μm GA3, respectively. The application of two hormones exhibited a marked increase on all the parameters studied as compared to the control. PMID:25911855

  15. Photocontrol of the Germination of Onoclea Spores

    PubMed Central

    Towill, Leslie R.; Ikuma, Hiroshi

    1973-01-01

    Light stimulates the germination of spores of the fern Onoclea sensibilis L. At high dosages, broad band red, far red, and blue light promote maximal germination. Maximal sensitivity to these spectral regions is attained from 6 to 48 hours of dark presoaking, and all induced rapid germination after a lag of 30 to 36 hours. Maximal germination is attained approximately 70 hours after irradiation. Dose response curves suggest log linearity. The action spectrum to cause 50% germination shows that spores are most sensitive to irradiation in the red region (620-680 nm) with an incident energy less than 1000 ergs cm−2; sensitivity decreases towards both shorter and longer wavelengths. Although the action spectrum is suggestive of phytochrome involvement, photoreversibility of germination between red and far red light has not been demonstrated with Onoclea spores. An absorption spectrum of the intact spores reveals the presence of chlorophylls and carotenoids. Since the presence of 3-(3,4-dichlorophenyl)-1,1-dimethylurea does not inhibit germination, it is concluded that photosynthesis does not play a role in the germination process. PMID:16658448

  16. 7 CFR 201.20 - Germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... germination for each kind or kind and variety or kind and type of kind and hybrid of agricultural seed present... 7 Agriculture 3 2012-01-01 2012-01-01 false Germination. 201.20 Section 201.20 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  17. 7 CFR 201.20 - Germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... germination for each kind or kind and variety or kind and type of kind and hybrid of agricultural seed present... 7 Agriculture 3 2013-01-01 2013-01-01 false Germination. 201.20 Section 201.20 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  18. 7 CFR 201.20 - Germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... germination for each kind or kind and variety or kind and type of kind and hybrid of agricultural seed present... 7 Agriculture 3 2014-01-01 2014-01-01 false Germination. 201.20 Section 201.20 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  19. 7 CFR 201.20 - Germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... germination each kind, or kind and variety, or kind and type, or kind and hybrid of agricultural seed present... 7 Agriculture 3 2011-01-01 2011-01-01 false Germination. 201.20 Section 201.20 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  20. 7 CFR 201.20 - Germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... germination each kind, or kind and variety, or kind and type, or kind and hybrid of agricultural seed present... 7 Agriculture 3 2010-01-01 2010-01-01 false Germination. 201.20 Section 201.20 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED...

  1. A Study of Germination Inhibition in Fruits.

    ERIC Educational Resources Information Center

    Gill, John

    1982-01-01

    Describes a method for the extraction and bioassay of natural germination inhibitors, requiring only inexpensive equipment and minimal experimental skill. The method has been used to demonstrate qualitative/quantitative differences in germination inhibitor levels in a variety of different fruits or in different tissues within a single fruit.…

  2. Germinated wheat: Phytochemical composition and mixing characteristics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Germinated grain recently attracts interest due to its beneficial effect on human health. In this research, whole wheat flour samples obtained after three days and five days of germination were analyzed for biochemical components, mixing quality, and effects on human breast cancer cells. Germinati...

  3. Neuroprotective effects of Nigella sativa extracts during germination on central nervous system

    PubMed Central

    Islam, Mohammad Hayatul; Ahmad, Iffat Zareen; Salman, Mohammad Tariq

    2015-01-01

    Background: Nigella sativa Linn. which has many acclaimed medicinal properties is an indigenous herbaceous plant and belongs to the Ranunculaceae family, which grows in countries bordering the Mediterranean Sea, Pakistan and India. Objective: This study was designed to investigate the effects of N. sativa seed extracts of different germination phases on the central nervous system (CNS) responses in experimental animals. Materials and Methods: Anxiolytic, locomotor activity of extracts (1 g/kg of body weight) was evaluated in both stressed and unstressed animal models and antiepileptic effect was evaluated by maximal electroshock seizure model keeping diazepam (20 mg/kg) as a positive control. Antidepressant effect was evaluated by forced swim test and tail suspension test keeping imipramine (15 mg/kg) as a positive control. Results: All tested extracts of N. sativa during different phases of germination (especially 5th day germination phase) showed significant (P < 0.001) anxiolytic effect in comparison to control. Diazepam reduced locomotor activity in control (unstressed) rats but did not show affect in stressed rats while N. sativa extracts from germination phases significantly (P < 0.001) reduced locomotor activity in unstressed as well as stressed animals. All the extracts of N. sativa from different germination phases exhibited significant (P < 0.001) reduction in various phases of epileptic seizure on comparison with the reference standard (diazepam). During antidepressant test, N. sativa extracts exhibited a slight reduction in the immobility of rats. Conclusion: During germination, especially in 5th day germination extract, N. sativa showed significant CNS depressant activity as compared to whole seeds that possibly may be due higher content of secondary metabolites produced during germination. PMID:26109765

  4. Interrelationship of Nondestructive Evaluation Methodologies Applied to Testing of Composite Overwrapped Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Leifeste, Mark R.

    2007-01-01

    Composite Overwrapped Pressure Vessels (COPVs) are commonly used in spacecraft for containment of pressurized gases and fluids, incorporating strength and weight savings. The energy stored is capable of extensive spacecraft damage and personal injury in the event of sudden failure. These apparently simple structures, composed of a metallic media impermeable liner and fiber/resin composite overwrap are really complex structures with numerous material and structural phenomena interacting during pressurized use which requires multiple, interrelated monitoring methodologies to monitor and understand subtle changes critical to safe use. Testing of COPVs at NASA Johnson Space Center White Sands T est Facility (WSTF) has employed multiple in-situ, real-time nondestructive evaluation (NDE) methodologies as well as pre- and post-test comparative techniques to monitor changes in material and structural parameters during advanced pressurized testing. The use of NDE methodologies and their relationship to monitoring changes is discussed based on testing of real-world spacecraft COPVs. Lessons learned are used to present recommendations for use in testing, as well as a discussion of potential applications to vessel health monitoring in future applications.

  5. Applying Adverse Outcome Pathways (AOPs) to support Integrated Approaches to Testing and Assessment (IATA).

    PubMed

    Tollefsen, Knut Erik; Scholz, Stefan; Cronin, Mark T; Edwards, Stephen W; de Knecht, Joop; Crofton, Kevin; Garcia-Reyero, Natalia; Hartung, Thomas; Worth, Andrew; Patlewicz, Grace

    2014-12-01

    Chemical regulation is challenged by the large number of chemicals requiring assessment for potential human health and environmental impacts. Current approaches are too resource intensive in terms of time, money and animal use to evaluate all chemicals under development or already on the market. The need for timely and robust decision making demands that regulatory toxicity testing becomes more cost-effective and efficient. One way to realize this goal is by being more strategic in directing testing resources; focusing on chemicals of highest concern, limiting testing to the most probable hazards, or targeting the most vulnerable species. Hypothesis driven Integrated Approaches to Testing and Assessment (IATA) have been proposed as practical solutions to such strategic testing. In parallel, the development of the Adverse Outcome Pathway (AOP) framework, which provides information on the causal links between a molecular initiating event (MIE), intermediate key events (KEs) and an adverse outcome (AO) of regulatory concern, offers the biological context to facilitate development of IATA for regulatory decision making. This manuscript summarizes discussions at the Workshop entitled "Advancing AOPs for Integrated Toxicology and Regulatory Applications" with particular focus on the role AOPs play in informing the development of IATA for different regulatory purposes. PMID:25261300

  6. Small RNA mediated regulation of seed germination

    PubMed Central

    Das, Shabari Sarkar; Karmakar, Prakash; Nandi, Asis Kumar; Sanan-Mishra, Neeti

    2015-01-01

    Mature seeds of most of the higher plants harbor dormant embryos and go through the complex process of germination under favorable environmental conditions. The germination process involves dynamic physiological, cellular and metabolic events that are controlled by the interplay of several gene products and different phytohormones. The small non-coding RNAs comprise key regulatory modules in the process of seed dormancy and germination. Recent studies have implicated the small RNAs in plant growth in correlation with various plant physiological processes including hormone signaling and stress response. In this review we provide a brief overview of the regulation of seed germination or dormancy while emphasizing on the current understanding of the role of small RNAs in this regard. We have also highlighted specific examples of stress responsive small RNAs in seed germination and discussed their future potential. PMID:26528301

  7. Testing the Pareto against the lognormal distributions with the uniformly most powerful unbiased test applied to the distribution of cities.

    PubMed

    Malevergne, Yannick; Pisarenko, Vladilen; Sornette, Didier

    2011-03-01

    Fat-tail distributions of sizes abound in natural, physical, economic, and social systems. The lognormal and the power laws have historically competed for recognition with sometimes closely related generating processes and hard-to-distinguish tail properties. This state-of-affair is illustrated with the debate between Eeckhout [Amer. Econ. Rev. 94, 1429 (2004)] and Levy [Amer. Econ. Rev. 99, 1672 (2009)] on the validity of Zipf's law for US city sizes. By using a uniformly most powerful unbiased (UMPU) test between the lognormal and the power-laws, we show that conclusive results can be achieved to end this debate. We advocate the UMPU test as a systematic tool to address similar controversies in the literature of many disciplines involving power laws, scaling, "fat" or "heavy" tails. In order to demonstrate that our procedure works for data sets other than the US city size distribution, we also briefly present the results obtained for the power-law tail of the distribution of personal identity (ID) losses, which constitute one of the major emergent risks at the interface between cyberspace and reality. PMID:21517562

  8. Testing the Pareto against the lognormal distributions with the uniformly most powerful unbiased test applied to the distribution of cities

    NASA Astrophysics Data System (ADS)

    Malevergne, Yannick; Pisarenko, Vladilen; Sornette, Didier

    2011-03-01

    Fat-tail distributions of sizes abound in natural, physical, economic, and social systems. The lognormal and the power laws have historically competed for recognition with sometimes closely related generating processes and hard-to-distinguish tail properties. This state-of-affair is illustrated with the debate between Eeckhout [Amer. Econ. Rev.SCIEAS0002-828210.1257/0002828043052303 94, 1429 (2004)] and Levy [Amer. Econ. Rev.SCIEAS0002-828210.1257/aer.99.4.1672 99, 1672 (2009)] on the validity of Zipf’s law for US city sizes. By using a uniformly most powerful unbiased (UMPU) test between the lognormal and the power-laws, we show that conclusive results can be achieved to end this debate. We advocate the UMPU test as a systematic tool to address similar controversies in the literature of many disciplines involving power laws, scaling, “fat” or “heavy” tails. In order to demonstrate that our procedure works for data sets other than the US city size distribution, we also briefly present the results obtained for the power-law tail of the distribution of personal identity (ID) losses, which constitute one of the major emergent risks at the interface between cyberspace and reality.

  9. Innovative vibration technique applied to polyurethane foam as a viable substitute for conventional fatigue testing

    NASA Astrophysics Data System (ADS)

    Peralta, Alexander; Just-Agosto, Frederick; Shafiq, Basir; Serrano, David

    2012-12-01

    Lifetime prediction using three-point bending (TPB) can at times be prohibitively time consuming and costly, whereas vibration testing at higher frequency may potentially save time and revenue. A vibration technique that obtains lifetimes that reasonably match those determined under flexural TPB fatigue is developed. The technique designs the specimen with a procedure based on shape optimization and finite element analysis. When the specimen is vibrated in resonance, a stress pattern that mimics the stress pattern observed under conventional TPB fatigue testing is obtained. The proposed approach was verified with polyurethane foam specimens, resulting in an average error of 4.5% when compared with TPB.

  10. Genotyping of Endosperms to Determine Seed Dormancy Genes Regulating Germination Through Embryonic, Endospermic, or Maternal Tissues in Rice

    PubMed Central

    Gu, Xing-You; Zhang, Jinfeng; Ye, Heng; Zhang, Lihua; Feng, Jiuhuan

    2014-01-01

    Seed dormancy is imposed by one or more of the embryo, endosperm, and maternal tissues that belong to two generations and represent two ploidy levels. Many quantitative trait loci (QTL) have been identified for seed dormancy as measured by gross effects on reduced germination rate or delayed germination in crop or model plants. This research developed an endosperm genotype−based genetic approach to determine specific tissues through which a mapped QTL regulates germination using rice as a model. This approach involves testing germination velocity for partially after-ripened seeds harvested from single plants heterozygous for a tested QTL and genotyping endosperms from individual germinated and nongerminated seeds with a codominant DNA marker located on the QTL peak region. Information collected about the QTL includes genotypic frequencies in germinated and/or nongerminated subpopulations; allelic frequency distributions during a germination period; endosperm or embryo genotypic differences in germination velocity; and genotypic frequencies for gametes involved in the double fertilization to form the sampled seeds. Using this approach, the seed dormancy loci SD12, SD1-2, and SD7-1 were determined to regulate germination through the embryo, endosperm, and maternal tissues, respectively; SD12 and SD1-2 acted additively on germination velocity in the offspring tissues; and SD12 also was associated with the preferential fertilization of male gametes in rice. This new genetic approach can be used to characterize mapped genes/QTL for tissue-specific functions in endospermic seeds and for marker-assisted selection of QTL alleles before or immediately after germination in crop breeding. PMID:25480961

  11. 77 FR 73401 - Not Applying the Mark of Inspection Pending Certain Test Results

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-10

    ...The Food Safety and Inspection Service (FSIS) is announcing that it is changing its procedures and will withhold its determination as to whether meat and poultry products are not adulterated, and thus eligible to enter commerce, until all test results that bear on the determination have been received. This notice responds to the comments FSIS received on the Federal Register notice it issued......

  12. Investigating Content and Face Validity of English Language Placement Test Designed by Colleges of Applied Sciences

    ERIC Educational Resources Information Center

    Al-Adawi, Sharifa S. A.; Al-Balushi, Aaisha A. K.

    2016-01-01

    An English placement test (PT) is an essential component of any foundation program. It helps place students into their suitable language proficiency level so that they do not spend time learning materials below or above their levels. It also helps teachers to prepare teaching materials to students of similar levels (Brown, 2004; Illinois, 2012).…

  13. Developing and Testing an Online Tool for Teaching GIS Concepts Applied to Spatial Decision-Making

    ERIC Educational Resources Information Center

    Carver, Steve; Evans, Andy; Kingston, Richard

    2004-01-01

    The development and testing of a Web-based GIS e-learning resource is described. This focuses on the application of GIS for siting a nuclear waste disposal facility and the associated principles of spatial decision-making using Boolean and weighted overlay methods. Initial student experiences in using the system are analysed as part of a research…

  14. Genetic Algorithm Based Multi-Agent System Applied to Test Generation

    ERIC Educational Resources Information Center

    Meng, Anbo; Ye, Luqing; Roy, Daniel; Padilla, Pierre

    2007-01-01

    Automatic test generating system in distributed computing context is one of the most important links in on-line evaluation system. Although the issue has been argued long since, there is not a perfect solution to it so far. This paper proposed an innovative approach to successfully addressing such issue by the seamless integration of genetic…

  15. In vitro chemical and cellular tests applied to uranium trioxide with different hydration states.

    PubMed Central

    Ansoborlo, E; Chalabreysse, J; Hengé-Napoli, M H; Pujol, E

    1992-01-01

    A simple and rapid in vitro chemical solubility test applicable to industrial uranium trioxide (UO3) was developed together with two in vitro cellular tests using rat alveolar macrophages maintained either in gas phase or in alginate beads at 37 degrees C. Industrial UO3 was characterized by particle size, X-ray, and IR spectra, and chemical transformation (e.g., aging and hydration of the dust) was also studied. Solvents used for the in vitro chemical solubility study included carbonates, citrates, phosphates, water, Eagle's basal medium, and Gamble's solution (simulated lung fluid), alone, with oxygen, or with superoxide ions. Results, expressed in terms of the half-time of dissolution, according to International Commission on Radiological Protection (ICRP) classification (D,W,Y), varied for different hydration states of UO3, showing a lower solubility of hydrated UO3 in solvents compared to basic UO3 or UO3 heated at 450 degrees C. Two in vitro cellular tests on cultured rat alveolar macrophages (cells maintained in gas phase and cells immobilized in alginate beads) were used on the same UO3 samples and generally showed a lower solution transfer rate in the presence of macrophages than in the culture medium alone. The results of in vitro chemical and cellular tests were compared, with four main conclusions: a good reproducibility of the three tests in Eagle's basal medium the effect of hydration state on solubility, the classification of UO3 in terms of ICRP solubility criteria, and the ability of macrophages to decrease uranium solubility in medium. PMID:1396449

  16. Fracture toughness of bleached enamel: Effect of applying three different nanobiomaterials by nanoindentation test

    PubMed Central

    Khoroushi, Maryam; Mazaheri, Hamid; Saneie, Tahere; Samimi, Pouran

    2016-01-01

    Background: Despite the absence of dispute about the efficacy of bleaching agents, a prime concern is about their compromising effect on the enamel structure. This in vitro study investigated whether the addition of three different biomaterials, including nano-bioactive glass (n-BG)/nano-hydroxy apetite (n-HA)/nano-amorphous calcium phosphate (n-ACP), to bleaching agents can affect the fracture toughness (FT) and vickers hardness number (VHN) of bovine enamel. Materials and Methods: The crowns of the newly extracted permanent bovine incisors teeth were separated from the root and sectioned along their central line; one half serving as the control specimen and the other half as the test specimen. After mounting and polishing procedure, all the control specimens (C) were subjected to nano-indentation test to obtain the baseline values of FT. Then, the control specimens were exposed to a 38% hydrogen peroxide for four times, each time for 10 min. The test specimens were divided into three groups and treated as follows, with the same protocol used for the control specimens: Group 1; ACP + hydrogen peroxide (HP) mixed gel; Group 2 BG + HP mixed gel; and Group 3 HA + HP mixed gel. FT measurements with nano-indentation were carried out subsequent to bleaching experiments. Data were analyzed using SPSS and Kruskal–Wallis test (α = 0.05). Results: A significant difference in young's modulus (YM), VHN, and FT at baseline and subsequent to bleaching in control group was observed. However, no significant differences were found in YM, VHN, and FT between the test groups, compared to the respective baseline values. Conclusion: Under the limitations of the current study, it can be concluded that the n-HA, n-ACP, and n-BG could be potential biomaterials used to reduce the adverse effects of tooth bleaching. PMID:27307669

  17. System Integral Test by BWR Drywell Cooler Applied as Phase-II Accident Management

    SciTech Connect

    Nagasaka, Hideo; Tobimatsu, Toshimi; Tahara, Mika; Yokobori, Seiichi; Akinaga, Makoto

    2002-07-01

    This paper deals with the system interaction performance using the BWR drywell local cooler (DWC) in combination with containment spray as a Japanese Phase-II accident management (AM). By using almost full height simulation test facility (GIRAFFE-DWC) with scaling ratio of 1/600, the system integral tests simulating BWR low pressure vessel failure sequence were accomplished during about 14 hours. In case of DWC application, the containment pressure increase was found milder due to DWC heat removal performance. Initial spray timing was delayed about 3 hours and each spray period was reduced almost by half. It was concluded that the application of a BWR DWC to Phase-II AM measure is quite promising from the point of delaying or preventing the containment venting. (authors)

  18. Remarks on Some Mechanical Small-Scale Tests Applied to Properties of Materials

    NASA Astrophysics Data System (ADS)

    Cardu, Marilena; Seccatore, Jacopo

    2016-06-01

    The paper presents the results of test campaigns on small-scale strength properties (particularly, micro-hardness) performed on two homogeneous materials: calcite, a very common and widespread mineral that is characterized by its relatively low Mohs hardness and its high reactivity with even weak acids; and glass, an amorphous solid characterized by the absence of the long-range order which defines crystalline materials. After a synthetic description of the principles underlying two of the three classical comminution laws, known as Kick's law and Rittinger's law, experimental results are discussed. The results of the tests performed show that both scale effect and size effect contribute to the non-constancy of mechanical properties at small scale for crystalline materials. On the other hand, for amorphous materials, a theoretical law considering size effects gives considerably different results from empirical measurements. Considerations and an extended discussion address these findings.

  19. [Germination of Ficus insipida (Moraceae) seeds from toucan (Ramphastos sulfuratus) and spider monkey (Ateles geoffroyi) feces].

    PubMed

    Domínguez-Domínguez, Laura E; Morales-Mávil, Jorge E; Alba-Landa, Juan

    2006-06-01

    To test the null hypothesis that two vertebrate fructivores, toucans (Ramphastos sulfuratus) and spider monkeys (Ateles geoffroyi), are equally specialized in germinating Ficus insipida seeds after these have passed through their digestive tracts, we fed fruits to captive individuals. We extracted seeds from feces and placed them on filter paper in petri dishes under controled light, temperature and humidity. Control seeds had not passed through a digestive tract. We found that a greater proportion of seeds from A. geofroyi (65%) germinated (R. sulfuratus: 4%). The germinative value was also greater in seeds from monkey feces (rate=13.76; toucan 0.046; control group 0.172). If, despite individual variability of seeds and dispersers, future studies continue to show that A. geoffroyi favors germination more (maybe because of a longer digestion time), this would indicate that diet specialization is not necessarily related to dispersal efficiency. PMID:18494309

  20. Generalized wave-front reconstruction algorithm applied in a Shack-Hartmann test.

    NASA Astrophysics Data System (ADS)

    Weiyao, Zou; Zhang, Zhenchao

    2000-01-01

    A generalized numerical wave-front reconstruction method is proposed that is suitable for diversified irregular pupil shapes of optical systems to be measured. That is, to make a generalized and regular normal equation set, the test domain is extended to a regular square shape. The compatibility of this method is discussed in detail, and efficient algorithms (such as the Cholesky method) for solving this normal equation set are given. In addition, the authors give strict analyses of not only the error propagation in the wave-front estimate but also of the discretization errors of this domain extension algorithm. Finally, some application examples are given to demonstrate this algorithm.

  1. An empirical test of the Theory of Planned Behaviour applied to contraceptive use in rural Uganda.

    PubMed

    Kiene, Susan M; Hopwood, Sarah; Lule, Haruna; Wanyenze, Rhoda K

    2014-12-01

    There is a high unmet need for contraceptives in developing countries such as Uganda, with high population growth, where efforts are needed to promote family planning and contraceptive use. Despite this high need, little research has investigated applications of health-behaviour-change theories to contraceptive use among this population. This study tested the Theory of Planned Behaviour's ability to predict contraceptive-use-related behaviours among post-partum women in rural Uganda. Results gave modest support to the theory's application and suggest an urgent need for improved theory-based interventions to promote contraceptive use in the populations of developing countries. PMID:23928989

  2. An Empirical Test of the Theory of Planned Behaviour Applied to Contraceptive Use in Rural Uganda

    PubMed Central

    Kiene, Susan M.; Hopwood, Sarah; Lule, Haruna; Wanyenze, Rhoda K.

    2013-01-01

    There is a high unmet need for contraceptives in developing countries such as Uganda, with high population growth, where efforts are needed to promote family planning and contraceptive use. Despite this high need, little research has investigated applications of health behaviour change theories to contraceptive use amongst this population. The present study tested the Theory of Planned Behaviour’s ability to predict contraceptive use-related behaviours among postpartum women in rural Uganda. Results gave modest support to the theory’s application and suggest an urgent need for improved theory-based interventions to promote contraceptive use in the populations of developing countries. PMID:23928989

  3. An applied test of the social learning theory of deviance to college alcohol use.

    PubMed

    DeMartino, Cynthia H; Rice, Ronald E; Saltz, Robert

    2015-04-01

    Several hypotheses about influences on college drinking derived from the social learning theory of deviance were tested and confirmed. The effect of ethnicity on alcohol use was completely mediated by differential association and differential reinforcement, whereas the effect of biological sex on alcohol use was partially mediated. Higher net positive reinforcements to costs for alcohol use predicted increased general use, more underage use, and more frequent binge drinking. Two unexpected finding were the negative relationship between negative expectations and negative experiences, and the substantive difference between nondrinkers and general drinkers compared with illegal or binge drinkers. The discussion considers implications for future campaigns based on Akers's deterrence theory. PMID:25630048

  4. Photoinduced Seed Germination of Oenothera biennis L

    PubMed Central

    Ensminger, Peter A.; Ikuma, Hiroshi

    1987-01-01

    The photoinduction period of Oenothera biennis L. seed germination was analyzed by varying the photoinduction temperature and by substituting red light pulses for continuous red light. At 24°C, seeds require 36 hours of continuous red light for maximal percent germination. The optimal photoinduction temperature is 32°C, with higher and lower temperatures being strongly inhibitory. A 30 minute exposure to far-red light, given immediately after a red light period of 1 to 36 hours, reduces germination by about 25%. Seeds escape from far-red inhibition with a half-time of 5 to 10 hours, depending on the length of the red exposure that precedes the far-red light. Periodic 15 minute pulses of red light can substitute for continuous red light in stimulating germination. Ted red light pulses, with 6 hours of darkness between successive pulses, cause maximal germination. The response to periodic red light is fully reversible by far-red light. Probit analysis of the periodic light response shows that as the length of the dark periods between successive pulses increases, less incident light is needed to induce germination but the population variance in light sensitivity remains constant. Probit analysis of the temperature response shows that as the photoinduction temperature increases from 16 to 32°C, less incident light is needed to induce germination and the population variance in light sensitivity also increases. PMID:16665825

  5. Geographic profiling applied to testing models of bumble-bee foraging

    PubMed Central

    Raine, Nigel E.; Rossmo, D. Kim; Le Comber, Steven C.

    2008-01-01

    Geographic profiling (GP) was originally developed as a statistical tool to help police forces prioritize lists of suspects in investigations of serial crimes. GP uses the location of related crime sites to make inferences about where the offender is most likely to live, and has been extremely successful in criminology. Here, we show how GP is applicable to experimental studies of animal foraging, using the bumble-bee Bombus terrestris. GP techniques enable us to simplify complex patterns of spatial data down to a small number of parameters (2–3) for rigorous hypothesis testing. Combining computer model simulations and experimental observation of foraging bumble-bees, we demonstrate that GP can be used to discriminate between foraging patterns resulting from (i) different hypothetical foraging algorithms and (ii) different food item (flower) densities. We also demonstrate that combining experimental and simulated data can be used to elucidate animal foraging strategies: specifically that the foraging patterns of real bumble-bees can be reliably discriminated from three out of nine hypothetical foraging algorithms. We suggest that experimental systems, like foraging bees, could be used to test and refine GP model predictions, and that GP offers a useful technique to analyse spatial animal behaviour data in both the laboratory and field. PMID:18664426

  6. What words and where? Applying usability testing techniques to name a new live reference service

    PubMed Central

    Duncan, Vicky; Fichter, Darlene M.

    2004-01-01

    Objective: A user-focused design approach was taken to develop a new “live reference” service at the Health Sciences Library, University of Saskatchewan. The name of the service, the placement of the links, and the design of a graphical button were seen as key elements in creating service awareness and its subsequent use. Methods: To ensure library users recognized and understood the label for the new service, selected library users were given an opportunity to choose a phrase that would best describe the service. The top two preferred phrases were then placed on the library Web pages as text and graphic images for further testing. Some pages had links in multiple locations to determine which placement worked best. Task-based usability testing was carried out with participants who were unaware of the new service. Participants were observed as they completed seven Website tasks arranged in increasing levels of difficulty to see whether they would notice the live reference service and seek assistance. Results: The high level of recognition and use of the service indicate that the label name and link placement were effective with library Website users. Conclusions: Using user-centered design methodology helped ensure that the new live reference service was visible and used and demonstrated the effectiveness of the user-centered design approach for adding new services to an existing Website. PMID:15098051

  7. Analysis of the absorbed hydrogen in cladding tubes applied in the QUENCH-LOCA tests

    SciTech Connect

    Grosse, M.; Roessger, C.; Stuckert, J.; Steinbrueck, M.; Walter, M.; Klimenkov, M.; Kaestner, A.

    2012-07-01

    A shortened loss of coolant scenario was simulated experimentally at fuel rod bundle scale in the QUENCH-LO test. All pressurized rods burst at temperatures between 790 and 855 deg. C. The hydrogen distribution in the cladding of chosen fuel rod simulators was studied by neutron radiography and tomography. It was shown that the time between burst and quenching as well as the temperatures occurring during this period, and hence the degree of inner oxidation, are important parameters for the hydrogen uptake. No hydrogen uptake was measured for the specimen with 63 s or less between burst and quenching. For longer time intervals, hydrogen enriched bands were formed. These bended bands are oriented non-symmetrically to the tube axis. Micro-structure investigations give hints that the hydrogen keeps in solution in the a-zirconium lattice. The hydrogen enriched bands influence the mechanical properties of the rods, characterized by a higher hardness. Brittle fracture occurs in these bands in the tensile test. (authors)

  8. Blade Displacement Measurement Technique Applied to a Full-Scale Rotor Test

    NASA Technical Reports Server (NTRS)

    Abrego, Anita I.; Olson, Lawrence E.; Romander, Ethan A.; Barrows, Danny A.; Burner, Alpheus W.

    2012-01-01

    Blade displacement measurements using multi-camera photogrammetry were acquired during the full-scale wind tunnel test of the UH-60A Airloads rotor, conducted in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel. The objectives were to measure the blade displacement and deformation of the four rotor blades as they rotated through the entire rotor azimuth. These measurements are expected to provide a unique dataset to aid in the development and validation of rotorcraft prediction techniques. They are used to resolve the blade shape and position, including pitch, flap, lag and elastic deformation. Photogrammetric data encompass advance ratios from 0.15 to slowed rotor simulations of 1.0, thrust coefficient to rotor solidity ratios from 0.01 to 0.13, and rotor shaft angles from -10.0 to 8.0 degrees. An overview of the blade displacement measurement methodology and system development, descriptions of image processing, uncertainty considerations, preliminary results covering static and moderate advance ratio test conditions and future considerations are presented. Comparisons of experimental and computational results for a moderate advance ratio forward flight condition show good trend agreements, but also indicate significant mean discrepancies in lag and elastic twist. Blade displacement pitch measurements agree well with both the wind tunnel commanded and measured values.

  9. Field test of infrared thermography applied to biogas controlling in landfill sites

    NASA Astrophysics Data System (ADS)

    Madruga, Francisco J.; Muñoz, Jaime M.; González, Daniel A.; Tejero, Juan I.; Cobo, Adolfo; Gil, José L.; Conde, Olga M.; López-Higuera, Jose M.

    2007-04-01

    The gases accumulated inside the landfill as result of the fermentation of Municipal Solid Waste (MSW) known as biogas, are taking into consideration all possible uses as direct transformation into electricity. The system for collecting, regulating and controlling the biogas must include all the necessary safety features where the biogas leakage presents a high impact. Infrared thermography can be use to detect gas leakages due to the differences in temperature between the gas and the immediate surroundings. This method is able to monitor a wide area of landfill sites, quickly. This technology will not be effective if the differences in temperature are not better than five degrees. This paper describes a field test conducted to study the limitations of the infrared thermography caused by weather conditions and the moment of day or/and season when the thermal images was captured. Pipelines, borders, cells, covers, slopes and leakage (hot spots) are studied and optimum conditions are defined.

  10. A Theoretical Investigation of Composite Overwrapped Pressure Vessel (COPV) Mechanics Applied to NASA Full Scale Tests

    NASA Technical Reports Server (NTRS)

    Greene, N.; Thesken, J. C.; Murthy, P. L. N.; Phoenix, S. L.; Palko, J.; Eldridge, J.; Sutter, J.; Saulsberry, R.; Beeson, H.

    2006-01-01

    A theoretical investigation of the factors controlling the stress rupture life of the National Aeronautics and Space Agency's (NASA) composite overwrapped pressure vessels (COPVs) continues. Kevlar(TradeMark) fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar(TradeMark) filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However, due to the presence of a load sharing liner, the manufacturing induced residual stresses and the complex mechanical response, the state of actual fiber stress in flight hardware and test articles is not clearly known. This paper is a companion to the experimental investigation reported in [1] and develops a theoretical framework necessary to design full-scale pathfinder experiments and accurately interpret the experimentally observed deformation and failure mechanisms leading up to static burst in COPVs. The fundamental mechanical response of COPVs is described using linear elasticity and thin shell theory and discussed in comparison to existing experimental observations. These comparisons reveal discrepancies between physical data and the current analytical results and suggest that the vessel's residual stress state and the spatial stress distribution as a function of pressure may be completely different from predictions based upon existing linear elastic analyses. The 3D elasticity of transversely isotropic spherical shells demonstrates that an overly compliant transverse stiffness relative to membrane stiffness can account for some of this by shifting a thin shell problem well into the realm of thick shell response. The use of calibration procedures are demonstrated as calibrated thin shell model results and finite element results are shown to be in good agreement with the experimental results. The successes reported here have lead to continuing work with full scale testing of larger NASA COPV

  11. A Theoretical Investigation of Composite Overwrapped Pressure Vessel (COPV) Mechanics Applied to NASA Full Scale Tests

    NASA Technical Reports Server (NTRS)

    Thesken, John C.; Murthy, Pappu L. N.; Phoenix, S. L.; Greene, N.; Palko, Joseph L.; Eldridge, Jeffrey; Sutter, James; Saulsberry, R.; Beeson, H.

    2009-01-01

    A theoretical investigation of the factors controlling the stress rupture life of the National Aeronautics and Space Administration's (NASA) composite overwrapped pressure vessels (COPVs) continues. Kevlar (DuPont) fiber overwrapped tanks are of particular concern due to their long usage and the poorly understood stress rupture process in Kevlar filaments. Existing long term data show that the rupture process is a function of stress, temperature and time. However due to the presence of a load sharing liner, the manufacturing induced residual stresses and the complex mechanical response, the state of actual fiber stress in flight hardware and test articles is not clearly known. This paper is a companion to a previously reported experimental investigation and develops a theoretical framework necessary to design full-scale pathfinder experiments and accurately interpret the experimentally observed deformation and failure mechanisms leading up to static burst in COPVs. The fundamental mechanical response of COPVs is described using linear elasticity and thin shell theory and discussed in comparison to existing experimental observations. These comparisons reveal discrepancies between physical data and the current analytical results and suggest that the vessel s residual stress state and the spatial stress distribution as a function of pressure may be completely different from predictions based upon existing linear elastic analyses. The 3D elasticity of transversely isotropic spherical shells demonstrates that an overly compliant transverse stiffness relative to membrane stiffness can account for some of this by shifting a thin shell problem well into the realm of thick shell response. The use of calibration procedures are demonstrated as calibrated thin shell model results and finite element results are shown to be in good agreement with the experimental results. The successes reported here have lead to continuing work with full scale testing of larger NASA COPV

  12. Effect of high pressure on green pea seeds germination and plantlets development

    NASA Astrophysics Data System (ADS)

    Alexandre, Elisabete M. C.; Carvalho, Andreia M.; Saraiva, Jorge A.

    2014-01-01

    The aim of this work was to study the impact of high pressure (50 MPa, 10 min) on germination of pea seeds with different imbibition times (0, 12 and 36 h). The parameters analysed were the percentage of germinated seeds, length of roots and stems, number of leaves developed and the weight of young plantlets. Peroxidase (POD), polyphenol oxidase (PPO), pectin methylesterase (PME) and total proteolytic activity were analysed in seeds after the pressure treatment and in leaves after the germination period. Results showed that 50 MPa applied during 10 min retarded the germination onset and inhibited seeds to germinate. The pressure treatment increased and decreased the length of roots and stems, respectively. The number of leaves per germinated seed decreased with the pressure treatment. Enzymatic activities of seeds showed that only total proteolytic activity was significantly reduced by pressure and only for 0 h of imbibition. POD and PPO activities determined in leaves of the plantlets increased with the pressure treatment, while PME activity also increased but only for 12 h of imbibition and total proteolytic activity decreased.

  13. Germination under Extreme Hypobaric and Hypoxic Environment

    NASA Astrophysics Data System (ADS)

    Hashimoto, Hirofumi

    Is the agriculture on Mars without a pressured greenhouse dome possible? In order to inves-tigate a possibility of plant cultivation for the space agriculture on Mars, germination rate for six species of plant, Jute, Chrysanthemum, Komatsuna, Cucumber, Okra, and Eggplant under extreme hypobaric and hypoxic condition was measured. Oxygen partial pressure was 1kPa which was equal to 1/100 of normal earth atmosphere. Seeds of Jute and Cucumber were able to germinate in six species. In the case of Jute, germination rate under the oxygen partial pressure of 1kPa was very high, 70

  14. Advancing the vesosome, a multifunctional drug delivery platform, toward applied in vivo testing

    NASA Astrophysics Data System (ADS)

    Wong, Benjamin J.

    An optimal drug delivery vehicle should circulate long enough to reach the site of illness or disease, possess a large drug loading capacity, retain its contents over the course of treatment, and be able deliver its contents at a rate appropriate for maximum therapeutic benefit at the site of interest. The vesosome, a large lipid bilayer enclosing multiple, smaller liposomes, is our solution to addressing these needs. The external lipid bilayer offers a second barrier of protection for interior components and can also serve as the anchor for active targeting components. Furthermore, internal compartmentalization permits customization of separate environments for multiple therapeutics and release triggers. Previous work established the ability of the vesosome to retain its contents in vitro an order of magnitude longer than liposomes. To be viable in vivo, the vesosome must be functionalized for biocompatibility and tracking, and its synthetic procedure must be repeatable, reliable and result in a purified product. The vesosome was functionalized by introducing biocompatible polymers, such as poly(ethylene glycol) (PEG), and fluorescent dyes in their lipid-bound forms into the external membrane of the vesosome. The external vesosomal membrane is formed from large, flat lipid sheets in the interdigitated (L betaI) phase which, when heated, are used to encapsulate smaller drug-containing vesicles. Through X-Ray diffraction (XRD) and freeze-fracture transmission electron microscopy (FF-TEM), we established that the molar amounts of functionalized lipid required to label the vesosome for tracking and biocompatibility (˜5--7mol% total) did not prevent the formation of the interdigitated phase. Thus, functionalization of the external vesosome membrane can be achieved through functionalization of interdigitated sheets. For in vivo testing, functionalized vesosomes must be separated from unencapsulated vesicles and purification was performed using size exclusion

  15. Essays in applied microeconomics: measuring the multilateral allocation of rent and dual tests of market power

    SciTech Connect

    Kerkvliet, J.

    1986-01-01

    The first essay develops a general econometric procedure for the join estimation of rents in a bilateral monopoly/oligopoly market for an intermediate good. This procedure is utilized to measure the rent-gathering success of firms involved in the extraction, transportation, and consumption of Wyoming coal. Statistical results indicate that railroads and coal producers capture 23% of potential rent, while taxing authorities and utilities capture 7 and 47%, respectively. Further statistical tests indicate that rents have shifted towards railroads since their deregulation in 1980 and that railroads and coal producers engage in price discrimination. The second essay estimates the extent to which regulated electric utilities are inefficient in the use of base-load fossil fuels. Utilities are assumed to be shadow profit maximizers acting as if they face shadow prices which may diverge from observed prices because of monopoly power in output markets, monopsony power in input markets, or distortions induced by fuel-adjustment-clause rate making. Supply, demand, and actual profit equations are derived from a behavioral profit function, and the model is estimated for a sample of utilities using Wyoming and Montana coal. Results indicate that this group of utilities uses fuel inefficiently.

  16. Testing the cleaning effectiveness of new ecological aqueous dispersions applied on old icons

    NASA Astrophysics Data System (ADS)

    Vasilache, Viorica; Sandu, Irina Crina Anca; Pruteanu, Silvea; Caldeira, Ana Teresa; Simionescu, Atena Elena; Sandu, Ion

    2016-03-01

    Adherent deposits are very aggressive towards ancient heritage paintings since they affect the varnish and the painting's layers, sometimes reaching the preparative layers. The biggest problem to the restorer is their removal without affecting the patina, the transparent varnish (well preserved) and fine colour glazes made during painting. Therefore, their removal requires preliminary cleaning tests that allow the optimization of the cleaning system composition that is going to be used. The study was focused on organic natural systems, as colourless supernatants, some of them used during ages, but insufficiently studied. The paper presents an evaluation of the effectiveness of cleaning varnished icons of the nineteenth century, with complex conservation cases using supernatants derived from aqueous dispersions extracted from vegetables and dry indigenous herbal infusions. Best results, after six consecutive cleaning steps, on tempera old icon was obtained for a mixture made of mature white onion juice + extract of Soapwort flowers + corn silk tea + acacia tea. As a best result after just one cleaning step was obtained for a quaternary mixture composed from mature white onion juice + mature carrot juice + corn silk tea + aqueous extract of Soapwort flowers.

  17. Expansion of Perturbation Theory Applied to Shim Rotation Automation of the Advanced Test Reactor

    NASA Astrophysics Data System (ADS)

    Peterson, Joshua Loren

    In 2007, the Department of Energy (DOE) declared the Advanced Test Reactor (ATR) a National Scientific User Facility (NSUF). This declaration expanded the focus of the ATR to include diversified classes of academic and industrial experiments. An essential part of the new suite of more accurate and flexible codes being deployed to support the NSUF is their ability to predict reactor behavior at startup, particularly the position of the outer shim control cylinders (OSCC). The current method used for calculating the OSCC positions during a cycle startup utilizes a heuristic trial and error approach that is impractical with the computationally intensive reactor physics tools, such as NEWT. It is therefore desirable that shim rotation prediction for startup be automated. Shim rotation prediction with perturbation theory was chosen to be investigated as one method for use with startup calculation automation. A modified form of first order perturbation theory, called phase space interpolated perturbation theory, was developed to more accurately model shim rotation prediction. Shim rotation prediction is just one application for this new modified form of perturbation theory. Phase space interpolated perturbation theory can be used on any application where the range of change to the system is known a priori, but the magnitude of change is not known. A cubic regression method was also developed to automate shim rotation prediction by using only forward solutions to the transport equation.

  18. Energy Smart Schools--Applied Research, Field Testing, and Technology Integration

    SciTech Connect

    Nebiat Solomon; Robin Vieira; William L. Manz; Abby Vogen; Claudia Orlando; Kimberlie A. Schryer

    2004-12-01

    The National Association of State Energy Officials (NASEO) in conjunction with the California Energy Commission, the Energy Center of Wisconsin, the Florida Solar Energy Center, the New York State Energy Research and Development Authority, and the Ohio Department of Development's Office of Energy Efficiency conducted a four-year, cost-share project with the U.S. Department of Energy (USDOE), Office of Energy Efficiency and Renewable Energy to focus on energy efficiency and high-performance technologies in our nation's schools. NASEO was the program lead for the MOU-State Schools Working group, established in conjunction with the USDOE Memorandum of Understanding process for collaboration among state and federal energy research and demonstration offices and organizations. The MOU-State Schools Working Group included State Energy Offices and other state energy research organizations from all regions of the country. Through surveys and analyses, the Working Group determined the school-related energy priorities of the states and established a set of tasks to be accomplished, including the installation and evaluation of microturbines, advanced daylighting research, testing of schools and classrooms, and integrated school building technologies. The Energy Smart Schools project resulted in the adoption of advanced energy efficiency technologies in both the renovation of existing schools and building of new ones; the education of school administrators, architects, engineers, and manufacturers nationwide about the energy-saving, economic, and environmental benefits of energy efficiency technologies; and improved the learning environment for the nation's students through use of better temperature controls, improvements in air quality, and increased daylighting in classrooms. It also provided an opportunity for states to share and replicate successful projects to increase their energy efficiency while at the same time driving down their energy costs.

  19. Effect of marble industry effluent on seed germination, post germinative growth and productivity of Zea mays L.

    PubMed

    Akbar, Fazal; Hadi, Fazal; Ullah, Zakir; Zia, Muhammad Amir

    2007-11-15

    A green house study was conducted at the University of Malakand, NWFP, Pakistan to evaluate the effect of marble industry effluent on soil pH, germination, post germinative growth and productivity of maize. The experiment was conducted in triplicate form for each treatment and tape water was used as control (T0). Effluents were diluted with tap water at concentration of 20% (T1), 40% (T2), 60% (T3), 80% (T4) and also used 100% (T5) concentration in 4 kg soil pot(-1) and plants were grown for 90 days. Results showed that there was a linear increase in pH of soil with increase in effluent concentration while germination, root length and stem girth was enhanced and found maximum at 40% concentration of effluent applied. The shoot length and root dry biomass was depressed as compared to control. It is concluded from the present study that marble industry effluent can be used as a fertilizer in low concentration especially for highly acidic soil but there is still need to carry out series of greenhouse and field trials to ascertain the fertilizer potentials of this effluent for maize crop. PMID:19090297

  20. Applying the theory of planned behaviour to explain HIV testing in antenatal settings in Addis Ababa - a cohort study

    PubMed Central

    2011-01-01

    Background To facilitate access to the prevention of mother-to-child HIV transmission (PMTCT) services, HIV counselling and testing are offered routinely in antenatal care settings. Focusing a cohort of pregnant women attending public and private antenatal care facilities, this study applied an extended version of the Theory of Planned Behaviour (TPB) to explain intended- and actual HIV testing. Methods A sequential exploratory mixed methods study was conducted in Addis Ababa in 2009. The study involved first time antenatal attendees from public- and private health care facilities. Three Focus Group Discussions were conducted to inform the TPB questionnaire. A total of 3033 women completed the baseline TPB interviews, including attitudes, subjective norms, perceived behavioural control and intention with respect to HIV testing, whereas 2928 completed actual HIV testing at follow up. Data were analysed using descriptive statistics, Chi-square tests, Fisher's Exact tests, Internal consistency reliability, Pearson's correlation, Linear regression, Logistic regression and using Epidemiological indices. P-values < 0.05 was considered significant and 95% Confidence Interval (CI) was used for the odds ratio. Results The TPB explained 9.2% and 16.4% of the variance in intention among public- and private health facility attendees. Intention and perceived barriers explained 2.4% and external variables explained 7% of the total variance in HIV testing. Positive and negative predictive values of intention were 96% and 6% respectively. Across both groups, subjective norm explained a substantial amount of variance in intention, followed by attitudes. Women intended to test for HIV if they perceived social support and anticipated positive consequences following test performance. Type of counselling did not modify the link between intended and actual HIV testing. Conclusion The TPB explained substantial amount of variance in intention to test but was less sufficient in explaining

  1. The Role of Water in Germination.

    ERIC Educational Resources Information Center

    Bicak, Charles J.

    1986-01-01

    Describes a laboratory experiment which focuses on the importance of water in germination and seedling emergence. Discusses the activity's design, expected results, and possible application. Offers suggestions for extending the experiment. (ML)

  2. Seedling survival of Handroanthus impetiginosus (Mart ex DC) Mattos in a semi-arid environment through modified germination speed and post-germination desiccation tolerance.

    PubMed

    Martins, J R; Edvaldo, A A S; Alvarenga, A A; Rodrigues, A C; Ribeiro, D E; Toorop, P E

    2015-11-01

    Uniform rapid seed germination generally forms a great risk for the plant population if subsequent intermittent precipitation causes desiccation and seedling death. Handroanthus impetiginosus can be found commonly in a wide range of biomes within Brazil including those that are semi-arid. Germination and early growth was studied to understand how germinated seeds survive under these stringent conditions. Accessions were sampled from four seasonally dry biomes in Brazil. Precipitation at the start of the rainy season in the Caatinga, a semi-arid biome, is less predictable and the number of successive dry days per dry interval in the first four months of the rainy season was higher than in the other studied biomes. Plants from the Caatinga produced thicker seeds and this trait concurred with slow germination and stronger osmotic inhibition of germination across the accessions, forming a stress avoidance mechanism in the Caatinga. Post-germination desiccation tolerance was high in the Caatinga accession, could be re-induced in accessions from biomes with more regular precipitation (Cerrado and transition zone), but remained poor in the Cerradão accession; thus forming a stress tolerance mechanism. Production of adventitious roots ascertained survival of all tested individuals from all four locations, even if protruded radicles did not survive desiccation, forming an additional stress tolerance mechanism. A sequence of stress avoidance and stress tolerance mechanisms in seeds and germinated seeds was associated with precipitation patterns in different biomes. These mechanisms purportedly allow rapid seedling establishment when conditions are suitable and enable survival of the young seedling when conditions are adverse. PMID:26675900

  3. Genome-Wide Association Study Identifies Loci for Salt Tolerance during Germination in Autotetraploid Alfalfa (Medicargo sativa L.) using Genotyping by Sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    : In this study, we used a diverse panel of alfalfa accessions to identify molecular markers associated with salt tolerance during germination by genome-wide association (GWA) mapping and genotyping-by-sequencing (GBS). Three levels of salt treatments were applied during seed germination. Phenotypic...

  4. Oxygen dependency of germinating Brassica seeds.

    PubMed

    Park, Myoung Ryoul; Hasenstein, Karl H

    2016-02-01

    Establishing plants in space, Moon or Mars requires adaptation to altered conditions, including reduced pressure and composition of atmospheres. To determine the oxygen requirements for seed germination, we imbibed Brassica rapa seeds under varying oxygen concentrations and profiled the transcription patterns of genes related to early metabolism such as starch degradation, glycolysis, and fermentation. We also analyzed the activity of lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH), and measured starch degradation. Partial oxygen pressure (pO2) greater than 10% resulted in normal germination (i.e., protrusion of radicle about 18 hours after imbibition) but lower pO2 delayed and reduced germination. Imbibition in an oxygen-free atmosphere for three days resulted in no germination but subsequent transfer to air initiated germination in 75% of the seeds and the root growth rate was transiently greater than in roots germinated under ambient pO2. In hypoxic seeds soluble sugars degraded faster but the content of starch after 24 h was higher than at ambient oxygen. Transcription of genes related to starch degradation, α-amylase (AMY) and Sucrose Synthase (SUS), was higher under ambient O2 than under hypoxia. Glycolysis and fermentation pathway-related genes, glucose phosphate isomerase (GPI), 6-phosphofructokinase (PFK), fructose 1,6-bisphosphate aldolase (ALD), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate decarboxylase (PDC), LDH, and ADH, were induced by low pO2. The activity of LDH and ADH was the highest in anoxic seeds. Germination under low O2 conditions initiated ethanolic fermentation. Therefore, sufficient oxygen availability is important for germination before photosynthesis provides necessary oxygen and the determination of an oxygen carrying capacity is important for uniform growth in space conditions. PMID:26948011

  5. Oxygen dependency of germinating Brassica seeds

    NASA Astrophysics Data System (ADS)

    Park, Myoung Ryoul; Hasenstein, Karl H.

    2016-02-01

    Establishing plants in space, Moon or Mars requires adaptation to altered conditions, including reduced pressure and composition of atmospheres. To determine the oxygen requirements for seed germination, we imbibed Brassica rapa seeds under varying oxygen concentrations and profiled the transcription patterns of genes related to early metabolism such as starch degradation, glycolysis, and fermentation. We also analyzed the activity of lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH), and measured starch degradation. Partial oxygen pressure (pO2) greater than 10% resulted in normal germination (i.e., protrusion of radicle about 18 hours after imbibition) but lower pO2 delayed and reduced germination. Imbibition in an oxygen-free atmosphere for three days resulted in no germination but subsequent transfer to air initiated germination in 75% of the seeds and the root growth rate was transiently greater than in roots germinated under ambient pO2. In hypoxic seeds soluble sugars degraded faster but the content of starch after 24 h was higher than at ambient oxygen. Transcription of genes related to starch degradation, α-amylase (AMY) and Sucrose Synthase (SUS), was higher under ambient O2 than under hypoxia. Glycolysis and fermentation pathway-related genes, glucose phosphate isomerase (GPI), 6-phosphofructokinase (PFK), fructose 1,6-bisphosphate aldolase (ALD), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), pyruvate decarboxylase (PDC), LDH, and ADH, were induced by low pO2. The activity of LDH and ADH was the highest in anoxic seeds. Germination under low O2 conditions initiated ethanolic fermentation. Therefore, sufficient oxygen availability is important for germination before photosynthesis provides necessary oxygen and the determination of an oxygen carrying capacity is important for uniform growth in space conditions.

  6. Rapid and high seed germination and large soil seed bank of Senecio aquaticus in managed grassland.

    PubMed

    Suter, Matthias; Lüscher, Andreas

    2012-01-01

    Senecio aquaticus, regionally a Red List species in Europe, has become increasingly abundant in agricultural grassland of medium to high management intensity in Switzerland, Southern Germany, and Austria in recent years, where it is a threat for animal and human health due to its toxicity. In this study, we investigated the seed ecology of S. aquaticus to help protection of the species in relic populations while improving its control when abundant in managed grassland. Germination percentages of fresh ripe seeds of S. aquaticus were on average 68% in 2008, but only 45% in 2010, indicating yearly variation. Germination was generally fast: ten days after the onset of the tests, often more than 45% of all seeds had germinated. When covered with a soil layer of 5 mm, germination was only 16% compared to 63% in full light. Seeds buried in the soil for one and two years showed a germination of 78%, significantly higher than that of fresh ripe seeds, thus suggesting a stimulating effect of cold-wet stratification on germination and long seed survival in the soil. In grasslands with established populations of S. aquaticus, the number of germinable seeds of the species ranged from 361 to 1875 m⁻² in topsoil (0-10 cm) with an average of 1139 m⁻². The large seed bank and the rapid and high germination of S. aquaticus suggest that allowing seed formation is important for its preservation in relic populations. With respect to agricultural grassland, strategies to control the species should initially target hindering seed production and dispersal. PMID:22272180

  7. Rapid and High Seed Germination and Large Soil Seed Bank of Senecio aquaticus in Managed Grassland

    PubMed Central

    Suter, Matthias; Lüscher, Andreas

    2012-01-01

    Senecio aquaticus, regionally a Red List species in Europe, has become increasingly abundant in agricultural grassland of medium to high management intensity in Switzerland, Southern Germany, and Austria in recent years, where it is a threat for animal and human health due to its toxicity. In this study, we investigated the seed ecology of S. aquaticus to help protection of the species in relic populations while improving its control when abundant in managed grassland. Germination percentages of fresh ripe seeds of S. aquaticus were on average 68% in 2008, but only 45% in 2010, indicating yearly variation. Germination was generally fast: ten days after the onset of the tests, often more than 45% of all seeds had germinated. When covered with a soil layer of 5 mm, germination was only 16% compared to 63% in full light. Seeds buried in the soil for one and two years showed a germination of 78%, significantly higher than that of fresh ripe seeds, thus suggesting a stimulating effect of cold-wet stratification on germination and long seed survival in the soil. In grasslands with established populations of S. aquaticus, the number of germinable seeds of the species ranged from 361 to 1875 m−2 in topsoil (0–10 cm) with an average of 1139 m−2. The large seed bank and the rapid and high germination of S. aquaticus suggest that allowing seed formation is important for its preservation in relic populations. With respect to agricultural grassland, strategies to control the species should initially target hindering seed production and dispersal. PMID:22272180

  8. Does thermal time for germination vary among populations of a tree legume (Peltophorum dubium)?

    PubMed

    Andrade, L F D; Cardoso, V J M

    2016-04-19

    Few works report the use of degree-days (DD) - used in crops to predict events and schedule management activities - to describe the germination of tropical trees. The cardinal temperatures (base, optimum and ceiling temperature) for germination of the species may vary depending on the seed provenance. Peltophorum dubium (Spreng.) Taub. is an early successional leguminous tree widely distributed in South America, often occurring as cultivated or naturalized trees, thus considered to be a good example for testing DD model in tree species. The main objective of this study was to describe the seed germination response of different populations of P. dubium as function of DD accumulation during germination assays in semi-controlled (fluctuating temperatures) conditions. Germination assays with manually scarified seeds sown in aluminum sheet trays filled with a composed substrate were performed under greenhouse conditions at different times. Three methods were employed in order to describe the accumulation of thermal time throughout the assays and, considering the seed lot and sowing time, a trapezoid area method was relatively more effective in describing the germination. The germination curves of P. dubium seeds from different populations, expressed in degree-days estimated directly from temperature records schedules, tend to be more clustered suggesting little variation among thermal time requirements in different seed provenances. Otherwise, the thermal time requirement can vary depending on the time of sowing, and any increase in DD requirement when the assays were performed under higher mean temperatures can be related to a thermal effect on the germination of scarified seeds. PMID:27097080

  9. Using hyperspectral imaging to determine germination of native Australian plant seeds.

    PubMed

    Nansen, Christian; Zhao, Genpin; Dakin, Nicole; Zhao, Chunhui; Turner, Shane R

    2015-04-01

    We investigated the ability to accurately and non-destructively determine the germination of three native Australian tree species, Acacia cowleana Tate (Fabaceae), Banksia prionotes L.F. (Proteaceae), and Corymbia calophylla (Lindl.) K.D. Hill & L.A.S. Johnson (Myrtaceae) based on hyperspectral imaging data. While similar studies have been conducted on agricultural and horticultural seeds, we are unaware of any published studies involving reflectance-based assessments of the germination of tree seeds. Hyperspectral imaging data (110 narrow spectral bands from 423.6nm to 878.9nm) were acquired of individual seeds after 0, 1, 2, 5, 10, 20, 30, and 50days of standardized rapid ageing. At each time point, seeds were subjected to hyperspectral imaging to obtain reflectance profiles from individual seeds. A standard germination test was performed, and we predicted that loss of germination was associated with a significant change in seed coat reflectance profiles. Forward linear discriminant analysis (LDA) was used to select the 10 spectral bands with the highest contribution to classifications of the three species. In all species, germination decreased from over 90% to below 20% in about 10-30days of experimental ageing. P50 values (equal to 50% germination) for each species were 19.3 (A. cowleana), 7.0 (B. prionotes) and 22.9 (C. calophylla) days. Based on independent validation of classifications of hyperspectral imaging data, we found that germination of Acacia and Corymbia seeds could be classified with over 85% accuracy, while it was about 80% for Banksia seeds. The selected spectral bands in each LDA-based classification were located near known pigment peaks involved in photosynthesis and/or near spectral bands used in published indices to predict chlorophyll or nitrogen content in leaves. The results suggested that seed germination may be successfully classified (predicted) based on reflectance in narrow spectral bands associated with the primary metabolism

  10. Light and temperature interaction in the photocontrol of germination of seeds in Ludwigia octovalvis.

    PubMed

    Wulff, R; Briceño, M

    1976-01-01

    The germination response of seeds of Ludwigia octovalvis (Jacq.) (=Jussiaea suffruticosa L.; Raven, 1963), to continuous light and to various types of intermittent irradiations is determined at 25, 30, 35 and 40° at different light intensities. At 25 and 40° intermittent irradiations are an effective substitute for continuous ones, while at 30 and 35° no promotion of germination is observed in the intermittent irradiations tested, except if the dark interval between light pulses is reduced to 1 min. Previous results obtained in the photocontrol of germination in this species are confirmed and extended to a variety of light cycles and intensities, indicating that the response to temperature is bimodal unless light is supplied continuously with high intensity, and that germination depends on light intensity more markedly in the temperature region of minimum germination (30-35°). As germination in this species is controlled by the red far-red system, hypothesis to account for the temperature dependence are based on the interaction between temperature and the reactions in which phytochrome is involved. PMID:24430746

  11. Germination and Plantlet Regeneration of Encapsulated Microshoots of Aromatic Rice (Oryza sativa L. Cv. MRQ 74)

    PubMed Central

    Taha, Rosna Mat; Saleh, Azani; Mahmad, Noraini; Hasbullah, Nor Azlina; Mohajer, Sadegh

    2012-01-01

    Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. In the present study, 3–5 mm microshoots of Oryza sativa L. Cv. MRQ 74 were used as explant sources for obtaining synthetic seeds. Microshoots were induced from stem explants on Murashige and Skoog (MS) medium supplemented with 1.5 mg/L benzylaminopurine (BAP). They were encapsulated in 3% (w/v) sodium alginate, 3% sucrose, 0.1 mg/L BAP, and 0.1 mg/L α-Naphthalene acetic acid (NAA). Germination and plantlet regeneration of the encapsulated seeds were tested by culturing them on various germination media. The effect of storage period (15–30 days) was also investigated. The maximum germination and plantlet regeneration (100.0%) were recorded on MS media containing 3% sucrose and 0.8% agar with and without 0.1 mg/L BAP. However, a low germination rate (6.67%) was obtained using top soil as a sowing substrate. The germination rate of the encapsulated microshoots decreased from 93.33% to 3.33% after 30 days of storage at 4°C in the dark. Therefore, further research is being done to improve the germination rate of the synthetic seeds. PMID:22919338

  12. Heat shock effects on seed germination of five Brazilian savanna species.

    PubMed

    Ribeiro, L C; Pedrosa, M; Borghetti, F

    2013-01-01

    Fire is considered an important factor in influencing the physiognomy, dynamics and composition of Neotropical savannas. Species of diverse physiognomies exhibit different responses to fire, such as population persistence and seed mortality, according to the fire frequency to which they are submitted. The aim of this study is to investigate the effects of heat shocks on seed germination of Anadenanthera macrocarpa (Benth.) Brenan, Dalbergia miscolobium Benth., Aristolochia galeata Mart. & Zucc., Kielmeyera coriacea (Spreng.) Mart. and Guazuma ulmifolia Lam., which are native species of the Brazilian savanna. The temperatures and exposure times to which the seeds were submitted were established according to data obtained in the field during a prescribed fire: 60 °C (10, 20 and 40 min), 80 °C (5, 10 and 20 min) and 100 °C (2, 5 and 10 min). Untreated seeds were used as controls. Seeds of A. galeata and K. coriacea showed high tolerance to most heat treatments, and seeds of A. macrocarpa showed a significant reduction in germination percentage after treatments of 80 °C and 100 °C. Treatments of 100 °C for 10 min reduced germination percentage for all species except G. ulmifolia, which has dormant seeds. For this species, germination was accelerated by heat treatments. The high temperatures applied did not interfere with the time to 50% germination (T(50) ) of the tolerant seeds. Seeds of the savanna species K. coriacea and A. galeata were more tolerant to heat shocks than seeds of the forest species A. macrocarpa. Guazuma ulmifolia, the forest species with seeds that germinate after heat shock, also occurs in savanna physiognomies. Overall, the high temperatures applied did not affect the germination rate of the tolerant seeds. PMID:22672775

  13. Comparison of germination and seed vigor of sunflower in two contaminated soils of different texture

    NASA Astrophysics Data System (ADS)

    Zhao, Xin; Han, Jaemaro; Lee, Jong Keun; Kim, Jae Young

    2014-05-01

    Phytoremediation as an emerging low-cost and ecologically friendly alternative to the conventional soil remediation technologies has gained a great deal of attention and into lots of research. As a kind of the methods that use of green plants to remediate heavy metals contaminated soils, the early growth status of plant seeds in the contaminated environmental directly affects the effect of phytoremediation. Germination test in the water (aqueous solution of heavy metal) is generally used for assessing heavy metal phytotoxicity and possibility of plant growth, but there is a limit. Because soil is commonly main target of phytoremediation, not the water. The bioavailability of heavy metals in the soil also depends on the texture. So soil texture is an important factor of phytoremediation effect. Sunflower is the representative species which have good tolerance to various heavy metals; furthermore, the seeds of sunflower can be used as the raw-material for producing bio-diesel. The objectives of this research were to investigate germination rate of sunflowers in various heavy metal contaminated soils and to compare the seedling vigor index (SVI) of sunflower in two contaminated soils of different texture. Sunflower (Helianthusannuus L.) seeds were obtained from a commercial market. In order to prove the soil texture effect on heavy metal contaminated soil, germination tests in soil were conducted with two different types of soil texture (i.e., loam soil and sandy loam soil) classified by soil textural triangle (defined by USDA) including representative soil texture of Korea. Germination tests in soil were conducted using KS I ISO 11260-1 (2005) for reference that sunflower seeds were incubated for 7 days in dark at 25 ± 1 Celsius degree. The target heavy metals are Nickel (Ni) and Zinc (Zn). The Ni and Zn concentrations were 0, 10, 50, 100, 200, 300, 500 mg-Ni/kg-dry soil, and 0, 10, 50, 100, 300, 500, 900 mg-Zn/kg-dry soil, respectively. After germination test for 7

  14. The design and testing of an electrolyte destratification system applied to a 96 V Alco 2200 battery

    NASA Astrophysics Data System (ADS)

    Nowak, D.; Tomantschger, K.

    1984-01-01

    A pump system for electrolyte destratification in off-the-shelf conventional lead acid batteries was designed and tested at various operating temperatures. The system requires no modification to the battery case. The pump is inserted through small (3 to 4 mm) holes in the battery case top. The system applied was to a 96 V ALCO 2200 battery. The charge time was cut in half, the water loss was minimized, and overall efficiencies for the modified ALCO 2200 increased. Leakage problems were experienced in some modules due to the deterioration of the glue which attaches the air-lift pump manifolds onto the battery cover. The tests were performed on a 48 V system and extrapolated to a 96 V system.

  15. Increase in Testing Efficiency through the Development of an IT-Based Adaptive Testing Tool for Competency Measurement Applied to a Health Worker Training Test Case

    ERIC Educational Resources Information Center

    Kleinhans, Janne; Schumann, Matthias

    2015-01-01

    In the context of education and training, competency measurement (CM) is a central challenge in competency management. For complex CMs, a compromise must be addressed between the time available and the number of dimensions to be measured or the quality of the measurements. Increasing the efficiency of existing tests for CMs therefore poses a key…

  16. Comparative sensory and proximate evaluation of spontaneously fermenting kunu-zaki made from germinated and ungerminated composite cereal grains.

    PubMed

    Oluwajoba, Solakunmi O; Akinyosoye, Felix A; Oyetayo, Olusegun V

    2013-07-01

    This study evaluated the sensory properties, proximate composition, and overall consumer acceptability of kunu-zaki using germinated and ungerminated Sorghum bicolor (sorghum), Pennisetum americanum (millet), and Digitaria exilis (acha) cereal grains. The three cereal grains were used in nongerminated and germinated composite and noncomposite proportions coded A (Acha), S (Sorghum), M (Millet), AS (Acha-Sorghum), AM (Acha-Millet), SM (Sorghum-Millet), ASG (Acha-Sorghum Germinated), AMG (Acha-Millet Germinated), and SMG (Sorghum-Millet Germinated). Proximate analysis determined the moisture content, ash, crude fiber, fat, and crude protein content of the fermented grains. The 9-point hedonic scale was used to judge the sensory parameters of taste, color, and aroma. The paired comparison test was used to judge consumer preference between kunu-zaki made from germinated grains and the ungerminated counterpart. Scores were statistically analyzed using the Kruskal-Wallis test in the SPSS analytical software package. Panelists ranked the ASG-coded drink highest in terms of taste and aroma, the AMG-coded drink highest in terms of color. SM ranked least in terms of taste; SMG ranked least in terms of aroma; and AM ranked the least in terms of color. Preference for each parameter was significantly different (P < 0.001). Panelists ranked overall preference for the drinks from the most liked to the least liked in the order ASG>AMG>A>AS>S>M>SMG>AM>SM. The overall preference for the drinks was also significantly different (P < 0.001). Panelists pairing both ungerminated drinks with the germinated drinks ranked the ungerminated drink AS as most preferred in terms of taste, color, and aroma above its germinated counterpart ASG with preference not significantly dependent on the parameters (P = 0.065 > 0.05). Ungerminated AM was also preferred above the germinated counterpart AMG in terms of taste, color, and aroma with preference not significantly dependent on parameters (P = 0

  17. 7 CFR 75.17 - Testing.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... applicant, tests may be made for kind, variety, germination, purity, weed seeds, disease pathogens... Official Seed Analysts (AOSA) or the International Seed Testing Association (ISTA) as requested by...

  18. 7 CFR 75.17 - Testing.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... applicant, tests may be made for kind, variety, germination, purity, weed seeds, disease pathogens... Official Seed Analysts (AOSA) or the International Seed Testing Association (ISTA) as requested by...

  19. 7 CFR 75.17 - Testing.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... applicant, tests may be made for kind, variety, germination, purity, weed seeds, disease pathogens... Official Seed Analysts (AOSA) or the International Seed Testing Association (ISTA) as requested by...

  20. 7 CFR 75.17 - Testing.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... applicant, tests may be made for kind, variety, germination, purity, weed seeds, disease pathogens... Official Seed Analysts (AOSA) or the International Seed Testing Association (ISTA) as requested by...

  1. 7 CFR 75.17 - Testing.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... applicant, tests may be made for kind, variety, germination, purity, weed seeds, disease pathogens... Official Seed Analysts (AOSA) or the International Seed Testing Association (ISTA) as requested by...

  2. Germination characteristics of Andropogon virginicus L

    SciTech Connect

    Farmer, R.E. Jr.; Cunningham, M.; Brown, J.E.

    1980-12-01

    The natural occurrence of broomsedge (Andropogon virginicus L.) as a pioneer species on orphan strip mines with acid soils (pH 3.0-4.0) and other areas of low fertility suggests that it may have value in revegetation systems for disturbed sites. This study was conducted to delineate seed dormancy and germination characteristics important to developing seeding procedures. Freshly collected seed from east Tennessee germinated to about 50 percent under light at 20-30/sup 0/C, but did not germinate at lower temperatures. If stored in a low-humidity, low-temperature environment, seed developed a deeper dormancy, which was broken by moist chilling. This chilling first enabled germination at high temperatures and in light; as chilling time increased, seed developed a capability for germination in the dark and at low temperatures. In a preliminary seeding trial on an acid (pH 4.0) minesoil, broomsedge survived and grew better than commonly used species such as Festuca arundinacea and Eragrostis curvula.

  3. [Seed germination of four tree species from the tropical dry forest of Valle del Cauca, Colombia].

    PubMed

    Vargas Figueroa, Jhon Alexander; Duque Palacio, Olga Lucía; Torres González, Alba Marina

    2015-03-01

    The ecological restoration strategies for highly threatened ecosystems such as the tropical dry forest, depend on the knowledge of limiting factors of biological processes for the different species. Some of these include aspects such as germination and seed longevity of typical species present in those forests. In this study, we evaluated the effect of light and temperature on seed germination of two Fabaceae (Samanea saman and Jacaranda caucana) and two Bignoniaceae (Pithecellobium dulce and Tabebuia rosea) species having potential use in restoration, and we analyzed the seed storage behavior of these species for a three months period. To study the light effect, four levels of light quality on seeds were used (photoperiod of 12 hours of white light, darkness and light enriched in red and far-red, both for an hour each day), and we combined them with three levels of alternated temperatures (20/25, 20/30 and 25/30*C-16/8h). For the storage behavior, two levels of seed moisture content particular for each species were used (low: 3.5-6.1% and high: 8.3-13.8%), with three storage temperatures (20, 5 and -20 degrees C) and two storage times (one and three months). The criterion for germination was radicle emergence which was measured in four replicates per treatment, and was expressed as percentage of germination (PG). There were significant differences in germination of Samanea saman and Jacaranda caucana among light and temperature treatments, with the lowest value in darkness treatments, whereas germination of Pithecellobium dulce and Tabebuia rosea did not differ between treatments (PG>90%). The most suitable temperature regime to promote germination in all species was 25/30 degrees C. These four species showed an orthodox seed storage behavior. We concluded that seeds of R dulce, J. caucana and T. rosea did not have an apparent influence of all light conditions tested in their germination response, which might confer advantages in colonization and establishment

  4. In vitro OECD test methods applied to screen the estrogenic effect of chemicals, used in Korea.

    PubMed

    Lee, Hee-Seok; Park, Eun-Jung; Han, Songyi; Oh, Gyeong-Yong; Kim, Min-Hee; Kang, Hui-Seung; Suh, Jin-Hyang; Oh, Jae-Ho; Lee, Kwang-Soo; Hwang, Myung-Sil; Moon, Guiim; Hong, Jin-Hwan; Hwang, In-Gyun

    2016-09-01

    In this study, 27 chemicals found in household products, which became an issue in Korea were screened for the agonistoc and antagonistic effects against human estrogen receptor using official Organization for Economic Cooperation and Development (OECD) in vitro assays, STTA assay using ERα-HeLa-9903 cell line and BG1Luc ER TA assay. In the case of human ER agonist screening by two assays, all tested chemicals did not show agonist effect against ER. In ER antagonist test by BG1Luc ER TA assay, five surfactants α-dodecyl-ω-hydroxypoly(oxyethylene), alcohols C16-18 ethoxylated, nonylphenol, ethoxylated, 3,6,9,12,15,18,21-heptaoxatritriacontan-1-ol, and α-dodecyl-ω-hydroxypoly(oxy-1,2-ethanediyl)) were found to exhibit weak antagonistic activities. The agonist/antagonist effects against human estrogen receptor of various chemicals, used in Korea by OECD test guideline are reported in this study. These results indicated that two OECD in vitro assays will can be applied in Korea by screening of agonistic/antagonistic effects against human ER of various chemicals. PMID:27317829

  5. Using scratch testing to measure the adhesion strength of calcium phosphate coatings applied to poly(carbonate urethane) substrates.

    PubMed

    Barnes, Dunstan; Johnson, Scott; Snell, Robert; Best, Serena

    2012-02-01

    Bioactive coatings are applied to components of modern orthopædic implants to improve the host tissue response to the implants. Such coatings cannot be applied to polymeric implants by high-temperature techniques, because the use of high temperatures may critically degrade the polymer substrate. Regardless of the coating technique that is used, the coating must be sufficiently well adhered to the underlying substrate to provide any practical benefit. This paper investigates the use of scratch testing to measure the adhesion strength of calcium phosphate (CaP) coatings that were applied to a poly(carbonate urethane) (PCU) substrate by an aqueous process at temperatures of 19, 28, 37, and 50 °C. This work represents the first time that scratch testing analysis has been used to study CaP coatings deposited by an aqueous, low-temperature process on to a polymer substrate. Scratch testing was shown to be a useful technique for obtaining comparative, rather than absolute, values of adhesion strength for hard coatings formed on a compliant substrate. Generally, the coating temperature was not found to influence the CaP-PCU adhesion strength. Although CaP coatings formed at 19 °C exhibited considerably lower adhesion strengths than CaP coatings formed at 28, 37, and 50 °C, this finding was attributable to the inconsistency of CaP coatings formed on the PCU substrates at 19 °C. The coating-substrate adhesion strength was measured for CaP coatings of four different coating ages (0, 1, 2, and 3 years). CaP coatings that were aged for 0, 1, or 2 years exhibited similar coating-substrate adhesion strengths to each other. In contrast, CaP coatings that were aged for 3 years demonstrated considerably lower coating-substrate adhesion strengths. The observed reduction in adhesion strength with age was thought to be attributable to suspected "drying out" of the CaP coatings. PMID:22301182

  6. Combining ability for germination traits in Jatropha curcas L.

    PubMed

    Islam, A K M Aminul; Anuar, Nurina; Yaakob, Zahira; Ghani, Jaharah A; Osman, Mohamad

    2013-01-01

    Six parents of Jatropha curcas were crossed in half diallel fashion, and the F 1s were evaluated to determine the combining ability for nine germination parameters. The ratio between general combining ability (GCA) and specific combining ability (SCA) variances indicated preponderance of additive gene action for all the characters except germination percentage, time of 50% germination, seedling length, and seedling vigor index. The parents P 1 and P 2 were the best general combiner for most of the characters studied. The cross P 1 × P 5 was the best specific combiner for speed of emergence, germination percentage, germination energy, germination index, and seedling vigor index, the cross P 2 × P 5 for mean germination time, time of 50% germination, and seedling length, and the cross P 4 × P 5 for number of days to first germination. The germination percentage varied from 58.06 to 92.76% among the parents and 53.43 to 98.96% among the hybrids. The highest germination (98.96%) was observed in hybrid P 2 × P 4, and none of the hybrids or parents showed 100% germination. The highest germination index (GI) and seedling vigor index (SVI) were found in hybrid P 1 × P 5 and P 2 × P 5, respectively. The results of this study provide clue for the improvement of Jatropha variety through breeding program. PMID:24222756

  7. Physiological and biochemical responses of rice seeds to phosphine exposure during germination.

    PubMed

    Niu, Xiaojun; Mi, Lina; Li, Yadong; Wei, Aishu; Yang, Zhiquan; Wu, Jiandong; Zhang, Di; Song, Xiaofei

    2013-11-01

    Rice seeds (Tianyou, 3618) were used to examine the physiological and biochemical responses to phosphine exposure during germination. A control (0 mg m(-3)) and four concentrations of phosphine (1.4 mg m(-3), 4.2 mg m(-3), 7.0 mg m(-3) and 13.9 mg m(-3)) were used to treat the rice seeds. Each treatment was applied for 90 min once per day for five days. The germination rate (GR); germination potential (GP); germination index (GI); antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); and lipid peroxidation measured through via malondialdehyde (MDA) were determined as indicators of the physiological and biochemical responses of the rice seeds to phosphine exposure. These indicators were determined once per day for five days. The results indicated that the GR, GP and GI of the rice seeds markedly decreased after phosphine exposure. The changes in the activities of the antioxidant enzymes due to the phosphine exposure were also significant. The exposure lowered the CAT and SOD activities and increased POD activity in the treated rice seeds compared with controls. The MDA content exhibited a slow increase trend with the increase of phosphine concentration. These results suggest that phosphine has inhibitory effects on seed germination. In addition, phosphine exposure caused oxidative stress in the seeds. The antioxidant enzymes could play a pivotal role against oxidative injury. Overall, the effect of phosphine on rice seeds is different from what has been reported previously for insects and mammals. PMID:23992639

  8. Seed Germination Ecology of the Cold Desert Annual Isatis violascens (Brassicaceae): Two Levels of Physiological Dormancy and Role of the Pericarp.

    PubMed

    Zhou, Yuan M; Lu, Juan J; Tan, Dun Y; Baskin, Carol C; Baskin, Jerry M

    2015-01-01

    The occurrence of various species of Brassicaceae with indehiscent fruits in the cold deserts of NW China suggests that there are adaptive advantages of this trait. We hypothesized that the pericarp of the single-seeded silicles of Isatis violascens restricts embryo expansion and thus prevents germination for 1 or more years. Thus, our aim was to investigate the role of the pericarp in seed dormancy and germination of this species. The effects of afterripening, treatment with gibberellic acid (GA3) and cold stratification on seed dormancy-break were tested using intact silicles and isolated seeds, and germination phenology was monitored in an experimental garden. The pericarp has a role in mechanically inhibiting germination of fresh seeds and promotes germination of nondormant seeds, but it does not facilitate formation of a persistent seed bank. Seeds in silicles in watered soil began to germinate earlier in autumn and germinated to higher percentages than isolated seeds. Sixty-two percent of seeds in the buried silicles germinated by the end of the first spring, and only 3% remained nongerminated and viable. Twenty to twenty-five percent of the seeds have nondeep physiological dormancy (PD) and 75-80% intermediate PD. Seeds with nondeep PD afterripen in summer and germinate inside the silicles in autumn if the soil is moist. Afterripening during summer significantly decreased the amount of cold stratification required to break intermediate PD. The presence of both nondeep and intermediate PD in the seed cohort may be a bet-hedging strategy. PMID:26513241

  9. The community-level effect of light on germination timing in relation to seed mass: a source of regeneration niche differentiation.

    PubMed

    Zhang, Chunhui; Willis, Charles G; Burghardt, Liana T; Qi, Wei; Liu, Kun; Souza-Filho, Paulo Roberto de Moura; Ma, Zhen; Du, Guozhen

    2014-11-01

    Within a community, species may germinate at different times so as to mitigate competition and to take advantage of different aspects of the seasonal environment (temporal niche differentiation). We illustrated a hypothesis of the combined effects of abiotic and biotic competitive factors on germination timing and the subsequent upscale effects on community assembly. We estimated the germination timing (GT) for 476 angiosperm species of the eastern Tibetan Plateau grasslands under two light treatments in the field: high (i.e. natural) light and low light. We also measured the shift in germination timing (SGT) across treatments for all species. Furthermore, we used phylogenetic comparative methods to test if GT and SGT were associated with seed mass, an important factor in competitive interactions. We found a significant positive correlation between GT and seed mass in both light treatments. Additionally, small seeds (early germinating seeds) tended to germinate later and large seeds (late germinating seeds) tended to germinate earlier under low light vs high light conditions. Low light availability can reduce temporal niche differentiation by increasing the overlap in germination time between small and large seeds. In turn, reduced temporal niche differentiation may increase competition in the process of community assembly. PMID:25081830

  10. Seed Germination Ecology of the Cold Desert Annual Isatis violascens (Brassicaceae): Two Levels of Physiological Dormancy and Role of the Pericarp

    PubMed Central

    Tan, Dun Y.; Baskin, Carol C.; Baskin, Jerry M.

    2015-01-01

    The occurrence of various species of Brassicaceae with indehiscent fruits in the cold deserts of NW China suggests that there are adaptive advantages of this trait. We hypothesized that the pericarp of the single-seeded silicles of Isatis violascens restricts embryo expansion and thus prevents germination for 1 or more years. Thus, our aim was to investigate the role of the pericarp in seed dormancy and germination of this species. The effects of afterripening, treatment with gibberellic acid (GA3) and cold stratification on seed dormancy-break were tested using intact silicles and isolated seeds, and germination phenology was monitored in an experimental garden. The pericarp has a role in mechanically inhibiting germination of fresh seeds and promotes germination of nondormant seeds, but it does not facilitate formation of a persistent seed bank. Seeds in silicles in watered soil began to germinate earlier in autumn and germinated to higher percentages than isolated seeds. Sixty-two percent of seeds in the buried silicles germinated by the end of the first spring, and only 3% remained nongerminated and viable. Twenty to twenty-five percent of the seeds have nondeep physiological dormancy (PD) and 75–80% intermediate PD. Seeds with nondeep PD afterripen in summer and germinate inside the silicles in autumn if the soil is moist. Afterripening during summer significantly decreased the amount of cold stratification required to break intermediate PD. The presence of both nondeep and intermediate PD in the seed cohort may be a bet-hedging strategy. PMID:26513241

  11. Towards objective evaluation of balance in the elderly: validity and reliability of a measurement instrument applied to the Tinetti test.

    PubMed

    Panella, Lorenzo; Tinelli, Carmine; Buizza, Angelo; Lombardi, Remo; Gandolfi, Roberto

    2008-03-01

    The aim of the present study was the validation of an instrument for evaluating balance, applied to the Tinetti test. Trunk inclination was measured by inclinometers during the Tinetti test in 163 healthy participants scoring 28/28 in the Tinetti scale (controls: 92 women, 71 men; age 19-85 years), and 111 residents in old people's homes, able to autonomously perform the test, but scoring less than 28/28 (test group: 78 women, 33 men; age 55-96 years). Trunk inclination was quantified by 20 parameters, whose standardized values were summed and provided an overall performance index (PTOT). PTOT reliability was evaluated by Cronbach's alpha, and its validity by item scale correlation, discriminant validity and concurrent validity. Influence of age and sex was assessed by a logistic regression model. Repeatable and consistent measurements were obtained (Cronbach's alpha=0.88). Parameter distribution was significantly different in controls and patients (P<0.001). Optimal PTOT threshold for discriminating between normal and abnormal performance (153.9/200) corresponded to sensitivity of 88.3%, specificity of 84.7% and area under the receiver operating characteristics curve of 0.93. PTOT correlated with the Tinetti scale score, its partial, balance-related score and Barthel's Index, but not with the Mini Mental State score. PTOT correlated with age and level of performance but not with sex; correlation with age did not prevent the possibility of discriminating between different levels of performance and between normal and abnormal performance. The instrument provided objective discrimination between different performance levels, in particular, between normal and altered performance. PMID:18277206

  12. Complexes of D-type cyclins with CDKs during maize germination.

    PubMed

    Godínez-Palma, Silvia K; García, Elpidio; Sánchez, María de la Paz; Rosas, Fernando; Vázquez-Ramos, Jorge M

    2013-12-01

    The importance of cell proliferation in plant growth and development has been well documented. The majority of studies on basic cell cycle mechanisms in plants have been at the level of gene expression and much less knowledge has accumulated in terms of protein interactions and activation. Two key proteins, cyclins and cyclin-dependent kinases (CDKs) are fundamental for cell cycle regulation and advancement. Our aim has been to understand the role of D-type cyclins and type A and B CDKs in the cell cycle taking place during a developmental process such as maize seed germination. Results indicate that three maize D-type cyclins-D2;2, D4;2, and D5;3-(G1-S cyclins by definition) bind and activate two different types of CDK-A and B1;1-in a differential way during germination. Whereas CDKA-D-type cyclin complexes are more active at early germination times than at later times, it was surprising to observe that CDKB1;1, a supposedly G2-M kinase, bound in a differential way to all D-type cyclins tested during germination. Binding to cyclin D2;2 was detectable at all germination times, forming a complex with kinase activity, whereas binding to D4;2 and D5;3 was more variable; in particular, D5;3 was only detected at late germination times. Results are discussed in terms of cell cycle advancement and its importance for seed germination. PMID:24127516

  13. Germination of stress-tolerant Eucalyptus pollen.

    PubMed

    Heslop-Harrison, J; Heslop-Harrison, Y

    1985-02-01

    Earlier reports have indicated that the pollen of Eucalyptus is mechanically robust and unusually resistant to the osmotic stress imposed by immersion in water. We have investigated some of the features of the germination mechanism in the pollen of E. rhodantha with a view to clarifying the role of pollen-wall specializations in determining this resistance. Cultured in vitro, the pollen showed erratic germination, with a scatter of germination times up to 24 h. This was associated with variation between individual grains in the rate of hydration and dispersal of the pectins of the oncus, the thickened outer component of the intine present at each aperture. The oncus is itself differentiated, with a refractive outer layer lying within a sporopollenin operculum and itself overlying the protein-bearing layer of the intine. The outer layer, interpreted as a compacted pectin, undergoes only slow dissolution in aqueous media after the lifting of the operculum, and it is this that apparently protects the grain from the effects of short-term osmotic stress. The rate of dissolution varies between grains, possibly as a consequence of minor differences in developmental rate in the final stages of differentiation in the anther, and this contributes to the wider scatter of germination times. The dehydrated pollen gave one-third of the potential germination after 24 h exposure to 60 degrees C, and a small proportion survived 24 h at 70 degrees C. This degree of heat tolerance must primarily reflect properties of the protoplast of the vegetative cell, not examined in the present study; but the wall specializations may well provide a guard against extreme desiccation, and it is noteworthy that the function of the germination mechanism is not prejudiced by exposure to high temperatures. PMID:4019590

  14. Interaction of microwaves and germinating seeds

    SciTech Connect

    Shafer, F.L.

    1987-01-01

    The preliminary investigation measured the internal metabolic process by ATP production. Leakage of ions and organic material from germinating seeds indicated that membranes are a target of microwaves and heat. Electron photo-micrographs showed an increase in damage to membranes as heat and microwave treatments were increased. The second phase of this investigation was concerned with determining some of the biological activity at the initiation of germination of wheat seed, Triticum aestivum L., using a resonating microwave cavity oscillating at 9.3 GHz as a probe. Direct current conductivity measurements were also made on the seeds as a means of confirming the observations made with the microwave cavity.

  15. Measuring Total and Germinable Spore Populations

    NASA Technical Reports Server (NTRS)

    Noell, A.C.; Yung, P.T.; Yang, W.; Lee, C.; Ponce, A.

    2011-01-01

    It has been shown that bacterial endospores can be enumerated using a microscopy based assay that images the luminescent halos from terbium ions bound to dipicolinic acid, a spore specific chemical marker released upon spore germination. Further development of the instrument has simplified it towards automation while at the same time improving image quality. Enumeration of total spore populations has also been developed allowing measurement of the percentage of viable spores in any population by comparing the germinable/culturable spores to the total. Percentage viability will allow a more quantitative comparison of the ability of spores to survive across a wide range of extreme environments.

  16. Measuring Total and Germinable Spore Populations

    NASA Astrophysics Data System (ADS)

    Noell, A. C.; Yung, P. T.; Yang, W.; Ponce, A.; Lee, C.

    2011-10-01

    It has been shown that bacterial endospores can be enumerated using a microscopy based assay that images the luminescent halos from terbium ions bound to dipicolinic acid, a spore specific chemical marker released upon spore germination. Further development of the instrument has simplified it towards automation while at the same time improving image quality. Enumeration of total spore populations has also been developed allowing measurement of the percentage of viable spores in any population by comparing the germinable/culturable spores to the total. Percentage viability will allow a more quantitative comparison of the ability of spores to survive across a wide range of extreme environments.

  17. Applying User Input to the Design and Testing of an Electronic Behavioral Health Information System for Wraparound Care Coordination

    PubMed Central

    Bruns, Eric J.; Hyde, Kelly L.; Sather, April; Hook, Alyssa; Lyon, Aaron R.

    2015-01-01

    Health information technology (HIT) and care coordination for individuals with complex needs are high priorities for quality improvement in health care. However, there is little empirical guidance about how best to design electronic health record systems and related technologies to facilitate implementation of care coordination models in behavioral health, or how best to apply user input to the design and testing process. In this paper, we describe an iterative development process that incorporated user/stakeholder perspectives at multiple points and resulted in an electronic behavioral health information system (EBHIS) specific to the wraparound care coordination model for youth with serious emotional and behavioral disorders. First, we review foundational HIT research on how EBHIS can enhance efficiency and outcomes of wraparound that was used to inform development. After describing the rationale for and functions of a prototype EBHIS for wraparound, we describe methods and results for a series of six small studies that informed system development across four phases of effort – predevelopment, development, initial user testing, and commercialization – and discuss how these results informed system design and refinement. Finally, we present next steps, challenges to dissemination, and guidance for others aiming to develop specialized behavioral health HIT. The research team's experiences reinforce the opportunity presented by EBHIS to improve care coordination for populations with complex needs, while also pointing to a litany of barriers and challenges to be overcome to implement such technologies. PMID:26060099

  18. Serum corticosterone as a quantitative test of the phlogistic potency of various agents topically applied in the rat.

    PubMed

    Giagnoni, G; Marsi, A; Parolaro, D; Sala, M; Gori, E

    1976-12-01

    The application into the rat conjunctiva of various phlogistic agents, such as croton oil, mustard oil and formaldehyde, elicits an increase of serum corticosterone linearly related to the log of the applied concentrations, so that from their parallelized regression lines it is possible to calculate the phlogistic potency of each tested agent in reference to croton oil. The time kinetic of such an increase (elicited by croton oil) is compared with that of two other parameters previously adopted as indirect quantitative indices of the phlogosis: the adrenal ascorbic acid depletion and the liver tyrosine-alpha-ketoglutarate transaminase increase. Serum corticosterone is shown to be the quickest and the most sensitive of the adopted indices, even if the phlogistic potency of the tested agents and the precision of these evaluations substantially coincides whatsoever the index adopted. Finally the pathways of adrenocortical activation are investigated and it is shown that the activation may be peripherally blocked by topical application of corticosteroids (but not of local anesthetics) and centrally by hypophysectomy or parenteral administration of pentobarbital plus morphine. PMID:13751

  19. Applying User Input to the Design and Testing of an Electronic Behavioral Health Information System for Wraparound Care Coordination.

    PubMed

    Bruns, Eric J; Hyde, Kelly L; Sather, April; Hook, Alyssa N; Lyon, Aaron R

    2016-05-01

    Health information technology (HIT) and care coordination for individuals with complex needs are high priorities for quality improvement in health care. However, there is little empirical guidance about how best to design electronic health record systems and related technologies to facilitate implementation of care coordination models in behavioral health, or how best to apply user input to the design and testing process. In this paper, we describe an iterative development process that incorporated user/stakeholder perspectives at multiple points and resulted in an electronic behavioral health information system (EBHIS) specific to the wraparound care coordination model for youth with serious emotional and behavioral disorders. First, we review foundational HIT research on how EBHIS can enhance efficiency and outcomes of wraparound that was used to inform development. After describing the rationale for and functions of a prototype EBHIS for wraparound, we describe methods and results for a series of six small studies that informed system development across four phases of effort-predevelopment, development, initial user testing, and commercialization-and discuss how these results informed system design and refinement. Finally, we present next steps, challenges to dissemination, and guidance for others aiming to develop specialized behavioral health HIT. The research team's experiences reinforce the opportunity presented by EBHIS to improve care coordination for populations with complex needs, while also pointing to a litany of barriers and challenges to be overcome to implement such technologies. PMID:26060099

  20. Accumulation of long-lived mRNAs associated with germination in embryos during seed development of rice.

    PubMed

    Sano, Naoto; Ono, Hanako; Murata, Kazumasa; Yamada, Tetsuya; Hirasawa, Tadashi; Kanekatsu, Motoki

    2015-07-01

    Mature dry seeds contain translatable mRNAs called long-lived mRNAs. Early studies have shown that protein synthesis during the initial phase of seed germination occurs from long-lived mRNAs, without de novo transcription. However, the gene expression systems that generate long-lived mRNAs in seeds are not well understood. To examine the accumulation of long-lived mRNAs in developing rice embryos, germination tests using the transcriptional inhibitor actinomycin D (Act D) were performed with the Japonica rice cultivar Nipponbare. Although over 70% of embryos at 10 days after flowering (DAF) germinated in the absence of the inhibitor, germination was remarkably impaired in embryos treated with Act D. In contrast, more than 70% of embryos at 20, 25, 30 and 40 DAF germinated in the presence of Act D. The same results were obtained when another cultivar, Koshihikari, was used, indicating that the long-lived mRNAs required for germination predominantly accumulate in embryos between 10 and 20 DAF during seed development. RNA-Seq identified 529 long-lived mRNA candidates, encoding proteins such as ABA, calcium ion and phospholipid signalling-related proteins, and HSP DNA J, increased from 10 to 20 DAF and were highly abundant in 40 DAF embryos of Nipponbare and Koshihikari. We also revealed that these long-lived mRNA candidates are clearly up-regulated in 10 DAF germinating embryos after imbibition, suggesting that the accumulation of these mRNAs in embryos is indispensable for the induction of germination. The findings presented here may facilitate in overcoming irregular seed germination or producing more vigorous seedlings. PMID:25941326

  1. Germination of Acacia harpophylla (Brigalow) seeds in relation to soil water potential: implications for rehabilitation of a threatened ecosystem

    PubMed Central

    Kailichova, Yolana; Baumgartl, Thomas

    2014-01-01

    Initial soil water conditions play a critical role when seeding is the primary approach to revegetate post-mining areas. In some semi-arid climates, such as the Brigalow Belt Bioregion in eastern Australia, extensive areas are affected by open-cut mining. Together with erratic rainfall patterns and clayey soils, the Brigalow Belt denotes a unique biome which is representative of other water-limited ecosystems worldwide. Apart from other environmental stressors, germination is governed by the water potential of the surrounding soil material. While previous studies have confirmed the high tolerance of Brigalow (Acacia harpophylla) seeds to a broad range of temperature and salinity, the question of how soil water potential triggers seed germination remains. In this study, we used three replicates of 50 seeds of Brigalow to investigate germination in relation to water potential as an environmental stressor. Solutions of Polyethylene Glycol (PEG 6000) were applied to expose seeds to nine osmotic water potentials ranging from soil water saturation (0 MPa) and field capacity (−.01 to −.03 MPa) to the permanent wilting point (−1.5 MPa). We measured germinability (number of germinated seeds relative to total number of seeds per lot) and mean germination time (mean time required for maximum germination of a seed lot) to quantify germination. Based on the empirical data of the germination we estimated the parameters of the hydrotime model which simulates timing and success of seed emergence. Our findings indicate that Brigalow seeds are remarkably tolerant to water stress, with germination being observed at a water potential as low as −1.5 MPa. Likewise, the average base water potential of a seed population (hydrotime model) was very low and ranged between −1.533 and −1.451 MPa. In general, Brigalow seeds germinate opportunistically over a broad range of abiotic conditions related to temperature, salinity, and water availability. Direct seeding and germination

  2. Germination of Acacia harpophylla (Brigalow) seeds in relation to soil water potential: implications for rehabilitation of a threatened ecosystem.

    PubMed

    Arnold, Sven; Kailichova, Yolana; Baumgartl, Thomas

    2014-01-01

    Initial soil water conditions play a critical role when seeding is the primary approach to revegetate post-mining areas. In some semi-arid climates, such as the Brigalow Belt Bioregion in eastern Australia, extensive areas are affected by open-cut mining. Together with erratic rainfall patterns and clayey soils, the Brigalow Belt denotes a unique biome which is representative of other water-limited ecosystems worldwide. Apart from other environmental stressors, germination is governed by the water potential of the surrounding soil material. While previous studies have confirmed the high tolerance of Brigalow (Acacia harpophylla) seeds to a broad range of temperature and salinity, the question of how soil water potential triggers seed germination remains. In this study, we used three replicates of 50 seeds of Brigalow to investigate germination in relation to water potential as an environmental stressor. Solutions of Polyethylene Glycol (PEG 6000) were applied to expose seeds to nine osmotic water potentials ranging from soil water saturation (0 MPa) and field capacity (-.01 to -.03 MPa) to the permanent wilting point (-1.5 MPa). We measured germinability (number of germinated seeds relative to total number of seeds per lot) and mean germination time (mean time required for maximum germination of a seed lot) to quantify germination. Based on the empirical data of the germination we estimated the parameters of the hydrotime model which simulates timing and success of seed emergence. Our findings indicate that Brigalow seeds are remarkably tolerant to water stress, with germination being observed at a water potential as low as -1.5 MPa. Likewise, the average base water potential of a seed population (hydrotime model) was very low and ranged between -1.533 and -1.451 MPa. In general, Brigalow seeds germinate opportunistically over a broad range of abiotic conditions related to temperature, salinity, and water availability. Direct seeding and germination of native

  3. Germins: A Diverse Protein Family Important For Crop Improvement

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The germin protein family is comprised of two main subgroups in plants, oxalate oxidases (OXOs) and germin-like proteins (GLPs). These proteins are implicated in a variety of plant processes including germination, development, pollen formation, and response to abiotic and biotic stress. Here, we exa...

  4. Standardizing germination protocols for diverse raspberry and blackberry species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most Rubus species exhibit delayed or poor germination because of a deep double dormancy. The objective of this study was to improve Rubus seed germination protocols by defining the seed characteristics of diverse Rubus species and determining scarification and germination requirements. Seeds of fie...

  5. Effect of germination on bioactive compounds of soybean (Glycine max)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Germination is the practice of soaking, draining, and keeping seeds until they produce sprouts. The increasing interest in functional and healthy food products has promoted the use of germinated soybean flour in the manufacture of foods for human consumption. It is well known that germination induce...

  6. An improved process for high nutrition of germinated brown rice production: Low-pressure plasma.

    PubMed

    Chen, Hua Han; Chang, Hung Chia; Chen, Yu Kuo; Hung, Chien Lun; Lin, Su Yi; Chen, Yi Sheng

    2016-01-15

    Brown rice was exposed to low-pressure plasma ranging from 1 to 3kV for 10min. Treatment of brown rice in low-pressure plasma increases the germination percentage, seedling length, and water uptake in laboratory germination tests. Of the various treatments, 3-kV plasma exposure for 10min yielded the best results. In germinating brown rice, α-amylase activity was significantly higher in treated groups than in controls. The higher enzyme activity in plasma-treated brown rice likely triggers the rapid germination and earlier vigor of the seedlings. Low-pressure plasma also increased gamma-aminobutyric acid (GABA) levels from ∼19 to ∼28mg/100g. In addition, a marked increase in the antioxidant activity of brown rice was observed with plasma treatments compared to controls. The main finding of this study indicates that low-pressure plasma is effective at enhancing the growth and GABA accumulation of germinated brown rice, which can supply high nutrition to consumer. PMID:26258710

  7. Biotransformation of constituents of essential oils by germinating wheat seed.

    PubMed

    Dudai, N; Larkov, O; Putievsky, E; Lerner, H R; Ravid, U; Lewinsohn, E; Mayer, A M

    2000-11-01

    Wheat seeds, when exposed to essential oils, are able to metabolise certain monoterpenes. The actual amounts of the compounds and their derivatives in the endosperm and embryo of wheat seeds, after exposure to the monoterpenes were determined. Neral and geranial, which are the constituents of citral, are reduced and oxidised to the corresponding alcohols and acids. Similarly citronellal, pulegone and carvacrol are converted partly to the corresponding reduction and oxidation products. The aromatic compound vanillin is partly reduced to vanillyl alcohol or oxidised to vanillic acid. In all cases it seems that part of the compounds applied are degraded, as indicated by the inability to account for all the compounds, which were supplied to the germinated seeds. In most cases the derivatives of the essential oil applied were less toxic than the parent compound. The possible role of non-specific enzymes by which the compounds are oxidised or reduced is discussed. PMID:11140596

  8. Intensity of regionally applied tastes in relation to administration method: an investigation based on the "taste strips" test.

    PubMed

    Manzi, Brian; Hummel, Thomas

    2014-02-01

    To compare various methods to apply regional taste stimuli to the tongue. "Taste strips" are a clinical tool to determine gustatory function. How a patient perceives the chemical environment in the mouth is a result of many factors such as taste bud distribution and interactions between the cranial nerves. To date, there have been few studies describing the different approaches to administer taste strips to maximize taste identification accuracy and intensity. This is a normative value acquisition pilot and single-center study. The investigation involved 30 participants reporting a normal sense of smell and taste (18 women, 12 men, mean age 33 years). The taste test was based on spoon-shaped filter paper strips impregnated with four taste qualities (sweet, sour, salty, and bitter) at concentrations shown to be easily detectable by young healthy subjects. The strips were administered in three methods (held stationary on the tip of the tongue, applied across the tongue, held in the mouth), resulting in a total of 12 trials per participant. Subjects identified the taste from a list of four descriptors, (sweet, sour, salty, bitter) and ranked the intensity on a scale from 0 to 10. Statistical analyses were performed on the accuracy of taste identification and rated intensities. The participants perceived in order of most to least intense: salt, sour, bitter, sweet. Of the four tastes, sour consistently was least accurately identified. Presenting the taste strip inside the closed mouth of the participants produced the least accurate taste identification, whereas moving the taste strip across the tongue led to a significant increase in intensity for the sweet taste. In this study of 30 subjects at the second concentration, optimized accuracy and intensity of taste identification was observed through administration of taste strips laterally across the anterior third of the extended tongue. Further studies are required on more subjects and the additional concentrations

  9. Software Tools for Weed Seed Germination Modeling

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The next generation of weed seed germination models will need to account for variable soil microclimate conditions. In order to predict this microclimate environment we have developed a suite of individual tools (models) that can be used in conjunction with the next generation of weed seed germinati...

  10. Interspecific Variations in Seed Germination of Corylopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was initiated to investigate the difference in germination pattern between C. coreana Uyeki and C. sinensis var. calvescens Rehder & E. H. Wilson responding to a warm (WS) and cold stratification (CS), and to study the effect of different WS temperatures interacting with different duratio...

  11. Fire Effects on Invasive Weed Seed Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Restoring historic fire regimes is often beneficial to rangeland structure and function. However, understanding of interactions between fire and invasive weeds is limited. We designed an experiment to determine fire effects on germination of soil surface-deposited seeds of the invasive weeds Bromu...

  12. In vitro corrosion testing of PVD coatings applied to a surgical grade Co-Cr-Mo alloy.

    PubMed

    Bolton, J; Hu, X

    2002-06-01

    Toxic effects and biological reaction of metallic corrosion and wear products are an important concern for metal on metal artificial joints. Corrosion tests were conducted to study the susceptibility to pitting and localized corrosion, with three coatings, CrN, TiN and DLC, applied to a wrought high carbon Co-Cr-Mo alloy substrate material. Corrosion testing involved the measurement of potential time transients during immersion in a physiological solution and cyclic polarization of specimen potentials into the transpassive range followed by reversal of the potential to scan in the cathodic direction to regain the rest potential E(rest). Resistance to pitting and localized corrosion was assessed by determining the transpassive breakdown potential E(bd) and if any hysteresis generated during the reverse cyclic scan may have caused crossover with the original anodic scan. Three different surface coating conditions were tested namely: (1) as-coated, (2) polished, and (3) indented to penetrate the coating by diamond pyramid hardness indentor. Results showed that all three coatings produced significant improvements in corrosion resistance compared to performance of the wrought cobalt alloy but that some corrosive attack to both the CrN and TiN coatings occurred and some risk of attack to the cobalt alloy substrate existed due to coating defects or when damage to the coating occurred. TiN coatings were highly effective in preventing corrosion provided they were thick enough to produce complete coverage. Thin TiN coatings displayed some tendency to encourage localized attack of the cobalt alloy at coating defects or where the coating suffered mechanical damage. CrN coatings underwent transpassive breakdown more easily and some degree of pitting at defects within the coating was observed, especially when the CrN coating was polished before the test. No corrosive attack of the cobalt alloy substrate was observed when the CrN coating was mechanically damaged by indentation

  13. Growth, Sporulation, and Germination of Clostridium perfringens in Media of Controlled Water Activity1

    PubMed Central

    Kang, Chunghee K.; Woodburn, Margy; Pagenkopf, Andrea; Cheney, Roberta

    1969-01-01

    Requirements in terms of water activity (aw) for the growth, sporulation, and germination of Clostridium perfringens were determined. Strain A48 was used in all phases, and in addition either NCTC 8239 or NCTC 8797 was used for growth, sporulation, and germination studies. The desired aw of the test media was obtained by the addition of one of three solutes: glycerol, sucrose, or sodium chloride. The freezing point depression method was used to determine the aw. The basal medium for growth and germination was Fluid Thioglycollate Medium. It had an aw of 0.995 and produced maximum growth and fastest growth rate among the six levels of aw tested. The lowest aw supporting growth and germination of C. perfringens was between 0.97 and 0.95 in the test media made with sucrose or sodium chloride and 0.93 or below in the test media adjusted with glycerol. Spore production by C. perfringens in Ellner's or modified medium required a higher aw than growth. PMID:4313168

  14. Cheatgrass germination at three seed maturity stages from five plant communities in northwestern Nevada

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The invasive exotic plant cheatgrass (Bromus tectorum), has invaded numerous plant communities throughout the Intermountain West. Our goal was to test whether cheatgrass seed in different phenotypic stages and site characteristics differ in germination. Cheatgrass seed from sites dominated by Wyom...

  15. Smoke-induced seed germination in California chaparral

    USGS Publications Warehouse

    Keeley, J.E.; Fotheringham, C.J.

    1998-01-01

    The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that smoke also induces germination in these same species. Smoke is highly effective, often inducing 100% germination in deeply dormant seed populations with 0% control germination. Smoke induces germination both directly and indirectly by aqueous or gaseous transfer from soil to seeds. Neither nitrate nor ammonium ions were effective in stimulating germination of smoke-stimulated species, nor were most of the quantitatively important gases generated by biomass smoke. Nitrogen dioxide, however, was very effective at inducing germination in Caulanthus heterophyllus (Brassicaceae), Emmenanthe penduliflora (Hydrophyllaceae), Phacelia grandiflora (Hydrophyllaceae), and Silene multinervia (Caryophyllaceae). Three species, Dendromecon rigida (Papaveraceae), Dicentra chrysantha, and Trichostema lanatum (Lamiaceae), failed to germinate unless smoke treatment was coupled with prior treatment of 1 yr soil storage. Smoke-stimulated germination was found in 25 chaparral species, representing 11 families, none of which were families known for heat-shock-stimulated germination. Seeds of smoke-stimulated species have many analogous characteristics that separate them from most heat-shock-stimulated seeds, including: (1) outer seed coats that are highly textured, (2) a poorly developed outer cuticle, (3) absence of a dense palisade tissue in the seed coat, and (4) a subdermal membrane that is semipermeable, allowing water passage but blocking entry of large (molecular mass > 500) solutes. Tentative evidence suggests that permeability characteristics of this subdermal layer are altered by

  16. Chemical inhibitors of viviparous germination in the fruit of watermelon.

    PubMed

    Kobayashi, Yoshiki; Nabeta, Kensuke; Matsuura, Hideyuki

    2010-09-01

    It is well known that the seeds of watermelon [Citrullus lanatus (Thunb.) Matsum and Nakai] have a high potential to germinate when the fruit has ripened. When removed from the mature fruit, the seeds can germinate under appropriate conditions. However, it is unclear why they cannot germinate in the flesh of the fruit. Here, we show that cis-ABA and its β-D-glucopyranosyl ester (ABA-β-GE) accumulate in the flesh of the fruit at levels high enough to inhibit seed germination. This result indicates the existence of chemical factors that inhibit viviparous seed germination of watermelon. PMID:20630986

  17. Test-retest reliability of a new technique with pressure algometry applied to teeth in healthy Chinese individuals.

    PubMed

    Liu, Ran; Gu, Xinyu; Zhang, Jinglu; Yu, Linfeng; Chen, Wenjing; Wang, Kelun; Svensson, Peter

    2016-06-01

    Pressure pain thresholds (PPTs) have been shown to be useful measures of mechanical pain sensitivity in deep tissues. However, clinical methods for measuring mechanical allodynia or hyperalgesia in teeth have not been reported. The aim of this study was to assess the reliability of PPTs in periodontal ligament of healthy Chinese participants. Twenty healthy young adults participated. Pressure pain thresholds were measured at six teeth and in two directions. The tests included three consecutive trials, in two separate sessions, which were performed on the first day by one examiner. After 1-3 wk, an identical protocol was carried out by two examiners, also in two separate sessions. There were no significant differences between repeated measures for all teeth. The PPTs had excellent reliability with high intraclass coefficients (ICCs) across different sessions (ICC: 0.871-0.956), days (ICC: 0.879-0.951), and examiners (ICC: 0.845-0.950). Pressure pain thresholds applied to the teeth have excellent intra- and inter-examiner agreement in healthy participants. This method may be proposed as an easy and reliable technique to assess mechanical pain sensitivity (e.g. mechanical allodynia and hyperalgesia) in the periodontal ligament, which is associated with endodontic or periodontal conditions. PMID:27017942

  18. NDT testing by holographic interferometry applied to the structural diagnostic of artwork conservations by means of sound wave excitation

    NASA Astrophysics Data System (ADS)

    Vincitorio, Fabio; Ramil, Alberto; López, Ana J.; Saavedra, Emilio; Yáñez, Armando

    2008-06-01

    Techniques based on holographic interferometry have achieved a mature state of non destructive testing applications in industry and nowadays they are rising as interesting and promising tools in the field of conservation practices; giving information about the condition of structural integration of artworks. In the practice of these techniques it is necessary to generate a relative deformation in the object under study. Depending of the characteristics of the artwork, different methods may be used to achieve the desired displacement; being thermal excitation by means of filament lamps and wave sounds generated by speakers the most common. By applying these methods the deformation process usually involves a large area of the object, which limits the information obtained of a finite region. However, the use of a wave sound emitter of small dimensions, like a low power monotone buzzer, allows to decrease the affected area and to obtain information about the structural integrity of localized points of the surface. In the present study conventional double exposure double way holographic technique based on holographic films was used to obtain an out of plain deformation pattern caused by a sound emitter in an oil painting which has suffered heavy structural damage. Optimization of the excitation sound wave characteristics (frequency and amplitude) and the adjustment and calibration of the experimental set up, in order to obtain precise information about the physical and mechanical integrity of localized points of the painting are reported.

  19. Requirements for in vitro germination of Paenibacillus larvae spores.

    PubMed

    Alvarado, Israel; Phui, Andy; Elekonich, Michelle M; Abel-Santos, Ernesto

    2013-03-01

    Paenibacillus larvae is the causative agent of American foulbrood (AFB), a disease affecting honey bee larvae. First- and second-instar larvae become infected when they ingest food contaminated with P. larvae spores. The spores then germinate into vegetative cells that proliferate in the midgut of the honey bee. Although AFB affects honey bees only in the larval stage, P. larvae spores can be distributed throughout the hive. Because spore germination is critical for AFB establishment, we analyzed the requirements for P. larvae spore germination in vitro. We found that P. larvae spores germinated only in response to l-tyrosine plus uric acid under physiologic pH and temperature conditions. This suggests that the simultaneous presence of these signals is necessary for spore germination in vivo. Furthermore, the germination profiles of environmentally derived spores were identical to those of spores from a biochemically typed strain. Because l-tyrosine and uric acid are the only required germinants in vitro, we screened amino acid and purine analogs for their ability to act as antagonists of P. larvae spore germination. Indole and phenol, the side chains of tyrosine and tryptophan, strongly inhibited P. larvae spore germination. Methylation of the N-1 (but not the C-3) position of indole eliminated its ability to inhibit germination. Identification of the activators and inhibitors of P. larvae spore germination provides a basis for developing new tools to control AFB. PMID:23264573

  20. [Germination strategy and ecological adaptability of Eragrostis pilosa].

    PubMed

    Li, Xuehua; Li, Xiaola; Jiang, Deming; Liu, Zhimin

    2006-04-01

    The study on the germination strategy of Eragrostis pilosa under different storage and environmental conditions showed that freshly collected E. pilosa seeds had a stronger innate dormancy. Chilling and dry storage for 4 months had no obvious effect on releasing from dormancy, while longer time storage could facilitate seed maturation. The seeds could germinate either in light or in darkness, and stronger light was in favor of germination. The optimal temperature for germination was 28 degrees C, while higher or lower temperature could result in the decrease of germination. The germination percentage of seeds under changed temperature (16 to 28 degrees C) was higher than that under constant temperature (28 degrees C), but with no significant difference. The critical amount of rain for seed germination was about 10 mm, and the germination percentage and duration all increased with increasing rainfall. E. pilosa had two germination strategies, i. e., quick germination and dormancy for more than one year. Based on the seed morphological characters and germination strategies, it could be concluded that E. pilosa had a persistent soil seed bank. PMID:16836087

  1. BURSTING POLLEN is required to organize the pollen germination plaque and pollen tube tip in Arabidopsis thaliana.

    PubMed

    Hoedemaekers, Karin; Derksen, Jan; Hoogstrate, Suzanne W; Wolters-Arts, Mieke; Oh, Sung-Aeong; Twell, David; Mariani, Celestina; Rieu, Ivo

    2015-04-01

    Pollen germination may occur via the so-called germination pores or directly through the pollen wall at the site of contact with the stigma. In this study, we addressed what processes take place during pollen hydration (i.e. before tube emergence), in a species with extra-poral pollen germination, Arabidopsis thaliana. A T-DNA mutant population was screened by segregation distortion analysis. Histological and electron microscopy techniques were applied to examine the wild-type and mutant phenotypes. Within 1 h of the start of pollen hydration, an intine-like structure consisting of cellulose, callose and at least partly de-esterified pectin was formed at the pollen wall. Subsequently, this 'germination plaque' gradually extended and opened up to provide passage for the cytoplasm into the emerging pollen tube. BURSTING POLLEN (BUP) was identified as a gene essential for the correct organization of this plaque and the tip of the pollen tube. BUP encodes a novel Golgi-located glycosyltransferase related to the glycosyltransferase 4 (GT4) subfamily which is conserved throughout the plant kingdom. Extra-poral pollen germination involves the development of a germination plaque and BUP defines the correct plastic-elastic properties of this plaque and the pollen tube tip by affecting pectin synthesis or delivery. PMID:25442716

  2. Enhancing gamma-aminobutyric acid content in germinated brown rice by repeated treatment of soaking and incubation.

    PubMed

    Thitinunsomboon, Somboon; Keeratipibul, Suwimon; Boonsiriwit, Athip

    2013-02-01

    Gamma-aminobutyric acid (GABA), commonly produced by germination of brown rice grain, is a free amino acid which could help relieving or preventing non-communicable diseases in human. Several research works have been conducted on GABA production from germinated brown rice. However, the yielded GABA (10.1-69.2 mg/100 g germinated brown rice) was comparatively low; thus the amount was insufficient to be used as active ingredients in functional foods. The objective of this study was to explore alternative methods in order to gain higher yield of GABA. A new process of repeated soaking (in tap water at 35 °C, 3 h) and incubation (at 37 °C, 21 h) during germination was developed. The amount of GABA produced was highest at 116.88 ± 9.24 mg/100 g germinated brown rice (dry basis). However, an unpleasant odour was generated by some microorganisms during long germination. Lactic acid was applied at soaking step to overcome this problem; whereby 0.5% lactic acid solution (vol./vol.) could effectively control the microorganisms without impairing GABA producing ability and sensory qualities. PMID:23345323

  3. Differential activity of Striga hermonthica seed germination stimulants and Gigaspora rosea hyphal branching factors in rice and their contribution to underground communication.

    PubMed

    Cardoso, Catarina; Charnikhova, Tatsiana; Jamil, Muhammad; Delaux, Pierre-Marc; Verstappen, Francel; Amini, Maryam; Lauressergues, Dominique; Ruyter-Spira, Carolien; Bouwmeester, Harro

    2014-01-01

    Strigolactones (SLs) trigger germination of parasitic plant seeds and hyphal branching of symbiotic arbuscular mycorrhizal (AM) fungi. There is extensive structural variation in SLs and plants usually produce blends of different SLs. The structural variation among natural SLs has been shown to impact their biological activity as hyphal branching and parasitic plant seed germination stimulants. In this study, rice root exudates were fractioned by HPLC. The resulting fractions were analyzed by MRM-LC-MS to investigate the presence of SLs and tested using bioassays to assess their Striga hermonthica seed germination and Gigaspora rosea hyphal branching stimulatory activities. A substantial number of active fractions were revealed often with very different effect on seed germination and hyphal branching. Fractions containing (-)-orobanchol and ent-2'-epi-5-deoxystrigol contributed little to the induction of S. hermonthica seed germination but strongly stimulated AM fungal hyphal branching. Three SLs in one fraction, putative methoxy-5-deoxystrigol isomers, had moderate seed germination and hyphal branching inducing activity. Two fractions contained strong germination stimulants but displayed only modest hyphal branching activity. We provide evidence that these stimulants are likely SLs although no SL-representative masses could be detected using MRM-LC-MS. Our results show that seed germination and hyphal branching are induced to very different extents by the various SLs (or other stimulants) present in rice root exudates. We propose that the development of rice varieties with different SL composition is a promising strategy to reduce parasitic plant infestation while maintaining symbiosis with AM fungi. PMID:25126953

  4. Seed Germination and Seedling Emergence of Three Annuals Growing on Desert Sand Dunes in China

    PubMed Central

    TOBE, KAZUO; ZHANG, LIPING; OMASA, KENJI

    2005-01-01

    • Background and Aims Information on the initial growth characteristics of annuals found in Chinese deserts is very limited. The aim of this study was to investigate seed germination and interactive effects of irrigation and seed burial depth in sand on seedling emergence and seedling survival in three annuals (Agriophyllum squarrosum, Bassia dasyphylla and Aristida adscensionis) commonly growing on sand dunes in these regions. • Methods Effects of temperature, light and polyethylene glycol-6000 on seed germination were examined by irrigating seeds sown on filter paper in Petri dishes. Seedling emergence was examined for seeds sown on the surface of, or at different depths (5, 10, 20, 30, 40 and 50 mm) in, sand-filled pots, which were irrigated under different regimes. For seeds buried at a depth of 50 mm, seed viability was examined after irrigation of the pots. • Key Results Seeds of three species germinated at most temperatures recorded between spring and autumn in their native habitats. No seed dormancy was found in any species. For all three species, seedling emergence was most favoured when seeds were buried at a depth of 10 mm. When seeds sown on the sand surface were irrigated, seed germination was considerably suppressed due to water deficiency, but many seeds remained viable. For A. squarrosum and B. dasyphylla, many seeds that were deeply buried and irrigated remained ungerminated but viable, while for A. adscensionis deeply buried seeds germinated, but the seedlings did not emerge due to unfavourable seedling growth in deep sand. • Conclusions Precipitation is the most crucial factor in determining the seasonal emergence of seedlings of the three tested species in the field. The vertical distribution of seeds in sand determines the proportion of seeds that germinate after precipitation and acts to maintain seed banks over multiple years. PMID:15644383

  5. Phytotoxicity of nanoparticles: inhibition of seed germination and root growth.

    PubMed

    Lin, Daohui; Xing, Baoshan

    2007-11-01

    Plants need to be included to develop a comprehensive toxicity profile for nanoparticles. Effects of five types of nanoparticles (multi-walled carbon nanotube, aluminum, alumina, zinc, and zinc oxide) on seed germination and root growth of six higher plant species (radish, rape, ryegrass, lettuce, corn, and cucumber) were investigated. Seed germination was not affected except for the inhibition of nanoscale zinc (nano-Zn) on ryegrass and zinc oxide (nano-ZnO) on corn at 2000 mg/L. Inhibition on root growth varied greatly among nanoparticles and plants. Suspensions of 2000 mg/L nano-Zn or nano-ZnO practically terminated root elongation of the tested plant species. Fifty percent inhibitory concentrations (IC50) of nano-Zn and nano-ZnO were estimated to be near 50mg/L for radish, and about 20mg/L for rape and ryegrass. The inhibition occurred during the seed incubation process rather than seed soaking stage. These results are significant in terms of use and disposal of engineered nanoparticles. PMID:17374428

  6. Seed viability and germination success of Acacia tortilis along land-use and aridity gradients in the Eastern Sahara.

    PubMed

    Andersen, Gidske Leknæs; Krzywinski, Knut; Gjessing, Håkon K; Pierce, Richard Holton

    2016-01-01

    Our study focuses on the keystone species Acacia tortilis and is the first to investigate the effect of domestic ungulates and aridity on seed viability and germination over an extensive part of the Eastern Sahara. Bruchids infest its seeds and reduce their viability and germination, but ingestion by ruminant herbivores diminishes infestation levels and enhances/promotes seed viability and germination. The degree of these effects seems to be correlated with animal body mass. Significantly reduced numbers of wild ruminant ungulates have increased the potential importance of domestic animals and pastoral nomadism for the functionality of arid North African and Middle Eastern ecosystems. We sampled seeds (16,543) from A. tortilis in eight areas in three regions with different aridity and land use. We tested the effect of geography and sampling context on seed infestation using random effects logistic regressions. We did a randomized and balanced germination experiment including 1193 seeds, treated with different manure. Germination time and rates across geography, sampling context, and infestation status were analyzed using time-to-event analyses, Kaplan-Meier curves and proportional hazards Cox regressions. Bruchid infestation is very high (80%), and the effects of context are significant. Neither partial infestation nor adding manure had a positive effect on germination. There is a strong indication that intact, uningested seeds from acacia populations in the extremely arid Western Desert germinate more slowly and have a higher fraction of hard seeds than in the Eastern Desert and the Red Sea Hills. For ingested seeds in the pastoralist areas we find that intact seeds from goat dung germinate significantly better than those from camel dung. This is contrary to the expected body-mass effect. There is no effect of site or variation in tribal management. PMID:26811790

  7. [Effects of simulated acid rain on seed germination and seedling growth of different type corn Zea mays].

    PubMed

    Zhang, Hai-Yan

    2013-06-01

    Taking normal corn, waxy corn, pop corn, and sweet corn as test materials, this paper studied their seed germination and seedling growth under effects of simulated acid rain (pH 6.0, 5.0, 4.0, 3.0, 2.0, and 1.0). Simulated acid rain at pH 2.0-5.0 had no significant effects on the seed germination and seedling growth, but at pH 1.0, the germination rate of normal corn, waxy corn, pop corn, and sweet corn was 91.3%, 68.7%, 27.5%, and 11.7%, respectively. As compared with those at pH 6.0 (CK), the germination rate, germination index, vigor index, germination velocity, shoot height, root length, shoot and root dry mass, and the transformation rate of stored substances at pH 1.0 had significant decrease, and the average germination time extended apparently. At pH 1.0, the effects of acid rain were greater at seedling growth stage than at germination stage, and greater on underground part than on aboveground part. Due to the differences in gene type, normal corn and waxy corn had the strongest capability against acid rain, followed by pop corn, and sweet corn. It was suggested that corn could be categorized as an acid rain-tolerant crop, the injury threshold value of acid rain was likely between pH 1.0 and pH 2.0, and normal corn and waxy corn would be prioritized for planting in acid rain-stricken area. PMID:24066549

  8. Role of charred wood, heat-shock, and light in germination of postfire phrygana species from the Eastern Mediterranean Basin

    USGS Publications Warehouse

    Keeley, J.E.; Baer-Keeley, M.

    1999-01-01

    Seeds of 22 species collected from recently burned phrygana were tested for their response to fire-type cues of charred wood and heat-shock. All Cistus species were stimulated by brief heat-shock, as shown in previous studies; however, none responded to charred wood. Only one of the 22 species was stimulated by charred wood, and only in dark-inhibited seeds, and this response did not occur in the light. The lack of charred-wood-induced germination is in contrast to the substantial proportion of species with this germination response reported for mediterranean-type vegetation in California, the Cape region of South Africa, and Western Australia. Phrygana has many species with heat-shock-stimulated germination, primarily in the Fabaceae and Cistaceae. This germination cue is widespread in these two families, thus, the presence of heat-shock-stimulated germination is a result of homologous, rather than covergent, adaptations in mediterranean-climate ecosystems. Germination response to light was not randomly distributed with respect to fire-type response. Heat-shock-stimulated species were almost uniformly light neutral, in contrast to more opportunistic colonizing species with non-refractory seeds, in which half of the species responded positively or negatively to light.

  9. Oxidative signaling in seed germination and dormancy

    PubMed Central

    El-Maarouf-Bouteau, Hayat

    2008-01-01

    Reactive Oxygen Species (ROS) play a key role in various events of seed life. In orthodox seeds, ROS are produced from embryogenesis to germination, i.e., in metabolically active cells, but also in quiescent dry tissues during after ripening and storage, owing various mechanisms depending on the seed moisture content. Although ROS have been up to now widely considered as detrimental to seeds, recent advances in plant physiology signaling pathways has lead to reconsider their role. ROS accumulation can therefore be also beneficial for seed germination and seedling growth by regulating cellular growth, ensuring a protection against pathogens or controlling the cell redox status. ROS probably also act as a positive signal in seed dormancy release. They interact with abscisic acid and gibberellins transduction pathway and are likely to control numerous transcription factors and properties of specific protein through their carbonylation. PMID:19513212

  10. Effect of Pb, Cd, Hg, As, and Cr on germination and root growth of Sinapis alba seeds

    SciTech Connect

    Fargasova, A. )

    1994-03-01

    Heavy metals have been widely recognized as highly toxic and dangerous. Plants, algae and bacteria respond to heavy metal toxicity by inducing different enzymes, creating ion influx/efflux for ionic balance and synthesizing small peptides. These peptides bind metal ions and reduce toxicity. Metals come from the natural weathering processes of the earth's crust, industrial discharge, pest or disease control agents applied to plants, urban run-off, mining, soil erosion, sewage effluents, air pollution fallout and other sources. Plants can be affected directly by air pollutants, as well as indirectly through the contamination of soil and water. At the same time, plant is a member of the food chain and may create a risk for man and animals through contamination of food supplies. In recent years a considerable progress has been made in the assay of trace elements in environmental plant samples. For higher plants, the accumulation of metals, especially cadmium, was tested when plants grew on sewage sludge-amended soils or in soils of cadmium residues from phosphate fertilizers. No reports were accessible to us on the direct effect of tested metals (Pb, Hg, Cr, As, Cd) on seed germination and root growth. The paucity of literature initiated our present work. In this study, an attempt has been made to investigate the acute toxicity of five metals (Cr[sup 6+], Cd[sup 2+], Hg[sup 2+], Pb[sup 2+], As[sup 5+]) which are widely spread in the environment and are widely recognized as highly toxic and dangerous. As the testing subject, mustard seeds (Sinapis alba) were used and their germination and root growth were observed. 12 refs., 1 tab.

  11. Microbe-Mediated Germination of Ascospores of Monosporascus cannonballus.

    PubMed

    Stanghellini, M E; Kim, D H; Waugh, M

    2000-03-01

    ABSTRACT Ascospores of Monosporascus cannonballus germinated readily in the rhizosphere of cantaloupe plants growing in field soil. However, little or no germination occurred in the rhizosphere of melon plants growing in field soil that was autoclaved prior to infestation with ascospores. The latter data suggested that root exudates alone do not stimulate ascospore germination and that the soil microflora may be involved in the induction of ascospore germination. Amending field soil with streptomycin (which inhibits gram-negative microorganisms) did not suppress ascospore germination in the rhizosphere of cantaloupe plants. However, amending the soil with penicillin (which inhibits gram-positive microorganisms) did suppress ascospore germination. Pentachloronitrobenzene (PCNB), which inhibits the gram-positive actinomycetes but does not inhibit gram-positive or gram-negative bacteria, also suppressed ascospore germination. These results suggest that actinomycetes, either directly or indirectly, are involved in the induction of ascospore germination in field soil in the presence of exudates from cantaloupe roots. Optimum germination occurred at temperatures ranging from 25 to 35 degrees C, and data indicate that a high percentage (>/=72%) of the ascospore population within 500 mum of a root are capable of germination and subsequent penetration of cantaloupe roots. PMID:18944615

  12. Germination and seedling vigor in Beta vulgaris

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One former commercial variety, EL-A012206 (ACH185), and the pollen parent for the commercial variety USH20, EL-A015030 (SP7622) were germinated in H2O and 0.3% H2O2. Samples were collected at 0, 3, 6, 12, 18 and 24 hours of treatment for both varieties. RNA was extracted from the tissue and RT-PCR w...

  13. Germination of vegetable seeds exposed to very high pressure

    NASA Astrophysics Data System (ADS)

    Mori, Y.; Yokota, S.; Ono, F.

    2012-07-01

    Effects of high hydrostatic pressure were investigated on vegetable seeds in the GPa range to examine the potentialities of breed improvement by high-pressure processing. Specimens of several seeds of broccoli (Brassica oleracea var. italica), Turnip leaf (Brassica rapa var. perviridis) and Potherb Mustard (Brassica rapa var. nipposinica) were put in a teflon capsule with liquid high pressure medium, fluorinate, and inserted into a pyrophillite cube. By using a cubic anvil press a hydrostatic pressure of 5.5 GP a was applied to these seeds for 15 minutes. After being brought back to ambient pressure, they were seeded on humid soil in a plant pot. Many of these vegetable seeds began to germinate within 6 days after seeded.

  14. Effects of three fire-suppressant foams on the germination and physiological responses of plants.

    PubMed

    Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

    2014-10-01

    Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks. PMID:24943813

  15. Effects of Three Fire-Suppressant Foams on the Germination and Physiological Responses of Plants

    NASA Astrophysics Data System (ADS)

    Song, Uhram; Mun, Saeromi; Waldman, Bruce; Lee, Eun Ju

    2014-10-01

    Suppressant foams used to fight forest fires may leave residual effects on surviving biota that managers need to consider prior to using them. We examined how three fire-suppressant foams (FSFs) (Forexpan S, Phos-Chek-WD881, and Silv-ex) affected seed germination and physiological responses of three plant species. Exposure to FSFs, whether in diluted concentrations or those typical in the field, reduced final germination percentages of seeds grown in petri dishes and within growth chambers. However, the FSFs did not cause total germination failure in any treatment. Inhibition of germination increased with longer exposure times, but only to diluted FSF solutions. Unlike in the laboratory experiments, none of the three FSFs affected seedling emergence when tested in field conditions. Further, we found no evidence of long-term phytotoxic effects on antioxidant enzyme activity nor chlorophyll content of the plant saplings. Therefore, although the three FSFs showed evidence of phytotoxicity to plants in laboratory tests, their actual impact on terrestrial ecosystems may be minimal. We suggest that the benefits of using these FSFs to protect plants in threatened forest ecosystems outweigh their minor risks.

  16. In situ investigation of Geobacillus stearothermophilus spore germination and inactivation mechanisms under moderate high pressure.

    PubMed

    Georget, Erika; Kapoor, Shobhna; Winter, Roland; Reineke, Kai; Song, Youye; Callanan, Michael; Ananta, Edwin; Heinz, Volker; Mathys, Alexander

    2014-08-01

    Bacterial spores are a major concern for food safety due to their high resistance to conventional preservation hurdles. Innovative hurdles can trigger bacterial spore germination or inactivate them. In this work, Geobacillus stearothermophilus spore high pressure (HP) germination and inactivation mechanisms were investigated by in situ infrared spectroscopy (FT-IR) and fluorometry. G. stearothermophilus spores' inner membrane (IM) was stained with Laurdan fluorescent dye. Time-dependent FT-IR and fluorescence spectra were recorded in situ under pressure at different temperatures. The Laurdan spectrum is affected by the lipid packing and level of hydration, and provided information on the IM state through the Laurdan generalized polarization. Changes in the -CH2 and -CH3 asymmetric stretching bands, characteristic of lipids, and in the amide I' band region, characteristic of proteins' secondary structure elements, enabled evaluation of the impact of HP on endospores lipid and protein structures. These studies were complemented by ex situ analyses (plate counts and microscopy). The methods applied showed high potential to identify germination mechanisms, particularly associated to the IM. Germination up to 3 log10 was achieved at 200 MPa and 55 °C. A molecular-level understanding of these mechanisms is important for the development and validation of multi-hurdle approaches to achieve commercial sterility. PMID:24750808

  17. 21 CFR 212.60 - What requirements apply to the laboratories where I test components, in-process materials, and...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... I test components, in-process materials, and finished PET drug products? 212.60 Section 212.60 Food... finished PET drug products? (a) Testing procedures. Each laboratory used to conduct testing of components, in-process materials, and finished PET drug products must have and follow written procedures for...

  18. 21 CFR 212.60 - What requirements apply to the laboratories where I test components, in-process materials, and...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...) Materials. The identity, purity, and quality of reagents, solutions, and supplies used in testing procedures... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS... finished PET drug products? (a) Testing procedures. Each laboratory used to conduct testing of...

  19. 21 CFR 212.60 - What requirements apply to the laboratories where I test components, in-process materials, and...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Materials. The identity, purity, and quality of reagents, solutions, and supplies used in testing procedures... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS... finished PET drug products? (a) Testing procedures. Each laboratory used to conduct testing of...

  20. 21 CFR 212.60 - What requirements apply to the laboratories where I test components, in-process materials, and...

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Materials. The identity, purity, and quality of reagents, solutions, and supplies used in testing procedures... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS... finished PET drug products? (a) Testing procedures. Each laboratory used to conduct testing of...

  1. Germination and outgrowth of spores of Bacillus cereus group members: diversity and role of germinant receptors.

    PubMed

    Abee, Tjakko; Groot, Masja Nierop; Tempelaars, Marcel; Zwietering, Marcel; Moezelaar, Roy; van der Voort, Menno

    2011-04-01

    Bacillus cereus is a gram-positive, facultative anaerobic, endospore-forming toxicogenic human pathogen. Endospores are highly specialized, metabolically dormant cell types that are resistant to extreme environmental conditions, including heat, dehydration and other physical stresses. B. cereus can enter a range of environments, and can in its spore form, survive harsh conditions. If these conditions become favorable, spores can germinate and grow out and reach considerable numbers in a range of environments including processed foods. Certainly the last decade, when consumer preferences have shifted to mildly processed food, new opportunities arose for spore-forming spoilage and pathogenic organisms. Only rigorous methods have been shown to be capable of destroying all spores present in food, thus a shift toward e.g., milder heat preservation strategies, may result in low but significant amounts of viable spores in food products. Hence, the need for a mild spore destruction strategy is eminent including control of spore outgrowth. Consequently, there is a large interest in triggering spore germination in foodstuffs, since germinated spores have lost the extreme resistance of dormant spores and are relatively easy to kill. Another option could be to prevent germination so that no dangerous levels can be reached. This contribution will focus on germination and outgrowth characteristics of B. cereus and other members of the B. cereus group, providing an overview of the niches these spore-formers can occupy, the signals that trigger germination, and how B. cereus copes with these wake-up calls in different environments including foods, during food processing and upon interaction with the human host. PMID:21315974

  2. Seed Germination of Gastrodia elata Using Symbiotic Fungi, Mycena osmundicola

    PubMed Central

    Kim, Yong-Il; Chang, Kwang-Joon; Ka, Kang-Hyeon; Hur, Hyeon; Hong, In-Pyo; Shim, Jae-Ouk; Lee, Tae-Soo; Lee, Ji-Yul

    2006-01-01

    The germination rate and longevity of seeds of Gastrodia elata Blume have been observed for 48 weeks using Mycena osmundicola strain H-21, one of fungi stimulating seed germination. Storage condition of post-harvest seeds was observed in the different temperature ranges of -30℃, -5℃, 5℃ and 30℃ for 48 weeks. After storage period of 48 weeks, the germination rate of G. elata was 65.7% at 5℃ and 71.6% at -5℃, respectively. Although the germination rate of G. elata was 77.3% for 11 weeks at 25℃, the germination rate had been decreased gradually to 49.3% at 13 weeks, 0.3% at 23 weeks and then 0% at 25 weeks. The germination rate was reached to the level of 10% for 2 weeks at -30℃ and then decreased to 0%. PMID:24039475

  3. Up in smoke: I. Smoke-derived germination cues for postfire annual,Nicotiana attenuata torr. Ex. Watson.

    PubMed

    Baldwin, I T; Staszak-Kozinski, L; Davidson, R

    1994-09-01

    Some postfire annuals with dormant seeds use heat or chemical cues from charred wood to synchronize their germination with the postfire environment. We report that wood smoke and polar extracts of wood smoke, but not the ash of burned wood, contain potent cue(s) that stimulate germination in the postfire annual plant,Nicotiana attenuata. We examined the responses of seeds from six populations of plants from southwest Utah to extracts of smoke and found the proportion of viable seeds that germinated in the presence of smoke cues to vary between populations but to be consistent between generations. With the most dormant genotypes, we examine three mechanisms by which smoke-derived chemical cues may stimulate germination (chemical scarification of the seed coat and nutritive- and signal-mediated stimulation of germination) and report that the response is consistent with the signal-mediated mechanism. The germination cue(s) found in smoke are produced by the burning of hay, hardwood branches, leaves, and, to a lesser degree, cellulose. Moreover, the cues are found in the common food condiment, "liquid smoke," and we find no significant differences between brands. With a bioassay-driven fractionation of liquid smoke, we identified 71 compounds in active fractions by GC-MS and AA spectrometry. However, when these compounds were tested in pure form or in combinations that mimicked the composition of active fractions over a range of concentrations, they failed to stimulate germination to the same degree that smoke fractions did. Moreover, enzymatic oxidation of some of these compounds also failed to stimulate germination. In addition, we tested 43 additional compounds also reported from smoke, 85 compounds that were structurally similar to those reported from smoke and 34 compounds reported to influence germination in other species. Of the 233 compounds tested, 16 proved to inhibit germination at the concentrations tested, and none reproduced the activity of wood smoke. By

  4. Allium cepa chromosome aberration and micronucleus tests applied to study genotoxicity of extracts from pesticide-treated vegetables and grapes.

    PubMed

    Feretti, D; Zerbini, I; Zani, C; Ceretti, E; Moretti, M; Monarca, S

    2007-06-01

    The Allium cepa assay is an efficient test for chemical screening and in situ monitoring for genotoxicity of environmental contaminants. The test has been used widely to study genotoxicity of many pesticides revealing that these compounds can induce chromosomal aberrations in root meristems of A. cepa. Pesticide residues can be present in fruit and vegetables and represent a risk for human health. The mutagenic and carcinogenic action of herbicides, insecticides and fungicides on experimental animals is well known. Several studies have shown that chronic exposure to low levels of pesticides can cause birth defects and that prenatal exposure is associated with carcinogenicity. This study evaluated the potential application of plant genotoxicity tests for monitoring mutagens in edible vegetables. The presence of pesticides and genotoxic compounds extracted from 21 treated vegetables and eight types of grapes sampled from several markets in Campania, a region in Southern Italy, was monitored concurrently. The extracts were analysed for pesticides by gas chromatography and high-performance liquid chromatography, and for genotoxicity using two plant tests: the micronucleus test and the chromosomal aberration test in A. cepa roots. Thirty-three pesticides were detected, some of which are not approved. Genotoxicity was found in some of the vegetables and grapes tested. Allium cepa tests proved to be sensitive in monitoring genotoxicity in food extracts. The micronucleus test in interphase cells gave a much higher mutagenicity than the chromosomal aberration test in anaphase-telophase cells. PMID:17487597

  5. Ecophysiology of seed germination of wild Dahlia coccinea (Asteraceae) in a spatially heterogeneous fire-prone habitat

    NASA Astrophysics Data System (ADS)

    Vivar-Evans, Susana; Barradas, Víctor L.; Sánchez-Coronado, María E.; Gamboa de Buen, Alicia; Orozco-Segovia, Alma

    2006-03-01

    Dahlia coccinea grows on fire-prone xerophilous shrubland, on a lava field located in Mexico City. Two kinds of experiments were performed to test the role of fire and environmental heterogeneity on germination. The first experiment tested the effect of environmental conditions (constant and alternating temperatures, cold stratification and light). The second one tested the effects of fire and high temperatures (dry and moist heat) on germination. Seeds of Dahlia were indifferent to light. The seeds showed physiological dormancy, which was lost by after-ripening or by gibberellins. During simulated fires, dry seeds tolerated high temperatures of short duration and also withstood prolonged exposure to 60 °C. Dry heat treatment reduced the mechanical restriction for embryo growth in dormant seeds. Ash and prolonged exposure to moist heat inhibited germination. Exogenous gibberellins reversed the deleterious effects of prolonged exposure to moist heat. The effect of cold stratification was related to the seeds' physiological stage and to light conditions; stratification in the dark reduced germination. Seeds of D. coccinea could tolerate, evade, or be slightly favored by the effects of low intensity fires occurring in their habitat. Seed responses to treatments suggest that the spatially heterogeneous lava field could provide a wide variety of micro-sites where physiological dormancy could be broken and during fires seeds could maintain their viability and subsequently germinate and/or develop a seed bank.

  6. Seed germination characteristics of Chrysothamnus nauseosus ssp. viridulus (Astereae, Asteraceae)

    SciTech Connect

    Khan, M.A.; Sankhla, N.; Weber, D.J.; McArthur, E.D.

    1987-04-30

    Rubber rabbitbrush (Chrysothamnus nauseosus (Pallas) Britt. ssp. viridulus) may prove to be a source of high-quality cis-isoprene rubber, but its establishment is limited by a lack of information on seed germination. Consequently, seeds were germinated at alternating temperatures (5-15, 5-25, 15-25, and 20-30 C) in light and dark as well as constant temperatures (15-40 C with 5-C increments) to determine temperature response. Seeds were also germinated in solutions of polyethylene glycol 6000, salinity regimes at all the above-mentioned temperatures to determine salinity and temperature interaction. The hormones GA/sub 3/ and kinetin were used to study their effect on overcoming salt- and temperature-induced germination inhibition. Seeds of C. nauseosus ssp. viridulus were very sensitive to low temperature. Best germination was achieved at 25 and 30 C, but these seeds also germinated at a higher temperature (35 C). The seeds of rabbit brush germinated at both constant and alternating temperatures. Light appears to play little or no role in controlling germination of the seeds of rubber rabbitbrush. However, seeds of rabbitbrush were sensitive to salinity, and seed germination was progressively inhibited by increase in salt concentration, although a few seeds still germinated at the highest saline level. Progressively higher concentrations of polyethylene glycol also progressively inhibited germination. Suppression of seed germination induced by high salt concentrations and high temperatures can be partially alleviated by the application of either GA/sub 3/ or kinetin. 34 references, 5 figures, 3 tables.

  7. Protein turnover in Azotobacter vinelandii during encystment and germination.

    PubMed

    Ruppen, M E; Garner, G; Sadoff, H L

    1983-12-01

    Protein turnover occurs during differentiation of Azotobacter vinelandii 12837 to the extent of 50% during encystment and 7% during germination. The addition of rifampin at the initiation of encystment prevents encystment and inhibits turnover. In germinating cysts, protein turnover is essential owing to an apparent lack of certain amino acid biosynthetic enzymes. The capacity to synthesize sulfur-containing amino acids from inorganic precursors is regained about halfway through the germination process. PMID:6643391

  8. Development of a superconductor magnetic suspension and balance prototype facility for studying the feasibility of applying this technique to large scale aerodynamic testing

    NASA Technical Reports Server (NTRS)

    Zapata, R. N.; Humphris, R. R.; Henderson, K. C.

    1975-01-01

    The basic research and development work towards proving the feasibility of operating an all-superconductor magnetic suspension and balance device for aerodynamic testing is presented. The feasibility of applying a quasi-six-degree-of freedom free support technique to dynamic stability research was studied along with the design concepts and parameters for applying magnetic suspension techniques to large-scale aerodynamic facilities. A prototype aerodynamic test facility was implemented. Relevant aspects of the development of the prototype facility are described in three sections: (1) design characteristics; (2) operational characteristics; and (3) scaling to larger facilities.

  9. Effect of sonic stimulation on Bacillus endospore germination.

    PubMed

    Liu, Si Li; Wu, Wen Jie; Yung, Pun To

    2016-01-01

    This study investigates the effect of sonic stimulation on Bacillus endospore germination. Germinating endospores in a microtiter plate were exposed to audible sound wave generated by an array of piezoelectric transducers. In situ germination kinetics was measured by terbium-dipicolinate fluorescence assay, optical density measurement and phase contrast microscopy. Fluorescence results revealed that sonic stimulation (5 kHz at 90 dB) promoted the germination speed by 43.7% ± 11.3% and final germination level by 61.7% ± 11.9% of Bacillus atrophaeus. This acoustic energy absorbed by endospores is postulated to change membrane permeability and increase enzyme activities; thereby, expediting the germination process. This also raises the likelihood of dormant endospores undergoing germination because of a rapid release of unidentified chemical mediators for quorum sensing. On the other hand, acoustic effect was not observed in B. subtilis endospores. This may be attributed to the different spore aspect ratio, 1.43 ± 0.05 for B. atrophaeus and 2.02 ± 0.08 for B. subtilis, which results in a difference in specific absorption rates towards audible sound waves. Our results demonstrate the modulation of endospore germination by an external field to shed light on germination mechanism and cell-wave interaction. PMID:26607285

  10. An analysis of B cell selection mechanisms in germinal centers.

    PubMed

    Meyer-Hermann, Michael E; Maini, Philip K; Iber, Dagmar

    2006-09-01

    Affinity maturation of antibodies during immune responses is achieved by multiple rounds of somatic hypermutation and subsequent preferential selection of those B cells that express B cell receptors with improved binding characteristics for the antigen. The mechanism underlying B cell selection has not yet been defined. By employing an agent-based model, we show that for physiologically reasonable parameter values affinity maturation can be driven by competition for neither binding sites nor antigen--even in the presence of competing secreted antibodies. Within the tested mechanisms, only clonal competition for T cell help or a refractory time for the interaction of centrocytes with follicular dendritic cells is found to enable affinity maturation while generating the experimentally observed germinal centre characteristics and tolerating large variations in the initial antigen density. PMID:16707510

  11. Reduced germination of Orobanche cumana seeds in the presence of Arbuscular Mycorrhizal fungi or their exudates.

    PubMed

    Louarn, Johann; Carbonne, Francis; Delavault, Philippe; Bécard, Guillaume; Rochange, Soizic

    2012-01-01

    Broomrapes (Orobanche and Phelipanche spp) are parasitic plants responsible for important crop losses, and efficient procedures to control these pests are scarce. Biological control is one of the possible strategies to tackle these pests. Arbuscular Mycorrhizal (AM) fungi are widespread soil microorganisms that live symbiotically with the roots of most plant species, and they have already been tested on sorghum for their ability to reduce infestation by witchweeds, another kind of parasitic plants. In this work AM fungi were evaluated as potential biocontrol agents against Orobanche cumana, a broomrape species that specifically attacks sunflower. When inoculated simultaneously with O. cumana seeds, AM fungi could offer a moderate level of protection against the broomrape. Interestingly, this protection did not only rely on a reduced production of parasitic seed germination stimulants, as was proposed in previous studies. Rather, mycorrhizal root exudates had a negative impact on the germination of O. cumana induced by germination stimulants. A similar effect could be obtained with AM spore exudates, establishing the fungal origin of at least part of the active compounds. Together, our results demonstrate that AM fungi themselves can lead to a reduced rate of parasitic seed germination, in addition to possible effects mediated by the mycorrhizal plant. Combined with the other benefits of AM symbiosis, these effects make AM fungi an attractive option for biological control of O. cumana. PMID:23145139

  12. Expression of genes related to tolerance to low temperature for maize seed germination.

    PubMed

    Silva-Neta, I C; Pinho, E V; Veiga, A D; Pìnho, R G; Guimarães, R M; Caixeta, F; Santos, H O; Marques, T L

    2015-01-01

    The aim of this study was to characterize maize lines tolerant to cold temperatures during the germination process. Seeds from lines with different levels of tolerance to low temperatures were used; 3 lines were classified as tolerant and 3 as susceptible to low germination temperatures. A field was set up to multiply seeds from selected lines. After the seeds were harvested and classified, we conducted physiological tests and analyzed fatty acid content of palmitic, stearic, oleic, linoleic, linolenic, and eicosenoic acids. In proteomic analysis, the expression of heat-resistant proteins, including catalase, peroxidase, esterase, superoxide dismutase, and α-amylase, were evaluated. Transcript analysis was used to measure the expression of the genes AOX1, AOX2, ZmMPK-17, and ZmAN-13. The material showing the highest susceptibility to low germination temperatures contained high saturated fatty acid content. Expression of α-amylase in seeds soaked for 72 h at a temperature of 10°C was lower than expression of α-amylase when soaked at 25°C for the same amount of time. We observed variation in the expression of heat-resistant proteins in seeds of the lines evaluated. The genes AOX and Zm-AN13 were promising for use in identifying maize materials that are tolerant to low germination temperatures. PMID:25867416

  13. Effects of cyanobacteria producing microcystins on seed germination and seedling growth of several agricultural plants.

    PubMed

    Saqrane, Sana; El Ghazali, Issam; Oudra, Brahim; Bouarab, L; Vasconcelos, Vitor

    2008-06-01

    The effects of cyanobacteria aqueous extracts containing Microcystin-LR (MC-LR) on the seed germination and growth of Pisum sativum, Lens esculenta, Zea mays and Triticum durum were investigated. Experiments were carried out on a range of doses of the extract (equivalent to 0, 1.6, 2.9, 5.8, 8.7 and 11.6 mu g MC-LR/mL). The results confirm that these plants were sensitive to cell-free extracts of a toxic Microcystis and that germination inhibition was dose dependent. One-way analysis of variance (ANOVA) showed that P. sativum is the most sensitive tested species with a 97% germination rate reduction and L. esculenta was the most resistant. At the 8th day, the exposure to the microcystins (MC) resulted in a significant decrease of plant epicotyls length, roots length and a net inhibition of lateral root formation. It is concluded that MC could affect also terrestrial plants seedling germination and growth. Therefore, the use of water for irrigation contaminated by MC could exert negative biochemical effects on seed and plant metabolism which might influence the agricultural crops. PMID:18576226

  14. Applying Multidimensional Item Response Theory Models in Validating Test Dimensionality: An Example of K-12 Large-Scale Science Assessment

    ERIC Educational Resources Information Center

    Li, Ying; Jiao, Hong; Lissitz, Robert W.

    2012-01-01

    This study investigated the application of multidimensional item response theory (IRT) models to validate test structure and dimensionality. Multiple content areas or domains within a single subject often exist in large-scale achievement tests. Such areas or domains may cause multidimensionality or local item dependence, which both violate the…

  15. Seed germination ecology of Echinochloa glabrescens and its implication for management in rice (Oryza sativa L.).

    PubMed

    Opeña, Jhoana L; Chauhan, Bhagirath S; Baltazar, Aurora M

    2014-01-01

    Echinochloa glabrescens is a C4 grass weed that is very competitive with rice when left uncontrolled. The competitive ability of weeds is intensified in direct-seeded rice production systems. A better understanding is needed of factors affecting weed seed germination, which can be used as a component of integrated weed management in direct-seeded rice. This study was conducted to determine the effects of temperature, light, salt and osmotic stress, burial depth, crop residue, time and depth of flooding, and herbicide application on the emergence, survival, and growth of two populations [Nueva Ecija (NE) and Los Baños (IR)] of E. glabrescens. Seeds from both populations germinated at all temperatures. The NE population had a higher germination rate (88%) from light stimulation than did the IR population (34%). The salt concentration and osmotic potential required to inhibit 50% of germination were 313 mM and -0.24 MPa, respectively, for the NE population and 254 mM and -0.33 MPa, respectively, for the IR population. Emergence in the NE population was totally inhibited at 4-cm burial depth in the soil, whereas that of the IR population was inhibited at 8 cm. Compared with zero residue, the addition of 5 t ha(-1) of rice residue reduced emergence in the NE and IR populations by 38% and 9%, respectively. Early flooding (within 2 days after sowing) at 2-cm depth reduced shoot growth by 50% compared with non-flooded conditions. Pretilachlor applied at 0.075 kg ai ha(-1) followed by shallow flooding (2-cm depth) reduced seedling emergence by 94-96% compared with the nontreated flooded treatment. Application of postemergence herbicides at 4-leaf stage provided 85-100% control in both populations. Results suggest that integration of different strategies may enable sustainable management of this weed and of weeds with similar germination responses. PMID:24642568

  16. Seed Germination Ecology of Echinochloa glabrescens and Its Implication for Management in Rice (Oryza sativa L.)

    PubMed Central

    Opeña, Jhoana L.; Chauhan, Bhagirath S.; Baltazar, Aurora M.

    2014-01-01

    Echinochloa glabrescens is a C4 grass weed that is very competitive with rice when left uncontrolled. The competitive ability of weeds is intensified in direct-seeded rice production systems. A better understanding is needed of factors affecting weed seed germination, which can be used as a component of integrated weed management in direct-seeded rice. This study was conducted to determine the effects of temperature, light, salt and osmotic stress, burial depth, crop residue, time and depth of flooding, and herbicide application on the emergence, survival, and growth of two populations [Nueva Ecija (NE) and Los Baños (IR)] of E. glabrescens. Seeds from both populations germinated at all temperatures. The NE population had a higher germination rate (88%) from light stimulation than did the IR population (34%). The salt concentration and osmotic potential required to inhibit 50% of germination were 313 mM and −0.24 MPa, respectively, for the NE population and 254 mM and −0.33 MPa, respectively, for the IR population. Emergence in the NE population was totally inhibited at 4-cm burial depth in the soil, whereas that of the IR population was inhibited at 8 cm. Compared with zero residue, the addition of 5 t ha−1 of rice residue reduced emergence in the NE and IR populations by 38% and 9%, respectively. Early flooding (within 2 days after sowing) at 2-cm depth reduced shoot growth by 50% compared with non-flooded conditions. Pretilachlor applied at 0.075 kg ai ha−1 followed by shallow flooding (2-cm depth) reduced seedling emergence by 94−96% compared with the nontreated flooded treatment. Application of postemergence herbicides at 4-leaf stage provided 85−100% control in both populations. Results suggest that integration of different strategies may enable sustainable management of this weed and of weeds with similar germination responses. PMID:24642568

  17. 40 CFR 86.1901 - What testing requirements apply to my engines that have gone into service?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... listed in § 86.1910(d) other than PM beginning in calendar year 2005 and you must measure PM emissions beginning in calendar year 2007. See § 86.1930 for special provisions that may apply to manufacturers in the early years of this program. (b) We may void your certificate of conformity for an engine family if...

  18. 40 CFR 86.1901 - What testing requirements apply to my engines that have gone into service?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... listed in § 86.1910(d) other than PM beginning in calendar year 2005 and you must measure PM emissions beginning in calendar year 2006. See §§ 86.1930 and 86.1935 for special provisions that may apply to manufacturers in the early years of this program. (b) We may void your certificate of conformity for an...

  19. Magnetic Test Performance Capabilities at the Goddard Space Flight Center as Applied to the Global Geospace Science Initiative

    NASA Technical Reports Server (NTRS)

    Mitchell, Darryl R.

    1997-01-01

    Goddard Space Flight Center's (GSFC) Spacecraft Magnetic Test Facility (SMTF) is a historic test facility that has set the standard for all subsequent magnetic test facilities. The SMTF was constructed in the early 1960's for the purpose of simulating geomagnetic and interplanetary magnetic fields. Additionally, the facility provides the capability for measuring spacecraft generated magnetic fields as well as calibrating magnetic attitude control systems and science magnetometers. The SMTF was designed for large, spacecraft level tests and is currently the second largest spherical coil system in the world. The SMTF is a three-axis Braunbek system composed of four coils on each of three orthogonal axes. The largest coils are 12.7 meters (41.6 feet) in diameter. The three-axis Braunbek configuration provides a highly uniform cancellation of the geomagnetic field over the central 1.8 meter (6 foot) diameter primary test volume. Cancellation of the local geomagnetic field is to within +/-0.2 nanotesla with a uniformity of up to 0.001% within the 1.8 meter (6 foot) diameter primary test volume. Artificial magnetic field vectors from 0-60,000 nanotesla can be generated along any axis with a 0.1 nanotesla resolution. Oscillating or rotating field vectors can also be produced about any axis with a frequency of up to 100 radians/second. Since becoming fully operational in July of 1967, the SMTF has been the site of numerous spacecraft magnetics tests. Spacecraft tested at the SMTF include: the Solar Maximum Mission (SMM), Magsat, LANDSAT-D, the Fast Aurora] Snapshot (FAST) Explorer and the Sub-millimeter-Wave-Astronomy Satellite (SWAS) among others. This paper describes the methodology and sequencing used for the Global Geospace Science (GGS) initiative magnetic testing program in the Goddard Space Flight Center's SMTF. The GGS initiative provides an exemplary model of a strict and comprehensive magnetic control program.

  20. Seed germination and root elongation as indicators of exposure of wetland seedlings to metals

    SciTech Connect

    Sutton, H.D.; Stokes, S.L.; Hook, D.D.; Klaine, S.J.

    1995-12-31

    Wetland ecosystems have often been impacted by the addition of hazardous waste materials. Methods are needed to evaluate the effect of these substances on wetland ecosystems and the organisms within them. This study evaluates the response of various wetland plant species to representative contaminants (cadmium, nickel, atrazine, anthracene, and tetrachloroethylene). Species tested include Caphalanthus occidentalis (buttonbush), Saururus cernuus (lizard`s tail), Liquidambar styraciflua (sweetgum), Sparganium americanum (bur-reed), and Fraxinus pennsylvanica (green ash). To the authors` knowledge these species have rarely if ever been used in toxicological assays. The endpoints used are germination and root elongation. Preliminary studies using a petri dish system have shown decreased germination at the highest metal concentration (50mg/L) and decreased root elongation in the higher metal concentrations (10, 25, and 50mg/L). Interference from the carrier was observed in the organic tests. Root elongation studies using the metals are being continued using tubes with various sand and vermiculite mixes into which freshly germinated seeds are placed. Species with the best responses will be tested in the field at the Savannah River Site, SC, and also with fuel oil. Lettuce (Lactuca saliva) and radish (Raphanus sativus) are being tested alongside the wetland species as reference organisms for which tests are well established.

  1. Segregation for salt tolerant germination among progeny of Ames 3051 selected under salt germination conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improved germination of seeds under abiotic stress appears to be one means by which improved stand establishment can be accomplished. Salinity is one such stress that may serve a dual purpose by allowing selection for improved stand establishment as well as obtaining a profitable stand in saline so...

  2. Factors affecting spore germination in algae - review.

    PubMed

    Agrawal, S C

    2009-01-01

    This review surveys whatever little is known on the influence of different environmental factors like light, temperature, nutrients, chemicals (such as plant hormones, vitamins, etc.), pH of the medium, biotic factors (such as algal extracellular substances, algal concentration, bacterial extracellular products, animal grazing and animal extracellular products), water movement, water stress, antibiotics, UV light, X-rays, gamma-rays, and pollution on the spore germination in algae. The work done on the dormancy of algal spores and on the role of vegetative cells in tolerating environmental stress is also incorporated. PMID:19826917

  3. Applying Flammability Limit Probabilities and the Normoxic Upward Limiting Pressure Concept to NASA STD-6001 Test 1

    NASA Technical Reports Server (NTRS)

    Olson, Sandra L.; Beeson, Harold; Fernandez-Pello, A. Carlos

    2014-01-01

    Repeated Test 1 extinction tests near the upward flammability limit are expected to follow a Poisson process trend. This Poisson process trend suggests that rather than define a ULOI and MOC (which requires two limits to be determined), it might be better to define a single upward limit as being where 1/e (where e (approx. equal to 2.7183) is the characteristic time of the normalized Poisson process) of the materials burn, or, rounding, where approximately 1/3 of the samples fail the test (and burn). Recognizing that spacecraft atmospheres will not bound the entire oxygen-pressure parameter space, but actually lie along the normoxic atmosphere control band, we can focus the materials flammability testing along this normoxic band. A Normoxic Upward Limiting Pressure (NULP) is defined that determines the minimum safe total pressure for a material within the constant partial pressure control band. Then, increasing this pressure limit by a factor of safety, we can define the material as being safe to use at the NULP + SF (where SF is on the order of 10 kilopascal, based on existing flammability data). It is recommended that the thickest material to be tested with the current Test 1 igniter should be 3 mm thick (1/8 inches) to avoid the problem of differentiating between an ignition limit and a true flammability limit.

  4. Conserved Transcriptional Regulatory Programs Underlying Rice and Barley Germination

    PubMed Central

    Lin, Li; Tian, Shulan; Kaeppler, Shawn; Liu, Zongrang; An, Yong-Qiang (Charles)

    2014-01-01

    Germination is a biological process important to plant development and agricultural production. Barley and rice diverged 50 million years ago, but share a similar germination process. To gain insight into the conservation of their underlying gene regulatory programs, we compared transcriptomes of barley and rice at start, middle and end points of germination, and revealed that germination regulated barley and rice genes (BRs) diverged significantly in expression patterns and/or protein sequences. However, BRs with higher protein sequence similarity tended to have more conserved expression patterns. We identified and characterized 316 sets of conserved barley and rice genes (cBRs) with high similarity in both protein sequences and expression patterns, and provided a comprehensive depiction of the transcriptional regulatory program conserved in barley and rice germination at gene, pathway and systems levels. The cBRs encoded proteins involved in a variety of biological pathways and had a wide range of expression patterns. The cBRs encoding key regulatory components in signaling pathways often had diverse expression patterns. Early germination up-regulation of cell wall metabolic pathway and peroxidases, and late germination up-regulation of chromatin structure and remodeling pathways were conserved in both barley and rice. Protein sequence and expression pattern of a gene change quickly if it is not subjected to a functional constraint. Preserving germination-regulated expression patterns and protein sequences of those cBRs for 50 million years strongly suggests that the cBRs are functionally significant and equivalent in germination, and contribute to the ancient characteristics of germination preserved in barley and rice. The functional significance and equivalence of the cBR genes predicted here can serve as a foundation to further characterize their biological functions and facilitate bridging rice and barley germination research with greater confidence. PMID

  5. Seed germination of GA-insensitive sleepy1 mutants does not require RGL2 protein disappearance in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed germination is a complex developmental process regulated by phytohormones. The phytohormone abscisic acid (ABA) inhibits seed germination, whereas gibberellin (GA) stimulates seed germination. In tomato and Arabidopsis, GA is clearly required for seed germination. Recent evidence suggests tha...

  6. Effect of different fertilizers on the germination and growth of velvetleaf (Abutilon theohrasti Medic.).

    PubMed

    Nagy, V; Nádasy, E

    2011-01-01

    Velvetleaf (Abutilon theophrasti Medic.) is one of the most important and invasive weed species in Hungary and also in Europe. Its dangerousness derives from its germination biology characteristics and its strong competitive and allelopathic ability. In wide line space crops such as corn, sunflower and soybean it may reduce the yield significantly, According to some authors, this yield reducing ability is lower with bigger nutrient supplies. Our experiment was carried in Keszthely, Hungary (46 degrees 45'35.53"; 17 degrees 14'26.9") at the Institute of Plant Protection, Georgikon Faculty, University of Pannonia in 2009 and 2010. We studied the separate and combined effect of different fertilizers on the germination and growth of velvetleaf in greenhouse pot experiments. The applied fertilizers were Linzer NAC (27% N) in doses of 200 kg N ha(-1) (2,325 g Linzer NAC/pot), Patent Káli (30% K2O) in 100 kg K2O ha(-1) (1,05g Patent Káli/pot) and DC Szuperfoszfát (20.5% P2O5) in 100 kg P2O5 ha(-1) (1,05g DC Szuperfoszfát/pot). Our study was carried out in 1.5-litre pots with Ramman brown-forest soil in four replications, with 25 seeds of velvetleaf per pots. Five velvetleaf plants were removed four and six weeks after planting from the pots and the lenght, the fresh- and the air dried weight and the leaf area of the plants was measured. The data were analyzed by ANOVA. We observed that nitrogen which was applied alone or with other nutrients can reduce the germination and growth of Abutilon with 200kg N ha(-1) doses. Potassium and phosphorus stimulate germination and growth. The biggest stimulating effect was produced by potassium when it was applied alone. PMID:22696961

  7. Early quantitative method for measuring germination in non-green spores of Dryopteris paleacea using an epifluorescence-microscope technique

    NASA Technical Reports Server (NTRS)

    Scheuerlein, R.; Wayne, R.; Roux, S. J.

    1988-01-01

    A method is described to determine germination by blue-light excited red fluorescence in the positively photoblastic spores of Dryopteris paleacea Sw. This fluorescence is due to chlorophyll as evidenced from 1) a fluorescence-emission spectrum in vivo, where a bright fluorescence around 675 nm is obtained only in red light (R)-irradiated spores and 2) in vitro measurements with acetone extracts prepared from homogenized spores. Significant amounts of chlorophyll can be found only in R-treated spores; this chlorophyll exhibits an emission band around 668 nm, when irradiated with 430 nm light at 21 degrees C. Compared to other criteria for germination, such as swelling of the cell, coat splitting, greening, and rhizoid formation, which require longer periods after induction for their expression, chlorophyll fluorescence can be used to quantify germination after two days. This result is confirmed by fluence-response curves for R-induced spore germination; the same relationship between applied R and germination is obtained by the evaluation with the epifluorescence method 2 days after the light treatment as compared with the evaluation with bright-field microscopy 5 days after the inducing R. Using this technique we show for the first time that Ca2+ contributes to the signal-transduction chain in phytochrome-mediated chlorophyll synthesis in spores of Dryopteris paleacea.

  8. Germination and ROS detoxification in bell pepper (Capsicum annuum L.) under NaCl stress and treatment with microalgae extracts.

    PubMed

    Guzmán-Murillo, María A; Ascencio, Felipe; Larrinaga-Mayoral, Juan A

    2013-02-01

    We evaluated the salt tolerance of hybrids of pepper (Capsicum annuum L.) during germination. Treatments were applied at 0, 25, and 50 mM NaCl with preparations of supplemental extracts of the microalgae Dunaliella salina and Phaeodactylum tricornutum to determine the percentage germination rate as well as measured indicators of oxidative stress caused by the salt treatments during seed germination. We found that root growth was favorably influenced by the microalgae leading to increased germination rate. Tissues were analyzed in terms of superoxide radical production, lipid peroxidation, and activity of antioxidant enzymes viz. superoxide dismutase, catalase, and glutathione peroxidase. Our results suggest that application of microalgae extracts significantly reduced (p < 0.05) superoxide radical production, as well as lower lipid peroxidation in comparison to plants without extracts of microalgae. The antioxidant enzymes increased in the presence of microalgae showing a significant difference (p < 0.05). The results suggest differences in oxidative metabolism in response to the magnitude of salt stress and concentrations of microalgae help mitigate salt stress in plants during the germination process. PMID:22234834

  9. Paper-and-Pencil and Web-Based Testing: The Measurement Invariance of the Big Five Personality Tests in Applied Settings

    ERIC Educational Resources Information Center

    Vecchione, Michele; Alessandri, Guido; Barbaranelli, Claudio

    2012-01-01

    This study investigates the measurement equivalence of a five-factor measure of personality across two groups applying for jobs, who completed the same questionnaire using either a paper-and-pencil (n = 429) or a web online answer format (n = 651). The data were collected using the Big Five Questionnaire-2 (BFQ-2; which is a measure of the Five…

  10. Up in smoke: II. Germination ofNicotiana attenuata in response to smoke-derived cues and nutrients in burned and unburned soils.

    PubMed

    Baldwin, I T; Morse, L

    1994-09-01

    Nicotiana attenuata is a native tobacco that is commonly found usually one growing season after fires in the blackbrush, sagebrush and pinyon-juniper forests of the Great Basin desert of North America. This plant also occurs in isolated dry washes and roadsides for many consecutive seasons. Postfire annuals are thought to synchronize their germination from the seed bank with the postfire environment in response to increases in (1) fire-related cues or (2) nutrient supply rates resulting from the mineralization of nutrients by fire, or (3) the removal of allelochemicals produced by the dominant vegetation occupying the sites before the burn or the microbial community associated with the dominant vegetation. We examine the effect of these three changes on the germination ofN. attenuata seed from artificial seed banks made with burned and unburned soil taken in 1993 from under four dominant shrub species (Coleogyne ramosissima, Yucca baccata, Lycium andersonnii, Purshia tridentata) of an area that burned in 1992 and from two dry washes in whichN. attenuata populations have persisted since at least 1988. We utilize our recent discovery that aqueous extracts of wood smoke contain potent germination cue(s) for this species and the established observation that nitrate stimulates germination in manyNicotiana species. In two experiments, we added smoke-derived germination cues and nutrients separately and in combinations to the artificial seed banks, measured germination rates, and inferred the effect of burning by the response of the seed banks to these additions. Germination rates of seed in burned soil were consistently higher than those in unburned soil collected from under all species tested; concentrations of nitrate, P, Mn, and Ca were also higher in burned than unburned soils. Because the addition of more cue and nitrate to burned soil increased germination rates, these soil components may not be at concentrations sufficient to saturate the germination response one

  11. Similarity analysis applied to the design of scaled tests of hydraulic mitigation methods for Tank 241-SY-101

    SciTech Connect

    Liljegren, L.M.

    1993-02-01

    The episodic gas releases from Tank 241-SY-101 (SY-101) pose a potential safety hazard. It is thought that gas releases occur because gases are generated and trapped in layers of settled solids located at the bottom of the tank. This document focuses on issues associated with testing of hydraulic mitigation technologies proposed for SY-101. The basic assumption underlying the concept of hydraulic mitigation is that mobilization or maintained suspension of the solids settled in the bottom of the tank wig prevent gas accumulation. Engineering of hydraulic technologies will require testing to determine the operating parameters required to mobilize the solids and to maintain these solids in suspension. Because full scale testing is extremely expensive (even when possible), scaled tests are needed to assess the merit of the proposed technologies and to provide data for numerical or analytical modeling. This research is conducted to support testing and evaluation of proposed hydraulic mitigation concepts only. The work here is oriented towards determining the jet velocities, nozzle sizes, and other operating parameters required to mobilize the settled solids in SY- 101 and maintain them in suspension.

  12. Effect of Essential Oils on Germination and Growth of Some Pathogenic and Spoilage Spore-Forming Bacteria.

    PubMed

    Voundi, Stève Olugu; Nyegue, Maximilienne; Lazar, Iuliana; Raducanu, Dumitra; Ndoye, Florentine Foe; Marius, Stamate; Etoa, François-Xavier

    2015-06-01

    The use of essential oils as a food preservative has increased due to their capacity to inhibit vegetative growth of some bacteria. However, only limited data are available on their effect on bacterial spores. The aim of the present study was to evaluate the effect of some essential oils on the growth and germination of three Bacillus species and Geobacillus stearothermophilus. Essential oils were chemically analyzed using gas chromatography and gas chromatography coupled to mass spectrometry. The minimal inhibitory and bactericidal concentrations of vegetative growth and spore germination were assessed using the macrodilution method. Germination inhibitory effect of treated spores with essential oils was evaluated on solid medium, while kinetic growth was followed using spectrophotometry in the presence of essential oils. Essential oil from Drypetes gossweileri mainly composed of benzyl isothiocyanate (86.7%) was the most potent, with minimal inhibitory concentrations ranging from 0.0048 to 0.0097 mg/mL on vegetative cells and 0.001 to 0.002 mg/mL on spore germination. Furthermore, essential oil from D. gossweileri reduced 50% of spore germination after treatment at 1.25 mg/mL, and its combination with other oils improved both bacteriostatic and bactericidal activities with additive or synergistic effects. Concerning the other essential oils, the minimal inhibitory concentration ranged from 5 to 0.63 mg/mL on vegetative growth and from 0.75 to 0.09 mg/mL on the germination of spores. Spectrophotometric evaluation showed an inhibitory effect of essential oils on both germination and outgrowth. From these results, it is concluded that some of the essential oils tested might be a valuable tool for bacteriological control in food industries. Therefore, further research regarding their use as food preservatives should be carried out. PMID:25884442

  13. Effects of soil contamination by trace elements on white poplar progeny: seed germination and seedling vigour.

    PubMed

    Madejón, Paula; Cantos, Manuel; Jiménez-Ramos, María C; Marañón, Teodoro; Murillo, José M

    2015-11-01

    Seed germination is considered a critical phase in plant development and relatively sensitive to heavy metals. White poplar (Populus alba) trees tend to accumulate Cd and Zn in their tissues. We tested if soil contamination can affect P. alba progeny, reduced seed germination and explored the distribution of mineral elements in the seed. For this purpose, fruits and seeds from female P. alba trees were selected from two contaminated and one non-contaminated areas. Seeds from all the sites were germinated using only water or a nutritive solution (in vitro). Concentrations of nutrients and trace elements in the fruits and seeds were analysed. Seedling growth in vitro was also analysed. Finally, a mapping of different elements within the poplar seed was obtained by particle-induced X-ray emission (PIXE). Germination was similar between different progenies, refuting our hypothesis that seeds from a contaminated origin would have reduced germination capacity compared to those from a non-contaminated site. Seedling growth was not affected by the contaminated origin. Cadmium and Zn concentrations in fruits produced by P. alba trees in the contaminated sites were higher than by those from the non-contaminated site. However, the nutritional status of the trees was adequate in both cases. Cd in seedlings was higher in those from contaminated soils although lower than in fruits, indicating a certain exclusion from seeds. Preliminary results of the PIXE technique showed that Al and Zn were distributed uniformly in the seeds (Cd was not detected with this technique), while the nutrients P and S were concentrated in the cotyledons. PMID:26433900

  14. Incorporating Cache Management Behavior into Seed Dispersal: The Effect of Pericarp Removal on Acorn Germination

    PubMed Central

    Yi, Xianfeng; Zhang, Mingming; Bartlow, Andrew W.; Dong, Zhong

    2014-01-01

    Selecting seeds for long-term storage is a key factor for food hoarding animals. Siberian chipmunks (Tamias sibiricus) remove the pericarp and scatter hoard sound acorns of Quercus mongolica over those that are insect-infested to maximize returns from caches. We have no knowledge of whether these chipmunks remove the pericarp from acorns of other species of oaks and if this behavior benefits seedling establishment. In this study, we tested whether Siberian chipmunks engage in this behavior with acorns of three other Chinese oak species, Q. variabilis, Q. aliena and Q. serrata var. brevipetiolata, and how the dispersal and germination of these acorns are affected. Our results show that when chipmunks were provided with sound and infested acorns of Quercus variabilis, Q. aliena and Q. serrata var. brevipetiolata, the two types were equally harvested and dispersed. This preference suggests that Siberian chipmunks are incapable of distinguishing between sound and insect-infested acorns. However, Siberian chipmunks removed the pericarp from acorns of these three oak species prior to dispersing and caching them. Consequently, significantly more sound acorns were scatter hoarded and more infested acorns were immediately consumed. Additionally, indoor germination experiments showed that pericarp removal by chipmunks promoted acorn germination while artificial removal showed no significant effect. Our results show that pericarp removal allows Siberian chipmunks to effectively discriminate against insect-infested acorns and may represent an adaptive behavior for cache management. Because of the germination patterns of pericarp-removed acorns, we argue that the foraging behavior of Siberian chipmunks could have potential impacts on the dispersal and germination of acorns from various oak species. PMID:24647670

  15. Murine complement receptor 1 is required for germinal center B cell maintenance but not initiation

    PubMed Central

    Donius, Luke R.; Weis, Janis J.; Weis, John H.

    2014-01-01

    Germinal centers are the anatomic sites for the generation of high affinity immunoglobulin expressing plasma cells and memory B cells. The germinal center B cells that are precursors of these cells circulate between the light zone B cell population that interact with antigen laden follicular dendritic cells (FDC) and the proliferative dark zone B cell population. Antigen retention by follicular dendritic cells is dependent on Fc receptors and complement receptors, and complement receptor 1 (Cr1) is the predominant complement receptor expressed by FDC. The newly created Cr1KO mouse was used to test the effect of Cr1-deficiency on the kinetics of the germinal center reaction and the generation of IgM and switched memory B cell formation. Immunization of Cr1KO mice with a T cell-dependent antigen resulted in the normal initial expansion of B cells with a germinal center phenotype however these cells were preferentially lost in the Cr1KO animal over time (days). Bone marrow chimera animals documented the surprising finding that the loss of germinal center B cell maintenance was linked to the expression of Cr1 on B cells, not the FDC. Cr1-deficiency further resulted in antigen-specific IgM titer and IgM memory B cell reductions, but not antigen-specific IgG after 35-37 days. Investigations of nitrophenyl (NP)-specific IgG demonstrated that Cr1 is not necessary for affinity maturation during the response to particulate antigen. These data, along with those generated in our initial description of the Cr1KO animal describe unique functions of Cr1 on the surface of both B cells and FDC. PMID:24636730

  16. In vitro seed germination of economically important edible bamboo Dendrocalamus membranaceus Munro.

    PubMed

    Brar, Jasmine; Anand, Manju; Sood, Anil

    2013-01-01

    An in vitro propagation protocol using mature seeds of D. membranaceus was successfully established. Scarcity of seeds in bamboos because of their long flowering periods and irregular seed set resulting in low viability and germination potential, motivated us to undertake the present study. The effects of sterilants, light conditions, exogenous application of plant growth regulators and temperature in overcoming germination barriers in ageing seeds of bamboo were studied. It was found that HgCl2 (0.1%) along with bleach (15%) was more effective in raising aseptic cultures. Dark conditions, high temperatures around 30 degrees C and soaking of seeds in GA3 solution (50 ppm) overnight stimulated high percent of seed germination with corresponding increase in shoot length (2.7 +/- 0.7 mm) and number of sprouts (2.1 +/- 0.7) per explants during culture initiation. 6-benzylaminopurine acted synergistically with kinetin to give optimum germination rate of 70 +/- 13.9% as compared to 63.13% when used individually. For prolonged maintenance of cultures, 2% sucrose was found to be suitable for promoting photomixotrophic micropropagation. Following this procedure, about 65% survival of plantlets could be achieved during hardening. Biochemically seeds consume starchy endosperm for emergence of radicle which is taken as a sign of germination as also evident from the present study. Loss of viability and vigour after a year was confirmed by Tetrazolium chloride test. Micropropagation protocol developed here will ensure regeneration of large number of plants in a relatively short time. Conclusively, in vitro propagation protocol developed in D. membranaceus using mature seeds as an explants is reported for the first time. PMID:23441484

  17. Mycorrhizal fungi of Vanilla: diversity, specificity and effects on seed germination and plant growth.

    PubMed

    Porras-Alfaro, Andrea; Bayman, Paul

    2007-01-01

    Mycorrhizal fungi are essential for the germination of orchid seeds. However, the specificity of orchids for their mycorrhizal fungi and the effects of the fungi on orchid growth are controversial. Mycorrhizal fungi have been studied in some temperate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function of mycorrhizal fungi in Vanilla, a pantropical genus that is both terrestrial and epiphytic. Mycorrhizal roots were collected from four Vanilla species in Puerto Rico, Costa Rica and Cuba. Cultured and uncultured mycorrhizal fungi were identified by sequencing the internal transcribed spacer region of nuclear rDNA (nrITS) and part of the mitochondrial ribosomal large subunit (mtLSU), and by counting number of nuclei in hyphae. Vanilla spp. were associated with a wide range of mycorrhizal fungi: Ceratobasidium, Thanatephorus and Tulasnella. Related fungi were found in different species of Vanilla, although at different relative frequencies. Ceratobasidium was more common in roots in soil and Tulasnella was more common in roots on tree bark, but several clades of fungi included strains from both substrates. Relative frequencies of genera of mycorrhizal fungi differed significantly between cultured fungi and those detected by direct amplification. Ceratobasidium and Tulasnella were tested for effects on seed germination of Vanilla and effects on growth of Vanilla and Dendrobium plants. We found significant differences among fungi in effects on seed germination and plant growth. Effects of mycorrhizal fungi on Vanilla and Dendrobium were similar: a clade of Ceratobasidium had a consistently positive effect on plant growth and seed germination. This clade has potential use in germination and propagation of orchids. Results confirmed that a single orchid species can be associated with several mycorrhizal fungi with different functional consequences for the plant. PMID

  18. Effect of heat stress and oil formulation on conidial germination of Metarhizium anisopliae s.s. on tick cuticle and artificial medium.

    PubMed

    Barreto, Lucas P; Luz, Christian; Mascarin, Gabriel M; Roberts, Donald W; Arruda, Walquíria; Fernandes, Éverton K K

    2016-07-01

    The effect of heat stress (45°C) versus non-heat stress (27°C) on germination of Metarhizium anisopliae sensu stricto (s.s.) isolate IP 119 was examined with conidia formulated (suspended) in pure mineral oil or in water (Tween 80, 0.01%), and then applied onto the cuticle of Rhipicephalus sanguineus sensu lato (s.l.) engorged females or onto culture medium (PDAY). In addition, bioassays were performed to investigate the effect of conidia heated while formulated in oil, then applied to blood-engorged adult R. sanguineus females. Conidia suspended in water then exposed to 45°C, in comparison to conidia formulated in mineral oil and exposed to the same temperature, germinated less and more slowly when incubated on either PDAY medium or tick cuticle. Also, conidial germination on tick cuticle was delayed in comparison to germination on artificial culture medium; for example, germination was 13% on tick cuticle 72h after inoculation, in contrast to 61.5% on PDAY medium. Unheated (27°C) conidia suspended in either water or oil and applied to tick cuticle developed appressoria 36h after treatment; whereas only heat-stressed conidia formulated in oil developed appressoria on tick cuticle. In comparison to conidia heated in mineral oil, there was a strong negative effect of heat on germination of conidia heated in water before being applied to arthropod cuticle. Nevertheless, bioassays [based primarily on egg production (quantity) and egg hatchability] exhibited high percentages of tick control regardless of the type of conidial suspension; i.e., water- or oil-formulated conidia, and whether or not conidia were previously exposed to heat. In comparison to aqueous conidial preparations, however, conidia formulated in oil reduced egg hatchability irrespective of heat or no-heat exposure. In conclusion, mineral-oil formulation protected conidia against heat-induced delay of both germination and appressorium production when applied to the cuticle of R. sanguineus. PMID

  19. New error calibration tests for gravity models using subset solutions and independent data - Applied to GEM-T3

    NASA Technical Reports Server (NTRS)

    Lerch, F. J.; Nerem, R. S.; Chinn, D. S.; Chan, J. C.; Patel, G. B.; Klosko, S. M.

    1993-01-01

    A new method has been developed to provide a direct test of the error calibrations of gravity models based on actual satellite observations. The basic approach projects the error estimates of the gravity model parameters onto satellite observations, and the results of these projections are then compared with data residual computed from the orbital fits. To allow specific testing of the gravity error calibrations, subset solutions are computed based on the data set and data weighting of the gravity model. The approach is demonstrated using GEM-T3 to show that the gravity error estimates are well calibrated and that reliable predictions of orbit accuracies can be achieved for independent orbits.

  20. Bayesian meta-analysis of test accuracy in the absence of a perfect reference test applied to bone scintigraphy for the diagnosis of complex regional pain syndrome.

    PubMed

    Held, Ulrike; Brunner, Florian; Steurer, Johann; Wertli, Maria M

    2015-11-01

    There is conflicting evidence about the accuracy of bone scintigraphy (BS) for the diagnosis of complex regional pain syndrome 1 (CRPS 1). In a meta-analysis of diagnostic studies, the evaluation of test accuracy is impeded by the use of different imperfect reference tests. The aim of our study is to summarize sensitivity and specificity of BS for CRPS 1 and to identify factors to explain heterogeneity. We use a hierarchical Bayesian approach to model test accuracy and threshold, and we present different models accounting for the imperfect nature of the reference tests, and assuming conditional dependence between BS and the reference test results. Further, we include disease duration as explanatory variable in the model. The models are compared using summary ROC curves and the deviance information criterion (DIC). Our results show that those models which account for different imperfect reference tests with conditional dependence and inclusion of the covariate are the ones with the smallest DIC. The sensitivity of BS was 0.87 (95% credible interval 0.73-0.97) and the overall specificity was 0.87 (0.73-0.95) in the model with the smallest DIC, in which missing values of the covariate are imputed within the Bayesian framework. The estimated effect of duration of symptoms on the threshold parameter was 0.17 (-0.25 to 0.57). We demonstrate that the Bayesian models presented in this paper are useful to address typical problems occurring in meta-analysis of diagnostic studies, including conditional dependence between index test and reference test, as well as missing values in the study-specific covariates. PMID:26479506

  1. Freezing stress influences emergence of germinated perennial grass seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In sagebrush rangelands perennial bunchgrasses are typically seeded in fall and a high proportion of planted seeds germinate prior to winter onset but fail to emerge in spring. Our objectives were to evaluate freezing tolerance of germinated but non-emergent bluebunch wheatgrass seeds under laborat...

  2. The importance of seed germination in rangeland research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA, Agricultural Research Service (ARS)/ Great Basin Rangelands Research Unit, Wildland Seed Laboratory, located in Reno, NV, has been studying seed germination for the past 40 years. The wildland seed laboratory has collected, processed, and quantified germination characteristics of hundreds...

  3. Seed germination of five Poa species at negative water potentials

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Under field conditions water is often inadequate for satisfactory seed germination. An experiment was conducted to determine the effects of simulated dry conditions on germination and seedling growth of five bluegrass (Poa) species including: Texas, P. arachnifera Torr.; annual, P. annua L.; mutto...

  4. Investigating the Influence of Karrikins on Seed Germination

    ERIC Educational Resources Information Center

    de Beer, Josef

    2012-01-01

    Recent research has identified a karrikin (a butenolide derative) known as 3-methyl-2H-furo[2,3-c]pyran-2-one, formed from burning cellulose, that stimulates seed germination. Here, I present ideas on how to investigate the influence of karrikins on seed germination in the laboratory.

  5. Effect of NaCl on Germination of Sugar Beet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugar beet is a salt tolerant crop, but is most vulnerable to salinity during germination. The goal of this research is to examine the response to salinity on the germination of sugar beet, ultimately to provide germplasm that has an agronomic use in saline soils around the world. Expanding the char...

  6. Radish (Raphanus sativus) seed size affects germination response to coumarin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The inhibition of seed germination by an allelochemical is generally greater in small seeds than in large seeds. Studies reporting these results used a large number of plant species that varied in seed size, which might have introduced differences in germination characteristics or various parameter...

  7. The Significance of Hydrogen Sulfide for Arabidopsis Seed Germination

    PubMed Central

    Baudouin, Emmanuel; Poilevey, Aurélie; Hewage, Nishodi Indiketi; Cochet, Françoise; Puyaubert, Juliette; Bailly, Christophe

    2016-01-01

    Hydrogen sulfide (H2S) recently emerged as an important gaseous signaling molecule in plants. In this study, we investigated the possible functions of H2S in regulating Arabidopsis seed germination. NaHS treatments delayed seed germination in a dose-dependent manner and were ineffective in releasing seed dormancy. Interestingly, endogenous H2S content was enhanced in germinating seeds. This increase was correlated with higher activity of three enzymes (L-cysteine desulfhydrase, D-cysteine desulfhydrase, and β-cyanoalanine synthase) known as sources of H2S in plants. The H2S scavenger hypotaurine and the D/L cysteine desulfhydrase inhibitor propargylglycine significantly delayed seed germination. We analyzed the germinative capacity of des1 seeds mutated in Arabidopsis cytosolic L-cysteine desulfhydrase. Although the mutant seeds do not exhibit germination-evoked H2S formation, they retained similar germination capacity as the wild-type seeds. In addition, des1 seeds responded similarly to temperature and were as sensitive to ABA as wild type seeds. Taken together, these data suggest that, although its metabolism is stimulated upon seed imbibition, H2S plays, if any, a marginal role in regulating Arabidopsis seed germination under standard conditions. PMID:27446159

  8. An Arabidopsis thaliana embryo arrest mutant exhibiting germination potential

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to initiate radicle elongation, or germination potential, occurs in developing embryos before the completion of seed maturation. Green embryos after walking-stick stage in developing Arabidopsis thaliana seeds germinate when excised from seeds and incubated in MS media containing 1 % suc...

  9. The pleiotropic effects of the seed germination inhibitor germostatin.

    PubMed

    Ye, Yajin; Zhao, Yang

    2016-01-01

    Seed dormancy and germination are the most important adaptive traits of seed plants, which control the germination in a proper space and time. Internal genetic factors together with environmental cues govern seed dormancy and germination. Abscisic acid (ABA), a key phytohormone induces seed dormancy and inhibits seed germination through its molecular genetic signaling network responding the seed inherent physiological and environmental factors. Recently, auxin has been shown to be another phytohormone that induces seed dormancy. We have recently shown that germonstatin (GS), a small synthetic molecule identified by high through-put chemical genetic screenings, inhibits seed germination through up-regulating auxin signaling and inducing auxin biosynthesis. GERMOSTATIN RESISTANCE LOCUS 1 (GSR1) encodes a plant homeodomain (PHD) finger protein and is responsible for GS seed germination inhibition. Its knockdown mutant gsr1 displays decreased dormancy. In this report, we show that GS is not an ABA analog and provided 2 other GS-resistant mutants related to the chemical's function in seed germination inhibition other than gsr1, suggesting that GS may have pleiotropic effects through targeting different pathway governing seed germination. PMID:26918467

  10. Gibberellin Signaling: a Wake-up Call for Seed Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Making an appropriate decision to germinate is essential for the survival of plant species and is important for proper stand establishment in crop plants. Germination is regulated by the antagonistic effects to two plant hormones in Arabidopsis thaliana: abscisic acid (ABA) induces dormancy and repr...

  11. Lipids stimulate spore germination in the entomopathogenic ascomycete Ascosphaera aggregata.

    PubMed

    James, R R; Buckner, J S

    2004-10-01

    The alfalfa leafcutting bee (Megachile rotundata) is solitary and managed on a large scale for pollination of alfalfa seed crops. The bees nest in holes drilled in wood or polystyrene blocks, and their larvae are highly prone to a fungal disease called chalkbrood. The most prevalent form of chalkbrood is caused by Ascosphaera aggregata, but this ascomycete is difficult to culture. Hyphae will grow on standard fungal media, but spore germination is difficult to achieve and highly variable. We found that germination can be enhanced with oils. Lipids derived from plants and bee larvae increased germination from 50% (without oil) to 75-85% (with oil). Percent germination was significantly greater in the presence of lipids but germination was not significantly different when different oils, including mineral oil, were used. A. aggregata spores oriented along the oil-aqueous interface in the broth in a polar fashion, with swelling and germ tube formation always occurring into the aqueous portion of the broth. The other half of the spore tended to attach to a lipid droplet, where it remained, without swelling, during germ tube formation. The physical attachment of spores to the oil-aqueous interface is what most probably stimulates spore germination, as opposed to some nutritional stimulation. However, further research is needed to determine if and where the spores encounter such an interface when germinating in the host gut, where germination normally occurs. PMID:15645171

  12. The Importance of Seed Germination in Rangeland Research

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The USDA, Agricultural Research Service (ARS)/ Great Basin Rangelands Research Unit, Wildland Seed Laboratory, located in Reno, NV, has been studying seed germination for the past 40 years. The wildland seed laboratory has collected, processed, and quantified germination characteristics of hundreds...

  13. Seedling Vigor in Beta vulgaris: The Artistry of Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seedling vigor and stand establishment are two problems that growers have struggled with for decades. The initial conditions that a germinating seed encounters, and its ability to deal with them, affect the rate at which germination occurs, the rate of mobilization of stored energy reserves that the...

  14. Study for Germination Under Extreme Hypobaric and Hypoxic Condition

    NASA Astrophysics Data System (ADS)

    Hashimoto, H.

    2010-04-01

    In order to investigate a possibility of plant cultivation for the space agriculture on Mars, germination rate for six species of plant under extreme hypobaric and hypoxic condition was measured. As a result, seeds of Jute and Cucumber were able to germinate in six species.

  15. Proteins induced by salt stress in tomato germinating seeds

    SciTech Connect

    Torres-Shumann, S.; Godoy, J.A.; del Pozo, O.; Pintor-Toro, J.A. )

    1989-04-01

    Salt effects on protein synthesis in tomato germinating seeds were investigated by two-dimensional polyacrilamide gel electrophoresis of proteins labeled in vivo with ({sup 35}S)-Methionine. Seeds germinating in NaCl were analyzed at three germination stages (4mm long radicals, 15mm long radicles and expanding cotyledons) and compared to those germinating in water. At the first germination stage several basic proteins of M.W. 13Kd, 16Kd, 17Kd and 18Kd were detected in only salt germinating seeds. Other basic proteins of M.W. 12Kd, 50Kd and 54Kd were salt-induced at the second and third stage of germination. One 14Kd acid protein is observed in every assayed stage and shows several phosphorylated forms. The levels of expression of these proteins are directly correlated to assayed NaCl concentrations. All of these proteins, except 17Kd, are also induced by abscisic acid (ABA) in the same germination stages. A cooperative effect on the synthesis of these proteins is observed when both ABA and NaCl are present.

  16. A psychometric analysis of the reading the mind in the eyes test: toward a brief form for research and applied settings

    PubMed Central

    Olderbak, Sally; Wilhelm, Oliver; Olaru, Gabriel; Geiger, Mattis; Brenneman, Meghan W.; Roberts, Richard D.

    2015-01-01

    The Reading the Mind in the Eyes Test is a popular measure of individual differences in Theory of Mind that is often applied in the assessment of particular clinical populations (primarily, individuals on the autism spectrum). However, little is known about the test's psychometric properties, including factor structure, internal consistency, and convergent validity evidence. We present a psychometric analysis of the test followed by an evaluation of other empirically proposed and statistically identified structures. We identified, and cross-validated in a second sample, an adequate short-form solution that is homogeneous with adequate internal consistency, and is moderately related to Cognitive Empathy, Emotion Perception, and strongly related to Vocabulary. We recommend the use of this short-form solution in normal adults as a more precise measure over the original version. Future revisions of the test should seek to reduce the test's reliance on one's vocabulary and evaluate the short-form structure in clinical populations. PMID:26500578

  17. Controlling Guessing Bias in the Dichotomous Rasch Model Applied to a Large-Scale, Vertically Scaled Testing Program

    ERIC Educational Resources Information Center

    Andrich, David; Marais, Ida; Humphry, Stephen Mark

    2016-01-01

    Recent research has shown how the statistical bias in Rasch model difficulty estimates induced by guessing in multiple-choice items can be eliminated. Using vertical scaling of a high-profile national reading test, it is shown that the dominant effect of removing such bias is a nonlinear change in the unit of scale across the continuum. The…

  18. Applied Cognition: Testing the Effects of Independent Silent Reading on Secondary Students' Achievement and Attribution

    ERIC Educational Resources Information Center

    Cuevas, Joshua A.; Irving, Miles A.; Russell, L. Roxanne

    2014-01-01

    This study implemented an independent silent reading (ISR) program with 145 10th grade students. Students were measured on total reading ability, vocabulary, reading comprehension, a state-mandated high stakes end-of-course test (EOCT), and reading attribution. After controlling for initial skill and disposition levels, the results indicated that…

  19. Effect of some commonly used pesticides on seed germination, biomass production and photosynthetic pigments in tomato (Lycopersicon esculentum).

    PubMed

    Shakir, Shakirullah Khan; Kanwal, Memoona; Murad, Waheed; Zia ur Rehman; Shafiq ur Rehman; Daud, M K; Azizullah, Azizullah

    2016-03-01

    Pesticides are highly toxic substances. Their toxicity may not be absolutely specific to the target organisms but can adversely affect different processes in the non-target host plants. In the present study, the effect of over application of four commonly used pesticides (emamectin benzoate, alpha-cypermethrin, lambda-cyhalothrin and imidacloprid) was evaluated on the germination, seedling vigor and photosynthetic pigments in tomato. The obtained results revealed that seed germination was decreased by the pesticides and this effect was more prominent at early stages of exposure. All the tested pesticides reduced the growth of tomato when applied in higher concentration than the recommended dose, but at lower doses the pesticides had some stimulatory effects on growth as compared to the control. A similar effect of pesticides was observed on the photosynthetic pigments, i.e. a decrease in pigments concentrations was caused at higher doses but an increase was observed at lower doses of pesticides. The calculation of EC50 values for different parameters revealed the lowest EC50 values for emamectin (ranged as 51-181 mg/L) followed by alpha-cypermethrin (191.74-374.39), lambda-cyhalothrin (102.43-354.28) and imidacloprid (430.29-1979.66 mg/L). A comparison of the obtained EC50 values for different parameters of tomato with the recommended doses revealed that over application of these pesticides can be harmful to tomato crop. In a few cases these pesticides were found toxic even at the recommended doses. However, a field based study in this regard should be conducted to further verify these results. PMID:26603051

  20. Rice (Oryza sativa L.) Seed Sterilization and Germination Enhancement via Atmospheric Hybrid Nonthermal Discharge Plasma.

    PubMed

    Khamsen, Natthaporn; Onwimol, Damrongvudhi; Teerakawanich, Nithiphat; Dechanupaprittha, Sanchai; Kanokbannakorn, Weerawoot; Hongesombut, Komsan; Srisonphan, Siwapon

    2016-08-01

    We designed a system to produce atmospheric hybrid cold-discharge plasma (HCP) based on microcorona discharge on a single dielectric barrier and applied it to inactivate microorganisms that commonly attach the rice seed husk. The cold-plasma treatment modified the surface of the rice seeds, resulting in accelerated germination and enhanced water imbibition. The treatment can operate under air-based ambient conditions without the need for a vacuum. The cold-plasma treatment completely inactivated pathogenic fungi and other microorganisms, enhancing the germination percentage and seedling quality. The final germination percentage of the treated rice seeds was ∼98%, whereas that of the nontreated seeds was ∼90%. Microcorona discharge on a single dielectric barrier provides a nonaggressive cold plasma that can be applied to organic materials without causing thermal and electrical damage. The hybrid nonthermal plasma is cost effective and consumes relatively little power, making it suitable for the surface sterilization and disinfection of organic and biological materials with large-scale compatibility. PMID:27404121

  1. In situ histochemical localisation of alkaloids and acetogenins in the endosperm and embryonic axis of Annona macroprophyllata Donn. Sm. seeds during germination.

    PubMed

    Brechú-Franco, A E; Laguna-Hernández, G; De la Cruz-Chacón, I; González-Esquinca, A R

    2016-01-01

    Currently, the Annonaceae family is characterised by the production of acetogenins (ACGs), and also by the biosynthesis of alkaloids, primarily benzylisoquinolines derived from tyrosine. The objective of this study was to confirm the presence of alkaloids and acetogenins in the idioblasts of the endosperm and the embryonic axis of A. macroprophyllata seeds in germination. The Dragendorff, Dittmar, Ellram, and Lugol reagents were used to test for alkaloids, and Kedde's reagent was used to determine the presence of acetogenins in fresh sections of the endosperm and embryonic axis of seeds after twelve days of germination. A positive reaction was observed for all the reagents, and the presence of alkaloids and acetogenins was confirmed in the idioblasts of the endosperm and those involved in the differentiation of the embryonic axis of the developing seedling. We concluded that the idioblasts store both metabolites, acetogenins and alkaloids. Beginning at differentiation, the idioblasts of the embryonic axis simultaneously biosynthesise acetogenins and alkaloids that are characteristic of the species during the development of the seedling. The method used here can be applied to histochemically confirm the presence of acetogenins and alkaloids in tissues and structures of the plant in different stages of its life cycle. PMID:26972713

  2. In Situ Histochemical Localisation of Alkaloids and Acetogenins in the Endosperm and Embryonic Axis of Annona Macroprophyllata Donn. Sm. Seeds During Germination

    PubMed Central

    Brechú-Franco, A.E.; Laguna-Hernández, G.; De la Cruz-Chacón, I.; González-Esquinca, A.R.

    2016-01-01

    Currently, the Annonaceae family is characterised by the production of acetogenins (ACGs), and also by the biosynthesis of alkaloids, primarily benzylisoquinolines derived from tyrosine. The objective of this study was to confirm the presence of alkaloids and acetogenins in the idioblasts of the endosperm and the embryonic axis of A. macroprophyllata seeds in germination. The Dragendorff, Dittmar, Ellram, and Lugol reagents were used to test for alkaloids, and Kedde’s reagent was used to determine the presence of acetogenins in fresh sections of the endosperm and embryonic axis of seeds after twelve days of germination. A positive reaction was observed for all the reagents, and the presence of alkaloids and acetogenins was confirmed in the idioblasts of the endosperm and those involved in the differentiation of the embryonic axis of the developing seedling. We concluded that the idioblasts store both metabolites, acetogenins and alkaloids. Beginning at differentiation, the idioblasts of the embryonic axis simultaneously biosynthesise acetogenins and alkaloids that are characteristic of the species during the development of the seedling. The method used here can be applied to histochemically confirm the presence of acetogenins and alkaloids in tissues and structures of the plant in different stages of its life cycle. PMID:26972713

  3. Trace gas emissions and smoke-induced seed germination

    SciTech Connect

    Keeley, J.E.; Fotheringham, C.J.

    1997-05-23

    Dormant seeds of a California chaparral annual were induced to germinate by smoke or paper. Nitrogen oxides induced 100 percent vapors emitted from smoke-treated sand or treated water samples inducing. Smoke germination in a manner similar to smoke germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NO{sub 2})-treated samples. Vapors from smoke-treated and NO{sub 2}-treated filter paper had comparable NO{sub 2} flux rates. Chaparral wildfires generate sufficient nitrogen oxides from combustion of organic matter or from postfire biogenic nitrification to trigger germination of Emmerianthe penduliflora. Nitrogen oxide-triggered germination is not the result of changes in imbibition, as is the case with heat stimulated seeds.

  4. Coordination of seed dormancy and germination processes by MYB96.

    PubMed

    Lee, Kyounghee; Seo, Pil Joon

    2015-01-01

    The transition between seed dormancy and germination is an important stage that initiates plant life cycle. Hormonal balances of abscisic acid (ABA) and gibberellin (GA) contribute to determining the proper timing to germinate. Here, we demonstrate that the R2R3-type MYB96 transcription factor, a key ABA signaling mediator, coordinates seed dormancy and germination processes through distinct downstream events. This transcription factor controls ABA-INSENSITIVE 4 (ABI4) expression to inhibit seed germination by suppressing breakdown of lipid reserves in embryo. In addition, it also induces seed dormancy by stimulating ABA biosynthesis in an ABI4-independent manner. We propose that MYB96 integrates a multitude of environmental stress signals and acts as a master regulator in the determination of timing for seed germination. PMID:26313409

  5. Coordination of seed dormancy and germination processes by MYB96

    PubMed Central

    Lee, Kyounghee; Seo, Pil Joon

    2015-01-01

    The transition between seed dormancy and germination is an important stage that initiates plant life cycle. Hormonal balances of abscisic acid (ABA) and gibberellin (GA) contribute to determining the proper timing to germinate. Here, we demonstrate that the R2R3-type MYB96 transcription factor, a key ABA signaling mediator, coordinates seed dormancy and germination processes through distinct downstream events. This transcription factor controls ABA-INSENSITIVE 4 (ABI4) expression to inhibit seed germination by suppressing breakdown of lipid reserves in embryo. In addition, it also induces seed dormancy by stimulating ABA biosynthesis in an ABI4-independent manner. We propose that MYB96 integrates a multitude of environmental stress signals and acts as a master regulator in the determination of timing for seed germination. PMID:26313409

  6. Effect of Temperature, Light and Salinity on Seed Germination and Radicle Growth of the Geographically Widespread Halophyte Shrub Halocnemum strobilaceum

    PubMed Central

    Qu, Xiao-Xia; Huang, Zhen-Ying; Baskin, Jerry M.; Baskin, Carol C.

    2008-01-01

    Background and Aims The small leafy succulent shrub Halocnemum strobilaceum occurs in saline habitats from northern Africa and Mediterranean Europe to western Asia, and it is a dominant species in salt deserts such as those of north-west China. The effects of temperature, light/darkness and NaCl salinity were tested on seed germination, and the effects of salinity were tested on seed germination recovery, radicle growth and radicle elongation recovery, using seeds from north-west China; the results were compared with those previously reported on this species from ‘salt steppes’ in the Mediterranean region of Spain. Methods Seed germination was tested over a range of temperatures in light and in darkness and over a range of salinities at 25 °C in the light. Seeds that did not germinate in the NaCl solutions were tested for germination in deionized water. Seeds from which radicles had barely emerged in deionized water were transferred to NaCl solutions for 10 d and then back to deionized water for 10 d to test for radicle growth and recovery. Key Results Seeds germinated to higher percentages in light than in darkness and at high than at low temperatures. Germination percentages decreased with an increase in salinity from 0·1 to 0·75 m NaCl. Seeds that did not germinate in NaCl solutions did so after transfer to deionized water. Radicle elongation was increased by low salinity, and then it decreased with an increase in salinity, being completely inhibited by ≥2·0 m NaCl. Elongation of radicles from salt solutions <3·0 m resumed after seedlings were transferred to deionized water. Conclusions The seed and early seedling growth stages of the life cycle of H. strobilaceum are very salt tolerant, and their physiological responses differ somewhat between the Mediterranean ‘salt steppe’ of Spain and the inland cold salt desert of north-west China. PMID:17428834

  7. Impact of hydrocarbons from a diesel fuel on the germination and early growth of subantarctic plants.

    PubMed

    Macoustra, Gabriella K; King, Catherine K; Wasley, Jane; Robinson, Sharon A; Jolley, Dianne F

    2015-07-01

    Special Antarctic Blend (SAB) is a diesel fuel dominated by aliphatic hydrocarbons that is commonly used in Antarctic and subantarctic regions. The past and present use of SAB fuel at Australia's scientific research stations has resulted in multiple spills, contaminating soils in these pristine areas. Despite this, no soil quality guidelines or remediation targets have been developed for the region, primarily due to the lack of established indigenous test species and subsequent biological effects data. In this study, twelve plant species native to subantarctic regions were collected from Macquarie Island and evaluated to determine their suitably for use in laboratory-based toxicity testing, using germination success and seedling growth (shoot and root length) as endpoints. Two soil types (low and high organic carbon (OC)) were investigated to reflect the variable OC content found in soils on Macquarie Island. These soils were spiked with SAB fuel and aged for 14 days to generate a concentration series of SAB-contaminated soils. Exposure doses were quantified as the concentration of total petroleum hydrocarbons (TPH, nC9-nC18) on a soil dry mass basis. Seven species successfully germinated on control soils under laboratory conditions, and four of these species (Colobanthus muscoides Hook.f., Deschampsia chapmanii Petrie, Epilobium pendunculare A.Cunn. and Luzula crinita Hook.f.) showed a dose-dependent inhibition of germination when exposed to SAB-contaminated soils. Contaminated soils with low OC were generally more toxic to plants than high organic carbon soils. Increasing soil-TPH concentrations significantly inhibited shoot and root growth, and root length was identified as the most sensitive endpoint. Although the test species were tolerant to SAB-contaminated soils in germination assays, development of early life stages (up to 28 days) were generally more sensitive indicator of exposure effects, and may be more useful endpoints for future testing. PMID

  8. Rocket plume spectrometry: A system permitting engine condition monitoring, as applied to the technology test bed engine

    NASA Technical Reports Server (NTRS)

    Powers, W. T.

    1989-01-01

    The appearance of visible objects in the exhaust plume of space shuttle main engines (SSME) during test firings is discussed. A program was undertaken to attempt to identify anomalous material resulting from wear, normal or excessive, of internal parts, allowing time monitoring of engine condition or detection of failure precursors. Measurements were taken during test firings at Stennis Space Center and at the Santa Suzanna facility in California. The results indicated that a system having high spectral resolution, a fast time response, and a wide spectral range was required to meet all requirements, thus two special systems have been designed and built. One is the Optical Plume Anomaly Detector (OPAD). The other instrument, which is described in this report, is the superspectrometer, an optical multichannel analyzer having 8,192 channels covering the spectral band 250 to 1,000 nm.

  9. The design, testing and evaluation of the MIT individual-blade-control system as applied to gust alleviation for helicopters

    NASA Technical Reports Server (NTRS)

    Mckillip, R. M., Jr.

    1980-01-01

    A type of active control for helicopters was designed and tested on a four foot diameter model rotor. A single blade was individually controlled in pitch in the rotating frame over a wide range of frequencies by electromechanical means. By utilizing a tip mounted accelerometer as a sensor in the feedback path, significant reductions in blade flapping response to gust were achieved at the gust excitation frequency as well as at super and subharmonics of rotor speed.

  10. Generation of Recombinant Rabies Virus CVS-11 Expressing eGFP Applied to the Rapid Virus Neutralization Test

    PubMed Central

    Xue, Xianghong; Zheng, Xuexing; Liang, Hongru; Feng, Na; Zhao, Yongkun; Gao, Yuwei; Wang, Hualei; Yang, Songtao; Xia, Xianzhu

    2014-01-01

    The determination of levels of rabies virus-neutralizing antibody (VNA) provides the foundation for the quantitative evaluation of immunity effects. The traditional fluorescent antibody virus neutralization test (FAVN) using a challenge virus standard (CVS)-11 strain as a detection antigen and staining infected cells with a fluorescein isothiocyanate (FITC)-labeled monoclonal antibody, is expensive and high-quality reagents are often difficult to obtain in developing countries. Indeed, it is essential to establish a rapid, economical, and specific rabies virus neutralization test (VNT). Here, we describe a recombinant virus rCVS-11-eGFP strain that stably expresses enhanced green fluorescent protein (eGFP) based on a reverse genetic system of the CVS-11 strain. Compared to the rCVS-11 strain, the rCVS-11-eGFP strain showed a similar growth property with passaging stability in vitro and pathogenicity in vivo. The rCVS-11-eGFP strain was utilized as a detection antigen to determine the levels of rabies VNAs in 23 human and 29 canine sera; this technique was termed the FAVN-eGFP method. The good reproducibility of FAVN-eGFP was tested with partial serum samples. Neutralization titers obtained from FAVN and FAVN-eGFP were not significantly different. The FAVN-eGFP method allows rapid economical, specific, and high-throughput assessment for the titration of rabies VNAs. PMID:24714411

  11. Generation of recombinant rabies Virus CVS-11 expressing eGFP applied to the rapid virus neutralization test.

    PubMed

    Xue, Xianghong; Zheng, Xuexing; Liang, Hongru; Feng, Na; Zhao, Yongkun; Gao, Yuwei; Wang, Hualei; Yang, Songtao; Xia, Xianzhu

    2014-04-01

    The determination of levels of rabies virus-neutralizing antibody (VNA) provides the foundation for the quantitative evaluation of immunity effects. The traditional fluorescent antibody virus neutralization test (FAVN) using a challenge virus standard (CVS)-11 strain as a detection antigen and staining infected cells with a fluorescein isothiocyanate (FITC)-labeled monoclonal antibody, is expensive and high-quality reagents are often difficult to obtain in developing countries. Indeed, it is essential to establish a rapid, economical, and specific rabies virus neutralization test (VNT). Here, we describe a recombinant virus rCVS-11-eGFP strain that stably expresses enhanced green fluorescent protein (eGFP) based on a reverse genetic system of the CVS-11 strain. Compared to the rCVS-11 strain, the rCVS-11-eGFP strain showed a similar growth property with passaging stability in vitro and pathogenicity in vivo. The rCVS-11-eGFP strain was utilized as a detection antigen to determine the levels of rabies VNAs in 23 human and 29 canine sera; this technique was termed the FAVN-eGFP method. The good reproducibility of FAVN-eGFP was tested with partial serum samples. Neutralization titers obtained from FAVN and FAVN-eGFP were not significantly different. The FAVN-eGFP method allows rapid economical, specific, and high-throughput assessment for the titration of rabies VNAs. PMID:24714411

  12. Experimental test program for evaluation of solid lubricant coating as applied to compliant foil gas bearings to 315 deg C

    NASA Technical Reports Server (NTRS)

    Wagner, R. C.

    1985-01-01

    An experimental apparatus and test procedure was developed to compare the performance of two solid lubricant coatings for air lubricated compliant foil gas bearings in the temperature range of 25 to 315 C. Polyimide bonded additive (SBGC) were tested extensively for durability and frictional characteristics. A partial arc bearing constructed of Inconel X-750 was coated on the bore with one of these coatings. The foil was subjected to repeated start/stop cycles. Performance comparisons reveal that although both coatings survive thousands of start/stop cycles, only the PBGF coated bearing achieves the specified 9000 start/stops. There is enough wear on the SBGC coated bearing to warrant termination of the test prior to 9000 start/stop cycles due to coating failure. The frictional characteristics of the PBGF are better at the elevated temperatures than at lower temperatures; a marked increase in sliding friction occurs as the temperature decreases. The SBGC maintains relatively constant frictional characteristics independent of operating temperature.

  13. Mass Spectrometry Applied to Bottom-Up Proteomics: Entering the High-Throughput Era for Hypothesis Testing.

    PubMed

    Gillet, Ludovic C; Leitner, Alexander; Aebersold, Ruedi

    2016-06-12

    Proteins constitute a key class of molecular components that perform essential biochemical reactions in living cells. Whether the aim is to extensively characterize a given protein or to perform high-throughput qualitative and quantitative analysis of the proteome content of a sample, liquid chromatography coupled to tandem mass spectrometry has become the technology of choice. In this review, we summarize the current state of mass spectrometry applied to bottom-up proteomics, the approach that focuses on analyzing peptides obtained from proteolytic digestion of proteins. With the recent advances in instrumentation and methodology, we show that the field is moving away from providing qualitative identification of long lists of proteins to delivering highly consistent and accurate quantification values for large numbers of proteins across large numbers of samples. We believe that this shift will have a profound impact for the field of proteomics and life science research in general. PMID:27049628

  14. Mass Spectrometry Applied to Bottom-Up Proteomics: Entering the High-Throughput Era for Hypothesis Testing

    NASA Astrophysics Data System (ADS)

    Gillet, Ludovic C.; Leitner, Alexander; Aebersold, Ruedi

    2016-06-01

    Proteins constitute a key class of molecular components that perform essential biochemical reactions in living cells. Whether the aim is to extensively characterize a given protein or to perform high-throughput qualitative and quantitative analysis of the proteome content of a sample, liquid chromatography coupled to tandem mass spectrometry has become the technology of choice. In this review, we summarize the current state of mass spectrometry applied to bottom-up proteomics, the approach that focuses on analyzing peptides obtained from proteolytic digestion of proteins. With the recent advances in instrumentation and methodology, we show that the field is moving away from providing qualitative identification of long lists of proteins to delivering highly consistent and accurate quantification values for large numbers of proteins across large numbers of samples. We believe that this shift will have a profound impact for the field of proteomics and life science research in general.

  15. Responses of seed germination, seedling growth, and seed yield traits to seed pretreatment in maize (Zea mays L.).

    PubMed

    Tian, Yu; Guan, Bo; Zhou, Daowei; Yu, Junbao; Li, Guangdi; Lou, Yujie

    2014-01-01

    A series of seed priming experiments were conducted to test the effects of different pretreatment methods to seed germination, seedling growth, and seed yield traits in maize (Zea mays L.). Results indicated that the seeds primed by gibberellins (GA), NaCl, and polyethylene glycol (PEG) reagents showed a higher imbibitions rate compared to those primed with water. The final germination percentage and germination rate varied with different reagents significantly (P < 0.05). The recommended prime reagents were GA at 10 mg/L, NaCl at 50 mM, and PEG at 15% on account of germination experiment. 15% PEG priming reagent increased shoot and root biomass of maize seedling. The shoot biomass of seedlings after presoaking the seeds with NaCl reagent was significantly higher than the seedlings without priming treatment. No significant differences of plant height, leaf number, and hundred-grain weight were observed between control group and priming treatments. Presoaking with water, NaCl (50 mM), or PEG (15%) significantly increased the hundred-grain weight of maize. Therefore, seed pretreatment is proved to be an effective technique to improve the germination performance, seedling growth, and seed yield of maize. However, when compared with the two methods, if immediate sowing is possible, presoaking is recommended to harvest better benefits compared to priming method. PMID:25093210

  16. The effect of altitude on breaking seed dormancy and stimulation of seed germination of Persian hogweed (Heracleum persicum).

    PubMed

    Salehani, M Khajavi; Mahmoudi, J; Mahdavi, S Kh; Habibzadeh, R

    2013-01-01

    Persian hogweed is a perennial herb and aromatic plant which has pharmaceutical and fodder values, and the main propagation method of this species is seed. The goal of this study was to investigate the effect of altitude on breaking dormancy and stimulate seed germination of this species. The study was designed and carried out using the test of seed analysis. For our purpose, seeds were collected from three different altitudes (1700, 2200, 2700 masl) in Kojoor area. After initial purification, germination percent (GP) and speed (GS) of each elevation were determined by cold stratification compared to control. According to results, control seeds did not germinate, showing that the seeds of this species need to be treated. Statistical analysis of results showed that there are significant differences between GP and GS of each elevation, as seeds of higher elevation had slower and less germination in longer periods. So, changes in elevation are an effective factor on seed germination characteristics of this species and this factor has to be considered in seed preparation and restoration with this species. PMID:24311887

  17. Interference with the germination and growth of Ulva zoospores by quorum-sensing molecules from Ulva-associated epiphytic bacteria.

    PubMed

    Twigg, Matthew S; Tait, Karen; Williams, Paul; Atkinson, Steve; Cámara, Miguel

    2014-02-01

    Ulva zoospores preferentially settle on N-acylhomoserine lactone (AHL) producing marine bacterial biofilms. To investigate whether AHL signal molecules also affect the success and rate of zoospore germination in addition to zoospore attraction, the epiphytic bacteria associated with mature Ulva linza were characterized and bacterial isolates representative of this community tested for the ability to produce AHLs. Two of these AHL-producing isolates, Sulfitobacter spp. 376 and Shewanella spp. 79, were transformed with plasmids expressing the Bacillus spp. AHL lactonase gene aiiA to generate AHL-deficient variants. The germination and growth of U. linza zoospores was studied in the presence of these AHL-deficient strains and their AHL-producing counterparts. This revealed that the AHLs produced by Sulfitobacter spp. and Shewanella spp. or the bacterial products they regulate have a negative impact on both zoospore germination and the early growth of the Ulva germling. Further experiments with Escherichia coli biofilms expressing recombinant AHL synthases and synthetic AHLs provide data to demonstrate that zoospores germinated and grown in the absence of AHLs were significantly longer than those germinated in the presence of AHLs. These results reveal an additional role for AHLs per se in the interactive relationships between marine bacteria and Ulva zoospores. PMID:23879807

  18. Responses of Seed Germination, Seedling Growth, and Seed Yield Traits to Seed Pretreatment in Maize (Zea mays L.)

    PubMed Central

    Tian, Yu; Guan, Bo; Zhou, Daowei; Li, Guangdi; Lou, Yujie

    2014-01-01

    A series of seed priming experiments were conducted to test the effects of different pretreatment methods to seed germination, seedling growth, and seed yield traits in maize (Zea mays L.). Results indicated that the seeds primed by gibberellins (GA), NaCl, and polyethylene glycol (PEG) reagents showed a higher imbibitions rate compared to those primed with water. The final germination percentage and germination rate varied with different reagents significantly (P < 0.05). The recommended prime reagents were GA at 10 mg/L, NaCl at 50 mM, and PEG at 15% on account of germination experiment. 15% PEG priming reagent increased shoot and root biomass of maize seedling. The shoot biomass of seedlings after presoaking the seeds with NaCl reagent was significantly higher than the seedlings without priming treatment. No significant differences of plant height, leaf number, and hundred-grain weight were observed between control group and priming treatments. Presoaking with water, NaCl (50 mM), or PEG (15%) significantly increased the hundred-grain weight of maize. Therefore, seed pretreatment is proved to be an effective technique to improve the germination performance, seedling growth, and seed yield of maize. However, when compared with the two methods, if immediate sowing is possible, presoaking is recommended to harvest better benefits compared to priming method. PMID:25093210

  19. Effect of sewage water on seed germination and vigour index of different varieties of groundnut (Arachis hypogaea L.).

    PubMed

    Girisha, S T; Raju, N S

    2008-11-01

    The study has been focused on the investigation on ground nut (Arachis hypogea) fields influenced by sewage water. Sewage water sampled in and around Mysore city and analyzed forphysicochemical parameters. Different concentrations such as 1, 5, 10, 25, 50, 70 and 100% of sewage water on seed germination and vigour index of Arachis hypogea verities such as DH - 2 - 30, ICJS - 11, JL - 24, K - 134, TMV - 2 and VRI - 2 were studied. From the recorded observation it is concluded that the sewage water diluted to 25% concentration for irrigation of groundnut enhances germination percentage and vigour index in K- 134 variety which is more susceptible than other tested varieties. PMID:19297996

  20. Within-and among-year germination in Sonoran Desert winter annuals: bet hedging and predictive germination in a variable environment.

    PubMed

    Gremer, Jennifer R; Kimball, Sarah; Venable, D Lawrence

    2016-10-01

    In variable environments, organisms must have strategies to ensure fitness as conditions change. For plants, germination can time emergence with favourable conditions for later growth and reproduction (predictive germination), spread the risk of unfavourable conditions (bet hedging) or both (integrated strategies). Here we explored the adaptive value of within- and among-year germination timing for 12 species of Sonoran Desert winter annual plants. We parameterised models with long-term demographic data to predict optimal germination fractions and compared them to observed germination. At both temporal scales we found that bet hedging is beneficial and that predicted optimal strategies corresponded well with observed germination. We also found substantial fitness benefits to varying germination timing, suggesting some degree of predictive germination in nature. However, predictive germination was imperfect, calling for some degree of bet hedging. Together, our results suggest that desert winter annuals have integrated strategies combining both predictive plasticity and bet hedging. PMID:27515951

  1. Rare earth elements (REEs): effects on germination and growth of selected crop and native plant species.

    PubMed

    Thomas, Philippe J; Carpenter, David; Boutin, Céline; Allison, Jane E

    2014-02-01

    The phytotoxicity of rare earth elements (REEs) is still poorly understood. The exposure-response relationships of three native Canadian plant species (common milkweed, Asclepias syriaca L., showy ticktrefoil, Desmodium canadense (L.) DC. and switchgrass, Panicum virgatum L.) and two commonly used crop species (radish, Raphanus sativus L., and tomato, Solanum lycopersicum L.) to the REEs lanthanum (La), yttrium (Y) and cerium (Ce) were tested. In separate experiments, seven to eight doses of each element were added to the soil prior to sowing seeds. Effects of REE dose on germination were established through measures of total percent germination and speed of germination; effects on growth were established through determination of above ground biomass. Ce was also tested at two pH levels and plant tissue analysis was conducted on pooled samples. Effects on germination were mostly observed with Ce at low pH. However, effects on growth were more pronounced, with detectable inhibition concentrations causing 10% and 25% reductions in biomass for the two native forb species (A. syriaca and D. canadense) with all REEs and on all species tested with Ce in both soil pH treatments. Concentration of Ce in aboveground biomass was lower than root Ce content, and followed the dose-response trend. From values measured in natural soils around the world, our results continue to support the notion that REEs are of limited toxicity and not considered extremely hazardous to the environment. However, in areas where REE contamination is likely, the slow accumulation of these elements in the environment could become problematic. PMID:23978671

  2. Evaluation of phytotoxicity effect of olive mill wastewater treated by different technologies on seed germination of barley (Hordeum vulgare L.).

    PubMed

    Rusan, Munir J M; Albalasmeh, Ammar A; Zuraiqi, Said; Bashabsheh, Mohammad

    2015-06-01

    Olive-mill wastewater (OMW) is a by-product effluent of olive oil extraction process that is produced in large amount in the Mediterranean region. OMW is believed to induce phytotoxic effect on organisms including seed germination and plant growth. The objective of this study was to evaluate the impact of untreated and treated OMW with different techniques on seed germination of barley (Hordeum vulgare L.). The following treatments were investigated: (1) tap water (control); (2) OMW treated by aerobic biological technology in a Jacto Reactor (JR); (3) OMW treated by solar fenton oxidation (SFO); (4) OMW treated by microfiltration followed by nanofiltration (MF+NF); (5) OMW treated by microfiltration followed by reverse osmosis (MF+RO) process; (6) diluted OMW with tap water (25 % OMW); (7) diluted OMW with tap water (50 % OMW); (8) diluted OMW with tap water (75 % OMW); and (9) untreated OMW (100 % OMW). A germination test was conducted in an incubator at temperature of 23 (∘)C. In each petri dish, a filter paper was mounted and ten seeds of barley were placed on the filter paper. Five milliliter of water were added to each petri dish. The seed germination was determined by counting the number of germinated seeds to calculate the percentage of germination (G %). Germination rate index (GRI), seed vigor index (SVI), and phytotoxicity index (PI) were also calculated. Then, the dry weights and lengths of the shoots and the roots of the germinated seeds were measured. The results show that 100, 75, and 50 %OMW were very phytotoxic and completely prohibited seed germination. However, phytotoxicity decreased significantly following treatments of OMW with all techniques investigated and by the 25 % OMW dilution, as results of removing the phenols and other phytotoxic organic compounds from the OMW or by diluting it. This was evidenced by relative enhancement of the dry weights and lengths of shoot and root as well as the G %, GRI, SVG, and PI. It was concluded that if

  3. Applying the Triangle Taste Test to Assess Differences between Low Sodium Salts and Common Salt: Evidence from Peru

    PubMed Central

    Saavedra-Garcia, Lorena; Bernabe-Ortiz, Antonio; Gilman, Robert H.; Diez-Canseco, Francisco; Cárdenas, María Kathia; Sacksteder, Katherine A.; Miranda, J. Jaime

    2015-01-01

    Background In resourced-constrained settings, daily cooking practices are still the norm. Replacing sodium in regular salt to produce potassium-enriched salts are potential alternative routes to reduce sodium intake, paired with the benefit associated with potassium intake. This change would likely have effects on palatability and taste of prepared foods, yet a threshold to discriminate sensorial changes can be determined. The main goal of this study was to assess if the use of potassium-enriched salt substitutes lead to perceived differences in taste utilizing a sensory discrimination test. Methods and Results A triangle taste test was conducted and participants were offered samples of cooked rice prepared with different salts. The only ingredient that differed in the preparation was the salt used: 100%NaCl (regular salt) and salts where sodium was replaced by 50%, 33% or 25% KCl (potassium-enriched salt). Comparisons were carried out according to the minimum number of correct judgments. A total of 156 subjects, 49% males, mean age 41.0 years (SD±15.5) years, participated in the study. Samples using 25% potassium-enrichment were indistinguishable in terms of taste from regular salt, whereas samples with 33% and 50% potassium-enrichment were distinguishable. Results were consistent when stratified by sex and age. Less than 10% of participants attributed the differences to bitterness or metallic flavor. Conclusions The 25% potassium-enriched salt is indistinguishable from regular salt. These findings suggest a potential to achieve sodium intake reduction strategies in cooking practices by substituting regular salt with potassium-enriched salt without affecting palatability. PMID:26225848

  4. Effects of after-ripening and storage regimes on seed germination behavior of seven species of Physaria germplasm

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The after-ripening response has been well documented in many plant species but studies of this topic are lacking in many new oilseed crops such as Physaria. In a factorial experiment, we tested the effect of different after-ripening periods and germination conditions on freshly harvested seeds of se...

  5. Adjuvant and refined corn oil formulation effects on conidial germination, appressorial formation and virulence of the bioherbicide, Colletotrichum truncatum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several surfactants, plant extracts, and fatty acids were tested for stimulation of conidial germination and appressorial formation of Colletotrichum truncatum, a bioherbicide of the weed, hemp sesbania (Sesbania exaltata). The commercial surfactants (Tweens® 40, 60, 80, 85 and Myvatex® 60) at conc...

  6. Effects of after-ripening and storage regimes on seed-germination behavior of seven species of Physaria

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The after-ripening response has been well documented in many plant species but studies of this topic are lacking in many new oilseed crops such as Physaria. In a factorial experiment, we tested the effect of different after-ripening periods and germination conditions on freshly harvested seeds of se...

  7. Germination and early plant development of ten plant species exposed to titanium dioxide and cerium oxide nanoparticles

    EPA Science Inventory

    Ten agronomic plant species were exposed to different concentrations of nano titanium dioxide (nTiO2) or nano cerium oxide (nCeO2) (0, 250, 500 and 1000 mg/L) to examine potential effects on germination and early seedling development. We modified a standard test protocol develop...

  8. Sporulation and germination gene expression analysis of Bacillus anthracis Sterne spores in skim milk under heat and different intervention techniques

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To investigate how B. anthracis Stene spores survive in milk under heat (80 degree C, 10 minutes), pasteurization (72 degree C, 15 seconds) and pasteurization plus microfiltration, the expression levels of genes that related to sporulation and germination were tested using real-time PCR assays. Tw...

  9. Visualizing antibody affinity maturation in germinal centers.

    PubMed

    Tas, Jeroen M J; Mesin, Luka; Pasqual, Giulia; Targ, Sasha; Jacobsen, Johanne T; Mano, Yasuko M; Chen, Casie S; Weill, Jean-Claude; Reynaud, Claude-Agnès; Browne, Edward P; Meyer-Hermann, Michael; Victora, Gabriel D

    2016-03-01

    Antibodies somatically mutate to attain high affinity in germinal centers (GCs). There, competition between B cell clones and among somatic mutants of each clone drives an increase in average affinity across the population. The extent to which higher-affinity cells eliminating competitors restricts clonal diversity is unknown. By combining multiphoton microscopy and sequencing, we show that tens to hundreds of distinct B cell clones seed each GC and that GCs lose clonal diversity at widely disparate rates. Furthermore, efficient affinity maturation can occur in the absence of homogenizing selection, ensuring that many clones can mature in parallel within the same GC. Our findings have implications for development of vaccines in which antibodies with nonimmunodominant specificities must be elicited, as is the case for HIV-1 and influenza. PMID:26912368

  10. Applying a gender lens on human papillomavirus infection: cervical cancer screening, HPV DNA testing, and HPV vaccination

    PubMed Central

    2013-01-01

    Background Our aim is to provide a state-of-the-art overview of knowledge on sex (biological) and gender (sociocultural) aspects of Human papillomavirus (HPV) and cervical cancer for educational purposes. Considerable disparities exist in cervical cancer incidences between different subgroups of women. We provide an outline on the crucial issues and debates based on the recent literature published in leading gender medicine journals. Intersectionality was applied in order to help categorise the knowledge. Methods Key terms (HPV, cervical cancer) were screened in Gender Medicine, Journal of Women’s Health and Women & Health from January 2005-June 2012. Additional searches were conducted for topics insufficiently mentioned, such as HPV vaccination of boys. In total, 71 publications were included (56 original papers, four reviews, six reports, three commentaries, one editorial and one policy statement). Results Research reveals complexity in the way various subgroups of women adhere to cervical screening. Less educated women, older women, uninsured women, homeless women, migrant women facing language barriers, women who have sex with women and obese women participate in Pap smears less frequently. A series of barriers can act to impede decisions to vaccinate against HPV. Conclusions Both male and female controlled preventive methods and treatment measures should be developed in order to tackle HPV infection and different strategies are needed for different subgroups. A substantial discussion and research on alternative methods of prevention was and is lacking. In future research, sex and gender aspects of HPV-related diseases of boys and men as well as subgroup differences in HPV risk need to be addressed. PMID:23394214

  11. Delta distributary dynamics in the Skagit River Delta (Washington, USA): Extending, testing, and applying avulsion theory in a tidal system

    NASA Astrophysics Data System (ADS)

    Hood, W. Gregory

    2010-11-01

    Analysis of historical aerial photos shows that Skagit Delta (Washington, USA) distributary dynamics are consistent with the Slingerland and Smith model of avulsion dynamics where the ratio of the water surface slopes of the two branches of a bifurcation predicts avulsion stability. This model was extended to predict distributary inlet (upstream) width and bankfull cross-sectional area. The water surface gradient ratio for a bifurcation pair predicted distributary width well; the lowest R2 was 0.61 for the 1937 data points, but R2 ranged from 0.83 to 0.90 for other year-specific regression lines. Gradient ratios were not constant over the historical record; from 1937 to 1972 the mainstem river channel lengthened by 1250 m in the course of marsh progradation, while distributary lengthening was comparatively negligible. Consequently, the gradient advantage of the distributaries increased and their channels widened. After the mainstem river terminus stabilized from 1972 to the present, the distributaries continued to lengthen with marsh progradation, so that distributary gradient advantage steadily declined and the distributaries narrowed. While distributary cross sections were not available for the historical period, they were surveyed in 2007 near the distributary inlets. Gradient ratio was more closely related to distributary inlet bankfull cross-sectional area ( R2 = 0.95) than to minimum distributary width for any photo year examined. Applying this form of analysis to Skagit Delta distributaries that have been dammed in the course of agricultural development suggests that their restoration to stabilize eroding marshes at their outlets and recover salmon migration pathways would be feasible without significant risk of full river avulsion.

  12. Involvement of Alternative Splicing in Barley Seed Germination.

    PubMed

    Zhang, Qisen; Zhang, Xiaoqi; Wang, Songbo; Tan, Cong; Zhou, Gaofeng; Li, Chengdao

    2016-01-01

    Seed germination activates many new biological processes including DNA, membrane and mitochondrial repairs and requires active protein synthesis and sufficient energy supply. Alternative splicing (AS) regulates many cellular processes including cell differentiation and environmental adaptations. However, limited information is available on the regulation of seed germination at post-transcriptional levels. We have conducted RNA-sequencing experiments to dissect AS events in barley seed germination. We identified between 552 and 669 common AS transcripts in germinating barley embryos from four barley varieties (Hordeum vulgare L. Bass, Baudin, Harrington and Stirling). Alternative 3' splicing (34%-45%), intron retention (32%-34%) and alternative 5' splicing (16%-21%) were three major AS events in germinating embryos. The AS transcripts were predominantly mapped onto ribosome, RNA transport machineries, spliceosome, plant hormone signal transduction, glycolysis, sugar and carbon metabolism pathways. Transcripts of these genes were also very abundant in the early stage of seed germination. Correlation analysis of gene expression showed that AS hormone responsive transcripts could also be co-expressed with genes responsible for protein biosynthesis and sugar metabolisms. Our RNA-sequencing data revealed that AS could play important roles in barley seed germination. PMID:27031341

  13. Studies on the molecular mechanisms of seed germination.

    PubMed

    Han, Chao; Yang, Pingfang

    2015-05-01

    Seed germination that begins with imbibition and ends with radicle emergence is the first step for plant growth. Successful germination is not only crucial for seedling establishment but also important for crop yield. After being dispersed from mother plant, seed undergoes continuous desiccation in ecosystem and selects proper environment to trigger germination. Owing to the contribution of transcriptomic, proteomic, and molecular biological studies, molecular aspect of seed germination is elucidated well in Arabidopsis. Recently, more and more proteomic and genetic studies concerning cereal seed germination were performed on rice (Oryza sativa) and barley (Hordeum vulgare), which possess completely different seed structure and domestication background with Arabidopsis. In this review, both the common features and the distinct mechanisms of seed germination are compared among different plant species including Arabidopsis, rice, and maize. These features include morphological changes, cell and its related structure recovery, metabolic activation, hormone behavior, and transcription and translation activation. This review will provide more comprehensive insights into the molecular mechanisms of seed germination. PMID:25597791

  14. Evolution of nutrient ingredients in tartary buckwheat seeds during germination.

    PubMed

    Yiming, Zhou; Hong, Wang; Linlin, Cui; Xiaoli, Zhou; Wen, Tang; Xinli, Song

    2015-11-01

    Evolution of nutrient components and the antioxidative activity of seed sprouts of tartary buckwheat (Fagopyrum tataricum L. Gaertn) were investigated in the course of germination. Results showed that the contents of total flavonoids increased with germination time and leveled off after the third germination day with the changing trend of rutin and quercetin opposite to each other. The decrease of total protein and total sugar contents in the germinated seeds was accompanied respectively by an increase of amino acid and reducing sugar contents. The contents of vitamin C (Vc) and B1(V(B1)) exhibited a minimum with no appreciable changes found for vitamin B(2) (V(B2)) and B(6) (V(B6)). The contents of total chlorophyll, chlorophyll A and B all exhibited a maximum on the fifth germination day. The contents of fatty acids had no regular changing trend with germination time. The free radical-scavenging activities of the seeds increased with germination time and were caused by an increase in their antioxidative activity. PMID:25976817

  15. Limited period of graviresponsiveness in germinating spores of Ceratopteris richardii

    NASA Technical Reports Server (NTRS)

    Edwards, E. S.; Roux, S. J.

    1994-01-01

    Rhizoids of the fern Ceratopteris richardii Brogn. usually emerge 40 h after germination is initiated by light, and more than 90% of them emerge growing in a downward direction. However, when the spores are germinated on a clinostat, the emerging rhizoids show no preferential orientation. This indicates that under normal 1 g conditions the initial growth direction of rhizoids can be oriented by gravity. If the orientation of the spores is changed 3 h or less after the start of germination, the growth direction of most emerging rhizoids becomes downward relative to the new orientation. However, if the orientation of the spores is changed by 180 degrees 8 h or more after germination is initiated by light, most rhizoids emerge growing upward; i.e., the same direction as if there had been no orientation change. Emerged rhizoids also do not change their direction of growth if their orientation is changed. These results indicate that the growth direction of emerging rhizoids is set by gravity prior to actual emergence, and that the time of full orientation responsiveness is limited to a period ranging from the initiation of germination to about 3-4 h after the start of germination. There is a gravity-oriented nuclear movement beginning at about 13 h after germination, and this movement appears to predict the initial growth direction of rhizoids.

  16. Proteomic analyses of apoplastic proteins from germinating Arabidopsis thaliana pollen

    PubMed Central

    Ge, Weina; Song, Yun; Zhang, Cuijun; Zhang, Yafang; Burlingame, Alma L.; Guo, Yi

    2011-01-01

    Pollen grains play important roles in the reproductive processes of flowering plants. The roles of apoplastic proteins in pollen germination and in pollen tube growth are comparatively less well understood. To investigate the functions of apoplastic proteins in pollen germination, the global apoplastic proteins of mature and germinated Arabidopsis thaliana pollen grains were prepared for differential analyses by using 2-dimensional fluorescence difference gel electrophoresis (2-D DIGE) saturation labeling techniques. One hundred and three proteins differentially expressed (p value ≤ 0.01) in pollen germinated for 6h compare with un-germination mature pollen, and 98 spots, which represented 71 proteins, were identified by LC-MS/MS. By bioinformatics analysis, 50 proteins were identified as secreted proteins. These proteins were mainly involved in cell wall modification and remodeling, protein metabolism and signal transduction. Three of the differentially expressed proteins were randomly selected to determine their subcellular localizations by transiently expressing YFP fusion proteins. The results of subcellular localization were identical with the bioinformatics prediction. Based on these data, we proposed a model for apoplastic proteins functioning in pollen germination and pollen tube growth. These results will lead to a better understanding of the mechanisms of pollen germination and pollen tube growth. PMID:21798377

  17. Proteomic insights into seed germination in response to environmental factors.

    PubMed

    Tan, Longyan; Chen, Sixue; Wang, Tai; Dai, Shaojun

    2013-06-01

    Seed germination is a critical process in the life cycle of higher plants. During germination, the imbibed mature seed is highly sensitive to different environmental factors.However, knowledge about the molecular and physiological mechanisms underlying the environmental effects on germination has been lacking. Recent proteomic work has provided invaluable insight into the molecular processes in germinating seeds of Arabidopsis, rice (Oryza sativa), soybean (Glycine max), barley (Hordeum vulgare), maize (Zeamays), tea (Camellia sinensis), European beech (Fagus sylvatica), and Norway maple (Acer platanoides) under different treatments including metal ions (e.g. copper and cadmium), drought, low temperature, hormones, and chemicals (gibberellic acid, abscisic acid, salicylic acid, and α-amanitin), as well as Fusarium graminearum infection. A total of 561 environmental factor-responsive proteins have been identified with various expression patterns in germinating seeds. The data highlight diverse regulatory and metabolic mechanisms upon seed germination, including induction of environmental factor-responsive signaling pathways, seed storage reserve mobilization and utilization, enhancement of DNA repair and modification, regulation of gene expression and protein synthesis, modulation of cell structure, and cell defense. In this review, we summarize the interesting findings and discuss the relevance and significance for our understanding of environmental regulation of seed germination. PMID:23986916

  18. Involvement of Alternative Splicing in Barley Seed Germination

    PubMed Central

    Zhang, Qisen; Zhang, Xiaoqi; Wang, Songbo; Tan, Cong; Zhou, Gaofeng; Li, Chengdao

    2016-01-01

    Seed germination activates many new biological processes including DNA, membrane and mitochondrial repairs and requires active protein synthesis and sufficient energy supply. Alternative splicing (AS) regulates many cellular processes including cell differentiation and environmental adaptations. However, limited information is available on the regulation of seed germination at post-transcriptional levels. We have conducted RNA-sequencing experiments to dissect AS events in barley seed germination. We identified between 552 and 669 common AS transcripts in germinating barley embryos from four barley varieties (Hordeum vulgare L. Bass, Baudin, Harrington and Stirling). Alternative 3’ splicing (34%-45%), intron retention (32%-34%) and alternative 5’ splicing (16%-21%) were three major AS events in germinating embryos. The AS transcripts were predominantly mapped onto ribosome, RNA transport machineries, spliceosome, plant hormone signal transduction, glycolysis, sugar and carbon metabolism pathways. Transcripts of these genes were also very abundant in the early stage of seed germination. Correlation analysis of gene expression showed that AS hormone responsive transcripts could also be co-expressed with genes responsible for protein biosynthesis and sugar metabolisms. Our RNA-sequencing data revealed that AS could play important roles in barley seed germination. PMID:27031341

  19. A shotgun phosphoproteomics analysis of embryos in germinated maize seeds.

    PubMed

    Lu, Tian-Cong; Meng, Ling-Bo; Yang, Chuan-Ping; Liu, Gui-Feng; Liu, Guan-Jun; Ma, Wei; Wang, Bai-Chen

    2008-11-01

    To better understand the role that reversible protein phosphorylation plays in seed germination, we initiated a phosphoproteomic investigation of embryos of germinated maize seeds. A total of 776 proteins including 39 kinases, 16 phosphatases, and 33 phosphoproteins containing 36 precise in vivo phosphorylation sites were identified. All the phosphorylation sites identified, with the exception of the phosphorylation site on HSP22, have not been reported previously (Lund et al. in J Biol Chem, 276, 29924-29929, 2001). Assayed with QRT-PCR, the transcripts of ten kinase genes were found to be dramatically up-regulated during seed germination and those of four phosphatase genes were up-regulated after germination, which indicated that reversible protein phosphorylation occurred and complex regulating networks were activated during this period. At least one-third of these phosphoproteins are key components involved in biological processes which relate to seed germination, such as DNA repair, gene transcription, RNA splicing and protein translation, suggesting that protein phosphorylation plays an important role in seed germination. As far as we know, this is the first phosphoproteomic study on a monocot and it will lay a solid foundation for further study of the molecular mechanisms of seed germination and seedling development. PMID:18726113

  20. Thermoinhibition uncovers a role for strigolactones in Arabidopsis seed germination.

    PubMed

    Toh, Shigeo; Kamiya, Yuji; Kawakami, Naoto; Nambara, Eiji; McCourt, Peter; Tsuchiya, Yuichiro

    2012-01-01

    Strigolactones are host factors that stimulate seed germination of parasitic plant species such as Striga and Orobanche. This hormone is also important in shoot branching architecture and photomorphogenic development. Strigolactone biosynthetic and signaling mutants in model systems, unlike parasitic plants, only show seed germination phenotypes under limited growth condition. To understand the roles of strigolactones in seed germination, it is necessary to develop a tractable experimental system using model plants such as Arabidopsis. Here, we report that thermoinhibition, which involves exposing seeds to high temperatures, uncovers a clear role for strigolactones in promoting Arabidopsis seed germination. Both strigolactone biosynthetic and signaling mutants showed increased sensitivity to seed thermoinhibition. The synthetic strigolactone GR24 rescued germination of thermoinbibited biosynthetic mutant seeds but not a signaling mutant. Hormone analysis revealed that strigolactones alleviate thermoinhibition by modulating levels of the two plant hormones, GA and ABA. We also showed that GR24 was able to counteract secondary dormancy in Arabidopsis ecotype Columbia (Col) and Cape Verde island (Cvi). Systematic hormone analysis of germinating Striga helmonthica seeds suggested a common mechanism between the parasitic and non-parasitic seeds with respect to how hormones regulate germination. Thus, our simple assay system using Arabidopsis thermoinhibition allows comparisons to determine similarities and differences between parasitic plants and model experimental systems for the use of strigolactones. PMID:22173099

  1. The effects of smoke derivatives on in vitro seed germination and development of the leopard orchid Ansellia africana.

    PubMed

    Papenfus, H B; Naidoo, D; Pošta, M; Finnie, J F; Van Staden, J

    2016-03-01

    Plant-derived smoke and smoke-isolated compounds stimulate germination in seeds from over 80 genera. It has also been reported that smoke affects overall plant vigour and has a stimulatory effect on pollen growth. The effect of smoke on orchid seeds, however, has not been assessed. In South Africa, orchid seeds from several genera may be exposed to smoke when they are released from their seedpods. It is therefore possible that smoke may affect their germination and growth. Therefore, the effects of smoke [applied as smoke-water (SW)] and two smoke-derived compounds, karrikinolide (KAR1 ) and trimethylbutenolide (TMB), were investigated on the germination and growth of orchid seeds in vitro. The effect of SW, KAR1 and TMB were investigated on the endangered epiphytic orchid, Ansellia africana, which is indigenous to tropical areas of Africa. Smoke-water, KAR1 and TMB were infused in half-strength MS medium. The number of germinated seeds and number of seeds and protocorm bodies to reach predetermined developmental stages were recorded on a weekly basis using a dissecting microscope for a 13-week period. Infusing SW 1:250 (v:v) into half-strength MS medium significantly increased the germination rate index (GRI) and the development rate index (DRI) of the A. africana seeds. All the SW treatments significantly increased the number of large protocorm bodies at the final stage of development. Infusing KAR1 into the growing medium had no significant effect on germination or development of the seeds. The TMB treatment, however, significantly reduced the GRI and DRI of A. africana seeds. PMID:26206372

  2. Germination and seedling establishment in orchids: a complex of requirements

    PubMed Central

    Rasmussen, Hanne N.; Dixon, Kingsley W.; Jersáková, Jana; Těšitelová, Tamara

    2015-01-01

    Background Seedling recruitment is essential to the sustainability of any plant population. Due to the minute nature of seeds and early-stage seedlings, orchid germination in situ was for a long time practically impossible to observe, creating an obstacle towards understanding seedling site requirements and fluctuations in orchid populations. The introduction of seed packet techniques for sowing and retrieval in natural sites has brought with it important insights, but many aspects of orchid seed and germination biology remain largely unexplored. Key Considerations The germination niche for orchids is extremely complex, because it is defined by requirements not only for seed lodging and germination, but also for presence of a fungal host and its substrate. A mycobiont that the seedling can parasitize is considered an essential element, and a great diversity of Basidiomycota and Ascomycota have now been identified for their role in orchid seed germination, with fungi identifiable as imperfect Rhizoctonia species predominating. Specificity patterns vary from orchid species employing a single fungal lineage to species associating individually with a limited selection of distantly related fungi. A suitable organic carbon source for the mycobiont constitutes another key requirement. Orchid germination also relies on factors that generally influence the success of plant seeds, both abiotic, such as light/shade, moisture, substrate chemistry and texture, and biotic, such as competitors and antagonists. Complexity is furthermore increased when these factors influence seeds/seedling, fungi and fungal substrate differentially. Conclusions A better understanding of germination and seedling establishment is needed for conservation of orchid populations. Due to the obligate association with a mycobiont, the germination niches in orchid species are extremely complex and varied. Microsites suitable for germination can be small and transient, and direct observation is difficult

  3. Germination rate is the significant characteristic determining coconut palm diversity

    PubMed Central

    Harries, Hugh C.

    2012-01-01

    Rationale This review comes at a time when in vitro embryo culture techniques are being adopted for the safe exchange and cryo-conservation of coconut germplasm. In due course, laboratory procedures may replace the options that exist among standard commercial nursery germination techniques. These, in their turn, have supplanted traditional methods that are now forgotten or misunderstood. Knowledge of all germination options should help to ensure the safe regeneration of conserved material. Scope This review outlines the many options for commercial propagation, recognizes the full significance of one particular traditional method and suggests that the diversity of modern cultivated coconut varieties has arisen because natural selection and domestic selection were associated with different rates of germination and other morphologically recognizable phenotypic characteristics. The review takes into account both the recalcitrant and the viviparous nature of the coconut. The ripe fruits that fall but do not germinate immediately and lose viability if dried for storage are contrasted with the bunches of fruit retained in the crown of the palm that may, in certain circumstances, germinate to produce seedlings high above ground level. Significance Slow-germinating and quick-germinating coconuts have different patterns of distribution. The former predominate on tropical islands and coastlines that could be reached by floating when natural dispersal originally spread coconuts widely—but only where tides and currents were favourable—and then only to sea-level locations. Human settlers disseminated the domestic types even more widely—to otherwise inaccessible coastal sites not reached by floating—and particularly to inland and upland locations on large islands and continental land masses. This review suggests four regions where diversity has been determined by germination rates. Although recent DNA studies support these distinctions, further analyses of genetic markers

  4. The effects of whole-body vibration on the Wingate test for anaerobic power when applying individualized frequencies.

    PubMed

    Surowiec, Rachel K; Wang, Henry; Nagelkirk, Paul R; Frame, Jeffrey W; Dickin, D Clark

    2014-07-01

    Recently, individualized frequency (I-Freq) has been introduced with the notion that athletes may elicit a greater reflex response at differing levels (Hz) of vibration. The aim of the study was to evaluate acute whole-body vibration as a feasible intervention to increase power in trained cyclists and evaluate the efficacy of using I-Freq as an alternative to 30Hz, a common frequency seen in the literature. Twelve highly trained, competitive male cyclists (age, 29.9 ± 10.0 years; body height, 175.4 ± 7.8 cm; body mass, 77.3 ± 13.9 kg) participated in the study. A Wingate test for anaerobic power was administered on 3 occasions: following a control of no vibration, 30 Hz, or I-freq. Measures of peak power, average power (AP), and the rate of fatigue were recorded and compared with the vibration conditions using separate repeated measures analysis of variance. Peak power, AP, and the rate of fatigue were not significantly impacted by either the 30 Hz or I-Freq vibration interventions (p > 0.05). Given the trained status of the individuals in this study, the ability to elicit an acute response may have been muted. Future studies should further refine the vibration parameters used and assess changes in untrained or recreationally trained populations. PMID:24378660

  5. Inhibition of Orobanche crenata seed germination and radicle growth by allelochemicals identified in cereals.

    PubMed

    Fernández-Aparicio, Mónica; Cimmino, Alessio; Evidente, Antonio; Rubiales, Diego

    2013-10-16

    Orobanche crenata is a parasitic weed that causes severe yield losses in important grain and forage legume crops. Cereals have been reported to inhibit O. crenata parasitism when grown intercropped with susceptible legumes, but the responsible metabolites have not been identified. A number of metabolites have been reported in cereals that have allelopathic properties against weeds, pests, and pathogens. We tested the effect of several allelochemicals identified in cereals on O. crenata seed germination and radicle development. We found that 2-benzoxazolinone, its derivative 6-chloroacetyl-2-benzoxazolinone, and scopoletin significantly inhibited O. crenata seed germination. Benzoxazolinones, l-tryptophan, and coumalic acid caused the stronger inhibition of radicle growth. Also, other metabolites reduced radicle length, this inhibition being dose-dependent. Only scopoletin caused cell necrotic-like darkening in the young radicles. Prospects for their application to parasitic weed management are discussed. PMID:24044614

  6. Effects of high voltage nanosecond pulsed plasma and micro DBD plasma on seed germination, growth development and physiological activities in spinach.

    PubMed

    Ji, Sang-Hye; Choi, Ki-Hong; Pengkit, Anchalee; Im, Jun Sup; Kim, Ju Sung; Kim, Yong Hee; Park, Yeunsoo; Hong, Eun Jeong; Jung, Sun Kyung; Choi, Eun-Ha; Park, Gyungsoon

    2016-09-01

    In this study, we analyzed seed germination, seedling growth, and physiological aspects after treatment with high voltage nanosecond pulsed plasma and micro DBD plasma in spinach (Spinacia oleracea L.), a green leafy vegetable known to have low germination rate. Both germination and dry weight of seedlings increased after high voltage pulse shots were applied to spinach seeds. However seeds treated with many shots (10 shots) showed a decrease in germination rate and seedling growth. Seeds treated with air DBD plasma exhibited slightly higher germination and subsequent seedling growth than those treated with N2 plasma. Seed surface was degenerated after treated with high voltage pulsed plasma and micro DBD plasma but no significant difference in the degree of degeneration was observed among micro DBD plasma treatment time. Level of GA3 hormone and mRNA expression of an amylolytic enzyme-related gene in seeds were elevated 1 day after treatment with high voltage pulsed plasma. The relative amount of chlorophyll and total polyphenols in spinach seedlings grown from seeds treated with air DBD plasma was increased in 30 s, 1 min, and 3 min treatments. Taken together, our results suggest a possibility that plasma can enhance seed germination by triggering biochemical processes in seeds. PMID:26944552

  7. Germination and growth of wheat in simulated Martian atmospheres

    NASA Technical Reports Server (NTRS)

    Schwartzkopf, Steven H.; Mancinelli, Rocco L.

    1991-01-01

    One design for a manned Mars base incorporates a bioregenerative life support system based upon growing higher plants at a low atmospheric pressure in a greenhouse on the Martian surface. To determine the concept's feasibility, the germination and initial growth of wheat (Triticum aestivum) was evaluated at low atmospheric pressures in simulated Martian atmosphere (SMA) and in SMA supplemented with oxygen. Total atmospheric pressures ranged from 10 to 1013 mb. No seeds germinated in pure SMA, regardless of atmospheric pressure. In SMA plus oxygen at 60 mb total pressure, germination and growth occurred but were lower than in the earth atmosphere controls.

  8. Effect of synthetic detergents on germination of fern spores

    SciTech Connect

    Devi, Y.; Devi, S.

    1986-12-01

    Synthetic detergents constitute one of the most important water pollutants by contaminating the lakes and rivers through domestic and industrial use. Considerable information is now available for the adverse effects of detergents an aquatic fauna including fish, algae, and higher aquatic plants. Marked inhibition of germination in orchids and brinjals and of seedlings growth in raddish suggest that rapidly growing systems could be sensitive to detergent polluted water. The present study of the effect of linear alkyl benzene sulphonate on germination of the spores of a fern, Diplazium esculentum aims at the understanding of the effects of water pollution on pteridophytes and the development of spore germination assay for phytoxicity evaluation.

  9. Germination and growth of wheat in simulated Martian atmospheres

    NASA Astrophysics Data System (ADS)

    Schwartzkopf, Steven H.; Mancinelli, Rocco L.

    One design for a manned Mars base incorporates a bioregenerative life support system based upon growing higher plants at a low atmospheric pressure in a greenhouse on the Martian surface. To determine the concept's feasibility, the germination and initial growth of wheat ( Triticum aestivum) was evaluated at low atmospheric pressures in simulated Martian atmosphere (SMA) and in SMA supplemented with oxygen. Total atmospheric pressures ranged from 10 to 1013 mb. No seeds germinated in pure SMA, regardless of atmospheric pressure. In SMA plus oxygen at 60 mb total pressure, germination and growth occurred but were lower than in the Earth atmosphere controls.

  10. Elemental variations in the germinating fungus Phytophthora palmivora

    NASA Astrophysics Data System (ADS)

    Mazzolini, A. P.; Grant, B. R.; Sealock, R. M.; Legge, G. J. F.

    1991-03-01

    We have measured the elemental variations between zoospores and germinating cystospores of the fungus Phytophthora palmivora, using a scanning proton microprobe. Averaged over a number of individual cells, our results indicate that the level of Ca is much lower in germinating cystospores than in zoospores. The levels of S, Cl, and Zn also appear to be lower, and the level of K appears to be higher. The spatial distribution of elements within the germinating cystospore is very similar for P, S, Cl, K, Mn, Fe, and Cu, but significantly different for Ca and Zn.

  11. Development of a Test System To Apply Virus-Containing Particles to Filtering Facepiece Respirators for the Evaluation of Decontamination Procedures▿

    PubMed Central

    Fisher, Edward; Rengasamy, Samy; Viscusi, Dennis; Vo, Evanly; Shaffer, Ronald

    2009-01-01

    A chamber to apply aerosolized virus-containing particles to air-permeable substrates (coupons) was constructed and validated as part of a method to assess the virucidal efficacy of decontamination procedures for filtering facepiece respirators. Coliphage MS2 was used as a surrogate for pathogenic viruses for confirmation of the efficacy of the bioaerosol respirator test system. The distribution of virus applied onto and within the coupons was characterized, and the repeatability of applying a targeted virus load was examined. The average viable virus loaded onto 90 coupons over the course of 5 days was found to be 5.09 ± 0.19 log10 PFU/coupon (relative standard deviation, 4%). To determine the ability to differentiate the effectiveness of disinfecting procedures with different levels of performance, sodium hypochlorite and steam treatments were tested in experiments by varying the dose and time, respectively. The role of protective factors was assessed by aerosolizing the virus with various concentrations of the aerosol-generating medium. A sodium hypochlorite (bleach) concentration of 0.6% and steam treatments of 45 s and longer resulted in log reductions (>4 logs) which reached the detection limits for both levels of protective factors. Organic matter (ATCC medium 271) as a protective factor afforded some protection to the virus in the sodium hypochlorite experiments but was not a factor in the steam experiments. The evaluation of the bioaerosol respirator test system demonstrated a repeatable method for applying a targeted viral load onto respirator coupons and provided insight into the properties of aerosols that are of importance to the development of disinfection assays for air-permeable materials. PMID:19139225

  12. Trypsinlike enzymes from dormant and germinated spores of Bacillus cereus T and their possible involvement in germination.

    PubMed Central

    Boschwitz, H; Halvorson, H O; Keynan, A; Milner, Y

    1985-01-01

    Trypsin-like enzymes were studied in dormant, activated, and germinated spores of Bacillus cereus T. Dormant spores contained two heat-labile enzyme activities. One was extractable with 2 M KCl and hydrolyzed azo-albumin. The second, a trypsinlike activity, was not extractable with 2 M KCl and hydrolyzed benzoyl-L-arginine-p-nitroanilide. Because of their heat instability, these two enzyme activities are probably not involved in the germination of heat-activated spores. Upon germination of heat-treated spores, a trypsinlike protease which was not detected in intact dormant spores was activated or exposed. This enzyme, when measured in intact germinated spores, hydrolyzed benzoyl-DL-arginine-p-nitroanilide but not azo-albumin and was inhibited in situ by sulfhydryl-blocking reagents such as p-chloromercuribenzoic acid and Hg2+. There was a correlation between the inhibition of germination and enzymatic activity by sulfhydryl-blocking reagents. The enzyme was also inhibited by leupeptin, tosyl-L-lysine chromoethyl ketone, and tosyl-L-arginine methyl ester. Good correlation existed between the inhibition of germination and enzymatic activity by these agents. Electron micrographs showed that in the presence of trypsin inhibitors, the spores did not lose their cortex. The protein extracts of the inhibited spores formed a somewhat different electrophoretic pattern in sodium dodecyl sulfate-polyacrylamide gel electrophoresis than the protein extracts of dormant or germinated spores. Images PMID:3930468

  13. Spore germination based assay for monitoring antibiotic residues in milk at dairy farm.

    PubMed

    Kumar, Naresh; Raghu, Hirikyathanahalli Vishweswaraiah; Kumar, Abhishek; Haldar, Lopamudra; Khan, Alia; Rane, Sharmila; Malik, Ravinder Kumar

    2012-07-01

    Spore germination based assay involves the transformation of dormant spores of Bacillus stearothermophilus 953 into active vegetative cells. The inhibition of germination process specifically in presence of antibiotic residues was used as a novel approach for monitoring target contaminants in milk. The indicator organism i.e., B. stearothermophilus 953 was initially allowed to sporulate by seeding in sporulation medium and incubating at 55 °C for 18 ± 2 h. The spores exhibited a typical chain behavior as revealed through phase contrast microscopy. The minimal medium inoculated with activated spores was incubated at 64 °C for 2-3 h for germination and outgrowth in presence of specific germinant mixture containing dextrose, whey powder and skimmed milk powder added in specific ratio along with reconstituted milk as negative control and test milk samples. The change in color of the medium from purple to yellow was used as criteria for detection of antibiotic residues in milk. The efficiency of the developed assay was evaluated through a surveillance study on 228 samples of raw, pasteurized and dried milks and results were compared with AOAC approved microbial receptor assay. The presence of antibiotic level was 10.08 % at Codex maximum residual limit having false positive result only in 0.43 % of the samples. The results of the present investigation suggest that developed spore based assay can be a practical solution to dairy industry for its application at farm level, milk processing units, independent testing and R & D centres in order to comply with the legal requirements set by Codex. PMID:22806162

  14. BP-ANN for Fitting the Temperature-Germination Model and Its Application in Predicting Sowing Time and Region for Bermudagrass

    PubMed Central

    Pi, Erxu; Mantri, Nitin; Ngai, Sai Ming; Lu, Hongfei; Du, Liqun

    2013-01-01

    Temperature is one of the most significant environmental factors that affects germination of grass seeds. Reliable prediction of the optimal temperature for seed germination is crucial for determining the suitable regions and favorable sowing timing for turf grass cultivation. In this study, a back-propagation-artificial-neural-network-aided dual quintic equation (BP-ANN-QE) model was developed to improve the prediction of the optimal temperature for seed germination. This BP-ANN-QE model was used to determine optimal sowing times and suitable regions for three Cynodon dactylon cultivars (C. dactylon, ‘Savannah’ and ‘Princess VII’). Prediction of the optimal temperature for these seeds was based on comprehensive germination tests using 36 day/night (high/low) temperature regimes (both ranging from 5/5 to 40/40°C with 5°C increments). Seed germination data from these temperature regimes were used to construct temperature-germination correlation models for estimating germination percentage with confidence intervals. Our tests revealed that the optimal high/low temperature regimes required for all the three bermudagrass cultivars are 30/5, 30/10, 35/5, 35/10, 35/15, 35/20, 40/15 and 40/20°C; constant temperatures ranging from 5 to 40°C inhibited the germination of all three cultivars. While comparing different simulating methods, including DQEM, Bisquare ANN-QE, and BP-ANN-QE in establishing temperature based germination percentage rules, we found that the R2 values of germination prediction function could be significantly improved from about 0.6940–0.8177 (DQEM approach) to 0.9439–0.9813 (BP-ANN-QE). These results indicated that our BP-ANN-QE model has better performance than the rests of the compared models. Furthermore, data of the national temperature grids generated from monthly-average temperature for 25 years were fit into these functions and we were able to map the germination percentage of these C. dactylon cultivars in the national scale of

  15. Does nitrogen saturation theory apply to unpolluted temperate forests? A test along a forest soil nitrogen gradient in Oregon

    NASA Astrophysics Data System (ADS)

    Perakis, S. S.; Sinkhorn, E. R.

    2011-12-01

    Natural gradients of soil nitrogen (N) can be used to evaluate the consequences of long-term ecosystem N enrichment, and to test the applicability of N saturation theory as a general framework for understanding ecosystem N dynamics. Temperate forest soils of the Oregon Coast Range experience low rates of atmospheric N deposition, yet display among the highest soil N accumulations ever reported worldwide. We measured plant and soil (0-1m) N stocks and natural abundance delta15N, plant production, N uptake and return in litterfall, soil gross and net N mineralization rates, and hydrologic N losses of nine Douglas-fir forests growing across an exceptionally wide soil N gradient in the Oregon Coast Range. Ecosystem N content ranged from 8,788 to 22,667 kg N/ha across sites, with highest N accumulations near the coast, and 96-98% of total ecosystem N residing in mineral soil. Ecosystem delta15N displayed a curvilinear relationship with ecosystem N content that reflected competing influences of N input from biological fixation at low-N sites and fractionating N losses at high-N sites. Simulation modeling of ecosystem N and delta15N mass balance suggest that cycles of wildfire can promote unusually high natural N accumulation by fostering early successional biological nitrogen fixation. Surface mineral soil (0 - 10 cm) N concentrations were tightly correlated to total soil N stocks to 1 m depth, and in contrast to predictions of N saturation theory, were linearly related to 10-fold variation in net N mineralization from 8 - 82 kg N/ha-yr. Net N mineralization was unrelated to soil C:N, soil texture, precipitation and temperature differences among sites. Net nitrification accounted for < 20% of net N mineralization at low N sites, increasing to 85 - 100% of net N mineralization at intermediate and high N sites, and was associated with soil pH decline from 5.8 to 4.1 across sites. The ratio of net:gross N mineralization and nitrification increased along the gradient

  16. Impact of dyeing industry effluent on germination and growth of pea (Pisum sativum).

    PubMed

    Malaviya, Piyush; Hali, Rajesh; Sharma, Neeru

    2012-11-01

    Dye industry effluent was analyzed for physico-chemical characteristics and its impact on germination and growth behaviour of Pea (Pisum sativum). The 100% effluent showed high pH (10.3) and TDS (1088 mg l(-1)). The germination parameters included percent germination, delay index, speed of germination, peak value and germination period while growth parameters comprised of root and shoot length, root and shootweight, root-shoot ratio and number of stipules. The study showed the maximum values of positive germination parameters viz. speed of germination (7.85), peak value (3.28), germination index (123.87) and all growth parameters at 20% effluent concentration while the values of negative germination parameters viz. delay index (-0.14) and percent inhibition (-8.34) were found to be minimum at 20% effluent concentration. The study demonstrated that at lower concentrations the dyeing industry effluent caused a positive impact on germination and growth of Pisum sativum. PMID:23741804

  17. Highly Resolved Intravital Striped-illumination Microscopy of Germinal Centers

    PubMed Central

    Andresen, Volker; Sporbert, Anje

    2014-01-01

    Monitoring cellular communication by intravital deep-tissue multi-photon microscopy is the key for understanding the fate of immune cells within thick tissue samples and organs in health and disease. By controlling the scanning pattern in multi-photon microscopy and applying appropriate numerical algorithms, we developed a striped-illumination approach, which enabled us to achieve 3-fold better axial resolution and improved signal-to-noise ratio, i.e. contrast, in more than 100 µm tissue depth within highly scattering tissue of lymphoid organs as compared to standard multi-photon microscopy. The acquisition speed as well as photobleaching and photodamage effects were similar to standard photo-multiplier-based technique, whereas the imaging depth was slightly lower due to the use of field detectors. By using the striped-illumination approach, we are able to observe the dynamics of immune complex deposits on secondary follicular dendritic cells – on the level of a few protein molecules in germinal centers. PMID:24748007

  18. Proteomics of seed development, desiccation tolerance, germination and vigor.

    PubMed

    Wang, Wei-Qing; Liu, Shu-Jun; Song, Song-Quan; Møller, Ian Max

    2015-01-01

    Proteomics, the large-scale study of the total complement of proteins in a given sample, has been applied to all aspects of seed biology mainly using model species such as Arabidopsis or important agricultural crops such as corn and rice. Proteins extracted from the sample have typically been separated and quantified by 2-dimensional polyacrylamide gel electrophoresis followed by liquid chromatography and mass spectrometry to identify the proteins in the gel spots. In this way, qualitative and quantitative changes in the proteome during seed development, desiccation tolerance, germination, dormancy release, vigor alteration and responses to environmental factors have all been studied. Many proteins or biological processes potentially important for each seed process have been highlighted by these studies, which greatly expands our knowledge of seed biology. Proteins that have been identified to be particularly important for at least two of the seed processes are involved in detoxification of reactive oxygen species, the cytoskeleton, glycolysis, protein biosynthesis, post-translational modifications, methionine metabolism, and late embryogenesis-abundant (LEA) proteins. It will be useful for molecular biologists and molecular plant breeders to identify and study genes encoding particularly interesting target proteins with the aim to improve the yield, stress tolerance or other critical properties of our crop species. PMID:25461695

  19. Competition/colonization syndrome mediated by early germination in non-dispersing achenes in the heteromorphic species Crepis sancta

    PubMed Central

    Dubois, Jonathan; Cheptou, Pierre-Olivier

    2012-01-01

    Background and Aims The competition–colonization trade-off theory postulates that the competitive and colonizing abilities of organisms are negatively related; this trade-off has been proposed as a major force in the maintenance of diversity. In plants, the competition–colonization trade-off is often considered to result from variation in resource partitioning, thus generating heavy competitive (non-dispersing) seeds and light (dispersing) non-competitive seeds. Here, the possibility is explored that early germination provides a competitive advantage, thus mediating competitive interactions. Methods Using eight populations of the heterocarpic species Crepis sancta (Asteraceae), the possibility was tested that dispersing and non-dispersing achenes differ in germination timing, and the impact of early germination on individual fitness components was analysed in the context of intraspecific competition. To evaluate whether seed reserve varies among achene types, endosperm size was also measured by analysing photographs of cross-sections taken under a binocular microscope. Key Results and Conclusions The results show that non-dispersing achenes germinated 4 d earlier (on average) than dispersing achenes. It is also shown that early germination provides a positive advantage for the survival and final biomass of individuals, a pattern that was consistent over the eight populations and independent of achene type. Dispersing and non-dispersing achenes did not differ in terms of seed reserve (endosperm size). It is proposed that germination phenology may mediate the competition–colonization trade-off in Crepis sancta and the evolutionary significance of this phenomenon is discussed. PMID:23022677

  20. Comparison of germination responses of Anigozanthos flavidus (Haemodoraceae), Gyrostemon racemiger and Gyrostemon ramulosus (Gyrostemonaceae) to smoke-water and the smoke-derived compounds karrikinolide (KAR1) and glyceronitrile

    PubMed Central

    Downes, Katherine S.; Light, Marnie E.; Pošta, Martin; Kohout, Ladislav; van Staden, Johannes

    2013-01-01

    Background and Aims A major germination-promoting chemical in smoke-water is 3-methyl-2H-furo[2,3-c]pyran-2-one (karrikinolide, KAR1). However, not all species that germinate in response to smoke-water are responsive to KAR1, such as Tersonia cyathiflora (Gyrostemonaceae). In this study, a test was made of whether two Gyrostemon species (Gyrostemonaceae) that have previously been shown to respond to smoke-water, respond to KAR1. If not, then the smoke-derived chemical that stimulates germination of these species is currently unknown. Recently, glyceronitrile was isolated from smoke-water and promoted the germination of certain Anigozanthos species (Haemodoraceae). Whether this chemical promotes Gyrostemon racemiger germination is also examined. Furthermore, an investigation was carried out into whether these species germinate in response to smoke-water derived from burning cellulose alone. Methods Gyrostemon racemiger and G. ramulosus seeds were buried after collection and retrieved in autumn the following year when dormancy was alleviated and seeds had become responsive to smoke-water. Anigozanthos flavidus seeds were after-ripened at 35 °C to alleviate dormancy. Gyrostemon and Anigozanthos seeds were then tested with ‘Seed Starter’ smoke-water, KAR1, glyceronitrile and cellulose-derived smoke-water. Key Results Although Gyrostemon racemiger, G. ramulosus and A. flavidus were all stimulated to germinate by ‘Seed Starter’ smoke-water, none of these species responded to KAR1. Gyrostemon racemiger germination was not promoted by glyceronitrile. This is in contrast to A. flavidus, where glyceronitrile, at concentrations of 1–500 µm, promoted germination, although seedling growth was inhibited at ≥400 µm. Maximum A. flavidus germination occurred at glyceronitrile concentrations of 25–300 µm. Some Gyrostemon germination was promoted by cellulose-derived smoke-water. Conclusions KAR1 and glyceronitrile, chemicals in smoke-water that are known to

  1. Germination Characteristics Of Some Great Basin Native Annual Forb Species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Great Basin native plant communities are being replaced by the annual invasive cheatgrass (Bromus tectorum). Cheatgrass exhibits a germination syndrome that is characteristic of facultative winter annuals. Although perennials dominate these communities, native annuals are present in many sites. Germ...

  2. Strigolactones as Germination Stimulants for Root Parasitic Plants

    PubMed Central

    Yoneyama, Koichi; Awad, Ayman A.; Xie, Xiaonan; Yoneyama, Kaori; Takeuchi, Yasutomo

    2010-01-01

    Witchweeds (Striga spp.) and broomrapes (Orobanche and Phelipanche spp.) are the two most devastating root parasitic plants belonging to the family Orobanchaceae and are causing enormous crop losses throughout the world. Seeds of these root parasites will not germinate unless they are exposed to chemical stimuli, ‘germination stimulants’ produced by and released from plant roots. Most of the germination stimulants identified so far are strigolactones (SLs), which also function as host recognition signals for arbuscular mycorrhizal fungi and a novel class of plant hormones inhibiting shoot branching. In this review, we focus on SLs as germination stimulants for root parasitic plants. In addition, we discuss how quantitative and qualitative differences in SL exudation among sorghum cultivars influence their susceptibility to Striga. PMID:20403809

  3. Greenhouse germination and characterization of Synchytrium solstitiale resting spores

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Synchytrium solstitiale was evaluated for suitability in biological control of yellow starthisle (YST). A protocol was developed for maintenance of S. solstitiale in galled tissue under greenhouse conditions. Recently, protocol has been developed for germination of resting spores. Resting spores ...

  4. Germinated brown rice and its bio-functional compounds.

    PubMed

    Cho, Dong-Hwa; Lim, Seung-Taik

    2016-04-01

    Brown rice (BR) contains bran layers and embryo, where a variety of nutritional and biofunctional components, such as dietary fibers, γ-oryzanol, vitamins, and minerals, exist. However, BR is consumed less than white rice because it has an inferior eating texture when cooked. Germination is one of the techniques used to improve the texture of the cooked BR. In addition, it induces numerous changes in the composition and chemical structure of the bioactive components. Moreover, many studies reported that the germination could induce the formation of new bioactive compounds, such as gamma-aminobutyric acid (GABA). The consumption of germinated brown rice (GBR) is increasing in many Asian countries because of its improved eating quality and potential health-promoting functions. However, there is still a lack of studies on the compositional and functional changes of the bioactive components during germination. This review contains recent research findings, especially on the bioactive components in GBR. PMID:26593491

  5. Localization of Carboxypeptidase I in Germinating Barley Grain 1

    PubMed Central

    Ranki, Harri; Sopanen, Tuomas; Voutilainen, Raimo

    1990-01-01

    Activity measurements and Northern blot hybridizations were used to study the temporal and spatial expression of carboxypeptidase I in germinating grains of barley (Hordeum vulgare L. cv Himalaya). In the resting grain no carboxypeptidase I activity was found in the aleurone layer, scutellum, or starchy endosperm. During germination high levels of enzyme activity appeared in the scutellum and in the starchy endosperm but only low activity was found in the aleurone layer. No mRNA for carboxypeptidase I was observed in the resting grain. By day 1 of germination the mRNA appeared in the scutellum where its level remained high for several days. In contrast, little mRNA was observed in the aleurone layer. These results indicate that the scutellum plays an important role in the production of carboxypeptidase I in germinating barley grain. Images Figure 3 PMID:16667638

  6. Anaerobic conditions improve germination of a gibberellic acid deficient rice

    NASA Technical Reports Server (NTRS)

    Frantz, Jonathan M.; Bugbee, Bruce

    2002-01-01

    Dwarf plants are useful in research because multiple plants can be grown in a small area. Rice (Oryza sativa L.) is especially important since its relatively simple genome has recently been sequenced. We are characterizing a gibberellic acid (GA) mutant of rice (japonica cv 'Shiokari,' line N-71) that is extremely dwarf (20 cm tall). Unfortunately, this GA mutation is associated with poor germination (70%) under aerobic conditions. Neither exogenous GA nor a dormancy-breaking heat treatment improved germination. However, 95% germination was achieved by germinating the seeds anaerobically, either in a pure N2 environment or submerged in unstirred tap water. The anaerobic conditions appear to break a mild post-harvest dormancy in this rice cultivar. Copyright 2002 Crop Science Society of America.

  7. Alkaloid Changes in Tobacco Seeds during Germination 1

    PubMed Central

    Weeks, W. W.; Bush, L. P.

    1974-01-01

    Nicotine, nornicotine, anabasine, and anatabine, normally found in growing and mature tobacco (Nicotiana tabacum L.) plants, were extracted and quantified from mature tobacco seeds and young tobacco seedlings. The rate of net alkaloid disappearance and accumulation in tobacco seedlings was related to phases of germination. In general, the increased rate of germination associated with higher temperatures also increased the rate of initial loss of alkaloids and the subsequent rate of accumulation of alkaloids. Maximum alkaloid accumulation in 144-hour-old seedlings cultured with 10-hour day occurred at 27 C. Following an 8-hour photoinduction period, seeds germinated in darkness accumulated greater amounts of alkaloids than seeds exposed to light each day. Seeds germinated in darkness for 96 hours, following the 8-hour photoinduction period, and then exposed to light each day accumulated the greatest amounts of alkaloids. PMID:16658655

  8. Strigolactones as germination stimulants for root parasitic plants.

    PubMed

    Yoneyama, Koichi; Awad, Ayman A; Xie, Xiaonan; Yoneyama, Kaori; Takeuchi, Yasutomo

    2010-07-01

    Witchweeds (Striga spp.) and broomrapes (Orobanche and Phelipanche spp.) are the two most devastating root parasitic plants belonging to the family Orobanchaceae and are causing enormous crop losses throughout the world. Seeds of these root parasites will not germinate unless they are exposed to chemical stimuli, 'germination stimulants' produced by and released from plant roots. Most of the germination stimulants identified so far are strigolactones (SLs), which also function as host recognition signals for arbuscular mycorrhizal fungi and a novel class of plant hormones inhibiting shoot branching. In this review, we focus on SLs as germination stimulants for root parasitic plants. In addition, we discuss how quantitative and qualitative differences in SL exudation among sorghum cultivars influence their susceptibility to Striga. PMID:20403809

  9. Starch bioengineering affects cereal grain germination and seedling establishment

    PubMed Central

    Hebelstrup, Kim H.; Blennow, Andreas

    2014-01-01

    Cereal grain germination is central for plant early development, and efficient germination has a major role in crop propagation and malting. Endosperm starch is the prime energy reserve in germination and seedling establishment. In this study, it was hypothesized that optimized starch granule structure, and not only the endosperm starch content per se, is important for germination and seedling establishment. For that purpose, wild-type (WT), and specifically engineered degradable hyperphosphorylated (HP) starch and more resistant amylose-only (AO) starch barley lines were used. The transgenics showed no severe phenotypes and the WT and HP lines degraded the starch similarly, having 30% residual starch after 12 d of germination. However, the AO line showed significant resistance to degradation, having 57% residual starch. Interestingly, protein and β-glucan (BG) degradation was stimulated for both HP and AO lines as compared with the WT. At late seedling establishment stages, specific sugars were rapidly consumed in the AO line. α-Amylase activity was distinctly suppressed in both the HP and the AO lines. Pre-germination β-amylase deposition was low in the AO grains and β-amylase was generally suppressed in both HP and AO lines throughout germination. As further supported by scanning electron microscopy and histochemical analyses on grain and seedlings, it was concluded that inadequate starch granule deposition in combination with the suppressed hydrolase activity leads to temporal and compensating re-direction of starch, sugar, and protein catabolism important to maintain metabolic dynamics during grain germination and seedling establishment. PMID:24642850

  10. Seed and Germination Characteristics of 20 Amazonian Liana Species

    PubMed Central

    Roeder, Mareike; Ferraz, Isolde D. K.; Hölscher, Dirk

    2013-01-01

    Lianas are an important component of tropical forests, and may reach their highest densities in disturbed areas. However, information on seed and germination characteristics is scarce. Twenty Amazon liana species were screened for their germination characteristics, including light dependence, tolerance of desiccation and of alternating temperatures; these characteristics are considered important for the germination success in areas with relatively open canopies. Between 31–1,420 seeds per species were available, as 15 species seeds came from one mother plant. We studied seed biometry and conducted germination trials with fresh seeds (12 h light daily, or dark) and desiccated seeds at 25 °C. Germination at alternating temperatures (20/30 °C, 15/35 °C) was analyzed for nine species. Of the 20 species, eight species with the largest seeds had desiccation sensitive seeds; this is the first record for species of four genera and one family, where only desiccation tolerant seeds are otherwise recorded. Light-dependent germination was found in three species (0.01–0.015 g) and is the first record for two; however, results were based on seeds from one plant per species. Alternating temperatures of 15/35 °C decreased final germination of four out of nine species, and response to 20/30 °C cycles varied compared to constant 25 °C. Seed and germination characteristics of the species ranged from pioneer to climax traits indicating that establishment of lianas from seeds may be confined to species specific niches. PMID:27137363

  11. Enhanced germination and gravitropism of soybean in a hypogeomagnetic field

    NASA Astrophysics Data System (ADS)

    Mo, Weichuan

    For the future manned space exploration, the duration of the missions would significantly in-crease. Investigating plant growth and development under the space environmental conditions is of essential importance for the food supply projects for the astronauts. Hypogeomagnetic field (HGMF), namely, extremely low magnetic field, is one of the main characters of the space environment. Germination is the first vital step of plant growth and development, which determines the final yield of plants. The effect of HGMF on plant growth, especially early ger-mination, still remains open. In this study, we established a hypogeomagnetic field (HGMF) incubation system, the remnant magnetic field inside no more than 250 nT. Soybean seeds were incubated at 25 in HGMF, and the very beginning of soybean germination, from water ab-sorbance of cotyledon to radicle emergence, was examined within 24 h. Our results showed that the germination ratio and weight ratio of emerged soybean radicles were markedly increased during germination in HGMF. Furthermore, the tropism angle of emerged radicle with gravity in HGMF was statistically smaller than that in GMF when the radicle direction was placed opposite to gravity before germination. These results indicate that the germination and gravit-ropism of soybean is enhanced in a hypogeomagnetic environment, This is a new finding about the early seed germination in such a low environmental magnetic field which is comparable to the magnetic field of Lunar Swirls on the Moon (a few hundred nT), and it might provide new perspectives on the space science researches concerning plant growth and food supply.

  12. Assessment of application-rate dependent effects of a long-term fire retardant chemical (Fire Trol 934) on Typha domingensis germination.

    PubMed

    Angeler, David G; Rodríguez, Marta; Martín, Silvia; Moreno, José M

    2004-05-01

    Although long-term fire retardants (LTR) gain increasingly acceptance as effective tools for wildfire management, recent studies indicate their potential harmfulness in the environment, especially in aquatic ecosystems. This study comprises a first laboratory impact assessment of LTR action in temporal Mediterranean wetlands, using seed germination of Typha domingensis as indicator of impact. Our aim was to identify application rates upon which seed germination could be significantly affected. We tested for low (1 l m(-2)) and high (3 l m(-2)) application rates of Fire Trol 934 which are recommended by the manufacturers as a function of fuel characteristics. In addition, we simulated the impact of a higher application rate of 5 l m(-2) because inhomogeneous dispersal of the LTR during fire control and prevention operations can result in locally elevated applications. Results of a microcosm experiment indicate that application rates of 1 or 3 l m(-2) can impact Typha germination rates in the short-term via indirect LTR-mediated effects on water quality, which suppressed necessary cues for germination. However, a subsequent experiment with Petri dishes, using seeds isolated from the LTR treated sediments did not show significantly different germination rates between the control and the treatments with application rates of 1 or 3 l m(-2). This suggests that retardant pre-application germination success could be recovered in nature once the retardant is eliminated. By contrast, seeds almost completely failed to germinate in the microcosm experiment and the subsequent Petri dish essay when an application rate of 5 l m(-2) was used. This suggests a critical level upon which Typha seed germination may be perpetually limited. Research should be extended to other plant species to provide fire managers with guidelines for environmentally safe use of LTR in the Mediterranean region. PMID:14987869

  13. Germination of Fusarium graminearum Ascospores and Wheat Infection are Affected by Dry Periods and by Temperature and Humidity During Dry Periods.

    PubMed

    Manstretta, V; Morcia, C; Terzi, V; Rossi, V

    2016-03-01

    The effects of temperature and relative humidity (RH) on germination of Fusarium graminearum ascospores, and of dry periods (DP) of different lengths and of temperature and RH during DP on ascospore survival were studied both in vitro and in planta. Optimal temperatures for ascospore germination at 100% RH were 20 and 25°C; germination was ≤5% when ascospores were incubated at 20°C and RH ≤ 93.5%. Viable ascospores were found at all tested combinations of DP duration (0 to 48 h) × temperature (5 to 40°C) or RH (32.5 to 100% RH). Germination declined as DP duration and temperature increased. Germination was lower for ascospores kept at 65.5% RH during the DP than at 76.0, 32.5, or 93.5% RH. Equations were developed describing the relationships between ascospore germination, DP duration and temperature or RH during DP. Durum wheat spikes were inoculated with ascospores and kept dry for 0 to 48 h at approximately 15°C and 65% RH; plants were then kept in saturated atmosphere for 48 h to favor infection. Fungal biomass, measured as F. graminearum DNA by quantitative polymerase chain reaction, declined as DP increased to 24 and 48 h at 3 and 9 days postinfection but not in spikes at maturity. PMID:26623994

  14. YY1 Is Required for Germinal Center B Cell Development

    PubMed Central

    Vuyyuru, Raja; Jha, Vibha; Hodewadekar, Suchita; Manser, Tim; Atchison, Michael L.

    2016-01-01

    YY1 has been implicated as a master regulator of germinal center B cell development as YY1 binding sites are frequently present in promoters of germinal center-expressed genes. YY1 is known to be important for other stages of B cell development including the pro-B and pre-B cells stages. To determine if YY1 plays a critical role in germinal center development, we evaluated YY1 expression during B cell development, and used a YY1 conditional knock-out approach for deletion of YY1 in germinal center B cells (CRE driven by the immunoglobulin heavy chain γ1 switch region promoter; γ1-CRE). We found that YY1 is most highly expressed in germinal center B cells and is increased 3 fold in splenic B cells activated by treatment with anti-IgM and anti-CD40. In addition, deletion of the yy1 gene by action of γ1-CRE recombinase resulted in significant loss of GC cells in both un-immunized and immunized contexts with corresponding loss of serum IgG1. Our results show a crucial role for YY1 in the germinal center reaction. PMID:27167731

  15. Conidial germination in the filamentous fungus Fusarium graminearum.

    PubMed

    Seong, Kye-Yong; Zhao, Xinhua; Xu, Jin-Rong; Güldener, Ulrich; Kistler, H Corby

    2008-04-01

    The ascomycetous fungus Fusarium graminearum is an important plant pathogen causing Fusarium head blight disease of wheat and barley. To understand early developmental stages of this organism, we followed the germination of macroconidia microscopically to understand the timing of key events. These events, recorded after suspension of spores in liquid germination medium, included spore swelling at 2h, germination tube emergence and elongation from conidia at 8h and hyphal branching at 24h. To understand changes in gene expression during these developmental changes, RNA was isolated from spores and used to interrogate the F. graminearum Affymetrix GeneChip. RNAs corresponding to 5813 genes were detected in fresh spores and 5146, 5249 and 5993, respectively, in spores incubated in germination medium after 2, 8 or 24h (P<0.001). Gene expression data were used to predict the cellular and physiological state of each developmental stage for known processes. Predictions were confirmed microscopically for several previously unreported developmental events such as manifestation of peroxisomes in fresh spores and nuclear division resulting in binuclear cells within macroconidia prior to spore germination. Knowledge of stage-specific gene expression and changes in gene expression levels between developmental stages are an important first step to understanding the molecular mechanisms responsible for spore germination and development. PMID:17950638

  16. Effects of diesel and kerosene on germination and growth of coastal wetland plant species.

    PubMed

    Kim, Kee Dae

    2014-11-01

    This study aims to investigate effects of diesel and kerosene on seed germination and seedling growth among coastal wetland plants to select species that can be used for the restoration and revegetation of oil-polluted habitats. Tests on 51 species were performed in Petri dishes containing 0 %, 6 %, 12 %, and 18 % diesel, 20 %, 40 %, and 60 % kerosene; each treatment combination was replicated five times with 20 seeds in each Petri dish. All dishes were held in a growth chamber with 20°C day of 12 h/15°C night of 12 h in 80 % humidity for 20 days for calculating the germination percentage, seedling weight, and seedling vitality. The germination percentage of Rumex stenophyllus decreased significantly in diesel and kerosene treatments. The weights of seedlings treated with diesel and kerosene either increased or decreased in comparison with controls depending on the species. Vitality percentage values were high for seedlings of Chenopodium ficifolium. Thus, herbaceous plant responses to oil treatments are species-specific. PMID:25138038

  17. Methyl anthranilate and γ-decalactone inhibit strawberry pathogen growth and achene Germination.

    PubMed

    Chambers, Alan H; Evans, Shane Alan; Folta, Kevin M

    2013-12-26

    Plant volatile compounds have been shown to affect microbial growth and seed germination. Here two fruity volatiles found in strawberry ( Fragaria × ananassa ), γ-decalactone ("peachlike" aroma) and methyl anthranilate ("grapelike" aroma), were tested for effects on relevant pathogens and seedling emergence. Significant growth reduction was observed for Botrytis cinerea , Colletotrichum gloeosporioides , Colletotrichum acutatum , Phomopsis obscurans , and Gnomonia fragariae at 1 mM γ-decalactone or methyl anthranilate, and 5 mM γ-decalactone or methyl anthranilate supplemented medium resulted in complete cessation of fungal growth. Phytophthora cactorum was especially sensitive to 1 mM γ-decalactone, showing complete growth inhibition. Bacteriostatic effects were observed in Xanthamonas cultures. Postharvest infestations on store-bought strawberries were inhibited with volatile treatment. The γ-decalactone volatile inhibited strawberry and Arabidopsis thaliana germination. These findings show that two compounds contributing to strawberry flavor may also contribute to shelf life and suggest that γ-decalactone may play an ecological role by preventing premature germination. PMID:24328200

  18. A Novel Preclinical Model of Germinal Matrix Hemorrhage Using Neonatal Rats

    PubMed Central

    Lekic, Tim; Manaenko, Anatol; Rolland, William; Tang, Jiping

    2013-01-01

    Background Germinal matrix hemorrhage (GMH) is a neurological disorder associated with very low birth weight premature infants. This event can lead to post-hemorrhagic hydrocephalus, cerebral palsy, and mental retardation. This study developed a novel animal model for pre-clinical investigations. Methods Neonatal rats underwent infusion of clostridial collagenase into the right germinal matrix (anterior caudate) region using stereotaxic techniques. Developmental milestones were evaluated over 10 days, cognitive function at 3 weeks, and sensorimotor function at 4 weeks after collagenase infusion. This was accomplished by anthropometric quantifications of cranial, cerebral, cardiac, and splenic growths. Results Collagenase infusion led to delays in neonatal developmental milestones, followed by cognitive and sensorimotor dysfunctions in the juvenile animals. Cranial growth was accelerated during the first week after injury, and this was followed by significant brain atrophy, splenomegaly, and cardiac hypertrophy 3 weeks later. Conclusion This study characterized the developmental delays, mental retardation, and cerebral palsy features resembling the long-term clinical course after germinal matrix hemorrhage in premature infants. Pre-clinical testing of therapeutics in this experimental model could lead to improved patient outcomes while expanding upon the pathophysiological understanding of this disease. PMID:21725732

  19. Development of an Automated Seed Sowing and Induced Germination System for Space Flight Application

    NASA Technical Reports Server (NTRS)

    Heyenga, A. G.; Kliss, Mark

    1995-01-01

    The successful utilization of higher plants in space flight is likely to require the effective transition of plants through all phases of growth and development. A particularly sensitive and critical stage in this cycle is seed germination. The present inflight capability to manipulate seed from a state of dormancy to germination and the performance of such activity under aseptic conditions is extremely limited. An Automated Sowing Mechanism (ASM) has been designed to address this area of science and technology. The self-contained system is readily compatible with the existing Shuttle middeck locker Plant Growth Unit (PGU) and planned Plant Growth Facility (PGF), presenting an opportunity to extend the experimental capability of these systems. The ASM design encompasses the controlled transition of seed from a dry to hydrated state utilizing solid media substrate as the source of water and nutrient support. System activation has been achieved with both photo and timing mechanisms. Controlled induced germination and development of various plant species has been achieved in ground-based trials. The system is presently being prepared for a KC-135 flight test.

  20. Effects of Atmospheric Pressure Air Plasma Pretreatment on the Seed Germination and Early Growth of Andrographis paniculata

    NASA Astrophysics Data System (ADS)

    Tong, Jiayun; He, Rui; Zhang, Xiaoli; Zhan, Ruoting; Chen, Weiwen; Yang, Size

    2014-03-01

    The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata (A. paniculata) seedlings by modifying the seed coat and finding a beneficial treatment dose. Eight treatment doses and one control were used to conduct electrical conductivity determination, a germination test, a seedling emergence test and a biochemical assay. The results showed that after being treated with air plasma excited at 5950 V for 10 s, the permeability of the seeds was improved significantly, resulting in the acceleration of seed germination and seedling emergence. In the meantime, the catalase activity and catalase isoenzyme expression were also improved, while the malondialdehyde content in the seedlings was decreased (which means greater counteraction with environmental stress). After being treated with 4250 V for 10 s and 5950 V for 20 s, the seed germination was enhanced, but without an obvious change in seedling emergence. However, after treatment with 3400 V for 20 s and 5100 V for 10 s, the permeability of the seeds was decreased, resulting in a delay in seedling emergence. These results indicate that air plasma can change the physiological and biochemical characteristics of Andrographis paniculata seeds by modifying the seed coat, combined with the effects of the active plasma species, and that different treating doses have different effects.

  1. Defects in Germinal Center Selection in SLE

    PubMed Central

    Woods, Megan; Zou, Yong-Rui; Davidson, Anne

    2015-01-01

    Germinal centers (GCs) are the primary site at which clonal expansion and affinity maturation of B cells occur. B cells encounter antigen and receive T cell help in the GC light zone (LZ) and then migrate to the dark zone where they proliferate and undergo somatic mutation before cycling back to the LZ for further rounds of selection. Tolerance to autoantigens is frequently lost de novo as GC B cells undergo class switching and somatic mutation. This loss of tolerance is regulated by a variety of mechanisms including cell death, failure to compete for T cell help, and failure to differentiate into effector cells. Systemic lupus erythematosus (SLE) is characterized by loss of tolerance to nucleic acid antigens. While defects in tolerance occur in the naïve repertoire of SLE patients, pathogenic autoantibodies also arise in the GC by somatic mutation from non-autoreactive precursors. Several B cell defects contribute to the loss of GC tolerance in SLE, including polymorphisms of genes encoded by the Sle1 locus, excess TLR7 signaling, defects in FcRIIB expression, or defects of B cell apoptosis. Extrinsic soluble factors, such as Type-1 IFN and B cell-activating factor, or an increased number of T follicular helper cells in the GC also alter B cell-negative selection. Finally, defects in clearance of apoptotic debris within the GC result in BCR-mediated internalization of nucleic acid containing material and stimulation of autoantibody production by endosomal TLR-driven mechanisms. PMID:26322049

  2. Inhibition of urediniospore germination Puccinia hemerocallidis by Bacto Agar and changes in percent germination and germ-tube elongation on agarose over time.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of some gelling agents and pH on urediniospore germination and germ tube elongation of Puccinia hemerocallidis were investigated in vitro. Gelling agents significantly affected urediniospore germination. Very few urediniospores germinated on the substrates containing more than 0.5% Bacto...

  3. Genes related to high temperature tolerance during maize seed germination.

    PubMed

    Dutra, S M F; Von Pinho, E V R; Santos, H O; Lima, A C; Von Pinho, R G; Carvalho, M L M

    2015-01-01

    The identification of genes related to heat tolerance is fundamental for the development of high-quality seeds that are tolerant to heat stress condition. The objective of this study was to evaluate maize lineages and the gene expression involved in high temperature tolerance during germination using physiological tests, proteomics, and transcriptome analysis. Seeds from six maize lineages (30, 44, 54, 63, 64, and 91) with different levels of tolerance to high temperatures were used. Lineages 54 and 91 were observed to be more tolerant to high temperature conditions. The highest expression of α-amylase was observed in maize seeds from lineages 30 and 91 that were subjected to controlled deterioration. The highest expression of α-amylase was observed in maize seeds from lineages 30 and 91 that were subjected to controlled deterioration; with the controlled deterioration, the highest level of gene expression did not occur in the most tolerant materials; the association of lower expression of genes involved in heat-resistant protein systems was observed in seeds from lineage 44, which were more susceptible to high temperatures, and the highest gene expression of LEA D-34, ZmAN13, and AOX-1 was observed in seeds from lineage 64 when submitted to controlled deterioration. PMID:26782452

  4. Intranasal IGF-1 Reduced Rat Pup Germinal Matrix Hemorrhage.

    PubMed

    Lekic, Tim; Flores, Jerry; Klebe, Damon; Doycheva, Desislava; Rolland, William B; Tang, Jiping; Zhang, John H

    2016-01-01

    Germinal matrix hemorrhage (GMH) is the most devastating neurological problem of premature infants. Current treatment strategies are ineffective and brain injury is unpreventable. Insulin-like growth factor 1 (IGF-1) is an endogenous protein shown to have multiple neuroprotective properties. We therefore hypothesized that IGF-1 would reduce brain injury after GMH. Neonatal rats (P7 age) received stereotactic collagenase into the right ganglionic eminence. The following groups were studied: (1) sham, (2) GMH + vehicle, (3) GMH + intranasal IGF-1. Three days later, the animals were evaluated using the righting-reflex (early neurobehavior), Evans blue dye leakage (blood-brain barrier (BBB) permeability), brain water content (edema), and hemoglobin assay (extent of bleeding). Three weeks later, juvenile rats were tested using a water maze (delayed neurobehavior), and then were sacrificed on day 28 for assessment of hydrocephalus (ventricular size). Intranasal IGF-1 treated animals had improved neurological function, and amelioration of BBB permeability, edema, and re-bleeding. IGF-1 may play a part in protective brain signaling following GMH, and our observed protective effect may offer new promise for treatment targeting this vulnerable patient population. PMID:26463950

  5. Seed priming to alleviate salinity stress in germinating seeds.

    PubMed

    Ibrahim, Ehab A

    2016-03-15

    Salinity is one of the major abiotic stresses that affect crop production in arid and semiarid areas. Seed germination and seedling growth are the stages most sensitive to salinity. Salt stress causes adverse physiological and biochemical changes in germinating seeds. It can affect the seed germination and stand establishment through osmotic stress, ion-specific effects and oxidative stress. The salinity delays or prevents the seed germination through various factors, such as a reduction in water availability, changes in the mobilization of stored reserves and affecting the structural organization of proteins. Various techniques can improve emergence and stand establishment under salt conditions. One of the most frequently utilized is seed priming. The process of seed priming involves prior exposure to an abiotic stress, making a seed more resistant to future exposure. Seed priming stimulates the pre-germination metabolic processes and makes the seed ready for radicle protrusion. It increases the antioxidant system activity and the repair of membranes. These changes promote seed vigor during germination and emergence under salinity stress. The aim of this paper is to review the recent literature on the response of plants to seed priming under salinity stress. The mechanism of the effect of salinity on seed germination is discussed and the seed priming process is summarized. Physiological, biochemical and molecular changes induced by priming that lead to seed enhancement are covered. Plants' responses to some priming agents under salinity stress are reported based on the best available data. For a great number of crops, little information exists and further research is needed. PMID:26812088

  6. Different Modes of Hydrogen Peroxide Action During Seed Germination

    PubMed Central

    Wojtyla, Łukasz; Lechowska, Katarzyna; Kubala, Szymon; Garnczarska, Małgorzata

    2016-01-01

    Hydrogen peroxide was initially recognized as a toxic molecule that causes damage at different levels of cell organization and thus losses in cell viability. From the 1990s, the role of hydrogen peroxide as a signaling molecule in plants has also been discussed. The beneficial role of H2O2 as a central hub integrating signaling network in response to biotic and abiotic stress and during developmental processes is now well established. Seed germination is the most pivotal phase of the plant life cycle, affecting plant growth and productivity. The function of hydrogen peroxide in seed germination and seed aging has been illustrated in numerous studies; however, the exact role of this molecule remains unknown. This review evaluates evidence that shows that H2O2 functions as a signaling molecule in seed physiology in accordance with the known biology and biochemistry of H2O2. The importance of crosstalk between hydrogen peroxide and a number of signaling molecules, including plant phytohormones such as abscisic acid, gibberellins, and ethylene, and reactive molecules such as nitric oxide and hydrogen sulfide acting on cell communication and signaling during seed germination, is highlighted. The current study also focuses on the detrimental effects of H2O2 on seed biology, i.e., seed aging that leads to a loss of germination efficiency. The dual nature of hydrogen peroxide as a toxic molecule on one hand and as a signal molecule on the other is made possible through the precise spatial and temporal control of its production and degradation. Levels of hydrogen peroxide in germinating seeds and young seedlings can be modulated via pre-sowing seed priming/conditioning. This rather simple method is shown to be a valuable tool for improving seed quality and for enhancing seed stress tolerance during post-priming germination. In this review, we outline how seed priming/conditioning affects the integrative role of hydrogen peroxide in seed germination and aging. PMID:26870076

  7. Germination Season and Watering Regime, but Not Seed Morph, Affect Life History Traits in a Cold Desert Diaspore-Heteromorphic Annual

    PubMed Central

    Lu, Juan J.; Tan, Dun Y.; Baskin, Jerry M.; Baskin, Carol C.

    2014-01-01

    Seed morph, abiotic conditions and time of germination can affect plant fitness, but few studies have tested their combined effects on plasticity of plant life history traits. Thus, we tested the hypothesis that seed morph, germination season and watering regime influence phenotypic expression of post-germination life history traits in the diaspore-heteromorphic cold desert winter annual/spring ephemeral Diptychocarpus strictus. The two seed morphs were sown in watered and non-watered plots in late summer, and plants derived from them were watered or not-watered throughout the study. Seed morph did not affect phenology, growth and morphology, survival, dry mass accumulation and allocation or silique and seed production. Seeds in watered plots germinated in autumn (AW) and spring (SW) but only in spring for non-watered plots (SNW). A high percentage of AW, SW and SNW plants survived and reproduced, but flowering date and flowering period of autumn- vs. spring-germinated plants differed. Dry mass also differed with germination season/watering regime (AW > SW > SNW). Number of siliques and seeds increased with plant size (AW > SW > SNW), whereas percent dry mass allocated to reproduction was higher in small plants: SNW > SW > AW. Thus, although seed morph did not affect the expression of life history traits, germination season and watering regime significantly affected phenology, plant size and accumulation and allocation of biomass to reproduction. Flexibility throughout the life cycle of D. strictus is an adaptation to the variation in timing and amount of rainfall in its cold desert habitat. PMID:25013967

  8. 7 CFR 201.30a - Date of test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30a Date of test. When the percentage of germination is required to be shown, the label shall show the month and year in which the germination test was completed....

  9. 7 CFR 201.30a - Date of test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30a Date of test. When the percentage of germination is required to be shown, the label shall show the month and year in which the germination test was completed....

  10. 7 CFR 201.30a - Date of test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30a Date of test. When the percentage of germination is required to be shown, the label shall show the month and year in which the germination test was completed....

  11. 7 CFR 201.22 - Date of test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT... which the germination test was completed. No more than 5 calendar months shall have elapsed between the last day of the month in which the germination test was completed and the date of transportation...

  12. 7 CFR 201.30a - Date of test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30a Date of test. When the percentage of germination is required to be shown, the label shall show the month and year in which the germination test was completed....

  13. 7 CFR 201.22 - Date of test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT... which the germination test was completed. No more than 5 calendar months shall have elapsed between the last day of the month in which the germination test was completed and the date of transportation...

  14. 7 CFR 201.30a - Date of test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30a Date of test. When the percentage of germination is required to be shown, the label shall show the month and year in which the germination test was completed....

  15. 7 CFR 201.22 - Date of test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT... which the germination test was completed. No more than 5 calendar months shall have elapsed between the last day of the month in which the germination test was completed and the date of transportation...

  16. 7 CFR 201.22 - Date of test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT... which the germination test was completed. No more than 5 calendar months shall have elapsed between the last day of the month in which the germination test was completed and the date of transportation...

  17. 7 CFR 201.22 - Date of test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT... which the germination test was completed. No more than 5 calendar months shall have elapsed between the last day of the month in which the germination test was completed and the date of transportation...

  18. The evolution of the paleomagnetic fold test as applied to complex geologic situations, illustrated by a case study from northern Spain

    NASA Astrophysics Data System (ADS)

    Weil, Arlo B.; Van der Voo, Rob

    Paleomagnetic results are most useful if the age of the magnetization can be established with respect to the rock age or the age of specific structural or alteration events. The fold test is a particularly powerful tool; not only can it be used to determine whether magnetizations are pre-, syn- or post-folding, but it can also reassure us that structural corrections need (or need not) be applied to a given magnetization. This study traces the evolution of various fold and tilt tests developed in the 50-some years since the classical test of Graham was published. Syn-deformational magnetizations are a very special case, usually characterized as such by an incremental tilt test. In regions where rotations about (near-) vertical axes are to be expected, a strike test is the best tool for determining them. A case study of syn-deformational magnetizations in the Cantabria-Asturias Arc (CAA) of northern Spain is presented, which illustrates the application of the various tilt and strike tests. One ancient post-deformational and two syn-deformational magnetizations have been recorded in CAA Devonian carbonates, each characterized by different optimal (peak) percentages of unfolding in incremental fold tests. The structural corrections required to bring the individual site-mean magnetization directions into alignment can be used to restore the beds to their attitudes at the times when the magnetizations were acquired. Furthermore, these structural corrections provide robust constraints on the kinematics of the deformation phase that is being removed. In the CAA, removal of late-stage folding about steeply inclined fold axes, due to Permian oroclinal bending, restores the belt to its first folding and thrusting configuration, and produces north-south trending cylindrical folds that formed during the Late Carboniferous. The separate deformations, consisting of earlier folding and thrusting and later oroclinal bending, have implications for the final collisional movements

  19. Distribution of three congeneric shrub species along an aridity gradient is related to seed germination and seedling emergence.

    PubMed

    Lai, Liming; Tian, Yuan; Wang, Yongji; Zhao, Xuechun; Jiang, Lianhe; Baskin, Jerry M; Baskin, Carol C; Zheng, Yuanrun

    2015-01-01

    Environmental tolerance of a species has been shown to correlate positively with its geographical range. On the Ordos Plateau, three Caragana species are distributed sequentially along the precipitation gradient. We hypothesized that this geographical distribution pattern is related to environmental tolerances of the three Caragana species during seed germination and seedling emergence stages. To test this hypothesis, we examined seed germination under different temperature, light and water potentials, and monitored seedling emergence for seeds buried at eight sand depths and given different amounts of water. Seeds of C. korshinskii germinated to high percentages at 5 : 15 to 25 : 35 °C in both light and darkness, while those of C. intermedia and C. microphylla did so only at 15 : 25 and 25 : 35 °C, respectively. Nearly 30 % of the C. korshinskii seeds germinated at -1.4 MPa at 20 and 25 °C, while no seeds of the other two species did so. Under the same treatments, seedling emergence percentages of C. korshinskii were higher than those of the other two species. The rank order of tolerance to drought and sand burial of the three species is C. korshinskii > C. intermedia > C. microphylla. The amount of precipitation and sand burial depth appear to be the main selective forces responsible for the geographical distribution of these species. PMID:26139184

  20. Distribution of three congeneric shrub species along an aridity gradient is related to seed germination and seedling emergence

    PubMed Central

    Lai, Liming; Tian, Yuan; Wang, Yongji; Zhao, Xuechun; Jiang, Lianhe; Baskin, Jerry M.; Baskin, Carol C.; Zheng, Yuanrun

    2015-01-01

    Environmental tolerance of a species has been shown to correlate positively with its geographical range. On the Ordos Plateau, three Caragana species are distributed sequentially along the precipitation gradient. We hypothesized that this geographical distribution pattern is related to environmental tolerances of the three Caragana species during seed germination and seedling emergence stages. To test this hypothesis, we examined seed germination under different temperature, light and water potentials, and monitored seedling emergence for seeds buried at eight sand depths and given different amounts of water. Seeds of C. korshinskii germinated to high percentages at 5 : 15 to 25 : 35 °C in both light and darkness, while those of C. intermedia and C. microphylla did so only at 15 : 25 and 25 : 35 °C, respectively. Nearly 30 % of the C. korshinskii seeds germinated at −1.4 MPa at 20 and 25 °C, while no seeds of the other two species did so. Under the same treatments, seedling emergence percentages of C. korshinskii were higher than those of the other two species. The rank order of tolerance to drought and sand burial of the three species is C. korshinskii > C. intermedia > C. microphylla. The amount of precipitation and sand burial depth appear to be the main selective forces responsible for the geographical distribution of these species. PMID:26139184