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1

9 CFR 327.19 - Specimens for laboratory examination and similar purposes.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Specimens for laboratory examination and similar purposes...327.19 Specimens for laboratory examination and similar purposes...specimens of products for laboratory examination, research, or similar purposes...

2010-01-01

2

Similarity  

NSDL National Science Digital Library

In this workshop session, elementary and middle school teachers explore scale drawing, similar triangles, and trigonometry in terms of ratios and proportion. Besides explanations and real-world problems, the unit includes video segments that show teachers investigating problems of similarity. To understand the ratios that underlie trigonometry, participants use an interactive activity provided online. This is session 8 of Learning Math: Geometry, a free online course.

Manes, Michelle

2003-01-01

3

Finding Images with Similar Lighting Conditions in Large Photo Collections  

E-print Network

image databases such as Flickr or Picasaweb. Computer vision scientists have not taken too much time from outdoor scenes, much of the information perceived is due to the ligthing conditions with a compact camera to share their visual experiences. This fact has been the starting point for large online

Paris-Sud XI, Université de

4

Evaluation of Laboratory Conditioning Protocols for Warm-Mix Asphalt  

E-print Network

laboratory conditioning procedure for preparing WMA specimens for performance tests, despite being essential for mix performance. Based on previous studies, several candidate conditioning protocols for WMA Laboratory Mixed Laboratory Compacted (LMLC...

Yin, Fan 1990-

2012-10-26

5

Conditional mixing statistics in a self-similar scalar mixing layer  

NASA Astrophysics Data System (ADS)

Conditional scalar mixing statistics from a three-dimensional direct numerical simulation (DNS) of a scalar mixing layer are presented in the context of modeling nonpremixed turbulent combustion. The simulation is closely matched to a particular laboratory experiment but with slight adjustments so that the simulated flow is very nearly self-similar. All statistics commonly used in mixing models are presented, along with comparisons to models and laboratory data where available. A model for the conditional scalar dissipation rate (CSD), recently introduced by Mortensen ["Consistent modeling of scalar mixing for presumed multiple parameter probability density functions," Phys. Fluids 17, 018106 (2005)], is tested against the data set, as is a Lagrangian stochastic trajectory technique recently published by Sawford ["Conditional scalar mixing statistics in homogenous isotropic turbulence," New J. Phys. 6, 1 (2004)]. It is concluded that (i) the DNS data set provides an excellent, high-resolution description of the scalar mixing layer that can be used for developing and verifying models for scalar mixing; (ii) the self-consistent CSD model of Mortensen is necessary for consistent implementations of the conditional moment closure, but for the current flow it gives only small adjustments to the more commonly adopted model of Girimaji ["On the modeling of scalar diffusion in isotropic turbulence," Phys. Fluids A 4, 2529 (1992)]; and (iii) Sawford's Lagrangian technique very closely predicts the DNS results.

de Bruyn Kops, Stephen M.; Mortensen, Mikael

2005-09-01

6

Scaling of Turbidity Currents and Riverine Flows for Laboratory Experiments: similarities and differences  

NASA Astrophysics Data System (ADS)

Riverine flows are commonly studies in the laboratory with the help of Froude scale models. While Froude scaling ensures similarity between model and prototype regarding flow velocity magnitude and distribution, the presence of a movable erodible bed makes it necessary to use another criterion to ensure similarity of sediment transport. This results in the need to use material that has a smaller specific gravity than the sediment in the protototype (e.g. crushed walnut shells, coal). Often times the model has to be "tilted" in order to have measurable flow depths and sediment transport. However, scale effects can still manifest themselves through the development of bedforms in the model that do not correspond to those observed in nature for the equivalent flow conditions. On the other hand, turbidity currents, capable of transporting sediment for very long distances in lakes, reservoirs and the ocean, have to be modeled with help of a densimetric Froude number or equivalently the Richardson number. Unlike the case of riverine flows, light weight materials can not be used to model turbidity currents since this would result in volumetric concentrations that are too large and make the suspension non-dilute. Examples of small scale models of the Tanana River in Alaska and lake sedimentation by turbidity currents generated by the disposal of mining tailing in Labrador, Canada, will be presented. Interpretation of physical modeling results and potential scale effects will be discussed together with some of the challenges associated with physical modeling of sediment transport phenomena.

Garcia, M. H.

2011-12-01

7

Conditional Mixing Statistics in a Self-Similar Scalar Mixing Layer  

NASA Astrophysics Data System (ADS)

Conditional scalar mixing statistics from a three-dimensional direct numerical simulation (DNS) of a scalar mixing layer are presented in the context of modeling non-premixed turbulent combustion. The simulation is closely matched to a particular laboratory experiment but with slight adjustments so that the simulated flow is very nearly self-similar. All statistics commonly used in mixing models are presented, along with comparisons to models and laboratory data where available. A model for the conditional scalar dissipation rate (CSD), recently introduced by Mortensen, is tested against the data set, as is a Lagrangian stochastic trajectory technique recently published by Sawford. It is concluded that (i) the DNS data set provides an excellent, high resolution description of the scalar mixing layer that can be used for developing and verifying models for scalar mixing; (ii) the self-consistent CSD model of Mortensen is necessary for consistent implementations of the conditional moment closure, but, for the current flow it gives only small adjustments to the more commonly adopted model of Girimaji; and (iii) Sawford's Lagrangian technique very closely predicts the DNS results.

de Bruyn Kops, Stephen; Mortensen, Mikael

2005-11-01

8

Similarity Parameter Evolution within a Magnetic Nozzle with Applications to Laboratory Plasmas  

E-print Network

Similarity Parameter Evolution within a Magnetic Nozzle with Applications to Laboratory Plasmas of the expanding plasma is then used to determine the evolution of these parameters downstream from the nozzle anisotropies (Ti, = Ti,) and species non-equilibrium (Te = Ti) effects may alter the means by which ions

Choueiri, Edgar

9

Triangle Similarity. Geometry Module for Use in a Mathematics Laboratory Setting.  

ERIC Educational Resources Information Center

This is one of a series of geometry modules developed for use by secondary students in a laboratory setting. The purpose of this module is to teach solution of proportions, concepts and theorems of triangle similarity, solution of the Pythagorean Theorem, solution of the isosceles right triangle, and concepts involving "rep-tile" figures as well…

Brotherton, Sheila; And Others

10

Similarity Properties and Scaling Laws of Radiation Hydrodynamic Flows in Laboratory Astrophysics  

E-print Network

The spectacular recent development of modern high-energy density laboratory facilities which concentrate more and more energy in millimetric volumes allows the astrophysical community to reproduce and to explore, in millimeter-scale targets and during very short times, astrophysical phenomena where radiation and matter are strongly coupled. The astrophysical relevance of these experiments can be checked from the similarity properties and especially scaling laws establishment, which constitutes the keystone of laboratory astrophysics. From the radiating optically thin regime to the so-called optically thick radiative pressure regime, we present in this paper, for the first time, a complete analysis of the main radiating regimes that we encountered in laboratory astrophysics with the same formalism based on the Lie-group theory. The use of the Lie group method appears as systematic which allows to construct easily and orderly the scaling laws of a given problem. This powerful tool permits to unify the recent major advances on scaling laws and to identify new similarity concepts that we discuss in this paper and which opens important applications for the present and the future laboratory astrophysics experiments. All these results enable to demonstrate theoretically that astrophysical phenomena in such radiating regimes can be explored experimentally thanks to powerful facilities. Consequently the results presented here are a fundamental tool for the high-energy density laboratory astrophysics community in order to quantify the astrophysics relevance and justify laser experiments. Moreover, relying on the Lie-group theory, this paper constitutes the starting point of any analysis of the self-similar dynamics of radiating fluids.

Emeric Falize; Claire Michaut; Serge Bouquet

2009-10-13

11

Environmental bias? Effects of housing conditions, laboratory environment and experimenter on behavioral tests.  

PubMed

Behavioral testing does not always yield similar results when replicated in different laboratories, and it usually remains unclear whether the variability in results is caused by different laboratory environments or different experimenters conducting the tests. In our study, we applied a systematic variation of housing conditions, laboratories and experimenters in order to test the influence of these variables on the outcome of behavioral tests. We wanted to know whether known effects of different housing conditions on behavior can be demonstrated regardless of the respective laboratory and experimenters. In this study, we compared the behavior of mice kept under enriched housing conditions with mice kept in unstructured cages regarding their exploratory, locomotor and anxiety-related behavior in the barrier test, in the open-field test and in the elevated plus-maze test. Experiments were conducted by six different persons in two different laboratories. In spite of an extensive protocol standardizing laboratory environment, animal maintenance and testing procedures, significant differences in absolute values between different laboratories as well as between different experimenters were noticed in the barrier test and in the elevated plus-maze test but not in the open-field test. However, with regard to the differences between enriched and unstructured housing conditions, overall consistent results were achieved by different experimenters in both laboratories. We conclude that the reliability of behavioral phenotyping is not challenged seriously by experimenter and laboratory environment as long as appropriate standardizations are met and suitable controls are involved. PMID:16436190

Lewejohann, L; Reinhard, C; Schrewe, A; Brandewiede, J; Haemisch, A; Görtz, N; Schachner, M; Sachser, N

2006-02-01

12

Gender similarities and differences in sexual arousal, desire, and orgasmic pleasure in the laboratory.  

PubMed

Relatively little is known about gender differences in the orgasm experience. The objectives of this study were to compare men's and women's patterns of sexual arousal and desire before and after orgasm, and the predictors of their orgasmic pleasure. Using their typical technique, where masturbation enjoyment was similar to that experienced at home, 38 men and 38 women masturbated to orgasm in the laboratory. Physiological sexual arousal (genital temperature) and subjective sexual arousal and desire measurements were taken at baseline, after masturbation almost to orgasm, and immediately and 15 minutes after orgasm. In both genders, all measures increased significantly during masturbation, with a greater buildup leading to a more pleasurable orgasm. After orgasm, however, sexual arousal and desire decreased more quickly and consistently in men than in women, thereby replicating Masters and Johnson's (1966) observations. More men than women exhibited resolution of subjective sexual arousal and sexual satiation; their genital temperature also decreased more than women's but did not return to baseline. Women's orgasmic pleasure was related to a postorgasmic decrease in genital temperature but, unexpectedly, the maintenance of subjective sexual arousal and desire. Future studies should explore whether this pattern explains gender differences in the pursuit of additional orgasms. PMID:24588445

Paterson, Laurel Q P; Jin, Ellie Shuo; Amsel, Rhonda; Binik, Yitzchak M

2014-01-01

13

Observational evidence for the Monin-Obukhov similarity under all stability conditions  

NASA Astrophysics Data System (ADS)

Data collected in the surface layer in a northern suburban area of Nanjing from 15 November to 29 December 2007 were analyzed to examine the Monin-Obukhov similarity for describing the turbulent fluctuations of 3D winds under all stability conditions and to obtain the turbulence characteristics under different weather conditions. The results show that the dimensionless standard deviations of turbulent velocity components ( ? u / u*, ? ? / u*, ? w / u*) and dimensionless turbulent kinetic energy (TKE) can be well described by "1/3" power law relationships under stable, neutral, and unstable conditions, with ? u / u* > ? ? / u* > ? w / u*. Land use and land cover changes mainly impact dimensionless standard deviations of horizontal component fluctuations, but they have very little on those of the vertical component. The dimensionless standard deviations of wind components and dimensionless TKE are remarkably affected by different weather conditions; the deviations of horizontal wind component and dimensionless TKE present fog day > clear sky > overcast > cloudy; the trend of the vertical wind component is the reverse. The surface drag coefficient at a Nanjing suburban measurement site during the observation period was obviously higher than at other reported plains and plateau areas, and was approximately one order larger in magnitude than the reported plains areas. Dimensionless standard deviation of temperature declined with increasing |z'/ L| with an approximate "-1/3" slope in unstable stratification and "-2/3" slope in stable stratification.

Niu, Shengjie; Zhao, Lijuan; Lu, Chunsong; Yang, Jun; Wang, Jing; Wang, Weiwei

2012-03-01

14

Seal formation in arid soil under natural and laboratory conditions  

NASA Astrophysics Data System (ADS)

Runoff is of considerable importance in the functioning of a desert ecosystem. The hydrological characteristics of runoff developing on arid soil under natural field conditions and those of runoff occurring in laboratory-controlled rain simulation experiments using the same type of soil were investigated. Runoff and erosion measurements were carried out in small plots (0.2-0.8 m2) on a south-facing hillslope in the northern Negev, Israel (90 mm ave. annual rainfall). Soil from the area near to the runoff plots was collected for the rain simulation experiments conducted in the laboratory. The soil was collected from 0-1 cm and 1-5 cm depths, and then placed within boxes (1.16 m long and 0.55 m wide) in the laboratory in the same order as they had been in the field. Representative surface stones were collected in the field and scattered randomly on the soil surface in the laboratory boxes. In some of the laboratory experiments soil, 5 cm in depth, was placed on a geotechnical sheet on a metal screen, while in other experiments, soil of 5 cm depth was placed on a Terzaghi filter. Rain simulator used had a rotating disk with a tilted nozzle to simulate raindrop size dispersion and kinetic energy of natural rain. The sprinkling intensity was set at a rate of 18 mm/hour. Soil crusts in the field were more stable than those created in the lab for two standard tests: Emerson - immersion test, and the 'single water drop' test. Whereas weak activity of microphytes was found in the field there was no such activity in the lab. The rain depth until runoff in the field was less than under laboratory conditions, while the sediment yield was greater in the field than in the laboratory (8.64 g/m2 versus 0.58 g/m2). The rain simulator experiments that had included a Terzaghi filter showed significantly higher final infiltration rate (7.5 mm/h versus 4.2 mm/h), shorter accumulated watering depth until stabilization of soil seal formation (100-200 mm versus 50 mm), and smaller fraction of clay in the crust (4.2% versus 6.8%), than the experiments that done without this filter. Therefore, it is conceivable that there is a suction of thin material from the surface while capillary pressures are activated, result in sub-surface seal formation (washed-in layer). This can lead to differences between runoff-forming processes existing in the laboratory set-up and processes that occur under natural field conditions.

Sarah, Pariente; Sachs, Eyal

2013-04-01

15

Availability and Persistence of Isoproturon under Field and Laboratory Conditions  

Microsoft Academic Search

Field and laboratory tests were conducted to investigate the disappearance and decrease in availability of the herbicide isoproturon in soil with time. Monitoring the fate of14C-labeled isoproturon gave the persistence of the herbicide under different conditions. The calculated half-life (DT50) of the extractable parent product was close to 19 days for the two experiments, whereas half-lives of exhaustive extractable14C-residues averaged

C. Perrin-Ganier; C. Breuzin; J. M. Portal; M. Schiavon

1996-01-01

16

Biogenic oxidized organic functional groups in aerosol particles from a mountain forest site and their similarities to laboratory chamber products  

NASA Astrophysics Data System (ADS)

Submicron particles collected at Whistler, British Columbia, at 1020 m a.s.l. during May and June 2008 on Teflon filters were analyzed by Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) techniques for organic functional groups (OFG) and elemental composition. Organic mass (OM) concentrations ranged from less than 0.5 to 3.1 ?g m-3, with a project mean and standard deviation of 1.3±1.0 ?g m-3 and 0.21±0.16 ?g m-3 for OM and sulfate, respectively. On average, organic hydroxyl, alkane, and carboxylic acid groups represented 34%, 33%, and 23% of OM, respectively. Ketone, amine and organosulfate groups constituted 6%, 5%, and <1% of the average organic aerosol composition, respectively. Measurements of volatile organic compounds (VOC), including isoprene and monoterpenes from biogenic VOC (BVOC) emissions and their oxidation products (methyl-vinylketone / methacrolein, MVK/MACR), were made using co-located proton transfer reaction mass spectrometry (PTR-MS). We present chemically-specific evidence of OFG associated with BVOC emissions. Positive matrix factorization (PMF) analysis attributed 65% of the campaign OM to biogenic sources, based on the correlations of one factor to monoterpenes and MVK/MACR. The remaining fraction was attributed to anthropogenic sources based on a correlation to sulfate. The functional group composition of the biogenic factor (consisting of 32% alkane, 25% carboxylic acid, 21% organic hydroxyl, 16% ketone, and 6% amine groups) was similar to that of secondary organic aerosol (SOA) reported from the oxidation of BVOCs in laboratory chamber studies, providing evidence that the magnitude and chemical composition of biogenic SOA simulated in the laboratory is similar to that found in actual atmospheric conditions. The biogenic factor OM is also correlated to dust elements, indicating that dust may act as a non-acidic SOA sink. This role is supported by the organic functional group composition and morphology of single particles, which were analyzed by scanning transmission X-ray microscopy near edge X-ray absorption fine structure (STXM-NEXAFS).

Schwartz, R. E.; Russell, L. M.; Sjostedt, S. J.; Vlasenko, A.; Slowik, J. G.; Abbatt, J. P. D.; MacDonald, A. M.; Li, S. M.; Liggio, J.; Toom-Sauntry, D.; Leaitch, W. R.

2010-06-01

17

Biogenic oxidized organic functional groups in aerosol particles from a mountain forest site and their similarities to laboratory chamber products  

NASA Astrophysics Data System (ADS)

Submicron particles collected at Whistler, British Columbia, at 1020 masl during May and June 2008 on Teflon filters were analyzed by Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) techniques for organic functional groups (OFG) and elemental composition. Organic mass (OM) ranged from less than 0.5 to 3.1?g m-3, with a project mean and standard deviation of 1.3±1.0 ?g m-3 and 0.21±0.16 ?g m-3 for OM and sulfate, respectively. On average, organic hydroxyl, alkane, and carboxylic acid groups represented 34%, 33%, and 23% of OM, respectively. Ketone, amine and organosulfate groups constituted 6%, 5%, and <1% of the average organic aerosol composition, respectively. Measurements of volatile organic compounds (VOC), including isoprene and monoterpenes from biogenic VOC (BVOC) emissions and their oxidation products (methyl-vinylketone/methacrolein, MVK/MACR), were made using co-located proton transfer reaction mass spectrometry (PTR-MS). We present chemically-specific evidence of OFG associated with BVOC emissions. Positive matrix factorization (PMF) analysis attributed 65% of the campaign OM to biogenic sources, based on the correlations of one factor to monoterpenes and MVK/MACR. The remaining fraction was attributed to anthropogenic sources based on a correlation to sulfate. The functional group composition of the biogenic factor (consisting of 32% alkane, 25% carboxylic acid, 2% organic hydroxyl, 16% ketone, and 6% amine groups) was similar to that of secondary organic aerosol (SOA) reported from the oxidation of BVOCs in laboratory chamber studies, providing evidence that the magnitude and chemical composition of biogenic SOA simulated in the laboratory is similar to that found in actual atmospheric conditions. The biogenic factor OM is also correlated to dust elements, indicating that dust may act as a non-acidic SOA sink. This role is supported by the organic functional group composition and morphology of single particles, which were analyzed by scanning transmission X-ray microscopy near edge X-ray absorption fine structure (STXM-NEXAFS).

Schwartz, R. E.; Russell, L. M.; Sjosted, S. J.; Vlasenko, A.; Slowik, J. G.; Abbatt, J. P. D.; MacDonald, A. M.; Li, S. M.; Liggio, J.; Toom-Sauntry, D.; Leaitch, W. R.

2010-02-01

18

SIMILARITY BETWEEN MAN AND LABORATORY ANIMALS IN REGIONAL PULMONARY DEPOSITION OF OZONE  

EPA Science Inventory

Predicted pulmonary ozone (O3) dose curves obtained by model analysis of the transport and removal of O3 in the lungs of guinea pigs, rabbits, and man indicate that a general similarity exists among these species in the shapes of the dose curves. An overview of the major features...

19

Embryonic Development of Cuban Gar (Atractosteus tristoechus) Under Laboratory Conditions.  

PubMed

The embryonic development of Cuban gar (Atractosteus tristoechus) was described under controlled laboratory conditions. During the whole embryogenesis seven periods were defined: the zygote (0-½ h), cleavage (¾-4 h), blastula (5-10 h), gastrula (12-20 h), segmentation (24-40 h), pharyngula (48-66 h) and hatching (72-96 h) periods. The stages were based on morphological features, generally readily identified by examination of the embryo with the dissecting stereomicroscope. Hatching occurred 96 ± 4 h after spawning at 28°C. PMID:24527771

Comabella, Y; Canabal, J; Hurtado, A; García-Galano, T

2014-12-01

20

Self-similarity of plasma networking in a broad range of length scales: From laboratory to cosmic plasmas  

NASA Astrophysics Data System (ADS)

A newly developed method of high-resolution processing, called a method of multilevel dynamical contrasting, is applied to analyze numerous data from laboratory electric discharges and observations of cosmic plasmas in a broad spectroscopic range from rf to soft x-ray images. A high degree of self-similarity of plasma structuring is found in a very broad range of length scales, from individual filaments in laboratory discharges to the structures in the universe, which resemble electric currents networking in laboratory plasmas. The results presented illustrate recently suggested [Kukushkin and Rantsev-Kartinov, Laser Part. Beams 16, 445 (1998)] generic features of networking in plasmas: (1) long-living (nonfluctuative) filamentation of electric current; (2) formation of a fractal structure made of single filament and complicated interaction of these ``fractal'' filaments; (3) formation of a percolating network that includes, in particular, formation of the ``stockings'' woven by the individual filaments.

Kukushkin, A. B.; Rantsev-Kartinov, V. A.

1999-02-01

21

Evaluation of annoyance from low frequency noise under laboratory conditions.  

PubMed

The aim of the study was to investigate the annoyance of low frequency noise (LFN) at levels normally prevailing at workplaces in control rooms and office-like areas. Two different laboratory experiments were carried out. The first experiment included 55 young volunteers and the second one comprised 70 older volunteers, categorized in terms of sensitivity to noise. The subjects listened to noise samples with different spectra, including LFNs at sound pressure level (SPL) of 45-67 dBA, and evaluated annoyance using a 100-score graphical rating scale. The subjective ratings of annoyance were compared to different noise metrics. In both the experiments, there were no differences in annoyance assessments between females and males. A significant influence of individual sensitivity to noise on annoyance rating was observed for some LFNs. Annoyance of LFN was not rated higher than annoyance from broadband noises without or with less prominent low frequencies at similar A-weighted SPLs. In both the experiments, median annoyance rating of LFN highly correlated with A-weighted SPL (L(Aeq,T)), low frequency A-weighted SPL (L(LFAeq,T)) and C-weighted SPL (L(Ceq,T)). However, it is only the two latter noise metrics (i.e. L(LFAeq,T) and L(Ceq,T)) which seem to be reliable predictors of annoyance exclusively from LFN. The young and older participants assessed similar annoyance from LFN at similar L(LFAeq,T) or L(Ceq,T) levels. Generally, over half of the subjects were predicted to be highly annoyed by LFN at the low frequency A-weighted SPL or C-weighted SPL above 62 and 83 dB, respectively. PMID:20603573

Pawlaczyk-Luszczynska, Malgorzata; Dudarewicz, Adam; Szymczak, Wieslaw; Sliwinska-Kowalska, Mariola

2010-01-01

22

Calomys laucha (Rodentia, Cricetidae): growth and breeding in laboratory conditions.  

PubMed

The husbandry and breeding of Calomys laucha (Rodentia, Cricetidae) in captivity are described. Growth curves based on body weight and length showed statistical differences between sexes after 45 days, males being heavier than females. The overall reproductive efficiency was 53.4% but birth rate was depressed during winter. Gestation length was 21 +/- 1 days and females exhibited postpartum oestrus with a 3-7 day implantation delay (51%). Litter size was 5.3 +/- 1.1 (n = 34). Pup survival at weaning was 84.9%. Mean life span in laboratory conditions was 13.5 months and a cumulative mortality of 90% was reached at 27-28 months of age. PMID:2681995

Hodara, V L; Espinosa, M B; Merani, M S; Quintans, C

1989-10-01

23

Reproduction of Omalonyx matheroni (Gastropoda: Succineidae) under laboratory conditions.  

PubMed

The life histories of succineids have received relatively little attention. To evaluate life history characteristics of Omalonyx matheroni, we studied a Brazilian population (Reserva Particular do Patrimônio Natural Feliciano Miguel Abdala, in Caratinga, Minas Gerais, Brazil) under laboratory conditions. The aims of the present study were (1) to describe in detail an appropriate rearing method; (2) to investigate the effects of different temperature and photoperiod conditions; and (3) to assess the effects of self and cross-fertilization on the reproductive biology of these mollusks. We studied the oviposition site, the time to sexual maturity and the influences of photoperiod and temperature on reproductive parameters of O. matheroni reared under laboratory conditions. We tested three combinations of temperature and photoperiod, designated A, B and C (A: 25degreeC, 24 hours of light; B: environmental conditions of temperature and photoperiod, characterized as follows: average maximum temperature=27.1 degreeC, average minimum temperature=18.3 degreeC, average day length=12.06 hours; and C: 25 degreeC, zero hours of light) and two rearing densities (I: isolated and G: grouped) on reproductive parameters (number of eggs per egg mass, number of unviable eggs per mass, egg mass incubation period, and duration of the hatching period). A total of 186 individuals and 565 egg masses were studied. Data were analyzed by Student's t-test, two-way ANOVA and Chi-Square test. Eight generations were produced (March/2004-March/2006), from 35 field specimens, 91% of 3 197 eggs hatched. The time to sexual maturity was approximately three months for individuals reared in groups or in isolation (Student's t-test: t=1.41, df=31, p=0.16); however, they differed significantly in weight (Student's t-test: t=3.6, df=31, p<0.001). Regarding the influences of temperature and photoperiod on reproductive parameters, under natural environmental conditions, individuals produced a greater number of eggs per mass (ANOVA: F2573,=84.15, p<0.001), with a longer incubation period (ANOVA: F2559=170.05, p<0.001). The extreme photoperiod conditions of 24 hours of light or zero hours of light likely imposed stress and could be related to the significant reductions in the number of eggs per mass, and egg incubation period as well as the increased synchrony in egg hatching. No correlations were observed between the number of unviable eggs per mass and the temperature, photoperiod (ANOVA: F2573=0.87, p=0.92) or rearing density (ANOVA: F1 .573=0.21, p=0.64). Individuals reared in isolation under natural conditions produced more eggs per mass and did not presented any disadvantage with respect to the variables analyzed as compared to the animals reared in groups. These results indicate that O. matheroni can successfully reproduce by selfing. PMID:23894928

Montresor, Lângia; Teixeira, Ana; Paglia, Adriano; Vidigal, Teofânia

2012-06-01

24

19 CFR 113.67 - Commercial gauger and commercial laboratory bond conditions.  

...1 2014-04-01 2014-04-01 false Commercial gauger and commercial laboratory bond conditions. 113.67 Section...BONDS Customs Bond Conditions § 113.67 Commercial gauger and commercial laboratory bond...

2014-04-01

25

Work Conditions, Mastery and Psychological Distress: Are Housework and Paid Work Contexts Conceptually Similar?  

Microsoft Academic Search

This research examined how the conditions of paid work and unpaid housework were related to women's sense of mastery, depressed mood and anxiety. The data for these analyses were taken from the American Changing Lives (ACL) survey (House, 1986). This research draws from a subsample of 992 black and non-Hispanic white women aged 24 to 59. The conditions of work

Emilio L. Lombardi; Patricia M. Ulbrich

1998-01-01

26

Life cycle of tortoise tick Hyalomma aegyptium under laboratory conditions.  

PubMed

The tortoise tick Hyalomma aegyptium has a typical three-host life-cycle. Whereas its larvae and nymphs are less host-specific feeding on a variety of tetrapods, tortoises of the genus Testudo are principal hosts of adults. Ticks retained this trait also in our study under laboratory conditions, while adults were reluctant to feed on mammalian hosts. Combination of feeding larvae and nymphs on guinea pigs and feeding of adults on Testudo marginata tortoises provided the best results. Feeding period of females was on average 25 days (range 17-44), whereas males remain after female engorgement on tortoise host. Female pre-oviposition period was 14 days (3-31), followed by 24 days of oviposition (18-29). Pre-eclosion and eclosion, both together, takes 31 days (21-43). Larvae fed 5 days (3-9), then molted to nymphs after 17 days (12-23). Feeding period of nymphs lasted 7 days (5-10), engorged nymphs molted to adults after 24 days (19-26). Sex ratio of laboratory hatched H. aegyptium was nearly equal (1:1.09). The average weight of engorged female was 0.95 (0.72-1.12) g. The average number of laid eggs was 6,900 (6,524-7,532) per female, it was significantly correlated with weight of engorged female. Only 2.8% of engorged larvae and 1.8% of engorged nymphs remained un-molted and died. Despite the use of natural host species, feeding success of females reached only 45%. The whole life-cycle was completed within 147 days (98-215). PMID:21431927

Siroký, Pavel; Erhart, Jan; Petrželková, Klára J; Kamler, Martin

2011-07-01

27

Investigation of influence of hypomagnetic conditions closely similar to interplanetary magnetic filed on behavioral and vegetative reactions of higher mammals  

NASA Astrophysics Data System (ADS)

To study the influence of long being under reduced magnetic field on behavioral and vegetative reactions of higher mammals the white rat males were put into the 700-1000 times reduced geomagnetic field (50-70 nT) for 25 days. Such field was obtained by using automatic compensation of the horizontal and vertical components of the GMF at a frequencies up to 10 Hz by means of solenoids of the experimental magnetic system. Control animals were located in the same room under usual laboratory GMF conditions (52 uT). Two days before the experiment the behavioral reactions were studied in the "open field" by means of a set of tests, characterizing the level of emotionality, moving and orientational-investigative activities of the animals under conditions of unimpeded behavior. 60 white underbred rat males with the initial body mass of 200 g were divided into three clusters. Animals with average indices were selected for the experiment. We have judged behavioral reaction disturbances of the rats under hypomagnetic conditions using videotape recordings carried out in the entire course of the chronic experiment. According to the obtained results during the period of maximum activity (from 230 to 330 a.m.) the number of interrelations between the individuals increased appreciably for experimental rats including interrelations with aggressive character. This was real during all 25 days of observation. We observed a certain dynamics of this index differed from that of the control group. We have also analyzed the final period of observation from the 21th to the 25th days. In this period we studied the 24 hours' dynamics of interrelations which were noted during 5 minutes in every hour around the clock. In the control group the number of interrelation was at a constantly low level. For experimental animals the number of interrelations was higher in the night hours than in the day ones. Moreover it exceeded the similar indexes observed from the 1st to the 20th day. For example from 300 to 305 a.m. on the 23th day we recorded 27 contacts of aggressive character between the individuals. So, in hypomagnetic field conditions the irritability of the animals' central nervous system grows, that expresses itself in the increase of contacts of aggressive and non-aggressive character between the individuals. Also we have carried out the Spirman correlation analysis between studied indices of moving activity and chemiluminescence of blood plasma and urine, electrolytic composition of urine and muscles. For control animals the quantity of correlation connections between electrolyte concentrations in studied substrata was higher than for experimental animals. The physiological sense of these correlation connections is discussed.

Krivova, Natalie; Trukhanov, Kiril; Zamotshina, Tatyana; Zaeva, Olga; Khodanovich, Marina; Misina, Tatyana; Tukhvatulin, Ravil; Suhko, Valery

28

Reproducibility of pulmonary function tests under laboratory and field conditions  

Microsoft Academic Search

The reproducibility of pulmonary function tests in the laboratory and in a mobile field survey vehicle has been studied. Groups of laboratory workers were studied at base and a random sample of 38 coalminers was examined in the mobile laboratory. The intra-subject variability of some newer tests of lung function, including closing volume and maximum flow at low lung volumes,

R G Love; M D Attfield; K D Isles

1980-01-01

29

Drought survival in Dactylis glomerata and Festuca arundinacea under similar rooting conditions in tubes  

Microsoft Academic Search

Drought survival in perennial forage plants involves different adaptative responses such as delay of dehydration through water uptake, limitation of water loss and tolerance of tissues to dessication. To compare the importance of these responses in contrasting cultivars of forage grasses at the whole plant level, we carried out two experiments under glasshouse conditions. Plants of cocksfoot (Dactylis glomerata L.)

F. Volaire; F. Lelièvre

2001-01-01

30

The Design of Research Laboratories. Part I: A General Assessment. Part II: Air Conditioning and Conditioned Rooms.  

ERIC Educational Resources Information Center

Design factors in the planning of research laboratories are described which include--(1) location, (2) future expansion, (3) internal flexibility, (4) provision of services, (5) laboratory furnishing, (6) internal traffic, (7) space requirements, and (8) building costs. A second part discusses air-conditioning and conditioned rooms--(1)…

Legget, R. F.; Hutcheon, N. B.

31

DO TIE LABORATORY BASED METHODS REALLY REFLECT FIELD CONDITIONS  

EPA Science Inventory

Sediment Toxicity Identification and Evaluation (TIE) methods have been developed for both interstitial waters and whole sediments. These relatively simple laboratory methods are designed to identify specific toxicants or classes of toxicants in sediments; however, the question ...

32

Interoceptive conditioning with nicotine using extinction and re-extinction to assess stimulus similarity with bupropion.  

PubMed

Bupropion is an atypical antidepressant that increases long-term quit rates of tobacco smokers. A better understanding of the relation between nicotine and this first-line medication may provide insight into improving treatment. For all experiments, rats first had nicotine (0.4 mg base/kg) and saline session intermixed; intermittent access to sucrose only occurred on nicotine session. Nicotine in this protocol comes to differentially control "anticipatory" dipper entries. To more closely examine the overlap in the interoceptive stimulus effects of nicotine and bupropion, we assessed whether subsequent prolonged and repeated non-reinforced (extinction) sessions with the bupropion stimulus could weaken responding to nicotine (i.e., transfer of extinction). We also examined whether retraining the discrimination after initial extinction and then conducting extinction again (i.e., re-extinction) with bupropion would affect responding. We found that bupropion (20 and 30 mg/kg) fully substituted for the nicotine stimulus in repeated 20-min extinction sessions. The extent of substitution in extinction did not necessarily predict performance in the transfer test (e.g., nicotine responding unchanged after extinction with 20 mg/kg bupropion). Generalization of extinction back to nicotine was not seen with 20 mg/kg bupropion even after increasing the number of extinction session from 6 to 24. Finally, there was evidence that learning in the initial extinction phase was retained in the re-extinction phase for nicotine and bupropion. These findings indicate that learning involving the nicotine stimuli are complex and that assessment approach for stimulus similarity changes conclusions regarding substitution by bupropion. Further research will be needed to identify whether such differences may be related to different facets of nicotine dependence and/or its treatment. PMID:25080073

Charntikov, Sergios; deWit, Nicole R; Bevins, Rick A

2014-11-01

33

42 CFR 493.1481 - Condition: Laboratories performing high complexity testing; cytotechnologist.  

Code of Federal Regulations, 2013 CFR

... § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist. For the subspecialty of cytology, the laboratory must have a sufficient number of cytotechnologists who meet the qualifications specified in § 493.1483 to...

2013-10-01

34

42 CFR 493.1481 - Condition: Laboratories performing high complexity testing; cytotechnologist.  

Code of Federal Regulations, 2011 CFR

... § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist. For the subspecialty of cytology, the laboratory must have a sufficient number of cytotechnologists who meet the qualifications specified in § 493.1483 to...

2011-10-01

35

42 CFR 493.1481 - Condition: Laboratories performing high complexity testing; cytotechnologist.  

Code of Federal Regulations, 2012 CFR

... § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist. For the subspecialty of cytology, the laboratory must have a sufficient number of cytotechnologists who meet the qualifications specified in § 493.1483 to...

2012-10-01

36

42 CFR 493.1481 - Condition: Laboratories performing high complexity testing; cytotechnologist.  

Code of Federal Regulations, 2010 CFR

... § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist. For the subspecialty of cytology, the laboratory must have a sufficient number of cytotechnologists who meet the qualifications specified in § 493.1483 to...

2010-10-01

37

Laboratory astrochemistry: studying molecules under inter- and circumstellar conditions  

Microsoft Academic Search

In this paper, we outline recent developments in and the growing need for laboratory astrochemical measurements. After a short review on experimental methods, we focus primarily upon the utility of multi-electrode ion trapping methods for addressing key problems in reaction dynamics and their applications towards gaining a better understanding of the physicochemical driving forces behind compositional development in interstellar and

D. Gerlich; M. Smith

2006-01-01

38

Exploring the nature of collisionless shocks under laboratory conditions.  

PubMed

Collisionless shocks are pervasive in astrophysics and they are critical to understand cosmic ray acceleration. Laboratory experiments with intense lasers are now opening the way to explore and characterise the underlying microphysics, which determine the acceleration process of collisionless shocks. We determine the shock character - electrostatic or electromagnetic - based on the stability of electrostatic shocks to transverse electromagnetic fluctuations as a function of the electron temperature and flow velocity of the plasma components, and we compare the analytical model with particle-in-cell simulations. By making the connection with the laser parameters driving the plasma flows, we demonstrate that shocks with different and distinct underlying microphysics can be explored in the laboratory with state-of-the-art laser systems. PMID:24488212

Stockem, A; Fiuza, F; Bret, A; Fonseca, R A; Silva, L O

2014-01-01

39

Exploring the nature of collisionless shocks under laboratory conditions  

PubMed Central

Collisionless shocks are pervasive in astrophysics and they are critical to understand cosmic ray acceleration. Laboratory experiments with intense lasers are now opening the way to explore and characterise the underlying microphysics, which determine the acceleration process of collisionless shocks. We determine the shock character – electrostatic or electromagnetic – based on the stability of electrostatic shocks to transverse electromagnetic fluctuations as a function of the electron temperature and flow velocity of the plasma components, and we compare the analytical model with particle-in-cell simulations. By making the connection with the laser parameters driving the plasma flows, we demonstrate that shocks with different and distinct underlying microphysics can be explored in the laboratory with state-of-the-art laser systems. PMID:24488212

Stockem, A.; Fiuza, F.; Bret, A.; Fonseca, R. A.; Silva, L. O.

2014-01-01

40

[Microbial growth on bitumen and chlorcaoutchouc under laboratory conditions (author's transl)].  

PubMed

Formerly published examinations of coating materials for drinking water reservoirs under working conditions were extended to those under laboratory standard. The tests of bitumen, chlorcaoutchouc, asbestos cement and polyacryl delivered results comparable to those achieved under working conditions. PMID:735574

Schoenen, D; Dott, W

1978-11-01

41

Laboratory investigation of capillary trapping under mixed-wet conditions  

NASA Astrophysics Data System (ADS)

Remaining oil saturation established by waterflooding was measured in Indiana limestone in its original, water-wet state and under mixed-wet conditions established by adding organic acid to the oil phase. The porous plate technique was used to establish initial oil saturations ranging from Snwi = 0.23 to 0.93 under capillary-dominated conditions. For water-wet conditions, the residual oil saturation increased linearly with its initial saturation. In contrast, the remaining oil saturation under mixed-wet conditions, Snw, displayed three distinct regimes. First, Snw increased with its initial saturation up to Snwi = 0.58. Next, Snw decreased from Snwi = 0.58 to 0.76. Finally, Snw increased again as Snwi approached one. The nonmonotonic dependence of Snw on Snwi at Snwi > 0.5 is well described by a concave-up quadratic function, and may be a salient feature of mixed-wet rocks.

Tanino, Y.; Blunt, M. J.

2013-07-01

42

Hot-Water and Steamflood Laboratory Experiments Under Reservoir Conditions  

Microsoft Academic Search

Hot waterfloods at four temperatures (between 30 and 240°C (86 and 464°F)) and a steamflood were performed on the same porous medium (compact silt) under reservoir conditions. Dynamic isothermal displacements were interpreted with a thermal simulator, taking into account capillary end effects. The corresponding oil\\/water relative permeability curves were obtained by matching observed pressure drop and oil production. Results show

L. Quettier; B. Corre

1988-01-01

43

Hot water and steamflood laboratory experiments under reservoir conditions  

Microsoft Academic Search

Hot waterfloods at four temperatures (between 30 and 240°C) and a steamflood were performed on the same porous medium (compacted silt) under reservoir conditions. Dynamic isothermal displacements were interpreted with a thermal simulator taking into account capillary end effects. The corresponding oil-water relative permeabilities curves were obtained by matching observed pressure drop and oil production. Results show that temperature influences

L. Quettier; B. Corre

1986-01-01

44

Communities of different plant diversity respond similarly to drought stress: experimental evidence from field non-weeded and greenhouse conditions  

NASA Astrophysics Data System (ADS)

Accelerating rate of species loss has prompted researchers to study the role of species diversity in processes that control ecosystem functioning. Although negative impact of species loss has been documented, the evidence concerning its impact on ecosystem stability is still limited. Here, we studied the effects of declining species and functional diversity on plant community responses to drought in the field (open to weed colonization) and greenhouse conditions. Both species and functional diversity positively affected the average yields of field communities. However, this pattern was similar in both drought-stressed and control plots. No effect of diversity on community resistance, biomass recovery after drought and resilience was found because drought reduced biomass production similarly at each level of diversity by approximately 30 %. The use of dissimilarity (characterized by Euclidean distance) revealed higher variation under changing environments (drought-stressed vs. control) in more diverse communities compared to less species-rich assemblages. In the greenhouse experiment, the effect of species diversity affected community resistance, indicating that more diverse communities suffered more from drought than species-poor ones. We conclude that our study did not support the insurance hypothesis (stability properties of a community should increase with species richness) because species diversity had an equivocal effect on ecosystem resistance and resilience in an environment held under non-weeded practice, regardless of the positive relationship between sown species diversity and community biomass production. More species-rich communities were less resistant against drought-stressed conditions than species-poor ones grown in greenhouse conditions.

Lanta, Vojt?ch; Doležal, Ji?í; Zemková, Lenka; Lepš, Jan

2012-06-01

45

Extracting phosphoric iron under laboratorial conditions smelting bog iron ores  

NASA Astrophysics Data System (ADS)

In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well.

Török, B.; Thiele, A.

2013-12-01

46

A Laboratory Study to Determine the Effect of Partially Saturated Conditions on Relaxation  

NASA Astrophysics Data System (ADS)

Nuclear magnetic resonance, NMR, is a geophysical method that is sensitive to the quantity as well as the physical and chemical environments of hydrogen in porous media. In near-surface geophysics, NMR is used to determine water content and estimate pore size distribution in the top 100 m of the surface. The interpretation of NMR data in near-surface geophysics generally assumes fully saturated conditions exist in the measured volume; however, little is known about the effect partially saturated conditions have on the interpretation NMR data. In this laboratory study, we examine the effect of partially saturated conditions on measured NMR parameters. The NMR experiment consists of measuring a multi-exponential decay of magnetization after an oscillating magnetic field is applied to a sample. The multi-exponential decay is characterized by the initial amplitude, M0, and the mean log decay time, T2ml. The initial amplitude of this decay, M0, is proportional to the total water content present in a sample. In fully saturated conditions, the T2ml value is related to the surface-area-to-volume ratio. To understand the effect of partially saturated conditions on the interpretation of NMR data, we have collected NMR measurements on samples at different saturations during periods of wetting and drying and determined M0 and T2ml. We observe that T2ml increases with saturation, and M0 is linearly proportional to water content. In addition, the T2ml values at similar water contents were are shorter under drying than wetting conditions. We infer that the observed differences in the T2ml values are due to changes in the geometric distribution of water within the pore space of the sample. The results from this study will help to improve the interpretation of NMR measurements in partially saturated porous media.

Falzone, S.; Keating, K.

2010-12-01

47

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and Earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically-derived microwave absorption properties for such atmospheric constituents, or laboratory measurements of such properties under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often lead to significant misinterpretation of available opacity data. Steffes and Eshleman showed that under environmental conditions corresponding to the middle atmosphere of Venus, the microwave absorption due to atmospheric SO2 was 50 percent greater than that calculated from Van Vleck-Weiskopff theory. Similarly, the opacity from gaseous H2SO4 was found to be a factor of 7 greater than theoretically predicted for conditions of the Venus middle atmosphere. The recognition of the need to make such measurements over a range of temperatures and pressures which correspond to the periapsis altitudes of radio occultation experiments, and over a range of frequencies which correspond to both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements.

Steffes, P. G.

1985-01-01

48

Basic Demography of Caenorhabditis remanei Cultured under Standard Laboratory Conditions  

PubMed Central

Species of the Caenorhabditis genus have been used as model systems in genetics and molecular research for more than 30 years. Despite this, basic information about their demography, in the wild and in the lab, has remained unknown until very recently. Here, we provide for the first time a closely quantified life-cycle of the gonochoristic nematode C. remanei. Using C. elegans protocols, modified for an outcrossing nematode, we estimated the basic demography for individuals of two strains (JU724 and MY12-G) which were recently isolated from the wild. We used a half-sib breeding design to estimate the phenotypic variance of traits of related (within line) and unrelated individuals (between lines) of the two strains cultured in a common environment in the lab. Comparisons between these strains showed that JU724 was characterized by significantly lower overall lifetime fecundity and by differences in age-specific fecundity relative to MY12-G, but there were no differences in their life expectancy and reproductive lifespan. We found high phenotypic variance among all traits. The variance within lines was relatively high compared to the low variation between lines. We suggest this could be the result of high gene flow in these wild-type strains. Finally, comparisons between species suggest that, despite the differences in reproductive strategies (i.e., sex ratios, lifetime fecundity), C. remanei has developmental time similar to the hermaphroditic N2 strain of C. elegans. PMID:19440256

Lindstrom, Jan; Haydon, Daniel T.

2008-01-01

49

Cues Paired with either Rapid or Slower Self-Administered Cocaine Injections Acquire Similar Conditioned Rewarding Properties  

PubMed Central

The faster drugs of abuse reach the brain, the more addictive they can be. It is not known why this is. Environmental stimuli associated with drugs can promote the development and persistence of addiction by invigorating and precipitating drug-seeking behaviour. We determined, therefore, whether cues associated with the self-administration of rapidly delivered cocaine (injected intravenously over 5 versus 90 seconds) would acquire greater conditioned rewarding properties, as assessed by the performance of an operant response reinforced solely by the cues. Rats nose-poked for intravenous cocaine infusions delivered either over 5 or 90 seconds. Discrete visual cues accompanied each infusion. The rats could then press a lever to obtain the cues—now a conditioned reward—or an inactive lever. Rats in both the 5- and 90-second groups pressed more on the active versus inactive lever following extensive (24 sessions) but not following limited (3 sessions) self-administration training. There were no group differences in this behaviour. Following withdrawal from cocaine self-administration, lever discrimination progressively abated in both groups and was lost by withdrawal day 30. However, the rewarding properties of the cues were not “forgotten” because on withdrawal days 32–33, amphetamine selectively enhanced active-lever pressing, and did so to a similar extent in both groups. Thus, cues paired with rapid or slower cocaine delivery acquire similar conditioned rewarding properties. We conclude, therefore, that the rapid delivery of cocaine to the brain promotes addiction by mechanisms that might not involve a greater ability of drug cues to control behaviour. PMID:22039496

Samaha, Anne-Noel; Minogianis, Ellie-Anna; Nachar, Walid

2011-01-01

50

Gas exchange responses of Chesapeake Bay tidal marsh species under field and laboratory conditions  

Microsoft Academic Search

Laboratory and field gas exchange measurements were made on C3 (Scirpus olneyi Gray) and C4 (Spartina patens (Ait.) Mahl., Distichlis spicata (L.) Green) species from an irregularly flooded tidal marsh on the Chesapeake Bay. Laboratory measurements were made on plants grown from root stocks that were transplanted to a greenhouse and grown under high light and high nutrient conditions. The

T. M. DeJong; B. G. Drake; R. W. Pearcy

1982-01-01

51

Effects of ethanol on punished and unpunished responding under conditions of equated reinforcement rates and similar response rates  

SciTech Connect

Lever pressing by pairs of rats was maintained under random-ratio and yoked random-interval schedules of food presentation. The interreinforcement intervals generated under the ratio schedule comprised the interval values for the second (yoked) subject. This procedure yielded roughly equal rates of food presentation for each subject. A random-ratio schedule of shock presentation was added for the rats responding under the ratio schedule of food presentation. This manipulation resulted in similar rates of punished and unpunished responding across subject pairs. Low doses of ethanol administered i.p. 30 min prior to selected experimental sessions had relatively little effect upon punished responding, while larger doses resulted in decreases in punished responding. Similar effects were seen when these doses were given immediately prior to selected sessions, although decreases in punished responding were sometimes seen at lower doses under these conditions. Using this procedure, drugs such as pentobarbital and chlordiazepoxide have been shown increase punished responding. Thus, within the context of this arrangement, ethanol did not produce anti-conflict effects. These data imply that anti-conflict effects of ethanol sometimes obtained may depend critically upon the particular procedure used. The important feature(s) necessary for these effects have yet to be precisely characterized.

Pitts, R.C.; Dworkin, S.I. (Bowman Gray School of Medicine, Winston-Salem, NC (United States)); Lewis, M.J. (Howard Univ., Washington, DC (United States))

1991-03-11

52

A comprehensive approach to studies of porous media (rocks) using a laboratory spectrometer and logging tool with similar operating characteristics.  

PubMed

The value of NMR spectrometry as a way to understand the porosity and permeability of rocks is well documented. Other more esoteric parameters, such as restrictive diffusion, grain size distribution, and fluid viscosities have received less notice but are also available from the NMR measurements as laboratory studies have shown. With the introduction of gradient field spin-echo NMR well logging, all of these parameters become available in a routine way. To accomplish the goal of having a well log that systematically provides this complete array of NMR answers requires consideration of the measurement principles that can be applied. Magnetic field strength and the relative merits of gradient versus homogeneous magnetic fields methods, as well as the limitations presented by the well bore and wireline systems are a few examples of the factors that must be considered. As important, to the end user, is being provided a definitive link between the well logging response and laboratory measurements on rock samples that prove the meaning of the log. This is ideally accomplished when the laboratory measurements are attained using an apparatus that has the same operating characteristics as the log. For most well logging systems this is seldom accomplished to the degree desired, but it is readily attainable with NMR technologies. The consideration of these factors and the features and benefits of having such a capability are the focus of this paper. The technical attributes of such a comprehensive system, the Numar Corporation's "MRIL" and "CoreSpec1000", plus actual examples of laboratory and well bore data are provided to show the value of such an approach. PMID:8170320

Taicher, Z; Coates, G; Gitartz, Y; Berman, L

1994-01-01

53

Kinetics of phase separation in the driven lattice gas: Self-similar pattern growth under anisotropic nonequilibrium conditions  

E-print Network

,2,7 this segregation, as well as similar processes in actual mixtures, exhibit time self-similarity. This propertyKinetics of phase separation in the driven lattice gas: Self-similar pattern growth under except at some very early perhaps unobservable time. This implies a sort of self-similarity, namely

Marro, Joaquín

54

40 CFR Appendix G to Subpart A of... - UNEP Recommendations for Conditions Applied to Exemption for Essential Laboratory and Analytical...  

Code of Federal Regulations, 2013 CFR

... UNEP Recommendations for Conditions Applied to Exemption for Essential Laboratory...UNEP Recommendations for Conditions Applied to Exemption for Essential Laboratory...diluents, or carriers for chemical analysis; biochemical research; inert...

2013-07-01

55

19 CFR 113.67 - Commercial gauger and commercial laboratory bond conditions.  

Code of Federal Regulations, 2010 CFR

...condition shall be based on the quantity and value of the merchandise as determined by Customs and that value as used in these provisions means value as determined under 19 U.S.C. 1401a. Commercial Laboratory Bond Conditions (b)...

2010-04-01

56

Kinetics of phase separation in the driven lattice gas:?Self-similar pattern growth under anisotropic nonequilibrium conditions  

NASA Astrophysics Data System (ADS)

The driven lattice gas (DLG) evolving at low temperature helps understand the kinetics of pattern formation in unstable mixtures under anisotropic conditions. We here develop a simple theoretical description of kinetics in Monte Carlo simulations of the DLG. A Langevin continuum analog is also studied which is shown to exhibit the same behavior. We demonstrate that pattern growth is mainly a consequence of single-particle processes and that, after a short transient time, in which a surface evaporation/condensation mechanism is important, hole diffusion in the bulk becomes dominant. Consequently, there is a unique relevant length that behaves l(t)˜t1/3 for macroscopic systems except at some very early (perhaps unobservable) time. This implies a sort of self-similarity, namely, the spatial pattern looks alike, but for a (nontrivial) change of scale at different times. We also characterize the structure factor, in which we identify Guinier and Porod regions, and its scaling form with both time and size. The underlying anisotropy turns out to be essential in determining the macroscopically emergent peculiar behavior.

Hurtado, P. I.; Marro, J.; Garrido, P. L.; Albano, E. V.

2003-01-01

57

Equivalent inbreeding depression under laboratory and field conditions in a tree-hole-breeding mosquito.  

PubMed Central

Understanding the consequences of inbreeding has important implications for a wide variety of topics in population biology. However, most studies quantifying the effects of inbreeding are performed under artificial farm, greenhouse, laboratory or zoo conditions. Although several authors have argued that the deleterious effects of inbreeding (inbreeding depression) are likely to be more severe under natural field conditions than in artificial experimental environments, these arguments are usually speculative or based on indirect comparisons. We quantified the effects of inbreeding on fitness traits in a tree-hole-breeding mosquito Aedes geniculatus) under near-optimal laboratory conditions and in three natural tree holes. Our index of fitness (Ro) was lower in the field than in the laboratory and declined due to inbreeding in both However, environments, we found no significant interactions between inbreeding depression and environmental conditions. In both the field and laboratory a 10% increase in the inbreeding coefflicient (F) led to a 12-15) decline in fitness (Ro) These results suggest that inbreeding depression will not necessarily be more extreme under natural field conditions than in the laboratory. PMID:11075705

Armbruster, P; Hutchinson, R A; Linvell, T

2000-01-01

58

Hydrologic conditions at the Idaho National Engineering Laboratory, Idaho, emphasis; 1974-1978  

USGS Publications Warehouse

Aqueous chemical and radioactive wastes have been discharged to shallow ponds and to shallow or deep wells on the Idaho National Engineering Laboratory (INEL) since 1952 and has affected the quality of the ground water in the underlying Snake River Plain aquifer. Ongoing studies conducted from 1974 through 1978 have shown the perpetuation of a perched ground-water zone in the basalt underlying the waste disposal ponds at the INEL 's Test Reactor Area and of several waste plumes in the regional aquifer created by deep well disposal at the Idaho Chemical Processing Plant (ICPP). The perched zone contains tritium, chromium-51, cobalt-60, strontium-90, and several nonradioactive chemicals. Tritium has formed the largest waste plume south of the ICPP, and accounts for 95 percent of the total radioacticity disposed of through the ICPP disposal well. Waste plumes with similar configurations and flowpaths contain sodium, chloride, and nitrate. Strontium-90, iodine-129, and cesium-137 are also discharged through the well but they are sorbed from solution as they move through the aquifer or are discharged in very small quantities. Strontium-90 and iodine-129 have formed small waste plumes and cesium-137 is not detectable in ground-water samples. Radionuclide plume size and concentrations therein are controlled by aquifer flow conditions, the quantity discharged, radioactive decay, sorption, dilution by dispersion, and perhaps other chemical reactions. Chemical wastes are subject to the same processes except for radioactive decay. (USGS)

Barraclough, Jack T.; Lewis, Barney D.; Jensen, Rodger G.

1981-01-01

59

Interoceptive conditioning with the nicotine stimulus: extinction learning as a method for assessing stimulus similarity across doses.  

PubMed

Interoceptive conditioning involving the nicotine stimulus likely contributes to chronic tobacco use. To better understand the nature of this interoceptive conditioning, we compared generalization during repeated extinction with generalization in a 'transfer of extinction' test using a wide range of test doses. Rats were first trained in the discriminated goal-tracking task in which nicotine (0.2 or 0.4 mg/kg), but not saline, was paired with repeated intermittent access to sucrose. Across sessions, nicotine acquired control of approach behavior directed at the location of previous sucrose deliveries. Extinction followed with eight 20-min sessions without sucrose access; extinction doses of nicotine ranged from 0.05 to 0.6 mg/kg. In rats trained with 0.4 mg/kg, the 0.1, 0.2, and 0.6 mg/kg doses evoked comparable responding across extinction sessions; substitution was only partial at 0.05 and 0.075 mg/kg (i.e. above saline controls, but less than the training dose). With the 0.2 mg/kg training dose, complete generalization was seen only at the 0.1 and 0.4 mg/kg doses. After extinction, rats were given a transfer test with their training dose. Rats trained with 0.4 mg/kg showed full transfer of extinction learning with 0.1, 0.2, and 0.6 mg/kg (i.e. responding comparable with extinction with the training dose). Partial transfer was observed at 0.075 mg/kg. With the 0.2 mg/kg nicotine dose, only 0.4 mg/kg fully generalized; 0.075, 0.1, and 0.6 mg/kg showed partial transfer. Extinction with 0.05 mg/kg dose did not show transfer to either training dose. These findings indicated that conclusions regarding stimulus similarity across nicotine doses can vary with testing protocol. PMID:23263484

Polewan, Robert J; Savala, Stephanie A; Bevins, Rick A

2013-02-01

60

Assessment of biodegradability of plastics under simulated composting conditions in a laboratory test system  

Microsoft Academic Search

An automated laboratory-scale test system was developed for measuring the aerobic biodegradability of degradable plastics under simulated composting conditions. Biodegradation was monitored by measuring microbial carbon dioxide formation and oxygen consumption. Completeness of biodegradation was assessed in an aquatic test by conducting a carbon mass balance. The percentage of plastic carbon degraded to carbon dioxide, biomass and water-soluble byproducts were

Andreas Starnecker; Michael Menner

1996-01-01

61

Laboratory Investigation of the HV Insulator Contamination Process under Winter Conditions  

Microsoft Academic Search

This paper describes an experimental study of the contamination process on AC energized high voltage insulators under winter conditions. An open loop wind tunnel is installed inside a climate chamber and is operated with a kaolin powder generator and NaCl salt injection system. Through systematic laboratory investigations, the variations of salt deposit density (SDD) with the wind speed were analyzed.

N. Ravelomanantsoa; M. Farzaneh; W. A. Chisholm

2008-01-01

62

Organics on Mars: Laboratory studies of organic material under simulated martian conditions  

Microsoft Academic Search

The search for organic molecules and traces of life on Mars has been a major topic in planetary science for several decades, and is the future perspective of several missions to Mars. In order to determine where and what those missions should be looking for, laboratory experiments under simulated Mars conditions have been performed. This thesis describes the effects of

Inge Loes ten Kate

2006-01-01

63

Lawrence Berkeley National Laboratory report LBNL-52164 Conditional and Opposed Reaction Path Diagrams  

E-print Network

Lawrence Berkeley National Laboratory report LBNL-52164 Conditional and Opposed Reaction Path address: jfgrcar@lbl.gov keywords: Burke-Schumann flames, fluid-chemistry interactions, reaction path has been computed and to draw conclusions about the underlying reaction mechanisms." This paper

64

Manganese Uptake By Facultative and Obligate Wetland Plants Under Laboratory Conditions  

Microsoft Academic Search

The effect of initial concentrations of manganese on the overall removal efficiency of Mn by wool grass, soft rush, broad leaved cattail and soft stem bulrush plants was investigated under laboratory conditions. The translocation of Mn in the roots, stems, leaves and flowers of each plant species was determined and the fraction of Mn removed by precipitation was calculated. The

A. E. Ghaly; A. Snow; M. Kamal

2008-01-01

65

Reproduction, development and habits of the large turkey louse Chelopistes meleagridis (Phthiraptera: Ischnocera) under laboratory conditions.  

PubMed

The bionomy of Chelopistes meleagridis off the host was observed with the aim of better understanding the aspects of this species' life cycle. For this purpose, C. meleagridis adults were collected and maintained under controlled conditions to reproduce (35°C and RH > 80%), with turkey feathers as the food source. From the offspring of these lice, the development of 150 individuals was observed from the egg to the adult phase. These eggs were divided into two groups of 75 each. After hatching, one group was given a diet composed of feathers while the other received feathers plus skin of the host turkey (Meleagris gallopavo). The "feather + skin" diet resulted in the greatest number of adults, so this diet was given to the next generation of lice reared in vitro, starting from the first instar, to observe their fertility, fecundity and longevity. High reproduction rates were found in relation to other lice of the Ischnocera sub-order, particularly the number of eggs per day and number of eggs produced per female over the lifetime (means of 2.54 and 26.61 eggs, respectively, for wild females and 2.11 and 29.33 eggs for laboratory-reared females). The inclusion of skin in the diet was a determining factor for development to the adult stage, since 48% of the lice fed this diet reached that stage, versus 1.3% that reached maturity fed only with feathers. The development time of the males and females was similar (mean of 29.38 days), without any difference in the sexual proportion of the adults. PMID:25296223

Maturano, R; Daemon, E

2014-08-01

66

Effects of multiple contexts and context similarity on the renewal of extinguished conditioned behaviour in an ABA design with humans  

Microsoft Academic Search

The ABA renewal procedure involves pairing a conditional stimulus (CS) and an unconditional stimulus (US) in one context (A), presenting extinction trials of the CS alone in a second context (B), and nonreinforced test trials of the CS in the acquisition context (A). The renewal of extinguished conditioned behaviour is observed during test. The current study tested the effects of

Siavash Bandarian Balooch; David L. Neumann

67

Effects of Multiple Contexts and Context Similarity on the Renewal of Extinguished Conditioned Behaviour in an ABA Design with Humans  

ERIC Educational Resources Information Center

The ABA renewal procedure involves pairing a conditional stimulus (CS) and an unconditional stimulus (US) in one context (A), presenting extinction trials of the CS alone in a second context (B), and nonreinforced test trials of the CS in the acquisition context (A). The renewal of extinguished conditioned behaviour is observed during test. The…

Balooch, Siavash Bandarian; Neumann, David L.

2011-01-01

68

Detection of conspecific alarm cues by juvenile salmonids under neutral and weakly acidic conditions: laboratory and field tests.  

PubMed

A variety of fishes possess damage-released chemical alarm cues, which play a critical role in the detection and avoidance of potential predation threats. Recently, we have demonstrated that the ability of fathead minnows ( Pimephales promelas) and finescale dace ( Phoxinus neogaeus) to detect and respond to conspecific alarm cues is significantly reduced under weakly acidic conditions (pH 6.0). Rainbow trout ( Oncorhynchus mykiss) and brook charr ( Salvelinus fontinalis) possess an analogous alarm cue system. However, it is unknown if the trout alarm cue system is likewise affected by relatively small changes in pH. In addition, previous studies have not verified this phenomenon under natural conditions. We conducted laboratory and field trials to examine the potential effects of acute exposure to weakly acidic (pH 6.0) conditions on the detection and response of conspecific alarm cues by juvenile trout. Our laboratory results demonstrate that while juvenile rainbow trout exhibit significant increases in antipredator behaviour under normal pH conditions (pH 7.0-7.2), they do not respond to the presence of conspecific chemical alarm cues (i.e. response is not different from controls) under weakly acidic conditions. Similarly, a wild strain of brook charr in their natural streams near Sudbury, Ontario, failed to detect conspecific alarm cues in a weakly acidic stream (mean pH 6.11) while they responded to these cues in a neutral stream (mean pH of 6.88). This is the first demonstration that relatively small changes in ambient pH can influence alarm responses under natural conditions. These data suggest significant, sub-lethal effects of acid precipitation on natural waterways. PMID:14758533

Leduc, Antoine O H C; Kelly, Jocelyn M; E Brown, Grant

2004-04-01

69

The Similarities and Diversities of Signal Pathways Leading to Consolidation of Conditioning and Consolidation of Extinction of Fear Memory  

Microsoft Academic Search

It is generally believed that consolidation of long-term memory requires activation of protein kinases, transcription of genes, and new protein synthesis. However, little is known about the signal cascades involved in the extinction of memory, which occurs when the conditioned stimulus is no longer followed by the unconditioned stimulus. Here, we show for the first time that an intra-amygdala injection

Chih-Hung Lin; Shiu-Hwa Yeh; Hsin-Yi Lu; Po-Wu Gean

2003-01-01

70

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and Earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorping properties of potential constituents is available. The use of theoretically derived microwave absorption properties for such atmospheric constituents, or laboratory measurements of such properties under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. Laboratory measurement of the microwave properties of atmospheric gases under simulated conditions for the outer planets were conducted. Results of these measurements are discussed.

Steffes, Paul G.

1987-01-01

71

Metolachlor persistence in laboratory and field soils under Indian tropical conditions  

Microsoft Academic Search

Metolachlor [2?chloro?N?(2?methoxy?1?methylethyl)?2'?ethyl?6'?methyl acetanilide] dissipation under both field and laboratory conditions were studied during summer season in an Indian soil. Metolachlor was found to have moderate persistence with a half?life of 27 days in field. The herbicide got leached down to 15–30 cm soil layer and residues were found up to harvest day of the sunflower crop in both 0–15 cm

D. Sanyal; N. T. Yaduraju; G. Kulshrestha

2000-01-01

72

Degradation of fipronil under laboratory conditions in a tropical soil from sirinhaém pernambuco, Brazil  

Microsoft Academic Search

The objective of this research was to assess the degradation of fipronil [5-amino-1-(2,6-dichloro-?,?,? -trifluoro-p-tolyl)-4-trifluoromethylsulfinylpyrazole-3-carbonitrile] in soils from sugar cane fields in Northeastern Brazil. Degradation experiments were carried out under laboratory conditions (controlled temperature and in the dark), where sterile and non-sterile soils (Ustoxs) were incubated [under moisture content of 55% of the water holding capacity (WHC)] and analyzed for fipronil

Carmem S. M. Masutti; Ahmet R. Mermut

2007-01-01

73

Acetochlor mineralization and fate of its two major metabolites in two soils under laboratory conditions  

Microsoft Academic Search

The degradation of the herbicide acetochlor, in a neoluvisol and in a calcosol were studied as a function of depth (0–25cm and 25–50cm) and temperature (25°C and 15°C) under controlled laboratory conditions during 58 and 90 days, respectively. The surface and sub-surface soil samples were respectively spiked with 1 and 0.01mgkg?1 of 14C-acetochlor, the concentrations observed in previous field monitoring.

Marie-Christine Dictor; Nicole Baran; Anne Gautier; Christophe Mouvet

2008-01-01

74

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for the Venus middle atmosphere (1 to 6 atm, temperatures from 500 to 575K) obtained from spacecraft radio occultation experiments (at 3.6 to 13.4 cm wavelengths) and earth-based radio astronomical observations (1 to 3 cm wavelength range) are compared to laboratory observations at the latter wavelength range under simulated Venus conditions to infer abundances of microwave-absorbing atmospheric constituents, i.e. H2SO4 in a CO2 atmosphere.

Steffes, P. G.

1985-01-01

75

Changes induced in the thermal properties of Galizian soils by the heating in laboratory conditions  

Microsoft Academic Search

The soil properties can be strongly affected by wildfires, causing direct effects on ecosystem productivity and sustainability.\\u000a These effects depend, among other things, on the soil type and on the temperature reached during the fire. The variations\\u000a of thermal properties of several Galizian soils heated in an oven in laboratory conditions at different temperatures (200–500 °C)\\u000a during 15 min have been examined

P. V. Verdes; J. Salgado

2011-01-01

76

The similarities and diversities of signal pathways leading to consolidation of conditioning and consolidation of extinction of fear memory.  

PubMed

It is generally believed that consolidation of long-term memory requires activation of protein kinases, transcription of genes, and new protein synthesis. However, little is known about the signal cascades involved in the extinction of memory, which occurs when the conditioned stimulus is no longer followed by the unconditioned stimulus. Here, we show for the first time that an intra-amygdala injection of transcription inhibitor actinomycin D at the dose that blocked acquisition failed to affect extinction of a learned response. Conversely, protein synthesis inhibitor anisomycin blocked both acquisition and extinction. Extinction training-induced expression of calcineurin was blocked by anisomycin but not by actinomycin D. NMDA receptor antagonist, phosphatidylinositol 3-kinase (PI-3 kinase), and MAP kinase inhibitors that blocked the acquisition also blocked the extinction of conditioned fear. Likewise, PI-3 kinase inhibitor blocked fear training-induced cAMP response element-binding protein (CREB) phosphorylation as well as extinction training-induced decrease in CREB phosphorylation, the latter of which was associated with calcineurin expression and could be reversed by a specific calcineurin inhibitor. Thus, molecular processes that underlie long-term behavioral changes after acquisition and extinction share some common mechanisms and also display different characteristics. PMID:12967993

Lin, Chih-Hung; Yeh, Shiu-Hwa; Lu, Hsin-Yi; Gean, Po-Wu

2003-09-10

77

Laboratory simulations of acid-sulfate weathering under volcanic hydrothermal conditions: Implications for early Mars  

NASA Astrophysics Data System (ADS)

have completed laboratory experiments and thermochemical equilibrium models to investigate secondary mineral formation under conditions akin to volcanic, hydrothermal acid-sulfate weathering systems. Our research used the basaltic mineralogy at Cerro Negro Volcano, Nicaragua, characterized by plagioclase, pyroxene, olivine, and volcanic glass. These individual minerals and whole-rock field samples were reacted in the laboratory with 1 molal sulfuric acid at varying temperatures (65, 150, and 200°C), fluid:rock weight ratios (1:1, 4:1, and 10:1), and durations (1-60 days). Thermochemical equilibrium models were developed using Geochemist's Workbench. To understand the reaction products and fluids, we employed scanning electron microscopy/energy dispersive spectroscopy, X-ray diffraction, and inductively coupled plasma-atomic emission spectroscopy. The results of our experiments and models yielded major alteration minerals that include anhydrite, natroalunite, minor iron oxide, and amorphous Al-Si gel. We found that variations in experimental parameters did not drastically change the suite of minerals produced; instead, abundance, size, and crystallographic shape changed. Our results also suggest that it is essential to separate phases formed during experiments from those formed during fluid evaporation to fully understand the reaction processes. Our laboratory reacted and model predicted products are consistent with the mineralogy observed at places on Mars. However, our results indicate that determination of the formation conditions requires microscopic imagery and regional context, as well as a thorough understanding of contributions from both experiment precipitation and fluid evaporation minerals.

Marcucci, Emma C.; Hynek, Brian M.

2014-03-01

78

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

In the first half of this grant year, laboratory measurements were conducted on the millimeter-wave properties of atmospheric gases under simulated conditions for the outer planet. Significant improvements in the current system have made it possible to accurately characterize the opacity from gaseous NH3 at longer millimeter wavelengths (7 to 10 mm) under simulated Jovian conditions. In the second half of the grant year, it is hoped to extend such measurements to even shorter millimeter-wavelengths. Further analysis and application of the laboratory results to microwave and millimeter-wave absorption data for the outer planets, such as results from Voyager Radio Occultation experiments and earth-based radio astronomical observations will be continued. The analysis of available multispectral microwave opacity data from Venus, including data from the most recent radio astronomical ovservations in the 1.3 to 3.6 cm wavelength range and newly obtained Pioneer-Venus Radio Occulatation measurements at 13 cm, using the laboratory measurements as an interpretative tool will be pursued.

Steffes, Paul G.

1988-01-01

79

Life cycle and behavior of Amblyomma rotundatum (Acari: Ixodidae) under laboratory conditions and remarks on parasitism of toads in Brazil.  

PubMed

The life cycle and behavior of Amblyomma rotundatum were evaluated under laboratory conditions. The experiment started with four engorged females collected from toads (Rhinella schneideri) naturally infested at the Pirapitinga Ecological Station in the state of Minas Gerais, Brazil. Developmental periods of free-living stages were assessed in an incubator at 27 ± 1 °C, >80 % RH and darkness. The complete life cycle, including pre-attachment periods for each parasitic stage, ranged from 126 to 228 days. The pre-attachment, feeding and molting periods increased as the life cycle progressed from larva to adult female. Oviposition lasted about 20 days, with the peak occurring on days 4 and 5. Longevity of nymphs and adult females was quite similar (approximately 250 and 240 days, respectively) and slightly longer than that of larvae. Lesions caused by tick feeding are discussed and a list of known hosts, including new host records for A. rotundatum, is offered. PMID:23100108

Luz, Hermes Ribeiro; Faccini, João Luiz Horacio; Pires, Marcus Sandes; da Silva, Hélio Ricardo; Barros-Battesti, Darci Moraes

2013-05-01

80

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

The recognition of the need to make laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressure which correspond to the altitudes probed by radio occultation experiments, and over a range of frequencies which correspond to both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. Construction was completed of the outer planets simulator and measurements were conducted of the microwave absorption and refraction from nitrogen under simulated Titan conditions. The results of these and previous laboratory measurements were applied to a wide range of microwave opacity measurements, in order to derive constituent densities and distributions in planetary atmospheres such as Venus.

Steffes, P. G.

1986-01-01

81

Structure of high-molecular carbonaceous compound in carbonaceous chondrites and formation of IR-spectroscopically similar compounds in the laboratory.  

PubMed

Main components of carbonaceous matter in carbonaceous chondrites are high molecular organic matter. Examinations of the compounds using pyrolysis GC/MS and FT-IR indicated the structural resemblance of major part of the molecule for all of the compounds from different types of carbonaceous chondrites (8 Antarctic and 2 none-Antarctic meteorites). A carbonaceous matter derived from graphite on a shock experiment using a rail gun (1g projectile at 7 km/s) showed similar IR spectrum to those of the meteoritic high-molecular organic matter. C-60 fullerene also gave a similar compound (with minor differences in IR spectra) on a shock experiment under the same conditions. A shock experiment using coronene also examined. PMID:11541332

Murae, T

1997-01-01

82

Structure of high-molecular carbonaceous compound in carbonaceous chondrites and formation of IR-spectroscopically similar compounds in the laboratory  

NASA Astrophysics Data System (ADS)

Main components of carbonaceous matter in carbonaceous chondrites are high molecular organic matter. Examinations of the compounds using pyrolysis GC/MS and FT-IR indicated the structural resemblance of major part of the molecule for all of the compounds from different types of carbonaceous chondrites (8 Antarctic and 2 none-Antarctic meteorites). A carbonaceous matter derived from graphite on a shock experiment using a rail gun (1g projectile at 7 km/s) showed similar IR spectrum to those of the meteoritic high-molecular organic matter. C-60 fulleren also gave a similar compound (with minor differences in IR spectra) on a shock experiment under the same conditions. A shock experiment using coronene also examined.

Murae, T.

1997-05-01

83

Exchange of nitrogen dioxide (NO2) between plants and the atmosphere under laboratory and field conditions  

NASA Astrophysics Data System (ADS)

Nitric oxide (NO), nitrogen dioxide (NO2), often denoted as nitrogen oxides (NOx), and ozone (O3) are considered as most important compounds in atmospheric chemistry. In remote areas NOx concentration is related to biological activities of soils and vegetation. The emitted NOx will not entirely be subject of long range transport through the atmosphere. Aside oxidation of NO2 by the OH radical (forming HNO3), a considerable part of it is removed from the atmosphere through the uptake of NO2 by plants. The exchange depends on stomatal activity and on NO2 concentrations in ambient air. It is known that NO2 uptake by plants represents a large NO2 sink, but the magnitude and the NO2 compensation point concentration are still under discussion. Our dynamic chamber system allows exchange measurements of NO2 under field conditions (uncontrolled) as well as studies under controlled laboratory conditions including fumigation experiments. For NO2 detection we used a highly NO2 specific blue light converter (photolytic converter) with subsequent chemiluminescence analysis of the generated NO. Furthermore, as the exchange of NO2 is a complex interaction of transport, chemistry and plant physiology, in our field experiments we determined fluxes of NO, NO2, O3, CO2 and H2O. For a better knowledge of compensation point values for the bi-directional NO2 exchange we investigated a primary representative of conifers, Picea abies, under field and laboratory conditions, and re-analyzed older field data of the deciduous tree Quercus robur.

Breuninger, C.; Meixner, F. X.; Thielmann, A.; Kuhn, U.; Dindorf, T.; Kesselmeier, J.

2012-04-01

84

Laboratory modeling of air-sea interaction under severe wind conditions  

NASA Astrophysics Data System (ADS)

Wind-wave interaction at extreme wind speed is of special interest now in connection with the problem of explanation of the sea surface drag saturation at the wind speed exceeding 30 m/s. The idea on saturation (and even reduction) of the coefficient of aerodynamic resistance of the sea surface at hurricane wind speed was first suggested by Emanuel (1995) on the basis of theoretical analysis of sensitivity of maximum wind speed in a hurricane to the ratio of the enthalpy and momentum exchange coefficients. Both field (Powell, Vickery, Reinhold, 2003, French et al, 2007, Black, et al, 2007) and laboratory (Donelan et al, 2004) experiments confirmed that at hurricane wind speed the sea surface drag coefficient is significantly reduced in comparison with the parameterization obtained at moderate to strong wind conditions. Two groups of possible theoretical mechanisms for explanation of the effect of the sea surface drag reduction can be specified. In the first group of models developed by Kudryavtsev & Makin (2007) and Kukulka,Hara Belcher (2007), the sea surface drag reduction is explained by peculiarities of the air flow over breaking waves. Another approach more appropriate for the conditions of developed sea exploits the effect of sea drops and sprays on the wind-wave momentum exchange (Andreas, 2004; Makin, 2005; Kudryavtsev, 2006). The main objective of this work is investigation of factors determining momentum exchange under high wind speeds basing on the laboratory experiment in a well controlled environment. The experiments were carried out in the Thermo-Stratified WInd-WAve Tank (TSWIWAT) of the Institute of Applied Physics. The parameters of the facility are as follows: airflow 0 - 25 m/s (equivalent 10-m neutral wind speed U10 up to 60 m/s), dimensions 10m x 0.4m x 0.7 m, temperature stratification of the water layer. Simultaneous measurements of the airflow velocity profiles and wind waves were carried out in the wide range of wind velocities. Airflow velocity profile was measured by WindSonic ultrasonic wind sensor. The water elevation was measured by the three-channel wave-gauge. Top and side views of the water surface were fixed by CCD-camera. Wind friction velocity and surface drag coefficients were retrieved from the measurements by the profile method. Obtained values are in good agreement with the data of measurements by Donelan et al (2004). The directional frequency-wave-number spectra of surface waves were retrieved by the wavelet directional method (Donelan et al, 1996). The obtained dependencies of parameters of the wind waves indicate existing of two regimes of the waves with the critical wind speed Ucr about 30 m/s. For U10Ucr the dependencies of peak wave period, peak wavelength, significant wave height on the wind speed tend to saturation, in the same time the peak wave slope has the maximum at approximately Ucr and then decreases with the tendency to saturation. The surface drag also tends to saturation for U10>Ucr similarly to (Donelan et al, 2004). Video filming indicates onset of wave breaking with white-capping and spray generation at wind speeds approximately equal to Ucr. We compared the obtained experimental dependencies with the predictions of the quasi-linear model of the turbulent boundary layer over the waved water surface (Reutov&Troitskaya, 1995). Comparing shows that theoretical predictions give low estimates for the measured drag coefficient and wave fields. Taking into account momentum flux associated with the spray generation yields theoretical estimations in good agreement with the experimental data. Basing on the experimental data a possible physical mechanism of the drag is suggested. Tearing of the wave crests at severe wind conditions leads to the effective smoothing (decreasing wave slopes) of the water surface, which in turn reduces the aerodynamic roughnes

Troitskaya, Yuliya; Vasiliy, Kazakov; Nicolay, Bogatov; Olga, Ermakova; Mikhail, Salin; Daniil, Sergeev; Maxim, Vdovin

2010-05-01

85

Consistent null-energy-condition violation: Towards creating a universe in the laboratory  

NASA Astrophysics Data System (ADS)

The null energy condition (NEC) can be violated in a consistent way in models with unconventional kinetic terms, notably, in Galileon theories and their generalizations. We make use of one of these, the scale-invariant kinetic braiding model, to discuss whether a universe can in principle be created by manmade processes. We find that, even though the simplest models of this sort can have both healthy Minkowski vacuum and a consistent NEC-violating phase, there is an obstruction for creating a universe in a straightforward fashion. To get around this obstruction, we design a more complicated model and present a scenario for the creation of a universe in the laboratory.

Rubakov, V. A.

2013-08-01

86

First results from a laboratory facility for measurement of emission spectra under simulated planetary conditions  

NASA Technical Reports Server (NTRS)

We have developed a laboratory spectroscopic facility for the measurement of emission spectra under simulated planetary conditions. Spectral measurements are made from 6 to 13 microns with a scanning grating monochromator equipped with a HgCdTl detector. An environment chamber in service in Hawaii for several years in which we can control the temperature from 77 K to 500 K, the pressure from 10(exp -5) torr to two atmospheres, has been equipped with a 77 K or 273 K cold shield. The shield serves to minimize light reflected off the sample and to aid in development of thermal gradients for obtaining spectra under conditions simulating the thermal environment of airless bodies. Samples are placed in small cups on a temperature controlled substrate allowing measurements of emission due to heating from below by the substrate, or from illumination from a solar simulation source.

Lucey, Paul G.; Domergue-Schmidt, Natalie; Henderson, Bradley G.; Jakosky, Bruce

1993-01-01

87

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

After long arduous work with the simulator, measurements of the refractivity and absorptivity of nitrogen under conditions similar to those for Titan were completed. The most significant measurements, however, were those of the microwave absorption from gaseous ammonia under simulated conditions for the Jovian atmospheres over wavelengths from 1.3 to 22 cm. The results of these measurements are critical in that they confirm the theoretical calculation of the ammonia opacity using the Ben-Reuven lineshape. The application of both these results, and results obtained previously, to planetary observations at microwave frequencies were especially rewarding. Applications of the results for ammonia to radio astronomical observations of Jupiter in the 1.3 to 20 cm wavelength range and the application of results for gaseous H2SO4 under simulated Venus conditions are discussed.

Steffes, P. G.

1986-01-01

88

Laboratory measurements of microwave absorption from gaseous atmospheric constituents under conditions for the outer planets  

NASA Technical Reports Server (NTRS)

Quite often the interpretive work on the microwave and millimeter-wave absorption profiles, which are inferred from radio occultation measurements or radio astronomical observations of the outer planets, employs theoretically-derived absorption coefficients to account for contributions to the observed opacity from gaseous constituents. Variations of the actual absorption coefficients from those which are theoretically derived, especially under the environmental conditions characteristic of the outer planets, can result in significant errors in the inferred abundances of the absorbing constituents. The recognition of the need to make laboratory measurements of the absorptivity of gases such as NH3, CH4, and H2O in a predominantly H2 atmosphere, under temperature and pressure conditions simulating the outer planets' atmospheres, and at wavelengths corresponding to both radio occultation and radio astronomical observations, has led to the development of a facility capable of making such measurements at Georgia Tech. The laboratory measurement system, the measurement techniques, and the proposed experimental regimen for Winter 1985 are described.

Steffes, Paul G.

1986-01-01

89

Rupture speed dependence on loading conditions: Insights from glacier and laboratory stick-slip  

NASA Astrophysics Data System (ADS)

Most earthquakes rupture at a rate approaching, and occasionally surpassing, the shear wave speed, Cs, of the rocks through which they propagate. Recent data have, however, revealed that faults also fail with rupture velocities significantly below Cs. The processes controlling such slow rupture are poorly understood. Surprisingly, glacial slip events generate a variety of rupture velocities at a single location, therefore velocity is not simply controlled by the local material properties. Laboratory experiments suggest that rupture velocities may be controlled by the stresses imposed along a frictional interface prior to the rupture. Moreover, the onset of slip is not governed by a characteristic stress condition (e.g. a static friction coefficient). We compare data from a large Antarctic ice stream, Whillans Ice Plain (WIP), to analogous laboratory measurements. The WIP undergoes bi-daily stick-slip seismic events that displace an ice mass over 100km long. We demonstrate that in both systems, average rupture velocities increase systematically with the pre-rupture stresses, with local rupture velocities exhibiting large variability that correlates well with local interfacial stresses. This analogous behavior indicates that local pre-stress may control rupture behavior in frictional failure events like earthquakes and suggests that fault failure conditions are not controlled by a well-defined threshold value of applied stress.

Fineberg, J.; Walter, J. I.; Svetlizky, I.; Tulaczyk, S. M.; Brodsky, E. E.; Carter, S. P.

2013-12-01

90

Laboratory Evaluation and Application of Microwave Absorption Properties under Simulated Conditions for Planetary Atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments, entry probe radio signal absorption measurements, and earth- based or spacecraft-based radio astronomical (emission) observations can be used to infer abundances of microwave absorbing constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically-derived microwave absorption properties for such atmospheric constituents, or the use of laboratory measurements of such properties taken under environmental conditions that are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. For example, new laboratory measurements completed recently by Mohammed and Steffes (2003 and 2004) under this grant (NAG5-12122,5/1/02-4/30/05), have shown that the millimeter-wavelength opacities from both gaseous phosphine (PH3) and gaseous ammonia ("3) under simulated conditions for the outer planets vary significantly from that predicted by theory over a wide range of temperatures and pressures. These results have directly impacted planning and scientific goals for study of Saturn's atmosphere with the Cassini Radio Science Experiment, as discussed below. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both spacecraft entry probe and orbiter (or flyby) radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. It has been the goal of this investigation to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres.

Steffes, Paul G.

2005-01-01

91

Laboratory Evaluation and Application of Microwave Absorption Properties under Simulated Conditions for Planetary Atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments, entry probe radio signal absorption measurements, and earth-based or spacecraft-based radio astronomical (emission) observations can be used to infer abundances of microwave absorbing constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically-derived microwave absorption properties for such atmospheric constituents, or the use of laboratory measurements of such properties taken under environmental conditions that are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. Laboratory measurements have shown that the centimeter-wavelength opacity from gaseous phosphine (PH3) under simulated conditions for the outer planets far exceeds that predicted from theory over a wide range of temperatures and pressures. This fundamentally changed the resulting interpretation of Voyager radio occultation data at Saturn and Neptune. It also directly impacts planning and scientific goals for study of Saturn's atmosphere with the Cassini Radio Science Experiment and the Rossini RADAR instrument. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both spacecraft entry probe and orbiter (or flyby) radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. It has been the goal of this investigation to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft- and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres,

Steffes, Paul G.

2002-01-01

92

Organics on Mars: Laboratory studies of organic material under simulated martian conditions  

NASA Astrophysics Data System (ADS)

The search for organic molecules and traces of life on Mars has been a major topic in planetary science for several decades, and is the future perspective of several missions to Mars. In order to determine where and what those missions should be looking for, laboratory experiments under simulated Mars conditions have been performed. This thesis describes the effects of simulated martian surface conditions on organic material (amino acids) and living organisms (halophilic archaea). Experiments have been performed to study the stability of thin films of glycine and alanine against UV irradiation under different conditions. Thin films of glycine and alanine have a half-life of 22 ± 5 hours and 3 ± 1 hours, respectively, when extrapolated to Mars-like UV flux levels in vacuum. The presence of a 7 mbar CO2 atmosphere does not affect these destruction rates. Cooling the thin films to 210 K (average Mars temperature) lowers the destruction rate by a factor of 7. The intrinsic amino acid composition of two martian soil analogues, JSC Mars-1 and Salten Skov, has been investigated. The results demonstrated that these analogues are inappropriate for a life-science study in their raw state. Besides amino acids, the response of the halophilic archaea Natronorubrum sp. strain HG-1 to Mars-like conditions, such as low pressure, UV radiation and low temperatures, has been studied. From the results we concluded that this strain would not be a good model organism to survive on the surface of Mars.

ten Kate, Inge Loes

2006-01-01

93

Conditions Similar to Alcohol Impairment  

E-print Network

poisoning. #12;11/19/2013 3 � Don't give them stimulating drinks such as tea or coffee. These can cause paramedics to your position. Situations Requiring Emergency Transportation? � Heart attacks & severe chest

Stuart, Steven J.

94

Performance of transient limiters under laboratory, simulated, and rocket-triggered lightning conditions  

NASA Astrophysics Data System (ADS)

A prototype system was designed and tested that implements a lightning protection method referred to as the fortress concept. The fortress, a structure similar to a Faraday cage, protects the critical system by surrounding it with a continuous metallic skin. Each electrical conductor that must enter the fortress is enclosed within a cable, which is, in turn, enclosed in a metallic shield that terminates at the entry point and is electrically bonded to the fortress' outer metallic surface. Within the fortress, each penetrating conductor is protected by a transient limiter. The system was tested by means of full-threat-level simulated lightning and actual lightening triggered by rockets. Several limited components were subsequently tested by using a laboratory-type surge generator to investigate certain anomalous responses. The fortress concept is reviewed, the operation of the limiters is discussed, and their performance are examined. Explanations are offered for the anomalous responses, and several important design considerations and trade-offs are offered.

Hasbrouck, R. T.; Johnson, J. P.; Breitmeier, J.

1989-07-01

95

Acupuncture Improves Sleep Conditions of Minipigs Representing Diurnal Animals through an Anatomically Similar Point to the Acupoint (GV20) Effective for Humans  

PubMed Central

Acupuncture, an alternative medicine, has been widely applied for people with sleep disturbances; therefore, the effects should be evaluated objectively. Micro-minipigs (MMPigs), the smallest miniature pigs for animal experiments, were used. Acupuncture was performed at two different points: Dafengmen is located on the head and is an anatomically similar point to human-Baihui (GV20), an effective acupoint for sleep disturbances in humans; pig-Baihui is on the back. The procedure was performed as follows: shallow, within 5?mm depth for several seconds; deep, 10–20?mm depth for 20?min. The sleep conditions were evaluated by actigraph, and the amount of catecholamine in pooled urine after acupuncture treatment. MMPigs with deep acupuncture at Dafengmen showed significantly efficient values on actigraph and catecholamine analysis as compared with untreated MMPigs. The effective acupoint for sleep conditions in the porcine model is at an anatomically similar point to humans, rather than the point determined by traditional Chinese medicine. PMID:22461840

Takeishi, Ka-ichiro; Horiuchi, Masahisa; Kawaguchi, Hiroaki; Deguchi, Yoshiki; Izumi, Hiroyuki; Arimura, Emi; Kuchiiwa, Satoshi; Tanimoto, Akihide; Takeuchi, Toru

2012-01-01

96

Monoaromatic hydrocarbon transformation under anaerobic conditions at Seal Beach, California: Laboratory studies  

SciTech Connect

Anaerobic biotransformation of several aromatic hydrocarbons found in gasoline including benzene, toluene, ethylbenzene, m-xylene, p-xylene, and o-xylene (BTEX) was studied in batch anaerobic laboratory microcosms. Aquifer sediment and ground water were obtained from the site of a historic gasoline spill at Seal Beach, California. Sulfate is present in the site ground water at 80 mg/L, and sulfate-reducing activity appears to be the dominant intrinsic BTEX bioremediation process where nitrate is absent. In the laboratory, the microcosms were set up with different electron acceptors (sulfate and nitrate) in site ground water and various defined anaerobic media to estimate intrinsic biodegradation rates and to suggest conditions under which anaerobic bioremediation could be enhanced. In unamended microcosms, anaerobic biotransformation of toluene and m + p-xylene occurred at a rate of 7.2 and 4.1 {micro}g/liter hr, respectively, with sulfate as the apparent electron acceptor. Addition of nitrate stimulated nitrate-reducing conditions and increased rates of toluene and m + p-xylene biotransformation to 30.1 and 5.4 {micro}g/liter hr, respectively. The catabolic substrate range was altered to include ethylbenzene in the nitrate-amended microcosms, suggesting an apparent preferential use of different BTEX compounds depending on the electron acceptor available. Under all the conditions studied, more than twice the amount of nitrate or sulfate was used than could be accounted for by the observed BTEX degradation. The results of these experiments indicate that indigenous microorganisms from the Seal Beach aquifer have significant capability to degrade BTEX hydrocarbons and that intrinsic processes in the Seal Beach aquifer may remediate a portion of the hydrocarbon contamination in situ without intervention. However, the data also suggest that intervention by nitrate addition would enhance the rate and extent of anaerobic BTEX biotransformation.

Ball, H.A.; Reinhard, M. [Stanford Univ., CA (United States). Western Region Hazardous Substance Research Center

1996-02-01

97

42 CFR 493.1467 - Condition: Laboratories performing high complexity testing; cytology general supervisor.  

Code of Federal Regulations, 2012 CFR

...Laboratories performing high complexity testing; cytology general supervisor. 493.1467 Section...Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general...

2012-10-01

98

42 CFR 493.1467 - Condition: Laboratories performing high complexity testing; cytology general supervisor.  

Code of Federal Regulations, 2013 CFR

...Laboratories performing high complexity testing; cytology general supervisor. 493.1467 Section...Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general...

2013-10-01

99

42 CFR 493.1467 - Condition: Laboratories performing high complexity testing; cytology general supervisor.  

Code of Federal Regulations, 2010 CFR

...Laboratories performing high complexity testing; cytology general supervisor. 493.1467 Section...Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general...

2010-10-01

100

42 CFR 493.1467 - Condition: Laboratories performing high complexity testing; cytology general supervisor.  

Code of Federal Regulations, 2011 CFR

...Laboratories performing high complexity testing; cytology general supervisor. 493.1467 Section...Laboratories performing high complexity testing; cytology general supervisor. For the subspecialty of cytology, the laboratory must have a general...

2011-10-01

101

A Laboratory Exercise to Illustrate Increased Salivary Cortisol in Response to Three Stressful Conditions Using Competitive ELISA  

NSDL National Science Digital Library

Here, we outline a laboratory exercise that uses a competitive ELISA kit to illustrate the response of salivary cortisol concentrations to three stressful conditions: presentation stress, fasting stress, and competition stress

Mark F. Haussmann (Iowa State University Department of Ecology, Evolution, and Organismal Biology); Carol M. Vleck (Iowa State University Department of Ecology, Evolution, and Organismal Biology); Eugenia S. Farrar (Iowa State University Department of Ecology, Evolution, and Organismal Biology)

2007-03-01

102

Laboratory degradation rates of 11 pyrethroids under aerobic and anaerobic conditions.  

PubMed

Degradation of 11 pyrethroids was measured over approximately 100 days in three sediment/water systems under aerobic and anaerobic conditions at 25 °C in the dark. The three California sediments represented a range of textures and organic matter. Test compounds were bifenthrin, cypermethrin, ?-cypermethrin, cyfluthrin, ?-cyfluthrin, deltamethrin, esfenvalerate, fenpropathrin, ?-cyhalothrin, ?-cyhalothrin, and permethrin. A non-standard design was employed to keep conditions essentially the same for all compounds. The test compounds were applied as two test mixtures (six active ingredients per mixture, with bifenthrin common to both) at approximately 50 ?g of test compound/kg of sediment (dry weight). Extracts of sediment/water were cleaned up by solid-phase extraction, concentrated, and analyzed by gas chromatography/mass spectrometry (except deltamethrin) against matrix-matched standards, with cyfluthrin-d6 as an internal standard. Deltamethrin was analyzed by liquid chromatography/tandem mass spectrometry using deltamethrin-phenoxy-(13)C6 as an internal standard. Similar degradation rates of bifenthrin and for related isomeric compounds (e.g., cyfluthrin and ?-cyfluthrin) were generally measured in both mixtures for each sediment. First-order half-lives under aerobic conditions ranged from 2.9 to greater than 200 days, with a median value of 18 days. Under anaerobic conditions, the range was from 20 to greater than 200 days, with a median value of 70 days. PMID:23641910

Meyer, Brian N; Lam, Chung; Moore, Sean; Jones, Russell L

2013-05-22

103

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. The use of theoretically derived microwave absorption properties for such atmospheric constituents, or using laboratory measurements of such properties under environmental conditions which are significantly different than those of the planetary atmosphere being studied, often leads to significant misinterpretation of available opacity data. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. The goal of this investigation was to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres.

Steffes, Paul G.

1992-01-01

104

Measured and calculated evaporation losses of two petroleum hydrocarbon herbicide mixtures under laboratory and field conditions  

SciTech Connect

Evaporation rates of two weed oils were measured under laboratory and field conditions. Rates were also calculated by assuming first-order evaporation of the oil components (represented by hydrocarbon references). Beacon selective and Chevron nonselective weed oils exhibited evaporation rates 1.4-1.9 and 0.9 times the calculated rates, respectively, for 8-10 mg/cm/sup 2/ on inert surfaces in the laboratory. The relative rates were increased to 3-15 (Beacon) and 1.6 (Chevron) under a slight breeze (0.43 m/s) with turbulence. The half-life of Beacon oil applied at 6-7 mg/cm/sup 2/ to moist soil in an unplanted field was 51 min (10-20/sup 0/C), while the calculated half-life was 57 min. In an alfalfa field, 90% of the Chevron oil from a deposit of 0.15-0.22 mg/cm/sup 2/ (20-40/sup 0/C) evaporated in 26-45 and 53-127 min from glass plates and paper filters, respectively; average calculated time was 40 min. Evaporation rates from alfalfa foliage and glass plates compared well. 15 references, 6 figures, 8 tables.

Woodrow, J.E.; Seiber, J.N.; Kim, Y.

1986-08-01

105

Laboratory and theoretical modeling of air-sea momentum transfer under severe wind conditions  

NASA Astrophysics Data System (ADS)

The laboratory experiments on investigation of aerodynamic resistance of the waved water surface under severe wind conditions (up to U10 ? 40 m s-1) were carried out, complemented by measurements of the wind-wave spectra. The tendency to saturation of the surface drag was observed for wind speeds exceeding 25 m s-1, accompanied by the saturation of wind-wave slopes. The effect of surface drag saturation can be explained quantitatively within the quasi-linear model of the air boundary layer above the waved water surface, when the contribution of the short-wave part of the wind-wave spectrum to aerodynamic resistance of the water surface is taken into account.

Troitskaya, Y. I.; Sergeev, D. A.; Kandaurov, A. A.; Baidakov, G. A.; Vdovin, M. A.; Kazakov, V. I.

2012-11-01

106

Influence of Packaging and Processing Conditions on the Decontamination of Laboratory Biomedical Waste by Steam Sterilization  

PubMed Central

The conditions for optimal steam decontamination of polypropylene bags half loaded with laboratory biomedical waste were studied (276 bags were processed). Controls were single-closed bags without water added or incisions made in the top, standing freely in an autoclave set at 121°C. The average time required to reach 121°C at the load center was 46 min for controls. A significant increase in this time occurred following addition of water to bags without incisions (60 min), with double bagging (60 min), or when using vertical containers (82 min). A significant decrease occurred when bags were slashed (37 min) or processed at 123°C (32 min) or 132°C (19 min). Horizontal containers or addition of water to slashed bags had no significant effect. PMID:16349131

Ozanne, Gérard; Huot, Roger; Montpetit, Claude

1993-01-01

107

Interpreting EChO's future data: biological laboratory extimates under M star's planetary surface conditions  

NASA Astrophysics Data System (ADS)

The EChO Exoplanet Atmosphere Characterization mission will have in the midst of its main targets, planets that orbit M stars in their or very close to their habitable zone. In this framework at the Astronomical Observatory of Padova (INAF) we are going to perform experiments that will give us an idea about the possible modification of the atmosphere by photosynthetic biota present on the planet surface. In the framework of the project "Atmosphere In a Test Tube", planetary environmental conditions are being performed. The bacteria that are being studied are Acaryochloris marina, Chroococcidiopsis sp., Cyanidium Caldarium and Halomicronema hongdechloris and tests are being performed with LISA ambient simulator in the laboratory of the Padova Astronomical Observatory.

Erculiani, Marco S.; Claudi, Riccardo U.; Giro, Enrico; Galletta, Giuseppe; D'Alessandro, Maurizio; Farisato, Giancarlo; Lessio, Luigi; Micela, Giuseppina; Billi, Daniela

2014-08-01

108

Numerical simulations of thermal convection in rotating spherical shells under laboratory conditions  

NASA Astrophysics Data System (ADS)

An exhaustive study, based on numerical three-dimensional simulations, of the Boussinesq thermal convection of a fluid confined in a rotating spherical shell is presented. A moderately low Prandtl number fluid (?=0.1) bounded by differentially-heated solid spherical shells is mainly considered. Asymptotic power laws for the mean physical properties of the flows are obtained in the limit of low Rossby number and compared with laboratory experiments and with previous numerical results computed by taking either stress-free boundary conditions or quasi-geostrophic restrictions, and with geodynamo models. Finally, using parameters as close as possible to those of the Earth's outer core, some estimations of the characteristic time and length scales of convection are given.

Garcia, Ferran; Sánchez, Juan; Net, Marta

2014-05-01

109

Noise Characterization in Free Space Polarization Modulation Communication Using Simulated Atmospheric Conditions in Laboratory  

E-print Network

We present a practical scheme for measurement-device-independent polarization shift keying using two state polarization encoding. Most of the previous work on optical free space laser communications through the atmosphere was concentrated on intensity modulated systems. However, polarization modulated systems may be more appropriate for such communication links, because the polarization seems to be the most stable characteristic of a laser beam while propagating through the atmosphere. Thus, a detailed comparison between intensity and polarization modulated systems is of much interest. We analyse the noise in presence of simulated smoke and fog conditions within laboratory and propose a practical scheme for extracting message from the received data. The proposed method uses only two detectors to analyse the polarizations and the practical de?nition of state of polarization enables a higher signal-to-noise ratio even in presence of depolaration elements in atmosphere such as fog and smoke. The system also take...

Soorat, Ram

2014-01-01

110

Laboratory experiment on poroelastic behavior of Berea sandstone under two-phase fluid flow condition  

NASA Astrophysics Data System (ADS)

Coupled two-phase fluid flow and deformation of Berea sandstone was discussed through laboratory experiments and numerical simulation. In the experiment, a triaxial compression apparatus with flow pipes to pass fluids through a rock sample was used. The experimental procedures were as follows. Firstly, external stresses close to hydrostatic condition were applied to a water saturated cylindrical Berea sandstone sample. Then, compressed air was infiltrated from the bottom of the sample. During the experiment, both axial and circumferential strains at half the height of the sample and volumetric discharge of water at the outlet were measured. Both strains showed sudden extensions after a few seconds, and monotonically extended thereafter. The volumetric discharge of water showed that air breakthrough occurred in around 100 seconds after the commencement of the air injection. Numerical simulations based on thermodynamically consistent constitutive equations were conducted in order to quantitatively analyze the experimental results. In a simulation in which the material was assumed to be homogeneous isotropic, the axial strain at half the height of the sample and the volumetric discharge of water at the outlet were reproduced well by using reasonable parameters, while that was not the case with the circumferential strain at half the height of the sample. On the other hand, in a simulation in which anisotropy of the material was introduced, all experimental data were reproduced well by using reasonable parameters. This result is reasonable because Berea sandstone is well known to be anisotropic under such Terzaghi effective stress condition as used in our experiment, i.e., 3.0 MPa (Hart and Wang, 1999; Hart, 2000). Our results indicate that the theory of poroelasticity for two-phase fluid system can explain the strain behavior of porous media for two-phase fluid flow observed in laboratory experiments.

Goto, H.; Aichi, M.; Tokunaga, T.; Yamamoto, H.; Ogawa, T.; Aoki, T.

2013-12-01

111

Measuring ignitability for in situ burning of oil spills weathered under Arctic conditions: from laboratory studies to large-scale field experiments.  

PubMed

This paper compares the ignitability of Troll B crude oil weathered under simulated Arctic conditions (0%, 50% and 90% ice cover). The experiments were performed in different scales at SINTEF's laboratories in Trondheim, field research station on Svalbard and in broken ice (70-90% ice cover) in the Barents Sea. Samples from the weathering experiments were tested for ignitability using the same laboratory burning cell. The measured ignitability from the experiments in these different scales showed a good agreement for samples with similar weathering. The ice conditions clearly affected the weathering process, and 70% ice or more reduces the weathering and allows a longer time window for in situ burning. The results from the Barents Sea revealed that weathering and ignitability can vary within an oil slick. This field use of the burning cell demonstrated that it can be used as an operational tool to monitor the ignitability of oil spills. PMID:21714974

Fritt-Rasmussen, Janne; Brandvik, Per Johan

2011-08-01

112

Performance of transient limiters under laboratory, simulated, and rocket-triggered lightning conditions  

SciTech Connect

We have designed and tested a prototype system that implements a lightning-protection method referred to as the ''fortress concept.'' The fortress, a structure similar to a Faraday cage, protects the critical system by surrounding it with a continuous metallic skin. Each electrical conductor that must enter the fortress is enclosed within a cable, which is, in turn, enclosed in a metallic shield that terminates at the entry point and is electrically bonded to the fortress' outer metallic surface. Within the fortress, each penetrating conductor is protected by a transient limiter. The system was tested by means of full-threat-level simulated lightning and actual lightening triggered by rockets. Several limited components were subsequently tested by using a laboratory-type surge generator to investigate certain anomalous responses. This paper reviews the fortress concept, discusses the operation of the limiters, and examines their performance. Explanations are offered for the anomalous responses, and several important design considerations and trade-offs are offered. 3 refs., 15 figs.

Hasbrouck, R.T.; Johnson, J.P.; Breitmeier, J.

1989-07-02

113

The formation of sulfate and elemental sulfur aerosols under varying laboratory conditions: implications for early earth.  

PubMed

The presence of sulfur mass-independent fractionation (S-MIF) in sediments more than 2.45?×?10(9) years old is thought to be evidence for an early anoxic atmosphere. Photolysis of sulfur dioxide (SO(2)) by UV light with ??laboratory studies to create a S-MIF; however, sulfur must leave the atmosphere in at least two chemically different forms to preserve any S-MIF signature. Two commonly cited examples of chemically different sulfur species that could have exited the atmosphere are elemental sulfur (S(8)) and sulfuric acid (H(2)SO(4)) aerosols. Here, we use real-time aerosol mass spectrometry to directly detect the sulfur-containing aerosols formed when SO(2) either photolyzes at wavelengths from 115 to 400?nm, to simulate the UV solar spectrum, or interacts with high-energy electrons, to simulate lightning. We found that sulfur-containing aerosols form under all laboratory conditions. Further, the addition of a reducing gas, in our experiments hydrogen (H(2)) or methane (CH(4)), increased the formation of S(8). With UV photolysis, formation of S(8) aerosols is highly dependent on the initial SO(2) pressure; and S(8) is only formed at a 2% SO(2) mixing ratio and greater in the absence of a reductant, and at a 0.2% SO(2) mixing ratio and greater in the presence of 1000?ppmv CH(4). We also found that organosulfur compounds are formed from the photolysis of CH(4) and moderate amounts of SO(2). The implications for sulfur aerosols on early Earth are discussed. Key Words: S-MIF-Archean atmosphere-Early Earth-Sulfur aerosols. PMID:21087157

DeWitt, H Langley; Hasenkopf, Christa A; Trainer, Melissa G; Farmer, Delphine K; Jimenez, Jose L; McKay, Christopher P; Toon, Owen B; Tolbert, Margaret A

2010-10-01

114

Hydrological conditions at the 317/319 Area at Argonne National Laboratory  

SciTech Connect

This study examined the hydrological conditions of the glacial till underlying the 317/319 Area at Argonne National Laboratory (ANL) near Lemont, Illinois. The study's purpose was to review and summarize hydrological data collected by ANL's Environment, Safety, and Health Department and to characterize, based on these data, the groundwater movement and migration of potential contaminants in the area. Recommendations for further study have been made based on the findings of this review. The 317/319 Area is located between Meridian Road and the southern border of ANL. The 317 Area was commissioned in the late 1940s for the temporary storage of radioactive waste. Low- and high-level solid radioactive waste is stored in partially buried concrete vaults. Low-level radioactive waste awaiting shipment for off-site disposal is stored in aboveground steel bins north of the vaults. The 319 Area is an inactive landfill, located east of the 317 Area that was used for the disposal of general refuse, demolition debris, and laboratory equipment. Fluorescent light bulbs, chemical containers, and suspect waste were also placed in the landfill. Liquid chemical wastes were disposed of at each site in gravel-filled trenches called French drains.'' The 317/319 Area is underlain by a silty clay glacial till. Dolomite bedrock underlies the till at an average depth of about 19.5m. Organic contaminants and radionuclides have been detected in groundwater samples from wells completed in the till. Fractures in the clay as well as sand and gravel lenses present in the till could permit these contaminants to migrate downward to the dolomite aquifer. At the time of this report, no chemical quality analyses had been made on groundwater samples from the dolomite. The study found that existing information about subsurface characteristics at the site is inadequate to identify potential pathways for contaminant migration. 14 refs., 13 figs., 6 tabs.

Patton, T.L.; Pearl, R.H.; Tsai, S.Y.

1990-08-01

115

Germination of Ocotea pulchella (Nees) Mez (Lauraceae) seeds in laboratory and natural restinga environment conditions.  

PubMed

The germination response of Ocotea pulchella (Nees) Mez seeds to light, temperature, water level and pulp presence is introduced. The laboratory assays were carried out in germination chambers and thermal-gradient apparatus, whereas the field assays were performed in environments with distinct light, temperature and soil moisture conditions within a permanent parcel of Restinga forest of the Parque Estadual da Ilha do Cardoso, Cananéia, São Paulo. The seeds do not exhibit dormancy, they are non photoblastic, and a loss of viability in dry stored seeds can be related to a decrease in water content of the seed. The presence of the pulp and the flooded substratum influenced negatively the germination of O. pulchella seeds tested in the laboratory. Otherwise, light and temperature probably are not limiting factors of the germination of O. pulchella seeds in the natural environment of Restinga. The optimum temperature range for germination of Ocotea pulchella seeds was 20 to 32 degrees C, the minimum or base temperature estimated was 11 degrees C and the maximum ranged between 33 and 42 degrees C. The isotherms exhibited a sigmoidal pattern well described by the Weibull model in the sub-optimal temperature range. The germinability of O. pulchella seeds in the understorey, both in wet and dry soil, was higher than in gaps. Germination was not affected by fluctuations in soil moisture content in the understorey environment, whereas in gaps, germination was higher in wet soils. Thus, the germination of this species involves the interaction of two or more factors and it cannot be explained by a single factor. PMID:19802455

Pires, L A; Cardoso, V J M; Joly, C A; Rodrigues, R R

2009-08-01

116

Residential Gas-Fired Space-Conditioning Research and Development at Brookhaven National Laboratory  

SciTech Connect

Brookhaven National Laboratory has work on-going involving industrial development of gas- and oil-fired space-heating equipment. An analysis of the energy situation indicates that there are significant opportunities to reduce energy waste. These opportunities involve the elimination or reduction of unnecessary consumption and the development of more-efficient equipment. Various options exist for the development of advanced space-conditioning equipment having improved efficiency. The three basic approaches are (1) to increase the capacity of the heat exchanger, (2) to operate with a reduction in excess air, and (3) to reduce standby and cycling losses. The ideal operation of a conventional boiler or furnace is to allow the heat exchanger to operate in the condensing mode at the temperature where the latent heat of vaporization of water vapor in the flue gas is recovered. The resulting efficiency can reach close to 95%. The gas-fired research and development work presently on-going involve the following: (1) a variable firing rate gas burner, (2) a gas-fired pulse combustion furnace capable of firing 40,000 to 90,000 Btu/hr, (3) a gas-fired pulse combustion boiler with an output of 36,000 Btu/hr, (4) a gas-fired heat pipe furnace firing at 60,000 Btu/hr, and (5) a nonelectric Rankine-cycle gas furnace. A materials program is also underway to identify cost-effective materials for condensing oil- and gas-fired systems, and a study has just been completed that identifies technology for improving the efficiency of heating systems. The method for laboratory and field testing that will assist in commercialization of new, advanced equipment is presented.

Woodworth, L.M.

1980-01-01

117

Demographic fitness of Belminus ferroae (Hemiptera: Triatominae) on three different hosts under laboratory conditions  

PubMed Central

Triatominae are widely recognised for their role as vectors of Trypanosoma cruzi. One of the main biological characteristics of this subfamily is their obligate haematophagous condition. However, previous studies on Belminus herreri and Belminus ferroae suggested that cockroaches are their principal hosts in domiciles. Due to this peculiar behaviour, the aim of this study was to analyse several demographic and reproductive parameters of B. ferroae fed on three different hosts (mice, cockroaches and Rhodnius prolixus) and relate B. ferroae fitness to these alternative hosts. The cohorts were reared under constant conditions. The egg hatching rate was similar for cohorts fed on cockroaches (69.4%) and R. prolixus (63.8%), but was much lower for the cohort fed on mice (16%). The development time from the nymph to adult stage and the average age of first reproduction (?) presented lower values in the cohort fed on cockroaches, which is consistent with the higher population growth rate associated with this host. Demographic parameters [intrinsic rate of natural increase, finite rate of population growth, net reproductive rate and damping ratio] showed statistically significant differences between the cohorts. Analysis of the life history of B. ferroae revealed a higher fitness related to the cockroach. The implications of these results for the origin of the subfamily are discussed. PMID:24141961

Sandoval, Claudia Magaly; Medone, Paula; Nieves, Elsa Evelia; Jaimes, Diego Alexander; Ortiz, Nelcy; Rabinovich, Jorge Eduardo

2013-01-01

118

Salmonella transfer potential during hand harvesting of tomatoes under laboratory conditions.  

PubMed

Tomato good agricultural practices, mandatory guidelines in Florida, do not have specific regulations for glove use during tomato harvesting. The objective of the research reported here was to evaluate Salmonella transfer from contaminated gloves to tomatoes and vice versa upon single and subsequent touches. Experiments were performed using mature, green, round tomatoes with two types of gloves (reusable and single use) and two hygienic conditions of reusable glove (clean and dirty [fouled with tomato leaves]). The transfer scenarios used during experiments were glove to tomato, tomato to glove, and glove to up to 25 subsequently touched tomatoes. The inoculated surface (6 log CFU per surface), after drying for 24 h, touched the uninoculated surface for 5 s. Salmonella populations from gloves and tomatoes were enumerated on nonselective and selective agar supplemented with 80 ?g/ml rifampin. Enrichments were performed when counts fell below the detection limit. The rates of Salmonella transfer to tomatoes during a single touch were similar for single-use and reusable gloves; transfer from tomatoes to gloves was higher to single-use gloves than to reusable gloves under wet (0 h) inoculation conditions. Dirty reusable gloves did not transfer more Salmonella than clean reusable gloves during single contact under any conditions. When a single glove was sequentially touched to multiple tomatoes, clean reusable gloves transferred higher levels of Salmonella to the first few tomatoes touched than did single-use gloves and dirty reusable gloves. As workers' gloves became dirty over time during harvest, the risk of Salmonella transfer to tomatoes did not increase. PMID:23905789

Brar, Pardeepinder Kaur; Danyluk, Michelle D

2013-08-01

119

Validity of actigraphs uniaxial and triaxial accelerometers for assessment of physical activity in adults in laboratory conditions  

PubMed Central

Background Few studies to date have directly compared the Actigraphs GT1M and the GT3X, it would be of tremendous value to know if these accelerometers give similar information about intensities of PA. Knowing if output is similar would have implications for cross-examination of studies. The purpose of the study was to assess the validity of the GT1M and the GT3X Actigraph accelerometers for the assessment of physical activity against oxygen consumption in laboratory conditions. Methods Forty-two college-aged participants aged 18-25 years wore the GT1M and the GT3X on their right hip during treadmill exercise at three different speeds, slow walking 4.8 km.h-1, fast walking 6.4 km.h-1, and running 9.7 km.h-1). Oxygen consumption was measured minute-by minute using a metabolic system. Bland-Altman plots were used to assess agreement between activity counts from the GT3X and GT1M, and correlations were assessed the ability of the accelerometers to assess physical activity. Results Bias for 4.8 km.h-1 was 2814.4 cpm (limits 1211.3 to 4417.4), for 6.4 km.h-1 was 3713.6 cpm (limits 1573.2 to 5854.0), and for 9.7 km.h-1 was?3811.2 cpm (limits 842.1 to 6780.3). Correlations between counts per minute for the GT1M and the GT3X were significantly correlated with VO2 (r?=?0.881, p?

2013-01-01

120

Biodegradation of chlorsulfuron and metsulfuron-methyl by Aspergillus niger in laboratory conditions.  

PubMed

Two sulfonylurea herbicides, chlorsulfuron and metsulfuron-methyl, were studied under laboratory conditions, in order to elucidate the biodegradation pathway operated by Aspergillus niger, a common soil fungus, which is often involved in the degradation of xenobiotics. HPLC-UV was used to study the kinetic of degradation, whereas LC-MS was used to identify the metabolites structure. In order to avoid the chemical degradation induced by a decrease in pH, due to the production of citric acid by the fungus, the experiments were performed in a buffered neutral medium. No significant degradation for both compounds was observed in mineral medium with 0.2% sodium acetate. On the contrary, in a rich medium, after 28 days the degradations, chemical degradation excluded, were about 30% for chlorsulfuron and 33% for metsulfuron-methyl. The main microbial metabolites were obtained via cleavage of the sulfonylurea bridge. In addition the fungus seems to be able to hydroxylate the aromatic ring of chlorsulfuron. In the case of metsulfuron-methyl the only detected metabolite was the triazine derivative, while the aromatic portion was completely degraded. Finally, the demethylation of the methoxy group on the triazine ring, previously observed with a Pseudomonas fluorescens strain, was not observed with A. niger. PMID:14649705

Boschin, Giovanna; D'Agostina, Alessandra; Arnoldi, Anna; Marotta, Ester; Zanardini, Elisabetta; Negri, Marco; Valle, Anna; Sorlini, Claudia

2003-11-01

121

Persistence of cyfluthrin in three Malaysian agricultural soils under laboratory conditions.  

PubMed

The influence of temperature, moisture and organic matter on the persistence of cyfluthrin was determined using three types of Malaysian soils, namely clay, clay loam and sandy clay loam obtained from a tomato farm in Cameron Highlands, Pahang. The persistence of cyfluthrin was observed in the laboratory at two temperature levels of 25 and 35 degreeC and field water capacity of 30 and 80%. Treated soil samples were incubated in a growth chamber for 1, 2, 3, 5, 7, 10, 14, 21 and 28 days. The results from the incubation studies showed that temperature and organic matter content significantly reduced the half-life (t1/2) values of cyfluthrin in the three soil types, but moisture content had very little effect. It was observed that cyfluthrin persisted longer at lower temperature and moisture content and higher organic matter content in all the three soil types. The present study demonstrated that under the tropical conditions of Malaysia, cyfluthrin dissipated rapidly in soils compared to its dissipation in soils of temperate regions, evidently due to high temperature. PMID:24558812

Lee-Yin, Choo; Ismaill, B S; Salmijah, S; Halimah, M

2013-09-01

122

Effects of Mirazid® and myrrh volatile oil on adult Fasciola gigantica under laboratory conditions  

PubMed Central

Objective To evaluate the effects of Mirazid® and myrrh volatile oil on adult Fasciola gigantica (F. gigantica ) under laboratory conditions. Methods The effects of oleoresin extract of myrrh (Mirazid®) and myrrh volatile oil on the surface morphology of adult F. gigantica following treatment in vitro had been determined by scanning electron microscopy. The results were compared with those observed in the fluke tegument following incubation in triclabendazole sulphoxide (TCBZ-SO), active form, (Fasinex®, Ciba-Geigy). Results Observations of the efficacy of Mirazid® oleoresin extract and myrrh volatile oil indicated that both products showed dose-dependent anthelmintic efficacy. The anterior half of the fluke was consistently more severely affected than the posterior half. The surface changes induced by Mirazid® oleoresin extract were less severe than those observed after exposure to either myrrh volatile oil or TCBZ-SO. Flukes showed swelling after these treatments, but its level and blebbing were much greater with myrrh volatile oil; in which patches of tegumental sloughing were observed in the apical cone and the posterior mid-body region of flukes. This was not observed after treatment with Mirazid® oleoresin extract. Conclusions The comparatively more disruption, observed in myrrh volatile oil exposed specimens, compared to that exposed to Mirazid® oleoresin extract might suggest that the anthelmintic activity of Mirazid® oleo resin extract was attributed to its content of volatile oil. So, increasing the concentration of myrrh volatile oil in Mirazid® might possibly help to developing its anthelmintic activity. PMID:23569864

Massoud, AM; Shalaby, HA; El Khateeb, RM; Mahmoud, MS; Kutkat, MA

2012-01-01

123

Acetochlor mineralization and fate of its two major metabolites in two soils under laboratory conditions.  

PubMed

The degradation of the herbicide acetochlor, in a neoluvisol and in a calcosol were studied as a function of depth (0-25cm and 25-50cm) and temperature (25 degrees C and 15 degrees C) under controlled laboratory conditions during 58 and 90 days, respectively. The surface and sub-surface soil samples were respectively spiked with 1 and 0.01mgkg(-1) of 14C-acetochlor, the concentrations observed in previous field monitoring. The half-lives (DT50) varied from 1.4 to 14.9 days depending on the soil, temperature and applied concentration. The maximal mineralization (24%) was observed for the surface calcosol at 25 degrees C. The comparison of results obtained for sterilized and non-sterilized soils, the decrease of DT50 with the increase of temperature, the shape of CO2 emissions and the increase of number of aerobic endogenous microflora through the experiment suggested that biological process are dominant in degradation. A particular attention was paid to the formation and dissipation of metabolites ESA (ethanesulphonic acid) and OA (oxanilic acid) during the whole experiment. At 25 degrees C, ESA and OA were observed after three days, but as ESA concentration decreased over time in surface calcosol, it remained constant in surface neoluvisol. A difference in ESA/OA ratio depends on the soil with a predominance of OA in surface neoluvisol and a disappearance of OA in surface calcosol. PMID:18078980

Dictor, Marie-Christine; Baran, Nicole; Gautier, Anne; Mouvet, Christophe

2008-03-01

124

Laboratory Measurements of the Millimeter-Wavelength Sulfur Dioxide Absorption Spectrum under Simulated Venus Conditions  

NASA Astrophysics Data System (ADS)

Over 130 laboratory measurements of the 2-4 millimeter wavelength opacity of sulfur dioxide in a carbon dioxide atmosphere under simulated conditions for the upper Venus troposphere (temperatures between 308-343 K and pressures between 0.03- 2 bar) have been made. These measurements along with the centimeter wavelength measurements by Steffes et al. (Icarus, 2014, in press) have been used to empirically assess existing formalisms for sulfur dioxide opacity in a carbon dioxide atmosphere (Fahd and Steffes Icarus 97, 1992 and Suleiman et al. JGR 101, E2 1996). The Van Vleck and Weisskopf Model (VVW) used by Fahd and Steffes with the JPL rotational line catalog (Pickett, et al. JQSRT 60, 1998) was found to fit 85.88% of all 500 measurements within the 2-sigma uncertainty. This model was implemented in the new Georgia Tech Venus Radiative Transfer Model (GT-VRTM) which is capable of computing both disk-averaged and localized brightness temperatures of Venus. These are compared to observations. This work will improve retrievals of the atmospheric abundance of sulfur dioxide from observations of the Venus atmosphere. This work was supported by the NASA Planetary Atmospheres Program under Grant NNX11AD66G.

Bellotti, Amadeo; Steffes, Paul G.

2014-11-01

125

Life-cycle and host specificity of Amblyomma tigrinum (Acari: Ixodidae) under laboratory conditions.  

PubMed

Biological data of three generations of Amblyomma tigrinum in the laboratory are reported and the suitability of different host species for immature ticks are compared. Grouping the three generations, infestations by both the larval and nymphal stages were performed on chickens (Gallus gallus), wistar rats (Rattus norvegicus), rabbits (Orytolagus cuniculus), wild mice (Calomys callosus), dogs (Canis familiaris) and opossums (Didelphis albiventris). Only dogs were used for infestations by adult ticks. Tick developmental periods were observed in an incubator at 27 degrees C and RH 90%. The proportion of engorged larvae recovered from chickens (21.7% of the exposed larvae) was significantly larger (p<0.001) than those from the five mammal species used in the infestations (maximum of 3.1%). A significant larger (p<0.01) proportion of engorged larvae successfully molted after being fed on chickens than on mammal hosts. The proportion of engorged nymphs recovered from chickens (28.8% of the exposed nymphs) was significantly larger (p0.001) than those from mammal hosts (range: 0-2.1%). Larvae showed similar feeding periods on exposure to different host species, except for those larvae fed on C. callosus, which showed significantly longer (p<0.001) feeding periods. Engorged larvae detachment peaked on the 5th feeding day, followed by the 6th day, on all hosts except for C. callosus. Larval premolt periods were similar for engorged ticks exposed to different host species, except for larvae fed on dogs, which showed significantly longer (p<0.001) premolt periods. Host detachment of engorged nymphs peaked on the 6th feeding day on chickens. Although nymphal detachment on rats peaked on the 8th day, only 15 nymphs were recovered from this host species. In a sample of 144 F3 nymphs fed on chickens no significant difference (p>0.10) was found between the feeding or premolt periods of 82 males and 62 females, but female nymphs were significantly heavier (p<0.005) than male nymphs. Sixteen engorged females (61.5% of the exposed ticks) were recovered after being fed on dogs. and all these females laid viable eggs. Chickens, the only avian host, were the most suitable host when compared with the five mammal species. Dogs were demonstrated to be a suitable host for adults of A. tigrinum, which is consistent with, several reports of adult A. tigrinum ticks parasitizing dogs in different areas of South America. Our results reinforce that in these same areas avian species are the major hosts for immature stages of this tick species. PMID:12475081

Labruna, Marcelo B; Souza, Silvio L P; Menezes, Ana C; Horta, Maurício C; Pinter, Adriano; Gennari, Solange M

2002-01-01

126

42 CFR 493.1409 - Condition: Laboratories performing moderate complexity testing; technical consultant.  

Code of Federal Regulations, 2010 CFR

...moderate complexity testing; technical consultant. 493.1409 Section 493.1409 ...moderate complexity testing; technical consultant. The laboratory must have a technical consultant who meets the qualification...

2010-10-01

127

42 CFR 493.1415 - Condition: Laboratories performing moderate complexity testing; clinical consultant.  

Code of Federal Regulations, 2010 CFR

...moderate complexity testing; clinical consultant. 493.1415 Section 493.1415 ...moderate complexity testing; clinical consultant. The laboratory must have a clinical consultant who meets the qualification...

2010-10-01

128

Similarities between inherited demyelinating neuropathies and Wallerian degeneration: an old repair program may cause myelin and axon perturbation under nonlesion conditions.  

PubMed

Wallerian degeneration (WD) and inherited demyelinating neuropathies of the Charcot-Marie-Tooth type 1 (CMT1) appear to represent completely distinct events. CMT1-like diseases are chronic disorders of peripheral nerves that are genetically caused and lead to secondary neurodegenerative events, resulting in usually non-treatable disabilities, whereas WD is an acute, usually transient, reaction on injuries, aiming to allow peripheral nerve regeneration. Despite these differences, there are some striking similarities regarding molecular characteristics of neural cells in the affected peripheral nerves. The most conspicuous similarities might comprise the inflammatory component in both situations, as identified in appropriate mouse models. However, although inflammation is a beneficial component in WD, leading to removal of regrowth-repellent myelin debris, inflammation in CMT1 mouse models causes damage of initially intact nerve fibers. We hypothesize that, in CMT1 models, molecular pathways are activated that are shared with an important repair program after peripheral nerve injury, but lead to neural perturbation when activated under nonlesion conditions, as is the case in CMT1. These novel insights into the pathogenesis of CMT1 might be instrumental for the development of new therapeutic options in humans. PMID:23831295

Martini, Rudolf; Klein, Dennis; Groh, Janos

2013-09-01

129

Photosynthetic acclimation responses of maize seedlings grown under artificial laboratory light gradients mimicking natural canopy conditions  

PubMed Central

In this study we assessed the ability of the C4 plant maize to perform long-term photosynthetic acclimation in an artificial light quality system previously used for analyzing short-term and long-term acclimation responses (LTR) in C3 plants. We aimed to test if this light system could be used as a tool for analyzing redox-regulated acclimation processes in maize seedlings. Photosynthetic parameters obtained from maize samples harvested in the field were used as control. The results indicated that field grown maize performed a pronounced LTR with significant differences between the top and the bottom levels of the plant stand corresponding to the strong light gradients occurring in it. We compared these data to results obtained from maize seedlings grown under artificial light sources preferentially exciting either photosystem II or photosystem I. In C3 plants, this light system induces redox signals within the photosynthetic electron transport chain which trigger state transitions and differential phosphorylation of LHCII (light harvesting complexes of photosystem II). The LTR to these redox signals induces changes in the accumulation of plastid psaA transcripts, in chlorophyll (Chl) fluorescence values F\\rm s/F\\rm m, in Chl a/b ratios and in transient starch accumulation in C3 plants. Maize seedlings grown in this light system exhibited a pronounced ability to perform both short-term and long-term acclimation at the level of psaA transcripts, Chl fluorescence values F\\rm s/F\\rm m and Chl a/b ratios. Interestingly, maize seedlings did not exhibit redox-controlled variations of starch accumulation probably because of its specific differences in energy metabolism. In summary, the artificial laboratory light system was found to be well-suited to mimic field light conditions and provides a physiological tool for studying the molecular regulation of the LTR of maize in more detail. PMID:24062753

Hirth, Matthias; Dietzel, Lars; Steiner, Sebastian; Ludwig, Robert; Weidenbach, Hannah; and, Jeannette Pfalz; Pfannschmidt, Thomas

2013-01-01

130

A Comparison of Entomopathogenic Nematode Longevity in Soil under Laboratory Conditions  

PubMed Central

We compared the longevity of 29 strains representing 11 entomopathogenic nematode species in soil over 42 to 56 d. A series of five laboratory experiments were conducted with six to eight nematode strains in each and one or more nematode strains in common, so that qualitative comparisons could be made across experiments. Nematodes included Heterorhabditis bacteriophora (four strains), H. indica (Homl), H. marelatus (Point Reyes), H megidis (UK211), H. mexicana (MX4), Steinernema carpocapsae (eight strains), S. diaprepesi, S. feltiae (SN), S. glaseri (NJ43), S. rarum (17C&E), and S. riobrave (nine strains). Substantial within-species variation in longevity was observed in S. carpocapsae, with the Sal strain exhibiting the greatest survival. The Sal strain was used as a standard in all inter-species comparisons. In contrast, little intra-species variation was observed in S. riobrave. Overall, we estimated S. carpocapsae (Sal) and S. diaprepesi to have the highest survival capability. A second level of longevity was observed in H. bacteriophora (Lewiston), H. megidis, S. feltiae, and S. riobrave (3–3 and 355). Lower levels of survivability were observed in other H. bacteriophora strains (Hb, HP88, and Oswego), as well as S. glaseri and S. rarum. Relative to S. glaseri and S. rarum, a lower tier of longevity was observed in H. indica and H. marelatus, and in H. mexicana, respectively. Although nematode persistence can vary under differing soil biotic and abiotic conditions, baseline data on longevity such as those reported herein may be helpful when choosing the best match for a particular target pest. PMID:19259437

Shapiro-Ilan, David I.; Stuart, Robin J.; McCoy, Clayton W.

2006-01-01

131

Scale effect on runoff and soil loss control using rice straw mulch under laboratory conditions  

NASA Astrophysics Data System (ADS)

Amendments can control the runoff and soil loss by protecting soil surface. However, scale effects on runoff and soil loss control has not been considered yet. The present study has been formulated to determine the efficiency of two plot sizes of 6 and 0.25 m2 covered by straw mulch with rate of 0.5 kg m-2 in changing the time to runoff, runoff coefficient, sediment concentration and soil loss under laboratory conditions. The study has been conducted for a sandy-loam soil taken from summer rangeland, Alborz Mountains, Northern Iran under simulated rainfall intensities of 50 and 90 mm h-1 and in 3 replicates. The results of the study showed that the straw mulch had more significant effect in in reducing runoff coefficient, sediment concentration and soil loss at 0.25 m2 plot scale. The maximum effectiveness in time to runoff for both the scales, observed in rainfall intensity of 90 mm h-1. The maximum increasing and decreasing rates in time to runoff and runoff coefficient observed in the rainfall intensity of 90 mm h-1 with the amounts of 367.92 and 96.71% for 0.25 m2 plot and the amounts of 110.10 and 15.08% for 6 m2 plot respectively. The maximum change of soil loss in both the intensities of 50 and 90 mm h-1 occurred at 0.25 m2 plot with the amount of 100% whereas at 6 m2 plot, decreasing rates of soil loss for in both the intensities of 50 and 90 mm h-1 were 46.74 and 63.24%, respectively.

Sadeghi, S. H. R.; Gholami, L.; Sharifi Moghadam, E.; Khaledi Darvishan, A.

2014-10-01

132

Corrosion of aluminum and copper thin films under simulated atmospheric conditions in laboratory tests  

SciTech Connect

Corrosion characteristics of Al and Cu thin films have been studied in cyclic fog tests using tap water fog and fog created with 0.1% NaCl solution in tap water. Likewise, their corrosion features have been analyzed in continuous immersion testing in the laboratory in distilled water, tap water, in 0.1% NaCl and 3.5% NaCl solutions in distilled water. The corrosion potentials and the corrosion currents of these thin films change and reach steady state values after some time. However, steady state is not realized in 3.5% NaCl solutions. The corrosion current density data have been used to calculate lifetime of 1 {mu}m thick thin films of Al and Cu in the various tests, and assuming that the fog test data would hold under normal exposure conditions, life spans for these thin film sensor elements in actual exterior exposure have also been calculated. According to estimates, an Al-TF of about 1 {mu}m would last about 9 months in exterior exposure in chloride containing atmospheres, such as in the coastal regions, but would survive nearly 2 years in normal atmospheres not having acidic or chloride pollutants. On the contrary, 1 {mu}m thick Cu-TF would last only for about 2.5 months in chloride-laden environments, but would last for about 2 years in normal atmospheres. However, Cu-TF would be corroded off faster in slightly alkaline atmospheric condensate under total immersion situation. Lifetime estimates are presented and discussed.

Li, W.; Raman, A. [Louisiana State Univ., Baton Rouge, LA (United States). Mechanical Engineering Dept.; Diwan, R.; Bhattacharya, P.K. [Southern Univ., Baton Rouge, LA (United States)

1998-12-31

133

Effects of insemination and blood-feeding on locomotor activity of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) females under laboratory conditions  

PubMed Central

Background Dengue is an arbovirus disease transmitted by two Aedes mosquitoes: Ae. aegypti and Ae. albopictus. Virgin females of these two species generally show a bimodal and diurnal pattern of activity, with early morning and late afternoon peaks. Although some studies on the flight activity of virgin, inseminated and blood-fed Ae. aegypti females have been carried out under laboratory conditions, little is known about the effects of such physiological states on the locomotor activity of Ae. albopictus and Ae. aegypti females. The aim of this study was to analyze, under laboratory conditions, the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under LD 12:12, at 25°C. Methods Both Ae. albopictus and Ae. aegypti females were obtained from established laboratory colonies. Control groups were represented by virgin/unfed Ae. albopictus and Ae. aegypti females. Experiments were conducted under laboratory conditions, using an activity monitor that registers individual activity every thirty minutes. Results Virgin/unfed Ae. albopictus and Ae. aegypti females showed a diurnal and bimodal pattern of locomotor activity, with peaks at early morning and late afternoon. Insemination and blood-feeding significantly decreased the locomotor activity of Ae. aegypti females, but inseminated/blood-fed Ae. aegypti and Ae. albopictus females showed a similar significant decrease on the locomotor activity compared to virgin/unfed females. Conclusions This study is the first demonstration of the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under artificial conditions. Data suggest that Ae. albopictus and Ae. aegypti females respond in different ways to physiological status changes and such divergence between these two dengue vectors, associated with several ecological differences, could be related to the greater dengue vectorial capacity of Ae. aegypti in Americas in comparison to Ae. albopictus. PMID:24990394

2014-01-01

134

Juvenile development and growth patterns in the mud crab Eurytium limosum (Say, 1818) (Decapoda, Brachyura, Xanthidae) under laboratory conditions  

Microsoft Academic Search

The post?larval development of the mud crab Eurytium limosum was studied under laboratory conditions by using the offspring of ovigerous females collected at the Comprido River mangrove, SP, Brazil. The first crab stage is fully described and the juvenile development, until crab stage 10, is examined with emphasis on morphological change, sexual differentiation and growth patterns. The carapace of the

Fernanda jordão Guimarães

2005-01-01

135

Formation and maintenance of aggregations in walleye pollock, Theragra chalcogramma , larvae under laboratory conditions: role of visual and chemical stimuli  

Microsoft Academic Search

Although planktonic marine fish larvae are often distributed in aggregations, the role of behavioral responses to environmental factors in these aggregations is not well understood. This work examines, under laboratory conditions, the influence of visual and chemical stimuli in the formation and maintenance of aggregations in walleye pollock,Theragra chalcogramma, larvae. Larvae were exposed to a horizontal gradient of light (visual

Michael W. Davis; Bori L. Olla

1995-01-01

136

Determination of soil biodegradation half-lives from simulation testing under aerobic laboratory conditions: A kinetic model approach  

Microsoft Academic Search

A kinetic model approach for determination of biodegradation half-lives from soil simulation testing is presented. The model describes transformation of the parent compound to metabolites and formation of bound (non-extractable) residues as well as mineralization in soil under aerobic laboratory conditions. Experimental data for several pesticide compounds from various soil simulation tests are used for fitting kinetic rate constants. Formation

Michael Matthies; Johannes Witt; Jörg Klasmeier

2008-01-01

137

REARING OF RHYNCHOPHORUS FERRUGINEUS IN LABORATORY AND FIELD CONDITIONS FOR CARRYING OUT VARIOUS EFFICACY STUDIES USING EPNs  

Microsoft Academic Search

Methods for rearing of red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) in laboratory and field conditions were developed. Three mediums were tested for egg laying viz., cotton wool having 20 % honey solution, apple and sugarcane pieces. Cotton wool medium had highest numbers of laid eggs 230 ± 1.0. To observe percentage of hatching, four mediums were prepared viz., Petri

F. SHAHINA; J. SALMA; G. MEHREEN; M. I. BHATTI; K. A. TABASSUM

138

Survival and food choice of the grey field slug ( Deroceras reticulatum ) on three different seed types under laboratory conditions  

Microsoft Academic Search

In Ireland, the grey field slug (Deroceras reticulatum) is the predominant slug pest species in arable crops. It can cause enormous damage, but the knowledge about its feeding biology is limited.Adult species were reared under laboratory conditions, and the survival, feeding activity, and weight change of slugs when feed on maize, peas, or wheat seeds were investigated. An especially high

J. Gebauer

2002-01-01

139

Assessing the Exposure and Relative Sensitivity of Native Freshwater Mussels to Environmental Stressors and Laboratory Conditions  

EPA Science Inventory

1. Expands the database for pesticide toxicity on native freshwater mussels. 2. Aids in determining any potential differences in toxic sensitivity of gravid female mussel attributed to age and laboratory holding times. 3. Aids in determining potential differences in juvenile ...

140

42 CFR 493.1453 - Condition: Laboratories performing high complexity testing; clinical consultant.  

Code of Federal Regulations, 2010 CFR

...performing high complexity testing; clinical consultant. 493.1453 Section 493.1453 ...performing high complexity testing; clinical consultant. The laboratory must have a clinical consultant who meets the requirements of §...

2010-10-01

141

Comparative evaluation of laboratory compaction devices based on their ability to produce mixtures with engineering properties similar to those produced in the field  

E-print Network

Sets Test Cores and Specimens Compare Data Sets Figure 1. Flow chart of compaction study sample sets of cores and laboratory-prepared samples were tested for indirect tensile strength, indirect tensile creep, and diametral resilient modulus at 77... vibratory kneading compactor, and the double plunger or static compressive load. Double Plunger: The double plunger consists of a static load applied to the specimen by means of a compression testing machine. Metal followers, employed as free fitting...

Consuegra, Alberto Enrique

2012-06-07

142

Methane hydrate behavior when exposed to a 23% carbon dioxide 77% nitrogen gas under conditions similar to the ConocoPhillips 2012 Ignik Sikumi Gas Hydrate Field Trial  

NASA Astrophysics Data System (ADS)

In-situ replacement of methane hydrate by carbon dioxide hydrate is considered to be a promising technique for producing natural gas, while simultaneously sequestering greenhouse gas in deep geological formations. For effective application of this technique in the field, kinetic models of gas exchange rates in hydrate under a variety of environmental conditions need to be established, and the impact of hydrate substitution on geophysical (seismic) properties has to be quantified in order to optimize monitoring techniques. We performed a series of laboratory tests in which we monitored changes in methane hydrate-bearing samples while a nitrogen/carbon dioxide gas mixture was flowed through. These experiments were conducted to gain insights into data obtained from a field test in which the same mixture of carbon dioxide and nitrogen was injected into a methane hydrate-bearing unit beneath the north slope of the Brooks Range in northern Alaska (ConocoPhillips 2012 Ignik Sikumi gas hydrate field trial). We have measured the kinetic gas exchange rate for a range of hydrate saturations and different test configurations, to provide an estimate for comparison to numerical model predictions. In our tests, the exchange rate decreased over time during the tests as methane was depleted from the system. Following the elution of residual gaseous methane, the exchange rate ranged from 3.8×10-7 moles methane/(mole water*s) to 5×10-8 moles methane/(mole water*s) (Note that in these rates, the moles of water refers to water originally held in the hydrate.). In addition to the gas exchange rate, we also monitored changes in permeability occurring due to the gas substitution. Further, we determined the seismic P and S wave velocities and attenuations using our Split Hopkinson Resonant Bar apparatus (e.g. Nakagawa, 2012, Rev. Sci. Instr.). In addition to providing geophysical signatures, changes in the seismic properties can also be related to changes in the mechanical strength of the hydrate-bearing sand resulting from exposure to the mixed gas. Upon introduction of the mixed gas, the sample became less stiff and wave attenuation increased, indicating the presence of liquid water between mineral grains and hydrate. Slow dissociation of hydrate conducted in this experiment showed a range of hydrate stability conditions as the gas composition changed from dissociation and dilution of the previously injected nitrogen.

Borglin, S. E.; Kneafsey, T. J.; Nakagawa, S.

2013-12-01

143

The quantitative genetics of wing dimorphism under laboratory and ‘field’ conditions in the cricket Gryllus pennsylvanicus  

Microsoft Academic Search

Laboratory estimates of the heritability of threshold traits indicate a typically large additive genetic component. In natural populations, it has been suggested that the heritability might be considerably reduced owing to environmental variation. No test of this hypothesis for threshold traits has been undertaken. In this paper, such a test is reported using wing dimorphism in the cricket, Gryllus pennsylvanicus.

Derek A Roff; Andrew M Simons

1997-01-01

144

INTERACTIONS BETWEEN BACILLUS THURINGIENSIS SUBSP. ISRAELENSIS AND FATHEAD MINNOWS, PIMEPHALES PROMELAS RAFINESQUE, UNDER LABORATORY CONDITIONS  

EPA Science Inventory

Interactions between Bacillus thuringiensis subsp. israelensis and fathead minnows, Pimephales promelas, were studied in laboratory exposures to two commercial formulations, Vectobac-G and Mosquito Attack. ortality among fatheads exposed to 2.0 x 10 6 to 6.5 x 10 6 CFU/ml with bo...

145

The Eye of the Laboratory Mouse Remains Anatomically Adapted for Natural Conditions  

PubMed Central

Evolutionary effects of domestication have been demonstrated for several body systems, including the eye, and for several vertebrate species, including the mouse. Given the importance of the laboratory mouse to vision science, we wished to determine whether the anatomical and histological features of the eyes of laboratory mice are distinct from those of their naturally adapted, wild counterparts. We measured dimensions and masses of whole eyes and lenses from a wild population plus three inbred strains (C57BL/6J, NZB/BINJ, and DBA/1J) of the house house, Mus musculus, as well as wild and outbred laboratory-domesticated stock of the deer mouse, Peromyscus maniculatus. Histological preparations from these eyes were used to determine outer nuclear layer thickness, linear density of the ganglion cell layer, and for indirect immunofluorescence evaluation of cone opsin expression. For all of these traits, no statistically significant differences were found between any laboratory strain and its wild counterpart. The evolutionary effects of domestication of mice therefore do not include changes to the eye in any variable measured, supporting the continued use of this animal as a model for a naturally adapted visual system. PMID:16219997

Shupe, Jonathan M.; Kristan, Deborah M.; Austad, Steven N.; Stenkamp, Deborah L.

2008-01-01

146

Carbon mineralization dynamics in soils amended with meat meals under laboratory conditions  

Microsoft Academic Search

Meat and bone meal (MBM) is obtained from the wastes produced during slaughtering operations. Its high concentration of N and P makes it interesting as an organic fertiliser but its use in soil has been barely studied previously. In this work four laboratory experiments were performed to study the influence of different variables (MBM composition, rate of application, temperature of

M. L. Cayuela; T. Sinicco; F. Fornasier; M. A. Sanchez-Monedero; C. Mondini

2008-01-01

147

Overview of geological and hydrogeological conditions of the Äspö hard rock laboratory site  

Microsoft Academic Search

The site of the underground facility, the Äspö Hard Rock Laboratory, was excavated at a depth of 450 m below the island of Äspö and has been extensively investigated by geological, hydrogeological and hydrochemical methods as part of the geoscientific research for disposal of nuclear waste in Sweden. The geological history of the area dates back to 1.85 Ga and

Roy Stanfors; Ingvar Rhén; Eva-Lena Tullborg; Peter Wikberg

1999-01-01

148

LABORATORY AND FIELD STUDIES ON BTEX BIODEGRADATION IN A FUEL-CONTAMINATED AQUIFER UNDER DENITRIFYING CONDITIONS  

EPA Science Inventory

Laboratory studies were conducted in conjunction with a field demonstration project on nitrate-mediated biorestoration of a fuel-contaminated aquifer at a U.S. Coast Guard facility in Traverse City, MI. icrocosms were prepared under either aerobic or strictly anaerobic, denitrify...

149

The effect of chemicals released by Gammarus lacustris on the depth distribution of Arctodiaptomus salinus in laboratory conditions  

Microsoft Academic Search

The effect of treatment water containing chemicals released by Gammarus lacustris or crushed\\/injured Arctodiaptomus salinus induced changes in vertical distribution of Arctodiaptomus in laboratory conditions. With food concentration in the medium corresponding to the maximum of algae concentration in Shira lake, A. salinus in an experimental vessel was situated higher than in the control. Average population depth of A. salinus decreased as

Yegor S. Zadereev; Michael V. Gubanov

2002-01-01

150

Monitoring of naturally acquired and artificially induced immunity to Amblyomma variegatum and Rhipicephalus appendiculatus ticks under field and laboratory conditions  

Microsoft Academic Search

The ability of rabbits, goats and cattle to acquire immunity to the ixodid ticksAmblyomma variegatum andRhipicephalus appendiculatus was studied under laboratory and field conditions. Rabbits were successfully immunized with crude salivary gland extract (SGE) and midgut extract (ME) obtained from flat or partly fed femaleR. appendiculatus ticks. The lowest numbers of larvae were produced by females fed on rabbits immunized

F. Jongejan; R. G. Pegram; D. Zivkovic; E. J. Hensen; E. T. Mwase; M. J. C. Thielemans; A. Cossé; T. A. Niewold; Ashrafel Said; G. Uilenberg

1989-01-01

151

Influence of Water Hardness on Accumulation and Elimination of Cadmium in Two Aquatic Mosses Under Laboratory Conditions  

Microsoft Academic Search

.   This study investigated the effect of water hardness on the accumulation and elimination of cadmium (Cd) by two aquatic\\u000a mosses, Fontinalis dalecarlica and Platyhypnidium riparioides, under laboratory conditions. The two mosses were exposed to nominal Cd concentrations of 0, 0.8, 2, and 10 ?g?·?L?1, which includes the concentration range generally found in nature. The influence of three levels of

C. Gagnon; G. Vaillancourt; L. Pazdernik

1998-01-01

152

Oven-dried mosses as tools for trace element detection in polluted waters: A preliminary study under laboratory conditions  

Microsoft Academic Search

The concentration of 11 trace elements, plus Ca, Mg, Na and K was measured in moss bags of living and dead (oven-dried at 105°C) Platyhypnidium riparioides after a 1-week exposure to tap water, and to 0.21, 1.0, 2.5 and 4.0 ?M solutions under laboratory conditions, with the aim of (1) observing the accumulation curves and (2) performing a statistical comparison in

M. Cesa; A. Bizzotto; C. Ferraro; F. Fumagalli; P. Luigi Nimis

2011-01-01

153

Study of the efficacy of a Wheaton coated bottle with permethrin and deltamethrin in laboratory conditions and a WHO impregnated paper with bendiocarb in field conditions  

PubMed Central

Objective To determine the efficacy of WHO impregnated paper and CDC coated bottle based on number of storage days and number of times of consecutive use, in the assessment of insecticide vector susceptibility tests in laboratory and field conditions. Methods Larvae and pupae of Anopheles gambiae s.l. mosquitoes were collected from the breeding sites in Seme-Kpodji and Cotonou districts in Southern Benin in April 2013 during the first rainy season. Anopheles gambiae s.l. mosquitoes were also collected from the breeding sites in Parakou district in Northern Benin in May 2013 at the beginning of the rainy season. Susceptibility tests were done using impregnated paper with bendiocarb (0.1%) following WHO protocol and stock solutions of permethrin (21.5 µg per bottle) and deltamethrin (12.5 µg per bottle) following CDC protocol on unfed female mosquitoes aged 2–5 days old. These bioassays were repeated a certain number of times. The temperature and relative humidity were monitored and recorded during the susceptibility tests. Results This study showed that a WHO impregnated paper with bendiocarb could be used four times during four consecutive days in field conditions. Regarding a Wheaton coated bottle with permethrin or deltamethrin, they could be used at least three times during four consecutive days in laboratory conditions. Conclusions The day storage and the number of times that a WHO impregnated paper and a CDC coated bottle maintained their efficacy are useful in the assessment of insecticide vectors susceptibility tests. PMID:25182952

Aizoun, Nazaire; Azondekon, Roseric; Aikpon, Rock; Gnanguenon, Virgile; Osse, Razaki; Asidi, Alex; Akogbeto, Martin

2014-01-01

154

Similar names for similar biologics.  

PubMed

Approval of the first biosimilar in the USA may occur by the end of 2014, yet a naming approach for biosimilars has not been determined. Biosimilars are highly similar to their biologic reference product but are not identical to it, because of their structural complexity and variations in manufacturing processes among companies. There is a need for a naming approach that can distinguish a biosimilar from its reference product and other biosimilars and ensure accurate tracing of adverse events (AEs) to the administered product. In contrast, generic small-molecule drugs are identical to their reference product and, therefore, share the same nonproprietary name. Clinical trials required to demonstrate biosimilarity for approval may not detect rare AEs or those occurring after prolonged use, and the incidence of such events may differ between a biosimilar and its reference product. The need for precise biologic identification is further underscored by the possibility of biosimilar interchangeability, a US designation that will allow substitution without prescriber intervention. For several biologics, the US Food and Drug Administration (FDA) has used a naming approach that adds a prefix to a common root nonproprietary name, enabling healthcare providers to distinguish between products, avoid medication errors, and facilitate pharmacovigilance. We recommend that the FDA implement a biosimilars naming policy that likewise would add a distinguishable prefix or suffix to the root nonproprietary name of the reference product. This approach would ensure that a biosimilar could be distinguished from its reference product and other biosimilars in patient records and pharmacovigilance databases/reports, facilitating accurate attribution of AEs. PMID:25001080

Casadevall, Nicole; Felix, Thomas; Strober, Bruce E; Warnock, David G

2014-10-01

155

Population growth of Pieris brassicae (L.) (Lepidoptera: Pieridae) on different cole crops under laboratory conditions  

Microsoft Academic Search

The effect of different host plants including cabbage, cauliflower, mustard, radish, and broccoli on biological parameters\\u000a of Pieris brassicae (L.) was studied in the laboratory at 28°C, 65 ± 5% RH and 12L:12D photoperiod. Duration of each life stage, longevity, the\\u000a intrinsic rate of natural increase (r\\u000a m), net reproductive rate (R\\u000a 0), mean generation time (T), doubling time (DT), and finite

Fazil Hasan; M. Shafiq Ansari

2011-01-01

156

Condition assessment of the Los Alamos National Laboratory radioactive liquid waste collection system  

Microsoft Academic Search

The radioactive liquid waste collection system (RLWCS) at Los Alamos National Laboratory (LANE) is a site-wide double-encased piping system installed in 1982 that allows radioactive liquid waste (RLW) producing facilities to gravity drain their waste to the radioactive liquid waste treatment facility (RLWTF) through a system of underground high-density polyethylene (HDPE) pipes and vaults. The RLWCS stretches approximately four miles

G. L. Edgemon; W. D. Moss; V. P. Worland

2004-01-01

157

Social influences during song development in the song sparrow: a laboratory experiment simulating field conditions  

Microsoft Academic Search

Oscine songbirds are exposed to many more songs than they keep for their final song repertoire and little is known about how a bird selects the particular song(s) to sing as an adult. We simulated in the laboratory the key variables of the natural song learning environment and examined the song selection process in nine hand-reared male song sparrows,Melospiza melodia

J. Cully Nordby; S. Elizabeth Campbell; John M. Burt; Michael D. Beecher

2000-01-01

158

Vibrio ordalii antimicrobial susceptibility testing--modified culture conditions required and laboratory-specific epidemiological cut-off values.  

PubMed

The present study aimed to determine oxytetracycline (OTC), florfenicol (FLO) and oxolinic acid (OXO) MICs and zone diameters for 24 Chilean Vibrio ordalii isolates using the methods for broth dilution susceptibility testing of bacteria isolated from aquatic animals and the methods for antimicrobial disk susceptibility testing of bacteria isolated from aquatic animals guidelines published by the Clinical Laboratory Standards Institute (CLSI). The results were then used in a normalized resistance interpretation (NRI) analysis to establish tentative laboratory-specific epidemiological cut-off (ECOFF) values. MIC results were similar at the two tested temperatures (22 °C and 18 °C). At 18 °C, the NRI analysis of OTC, FLO and OXO MIC data calculated laboratory-specific ECOFF values and non-wild-type (NWT) rates to be ?4 mg/l (24%), ?16 mg/l (4%) and ?8 mg/l (25%), respectively. Tests performed with all V. ordalii isolates following the officially recommended incubation temperature (22 °C) revealed difficulties in measuring inhibition zone diameters. When disk diffusion tests were performed using Mueller-Hinton agar with 1% NaCl (MHA-1) at 18 °C the inhibition zone diameter distributions showed the formation of WT populations which could be defined using NRI analysis. For OTC the laboratory-specific ECOFF value was ?38 mm with NWT rate of 16.7%. For FLO and OXO, the laboratory-specific ECOFF values were ?38 and ?40, respectively, generating NWT rates of 25 and 46%, respectively. Although the CLSI suggests testing Vibrio spp. on MHA-1 at 22 °C, we found measurements of the 24 isolates were better defined and normally distributed at 18 °C. This is the first study determining the MIC and disk diffusion test of V. ordalii isolated from diseased salmonids, where laboratory-specific ECOFF values could be established. Also resistance to OTC, FLO and OXO among some Chilean isolates was demonstrated. PMID:23726222

Poblete-Morales, Matías; Irgang, Rute; Henríquez-Núñez, Hernán; Toranzo, Alicia E; Kronvall, Göran; Avendaño-Herrera, Ruben

2013-08-30

159

Conditions for building a community of practice in an advanced physics laboratory  

NASA Astrophysics Data System (ADS)

We use the theory of communities of practice and the concept of accountable disciplinary knowledge to describe how a learning community develops in the context of an upper-division physics laboratory course. The change in accountable disciplinary knowledge motivates students' enculturation into a community of practice. The enculturation process is facilitated by four specific structural features of the course and supported by a primary instructional choice. The four structural features are "paucity of instructor time," "all in a room together," "long and difficult experiments," and "same experiments at different times." The instructional choice is the encouragement of the sharing and development of knowledge and understanding by the instructor. The combination of the instructional choice and structural features promotes the development of the learning community in which students engage in authentic practices of a physicist. This results in a classroom community that can provide students with the opportunity to have an accelerated trajectory towards being a more central participant of the community of a practice of physicists. We support our claims with video-based observations of laboratory classroom interactions and individual, semistructured interviews with students about their laboratory experiences and physics identity.

Irving, Paul W.; Sayre, Eleanor C.

2014-06-01

160

Response of the green alga Oophila sp., a salamander endosymbiont, to a PSII-inhibitor under laboratory conditions.  

PubMed

In a rare example of autotroph-vertebrate endosymbiosis, eggs of the yellow-spotted salamander (Ambystoma maculatum) are colonized by a green alga (Oophila sp.) that significantly enhances salamander development. Previous studies have demonstrated the potential for impacts to the salamander embryo when growth of the algae is impaired by exposure to herbicides. To further investigate this relationship, the authors characterized the response of the symbiotic algae (Oophila sp.) alone to the photosystem II (PSII) inhibitor atrazine under controlled laboratory conditions. After extraction of the alga from A. maculatum eggs and optimization of culturing conditions, 4 toxicity assays (96 h each) were conducted. Recovery of the algal population was also assessed after a further 96 h in untreated media. Average median effective concentration (EC50) values of 123 µg L(-1) (PSII yield), 169 µg L(-1) (optical density), and 299 µg L(-1) (growth rate) were obtained after the 96-h exposure. Full recovery of exposed algal populations after 96 h in untreated media was observed for all endpoints, except for optical density at the greatest concentration tested (300 µg L(-1) ). Our results show that, under laboratory conditions, Oophila sp. is generally less sensitive to atrazine than standard test species. Although conditions of growth in standard toxicity tests are not identical to those in the natural environment, these results provide an understanding of the tolerance of this alga to PSII inhibitors as compared with other species. PMID:24782078

Baxter, Leilan; Brain, Richard; Rodriguez-Gil, Jose Luis; Hosmer, Alan; Solomon, Keith; Hanson, Mark

2014-08-01

161

Laboratory evaluation and application of microwave absorption properties under simulated conditions for planetary atmospheres  

NASA Technical Reports Server (NTRS)

Radio absorptivity data for planetary atmospheres obtained from spacecraft radio occultation experiments and earth-based radio astronomical observations can be used to infer abundances of microwave absorbing atmospheric constituents in those atmospheres, as long as reliable information regarding the microwave absorbing properties of potential constituents is available. Work performed has shown that laboratory measurements of the millimeter-wave opacity of ammonia between 7.5 mm and 9.3 mm and also at the 3.2 mm wavelength require a different lineshape to be used in the theoretical prediction for millimeter-wave ammonia opacity than was previously used. The recognition of the need to make such laboratory measurements of simulated planetary atmospheres over a range of temperatures and pressures which correspond to the altitudes probed by both radio occultation experiments and radio astronomical observations, and over a range of frequencies which correspond to those used in both radio occultation experiments and radio astronomical observations, has led to the development of a facility at Georgia Tech which is capable of making such measurements. It has been the goal of this investigation to conduct such measurements and to apply the results to a wide range of planetary observations, both spacecraft and earth-based, in order to determine the identity and abundance profiles of constituents in those planetary atmospheres.

Steffes, Paul G.

1989-01-01

162

Spectroscopics database for warm Xenon and Iron in Astrophysics and Laboratory Astrophysics conditions  

NASA Astrophysics Data System (ADS)

The main contribution to spectral properties of astrophysics mixtures come often from Iron. On the other hand, in the so-called domain of ``Laboratory Astrophysics,'' where astrophysics phenomena are scaled down to the laboratory, Xenon (and Argon) are commonly used gases. At so called ``warm'' temperatures (T=5-50eV), L-shell Iron and M-shell Xenon present a very large number of spectral lines, originating from billions of levels. More often than not, Local Thermodynamical Equilibrium is assumed, leading to noticeable simplification of the computation. Nevertheless, complex and powerful atomic structure codes are required. We take benefit of powerful statistics and numerics, included in our atomic structure codes, STA[1] and HULLAC[2], to generate the required spectra. Recent improvements in both fields (statistics, numerics and convergence control) allow obtaining large databases (ro x T grid of > 200x200 points, and > 10000 frequencies) for temperature down to a few eV. We plan to port these improvements in the NLTE code SCROLL[3]. [1] A.Bar-Shalom, et al, Phys. Rev. A 40, 3183 (1989) [2] M.Busquet,et al, J.Phys. IV France 133, 973-975 (2006); A.Bar-Shalom, M.Klapisch, J.Oreg, J.Oreg, JQSRT 71, 169, (2001) [3] A.Bar-Shalom, et al, Phys. Rev. E 56, R70 (1997)

Busquet, Michel; Klapisch, Marcel; Bar-Shalom, Avi; Oreg, Josse

2010-11-01

163

A laboratory for instruction and research in air conditioning and refrigeration  

E-print Network

A LARORATORY FOR INSTRUCTION AND RESEARCH IN AIR CONDITIONING AND REFRIGERATION A Thesis RAY ALLISON HALL Approued as to style and content by Chairman of Cosa. ittee August 1$50 A IABQRATORY FOR INSTRUCTION AI'H3 RESEARCH IN AIR CONDITIONING... Al'G3 RE. ""RIGKlkTION Ray Allison Eall I ~ A Thesis Submitted to the Graduate School of the Agricultural and Nechanfcal College of' Texas in partiol f'ulfillment of' the requirements for the degree of MASTER OF SCIENCE lBajor Sub j oct...

Hall, Ray Allison

2012-06-07

164

Accumulation and Elimination of Enrofloxacin and Ciprofloxacin in Tissues of Shrimp Litopenaeus vannamei under Laboratory and Farm Conditions  

PubMed Central

This study aimed to quantify the accumulation and elimination of Enrofloxacin (ENRO) and Ciprofloxacin (CIPRO) in cultivated Litopenaeus vannamei under controlled laboratory and farm conditions. Laboratory- and farm-raised shrimp were given feed supplemented with 200?mg/kg ENRO for 14 days, followed by a 16-day diet without antibiotics. The levels of ENRO and CIPRO were analyzed by High Performance Liquid Chromatography (HPLC). In the laboratory, ENRO concentrations in the muscle and hepatopancreas reached a maximum (Cmax) of 0.54 ± 0.26??g/g and 3.52 ± 1.9??g/g, respectively; Cmax values for CIPRO in the laboratory were 0.18 ± 0.13??g/g (muscle) and 1.05 ± 0.20??g/g (hepatopancreas). In farmed shrimp, Cmax values for ENRO were 0.36 ± 0.17??g/g muscle and 1.60 ± 0.82??g/g in the hepatopancreas; CIPRO Cmax values were 0.03 ± 0.02??g/g (muscle) and 0.36 ± 0.08??g/g (hepatopancreas). Two to fourteen days were necessary to eliminate both antibiotics from muscular tissue and four to more fourteen days for complete elimination of the antibiotics from the hepatopancreas. These results should be considered in terms of minimum concentrations necessary to inhibit Vibrio bacteria to determine whether the current use of this antibiotic is effective in controlling disease. PMID:22779008

Flores-Miranda, Brisa Marisol; Espinosa-Plascencia, Angelica; Gomez-Jimenez, Silvia; Lopez-Zavala, Alonso Alexis; Gonzalez-Carrillo, Hayde Hayamai; Bermudez-Almada, Maria del Carmen

2012-01-01

165

Snapping shrimp prefer natural as opposed to artificial materials as their habitat in laboratory conditions  

NASA Astrophysics Data System (ADS)

This study analyzed the habitat selection behavior of the snapping shrimp, Alpheus spp., comparing natural shelters (Rocks with oysters attached on the surface Sh; rocks with smooth surface, Ro and coral rubble, Co with plastic bottle. Controlled laboratory experiments were conducted to assess the habitat preference, effect of photoperiod and shrimp orientation at shelter. The current study indicated that snapping shrimp preferred natural materials but rejected plastic bottle as their shelter. Among the natural shelters, coral rubble was the most preferred habitat followed by shell and rock. Photoperiod showed minimum effect on the shrimp where they spend most of the time inside and underneath the shelters. In conclusion the current study showed that snapping shrimp preferred coral rubble as opposed to other natural material and plastic bottle. The result also suggested that plastic debris in the marine environment is not an alternative habitat for snapping shrimp.

Sim, Lai Kean; Ghazali, Shahriman M.

2014-09-01

166

Biological effects of pyrimethinal on aquatic worms (Tubifex tubifex) under laboratory conditions.  

PubMed

Laboratory studies were conducted to determine the effects of different concentrations of pyrimethinal on protein contents, and some oxidative stress in Tubifex tubifex after an exposure of 2, 4, and 7 days. Residues of the fungicide were followed in water and in the worms. In water, pyrimethinal concentration decreased slowly (maximum -6.4 % ± 0.8 % after 2 days for 25 mg L(-1)). In the worms, it increased after 4 days and decreased thereafter. LC50 values were between 49.2 ± 0.58 and 39.5 ± 0.95 mg L(-1) depending on exposure time. The activity of catalase increased in response to the fungicide after 2 days of exposure to 25 mg L(-1) of pyrimethinal (+90 %). The highest decrease of glutathione-S-transferase activity (-29.7 %) was found after 7 days in the presence of 25 mg L(-1). PMID:24213591

Mosleh, Yahia Youssef; Mofeed, Jelan; Afifi, Mohamed; Almaghrabi, Omar A

2014-01-01

167

Predation by odonate nymphs on larval razorback suckers (Xyrauchen texanus) under laboratory conditions  

USGS Publications Warehouse

High larval mortality has plagued efforts to raise razorback suckers (Xyrauchen texanus) in a Lake Mohave, Arizona-Nevada backwater. Observations indicate odonate nymph densities may be high enough to impact larval survival. In laboratory tests conducted in aquaria, damselfly (Coenagrionidae: Enallagma sp.) and dragonfly (Libellulidae: Tramea sp.) nymphs consumed 81% and 76% respectively of 11.8 ± 0.7 mm total length larval razorbacks in 7 days compared to 12% mortality in controls. Larger razorback larvae (14 to 15 mm TL) were less susceptible than smaller fish, showing 53% mortality versus 18% in controls. Extensive growth of sago pondweed (Potamogeton pectinatus) may exacerbate predation effects in the backwater, by allowing odonates access to more of the water column.

Horn, Michael J.; Marsh, Paul C.; Mueller, Gordon; Burke, Tom

1994-01-01

168

Efficacy of pesticide mixtures against the western flower thrips (Thysanoptera: Thripidae) under laboratory and greenhouse conditions.  

PubMed

Western flower thrips, Frankliniella occidentalis Pergande is a commonly encountered and economically important insect pest of greenhouses. Greenhouse producers typically apply pesticides as mixtures to mitigate western flower thrips populations; however, there is limited information available on the compatibility and efficacy of commonly used pesticide mixtures. This study assessed nine binary and three tertiary pesticide mixtures used in greenhouses which included pesticides containing abamectin, acephate, azadirachtin, bifenazate, bifenthrin, fenpropathrin, imidacloprid, novaluron, pymetrozine, and spinosad. Compatibility was determined for the binary pesticide mixtures using jar tests. In addition, the binary mixtures were applied to nine horticultural plant species to determine phytotoxicity based on visual appearance assessed 7 d after treatment. Bean-dip bioassays were performed in a laboratory using green bean (Phaseolus vulgaris L.) to determine LC50 values for each individual pesticide and the mixtures to establish whether the mixtures were synergistic, antagonistic, or there was no effect. The mortality of western flower thrips was assessed after 24 h, and LC50 values were calculated. Furthermore, semifield bioassays were performed in greenhouses for binary and tertiary mixtures to evaluate the efficacy (based on percent mortality) of the pesticide mixtures against western flower thrips. Results indicated that all binary mixtures were visibly compatible, and not phytotoxic to any of the plant species evaluated. Combination index calculations based on laboratory results indicated most of the binary mixtures were synergistic; however, the mixture containing spinosad + bifenazate appeared to be antagonistic against western flower thrips. The semifield bioassays demonstrated significantly reduced efficacy associated with mixtures containing azadirachtin, however, all binary mixtures provided approximately 80% western flower thrips mortality. PMID:23448038

Willmott, Amy L; Cloyd, Raymond A; Zhu, Kun Yan

2013-02-01

169

Parametrization of turbulence models using 3DVAR data assimilation in laboratory conditions  

NASA Astrophysics Data System (ADS)

In this research the 3DVAR data assimilation scheme is implemented in the numerical model DIVAST in order to optimize the performance of the numerical model by selecting an appropriate turbulence scheme and tuning its parameters. Two turbulence closure schemes: the Prandtl mixing length model and the two-equation k-? model were incorporated into DIVAST and examined with respect to their universality of application, complexity of solutions, computational efficiency and numerical stability. A square harbour with one symmetrical entrance subject to tide-induced flows was selected to investigate the structure of turbulent flows. The experimental part of the research was conducted in a tidal basin. A significant advantage of such laboratory experiment is a fully controlled environment where domain setup and forcing are user-defined. The research shows that the Prandtl mixing length model and the two-equation k-? model, with default parameterization predefined according to literature recommendations, overestimate eddy viscosity which in turn results in a significant underestimation of velocity magnitudes in the harbour. The data assimilation of the model-predicted velocity and laboratory observations significantly improves model predictions for both turbulence models by adjusting modelled flows in the harbour to match de-errored observations. Such analysis gives an optimal solution based on which numerical model parameters can be estimated. The process of turbulence model optimization by reparameterization and tuning towards optimal state led to new constants that may be potentially applied to complex turbulent flows, such as rapidly developing flows or recirculating flows. This research further demonstrates how 3DVAR can be utilized to identify and quantify shortcomings of the numerical model and consequently to improve forecasting by correct parameterization of the turbulence models. Such improvements may greatly benefit physical oceanography in terms of understanding and monitoring of coastal systems and the engineering sector through applications in coastal structure design, marine renewable energy and pollutant transport.

Olbert, A. I.; Nash, S.; Ragnoli, E.; Hartnett, M.

2013-12-01

170

The impact of insecticides to local honey bee colony Apis cerana indica in laboratory condition  

NASA Astrophysics Data System (ADS)

Heavy use of insecticides considered as one of common practice at local farming systems. Even though many Indonesian researchers had stated the possible detrimental effect of insecticide on agriculture environment and biodiversity, researches on this subject had been neglected. Therefore, our purpose in this research is observing the impact of insecticides usage by farmer to non target organisme like local honey bee (Apis cerana indica), which commonly kept in area near agriculture system. This research consisted of field observations out at Ciburial, Dago Pakar, Bandung and laboratory tests at School of Life Sciences and Technology, Institut Teknologi Bandung. The field observations recorded visited agriculture corps and types of pollen carried by bees to the nest while laboratory test recorderd the effect of common insecticide to mortality and behavior of honey bees. Three types of insecticides used in this research were insecticides A with active agent Chlorantraniliprol 50 g/l, insecticide B with active agent Profenofos 500 g/l, and insecticides C with active agent Chlorantraniliprol 100 g/l and ?-cyhalotrin 50g/l. The results show that during one week visit, wild flower, Wedelia montana, visited by most honey bees with average visit 60 honey bees followed by corn, Zea mays, with 21 honey bees. The most pollen carried by foragers was Wedelia montana, Calliandra callothyrsus, and Zea mays. Preference test show that honeybees tend move to flowers without insecticides as the preference to insecticides A was 12.5%, insecticides B was 0%, and insecticides was C 4.2%. Mortality test showed that insecticides A has LD50 value 0.01 ?g/?l, insecticide B 0.31 ?g/?l, and insecticides C 0.09 ?g/?l which much lower than suggested dosage recommended by insecticides producer. This research conclude that the use of insecticide could lower the pollination service provide by honey bee due to low visitation rate to flowers and mortality of foraging bees.

Putra, Ramadhani E.; Permana, Agus D.; Nuriyah, Syayidah

2014-03-01

171

Life cycle and host specificity of Amblyomma triste (Acari: Ixodidae) under laboratory conditions.  

PubMed

We report biological data of two generations of Amblyomma triste in laboratory and compared the suitability of different host species. Infestations by larval and nymphal stages were performed on guinea pigs (Cavia porcellus), chickens (Gallus gallus), rats (Rattus norvegicus), rabbits (Oryctolagus cuniculus), wild mice (Calomys callosus), dogs (Canis familiaris) and capybaras (Hydrochaeris hydrochaeris). Infestations by adult ticks were performed on dogs, capybaras and rabbits. Tick developmental periods were observed in an incubator at 27 degrees C and RH 90%. Guinea pigs were the most suitable hosts for larvae and nymphs, followed by chickens. The remaining host species were less suitable for immature ticks as fewer engorged ticks were recovered from them. Mean larval feeding periods varied from 3.8 to 4.7 d between different host species. Mean larval premolt periods ranged from 8.9 to 10.4 d. Nymphal mean feeding periods varied from 4.2 to 6.2 d for ticks fed on different host species. Premolt period of male nymphs (mean: 15.4 d) was significantly longer than that of female nymphs (14.7 d). Female nymphs were significantly heavier than male nymphs. The overall sex ratio of the adult ticks emerged from nymphs was 0.9:1 (M:F). Capybaras were the most suitable host for the tick adult stage as significantly more engorged females were recovered from them and these females were significantly heavier than those recovered from dogs or rabbits. The life cycle of A. triste in laboratory could be completed in an average period of 155 d. The potential role of guinea pigs, birds and capybaras, as hosts for A. triste in nature, is discussed. PMID:14756395

Labruna, Marcelo B; Fugisaki, Eric Y M; Pinter, Adriano; Duarte, José Maurício B; Szabó, Matias J P

2003-01-01

172

Activity, aggression, and habitat use of ruffe (Gymnocephalus cernuus) and round goby (Apollonia melanostoma) under laboratory conditions  

USGS Publications Warehouse

Potential negative ecological interactions between ruffe Gymnocephalus cernuus and round goby Apollonia melanostoma (formerly Neogobius melanostomus) might affect the colonization dynamics of these invasive species where they are sympatric in the Great Lakes. In order to determine the potential for ecological interactions between these species, we examined the activity, aggression, and habitat use of round gobies and ruffe in single species and mixed species laboratory experiments. Trials included conditions in which food was concentrated (in light or darkness) or scattered. Results showed that ruffe were more active than gobies, particularly when food was scattered. Activity of both species was significantly lower during darkness. Round gobies were significantly more aggressive than ruffe, and total aggression was lower in mixed species trials. Habitat use by ruffe and round gobies overlapped considerably, but we observed significant differences between species in their use of specific habitats that depended on experimental conditions. Overall, ruffe used open habitats more often than did round gobies, primarily when food was scattered. Round gobies used rocks significantly more frequently than did ruffe, but their use of rock habitat decreased during dark conditions. Ruffe were found more often in plant habitats and less often near the wall of the pool in trials during daylight with concentrated food. Activity and habitat use of ruffe and round goby did not significantly differ between single and mixed species trials. Overall, we found little evidence for negative ecological interactions between ruffe and round goby in these laboratory experiments.

Savino, J. F.; Riley, S. C.; Holuszko, M. J.

2007-01-01

173

Effect of soil invertebrates on the formation of humic substances under laboratory conditions  

NASA Astrophysics Data System (ADS)

The complete polymerization of phenols and proteins (one of the processes involved in the formation of humic substances) was explained. It was shown that fly ( Bibio marci) larvae and earthworms ( Aporrectodea caliginosa) participate in the complete polymerization of phenols and proteins. In a laboratory experiment, invertebrates participated in the degradation of organic matter and the synthesis of humic substances, which was proved in experiments with 14C-labeled phenols and proteins. The same organic substances (phenols and proteins) without the impact of invertebrates were used as the control substances. The distributions of the 14C isotope in alkaline extracts separated by solubility in acids (humic and fulvic acids) was compared to those of the control substances. The portion of the 14C isotope in the humic acids in the excrements of Bibio marci was higher than that in the control substances. The content of 14C-labeled humic substances in the excrements of the earthworm Aporrectodea caliginosa exceeded the control values only in the experiment with proteins. When clay material was added to the organic substances, the portion of the 14C isotope in the humic acids increased in both experiments with phenols and proteins. When these substrates passed through the digestive tracts of the invertebrates, the polymerization of organic substances and the inclusion of proteins and phenols into humic acids occurred.

Frouz, J.; Li, X.; Brune, A.; Pizl, V.; Abakumov, E. V.

2011-08-01

174

Juvenile development of Callinectes danae Smith, 1869 (Crustacea, Decapoda, Brachyura, Portunidae) under laboratory conditions.  

PubMed

The juvenile development of Callinectes danae was investigated from megalopae obtained in neuston samples at Ubatuba, São Paulo, Brazil. The individuals were raised in the laboratory under constant temperature (25 ± 1°C), filtered sea water from the collection location (35‰), and natural photoperiod. Newly hatched Artemia sp. nauplii were offered as food on a daily basis and ornamental-fish food was also provided for the juveniles from the 4th stage on. Twelve stages of the juvenile phase were obtained. The main morphological features that allowed recognition of the first juvenile stage were drawn and described. All the subsequent stages obtained were examined and measured, and the main changes in relation to the first stage were recorded. Sexual dimorphism becomes apparent from the fourth juvenile stage onwards. Some appendages and morphological features proved to be of great importance in the identification of species, including the number of segments of the antennal flagellum and the number of setae on the maxilla and on the 1st, 2nd and 3rd maxillipeds. These can probably be used for future comparisons and species identifications. PMID:24676164

Bolla, Eduardo A; Fransozo, Vivian; Negreiros-Fransozo, Maria Lucia

2014-03-01

175

Estimating surface water risk at Oak Ridge National Laboratory: Effects of site conditions on modeling results  

SciTech Connect

Multiple source term and groundwater modeling runs were executed to estimate surface water {sup 90}Sr concentrations resulting from leaching of sludges in five 180,000 gallon Gunite{trademark} tanks at Oak Ridge National Laboratory. Four release scenarios were analyzed: (1) leaching of unstabilized sludge with immediate tank failure; (2) leaching of unstabilized sludge with delayed tank failure due to chemical degradation; (3) leaching of stabilized sludge with immediate tank failure; and (4) leaching of residual contamination out of the shells of empty tanks. Source terms and concentrations of {sup 90}Sr in the stream directly downgradient of the tanks were calculated under these release scenarios. The following conclusions were drawn from the results of the modeling: (1) small changes in soil path length resulted in relatively large changes in the modeled {sup 90}Sr concentrations in the stream; (2) there was a linear relationship between the amount of sludge remaining in a tank and the peak concentration of {sup 90}Sr in the stream; (3) there was a linear relationship between the cumulative {sup 90}Sr release from a tank and the peak concentration of {sup 90}Sr in the stream; (4) sludge stabilization resulted in significantly reduced peak concentrations of {sup 90}Sr in the stream; and (5) although radioactive decay of {sup 90}Sr during the period of tank degradation resulted in incrementally lower peak {sup 90}Sr concentrations in surface water than under the immediate tank failure scenarios these concentrations were equivalent under the two scenarios after about 90 years.

Curtis, A.H. III

1996-08-01

176

Interactions between Bacillus thuringiensis subsp. israelensis and Fathead Minnows, Pimephales promelas Rafinesque, under Laboratory Conditions  

PubMed Central

Interactions between Bacillus thuringiensis subsp. israelensis and fathead minnows, Pimephales promelas, were studied in laboratory exposures to two commercial formulations, Vectobac-G and Mosquito Attack. Mortality among fatheads exposed to 2.0 × 106 to 6.5 × 106 CFU/ml with both formulations was attributed to severe dissolved oxygen depletion due to formulation ingredients rather than to direct toxicity from the parasporal crystal. No adverse effects were observed at 6.4 × 105 CFU/ml and below. Fathead minnows rapidly accumulated high numbers of spores with 1 h of exposure to 2.2 × 105 CFU of Mosquito Attack per ml, producing whole-body counts of 4.0 × 106 CFU per fish. Comparison of counts on gastrointestinal tract samples and whole-body samples and high numbers of spores in feces indicated that ingestion was the major route of exposure. B. thuringiensis subsp. israelensis spore counts decreased rapidly after transfer of fish to clean water, with a drop of over 3 orders of magnitude in 1 day. Spores were rarely detected in fish after 8 days but were detectable in feces for over 2 weeks. These findings suggest that fish could influence the dissemination of B. thuringiensis subsp. israelensis, and possibly other microbial agents, in the aquatic environment. PMID:16348271

Snarski, Virginia M.

1990-01-01

177

Comparison of linuron degradation in the presence of pesticide mixtures in soil under laboratory conditions.  

PubMed

It is widely recognised that complex interactions occur between chemicals in mixtures. In many agricultural situations, the use of tank mixes and complex spray programs is a common practice. Insecticides, fungicides and a herbicide being applied in potato protection were used in this research. Interactions between linuron and insecticides, such as thiamethoxam or clothianidin, and fungicides, such as mancozeb or chlorothalonil, were examined in soil. The degradation rate of linuron in soil during laboratory incubation in six treatments was studied. Mixtures of linuron with mancozeb in sandy loam and clay loam soils had a significant effect on the persistence of this herbicide. For example, for the same herbicide, t 1/2 values for linuron were from 37 days in sandy loam to 44 days in clay loam. These values changed (64-67 days) when thiamethoxam and mancozeb were in soil. When mancozeb was added only, the half-life values were from 59 to 62 days, respectively. Other mixtures with chlorothalonil, thiamethoxam and clothianidin did not have any effect. In order to compare linuron degradation rates in soils, a single first-order model and expanded statistical analysis were used. PMID:23525775

Swarcewicz, Maria; Gregorczyk, Andrzej; Sobczak, Justyna

2013-10-01

178

Survivorship and fertility schedules of two Sumatran tortoise beetles, Aspidomorpha miliaris and A. sanctaecrucis (Coleoptera: Chrysomelidae) under laboratory conditions  

Microsoft Academic Search

Summary  Two species of tortoise beetles,Aspidomorpha miliaris (AM) andA. sanctaecrucis (AS) feeding on a shrub-like morning glory,Ipomoea carnea, were reared under laboratory conditions to study their survivorship and fertility schedules. AM and AS required 34–39 days\\u000a and 30–37, respectively, for the development of the immature stages. The mean longevity of the males was 88.4 days in AM and\\u000a 63.8 in AS,

Koji Nakamura; Idrus Abbas; Ahsol Hasyim

1989-01-01

179

Egg-to-fry survival of two strains of Atlantic salmon (Salmo salar) in stream incubators under laboratory conditions  

USGS Publications Warehouse

Egg-to-fry survival of two strains of Atlantic salmon (Salmo salar) was evaluated under laboratory conditions in two commercial stream egg incubators. The survival was also examined based on egg developmental stage (i.e., green eggs, eyed egggs, advanced eggs). There was no significant difference in survival of eggs in the Jordan-Scotty and Whitlock-Vibert incubators. However, the survival of Sebago strain Atlantic slamon eggs was significantly higher than that of Penobscot stream eggs, and survival increased with advanced egg developmental stage.

Johnson, James H.

2003-01-01

180

Bioremediation of endosulfan contaminated soil and water -- optimization of operating conditions in laboratory scale reactors.  

PubMed

A mixed bacterial culture consisted of Staphylococcus sp., Bacillus circulans-I and -II has been enriched from contaminated soil collected from the vicinity of an endosulfan processing industry. The degradation of endosulfan by mixed bacterial culture was studied in aerobic and facultative anaerobic conditions via batch experiments with an initial endosulfan concentration of 50mg/L. After 3 weeks of incubation, mixed bacterial culture was able to degrade 71.58+/-0.2% and 75.88+/-0.2% of endosulfan in aerobic and facultative anaerobic conditions, respectively. The addition of external carbon (dextrose) increased the endosulfan degradation in both the conditions. The optimal dextrose concentration and inoculum size was estimated as 1g/L and 75mg/L, respectively. The pH of the system has significant effect on endosulfan degradation. The degradation of alpha endosulfan was more compared to beta endosulfan in all the experiments. Endosulfan biodegradation in soil was evaluated by miniature and bench scale soil reactors. The soils used for the biodegradation experiments were identified as clayey soil (CL, lean clay with sand), red soil (GM, silty gravel with sand), sandy soil (SM, silty sand with gravel) and composted soil (PT, peat) as per ASTM (American society for testing and materials) standards. Endosulfan degradation efficiency in miniature soil reactors were in the order of sandy soil followed by red soil, composted soil and clayey soil in both aerobic and anaerobic conditions. In bench scale soil reactors, endosulfan degradation was observed more in the bottom layers. After 4 weeks, maximum endosulfan degradation efficiency of 95.48+/-0.17% was observed in red soil reactor where as in composted soil-I (moisture 38+/-1%) and composted soil-II (moisture 45+/-1%) it was 96.03+/-0.23% and 94.84+/-0.19%, respectively. The high moisture content in compost soil reactor-II increased the endosulfan concentration in the leachate. Known intermediate metabolites of endosulfan were absent in all the above degradation studies. PMID:16730891

Kumar, Mathava; Philip, Ligy

2006-08-21

181

Laboratory algal bioassays using PAM fluorometry: effects of test conditions on the determination of herbicide and field sample toxicity.  

PubMed

Pulse Amplitude Modulation (PAM) fluorometry, based on chlorophyll a fluorescence, is a frequently used technique in algal bioassays to assess toxicity of single compounds or complex field samples. Several test conditions can influence the test results, and because a standardized test protocol is currently lacking, linking the results of different studies is difficult. Therefore, the aim of the present study was to gain insight into the effects of test conditions of laboratory algal bioassays using PAM fluorometry on the outcome of toxicity tests. To this purpose, we described the results from several pilot studies on test development in which information is provided on the effects of the main test factors during the pretest phase, the test preparation, the exposure period, and the actual measurement. The experiments were focused on individual herbicides and complex field samples and included the effects of culturing conditions, cell density, solvent concentration, exposure time, and the presence of actinic light. Several of these test conditions were found to influence the outcome of the toxicity test, and the presented information provides important background information for the interpretation of toxicity results and describes which test conditions should be taken into account when using an algal bioassay with PAM fluorometry. Finally, the application of PAM fluorometry in algal toxicity testing is discussed. PMID:24478234

Sjollema, Sascha B; van Beusekom, Sebastiaan A M; van der Geest, Harm G; Booij, Petra; de Zwart, Dick; Vethaak, A Dick; Admiraal, Wim

2014-05-01

182

Rupture modes in laboratory earthquakes: Effect of fault prestress and nucleation conditions  

NASA Astrophysics Data System (ADS)

Seismic inversions show that earthquake risetimes may be much shorter than the overall rupture duration, indicating that earthquakes may propagate as self-healing, pulse-like ruptures. Several mechanisms for producing pulse-like ruptures have been proposed, including velocity-weakening friction, interaction of dynamic rupture with fault geometry and local heterogeneity, and effect of bimaterial contrast. We present experimental results on rupture mode selection in laboratory earthquakes occurring on frictional interfaces, which were prestressed both in compression and in shear. Our experiments demonstrate that pulse-like ruptures can exist in the absence of a bimaterial effect or of local heterogeneities. We find a systematic variation from crack-like to pulse-like rupture modes with both (1) decreasing nondimensional shear prestress and (2) decreasing absolute levels of shear and normal prestress for the same value of nondimensional shear prestress. Both pulse-like and crack-like ruptures can propagate with either sub-Rayleigh or supershear rupture speeds. Our experimental results are consistent with theories of ruptures on velocity-weakening interfaces, implying that velocity-weakening friction plays an important role in governing the dynamic behavior of earthquake ruptures. We show that there is no measurable fault-normal stress decrease on the fault plane due to the nucleation procedure employed in experiments, and hence, this is not a factor in the rupture mode selection. We find that pulse-like ruptures correspond to the levels of nondimensional shear prestress significantly lower than the static friction coefficient, suggesting that faults hosting pulse-like ruptures may operate at low levels of prestress compared to their static strength.

Lu, Xiao; Rosakis, Ares J.; Lapusta, Nadia

2010-12-01

183

Hydrologic conditions at the Idaho National Engineering Laboratory, 1982 to 1985  

USGS Publications Warehouse

Aqueous chemical and radioactive wastes discharged since 1952 to unlined ponds and wells at the INEL (Idaho National Engineering Laboratory) have affected water quality in perched groundwater zones and in the Snake River Plain Aquifer. Routine waste water disposal was changed from deep injection wells to ponds at the ICPP (Idaho Chemical Processing Plant) in 1984. During 1982-85, tritium concentrations increased in perched groundwater zones under disposal ponds, but cobalt-60 concentrations decreased. In 1985, perched groundwater under TRA disposal ponds contained up to 1,770 +or-30 pCi/mL (picocuries/milliliter) of tritium and 0.36+or-0.05 pCi/mL of cobalt-60. During 1982-85, tritium concentrations in water in the Snake River Plain aquifer decreased as much as 80 pCi/mL near the ICPP. In 1985, measurable tritium concentrations ranged from 0.9+or-0.3 to 93.4 +or-2.0 pCi/mL. Tritium was detected in groundwater near the southern boundary of the INEL, 9 miles south of the ICPP and TRA. Strontium-90 concentrations in groundwater, up to 63 +or-5 pCi/L (picocuries per liter) near the ICPP, generally were smaller than 1981 concentrations. Cesium-137 concentrations in groundwater near the ICPP ranged from 125 +or-14 to 237 +or-45 pCi/L. Maximum concentrations of plutonium-238 and plutonium-239 , -240 (undivided) were 1.31 +or-.0019 pCi/ml and 1.9 +or-0.00003 pCi/L. Sodium and chloride generally decreased during 1982-85. Nitrate concentrations increased near the TRA and NRF (Naval Reactors Facility) and decreased near the ICPP. (USGS)

Pittman, J.R.; Fischer, P.R.; Jensen, R.G.

1988-01-01

184

Persistence of four s-triazine herbicides in river, sea and groundwater samples exposed to sunlight and darkness under laboratory conditions.  

PubMed

The persistence of terbuthylazine, simazine, atrazine and prometryn (s-triazine herbicides) was studied in sea, river and groundwaters during long-term laboratory incubation (127 days) under different laboratory conditions (light-darkness at 20 degrees C). Analysis of herbicides was performed by GC-NPD and their identity was confirmed by GC-MSD. A micro on-line method for the isolation of herbicide residues was used. The results showed that light had little effect on the removal of the four herbicides in riverwater but had a marked effect on their removal from sea and groundwater. Surprisingly, this removal appeared to be inversely proportional to the concentration of dissolved organic materials. In general, the degradation order was similar in sea and riverwaters; simazine was the most readily degraded compound (t(1/2)= 29-49 days), while terbuthylazine was the most persistent with the longest half-lives (76-331 days). In groundwater, terbuthylazine also showed greater persistence but prometryn was the compound with a fastest degradation rate, half-lives ranged from 88 days for prometryn to approximately 100 days for the other three compounds in light conditions and 263-366 days for prometryn and terbuthylazine, respectively, in darkness. Only for terbuthylazine was the remaining percentage at the end of the experiment higher than 50% under light conditions in riverwater, while in the other cases, the remaining percentage varied from 7 to 43% for simazine in seawater and atrazine in groundwater, respectively. Finally, a greater persistence was observed in groundwater for the four compounds. PMID:15262160

Navarro, Simón; Vela, Nuria; Giménez, M José; Navarro, Ginés

2004-08-15

185

Vegetation-derived cues for the selection of oviposition substrates by Anopheles albimanus under laboratory conditions.  

PubMed

Oviposition response of gravid Anopheles albimanus Wiedemman (Diptera: Culicidae) females to water containing Brachiaria mutica, Cynodon dactylon, Jouvea straminea, Fimbristylis spadicea, and Ceratophyllum demersum was investigated. Gravid An. albimanus females deposited similar egg numbers in cups containing natural plants in water from natural breeding sites and in cups containing natural plants in distilled water. Gravid mosquitoes deposited significantly more eggs in cups containing natural plants in water from natural breeding sites than in cups containing artificial plants in water from the corresponding natural breeding sites. These results were confirmed in experiments conducted in a wind tunnel, indicating that female response is mediated by chemical cues from plants. Bioassays with organic extracts of all 5 plant species indicated that these extracts at 100%, 10%, and 1% concentrations had an oviposition repellent effect, while attractiveness was observed at 0.1%, 0.01%, and 0.001%. Gas chromatography and mass spectrometry analysis of the organic extracts found in all 5 plants showed a mixture of terpenoid and alcohol compounds, among them: guaiacol, phenol, isoeugenol, longifolene, caryophyllene, phenyl ethyl alcohol, and p-cresol. These results suggest that middle-range volatiles from plants may function as chemical cues for the female's oviposition response in this mosquito species. PMID:16506557

Torres-Estrada, José Luis; Meza-Alvarez, R Amanda; Cibrián-Tovar, Juan; Rodríguez-López, Mario H; Arredondo-Jiménez, Juan I; Cruz-López, Leopoldo; Rojas-Leon, Julio C

2005-12-01

186

Effect of some diets on Macrolophus pygmaeus rambur (Hemiptera: Miridae) fitness under laboratory conditions.  

PubMed

Fitness parameters of omnivore predatory bug Macrolophus pygmaeus were studied on various diets consisting of green peach aphid Myzus persicae + eggplant leaf disc, eggs of Ephestia kuehniella + eggplant leafdisc, pollen + eggplant leaf disc, eggs of E. kuehniella + pollen + eggplant leaf disc. The experiments were began from 1- day nymphs until 32-day adults. The tests were done at 25 degress C, 65+/-5% RH, 16L: 8D h photoperiod. The results showed that adding floral material to the animal prey (eggs of E. kuehniella) containing treatment shortened the nymphal development time. The highest rate of mortality of M. pygmaeus nymphs was observed on pollen + eggplant leaf disc. The sex ratio of emerged adults was similar between treatments. The preoviposition period was the same in a ll treatments. T he fecundity of M . pygmaeuswas affected by feeding diets. Females fed on eggs of E. kuehniella + pollen + eggplant leaf disc have highest rate of fecundity. Based on results, diet of E. kuehniella eggs + pollen + eggplant leaf disc is the most suitable diet for rearing of this predatory insect. Obtained results somehow were expectable due to the high nitrogen extent, vitamins and mineral materials found in the pollen. PMID:17385505

Maleki, F; Ashouri, A; Mohaghegh, J; Bandani, A R

2006-01-01

187

[Pathogenic effect of 3 parasitic nematodes in Aedes aegypti larvae under laboratory conditions in Cuba].  

PubMed

The pathogenic effect of three parasitic nematodes, Romanomermis culicivorax Ross y Smith, 1976, Romanomermis iyengari Welch, 1964, and Strelkovimermis spiculatus Poinar and Camino, 1986, was evaluated at different application doses in larvae of Aedes aegypti. For each experimental unit, one hundred second instar larvae of this mosquitoe were infested with preparasites of the three nematode species in the following proportions: 3:1, 5:1, 10:1, 15:1 and 20:1. Both infestation mean and parasitism rate increased as the doses augmented. Romanomermis culicivorax proved to be more effective at low doses when compared to other species; however, with the 10:1 proportion, all the nematodes caused 100% of mortality. S. spiculatus showed the highest infestation rate. For this reason, a proportion of 10:1 could be recommended to evaluate these nematodes under natural conditions in useless artificial containers as a biological alternative for Aedes aegypti control. PMID:17969278

Rodríguez Rodríguez, Jinnay; García García, Israel; Menéndez, Zulema; García Avila, Israel; Eladio Sánchez, Jesús; Pérez Pacheco, Rafael

2005-01-01

188

Optimal conditions for high current proton irradiations at the university of Wisconsin's ion beam laboratory  

NASA Astrophysics Data System (ADS)

The National Electrostatics Corporation's (NEC) Toroidal Volume Ion Source (TORVIS) source is known for exceptionally high proton currents with minimal service downtime as compared to traditional sputter sources. It has been possible to obtain over 150?A of proton current from the source, with over 70?A on the target stage. However, beam fluxes above ~1×1017/m2-s may have many undesirable effects, especially for insulators. This may include high temperature gradients at the surface, sputtering, surface discharge, cracking or even disintegration of the sample. A series of experiments were conducted to examine the role of high current fluxes in a suite of ceramics and insulating materials. Results will show the optimal proton irradiation conditions and target mounting strategies needed to minimize unwanted macro-scale damage, while developing a procedure for conducting preliminary radiation experiments.

Wetteland, C. J.; Field, K. G.; Eiden, T. J.; Gerczak, T. J.; Maier, B. R.; Albakri, O.; Sridharan, K.; Allen, T. R.

2013-04-01

189

Bacillus thuringiensis var. tenebrionis control of synanthropic mites (Acari: Acaridida) under laboratory conditions.  

PubMed

Bacillus thuringiensis (Bt) toxins present a potential for control of pest mites. Information concerning the effect of Bt and its possible application to the biocontrol of synathropic mites is rare. The toxic effect of Bacillus thuringiensis var. tenebrionis producing Cry3A toxin was tested on the mites Acarus siro L., Tyrophagus putrescentiae (Schrank), Dermatophagoides farinae Hughes, and Lepidoglyphus destructor (Schrank) via feeding tests. Fifty mites were reared on Bt additive diets in concentrations that ranged from 0 to 100 mg g(-1) under optimal conditions for their development. After 21 days, the mites were counted and the final populations were analyzed using a polynomial regression model. The Bt diet suppressed population growth of the four mite species. The fitted doses of Bt for 50% suppression of population growth were diets ranging from 25 to 38 mg g(-1). There were no remarkable differences among species. Possible applications of Bt for the control of synanthropic mites are discussed. PMID:19381844

Erban, Tomas; Nesvorna, Marta; Erbanova, Michaela; Hubert, Jan

2009-12-01

190

Aggressive interactions between Solenopsis invicta and Linepithema humile (Hymenoptera: Formicidae) under laboratory conditions.  

PubMed

The Argentine ant, Linepithema humile (Mayr), and the red imported fire ant, Solenopsis invicta Buren, are natural agonists in their country of origin. Since the first report of L. humile in California in 1907 its range expanded statewide, displacing native ant species wherever it spread. Since the discovery of established populations of S. invicta in southern California in 1998, it has been restricted to discrete areas of southern California. However, as these discrete populations expand, they are encountering large populations of L. humile, which are effective competitors for available resources and are particularly aggressive in their encounters with other ant species such as S. invicta. Most Dolichoderine ants such as L. humile do not prefer to forage on baits made with defatted corn grit and soybean oil typically used in red imported fire ant control programs. Applications of these baits in areas where distributions of these species overlap might selectively affect populations of S. invicta and give L. humile a competitive advantage. Three laboratory experiments were conducted to determine the competitive outcomes between S. invicta pitted against L. humile: 1) agonistic behavior of workers in small arenas, 2) colony interactions with different population ratios, and 3) the effects of pyriproxyfen on the competitiveness of S. invicta against L. humile. Populations of S. invicta consisting of major workers killed more L. humile than did minors or a mixture of majors and minors. When paired against L. humile colonies consisting of 1,100 workers, colonies consisting of 38 S. invicta workers were easily defeated by L. humile. Colonies consisting of 450 S. invicta workers plugged their nest entrances, but they were ultimately defeated by L. humile after 13 d. The S. invicta colonies consisting of 1,100 workers took control of the bridge connecting the colonies, invaded the L. humile colony, killed the Argentine ant queens, and removed their brood. Pyriproxyfen-treated fire ant workers took significantly longer to chase the Argentine ants from a connecting bridge than did untreated fire ants. Thus, fire ant baits may have long-term effects on intercolonial aggression between S. invicta and L. humile, especially when Argentine ant populations are high in the summer. PMID:17370822

Kabashima, J N; Greenberg, L; Rust, M K; Paine, T D

2007-02-01

191

Uptake of cadmium by the invasive perennial weeds Ranunculus repens and Geranium robertianum under laboratory conditions.  

PubMed

The objective of this study was to compare the accumulation and partitioning of cadmium (Cd) in a fibrous versus a tap root weed, Ranunculus repens and Geranium robertianum respectively. To meet this objective, we compared the accumulation by and the partitioning of Cd in R repens versus G. robertianum grown in soils spiked with 0.015 grams of Cd for a period of three weeks. The rate of Cd uptake was also compared by following the fate of 109Cd within the root, stem and leaf of the two weeds. Prior to Cd exposure, leaf and stem of control R. repens contained significantly greater amounts of Cd as compared to G. robertianum, whereas Cd concentrations in roots of the control plants for the two species were not significantly different (p > 0.05, student's t-test). Post Cd exposure the two species contained similar amounts of Cd in leaf and stem, however, roots of R. repens contained almost two-fold the amounts of Cd as compared to G. robertianum. Comparison of k (h(-1), rate of 109Cd uptake) for stem, leaf and root of the two species indicated that G. robertianum accumulated 109Cd over the first 24-48 h at a faster rate as compared to R. repens. For both species and all three organs, maximum accumulation of 109Cd occurred within the first 24-48 h. Our findings indicate that the fate of Cd within these two species is quite different with the fibrous root of R. repens serving to accumulate and store Cd whereas in G. robertianum, Cd is rapidly taken up and tends to be accumulated within its leaf. PMID:12094937

O'Keeffe, Juliette; Bendell-Young, L I

2002-06-01

192

Copper-binding proteins in liver of bluegills exposed to increased soluble copper under field and laboratory conditions.  

PubMed Central

Livers from bluegills exposed to increased soluble copper (Cu) under field and laboratory conditions were analyzed to determine the concentration and distribution of Cu in metalloproteins of different molecular size. Analyses were performed on bluegills collected from the impoundment of the H. B. Robinson Steam Electric Plant (Florence, SC) near the effluent discharge from the power plant, near the water intake to the cooling system, and from a control pond as well as on bluegills exposed under controlled laboratory conditions. Metalloproteins were separated into low molecular weight (LMW), intermediate molecular weight (IMW), and high molecular weight (HMW) fractions by using high-performance liquid chromatography. In the field-exposed bluegills, Cu concentrations in the LMW, IMW, and HMW fractions were highest in bluegills from the discharge site and lowest in those from the control pond. In the laboratory-exposed bluegills, Cu concentrations in the fractions increased with exposure concentration and time. Concentrations of Cu in the LMW protein fraction and pellet of bluegills exposed to 160 micrograms Cu/L appeared to plateau with long exposure times, whereas those in the HMW fraction continued to increase. Bluegills maintained in 80 micrograms Cu/L water at pH 5.5 accumulated lower concentrations of Cu in the LMW and pellet fractions and higher amounts in the HMW than in those maintained in 80 micrograms Cu/L at pH 7.0. Mortality was dependent on exposure concentration and duration and was higher in bluegills maintained in water at pH 5.5 than at pH 7.0. PMID:3709431

Harrison, F L; Lam, J R

1986-01-01

193

Laboratory investigation of oil-suspended particulate matter aggregation under different mixing conditions.  

PubMed

Oil-suspended particulate matter aggregation (OSA) has been recognized by the oil spill remediation community to effectively enhance the cleansing of spilled oil in the marine environment. While studies have investigated the application of mineral fines as an effective method to facilitate oil dispersion, decision-makers still lack information on the role of mixing energy in OSA formation and its significance to oil dispersion in real spills. This work studied the effect of level and duration of mixing energy on OSA formation using the standard reference material 1,941 b and Arabian light crude oil. The results showed that dispersed small oil droplets increased with an increase of both the level and duration of mixing energy to form multi-droplet OSAs. The sizes of the dispersed droplets varied between 5 and 10 ?m under different conditions studied. The maximum oil trapping efficiency increased from 23% to 33%, the oil to sediment ratio increased from 0.30 to 0.43 g oil/g sediment, and the required shaking time decreased from 2.3 to 1.1h as the shaking rate increased from 2.0 to 2.3 Hz. Based on the size measurement results, a breakage effect on the formed OSAs and sediment flocs was confirmed under high mixing energy level. PMID:24462999

Sun, Juan; Khelifa, Ali; Zhao, Chaocheng; Zhao, Dongfeng; Wang, Zhendi

2014-03-01

194

Heterogeneous ice nucleation activity of bacteria: new laboratory experiments at simulated cloud conditions  

NASA Astrophysics Data System (ADS)

The ice nucleation activities of five different Pseudomonas syringae, Pseudomonas viridiflava and Erwinia herbicola bacterial species and of Snomax™ were investigated in the temperature range between -5 and -15°C. Water suspensions of these bacteria were directly sprayed into the cloud chamber of the AIDA facility of Forschungszentrum Karlsruhe at a temperature of -5.7°C. At this temperature, about 1% of the Snomax™ cells induced immersion freezing of the spray droplets before the droplets evaporated in the cloud chamber. The living cells didn't induce any detectable immersion freezing in the spray droplets at -5.7°C. After evaporation of the spray droplets the bacterial cells remained as aerosol particles in the cloud chamber and were exposed to typical cloud formation conditions in experiments with expansion cooling to about -11°C. During these experiments, the bacterial cells first acted as cloud condensation nuclei to form cloud droplets. Then, only a minor fraction of the cells acted as heterogeneous ice nuclei either in the condensation or the immersion mode. The results indicate that the bacteria investigated in the present study are mainly ice active in the temperature range between -7 and -11°C with an ice nucleation (IN) active fraction of the order of 10-4. In agreement to previous literature results, the ice nucleation efficiency of Snomax™ cells was much larger with an IN active fraction of 0.2 at temperatures around -8°C.

Möhler, O.; Georgakopoulos, D. G.; Morris, C. E.; Benz, S.; Ebert, V.; Hunsmann, S.; Saathoff, H.; Schnaiter, M.; Wagner, R.

2008-10-01

195

Heterogeneous ice nucleation activity of bacteria: new laboratory experiments at simulated cloud conditions  

NASA Astrophysics Data System (ADS)

The ice nucleation activities of five different Pseudomonas syringae, Pseudomonas viridiflava and Erwinia herbicola bacterial species and of SnomaxTM were investigated in the temperature range between -5 and -15°C. Water suspensions of these bacteria were directly spray into the cloud chamber of the AIDA facility of Forschungszentrum Karlsruhe at a temperature of -5.7°. At this temperature, about 1% of the SnomaxTM cells induced freezing of the spray droplets before they evaporated in the cloud chamber. The other suspensions of living cells didn't induce any measurable ice concentration during spray formation at -5.7°. The remaining aerosol was exposed to typical cloud activation conditions in subsequent experiments with expansion cooling to about -11°C. During these experiments, the bacterial cells first acted as cloud condensation nuclei to form cloud droplets and then eventually acted as ice nuclei to freeze the droplets. The results indicate that the bacteria investigated in the present study are mainly ice active in the temperature range between -7 and -11°C with an INA fraction of the order of 10-4. The ice nucleation efficiency of SnomaxTM cells was much larger with an INA fraction of 0.2 at temperatures around -8°C.

Möhler, O.; Georgakopoulos, D. G.; Morris, C. E.; Benz, S.; Ebert, V.; Hunsmann, S.; Saathoff, H.; Schnaiter, M.; Wagner, R.

2008-04-01

196

Kinematic Self-Similarity  

E-print Network

Self-similarity in general relativity is briefly reviewed and the differences between self-similarity of the first kind and generalized self-similarity are discussed. The covariant notion of a kinematic self-similarity in the context of relativistic fluid mechanics is defined. Various mathematical and physical properties of spacetimes admitting a kinematic self-similarity are discussed. The governing equations for perfect fluid cosmological models are introduced and a set of integrability conditions for the existence of a proper kinematic self-similarity in these models is derived. Exact solutions of the irrotational perfect fluid Einstein field equations admitting a kinematic self-similarity are then sought in a number of special cases, and it is found that; (1) in the geodesic case the 3-spaces orthogonal to the fluid velocity vector are necessarily Ricci-flat and (ii) in the further specialisation to dust the differential equation governing the expansion can be completely integrated and the asymptotic properties of these solutions can be determined, (iii) the solutions in the case of zero-expansion consist of a class of shear-free and static models and a class of stiff perfect fluid (and non-static) models, and (iv) solutions in which the kinematic self-similar vector is parallel to the fluid velocity vector are necessarily Friedmann-Robertson-Walker (FRW) models.

A. A. Coley

1996-10-25

197

Laboratory Test Methods to Determine the Degradation of Plastics in Marine Environmental Conditions  

PubMed Central

In this technology report, three test methods were developed to characterize the degradation of plastic in marine environment. The aim was to outline a test methodology to measure the physical and biological degradation in different habitats where plastic waste can deposit when littered in the sea. Previously, research has focused mainly on the conditions encountered by plastic items when floating in the sea water (pelagic domain). However, this is just one of the possible habitats that plastic waste can be exposed to. Waves and tides tend to wash up plastic waste on the shoreline, which is also a relevant habitat to be studied. Therefore, the degradation of plastic items buried under sand kept wet with sea water has been followed by verifying the disintegration (visual disappearing) as a simulation of the tidal zone. Most biodegradable plastics have higher densities than water and also as a consequence of fouling, they tend to sink and lay on the sea floor. Therefore, the fate of plastic items lying on the sediment has been followed by monitoring the oxygen consumption (biodegradation). Also the effect of a prolonged exposure to the sea water, to simulate the pelagic domain, has been tested by measuring the decay of mechanical properties. The test material (Mater-Bi) was shown to degrade (total disintegration achieved in less than 9?months) when buried in wet sand (simulation test of the tidal zone), to lose mechanical properties but still maintain integrity (tensile strength at break?=??66% in 2?years) when exposed to sea water in an aquarium (simulation of pelagic domain), and substantially biodegrade (69% in 236?days; biodegradation relative to paper: 88%) when located at the sediment/sea water interface (simulation of benthic domain). This study is not conclusive as the methodological approach must be completed by also determining degradation occurring in the supralittoral zone, on the deep sea floor, and in the anoxic sediment. PMID:22737147

Tosin, Maurizio; Weber, Miriam; Siotto, Michela; Lott, Christian; Degli Innocenti, Francesco

2012-01-01

198

Comparative Studies on the Ecophysiological Differences of Two Green Tide Macroalgae under Controlled Laboratory Conditions  

PubMed Central

Yellow Sea green tides have occurred in coastal China almost every year from 2007 to 2011. Ulva prolifera (Müller) J. Agardh has been identified as the causative macroalgal species. U. intestinalis, however, has been observed in the bloom areas, co-occurring with U. prolifera, but it has not been found to be causative. The Yellow Sea green tide has shown consistent phases of development that match corresponding environmental changes. U. prolifera, not U. intestinalis, is dominant. Our experimental design was based on these observed phenomena, and the results of our field investigation indicated a close relationship between changes in principal environmental factors (irradiance, temperature, and salinity) and the development of each phase of the bloom. These main environmental factors were simulated to allow estimation and comparison of the physiological responses of U. prolifera and U. intestinalis. Ecophysiological differences were found between these two species. (1) More photosynthetic activity and plasticity were detected in U. prolifera. (2) U. prolifera was found to be more sensitive to dynamic environments, especially harsh and changing environmental conditions. U. intestinalis was found to be more stable, probably due to the higher stress tolerance given by its antioxidant system. (3) Markedly higher nutrient absorption activity was observed in U. prolifera. Comparisons of the ecophysiological traits of these two species in this present study may foster understanding of their natural ecological processes. Specifically, U. prolifera seemed to be more engaged with the ephemeral blooms, while U. intestinalis seemed to be directed toward persistence. This also suggests that the ecological success of U. prolifera may be inextricably linked to its higher capacity for photosynthesis, nutrient absorption, and nutrient assimilation. PMID:22905087

Wang, Ying; Wang, You; Zhu, Lin; Zhou, Bin; Tang, Xuexi

2012-01-01

199

Investigation on some biological aspects of Chrysoperla lucasina (Chrysopidae: Neuroptera) on Bemisia tabaci in laboratory conditions.  

PubMed

Bemisia tabaci is one of the most important key pests of many types of cultivated plants. Lacewings (Chrysopidae: Neuroptera) are predatory insects, widely used in biological control programs. Between them green lacewing is a promising biological control agent of pests in green houses and crop fields. In this study, gravid females of the green lacewing Chrysoperla lucasina (Lacroix) were captured from Sarepolzahab ( altitude 540m, latitude 34 degrees ,14' N 46 degrees, 9' E) in western part of Iran. Collected insects were reared in a growth chamber, under experimental conditions (25 +/- 1 degrees C, 70 +/- 5% RH and a photoperiod of 16:8 L: D). Different diets were offered to larvae which consisted of a whitefly species B. tabaci, an aphid Myzus persica and also lyophilized powder of drone honeybee (Apis melifera). As different foods were used to nurish larvae, so for each diet, mean larval period were calculated, and finally means were compared to each other. Anova in MSTAT-C was used for analysis of variance, and Duncan multiple range test (DMRT) to compare between means. The results showed that larvae had maximum duration of 27 +/- 0.33 days when fed on honeybee lyophilized powder and the minimum value was 17.9 +/- 0.3 days for B. tabaci. 25 +/- 0.27 day recorded for M. persicae. Food preference of the 3rd instar larvae of green lacewing was surveyed, they showed a food preference to M. persicae, to compare with B. tabaci, as the former has a bigger body size, so more easily to be captured by the predator larvae. The 3rd instar larvae of lacewing were more voracious on preys, than the 1st or the 2nd instar larvae. Statistically speaking, there were a significantly difference when mean of different preys consumed by predator larvae were compared. We found, that when the predator larvae have fed on B. tabaci, their development time was shorter, and when arrived to adult stage, the adults showed, an improved fertility. The results indicated that the suitable prey not only can increase the rate of through accelerating developmental stages of the predator and by means of an increase in its pupal body weight consequently promoting the fecundity of resulting adults, but also can alter predators population density in relation to own production numbers. PMID:23885430

Baghdadi, A; Sharifi, F; Mirmoayedi, A

2012-01-01

200

[Myocardial electrogenesis in laboratory rats under conditions of acute nitrite intoxication].  

PubMed

In anesthetized male rats the arterial blood pressure in femoral artery and electrocardiogram in standard leads were recorded uninterruptedly for 1-1.5 h under conditions of acute nitrite intoxication produced by a subcutaneous injection of water solution of sodium nitrite (donor of nitric oxide) at concentrations of 10, 30, and 50 mg/kg body mass. Results of the study have shown dose-dependent changes of arterial pressure as well as of time and amplitude characteristics of electrocardiogram under effect of NaNO2. At the threshold hypoxic dose, an increase of amplitude of R and S waves was observed by the 30-45th min, while at the maximal NaNO2 dose, amplitude of all waves rose by the 15th min of intoxication. High nitric doses often caused an increase of the ST segment above the isoelectric line and a rise of the amplitude of the T wave, on which a notch appeared in some cases. The change of the ECG time parameters was expressed in the dose-dependent development of bradycardia for the first 4-7 min; its level correlated with the progressively decreasing arterial pressure in the beginning (the 2-4th min) of nitrite intoxication. Variation analysis of heart rate spectral characteristics by Baevskii has revealed a rise of the total spectral power of pulse oscillations. Under effect of nitrite, in the spectrum of cardiointervals, quent recovery of the normal ECG spectrum in the end of the experimental period. The maximal nitrite dose produced more pronounced shifts of the heart rate spectrum towards the LF and VLF diapasons that were not restored for 1 h of experiment. Transitory processes of readjustment of the cardiac rhythm had discrete character. The nitrite dose of 50 mg/kg body mass increased the RR-interval after 4-7 min with amplitude steps of 3-5 imp/s and the time constant of 20-40 s. The revealed ECG changes had the reflex (enhancement of parasympathetic tonus) and metabolic (the hypoxic and histotoxic damage of myocardium) nature. PMID:20432710

Shumilova, T E; Shereshkov, V I; Ianvareva, I N; Nozdrachev, A D

2010-01-01

201

40 CFR Appendix G to Subpart A of... - UNEP Recommendations for Conditions Applied to Exemption for Essential Laboratory and Analytical...  

...Exemption for Essential Laboratory and Analytical Uses...of Environment ENVIRONMENTAL PROTECTION AGENCY...Exemption for Essential Laboratory and Analytical Uses...under the global laboratory exemption: a. Testing of oil and...

2014-07-01

202

In situ Analysis of Organic Matter in Martian Soil: Laboratory Measurements Under Martian Operating Conditions Supporting Treatment and Interpretation of SAM GC-MS Data  

NASA Astrophysics Data System (ADS)

This work presents laboratory measurements under martian operating conditions in comparison with the SAM GC-MS data provided by the Curiosity rover. Their treatment and interpretation supports the in situ analysis of organic matter on Mars.

Millan, M.; Szopa, C.; Coll, P.; Buch, A.; Cabane, M.; Coscia, D.; Glavin, D. P.; Freissinet, C.

2014-07-01

203

Exploring correlation between redox potential and other edaphic factors in field and laboratory conditions in relation to methane efflux.  

PubMed

Methane is primarily a biogenic gas, which is implicated in global warming. Although its production in the anoxic conditions is regulated by several edaphic factors, aquatic macrophytes also influence methane emission by providing aerenchyma to act as chimney for CH4 transport from the sediment to troposphere, by releasing root exudates to the sediment to serve as substrate for methanogenic bacteria and by transporting atmospheric O2 to rhizosphere, which stimulates CH4 consumption. Among the edaphic factors, redox potential (Eh) is the most important, which largely determines the action of methanogenic bacteria. Hence, a study was undertaken first to find out the correlation between CH4 emission and edaphic factors in the field conditions and then to understand the relationship between Eh and other edaphic factors. The field studies revealed that natural wetlands were the major source of CH4 emission, and the vegetation plays an important role in CH4 emission from the water bodies. However, it was very difficult to establish a strong relationship between the CH4 emission and the edaphic factors in the field conditions due to other limiting factors and their constant fluctuations. In this connection, the laboratory experiments exhibited that soil temperature, pH, moisture regime and incubation period were negatively correlated with Eh, which determines the initiation of methanogenic process. However, organic carbon and the water regime over the soil surface did not show any impact on Eh in this study. PMID:11686637

Singh, S N

2001-10-01

204

Two initial vaccinations with the Bm86-based Gavacplus vaccine against Rhipicephalus (Boophilus) microplus induce similar reproductive suppression to three initial vaccinations under production conditions  

PubMed Central

Background The cattle tick, Rhipicephalus (Boophilus) microplus, affects livestock production in many regions of the world. Up to now, the widespread use of chemical acaricides has led to the selection of acaricide-resistant ticks and to environmental contamination. Gavacplus is a subunit vaccine based on the recombinant Bm86 tick antigen expressed in yeast, capable to control infestations of R. microplus under controlled and production conditions. The vaccine constitutes the core element of broad control programs against this ectoparasite, in which acquired immunity in cattle to Bm86 is combined with a rational use of acaricides. At present, the conventional vaccine scheme consists of three doses that should be administered at weeks 0, 4 and 7, followed by a booster every six months. Results In this study we assayed a reduction in the number of the initial doses of Gavacplus, evaluated the time course and the level of bovine anti-Bm86 antibodies elicited, and analyzed the vaccine effect on ticks engorging on immunized cattle under production conditions. Following three different immunization schemes, the bovines developed a strong and specific immune response characterized by elevated anti-Bm86 IgG titers. A reduction in the weight of engorging female ticks, in the weight of the eggs laid and also in R. microplus viable eggs percentage was obtained by using only two doses of Gavacplus administered at weeks 0 and 4, followed by a booster six months later. This reduction did not differ from the results obtained on ticks engorging on cattle immunized at weeks 0, 4 and 7. It was also demonstrated that anti-Bm86 antibody titers over 1:640, measured in bovines immunized at weeks 0 and 4, were sufficient to affect weight and reproductive potential of female ticks as compared with ticks engorging on unvaccinated animals. In addition, no statistically significant differences were detected in the average weight of eggs laid by ticks engorged on immunized cattle that showed anti-Bm86 specific titers in the range of 1:640 to 1:81920. Conclusion The administration of two initial doses of Gavacplus containing 100 ?g of Bm86 antigen to non-immunized cattle under production conditions is sufficient to affect the weight and the reproductive capacity of R. microplus engorging females. According to these results, cattle herds' manipulation and vaccine costs could be potentially reduced with a positive impact on the implementation of integrated control programs against R. microplus. PMID:20846415

2010-01-01

205

Wave operators, similarity and dynamics for a class of Schroedinger operators with generic non-mixed interface conditions in 1D  

E-print Network

We consider a simple modification of the 1D-Laplacian where non-mixed interface conditions occur at the boundaries of a finite interval. It has recently been shown that Schr\\"odinger operators having this form allow a new approach to the transverse quantum transport through resonant heterostructures. In this perspective, it is important to control the deformations effects introduced on the spectrum and on the time propagator by this class of non-selfadjont perturbations. In order to obtain uniform-in-time estimates of the perturbed semigroup, our strategy consists in constructing stationary waves operators allowing to intertwine the modified non-selfadjoint Schr\\"odinger operator with a 'physical' Hamiltonian. For small values of a deformation parameter '{\\theta}', this yields a dynamical comparison between the two models showing that the distance between the corresponding semigroups is dominated by |{\\theta}| uniformly in time in the L^2-operator norm.

Andrea Mantile

2012-10-24

206

Wave operators, similarity and dynamics for a class of Schrödinger operators with generic non-mixed interface conditions in 1D  

SciTech Connect

We consider a simple modification of the 1D-Laplacian where non-mixed interface conditions occur at the boundaries of a finite interval. It has recently been shown that Schrödinger operators having this form allow a new approach to the transverse quantum transport through resonant heterostructures. In this perspective, it is important to control the deformations effects introduced on the spectrum and on the time propagator by this class of non-selfadjoint perturbations. In order to obtain uniform-in-time estimates of the perturbed semigroup, our strategy consists in constructing stationary wave operators allowing to intertwine the modified non-selfadjoint Schrödinger operator with a “physical” Hamiltonian. For small values of a deformation parameter “?,” this yields a dynamical comparison between the two models showing that the distance between the corresponding semigroups is dominated by ??? uniformly in time in the L{sup 2}-operator norm.

Mantile, Andrea [Laboratoire de Mathématiques, Université de Reims - FR3399 CNRS, Moulin de la Housse BP 1039, 51687 Reims (France)] [Laboratoire de Mathématiques, Université de Reims - FR3399 CNRS, Moulin de la Housse BP 1039, 51687 Reims (France)

2013-08-15

207

Influence of the redox condition dynamics on the removal efficiency of a laboratory-scale constructed wetland.  

PubMed

A laboratory reactor planted with Juncus effusus treating an artificial wastewater was used to investigate the short-term and long-term variations and interactions in the redox conditions as well as the removal efficiency of C and the N turnover. The permanent circulation of the process water enabled the micro-gradient processes to be evaluated for an operating period of 20 months. Steady-state conditions were achieved throughout the operating period with high mean removal efficiencies of 92.7% total organic carbon, 82.0% ammonia and 97.6% nitrate. Daily variations in the redox state of the rhizosphere of a few hundred mV were observed, ranging from about -200 to oxidized conditions of about +200 mV and driven by daylight. Variations in pH associated with changes in light and redox were linked to the dynamics of the fates of organic and inorganic carbon species. The ammonia removal processes were found to be firmly established, including for moderately reduced redox conditions with high efficiencies for E(h)>-50 mV. The enrichment of ammonia (up to 13 mg l(-1)) closely linked to the light, particularly during summertime, indicates the existence of hitherto unconsidered additional N turnover pathways in the rhizoplane involving N(2) produced by microbes or released by plants. C turnover was strongly related to the seasonal variation in illumination with minimum efficiencies during the dark season. In addition, it was characterized by oscillation with periods of approximately 1 month. The relationships found are dominant for biofilms on the rhizoplane and decisive for the removal efficiency of especially simple constructed and natural wetlands. The results highlight the importance of helophytes and their physiological specifics for removal processes. PMID:15607183

Wiessner, A; Kappelmeyer, U; Kuschk, P; Kästner, M

2005-01-01

208

Dynamic similarity in erosional processes  

USGS Publications Warehouse

A study is made of the dynamic similarity conditions obtaining in a variety of erosional processes. The pertinent equations for each type of process are written in dimensionless form; the similarity conditions can then easily be deduced. The processes treated are: raindrop action, slope evolution and river erosion. ?? 1963 Istituto Geofisico Italiano.

Scheidegger, A.E.

1963-01-01

209

40 CFR Appendix G to Subpart A of... - UNEP Recommendations for Conditions Applied to Exemption for Essential Laboratory and Analytical...  

Code of Federal Regulations, 2010 CFR

...and grease and total petroleum hydrocarbons in water; b. Testing of tar in road-paving materials; and c. Forensic finger printing. Production for essential laboratory and analytical purposes is authorized provided that these laboratory and...

2010-07-01

210

In search of water vapor on Jupiter: Laboratory measurements of the microwave properties of water vapor under simulated jovian conditions  

NASA Astrophysics Data System (ADS)

Detection and measurement of atmospheric water vapor in the deep jovian atmosphere using microwave radiometry has been discussed extensively by Janssen et al. (Janssen, M.A., Hofstadter, M.D., Gulkis, S., Ingersoll, A.P., Allison, M., Bolton, S.J., Levin, S.M., Kamp, L.W. [2005]. Icarus 173 (2), 447-453.) and de Pater et al. (de Pater, I., Deboer, D., Marley, M., Freedman, R., Young, R. [2005]. Icarus 173 (2), 425-447). The NASA Juno mission will include a six-channel microwave radiometer system (MWR) operating in the 1.3-50 cm wavelength range in order to retrieve water vapor abundances from the microwave signature of Jupiter (see, e.g., Matousek, S. [2005]. The Juno new frontiers mission. Tech. Rep. IAC-05-A3.2.A.04, California Institute of Technology). In order to accurately interpret data from such observations, nearly 2000 laboratory measurements of the microwave opacity of H2O vapor in a H2/He atmosphere have been conducted in the 5-21 cm wavelength range (1.4-6 GHz) at pressures from 30 mbars to 101 bars and at temperatures from 330 to 525 K. The mole fraction of H2O (at maximum pressure) ranged from 0.19% to 3.6% with some additional measurements of pure H2O. These results have enabled development of the first model for the opacity of gaseous H2O in a H2/He atmosphere under jovian conditions developed from actual laboratory data. The new model is based on a terrestrial model of Rosenkranz et al. (Rosenkranz, P.W. [1998]. Radio Science 33, 919-928), with substantial modifications to reflect the effects of jovian conditions. The new model for water vapor opacity dramatically outperforms previous models and will provide reliable results for temperatures from 300 to 525 K, at pressures up to 100 bars and at frequencies up to 6 GHz. These results will significantly reduce the uncertainties in the retrieval of jovian atmospheric water vapor abundances from the microwave radiometric measurements from the upcoming NASA Juno mission, as well as provide a clearer understanding of the role deep atmospheric water vapor may play in the decimeter-wavelength spectrum of Saturn.

Karpowicz, Bryan M.; Steffes, Paul G.

2011-03-01

211

Depth-resolved simplified characterization of collagen depletion in dermis with polarization sensitive optical coherence tomography applicable to non-laboratory conditions  

NASA Astrophysics Data System (ADS)

A further insight into the prior concept of polarization sensitive optical coherence tomography system intended for non-laboratory conditions is brought forward and an experimental proof-of-concept is presented. A phenomenological model is adopted from the theory of light depolarization in crystalline polymers and modified to yield a simplified algorithm for mapping depolarization ratio in dermis. The algorithm could distinguish between dermal layers with depleted collagen content and normal dermis of normal perilesional skin. Dermis is simulated by bireringent lamellae of collagen arranged chaotically in multiple layers parallel to the skin surface. Both the design concept and the model imply the sub-millimeter tumor thickness as a proofed prognostic factor and an important criterion for complementary functional diagnostics of skin cancers at their early phase of vertical growth. Choice of the model is inspired by similarity of structural and optical properties between liquid-crystal collagen fibers in dermis and birefringent crystalline lamellae in polymer materials. The numerical computation based on the model allowing for real characteristics of dermis gives plausible interpreting of depolarization peculiarities caused by collagen depletion. Feasibility is discussed of exploiting fiber optic analogs of achromatic retarders. Fabrication of the fiber retarders is shown to be realistic by making use of the photonics technology possessed by the authors.

Tougbaev, Vitali; Eom, Tae Joong; Shin, Woojin; Lee, Yeung Lak; Yu, Bong-Ahn; Kee, Chul-Sik; Ko, Do-Kyeong; Lee, Jongmin

2007-07-01

212

Influence of water hardness on accumulation and elimination of cadmium in two aquatic mosses under laboratory conditions.  

PubMed

This study investigated the effect of water hardness on the accumulation and elimination of cadmium (Cd) by two aquatic mosses, Fontinalis dalecarlica and Platyhypnidium riparioides, under laboratory conditions. The two mosses were exposed to nominal Cd concentrations of 0, 0.8, 2, and 10 microg . L-1, which includes the concentration range generally found in nature. The influence of three levels of water hardness (very soft: 11.7 mg . L-1; soft: 44.2 mg . L-1; and hard water: 92.3 mg . L-1 as CaCO3) was measured while maintaining the alkalinity and pH constant during the 28-day exposure. The Cd accumulation by the aquatic mosses was rapid, showing the potential of accumulation and the sensitivity of this biomonitor. Even if the actual Cd concentration in the water was low (concentration <0.15 microg . L-1 to 6.82 microg . L-1 of Cd), the uptake of Cd was very fast and mostly linear. This study was conducted in water hardness comparable to that found in the Canadian shield (hardness was <100 mg . L-1 as CaCO3). When the actual Cd concentration in the water was as high as 6.82 microg . L-1, the uptake of Cd was mostly linear and the steady state condition was not reach. Accumulation rates of Cd were significantly different when the mosses were in very soft (11.7 mg . L-1) as compared to hard water (92.3 mg . L-1 as CaCO3). The elimination of Cd followed a very slow process for the two species studied. The elimination rates of Cd from the mosses were not influenced by water hardness. PMID:9419268

Gagnon, C; Vaillancourt, G; Pazdernik, L

1998-01-01

213

Larval and juvenile Pacific herring Clupea pallasii are not susceptible to infectious hematopoietic necrosis under laboratory conditions  

USGS Publications Warehouse

Infectious hematopoietic necrosis (IHN) leads to periodic epidemics among certain wild and farmed fish species of the Northeast (NE) Pacific. The source of the IHN virus (IHNV) that initiates these outbreaks remains unknown; however, a leading hypothesis involves viral persistence in marine host species such as Pacific herring Clupea pallasii. Under laboratory conditions we exposed specific pathogen-free (SPF) larval and juvenile Pacific herring to 103 to 104 plaque-forming units (pfu) of IHNV ml–1 by waterborne immersion. Cumulative mortalities among exposed groups were not significantly different from those of negative control groups. After waterborne exposure, IHNV was transiently recovered from the tissues of larvae but absent in tissues of juveniles. Additionally, no evidence of viral shedding was detected in the tank water containing exposed juveniles. After intraperitoneal (IP) injection of IHNV in juvenile herring with 103 pfu, IHNV was recovered from the tissues of sub-sampled individuals for only the first 5 d post-exposure. The lack of susceptibility to overt disease and transient levels of IHNV in the tissues of exposed fish indicate that Pacific herring do not likely serve a major epizootiological role in perpetuation of IHNV among free-ranging sockeye salmon Oncorhynchus nerka and farmed Atlantic salmon Salmo salar in the NE Pacific.

Hart, L.M.; Traxler, G.S.; Garver, K.A.; Richard, J.; Gregg, J.L.; Grady, C.A.; Kurath, G.; Hershberger, P.K.

2011-01-01

214

Larval and juvenile Pacific herring Clupea pallasii are not susceptible to infectious hematopoietic necrosis under laboratory conditions.  

PubMed

Infectious hematopoietic necrosis (IHN) leads to periodic epidemics among certain wild and farmed fish species of the Northeast (NE) Pacific. The source of the IHN virus (IHNV) that initiates these outbreaks remains unknown; however, a leading hypothesis involves viral persistence in marine host species such as Pacific herring Clupea pallasii. Under laboratory conditions we exposed specific pathogen-free (SPF) larval and juvenile Pacific herring to 10(3) to 10(4) plaque-forming units (pfu) of IHNV ml(-1) by waterborne immersion. Cumulative mortalities among exposed groups were not significantly different from those of negative control groups. After waterborne exposure, IHNV was transiently recovered from the tissues of larvae but absent in tissues of juveniles. Additionally, no evidence of viral shedding was detected in the tank water containing exposed juveniles. After intraperitoneal (IP) injection of IHNV in juvenile herring with 10(3) pfu, IHNV was recovered from the tissues of sub-sampled individuals for only the first 5 d post-exposure. The lack of susceptibility to overt disease and transient levels of IHNV in the tissues of exposed fish indicate that Pacific herring do not likely serve a major epizootiological role in perpetuation of IHNV among free-ranging sockeye salmon Oncorhynchus nerka and farmed Atlantic salmon Salmo salar in the NE Pacific. PMID:21381516

Hart, Lucas M; Traxler, Garth S; Garver, Kyle A; Richard, Jon; Gregg, Jacob L; Grady, Courtney A; Kurath, Gael; Hershberger, Paul K

2011-01-21

215

Assessment of the leaching potential of 12 substituted phenylurea herbicides in two agricultural soils under laboratory conditions.  

PubMed

In this study, the potential groundwater pollution of 12 substituted phenylurea herbicides (chlorbromuron, chlorotoluron, diuron, fenuron, fluometuron, isoproturon, linuron, metobromuron, metoxuron, monolinuron, Monuron, and neburon) was investigated under laboratory conditions. For this purpose, leaching studies were conducted using disturbed soil columns filled with two different agricultural soils, one hypercalcic calcisol (HC) and the other endoleptic phaeozem (EP). In the case of the HC, all of the studied herbicides were found in leachates, while for the EP only, chlorbromuron, chlorotoluron, isoproturon, monolinuron, and, especially, fenuron were recovered. For both soils, the groundwater ubiquity score (GUS) index was calculated for each herbicide on the basis of its persistence (as t(1/2)) and mobility (as K(OC)). The half-lives obtained were markedly higher in the EP (217-518 days) than in the HC (71-178 days). As a consequence, higher values of GUS indexes were observed for EP. The ratio of the GUS between the EP and the HC was about 1.3. PMID:22578198

Navarro, Simón; Hernández-Bastida, Joaquín; Cazaña, Goretti; Pérez-Lucas, Gabriel; Fenoll, José

2012-05-30

216

Examination of food reward and energy intake under laboratory and free-living conditions in a trait binge eating subtype of obesity  

PubMed Central

Background/Aims: Trait binge eating has been proposed as a “hedonic subtype” of obesity characterized by enhanced food liking and wanting, and a preference for high-fat sweet foods in the laboratory. The current study examined the influence of trait binge eating in overweight or obese women on eating behavior under laboratory and free-living conditions over a 48-h period. Methods: In a matched pairs design, 24 overweight or obese females (BMI: 30.30 ± 2.60 kg/m2; Age: 25.42 ± 3.65 years) with high or low scores on the Binge Eating Scale (BSE) were divided into one of two groups; Obese Binge (O-B) and Obese Non-binge (O-NB). Energy intake was assessed using combined laboratory energy intake measures and 24-h dietary recall procedures. Liking and wanting were assessed using the Leeds Food Preference Questionnaire (LFPQ). Results: There was a significant association between overall energy consumed, and energy consumed from snack foods under laboratory and free-living conditions. O-B exhibited a greater preference for sweet snack foods in their laboratory and free-living eating behavior. These findings were supported by greater laboratory-based measures of wanting and craving for this food type in O-B. In addition, O-B consumed significantly more energy than their estimated daily energy requirements in the laboratory suggesting that they over-consumed compared to O-NB. Conclusions: The measurement concordance between laboratory and free-living based energy intake supports the validity of laboratory-based test meal methodologies Variation in trait binge eating was associated with increased craving and wanting for high-fat sweet foods and overconsumption in the laboratory. These findings support the use of trait binge eating as a common hedonic subtype of obesity and extend the relevance of this subtype to habitual patterns of energy intake. PMID:24155732

Dalton, Michelle; Blundell, John; Finlayson, Graham S.

2013-01-01

217

LABORATORY STUDY FOR THE REDUCTION OF CHROME (VI) TO CHROME (III) USING SODIUM METABISULFITE UNDER ACIDIC CONDITIONS  

SciTech Connect

This report describes the results from RPP-PLAN-32738, 'Test Plan for the Effluent Treatment Facility to Reduce Chrome(VI) to Chrome(I1I) in the Secondary Waste Stream', using sodium metabisulfite. Appendix A presents the report as submitted by the Center for Laboratory Sciences (CLS) to CH2M HILL Hanford Group, Inc. The CLS carried out the laboratory effort under Contract Number 21065, release Number 30. This report extracts the more pertinent aspects of the laboratory effort.

DUNCAM JB; GUTHRIE MD; LUECK KJ; AVILA M

2007-07-18

218

Pathogenicity of Beauveria bassiana isolated from Moroccan Argan forests soil against larvae of Ceratitis capitata (Diptera: Tephritidae) in laboratory conditions.  

PubMed

The Mediterranean fruit fly, Ceratitis capitata Wiedemann (Diptera: Tephritidae), is the major tephritid pest in Morocco. This pest survives in Moroccan forests Argania spinosa and continually invades the nearest agricultural areas. Entomopathogenic fungi are an interesting tool for fruit fly control and hold a useful alternative to conventional insecticides. However, primary selection of effective pathogens should be taken in laboratory condition prior to applying them in the field. Here, we used third late instar larvae of C. capitata to investigate the effectiveness of 15 local Beauveria bassiana isolates. Results showed that all isolates were able to infect the larval stage, producing a large mortality rate in puparia ranging from 65 to 95 % and caused significant reduction in adult emergence. The fungal treatments revealed that the mycosis occurred also in adults escaping infection as pupariating larvae. The percentage of mycosed puparia was highest in strain TAM6.2 (95 %) followed by ERS4.16 (90 %), therefore they were the most virulent. Median lethal concentration (LC??) was studied for five isolates at four concentrations ranging from 10? to 10? conidia ml?¹. The results showed that the slopes of regression lines for B. bassiana ERS4.16 (slope = 0.386) and TAM6.2 (slope = 0.41) were the most important and had the lowest LC?? values (2.85 × 10³ and 3.16 × 10³ conidia ml?¹ respectively). This investigation suggests that the soil of Argan forests contains pathogenic B. bassiana isolates and highlights for the first time their potential as biological control toward C. capitata larval stage in Morocco. PMID:24122125

Imoulan, Abdessamad; Elmeziane, Abdellatif

2014-03-01

219

Repellency of naturally occurring volatile alcohols to fungus gnat Bradysia sp. nr. coprophila (Diptera: Sciaridae) adults under laboratory conditions.  

PubMed

This study, conducted under laboratory conditions, was designed to determine the repellent activity of 10 naturally occurring volatile alcohol constituents against adults of the fungus gnat, Bradysia sp. nr. coprophila (Lintner) (Diptera: Sciaridae). The essential oil constituents were octanoic acid, furfural, acetophenone, benzaldehyde, dimethoxybenzene, borneol, menthol, 1-octen-3-ol, and 7-hydroxycitronellol, and alpha-terpineol. alpha-Terpineol, octanoic acid and furfural were tested at several concentrations, whereas the remaining seven were tested at only one concentration. The essential oil constituents' menthol, 1-octen-3-ol, and borneol displayed the most repellent activity. The mean percentage of fungus gnat adults recovered from the test compound petri dishes associated with the three essential oil constituents was between 6 and 15% compared with between 36 and 50% for the petri dishes with distilled water. The mean +/- SEM number of fungus gnat adults present in the sample compartments associated with menthol (10.4 +/- 2.6), 1-octen-3-ol (18.8 +/- 2.4), and borneol (23.4 +/- 5.6) was statistically lower than those in the petri dishes containing distilled water (60.9 +/- 7.4, 49.8 +/- 4.0, and 79.7 +/- 13.5), respectively. Only the highest concentration of alpha-terpineol (8.0 micromol) displayed significant repellent activity against fungus gnat adults. The other essential constituents tested, including octanoic acid (all three concentrations), furfural (both concentrations), acetophenone, dimethoxybenzene, and 7-hydroxycitronellol, were not statistically different from the distilled water control. The results of this study indicate that certain essential oil constituents repel fungus gnat adults, which may be useful, from a practical standpoint, in deterring adults from laying eggs into growing media. PMID:22066193

Cloyd, Raymond A; Marley, Karen A; Larson, Richard A; Dickinson, Amy; Arieli, Bari

2011-10-01

220

Testing Insecticidal Activity of Novel Chemically Synthesized siRNA against Plutella xylostella under Laboratory and Field Conditions  

PubMed Central

Background Over the last 60 years, synthetic chemical pesticides have served as a main tactic in the field of crop protection, but their availability is now declining as a result of the development of insect resistance. Therefore, alternative pest management agents are needed. However, the demonstration of RNAi gene silencing in insects and its successful usage in disrupting the expression of vital genes opened a door to the development of a variety of novel, environmentally sound approaches for insect pest management. Methodology/Principal Findings Six small interfering RNAs (siRNAs) were chemically synthesized and modified according to the cDNA sequence of P. xylostella acetylcholine esterase genes AChE1 and AChE2. All of them were formulated and used in insecticide activity screening against P. xylostella. Bioassay data suggested that Si-ace1_003 and Si-ace2_001 at a concentration of 3 µg cm?2 displayed the best insecticidal activity with 73.7% and 89.0%, mortality, respectively. Additional bioassays were used to obtain the acute lethal concentrations of LC50 and LC90 for Si-ace2_001, which were 53.66 µg/ml and 759.71 µg/ml, respectively. Quantitative Real-time PCR was used to confirm silencing and detected that the transcript levels of P. xylostella AChE2 (PxAChE2) were reduced by 5.7-fold compared to the control group. Consequently, AChE activity was also reduced by 1.7-fold. Finally, effects of the siRNAs on treated plants of Brassica oleracea and Brassica alboglabra were investigated with different siRNA doses. Our results showed that Si-ace2_001 had no negative effects on plant morphology, color and growth of vein under our experimental conditions. Conclusions The most important finding of this study is the discovery that chemically synthesized and modified siRNA corresponding to P. xylostella AChE genes cause significant mortality of the insect both under laboratory and field conditions, which provides a novel strategy to control P. xylostella and to develop bio-pesticides based on the RNA interference technology. PMID:23667556

Gong, Liang; Chen, Yong; Hu, Zhen; Hu, Meiying

2013-01-01

221

Laboratory insights into the chemical and kinetic evolution of several organic molecules under simulated Mars surface UV radiation conditions  

NASA Astrophysics Data System (ADS)

The search for organic carbon at the surface of Mars, as clues of past habitability or remnants of life, is a major science goal of Mars’ exploration. Understanding the chemical evolution of organic molecules under current martian environmental conditions is essential to support the analyses performed in situ. What molecule can be preserved? What is the timescale of organic evolution at the surface? This paper presents the results of laboratory investigations dedicated to monitor the evolution of organic molecules when submitted to simulated Mars surface ultraviolet radiation (190-400 nm), mean temperature (218 ± 2 K) and pressure (6 ± 1 mbar) conditions. Experiments are done with the MOMIE simulation setup (for Mars Organic Molecules Irradiation and Evolution) allowing both a qualitative and quantitative characterization of the evolution the tested molecules undergo (Poch, O. et al. [2013]. Planet. Space Sci. 85, 188-197). The chemical structures of the solid products and the kinetic parameters of the photoreaction (photolysis rate, half-life and quantum efficiency of photodecomposition) are determined for glycine, urea, adenine and chrysene. Mellitic trianhydride is also studied in order to complete a previous study done with mellitic acid (Stalport, F., Coll, P., Szopa, C., Raulin, F. [2009]. Astrobiology 9, 543-549), by studying the evolution of mellitic trianhydride. The results show that solid layers of the studied molecules have half-lives of 10-103 h at the surface of Mars, when exposed directly to martian UV radiation. However, organic layers having aromatic moieties and reactive chemical groups, as adenine and mellitic acid, lead to the formation of photoresistant solid residues, probably of macromolecular nature, which could exhibit a longer photostability. Such solid organic layers are found in micrometeorites or could have been formed endogenously on Mars. Finally, the quantum efficiencies of photodecomposition at wavelengths from 200 to 250 nm, determined for each of the studied molecules, range from 10-2 to 10-6 molecule photon-1 and apply for isolated molecules exposed at the surface of Mars. These kinetic parameters provide essential inputs for numerical modeling of the evolution of Mars’ current reservoir of organic molecules. Organic molecules adsorbed on martian minerals may have different kinetic parameters and lead to different endproducts. The present study paves the way for the interpretation of more complex simulation experiments where organics will be mixed with martian mineral analogs.

Poch, O.; Kaci, S.; Stalport, F.; Szopa, C.; Coll, P.

2014-11-01

222

Effects of Beauveria bassiana on Survival, Blood-Feeding Success, and Fecundity of Aedes aegypti in Laboratory and Semi-Field Conditions  

PubMed Central

The fungus Beauveria bassiana reduces Aedes aegypti longevity in laboratory conditions, but effects on survival, blood-feeding behavior, and fecundity in realistic environmental conditions have not been tested. Adult, female Ae. aegypti infected with B. bassiana (FI-277) were monitored for blood-feeding success and fecundity in the laboratory. Fungal infection reduced mosquito-human contact by 30%. Fecundity was reduced by (mean ± SD) 29.3 ± 8.6 eggs per female per lifetime in the laboratory; egg batch size and viability were unaffected. Mosquito survival, blood-feeding behavior, and fecundity were also tested in 5 meter×7 meter×4 meter semi-field cages in northern Queensland, Australia. Fungal infection reduced mosquito survival in semi-field conditions by 59–95% in large cages compared with 61–69% in small cages. One semi-field cage trial demonstrated 80% reduction in blood-feeding; a second trial showed no significant effect. Infection did not affect fecundity in large cages. Beauveria bassiana can kill and may reduce biting of Ae. aegypti in semi-field conditions and in the laboratory. These results further support the use of B. bassiana as a potential biocontrol agent against Ae. aegypti. PMID:22492151

Darbro, Jonathan M.; Johnson, Petrina H.; Thomas, Matthew B.; Ritchie, Scott A.; Kay, Brian H.; Ryan, Peter A.

2012-01-01

223

Ranking the significance of fermentation conditions on the volatile organic compounds of Tuber melanosporum fermentation system by combination of head-space solid phase microextraction and chromatographic fingerprint similarity analysis.  

PubMed

Tuber melanosporum is highly appreciated in culinary contexts due to its unique and characteristic aroma. T. melanosporum fermentation has been established as a promising alternative for fruiting bodies to produce volatile organic compounds (VOCs). In this work, a technique using a combination of chromatographic fingerprint similarity analysis, head-space solid phase microextraction and gas chromatography was developed to rank the significance of fermentation conditions on the VOCs profile during T. melanosporum fermentation. Omission tests indicated that the absence of major carbon source (i.e., sucrose) in the fermentation media had the most significant effect on the profile of VOCs, followed by the absence of yeast extract or peptone. Consideration of the culture conditions revealed that VOCs produced was the most significantly affected by temperature. These results indicated that it is possible to adjust the aroma of truffles via fermentation process control. PMID:23943007

Li, Dao-Cheng; Liu, Rui-Sang; Li, Hong-Mei; Yuan, Zhan-Peng; Chen, Tao; Tang, Ya-Jie

2014-03-01

224

Composed Computational Verb Similarities  

Microsoft Academic Search

Computational verb similarities are used to measure the degree of similarities between two waveforms. Since the similarities of waveforms might be measured based on their distance, trends, frequencies and many other factors, it is easy to consider the contributions of these factors to computational verb similarities separately and then combine them into composed computational verb similarities. In this paper, different

Tao Yang

2009-01-01

225

A Laboratory Exercise to Illustrate Increased Salivary Cortisol in Response to Three Stressful Conditions Using Competitive ELISA  

ERIC Educational Resources Information Center

Perceived stress activates the hypothalamus-pituitary-adrenal axis, resulting in the release of glucocorticoids into the systemic circulation. Glucocorticoids cause the elevation of blood glucose, providing the necessary energy for the organism to cope with stress. Here, we outline a laboratory exercise that uses a competitive ELISA kit to…

Haussmann, Mark F.; Vleck, Carol M; Farrar, Eugenia S.

2007-01-01

226

Influence of mite infestation on the longevity and fecundity of the mosquito Mansonia uniformis (Diptera: Insecta) under laboratory conditions  

Microsoft Academic Search

A study relating to the influence of mite infestation on the longevity and fecundity of the mosquito,Mansonia uniformis was carried out in the laboratory. It was found that the mite parasitism does influence the quantity of blood ingested, survivorship\\u000a and the time lag between feeding and egg-laying. However fecundity and hatching percentages were not affected.

R. Rajendran; R. S. Prasad

1992-01-01

227

Influence of cadmium on the metabolic quotient, l -?:? d -glutamic acid respiration ratio and enzyme activity?:?microbial biomass ratio under laboratory conditions  

Microsoft Academic Search

This study was carried out to investigate the effect of very high cadmium concentrations (50 and 500??g Cd g–1 soil) on some biochemical and microbiological measurements under laboratory conditions involving daily soil samplings. The\\u000a data for both DTPA- and water-soluble Cd showed two distinctive patterns during soil incubation; from 0 to 4?days, values\\u000a were about 50–500 and 1–100??g g–1 dry

L. Landi; G. Renella; J. L. Moreno; L. Falchini; P. Nannipieri

2000-01-01

228

Effects of shelter type and food supply frequency on survival and growth of stage-2 juvenile white-clawed crayfish (Austropotamobius pallipes Lereboullet) under laboratory conditions  

Microsoft Academic Search

Two shelter substrates (fibre-cement sheets and PVC pipes) and two foodsupply frequencies (once and twice daily) were tested on white-clawed juvenilecrayfish in two separate experiments performed under laboratory conditions.Juvenile crayfish were maintained at an initial density of 50 animals persquaremetre in a flow-through system and fed on fresh Daphniapulex and a feed formulated for rainbow trout. After 120 days,highersurvival (50.5%),

M. Sáez-Royuela; J. M. Carral; J. D. Celada; J. R. Pérez

2002-01-01

229

Studies on the larval development of northeastern Atlantic and Mediterranean Procellanidae (Decapoda, Anomura). I — Redescription of the larval stages of Porcellana platycheles (Pennant, 1777) reared under laboratory conditions  

Microsoft Academic Search

The complete larval development is described forPorcellana platycheles (Pennant) reared under laboratory conditions. The development consists of two zoeal stages and one megalopa. At 20C and\\u000a 35‰ salinity, the megalopa appeared 17–18 days after hatching. Survival was 56% from hatching to the megalopa stage. The morphological\\u000a features of the zoeal and megalopa stages ofP. platycheles are compared with those of

J. I. González-Gordillo; J. A. Cuesta; A. Rodríguez

1996-01-01

230

Evaluation of a bioluminescence method, contact angle measurements and topography for testing the cleanability of plastic surfaces under laboratory conditions  

NASA Astrophysics Data System (ADS)

Detection of adenosine triphosphate (ATP) by bioluminescence is used, for instance, in the food industry and in hospitals to assess the hygiene status of surfaces. The aim of this laboratory study was to investigate the feasibility of the ATP method for estimating the cleanability of resilient floor coverings from biological soil. The surfaces were worn using a Soiling and Wearing Drum Tester, and soiled and cleaned with an Erichsen Washability and Scrubbing Resistance Tester. In the laboratory test carried out with the bioluminescence method, most of the new and worn floor coverings that were biologically soiled were cleaned efficiently. According to this study, the semiquantitative ATP screening method can be used for hygiene monitoring of flooring materials. No correlation was found between cleanability and contact angles or surface topography measured using a profilometer. However, by revealing local irregularities and damage on surfaces, scanning electron micrographs appeared useful in explaining differences in cleanability.

Redsven, I.; Kymäläinen, H.-R.; Pesonen-Leinonen, E.; Kuisma, R.; Ojala-Paloposki, T.; Hautala, M.; Sjöberg, A.-M.

2007-04-01

231

Effect of different cole crops on the biological parameters of Pieris brassicae (L.) (Lepidoptera: Pieridae) under laboratory conditions  

Microsoft Academic Search

The effect of different cole crops was studied on biological parameters of Pieris brassicae (L.) in the laboratory at 28 °C, 65% RH, and 12L:12D photoperiod. The results indicated that host plants significantly affected\\u000a the life history, i.e. survival of developmental stages, oviposition period, and sex ratio of P. brassicae. Comparative study on different host plant revealed that P. brassicae

Fazil Hasan; M. Shafiq Ansari

2010-01-01

232

Religious Similarity Among Siblings  

E-print Network

of this similarity. The results of this thesis demonstrate that siblings share common levels of religiosity. The similarity was still moderate after controlling for known predictors of adolescent religiosity such as parental influence, religious affiliation, race...

Field, Layton

2012-07-11

233

Soil structure, colloids, and chemical transport as affected by short-term reducing conditions: a laboratory study  

NASA Astrophysics Data System (ADS)

Upland soils in the Midwestern US often undergo reducing conditions when soils are temporally flooded during the spring and remain water saturated for days or weeks. Short-term reducing conditions change the chemistry of the soil and may affect soil structure and solution chemical transport. The effects of short-term reducing conditions on chemical and physical properties of the soils, colloids, and associated chemical/nutrients transport are still not well understood and was the objective of our study. A biogeochemical reactor was built to achieve reducing conditions. Three cultivated and three uncultivated soils with different organic carbon contents were incubated in the reactor for 1 hour and 3 days under anaerobic conditions. Effects of the redox state on soil structure (pore size distribution) and drainable porosity, colloids mobility, and chemical transport were determined using high energy moisture characteristic and analytical methods. After each treatment, the soil solution was collected for redox potential (Eh), pH, and electrical conductivity (EC) measurements, and chemical analysis of metals (Ca, Mg, K), nutrients (N, P), and dissolved organic carbon. Strongly reducing conditions were achieved after 3 days of incubation and were followed by a decrease in soil porosity and an increase in pH, EC, clay dispersion, swelling, colloids mobility, and associated chemical transport. The trend for each soil depended on their initial structural stability and chemical properties. The structure of cultivated soils and the leaching of nutrients and carbon from uncultivated soils were more sensitive to the redox state. A strong correlation was found between changes in Eh and drainable porosity. The role of short-term reducing conditions on changes in redox sensitive elements, organic matter decomposition, pH, and EC and their influence on soil structure and soil particles or colloids/chemical transport for both soil groups are discussed in the paper. This study showed that short- term reducing conditions influence colloids/chemical transport and it should be taken into account for modeling because dissolved compounds and colloids facilitated nutrient and associated pollutant transport during coupled overland and soil-matrix flow conditions.

de-Campos, A. B.; Mamedov, A. I.; Huang, C.; Wagner, L. E.

2008-12-01

234

Biofilm Formation by Gram-Negative Bacteria on Central Venous Catheter Connectors: Effect of Conditioning Films in a Laboratory Model  

Microsoft Academic Search

Human blood components have been shown to enhance biofilm formation by gram-positive bacteria. We investigated the effect of human blood on biofilm formation on the inner lumen of needleless central venous catheter connectors by several gram-negative bacteria, specifically Enterobacter cloacae, Pseudomonas aerugi- nosa, and Pantoea agglomerans. Results suggest that a conditioning film of blood components promotes biofilm formation by these

R. Murga; J. M. Miller; R. M. Donlan

2001-01-01

235

Biosimilar Insulins: How Similar is Similar?  

PubMed Central

Biosimilar insulins (BIs) are viewed as commercially attractive products by a number of companies. In order to obtain approval in the European Union or the United States, where there is not a single BI currently on the market, a manufacturer needs to demonstrate that a given BI has a safety and efficacy profile that is similar to that of the “original” insulin formulation that is already on the market. As trivial as this may appear at first glance, it is not trivial at all for a good number of reasons that will be discussed in this commentary. As with protein manufacturing, modifications in the structure of the insulin molecule can take place (which can have serious consequences for the biological effects induced), so a rigid and careful assessment is absolutely necessary. The example of Marvel's failed application with the European Medicines Agency provides insights into the regulatory and clinical challenges surrounding the matter of BI. Although a challenging BI approval process might be regarded as a hurdle to keep companies out of certain markets, it is fair to say that the potential safety and efficacy issues surrounding BI are substantial and relevant and do warrant a careful and evidence-driven approval process. PMID:21722590

Heinemann, Lutz; Hompesch, Marcus

2011-01-01

236

Methane evolution from UV-irradiated spacecraft materials under simulated martian conditions: Implications for the Mars Science Laboratory (MSL) mission  

NASA Astrophysics Data System (ADS)

Fifteen organic and three inorganic compounds were tested for methane (CH 4) evolution under simulated martian conditions of 6.9 mbar; UVC (200-280 nm) flux of 4 W m -2; 20 °C; simulated optical depth of 0.1; and a Mars gas composition of CO 2 (95.3%), N 2 (2.7%), Ar (1.7%), O 2 (0.13%), and water vapor (0.03%). All three inorganic compounds (i.e., NaCl, CaCO 3, graphite) failed to evolve methane at the minimum detection level 0.5 ppm, or above. In contrast, all organic compounds evolved methane when exposed to UV irradiation under simulated martian conditions. The polycyclic aromatic hydrocarbon, pyrene, released the most methane per unit of time at 0.175 nmol CH 4 g -1 h -1, and a spectral reflectance target material used for the MER rovers and Phoenix lander released the least methane at 0.00065 nmol CH 4 cm -2 h -1. Methane was also released from UV-killed bacterial endospores of Bacillus subtilis. Although all organic compounds evolved methane when irradiated with UV photons under martian conditions, the concentrations of residual organics, biogenic signature molecules, and dead microbial cells should be relatively low on the exterior surfaces of the MSL rover, and, thus, not significant sources of methane contamination. In contrast, kapton tape was found to evolve methane at the rate of 0.00165 nmol CH 4 cm -2 h -1 (16.5 nmol m -2 h -1) under the UV and martian conditions tested. Although the evolution of methane from kapton tape was found to decline over time, the large amount of kapton tape used on the MSL rover (lower bound estimated at 3 m 2) is likely to create a significant source of terrestrial methane contamination during the early part of the mission.

Schuerger, Andrew C.; Clausen, Christian; Britt, Daniel

2011-05-01

237

Design and laboratory testing of a chamber device to measure total flux of volatile organic compounds from the unsaturated zone under natural conditions  

NASA Astrophysics Data System (ADS)

To determine if an aquifer contaminated with volatile organic compounds (VOCs) has potential for natural remediation, all natural processes affecting the fate and transport of VOCs in the subsurface must be identified and quantified. This research addresses the quantification of air-phase volatile organic compounds (VOCs) leaving the unsaturated zone soil gas and entering the atmosphere—including the additional flux provided by advective soil-gas movement induced by barometric pumping. A simple and easy-to-use device for measuring VOC flux under natural conditions is presented. The vertical flux chamber (VFC) was designed using numerical simulations and evaluated in the laboratory. Mass-balance numerical simulations based on continuously stirred tank reactor equations (CSTR) provided information on flux measurement performance of several sampling configurations with the final chamber configuration measuring greater than 96% of model-simulated fluxes. A laboratory device was constructed to evaluate the flux chamber under both diffusion-only and advection-plus-diffusion transport conditions. The flux chamber measured an average of 82% of 15 diffusion-only fluxes and an average of 95% of 15 additional advection-plus-diffusion flux experiments. The vertical flux chamber has the capability of providing reliable measurement of VOC flux from the unsaturated zone under both diffusion and advection transport conditions.

Tillman, Fred D.; Smith, James A.

2004-11-01

238

On-road and laboratory investigations on non-exhaust ultrafine particles from the interaction between the tire and road pavement under braking conditions  

NASA Astrophysics Data System (ADS)

We investigated the physical and chemical characteristics of non-exhaust ultrafine particles from on-road driving and laboratory measurements using a mobile sampling vehicle. The on-road driving and laboratory measurements during constant speed conditions revealed no enhancement of ultrafine particles. Under braking events, the total number concentrations of tire particles (TPs) sampled 90 mm above the road surface was 6 times higher with broader mode diameters when compared to 40 mm above the road surface. In contrast to braking events, under cornering conditions, the total number concentrations of TPs sampled 40 mm above the road surface were 50 times higher relative to 90 mm above the road surface. From the morphological and elemental analyses, it is likely that the ultrafine particles generated from the interaction between the tire and the road surface under braking conditions might originated from sulfur-containing materials or anti-oxidants which are contained in TPs, and/or graphite and solid lubricants which are mainly present in brake particles (BPs). However, Zn which was a distinguishing elemental marker of tire wear particles didn't show in EDS spectra. Further research would be required as to the exact emission source of ultrafine particles.

Kwak, Jihyun; Lee, Sunyoup; Lee, Seokhwan

2014-11-01

239

Similarity spectra analysis of high-performance jet aircraft noise.  

PubMed

Noise measured in the vicinity of an F-22A Raptor has been compared to similarity spectra found previously to represent mixing noise from large-scale and fine-scale turbulent structures in laboratory-scale jet plumes. Comparisons have been made for three engine conditions using ground-based sideline microphones, which covered a large angular aperture. Even though the nozzle geometry is complex and the jet is nonideally expanded, the similarity spectra do agree with large portions of the measured spectra. Toward the sideline, the fine-scale similarity spectrum is used, while the large-scale similarity spectrum provides a good fit to the area of maximum radiation. Combinations of the two similarity spectra are shown to match the data in between those regions. Surprisingly, a combination of the two is also shown to match the data at the farthest aft angle. However, at high frequencies the degree of congruity between the similarity and the measured spectra changes with engine condition and angle. At the higher engine conditions, there is a systematically shallower measured high-frequency slope, with the largest discrepancy occurring in the regions of maximum radiation. PMID:23556581

Neilsen, Tracianne B; Gee, Kent L; Wall, Alan T; James, Michael M

2013-04-01

240

Rhythmic similarity through elaboration  

Microsoft Academic Search

Rhythmic similarity techniques for audio tend to eval- uate how close to identical two rhythms are. This pa- per proposes a similarity metric based on rhythmic elaboration that matches rhythms that share the same beats regardless of tempo or identicalness. Elabora- tions can help an application decide where to transi- tion between songs. Potential applications include au- tomatically generating a

M. Parry; I. Essa

2003-01-01

241

The Gender Similarities Hypothesis  

ERIC Educational Resources Information Center

The differences model, which argues that males and females are vastly different psychologically, dominates the popular media. Here, the author advances a very different view, the gender similarities hypothesis, which holds that males and females are similar on most, but not all, psychological variables. Results from a review of 46 meta-analyses…

Hyde, Janet Shibley

2005-01-01

242

Similarity and Congruence.  

ERIC Educational Resources Information Center

This instructional unit is an introduction to the common properties of similarity and congruence. Manipulation of objects leads to a recognition of these properties. The ASA, SAS, and SSS theorems are not mentioned. Limited use is made in the application of the properties of size and shape preserved by similarity or congruence. A teacher's guide…

Herman, Daniel L.

243

Finding similar faces  

Microsoft Academic Search

In this paper, we propose a method to match similar faces despite photos, which are taken from different sources on Internet, could have different scenes, illumination and posing. Interest points are used to recognize faces, and some points are eliminated in order to find best matching points which pair the similar face. Difference between two matching points is used to

R. Baturalp Torun; Merve Yurdakul; Pinar Duygulu

2009-01-01

244

Processes of Similarity Judgment  

ERIC Educational Resources Information Center

Similarity underlies fundamental cognitive capabilities such as memory, categorization, decision making, problem solving, and reasoning. Although recent approaches to similarity appreciate the structure of mental representations, they differ in the processes posited to operate over these representations. We present an experiment that…

Larkey, Levi B.; Markman, Arthur B.

2005-01-01

245

Similarity and Group Performance  

ERIC Educational Resources Information Center

This paper investigates the effects that different patterns of similarity among group members have on a group's performance on a problem-solving task. I discuss and test hypotheses on the effects of similarity on group performance derived from two literatures: balance theory and research on homophily. In an experiment I found that the relative…

Civettini, Nicole H. W.

2007-01-01

246

Estimating time-to-gravid for a freshwater mussel, Utterbackia imbecillis (Unionidae), after temperature conditioning in the laboratory  

SciTech Connect

The juvenile of Utterbackia imbecillis has recently become an important toxicity test organism. However, in temperate climates, gravid U. imbecillis are not readily available during many months of the year, especially if shoreline collection methods are used. This shortage of gravid mussels presents a logistical problem for use of juvenile U. imbecillis as toxicity test organisms. Therefore, this study was designed to test the feasibility of delaying and manipulating glochidial maturation in the laboratory through temperature control, because temperature changes seem to cue the maturation of glochidia in gravid mussels in the natural environment. The objectives of this study were to determine whether glochidial maturation can be stalled by holding adult mussels at cold temperatures, to determine if glochidial maturation could be cued by increasing water temperature at the time juveniles are needed for toxicity testing, and to predict the time required for cold-stored mussels to become gravid. Results of this study suggest that glochidial maturation can be stalled by holding mussels at winter temperature. Furthermore, glochidial maturation can later be cued by increasing the water temperature. Additionally, a survival analysis method is suitable for estimating the time-to-gravid for cold-stored mussels. These results should be useful for researchers requiring year-round availability of U. imbecillis for toxicity testing.

Vreede, K.B. van; MacIntosh, D.L.; Black, M.C.

1999-07-01

247

The merits of designed ELISA avidity kit in detection of Toxoplasma gondii IgG antibody in laboratory conditions  

PubMed Central

Background: Toxoplasmosis is a parasitic disease which may cause some laboratory symptoms in infected individuals. One of the main ways to transmit this organism is placenta to the fetus pathway. If this transmission occurs in the 3rd month of pregnancy, the abortion, central nerve system and ocular disorder will happen. Because of this issue, the precise technique for the detection of Toxoplasma antibodies such as immunoglobulin G (IgG) and immunoglobulin M IgM are important, as they contain ELISA and ELISA avidity. Materials and Methods: In this survey, the main samples are serum and amniotic fluid that were collected from 48 pregnant women infected with Toxoplasma gondii in Shariaty hospital. This survey is attempted to design ELISA avidity kit in Tarbiat Modates University. Results: The results from this survey show that, in these total pregnant women the infection by T. gondii has occurred and many of them are infected currently. Conclusions: In the simple ELISA technique, the only antibody that can be detected precisely is IgM; however, using this technique the IgG antibody can also be detected. In this new technique or ELISA avidity, in addition to detection of IgG antibody against T. gondii, the month of transmission of Toxoplasma is also interpreted. PMID:23961440

Sadraie, Javid; Bahadory, Ehsan Shariat; Marsusi, Vajihe

2013-01-01

248

Glutathione, glutathione-dependent and antioxidant enzymes in mussel, Mytilus galloprovincialis, exposed to metals under field and laboratory conditions: implications for the use of biochemical biomarkers  

Microsoft Academic Search

The effects of exposure to metals under and laboratory conditions were investigated in the Mediterranean mussel Mytilus galloprovincialis. The examined biological responses included the concentrations of heavy metals, the level of glutathione, and the activity of several enzymes selected among glutathione-dependent oxidoreductases and hydrolases: glutathione reductase. EC1.6.4.2; glyoxalase I, EC4.4.1.5; glyoxalase II, EC3.1.2.6; glutathione S-transferases, EC2.5.1.18; Se-dependent, EC1 11.1.9 and

Francesco Regoli; Giovanni Principato

1995-01-01

249

Laboratory measurements of the microwave opacity of gaseous ammonia (NH3) under simulated conditions for the Jovian atmosphere  

NASA Technical Reports Server (NTRS)

Microwave opacity measurements have been conducted for gaseous ammonia simulating Jovian atmosphere conditions at five frequencies from 18.5 to 1.38 cm, at temperatures from 178 to 300 K and 1-6 atm pressures. The atmospheric composition is 90-percent H/10-percent He. In the 1.38-18.5 cm wavelength range, ammonia absorption is well expressed by Berge and Gulkis' (1976) lineshape. The results obtained suggest that either an ammonia abundance 1.5-2.0 times greater than solar must be present at less than 1-2 bar, or some other microwave absorber is present.

Steffes, Paul G.; Jenkins, Jon M.

1987-01-01

250

Short-term evaluation of visible implant alpha tags in juveniles of three fish species under laboratory conditions.  

PubMed

Visible implant alpha (VI alpha) tag-induced changes in mortality and condition, as well as tag retention and readability, were examined during a 4-week period for juveniles of three fish species: tiger muskellunge Esox masquinongy × Esox lucius (91?±?7?mm total length, L(T), mean?±?s.d.), Snake River cutthroat trout Oncorhynchus clarki behnkei (84?±?8?mm) and rainbow trout Oncorhynchus mykiss (85?±?5?mm). Mortality and condition did not differ between tagged fish and control fish for any species and overall tag retention rates were high (92% for E. masquinongy × E. lucius, 91% for O. c. behnkei and 100% for O. mykiss). Short-term readability of VI alpha tags was low in juvenile E. masquinongy × E. lucius and juvenile O. c. behnkei. Therefore, it is not recommend to use VI alpha tags in juvenile E. masquinongy × E. lucius or juvenile O. c. behnkei for periods >2?weeks, but VI alpha tags seem to be suitable for juvenile O. mykiss for a period of at least 4?weeks. PMID:24689672

Turek, K C; Pegg, M A; Pope, K L

2014-04-01

251

Intercomparison exercise on external gamma dose rate under field conditions at the laboratory of natural radiation (Saelices el Chico, Spain).  

PubMed

The last nuclear accident in Fukushima nuclear power plant has increased the necessity for measuring radiation in the environment. Therefore, radiation monitors providing results traceable throughout the country become essential and it is very important to test them under the same environmental conditions. The first intercomparison of natural radioactivity under field conditions was held in Saelices el Chico (Salamanca, Spain) in May 2011, including an exercise on environmental dose rate. This article presents the results achieved by 19 instruments belonging to 12 institutions from 7 different countries. The tested detectors are proportional counters, ionisation chambers, Geiger-Müller and scintillators measuring dose rate in three stations with reference values from 110 to 1800 nGy h(-1). All the results were given in terms of air kerma (nGy h(-1)) and the measurements show agreement within 25 % in all the sites. Evaluation criteria based on accuracy and statistical uncertainty were also carried out and 25 % of participants passed the test in all sites. PMID:23413092

Gutierrez-Villanueva, J L; Sainz-Fernández, C; Fuente-Merino, I; Sáez-Vergara, J C; Correa-Garcés, E; Quindos-Poncela, L S

2013-08-01

252

Role of microorganisms in emission of nitrous oxide and methane in pulse cultivated soil under laboratory incubation condition.  

PubMed

Soil from a pulse cultivated farmers land of Odisha, India, have been subjected to incubation studies for 40 consecutive days, to establish the impact of various nitrogenous fertilizers and water filled pore space (WFPS) on green house gas emission (N2O & CH4). C2H2 inhibition technique was followed to have a comprehensive understanding about the individual contribution of nitrifiers and denitrifiers towards the emission of N2O. Nevertheless, low concentration of C2H2 (5 ml: flow rate 0.1 kg/cm(2)) is hypothesized to partially impede the metabolic pathways of denitrifying bacterial population, thus reducing the overall N2O emission rate. Different soil parameters of the experimental soil such as moisture, total organic carbon, ammonium content and nitrate-nitrogen contents were measured at regular intervals. Application of external N-sources under different WFPS conditions revealed the diverse role played by the indigenous soil microorganism towards green house gas emission. Isolation of heterotrophic microorganisms (Pseudomonas) from the soil samples, further supported the fact that denitrification might be prevailing during specific conditions thus contributing to N2O emission. Statistical analysis showed that WFPS was the most influential parameter affecting N2O formation in soil in absence of an inhibitor like C2H2. PMID:24426084

Jena, Jyotsnarani; Ray, Sanak; Srichandan, Haragobinda; Das, Anuradha; Das, Trupti

2013-03-01

253

Behavioral responses of the Iberian waterfrog, Pelophylax perezi (Seoane, 1885), to three nitrogenous compounds in laboratory conditions.  

PubMed

Several studies have assessed the effects of nitrogenous compounds on amphibian behavior. However, few have focused on the effects of their combination with other stressors or on the variation of the response to pollutants among populations. We analyzed the effect of nitrogenous compounds (NH(4)(+); NO(2)(-); NO(3)(-), both alone and in combination) on larval behavior (activity level and location in the water column) in four populations of Pelophylax perezi naturally exposed to different levels of eutrophication. Larval activity was highest and use of the bottom of the experimental beaker was lowest at lower concentrations of nitrogenous compounds acting singly, these responses being minimal and maximal, respectively, at both control and higher concentrations. This pattern appears to fit to an hormetic response. Additionally, the combination of nitrogenous compounds affected more severely the response variables than when ammonium or nitrite acted singly according to an additive model. Populations inhabiting highly polluted aquatic habitats marginally showed higher activity level than the populations from less polluted environments, especially when larvae were exposed to ammonium or when nitrite appeared in combination with other nitrogen forms. Levels of activity correlated positively with larval final mass. Moreover, for similar levels of activity, larvae from polluted populations had higher growth rates than those coming from reference populations which suggests interdemic differences in behavioral sensitivity to nitrogenous pollutants. PMID:21512748

Egea-Serrano, Andrés; Tejedo, Miguel; Torralva, Mar

2011-08-01

254

Graph similarity and matching  

E-print Network

Measures of graph similarity have a broad array of applications, including comparing chemical structures, navigating complex networks like the World Wide Web, and more recently, analyzing different kinds of biological data. ...

Zager, Laura (Laura A.)

2005-01-01

255

Optimum conditions for growth in liquid medium of Oscillatoria formosa Bory used as the principal food in laboratory culture of intermediate hosts for schistosomosis and fasciolosis.  

PubMed

The rearing of snails, intermediate hosts of Schistosoma haematobium, S. intercalatum, S. bovis and Fasciola hepatica is the first step to maintain the life cycle of these parasites in laboratory in order to have biological material for the different studies, namely on the systematic biology and immunodiagnostic of schistosomosis and fasciolosis. According to the traditional method, the alga Oscillatoria formosa Bory (Cyanobacteria), principal food source for the snails, was cultivated in soil extract (Sampaio Xavier et al., 1968). However, it was sometimes very difficult to find the proper soil extract and the material was also contaminated by protozoa and fungi. In our work, using a new medium having as a base the Mineral Medium II (modified from Hughes et al., 1958) we found that O. formosa had a better growth response than in the soil extract medium. Snails fed on O. formosa reached three times the size of others at the same age, and they also reached sex maturity earlier, having more egg-masses per snail and, in addition, the rate of survival as well as the number of generations per year under laboratory conditions significantly increased. This culture was also easier to perform, and the axenic conditions easier to maintain. PMID:11031760

Ferreira Filipa, M; Delgado, M L; Seixas Lopes, A M; Sampaio Silva, M S

2000-09-01

256

Isoform-specific quantification of metallothionein in the terrestrial gastropod Helix pomatia. II. A differential biomarker approach under laboratory and field conditions.  

PubMed

The two function-specific metallothionein (MT) isoforms characterized from the midgut gland and mantle tissue of Helix pomatia differ substantially in their metal-binding preferences, as well as molecular and biochemical features. These differences make them potential candidates for biomarker studies based on a differential, isoform-specific approach. To prove this hypothesis, induction experiments with two metals (Cd and Cu) that are normally bound by the two isoforms were compared with a range of organic chemicals and physical stressors under laboratory conditions to test the responsiveness of the two isoforms to the stressors applied. In addition, field studies were conducted with Roman snails and substrate samples collected from different metal-contaminated sites in Austria to test the suitability of the two isoforms as biomarkers under field conditions. The results of these combined laboratory and field studies confirmed the validity of the biomarker approach with the two metal- and tissue-specific isoforms. It is demonstrated that the Cd-binding MT specifically and exclusively responds to Cd exposure by increasing concentrations, whereas the Cu-binding MT isoform decreases in its concentration upon exposure to physical stress (X-ray irradiation and cold). This suggests researchers should adopt, under certain preconditions, a dual biomarker approach by combining the simultaneous quantification of Cd-MT concentrations in the midgut gland as a biomarker for Cd pollution and of Cu-MT concentration in the mantle as a biomarker for the impairment of snails by additional physical stressors. PMID:15095885

Dallinger, Reinhard; Chabicovsky, Monika; Lagg, Bernhard; Schipflinger, Rouven; Weirich, Harald G; Berger, Burkhard

2004-04-01

257

Effect of Commercial Cyanobacteria Products on the Growth and Antagonistic Ability of Some Bioagents under Laboratory Conditions  

PubMed Central

Evaluation of the efficacy of blue-green algal compounds against the growth of either pathogenic or antagonistic microorganisms as well as their effect on the antagonistic ability of bioagents was studied under in vitro conditions. The present study was undertaken to explore the inhibitory effect of commercial algal compounds, Weed-Max and Oligo-Mix, against some soil-borne pathogens. In growth medium supplemented with these algal compounds, the linear growth of pathogenic fungi decreased by increasing tested concentrations of the two algal compounds. Complete reduction in pathogenic fungal growth was observed at 2% of both Weed-Max and Oligo-Mix. Gradual significant reduction in the pathogenic fungal growth was caused by the two bioagents and by increasing the concentrations of algal compounds Weed-Max and Oligo-Mix. The present work showed that commercial algal compounds, Weed-Max and Oligo-Mix, have potential for the suppression of soil-borne fungi and enhance the antagonistic ability of fungal, bacterial, and yeast bio-agents. PMID:24307948

El-Mougy, Nehal S.; Abdel-Kader, Mokhtar M.

2013-01-01

258

Effect of farm and simulated laboratory cold environmental conditions on the performance and physiological responses of lactating dairy cows supplemented with bovine somatotropin (BST)  

NASA Astrophysics Data System (ADS)

A study was conducted to evaluate the effect of bovine somatotropin (BST) supplementation in twelve lactating dairy cows maintained in cold environmental conditions. Six cows were injected daily with 25 mg of BST; the other six were injected with a control vehicle. Cows were maintained under standard dairy management during mid-winter for 30 days. Milk production was recorded twice daily, and blood samples were taken weekly. Animals were then transferred to environmentally controlled chambers and exposed to cycling thermoneutral (15° to 20° C) and cycling cold (-5° to +5° C) temperatures for 10 days in a split-reversal design. Milk production, feed and water intake, body weights and rectal temperatures were monitored. Blood samples were taken on days 1, 3, 5, 8 and 10 of each period and analyzed for plasma triiodothyronine (T3), thyroxine (T4), cortisol, insulin and prolactin. Under farm conditions, BST-treated cows produced 11% more milk than control-treated cows and in environmentally controlled chambers produced 17.4% more milk. No differences due to BST in feed or water intake, body weights or rectal temperatures were found under laboratory conditions. Plasma T3 and insulin increased due to BST treatment while no effect was found on cortisol, prolactin or T4. The results showed that the benefits of BST supplementation in lactating dairy cows were achieved under cold environmental conditions.

Becker, B. A.; Johnson, H. D.; Li, R.; Collier, R. J.

1990-09-01

259

Laboratory-scale interaction between CO2-rich brine and limestone and sandstone under supercritical CO2 conditions  

NASA Astrophysics Data System (ADS)

A test site for a prospective CO2 geological storage is situated in Hontomín (Burgos, northern Spain) with a reservoir rock that is composed of limestone (calcite) and sandstone (66 wt.% calcite, 28 wt.% quartz and 6 wt.% microcline). During and after CO2 injection, the resulting CO2-rich acid brine will likely promote the dissolution of carbonate minerals (calcite) and aluminosilicates (microcline). Since the reservoir Hontomín brine contains sulfate, gypsum (or anhydrite at depth) may precipitate. These coupled dissolution and precipitation reactions may induce changes in porosity and pore structure of the repository rocks. Percolations experiments with mechanically fractured cores (8.6 mm in diameter and 18 mm length) were performed under CO2 supercritical conditions (Pfluid = 150 bar; pCO2 ? 90 bar and T = 60 ºC) in order to evaluate and quantify variations in fracture permeability, preferential path formation and fracture volume. The brine sulfate content and the flow rate were varied. Regarding limestone, as the synthetic brines circulated through the fracture, the fracture permeability initially increased slowly, to thereafter increase rapidly. This change was due to a localized dissolution process (wormhole formation) along the core that occurred regardless gypsum precipitation. Nonetheless, the originated fracture volume in the sulfate-rich brine experiments was a factor of two smaller than that in sulfate-free brine experiments. Also, an increase in flow rate from 0.2 to 60 mL/h increased the volume of both dissolved calcite and precipitated gypsum. Regarding sandstone, permeability increased gradually with time. Nonetheless, this increase was not always continuous due to eventual fracture clogging. Formation of wormholes was observed. Acknowledgements This study was financed by CIUDEN (Ciudad de la Energía), the Compostilla OXYCFB300 project and the PANACEA project (European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement number 282900).

Garcia-Rios, Maria; Cama, Jordi; Luquot, Linda; Soler, Josep

2014-05-01

260

Life history of Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) fed with castor bean (Ricinus communis L.) pollen in laboratory conditions.  

PubMed

The predatory mite, Neoseiulus californicus (McGregor, 1954) (Acari: Phytoseiidae) is one of the principal natural enemies of tetranychid mites in several countries, promoting efficient control of those mites in several food and ornamental crops. Pest attacks such as that of the spider mite, Tetranychus urticae Koch, 1836 (Acari: Tetranychidae), is one of the problems faced by farmers, especially in the greenhouse, due to the difficulty of its control with the use of chemicals because of the development of fast resistance making it hard to control it. The objective of this work was to study the life history of the predatory mite N. californicus as a contribution to its mass laboratory rearing, having castor bean plant [Ricinus communis L. (Euphorbiaceae)] pollen as food, for its subsequent use as a natural enemy of T. urticae on a cultivation of greenhouse rosebushes. The studies were carried out in the laboratory, at 25 ± 2°C of temperature, 70 ± 10% RH and a 14 hour photophase. The biological aspects and the fertility life table were appraised. Longevity of 32.9 days was verified for adult females and 40.4 days for males. The intrinsic rate of increase (rm) was 0.2 and the mean generation time (T) was 17.2 days. The population doubled every 4.1 days. The results obtained were similar to those in which the predatory mite N. californicus fed on T. urticae. PMID:25296220

Marafeli, Pp; Reis, Pr; Silveira, Ec da; Souza-Pimentel, Gc; Toledo, Ma de

2014-08-01

261

Laboratory and modeling studies on the effects of water and soot emissions and ambient conditions on the formation of contrail ice particles in the jet regime  

NASA Astrophysics Data System (ADS)

Contrails and contrail-induced cirrus clouds are identified as the most uncertain components in determining aviation impacts on global climate change. Parameters affecting contrail ice particle formation immediately after engine exit plane (<5 s in plume age) may be critical to ice particle properties used in large scale models predicting contrail radiative forcing. Despite this, detailed understanding of these parametric effects is still limited. In this paper, we present results from recent laboratory and modeling studies conducted to investigate the effects of water and soot emissions and ambient conditions on the near-field formation of contrail ice particles. The Particle Aerosol Laboratory (PAL) at the NASA Glenn Research Center and the Aerodyne microphysical parcel model for contrail ice particle formation were employed. Our studies show that exhaust water concentrations have a significant impact on contrail ice particle formation. When soot was introduced, ice particle formation was observed only when exhaust water concentration was above a critical level. When no soot or sulfuric acid was introduced, homogeneous ice particle formation was unfavorable. Soot particles were found to compete for water vapor condensation, and higher soot concentrations emitted into the chamber resulted in smaller ice particles being formed. Chamber conditions corresponding to higher altitude standard day conditions were found to favor ice particle formation as expected. The microphysical model captures experimental trends well, but discrepancies between the model and the experiments exist as the model predicts narrower ice particle size distributions and ice particle sizes nearly a factor of two larger than measured. These discrepancies are likely due to the lack of treatment of turbulent mixing in the model and particle loss and scatter during the experimental sampling process. Future measurement activities are planned to investigate other important parameters, such as soot surface properties and sulfuric acid concentrations, using the PAL and microphysical model.

Wong, H.-W.; Beyersdorf, A. J.; Heath, C. M.; Ziemba, L. D.; Winstead, E. L.; Thornhill, K. L.; Tacina, K. M.; Ross, R. C.; Albo, S. E.; Bulzan, D. L.; Anderson, B. E.; Miake-Lye, R. C.

2011-09-01

262

Accuracy of uploadable pedometers in laboratory, overground, and free-living conditions in young and older adults  

PubMed Central

Purpose The purpose of this study was to examine the accuracy of uploadable pedometers to accurately count steps during treadmill (TM) and overground (OG) walking, and during a 24 hour monitoring period (24 hr) under free living conditions in young and older adults. Methods One hundred and two participants (n=53 aged 20–49 yrs; n=49 aged 50–80 yrs) completed a TM protocol (53.6, 67.0, 80.4, 93.8, and 107.2 m/min, five minutes for each speed) and an OG walking protocol (self-determined “< normal”, “normal”, and “> normal” walking speeds) while wearing two waist-mounted uploadable pedometers (Omron HJ-720ITC [OM] and Kenz Lifecorder EX [LC]). Actual steps were manually tallied by a researcher. During the 24 hr period, participants wore a New Lifestyles-1000 (NL) pedometer (standard of care) attached to a belt at waist level over the midline of the left thigh, in addition to the LC on the belt over the midline of the right thigh. The following day, the same procedure was conducted, replacing the LC with the OM. One-sample t-tests were performed to compare measured and manually tallied steps during the TM and OG protocols, and between steps quantified by the NL with that of the OM and LC during the 24 hr period. Mean error step scores (MES, criterion – device) and 95% Limits of Agreement (LoA) were calculated. Results There were no significant differences between the OM and tallied steps for any of the TM speeds for either the young or older adult groups. The LC significantly underestimated steps for the young adult group during the 53.6 m/min TM speed (MES 31.4 [14.5, 48.3]) and during the OG < normal walking speed (MES 12.0 [0.9, 23.1] (p<0.01 for both age groups). The LC also significantly underestimated steps for the older adult group during the TM speeds of 53.6 m/min (MES 64.5 [45.6, 83.4]), 67.0 m/min (MES 15.1 [6.1, 24.0]), and 80.4 m/min (MES 3.2 [0.6, 5.9]) (p<0.01 for all speeds), in addition to the OG < normal walking speed (MES 14.7 [?13.3, 42.6] (p<0.01). The OM reported significantly lower steps during the 24 hr period for the young adult group by 949.1 steps (t=6.111, p<0.025) and for the older adult group by 612.9 steps (t=2.397, p<0.025). Conclusion Both the OM and LC pedometers were more accurate as TM and OG walking speed increased. The OM significantly underestimated steps during the 24 hr compared with a standard of care evaluation. Overall, both uploadable pedometers appear acceptable to use in young or old age groups to measure walking behavior. PMID:23232036

2012-01-01

263

The Google Similarity Distance  

Microsoft Academic Search

Words and phrases acquire meaning from the way they are used in society, from their relative semantics to other words and phrases. For computers the equivalent of 'society' is 'database,' and the equivalent of 'use' is 'way to search the database.' We present a new theory of similarity between words and phrases based on information distance and Kolmogorov complexity. To

Rudi L. Cilibrasi; Paul M. B. Vitányi

2007-01-01

264

Evolutionary Similarity Among Genes  

Microsoft Academic Search

An evolutionary history of a set of organisms is a family tree, or topology, with branches of various lengths between vertices that describe how closely the organisms are related to each other. We consider the K evolutionary histories of K genes from a set of N organisms. Evolutionary similarity (ES) occurs when the branching patterns and relative branch lengths in

Marc A. Suchard; Robert E. Weiss; Janet S. Sinsheimer; Karin S. Dorman; Megha Patel; Edward R. B. McCabe

2003-01-01

265

Susceptibility of Culicoides species biting midges to deltamethrin-treated nets as determined under laboratory and field conditions in the Balearic Islands, Spain.  

PubMed

Culicoides Latreille (Diptera: Ceratopogonidae) are vectors of several arboviruses, including bluetongue virus (BTV) and African horse sickness virus (AHSV), which cause diseases in, respectively, sheep and cattle, and horses, and have economic repercussions mainly as a result of trade restrictions. Insecticides can be used to reduce vector populations and hence the spread of disease. Despite the economic importance of these diseases, relatively few studies have evaluated the efficacy of commercially available insecticides and the effectiveness of treated nets against Culicoides species. The aim of the present study was to evaluate the insecticidal effect of commercially available polyethylene nets (ZeroVector(®) ) treated with deltamethrin (4.4?g/kg?±?15%) on Culicoides species. Laboratory and field trials were conducted in Culicoides populations collected in Majorca in the Balearic Islands, Spain. The present study shows that deltamethrin-treated nets provoke high and rapid mortality (90-100%) in Culicoides midges under laboratory conditions and increase mortality by 13% when deployed in the field. PMID:24890642

Del Río, R; Barceló, C; Paredes-Esquivel, C; Lucientes, J; Miranda, M A

2014-12-01

266

Wirtanen At 3au An Experimental Program In The Laboratory Under Simulated Space-conditions, Accompanying The Rosetta Space-mission  

NASA Astrophysics Data System (ADS)

Simulated Space-Conditions in an earth laboratory, e.g. in a specially designed vacuum chamber with an adjusted insolation source cannot only support the development and qualification of space mission experiment hardware, but also an "in situ" investigation of the surface-near planetary phenomena. This was already demonstrated in the comet simulation program KOSI, performed in the DLR Space Simulator from 1986 to 1993 after the successful GIOTTO Space Mission to Comet P´Halley in 1986. The results of the simulation experiments have been helpful in understanding the recorded phenomena. Based on the experiences gathered in KOSI, we are now facing the ROSETTA space mission to Comet P´Wirtanen in 2003 with an extremely long hibernation phase till 2011. At this time the ROSETTA spacecraft will meet the cometary nucleus. Laboratory Experiments with different cometary analogous materials (CAM) and with different insolation periods will be performed in the DLR-PLANETARY SIMULATION FACILITY. This chamber, automatically cooled by liquid nitrogen (77K) has an internal space for experiments of 1.5m in diameter and 1.8m in height. Gas-dust interaction phenomena, and the thermal behaviour can be studied as well as the crustal and mantle formation and the structural change of the CAM by sintering and recondensation. We invite colleagues to join this program with ideas, models and hardware.

Kochan, H.; Richter, L.; Möhlmann, D.; Drescher, J.; Seidensticker, K. J.; Tokano, T.

267

High-resolution monitoring of root water uptake dynamics in laboratory conditions using full-wave inversion of near-field radar  

NASA Astrophysics Data System (ADS)

Root water uptake dynamics at local scale can be studied in laboratory conditions by growing plants in rhizotron containing sand and by imaging the water content evolution of the medium using light transmission. This technique allows to retrieve the water content with high resolution but cannot be applied in opaque media such as leaf-mold or clay, which is a major limitation for more realistic applications. Recently, ground-penetrating radar (GPR) has proven to be one of the most promising techniques for high-resolution digital soil mapping at the field scale. Particularly, by using full-wave inverse modeling of near-field GPR data with a high frequency antenna, the electrical properties of soil and their correlated water content can be reconstructed with a high spatiotemporal resolution. In this study, we applied the approach by using an ultra-wideband frequency-domain radar with a transmitting and receiving horn antenna operating in the frequency range 3-6 GHz for imaging, in near-field conditions, a rhizotron containing sand subject to different water content conditions. Synthetic radar data were also generated to examine the well-posedness of the full-waveform inverse problem at high frequencies. Finally, we compared the water content obtained by GPR and light transmission measurements. The results have shown that the near-field modeled and measured GPR data match very well in the frequency and time domains for both dry and wet sands. In the case of the dry sand, the estimated water content based on GPR and light transmission data was retrieved with small differences. This research shows the potential of the GPR system and near-field full-wave antenna-medium model to accurately estimate the water content of soils with a high spatial resolution. Future studies will focus on the use of GPR to monitor root water uptake dynamics of plants in field conditions. This abstract is of interest for COST Action TU1208.

Mourmeaux, Nicolas; Meunier, Félicien; Tran, Phuong Anh; Draye, Xavier; Lambot, Sébastien

2014-05-01

268

Laboratory and field studies on BTEX biodegradation in a fuel-contaminated aquifer under denitrifying conditions. Book chapter, May 88-Dec 92  

SciTech Connect

Leaking underground storage tanks are a major source of groundwater contamination by petroleum hydrocarbons. Of the approximately 1.4 million underground tanks storing gasoline in the United States, some petroleum experts estimate that 75,000 to 100,000 are leaking (Feliciano 1984). Gasoline and other fuels contain benzene, toluene, ethylbenzene, and xylenes (collectively known as BTEX), which are hazardous compounds regulated by the U.S. Environmental Protection Agency (EPA 1977). Laboratory studies were conducted in conjunction with a field demonstration project on nitrate-mediated biorestoration of a fuel-contaminated aquifer at a U.S. Coast Guard facility in Traverse City, MI. Microcosms were prepared under either aerobic or strictly anaerobic, denitrifying conditions using core samples aseptically obtained from the aquifer. The microcosms were spiked with aromatic hydrocarbons (BTEX) and incubated as 12 C. Virtually all of the aromatic hydrocarbons, including benzene, were degraded to below detection limits within seven days under aerobic conditions, although o-xylene was somewhat more recalcitrant. Under denitrifying conditions, toluene, ethylbenzene, m-xylene, and 1,2,4-trimethylbenzene were also degraded to below detection limits, although this occurred between two to three weeks. o-Xylene was only slowly degraded and benzene was recalcitrant under denitrifying conditions. In the field demonstration project, an infiltration gallery was used to recirculate water at a rate sufficient to create a water table mound encompassing the contaminated interval. After hydraulic equilbrium was achieved nitrate and nutrients were added to the recharge water. Benzene removal occurred before nitrate addition; mass balances indicated that sufficient oxygen was recirculated to account for complete biodegradation aerobically.

Hutchins, S.R.; Wilson, J.T.

1991-01-01

269

Racism and Sexism: Similarities.  

ERIC Educational Resources Information Center

Criticizes racism and sexism. Women and ethnic minority men face incongenial conditions when working in organizations dominated by White males. Understanding the treatment accorded women and ethnic minority men may facilitate the spread of democracy to include these latter groups and lead to a concerted attack on racism and sexism. (Author/BEF)

Schetlin, Elanor M.

1979-01-01

270

NCBI More Information: Similarity  

NSDL National Science Digital Library

This page summarizes the basic concept and vocabulary of sequence similarity searching. It is included for those new to the field who may not appreciate the importance of this technique in biology, who lack the vocabulary to understand the BLAST guide and tutorial or who require a basic rather than a sophisticated understanding of the methods involved. Sections include introduction, premise, terms, general approach, the BLAST algorithm, quantification, gaps, significance, and databases. Users can link to BLAST, BLAST tutorial, and additional BLAST information from this page.

Information, National C.

271

A Laboratory Test Setup for in Situ Measurements of the Dielectric Properties of Catalyst Powder Samples under Reaction Conditions by Microwave Cavity Perturbation: Set up and Initial Tests  

PubMed Central

The catalytic behavior of zeolite catalysts for the ammonia-based selective catalytic reduction (SCR) of nitrogen oxides (NOX) depends strongly on the type of zeolite material. An essential precondition for SCR is a previous ammonia gas adsorption that occurs on acidic sites of the zeolite. In order to understand and develop SCR active materials, it is crucial to know the amount of sorbed ammonia under reaction conditions. To support classical temperature-programmed desorption (TPD) experiments, a correlation of the dielectric properties with the catalytic properties and the ammonia sorption under reaction conditions appears promising. In this work, a laboratory test setup, which enables direct measurements of the dielectric properties of catalytic powder samples under a defined gas atmosphere and temperature by microwave cavity perturbation, has been developed. Based on previous investigations and computational simulations, a resonator cavity and a heating system were designed, installed and characterized. The resonator cavity is designed to operate in its TM010 mode at 1.2 GHz. The first measurement of the ammonia loading of an H-ZSM-5 zeolite confirmed the operating performance of the test setup at constant temperatures of up to 300 °C. It showed how both real and imaginary parts of the relative complex permittivity are strongly correlated with the mass of stored ammonia. PMID:25211199

Dietrich, Markus; Rauch, Dieter; Porch, Adrian; Moos, Ralf

2014-01-01

272

Laboratory Buildings.  

ERIC Educational Resources Information Center

The need for flexibility in science research facilities is discussed, with emphasis on the effect of that need on the design of laboratories. The relationship of office space, bench space, and special equipment areas, and the location and distribution of piping and air conditioning, are considered particularly important. This building type study…

Barnett, Jonathan

273

Laboratory Astrochemistry: Interstellar PAHs  

NASA Technical Reports Server (NTRS)

Polycyclic aromatic hydrocarbons (PAHs) are now considered to be an important and ubiquitous component of the organic material in space. PAHs are found in a large variety of extraterrestrial materials such as interplanetary dust particles (IDPs) and meteoritic materials. PAHs are also good candidates to account for the infrared emission bands (UIRs) and the diffuse interstellar optical absorption bands (DIBs) detected in various regions of the interstellar medium. The recent observations made with the Infrared Space Observatory (ISO) have confirmed the ubiquitous nature of the UIR bands and their carriers. PAHs are thought to form through chemical reactions in the outflow from carbon-rich stars in a process similar to soot formation. Once injected in the interstellar medium, PAHs are further processed by the interstellar radiation field, interstellar shocks and energetic particles. A major, dedicated, laboratory effort has been undertaken to measure the physical and chemical characteristics of these complex molecules and their ions under experimental conditions that mimic the interstellar conditions. These measurements require collision-free conditions where the molecules and ions are cold and chemically isolated. The spectroscopy of PAHs under controlled conditions represents an essential diagnostic tool to study the evolution of extraterrestrial PAHs. The Astrochemistry Laboratory program will be discussed through its multiple aspects: (1) objectives, (2) approach and techniques adopted, (3) adaptability to the nature of the problem(s), and (4) results and implications for astronomy as well as for molecular spectroscopy. A review of the data generated through laboratory simulations of space environments and the role these data have played in our current understanding of the properties of interstellar PAHs will be presented. The discussion will also introduce the newest generation of laboratory experiments that are currently being developed in order to provide a closer simulation of space environments and a better support to space missions.

Salama, Farid; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

274

Effect of ectoparasitic Pimeliaphilus plumifer mites (Acari: Pterygosomatidae) on Meccus pallidipennis (Hemiptera: Reduviidae) and several other Chagas' disease vectors under laboratory conditions.  

PubMed

Several biological parameters were evaluated to determine the capacity of Pimeliaphilus plumifer as biological control agent of Triatominae bugs. When P. plumifer and bugs of a variety of triatomine species were forced together in cages in the laboratory, the incidence of mite infestation was the following: Meccus pallidipennis > M. bassolsae > Triatoma rubida > M. longipennis > M. picturatus, and practically no mites were found on T. infestans and Rhodnius prolixus. Adults and hexapod larvae of P. plumifer were the only stages found to parasitize on M. pallidipennis. Fourth and fifth instar nymphs of this bug appeared most susceptible to mite infestation. P. plumifer mites located preferably on the coxae, ventral abdomen and pronotum of M. pallidipennis bugs. The number of blood meals, amount of ingested blood, and resistance to starvation of M. pallidipennis were similar in both the control and the mite infested groups. On the other hand, mite infection reduced molting rate in nymphs and longevity in adults, increased mortality in third-fifth instar nymphs, and fewer viable eggs were laid by females infected with P. plumifer. These effects could be related with nutritional deficiencies. Our results support the use of P. plumifer mites as control agents of host Triatominae species. PMID:17549587

Martinez-Sanchez, Abisai; Camacho, Alejandro D; Quintero-Martinez, Maria Teresa; Alejandre-Aguilar, Ricardo

2007-01-01

275

Laboratory and modeling studies on the effects of water and soot emissions and ambient conditions on the properties of contrail ice particles in the jet regime  

NASA Astrophysics Data System (ADS)

Contrails and contrail-induced cirrus clouds are identified as the most uncertain components in determining aviation impacts on global climate change. Parameters affecting contrail ice particle formation immediately after the engine exit plane (< 5 s in plume age) may be critical to ice particle properties used in large-scale models predicting contrail radiative forcing. Despite this, detailed understanding of these parametric effects is still limited. In this paper, we present results from recent laboratory and modeling studies conducted to investigate the effects of water and soot emissions and ambient conditions on near-field formation of contrail ice particles and ice particle properties. The Particle Aerosol Laboratory (PAL) at the NASA Glenn Research Center and the Aerodyne microphysical parcel model for contrail ice particle formation were employed. Our studies show that exhaust water concentration has a significant impact on contrail ice particle formation and properties. When soot particles were introduced, ice particle formation was observed only when exhaust water concentration was above a critical level. When no soot or sulfuric acid was introduced, no ice particle formation was observed, suggesting that ice particle formation from homogeneous nucleation followed by homogeneous freezing of liquid water was unfavorable. Soot particles were found to compete for water vapor condensation, and higher soot concentrations emitted into the chamber resulted in smaller ice particles being formed. Chamber conditions corresponding to higher cruising altitudes were found to favor ice particle formation. The microphysical model captures trends of particle extinction measurements well, but discrepancies between the model and the optical particle counter measurements exist as the model predicts narrower ice particle size distributions and ice particle sizes nearly a factor of two larger than measured. These discrepancies are likely due to particle loss and scatter during the experimental sampling process and the lack of treatment of turbulent mixing in the model. Our combined experimental and modeling work demonstrates that formation of contrail ice particles can be reproduced in the NASA PAL facility, and the parametric understanding of the ice particle properties from the model and experiments can potentially be used in large-scale models to provide better estimates of the impact of aviation contrails on climate change.

Wong, H.-W.; Beyersdorf, A. J.; Heath, C. M.; Ziemba, L. D.; Winstead, E. L.; Thornhill, K. L.; Tacina, K. M.; Ross, R. C.; Albo, S. E.; Bulzan, D. L.; Anderson, B. E.; Miake-Lye, R. C.

2013-10-01

276

Laboratory and field-based calibration study for the use of freshwater bivalve shells as an archive of environmental and climatic conditions.  

NASA Astrophysics Data System (ADS)

The accretionary growth of mollusc shells makes it possible to obtain recordings of the life history of these organisms. Freshwater bivalves are common inhabitant of past and present rivers and lakes. The wide latitudinal distribution of the Unionidae allows their shells to be used as an archive of environmental variations. Physical and chemical record of the shells contains precious information on water temperature, rainfall or metal concentrations. We developed a coupled laboratory and field-based calibration study on freshwater bivalve shells to determine the ability to track water oxygen isotopes composition (?18Ow), dissolved metal and temperature changes at a decadal to infra-annual time scale. A genetically homogenous population of Anodonta cygnea and Corbicula fluminea have been cultured in the Seine River and in laboratory, under controlled conditions. Daily temperatures and semi-monthly ?18Ow and trace metals (Mn, Cu, Zn, Cd, As, Pb, …) were measured during the experiment. For the micro-sampling strategy, we have to establish a chronological time scale in the shell growth. Thus each month, an experimental 4 hours Mn2+ staining was performed to have a precise temporal marking during shell growth. Additionally, wild stocks of European and African Unionidae shells were analysed under microscopy and geochemical study. Mn2+ markings can be recognized under cathodoluminescence (CL) analysis of cross section along the growth axis of the shells. Their identification on the two distinct groups (in vivo and in vitro experiments) helps us to determine the cyclicity of the natural fluctuations of the luminescence and the shell growth rate. The counting of annual growth increments reveals a life span over ten years, but micro-CL rhythms are also identified. This sclerochronologic approach is used to confront water physico-chemical changes with the biogenic carbonate geochemical records. First results show a latitudinal gradient (from France to South Africa) of ?18O and ?13C shells in respect with the climatic conditions (temperature and humidity). This study contributes to fixe the interest of freshwater bivalve shells analyses for hydrological management (i.e. tracking of natural or anthropogenic dissolved metal pollution) as well as (paleo)climatic investigations.

Lartaud, F.; Le Callonnec, L.; de Rafelis, M.; Emmanuel, L.; Missang, E.; Castrec-Rouelle, M.; Mouchel, J. M.; Segalen, L.

2009-04-01

277

Measuring Total Flux of Organic Vapors From the Unsaturated Zone Under Natural Conditions: Design, Laboratory and Field Testing of a Flux Chamber Device  

NASA Astrophysics Data System (ADS)

A simple, easy-to-use, and inexpensive device for measuring VOC flux under natural conditions was designed and tested both in a controlled laboratory environment and in a natural field setting. The chamber consists of a stainless-steel right circular cylinder open on one end with a flexible, impermeable membrane allowing for chamber expansion and contraction. Air is pumped from inside the chamber through activated carbon traps and returned to the chamber maintaining a net zero pressure gradient from the inside to the outside of the chamber. The traps are analyzed using thermal desorption/GC-FID and the mass of contaminant is divided by the product of the sampled area and sample time to give VOC flux measured by the chamber. Design parameters for the chamber were selected using continuously stirred tank reactor (CSTR)-equation based modeling under step, sinusoidal and transport-model simulation flux inputs. Laboratory testing of the flux chamber under both diffusion and advection dominated conditions was performed in a device constructed to simulate unsaturated zone transport. Aqueous trichloroethene (TCE) solution was pumped through the bottom of a steel drum inside which 50-cm of fine sand was suspended. For diffusion-dominated transport experiments, the chamber was installed in the sand at the top of the simulator and operated in the same manner as would occur in the field. The flux measurement of the chamber was then compared to flux prediction based on measured linear concentration data from the simulator and Fick's law. Advective transport is initiated in the vadose zone simulator by flowing humidified, pressurized air into an input port in the bottom of the simulator below the suspended porous media. Soil-gas velocity is calculated by dividing the airflow input by the surface area of the simulator. Flux was measured with the chamber and compared to flux predicted using airflow and concentration data from the simulator. Results from both the diffusion-only and combined advection/diffusion tests indicate the chamber device performs well under a wide range of fluxes. Additionally, results of side-by-side testing of three chamber devices at a TCE-contaminated field site are presented.

Tillman, F. D.; Choi, J.; Smith, J. A.

2002-05-01

278

Prediction of Meteorological Conditions for the Mars Science Laboratory Rover Curiosity and comparisons with the Rover Environmental Monitoring Station (REMS) measurements  

NASA Astrophysics Data System (ADS)

The Mars Regional Atmospheric Modeling System (MRAMS) is applied to the Gale Crater region, the landing site of the Mars Science Laboratory (MSL) Rover Curiosity. The landing site within Gale Crater is at one of the lowest elevation locations between the crater rim and the ~4 km high central mound known as Mt. Sharp. As Curiosity heads toward its long term target of Mt. Sharp, the meteorological conditions are expected to change due to the increasing influence of topographically-induced thermal circulations that have been predicted by numerous previous studies [1, 2 ,3, 4]. For the first time ever, these mesoscale model predictions of slope flows can be validated against the meteorological data that is currently being collected by the Rover Environmental Monitoring Station (REMS) [5]. We first provide a comparison of MRAMS predictions (pressure, temperature, winds, and ground temperature) to the REMS data available near the season of landing (~LS 150-200) in order to provide a baseline of model performance, and then we provide predictions of the meteorological conditions as a function of season and expected location of the rover as a function of time. Acknowledgements: JP-G and FJM-T are supported by Economy and Competitivity Ministry (AYA2011-25720). S. R. is supported by the MSL Project at JPL. References: [1] Rafkin, S. C. R., and T. I. Michaels (2003), J. Geophys. Res., 108(E12), 8091. [2] Michaels, T. I., and S. C. R. Rafkin (2008), J. Geophys. Res.-Planets, 113. [3] Toigo, A. D., and M. I. Richardson (2003), J. Geophys. Res., 108(E12), 8092. [4] Tyler, D., J. R. Barnes, and E. D. Skyllingstad (2008), J. Geophys. Res.-Planets, 113(E8). [5] Gómez-Elvira, J., et al. (2012), Space Science Reviews, 170(1-4), 583-640.

Pla-García, Jorge; Rafkin, Scot; Martín-Torres, Javier; Elvira-Gómez, Javier; Lepinette, Alain; Kahanpää, Henrik; Rodríguez-Manfredi, Jose; Navarro, Sara; Sebastián, Eduardo

2013-04-01

279

Similarities in Acute Temperature Preferences of Freshwater Fishes  

Microsoft Academic Search

A statistical analysis of new and published laboratory data revealed strong geographic similarities in acute (up to 4-hour) temperature preferences for several freshwater fishes. Regression models developed from our laboratory studies predicted acute temperature preferences of species from other geographic areas. Species within a family (three cyprinids, two ictalurids, and six centrarchids were tested) have similar acute preferenda, except that

Dilip Mathur; Robert M. Schutsky; Edmund J. Purdy Jr; Carl A. Silver

1981-01-01

280

Similarities in acute temperature preferences of freshwater fishes  

Microsoft Academic Search

A statistical analysis of new and published laboratory data revealed strong geographic similarities in acute (up to 4-h) temperature preferences for several freshwater fishes. Regression models developed from our laboratory studies predicted acute temperature preferences of species from other geographic areas. Species within a family (three cyprinids, two ictalurids, and six centrarchids were tested) have similar acute preferenda, except that

DILIP MATHUR; ROBERT M. SCHUTSKY; EDMUND J. PURDY; CARL A. SILVER

1981-01-01

281

Manganese and trace-metal mobility under reducing conditions following in situ oxidation of TCE by KMnO4: a laboratory column experiment.  

PubMed

The stability of Mn oxides, and the potential for mobilization of associated trace metals, were assessed by simulating the onset of microbially-mediated reducing conditions in a continuous-flow column experiment. The column had previously been used for an in situ chemical oxidation (ISCO) experiment in which trichloroethylene was reacted with permanganate in the presence of aqueous trace metals, which produced Mn oxyhydroxides (MnO(x)) that sequestered the trace metals and coated the column sand. The column influent solution represented the incursion of ambient groundwater containing dissolved organic carbon (DOC) into an ISCO treatment zone. The influx of DOC-containing groundwater initiated a series of cation-exchange, surface-complexation and reductive-dissolution reactions that controlled the release of aqueous metals from the system. Peak concentrations in the effluent occurred in the order Na, Mo, Cr, Zn, K, Mn, Fe, Pb, Mg, Ni, Cu and Ca. Manganese release from the column was controlled by a combination of cation exchange, reductive dissolution and precipitation of rhodochrosite. The trend in Fe concentrations was similar to that of Mn, and also resulted from a combination of reductive dissolution and cation exchange. Cation exchange and/or surface-complexation were the primary mechanisms controlling Cu, Ni, Mo and Pb release to solution, while Zn and Cr concentrations did not display coherent trends. Although metal release from the treatment zone was evident in the data, concentrations of trace metals remained below 0.05 mg L(-1) with the exception of Mo which reached concentrations on the order of 1 mg L(-1). The establishment of anaerobic conditions in ISCO-treated aquifers may result in a prolonged flux of aqueous Mn(II), but with the exception of MoO(4)(2-), it is unlikely that trace metals sequestered with MnO(x) during ISCO will be released to the groundwater in elevated concentrations. PMID:20889229

Loomer, Diana B; Al, Tom A; Banks, Vernon J; Parker, Beth L; Mayer, K Ulrich

2011-01-25

282

Progress in inertial confinement fusion at Lawrence Livermore National Laboratory  

Microsoft Academic Search

The goals of the Inertial Fusion Program at the Lawrence Livermore National Laboratory are to study matter under extreme conditions of temperature and pressure and to produce fusion energy from inertially confined fusion fuel. With the conclusion of multi-kilojoule 0.53 micron experiments on Novette, vastly improved plasma conditions were demonstrated compared to those previously obtained at LLNL with similar energies

J. F. Holzrichter

1984-01-01

283

Bt-toxin uptake by the non-target herbivore, Myzus persicae (Hemiptera: Aphididae), feeding on transgenic oilseed rape in laboratory conditions.  

PubMed

The potential non-target effects of genetically modified crops are some of the more debated topics within applied biotechnologies in agriculture and environmental risk assessment. The objective of the present research was to study the potential Bt-toxin uptake by the non-target herbivore Myzus persicae Sulzer (Hemiptera: Aphididae) feeding on transgenic oilseed rape plants (Brassica napus cv. 'Westar' lines GT 2-4) expressing the Cry1Ac endotoxin. A specific aim was to replicate our previous experiment in controlled laboratory conditions to avoid or minimize the risk of contamination leading to potential false positive results. The toxin levels in vernalized (V) and not-vernalized (not-V) transgenic oilseed rape plants was also monitored to better clarify the role of physiological processes on Bt-toxin expression. Cry1Ac expression in not-V plants (mean concentration±SE=167.8±5.7 ?g kg-1 FW) showed a pattern of large variability, in comparison with V plants whose expression (mean concentration±SE=227.7±1.9 ?g kg-1 FW) was significantly more stable. Cry1Ac toxin was detected in three aphid samples reared on V plants with a mean toxin concentration±SE of 4.8±0.6 ?g Kg-1 FW and in three out of six samples of aphids reared on not-V plants (mean toxin concentration±SE=7.1±1.2 ?g kg-1 FW). The mean Bt-toxin concentration of all the positive aphid samples was 5.9±1.0 ?g kg-1 FW. Our results confirmed the findings of our previous experiment and highlighted the potential for Cry1Ac toxin uptake by aphids feeding on transgenic oilseed rape plants. PMID:21034523

Burgio, G; Dinelli, G; Marotti, I; Zurla, M; Bosi, S; Lanzoni, A

2011-04-01

284

Self-Similar Modes of Coherent Diffusion  

E-print Network

Self-similar solutions of the coherent diffusion equation are derived and measured. The set of real similarity solutions is generalized by the introduction of a nonuniform phase surface, based on the elegant Gaussian modes of optical diffraction. In an experiment of light storage in a gas of diffusing atoms, a complex initial condition is imprinted, and its diffusion dynamics is monitored. The self-similarity of both the amplitude and the phase pattern is demonstrated, and an algebraic decay associated with the mode order is measured. Notably, as opposed to a regular diffusion spreading, a self-similar contraction of a special subset of the solutions is predicted and observed.

O. Firstenberg; P. London; D. Yankelev; R. Pugatch; M. Shuker; N. Davidson

2010-08-16

285

Impact of the addition of different plant residues on carbon-nitrogen content and nitrogen mineralization-immobilization turnover in a soil incubated under laboratory conditions  

NASA Astrophysics Data System (ADS)

Application of plant residues as soil amendment may represent a valuable recycling strategy that affects on carbon (C) and nitrogen (N) cycling, soil properties improvement and plant growth promotion. The amount and rate of nutrient release from plant residues depend on their quality characteristics and biochemical composition. A laboratory incubation experiment was conducted for 120 days under controlled conditions (25 °C and 58% water filled pore space (WFPS)) to quantify initial biochemical composition and N mineralization of leguminous and non-leguminous plant residues i.e. the roots, shoots and leaves of Glycine max, Trifolium repens, Zea mays, Poplus euramericana, Rubinia pseudoacacia and Elagnus umbellate incorporated into the soil at the rate of 200 mg residue N kg-1 soil. The diverse plant residues showed wide variation in total N, carbon, lignin, polyphenols and C/N ratio with higher polyphenol content in the leaves and higher lignin content in the roots. The shoot of G. max and the shoot and root of T. repens displayed continuous mineralization by releasing a maximum of 109.8, 74.8 and 72.5 mg N kg-1 and representing a 55, 37 and 36% of added N being released from these resources. The roots of G. max and Z. mays and the shoot of Z. mays showed continuous negative values throughout the incubation showing net immobilization. After an initial immobilization, leaves of P. euramericana, R. pseudoacacia and E. umbellate exhibited net mineralization by releasing a maximum of 31.8, 63.1 and 65.1 mg N kg-1, respectively and representing a 16, 32 and 33% of added N being released. Nitrogen mineralization from all the treatments was positively correlated with the initial residue N contents (r = 0.89; p ? 0.01), and negatively correlated with lignin content (r = -0.84; p ? 0.01), C/N ratio (r = -0.69; p ? 0.05), lignin/N ratio (r = -0.68; p ? 0.05), polyphenol/N ratio (r = -0.73; p ? 0.05) and ligin + polyphenol/N ratio (r = -0.70; p ? 0.05) indicating a significant role of residue chemical composition and quality in regulating N transformations and cycling in soil. The present study indicates that incorporation of plant residues strongly modify the mineralization-immobilization turnover (MIT) of soil that can be taken into account to develop synchronization between net N mineralization and crop demand in order to maximize N delivery and minimize N losses.

Abbasi, M. K.; Tahir, M. M.; Sabir, N.; Khurshid, M.

2014-10-01

286

Similarity increases altruistic punishment in humans  

PubMed Central

Humans are attracted to similar others. As a consequence, social networks are homogeneous in sociodemographic, intrapersonal, and other characteristics—a principle called homophily. Despite abundant evidence showing the importance of interpersonal similarity and homophily for human relationships, their behavioral correlates and cognitive foundations are poorly understood. Here, we show that perceived similarity substantially increases altruistic punishment, a key mechanism underlying human cooperation. We induced (dis)similarity perception by manipulating basic cognitive mechanisms in an economic cooperation game that included a punishment phase. We found that similarity-focused participants were more willing to punish others’ uncooperative behavior. This influence of similarity is not explained by group identity, which has the opposite effect on altruistic punishment. Our findings demonstrate that pure similarity promotes reciprocity in ways known to encourage cooperation. At the same time, the increased willingness to punish norm violations among similarity-focused participants provides a rationale for why similar people are more likely to build stable social relationships. Finally, our findings show that altruistic punishment is differentially involved in encouraging cooperation under pure similarity vs. in-group conditions. PMID:24218611

Mussweiler, Thomas; Ockenfels, Axel

2013-01-01

287

Complex Wavelet Structural Similarity: A New Image Similarity Index  

Microsoft Academic Search

We introduce a new measure of image similarity called the complex wavelet structural similarity (CW-SSIM) index and show its applicability as a general purpose image similarity index. The key idea behind CW-SSIM is that certain image distortions lead to consistent phase changes in the local wavelet coefficients, and that a consistent phase shift of the coefficients does not change the

Mehul P. Sampat; Zhou Wang; Shalini Gupta; Alan Conrad Bovik; Mia K. Markey

2009-01-01

288

Molecular similarity in medicinal chemistry.  

PubMed

Similarity is a subjective and multifaceted concept, regardless of whether compounds or any other objects are considered. Despite its intrinsically subjective nature, attempts to quantify the similarity of compounds have a long history in chemical informatics and drug discovery. Many computational methods employ similarity measures to identify new compounds for pharmaceutical research. However, chemoinformaticians and medicinal chemists typically perceive similarity in different ways. Similarity methods and numerical readouts of similarity calculations are probably among the most misunderstood computational approaches in medicinal chemistry. Herein, we evaluate different similarity concepts, highlight key aspects of molecular similarity analysis, and address some potential misunderstandings. In addition, a number of practical aspects concerning similarity calculations are discussed. PMID:24151987

Maggiora, Gerald; Vogt, Martin; Stumpfe, Dagmar; Bajorath, Jürgen

2014-04-24

289

Exploration Laboratory Analysis FY13  

NASA Technical Reports Server (NTRS)

The Exploration Laboratory Analysis (ELA) project supports the Exploration Medical Capability (ExMC) risk, which is stated as the Risk of Inability to Adequately Treat an Ill or Injured Crew Member, and ExMC Gap 4.05: Lack of minimally invasive in-flight laboratory capabilities with limited consumables required for diagnosing identified Exploration Medical Conditions. To mitigate this risk, the availability of inflight laboratory analysis instrumentation has been identified as an essential capability in future exploration missions. Mission architecture poses constraints on equipment and procedures that will be available to treat evidence-based medical conditions according to the Space Medicine Exploration Medical Conditions List (SMEMCL), and to perform human research studies on the International Space Station (ISS) that are supported by the Human Health and Countermeasures (HHC) element. Since there are significant similarities in the research and medical operational requirements, ELA hardware development has emerged as a joint effort between ExMC and HHC. In 2012, four significant accomplishments were achieved towards the development of exploration laboratory analysis for medical diagnostics. These achievements included (i) the development of high priority analytes for research and medical operations, (ii) the development of Level 1 functional requirements and concept of operations documentation, (iii) the selection and head-to-head competition of in-flight laboratory analysis instrumentation, and (iv) the phase one completion of the Small Business Innovation Research (SBIR) projects under the topic Smart Phone Driven Blood-Based Diagnostics. To utilize resources efficiently, the associated documentation and advanced technologies were integrated into a single ELA plan that encompasses ExMC and HHC development efforts. The requirements and high priority analytes was used in the selection of the four in-flight laboratory analysis performers. Based upon the competition results, a down select process will be performed in the upcoming year. Looking ahead, this unified effort has positioned each element for an in-flight lab analysis demonstration of select diagnostics measurements in the 2015 timeframe.

Krihak, Michael; Perusek, Gail P.; Fung, Paul P.; Shaw, Tianna, L.

2013-01-01

290

Learning task-specific similarity  

E-print Network

The right measure of similarity between examples is important in many areas of computer science. In particular it is a critical component in example-based learning methods. Similarity is commonly defined in terms of a ...

Shakhnarovich, Gregory

2006-01-01

291

Concepts of similarity in bioinformatics  

Microsoft Academic Search

The key problem of bioinformatics is the prediction of properties, such as structure or function, based on similarity This chapter reviews the concepts and tools of similarity analysis used in various fields of bioinformatics.

Vilmos ÁGOSTON; László KAJÁN; Oliviero CARUGO; Zoltán HEGEDÜS

292

Transformation and Alignment in Similarity  

ERIC Educational Resources Information Center

This paper contrasts two structural accounts of psychological similarity: structural alignment (SA) and Representational Distortion (RD). SA proposes that similarity is determined by how readily the structures of two objects can be brought into alignment; RD measures similarity by the complexity of the transformation that "distorts" one…

Hodgetts, Carl J.; Hahn, Ulrike; Chater, Nick

2009-01-01

293

Acoustic Similarity and Dichotic Listening.  

ERIC Educational Resources Information Center

An experiment tests conjectures that right ear advantage (REA) has an auditory origin in competition or interference between acoustically similar stimuli and that feature-sharing effect (FSE) has its origin in assignment of features of phonetically similar stimuli. No effect on the REA for acoustic similarity, and a clear effect of acoustic…

Benson, Peter

1978-01-01

294

Personalized recommendation with corrected similarity  

E-print Network

Personalized recommendation attracts a surge of interdisciplinary researches. Especially, similarity based methods in applications of real recommendation systems achieve great success. However, the computations of similarities are overestimated or underestimated outstandingly due to the defective strategy of unidirectional similarity estimation. In this paper, we solve this drawback by leveraging mutual correction of forward and backward similarity estimations, and propose a new personalized recommendation index, i.e., corrected similarity based inference (CSI). Through extensive experiments on four benchmark datasets, the results show a greater improvement of CSI in comparison with these mainstream baselines. And the detailed analysis is presented to unveil and understand the origin of such difference between CSI and mainstream indices.

Zhu, Xuzhen; Cai, Shimin

2014-01-01

295

The influence of some pesticides on soil microbial flora in relation to changes in nutrient level, rock phosphate solubilization and P release under laboratory conditions  

Microsoft Academic Search

Two soil types, loamy sand and sandy soils, were treated with atrazine, pyrethrin and a mixture of metobromuron and metolachor for eight weeks in the laboratory to determine the effect of the chemicals on soil microbial populations and their mineralization activities. The experiment was also aimed at evaluating the changes that occurred in soil nutrient levels as a result of

L. B. Taiwo; B. A. Oso

1997-01-01

296

Hydrologic conditions and distribution of selected radiochemical and chemical constituents in water, Snake River Plain aquifer, Idaho National Engineering Laboratory, Idaho, 1989 through 1991  

Microsoft Academic Search

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds and disposal wells at the Idaho National Engineering Laboratory (INEL) has affected water quality in the Snake River Plain aquifer. The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, maintains a continuous monitoring network at the INEL to determine hydrologic trends and to delineate the movement of

R. C. Bartholomay; B. R. Orr; M. J. Liszewski; R. G. Jensen

1995-01-01

297

A similar shot to the previous image, this photograph, looking ...  

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

A similar shot to the previous image, this photograph, looking northwest, provides a closer image of the brick penthouse and other devices - Department of Energy, Mound Facility, Electronics Laboratory Building (E Building), One Mound Road, Miamisburg, Montgomery County, OH

298

Interruption-similarity effects during discourse processing  

PubMed Central

We examined the effect of interruption on reading to determine if discourse processing is susceptible to similarity-based interference. Participants read pairs of passages, either one before the other (in the continuous condition) or with the sentences of the two passages interleaved (in the interruption condition). In addition, the similarity of the types of passages (narrative or expository) in a pair was manipulated. Performance was measured with self-paced reading time of the sentences and with accuracy in answering comprehension questions. In two experiments, interruption slowed the reading of text sentences; this effect of interruption was greatest when the interrupting text was of the same style as the primary text (an interruption-similarity effect). We discuss these results with respect to current models of the role of working memory in discourse processing. PMID:16938692

Ledoux, Kerry; Gordon, Peter C.

2006-01-01

299

Anatoxin-a concentration in Anabaena and Aphanizomenon under different environmental conditions and comparison of growth by toxic and non-toxic Anabaena -strains — a laboratory study  

Microsoft Academic Search

Anatoxin-a-concentration in cells ofAnabaena- andAphanizomenon-strains and in their growth media were studied in the laboratory in batch cultures at different temperatures, light fluxes, orthophosphate and nitrate concentrations and with different nitrogen sources for growth. Toxin concentrations were detected by HPLC. Also, the growth of the toxicAnabaena-strains was compared to that of a non-toxic one. The non-toxicAnabaena was never found to

Jarkko Rapala; Kaarina Sivonen; Raija Luukkainen; Seppo I. Niemelä

1993-01-01

300

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2011 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2011-10-01

301

42 CFR 493.1211 - Condition: Urinalysis.  

Code of Federal Regulations, 2011 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Urinalysis. If the laboratory provides services in the subspecialty of Urinalysis, the laboratory must meet the...

2011-10-01

302

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2013 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2013-10-01

303

42 CFR 493.1211 - Condition: Urinalysis.  

Code of Federal Regulations, 2010 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Urinalysis. If the laboratory provides services in the subspecialty of Urinalysis, the laboratory must meet the...

2010-10-01

304

42 CFR 493.1211 - Condition: Urinalysis.  

Code of Federal Regulations, 2012 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Urinalysis. If the laboratory provides services in the subspecialty of Urinalysis, the laboratory must meet the...

2012-10-01

305

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2012 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2012-10-01

306

42 CFR 493.1213 - Condition: Toxicology.  

Code of Federal Regulations, 2010 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Toxicology. If the laboratory provides services in the subspecialty of Toxicology, the laboratory must meet the...

2010-10-01

307

42 CFR 493.1211 - Condition: Urinalysis.  

Code of Federal Regulations, 2013 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing ...Condition: Urinalysis. If the laboratory provides services in the subspecialty of Urinalysis, the laboratory must meet the...

2013-10-01

308

Discuss Similarity Using Visual Intuition  

ERIC Educational Resources Information Center

The change in size from a smaller shape to a larger similar shape (or vice versa) is created through continuous proportional stretching or shrinking in every direction. Students cannot solve similarity tasks simply by iterating or partitioning a composed unit, strategies typically used on numerical proportional tasks. The transition to thinking…

Cox, Dana C.; Lo, Jane-Jane

2012-01-01

309

Multivariate Time Series Similarity Searching  

PubMed Central

Multivariate time series (MTS) datasets are very common in various financial, multimedia, and hydrological fields. In this paper, a dimension-combination method is proposed to search similar sequences for MTS. Firstly, the similarity of single-dimension series is calculated; then the overall similarity of the MTS is obtained by synthesizing each of the single-dimension similarity based on weighted BORDA voting method. The dimension-combination method could use the existing similarity searching method. Several experiments, which used the classification accuracy as a measure, were performed on six datasets from the UCI KDD Archive to validate the method. The results show the advantage of the approach compared to the traditional similarity measures, such as Euclidean distance (ED), cynamic time warping (DTW), point distribution (PD), PCA similarity factor (SPCA), and extended Frobenius norm (Eros), for MTS datasets in some ways. Our experiments also demonstrate that no measure can fit all datasets, and the proposed measure is a choice for similarity searches. PMID:24895665

Wang, Jimin; Zhu, Yuelong; Li, Shijin; Wan, Dingsheng; Zhang, Pengcheng

2014-01-01

310

Laboratory Astrochemistry: Interstellar PAH Analogs  

NASA Technical Reports Server (NTRS)

Polycyclic aromatic hydrocarbons (PAHs) are now considered to be an important and ubiquitous component of the organic material in space. PAHs are found in a large variety of extraterrestrial materials such as interplanetary dust particles (IDPs) and meteoritic materials. PAHs are also good candidates to account for the infrared emission bands (UIRs) and the diffuse interstellar optical absorption bands (DIBs) detected in various regions of the interstellar medium. The recent observations made with the Infrared Space Observatory (ISO) have confirmed the ubiquitous nature of the UIR bands and their carriers. PAHs are though to form through chemical reactions in the outflow from carbon-rich stars in a process similar to soot formation. Once injected in the interstellar medium, PAHs are further processed by the interstellar radiation field, interstellar shocks and energetic particles. A major, dedicated, laboratory effort has been undertaken over the past years to measure the physical and chemical characteristics of these complex molecules and their ions under experimental conditions that mimic the interstellar conditions. These measurements require collision-free conditions where the molecules and ions are cold and chemically isolated. The spectroscopy of PAHs under controlled conditions represents an essential diagnostic tool to study the evolution of extraterrestrial PAHs. The Astrochemistry Laboratory program will be discussed through its multiple aspects: objectives, approach and techniques adopted, adaptability to the nature of the problem(s), results and implications for astronomy as well as for molecular spectroscopy. A review of the data generated through laboratory simulations of space environments and the role these data have played in our current understanding of the properties of interstellar PAHs will be presented. The discussion will also introduce the newest generation of laboratory experiments that are currently being developed in order to provide a closer simulation of space environments and a better support to space missions.

Salama, Farid; DeVincenzi, Donald L. (Technical Monitor)

2000-01-01

311

Hydrologic conditions and distribution of selected radiochemical and chemical constituents in water, Snake River Plain aquifer, Idaho National Engineering Laboratory, Idaho, 1992 through 1995  

SciTech Connect

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds and disposal wells at the Idaho National Engineering Laboratory (INEL) has affected water quality in the Snake River Plain aquifer. The US Geological Survey, in cooperation with the US Department of Energy, maintains a monitoring network at the INEL to determine hydrologic trends and to delineate the movement of radiochemical and chemical wastes in the aquifer. This report presents an analysis of water-level and water-quality data collected from the Snake River Plain aquifer during 1992--95.

Bartholomay, R.C.; Tucker, B.J.; Ackerman, D.J.; Liszewski, M.J.

1997-04-01

312

Semantic Similarity in Biomedical Ontologies  

PubMed Central

In recent years, ontologies have become a mainstream topic in biomedical research. When biological entities are described using a common schema, such as an ontology, they can be compared by means of their annotations. This type of comparison is called semantic similarity, since it assesses the degree of relatedness between two entities by the similarity in meaning of their annotations. The application of semantic similarity to biomedical ontologies is recent; nevertheless, several studies have been published in the last few years describing and evaluating diverse approaches. Semantic similarity has become a valuable tool for validating the results drawn from biomedical studies such as gene clustering, gene expression data analysis, prediction and validation of molecular interactions, and disease gene prioritization. We review semantic similarity measures applied to biomedical ontologies and propose their classification according to the strategies they employ: node-based versus edge-based and pairwise versus groupwise. We also present comparative assessment studies and discuss the implications of their results. We survey the existing implementations of semantic similarity measures, and we describe examples of applications to biomedical research. This will clarify how biomedical researchers can benefit from semantic similarity measures and help them choose the approach most suitable for their studies. Biomedical ontologies are evolving toward increased coverage, formality, and integration, and their use for annotation is increasingly becoming a focus of both effort by biomedical experts and application of automated annotation procedures to create corpora of higher quality and completeness than are currently available. Given that semantic similarity measures are directly dependent on these evolutions, we can expect to see them gaining more relevance and even becoming as essential as sequence similarity is today in biomedical research. PMID:19649320

Pesquita, Catia; Faria, Daniel; Falcão, André O.; Lord, Phillip; Couto, Francisco M.

2009-01-01

313

Community Detection by Neighborhood Similarity  

NASA Astrophysics Data System (ADS)

Detection of the community structure in a network is important for understanding the structure and dynamics of the network. By exploring the neighborhood of vertices, a local similarity metric is proposed, which can be quickly computed. The resulting similarity matrix retains the same support as the adjacency matrix. Based on local similarity, an agglomerative hierarchical clustering algorithm is proposed for community detection. The algorithm is implemented by an efficient max-heap data structure and runs in nearly linear time, thus is capable of dealing with large sparse networks with tens of thousands of nodes. Experiments on synthesized and real-world networks demonstrate that our method is efficient to detect community structures, and the proposed metric is the most suitable one among all the tested similarity indices.

Liu, Xu; Xie, Zheng; Yi, Dong-Yun

2012-04-01

314

The similarity join database operator  

Microsoft Academic Search

Similarity joins have been studied as key operations in multiple application domains, e.g., record linkage, data cleaning, multimedia and video applications, and phenomena detection on sensor networks. Multiple similarity join algorithms and implementation techniques have been proposed. They range from out-of-database approaches for only in-memory and external memory data to techniques that make use of standard database operators to answer

Yasin N. Silva; Walid G. Aref; Mohamed H. Ali

2010-01-01

315

[Pathogenic effect of the nematode parasite Romanomermis iyengari(Nematoda: Mermithidae) in Aedes aegypti mosquito larvae (Diptera: Culicidae) under laboratory conditions in the state of Oaxaca, Mexico].  

PubMed

Laboratory tests with waters from Aedes aegypti Linneaus (1762) breeding places were made to determine the pathogenic effect of the mermithid nematode Romanomermis iyengari Welch 1964 in mosquito larvae of this species. According to the results obtained, the administration of a dosage of 10:1 (10 preparasitics per mosquito larvae) showed levels of parasitism of 90, 93, 91, and 85% in mosquito larvae in the I, II, III, and IV stage, respectively. With the highest dosage of 20:1 (20 preparasitics per mosquito larvae) there were obtained levels of parasitism with values of 98, 97, 93 and 89% among larvae in the I, II, III, and IV stage, respectively. Generally, the values of the physical and chemical parameters such as pH, conductivity, oxygen, and chlorides calculated in these waters did not affect apparently the infective capacity of the preparasitics of R. iyengari. PMID:9842260

Santamarina Mijares, A; Pérez Pacheco, M C

1998-01-01

316

Analysis of the avoidance of nitrogen fertilizers in the water column by juvenile Iberian water frog, Pelophylax perezi (Seoane, 1885), in laboratory conditions.  

PubMed

In an experiment carried out in the laboratory in beakers, the avoidance of ammonium chloride, isolated or combined with sodium nitrite and sodium nitrate, in aquatic habitat by froglets of Pelophylax perezi was studied. The results obtained suggest that nitrogen polluted treatments were not avoided by froglets of the studied species. However, despite the non-avoidance of the aquatic environment as a consequence of the presence of nitrogen compounds, significant inter-individual variation in treatment avoidance was detected. Although these results are not conclusive, they would suggest that froglets of P. perezi might occupy habitats which contain high levels of organic compounds and that they differ in their level of avoidance to fertilizer exposure. PMID:18193144

Egea-Serrano, Andrés; Tejedo, Miguel; Torralva, Mar

2008-02-01

317

Laboratory measurements of the microwave and millimeter-wave opacity of gaseous sulfur dioxide (SO2) under simulated conditions for the Venus atmosphere  

NASA Technical Reports Server (NTRS)

Laboratory measurements have been conducted of the opacity of gaseous SO2 in a CO2 atmosphere at 12.3 cm, 1.32 cm, and 0.32 cm, with a view to the effects of this gas on the mm-wave emission of the Venus atmosphere. Close agreement is noted between the results obtained and the absorptivity predicted from a Van Vleck-Weisskopf formalism at the two shortest wavelengths, but not at the longest. These results have been incorporated into a radiative transfer model in order to infer an abundance profile for gaseous SO2 in Venus' middle atmosphere, and are also used to ascertain the effects of a SO2/CO2 gaseous mixture on the mm-wavelength spectrum of Venus.

Fahd, Antoine K.; Steffes, Paul G.

1992-01-01

318

Predation and control efficacies of Misgurnus mizolepis (Cypriniformes: Cobitidae) toward Culex pipiens molestus (Diptera: Culicidae) and fish toxicity of temephos in laboratory and septic tank conditions.  

PubMed

Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae. PMID:25118414

Chae, Seong Chun; Kwon, Young Hyun; Min, Kyung Il; Kim, Hyung Soo; Kim, Nam-Jin; Kim, Jun-Ran; Son, Bong Gi; Ahn, Young-Joon

2014-07-01

319

Thermal Performance of Biological Substance Systems in Vitro Under Static and Dynamic Conditions at the Cryogenic Test Laboratory, NASA Kennedy Space Center, USA  

NASA Technical Reports Server (NTRS)

A unique research program, including a comprehensive study of thermal performance at cryogenic vacuum insulation systems, was performed at the NASA Kennedy Space Center. The main goal was to develop a new soft vacuum system (from 1 torr to 10 torr) that provides an intermediate level of performance (k-value below 4.8 mW/m-K). Liquid nitrogen boil-off methods were used to test conventional materials, novel materials, and certain combinations. The test articles included combinations of aluminum foil, fiberglass paper, polyester fabric, silica aerogel composite blanket, fumed silica, silica aerogel powder, and syntactic foam. A new LCI system was developed at the Cryogenics Test Laboratory. This system performs exceptionally well at soft vacuum levels and nearly as good as an MLI at high vacuum levels. Apparent thermal conductivities for the LCI range from 2 mW/m-K at soft vacuum to 0.1 mW/m-K at high vacuum. Several cryostats were designed, constructed, and calibrated by the Cryogenics Test Laboratory at KSC NASA as part of this research program. The cryostat test apparatus is a liquid nitrogen boil-off calorimeter system for direct measurement of the apparent thermal conductivity at a fixed vacuum level between 5 x 10(exp -5) and 760 torr. The apparatus is also used for transient measurements of temperature profiles. The development of efficient, robust cryogenic insulation systems has been a targeted area of research for a number of years. Improved methods of characterization, testing, and evaluation of complex biological substance systems for cryosurgery and cryobiology are the focus of this paper.

Augustynowicz, S. D.; Fesmire, James E.; Steinrock, T. (Technical Monitor)

2001-01-01

320

LABORATORY POLICY WORKING ALONE  

E-print Network

& Responsibilities Template Issued By: Environmental Health &Safety Template Revision #: --Part: Laboratory Policy: ______________________________________________________________ Building and Room #'s under supervision of Dr working alone policy. 1. Policy: The following operations/experiments/conditions (specified by principal

Garousi, Vahid

321

Selection of USSR foreign similarity regions  

NASA Technical Reports Server (NTRS)

The similarity regions in the United States and Canada were selected to parallel the conditions that affect labeling and classification accuracies in the U.S.S.R. indicator regions. In addition to climate, a significant condition that affects labeling and classification accuracies in the U.S.S.R. is the proportion of barley and wheat grown in a given region (based on sown areas). The following regions in the United States and Canada were determined to be similar to the U.S.S.R. indicator regions: (1) Montana agrophysical unit (APU) 104 corresponds to the Belorussia high barley region; (2) North Dakota and Minnesota APU 20 and secondary region southern Manitoba and Saskatchewan correspond to the Ural RSFSR barley and spring wheat region; (3) Montana APU 23 corresponds to he North Caucasus barley and winter wheat region. Selection criteria included climates, crop type, crop distribution, growth cycles, field sizes, and field shapes.

Disler, J. M. (principal investigator)

1982-01-01

322

Chemical evolution of organic molecules under Mars-like UV radiation conditions simulated in the laboratory with the “Mars organic molecule irradiation and evolution” (MOMIE) setup  

NASA Astrophysics Data System (ADS)

Understanding the evolution of organic matter on Mars is a major goal to drive and discuss past, present and future in situ analyses. Here we demonstrate the ability of the MOMIE (for Mars organic molecules irradiation and evolution) laboratory device in giving both in situ qualitative and quantitative data on the evolution of organic molecules under simulated Martian surface ultraviolet light (190-400 nm), mean temperature (218±2 K) and pressure (6±1 mbar). We describe the chemical evolution of glycine, an amino acid, which is very rapidly processed when exposed to direct ultraviolet radiations, with a molecular half-life of 231±110 h on Mars consistent with existing results. Moreover we report the first tentative detection of peptide bond formation activated by UV radiation reaching the Mars surface. We show that organics as simple as glycine could experience multiple chemical pathways at Mars, both in the solid and gaseous phase. Finally, we derive the quantum efficiency for the photodestruction of glycine of 2.18±1.45×10-3 molecule photon-1 in the 200-250 nm wavelength range. This value is significantly higher than previous estimates done by methane evolved measurements. Current and future studies performed with this simulation setup could produce kinetic and chemical insights into the evolution of organics on Mars.

Poch, O.; Noblet, A.; Stalport, F.; Correia, J. J.; Grand, N.; Szopa, C.; Coll, P.

2013-09-01

323

Crowdsourced Trace Similarity with Smartphones  

E-print Network

1 Crowdsourced Trace Similarity with Smartphones Demetrios Zeinalipour-Yazti, Member, IEEE Gunopulos Member, IEEE Abstract--Smartphones are nowadays equipped with a number of sensors, such as WiFi, GPS, accelerometers, etc. This capability allows smartphone users to easily engage in crowdsourced

Zeinalipour, Demetris

324

Distance Learning for Similarity Estimation  

Microsoft Academic Search

In this paper, we present a general guideline to find a better distance measure for similarity estimation based on statistical analysis of distribution models and distance functions. A new set of distance measures are derived from the harmonic distance, the geometric distance, and their generalized variants according to the Maximum Likelihood theory. These measures can provide a more accurate feature

Jie Yu; Jaume Amores; Nicu Sebe; Petia Radeva; Qi Tian

2008-01-01

325

What Difference Reveals about Similarity  

ERIC Educational Resources Information Center

Detecting that two images are different is faster for highly dissimilar images than for highly similar images. Paradoxically, we showed that the reverse occurs when people are asked to describe "how" two images differ--that is, to state a difference between two images. Following structure-mapping theory, we propose that this disassociation arises…

Sagi, Eyal; Gentner, Dedre; Lovett, Andrew

2012-01-01

326

Active Browsing using Similarity Pyramids  

Microsoft Academic Search

In this paper, we describe a new approach to managing large image databases which we call active browsing. Active browsing integrates relevance feedback into the browsing environment, so that users can modify the database's organization to suit the desired task. Our method is based on a similarity pyramid data structure which hierarchically organizes the database so that it can be

Jau-Yuen Chen; Charles A. Bouman; John C. Dalton

327

Active Browsing using Similarity Pyramids  

Microsoft Academic Search

In this paper, we describe a new approach to managing large image databases which we call active browsing. Activebrowsing integrates relevance feedback into the browsing environment, so that users can modify the database'sorganization to suit the desired task. Our method is based on a similarity pyramid data structure which hierarchicallyorganizes the database so that it can be e#ciently browsed. At

Jau-yuen Chen; Charles A. Bouman; John C. Dalton

1999-01-01

328

Similarity methods for differential equations  

SciTech Connect

We begin with a few remarks on the scope of these lecture notes. The purpose is to give an elementary introduction to similarity methods for partial differential equations for those who have had little or nor experience with these techniques. The emphasis will be on motivation and practical calculations involving several simple examples. From time-to-time we will allude to the differential-geometric structure which underlies these concepts; for, what we are really talking about is the invariance of a partial differential equation under the action of a local, Lie group of transformations. However, a deep understanding of these general concepts is not a prerequisite for being able to apply similarity methods to a given system. The first lecture is mostly an introductory lecture on the nature of self-similar solutions. The second lecture discusses dimensional analysis and the Buckingham Pi Theorem and how dimensional arguments lead in a natural way to similarity solutions. The third and fourth lectures develop the concept of invariance under a group of transformations and, given the group, show how solutions can be constructed. In the fifth and sixth lectures we show how the invariance group can be calculated. The final lecture deals with a detailed physical example taken from the area of detonation physics.

Logan, D.

1982-01-01

329

Similarity and Induction Matthew Weber  

E-print Network

of different categories; the choice of of these regions is motivated by previous literature. The theory is clear. Similarity often lies behind inductive inference. The goal of the present essay is to sharpen subjective probability in the minds of people who misunderstand chance. (Most college students can be led

Osherson, Daniel

330

Laboratory measurements of the microwave opacity and vapor pressure of sulfuric acid vapor under simulated conditions for the middle atmosphere of Venus  

NASA Technical Reports Server (NTRS)

Microwave absorption measurements at wavelengths of 13.4 and 3.6 cm were made in gaseous H2SO4 in a CO2 atmosphere under simulated conditions for the Venus middle atmosphere. The results suggest that abundances of gaseous H2SO4 on the order of 15-30 ppm could account for the absorption observed by radio occultation measurements at these wavelengths. They also imply that such abundances would correspond to saturation vapor pressure existing at or above the 46-48-km range, which correlates with the observed cloud base.

Steffes, P. G.

1985-01-01

331

Methods for Similarity-based Virtual Screening  

PubMed Central

Developing new medical drugs is expensive. Among the first steps is a screening process, in which molecules in existing chemical libraries are tested for activity against a given target. This requires a lot of resources and manpower. Therefore it has become common to perform a virtual screening, where computers are used for predicting the activity of very large libraries of molecules, to identify the most promising leads for further laboratory experiments. Since computer simulations generally require fewer resources than physical experimentation this can lower the cost of medical and biological research significantly. In this paper we review practically fast algorithms for screening databases of molecules in order to find molecules that are sufficiently similar to a query molecule. PMID:24688702

Kristensen, Thomas G.; Nielsen, Jesper; Pedersen, Christian N. S.

2013-01-01

332

Similarities Between Tinnitus and Pain  

Microsoft Academic Search

\\u000a \\u000a \\u000a \\u000a \\u000a 1. \\u000a \\u000a Both pain and tinnitus have many different forms.\\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a Tinnitus and central neuropathic pain are phantom sensations similar to the phantom limb symptoms that occur without any physical\\u000a stimulation of sensory receptors.\\u000a \\u000a \\u000a \\u000a \\u000a 3. \\u000a \\u000a Tinnitus and neuropathic pain are typical examples of “plasticity disorders” where the symptoms are caused by plastic changes\\u000a that are not beneficial to an individual person.

Aage R. Møller

333

Drug repositioning by applying 'expression profiles' generated by integrating chemical structure similarity and gene semantic similarity.  

PubMed

Drug repositioning, also known as drug repurposing or reprofiling, is the process of finding new indications for established drugs. Because drug repositioning can reduce costs and enhance the efficiency of drug development, it is of paramount importance in medical research. Here, we present a systematic computational method to identify potential novel indications for a given drug. This method utilizes some prior knowledge such as 3D drug chemical structure information, drug-target interactions and gene semantic similarity information. Its prediction is based on another form of 'expression profile', which contains scores ranging from -1 to 1, reflecting the consensus response scores (CRSs) between each drug of 965 and 1560 proteins. The CRS integrates chemical structure similarity and gene semantic similarity information. We define the degree of similarity between two drugs as the absolute value of their correlation coefficients. Finally, we establish a drug similarity network (DSN) and obtain 33 modules of drugs with similar modes of action, determining their common indications. Using these modules, we predict new indications for 143 drugs and identify previously unknown indications for 42 drugs without ATC codes. This method overcomes the instability of gene expression profiling derived from experiments due to experimental conditions, and predicts indications for a new compound feasibly, requiring only the 3D structure of the compound. In addition, the high literature validation rate of 71.8% also suggests that our method has the potential to discover novel drug indications for existing drugs. PMID:24603772

Tan, Fujian; Yang, Ruizhi; Xu, Xiaoxue; Chen, Xiujie; Wang, Yunfeng; Ma, Hongzhe; Liu, Xiangqiong; Wu, Xin; Chen, Yuelong; Liu, Lei; Jia, Xiaodong

2014-05-01

334

Laboratory 10 Control Systems Laboratory ECE3557 Laboratory 10  

E-print Network

Laboratory 10 Control Systems Laboratory ECE3557 Laboratory 10 State Feedback Controller.87 Ã? 10-7 kg-m2 , and Jl = 3 Ã? 10-5 kg-m2 . Page 1 of 7 #12;Laboratory 10 Control Systems Laboratory ECE;Laboratory 10 Control Systems Laboratory ECE3557 10.3 Laboratory Preparation 1. Write a MATLAB script

335

Similarity considerations for acoustic agglomeration  

NASA Astrophysics Data System (ADS)

Acoustic agglomerators work, not only in reducing the total number concentration but also to effectively shift the size distribution to a larger size range depending on the frequency and intensity applied to the particular particle size distribution. The acoustic agglomerator is like any other conventional particulate abatement device from the viewpoint, that the design, materials and construction are dictated solely for that particular application and given system conditions. In addition, the acoustic agglomerator has to be tuned to that specific application for best results. In spite of the low efficiencies of sound generators, the total energy consumption is small, rapidly increasing at the higher sound intensity levels where turbulence dominates, wherein the amount of useful energy for agglomeration is smaller relative to the input acoustic energy, although it is counter benefitted by the increase in the rate of agglomeration and removal. Thus it is the availability of space and costs which inherently decides the rates of agglomeration and removal which indirectly determines the intensity levels to be used.

Patel, S.; Shaw, D. T.

1980-06-01

336

General sound classification and similarity in MICHAEL CASEY  

E-print Network

General sound classification and similarity in MPEG-7 MICHAEL CASEY MERL Cambridge Research Laboratory, Cambridge, USA E-mail: casey@merl.com We introduce a system for generalised sound classification of environmental sounds, musical instruments, music genre and human speakers. In addition to classification

Casey, Michael

337

LANGUAGE LABORATORIES.  

ERIC Educational Resources Information Center

THE USE OF THE LANGUAGE LABORATORY HAS GIVEN MANY THOUSANDS OF INDIVIDUALS GOOD LISTENING AND SPEAKING PRACTICE AND HAS BECOME AN EFFECTIVE LEARNING TOOL. THE BASIC PIECE OF EQUIPMENT OF THE LANGUAGE LABORATORY IS THE TAPE RECORDER-AND-PLAYBACK, DESIGNED TO BE USED WITH AUDIOPASSIVE STUDY, AUDIOACTIVE STUDY, AUDIOACTIVE-COMPARATIVE STUDY, AND…

BRUBAKER, CHARLES WILLIAM

338

Asymptotic similarity in turbulent boundary layers  

NASA Astrophysics Data System (ADS)

The turbulent boundary layer is one of the most fundamental and important applications of fluid mechanics. Despite great practical interest and its direct impact on frictional drag among its many important consequences, no theory absent of significant inference or assumption exists. Numerical simulations and empirical guidance are used to produce models and adequate predictions, but even minor improvements in modeling parameters or physical understanding could translate into significant improvements in the efficiency of aerodynamic and hydrodynamic vehicles. Classically, turbulent boundary layers and fully-developed turbulent channels and pipes are considered members of the same "family," with similar "inner" versus "outer" descriptions. However, recent advances in experiments, simulations, and data processing have questioned this, and, as a result, their fundamental physics. To address a full range of pressure gradient boundary layers, a new approach to the governing equations and physical description of wall-bounded flows is formulated, using a two variable similarity approach and many of the tools of the classical method with slight but significant variations. A new set of similarity requirements for the characteristic scales of the problem is found, and when these requirements are applied to the classical "inner" and "outer" scales, a "similarity map" is developed providing a clear prediction of what flow conditions should result in self-similar forms. An empirical model with a small number of parameters and a form reminiscent of Coles' "wall plus wake" is developed for the streamwise Reynolds stress, and shown to fit experimental and numerical data from a number of turbulent boundary layers as well as other wall-bounded flows. It appears from this model and its scaling using the free-stream velocity that the true asymptotic form of u'2 may not become self-evident until Retheta ? 275,000 or delta+ ? 105, if not higher. A perturbation expansion made possible by the novel inclusion of the scaled streamwise coordinate is used to make an excellent prediction of the shear Reynolds stress in zero pressure gradient boundary layers and channel flows, requiring only a streamwise mean velocity profile and the new similarity map. Extension to other flows is promising, though more information about the normal Reynolds stresses is needed. This expansion is further used to infer a three layer structure in the turbulent boundary layer, and modified two layer structure in fully-developed flows, by using the classical inner and logarithmic profiles to determine which portions of the boundary layer are dominated by viscosity, inertia, or turbulence. A new inner function for U+ is developed, based on the three layer description, providing a much more simplified representative form of the streamwise mean velocity nearest the wall.

Duncan, Richard D.

339

Magnitude -7 level earthquakes: A new lower limit of self-similarity in seismic scaling relationships  

NASA Astrophysics Data System (ADS)

occurring in a rock sample that are called acoustic emission (AE) events show some similar features to earthquakes. However, it remains to be shown whether or not AE equate to ultramicroearthquakes. In this study, we show the existence of magnitude -7 level earthquakes based on seismological analyses of AE source parameters. Advances in multichannel, broadband, high-speed continuous recording of AE under seismogenic pressure conditions has facilitated increasingly robust measurement. Source parameters of AE show that AE events satisfy the same scaling relationship as natural earthquakes in which seismic moment is inversely proportional to the cube of corner frequency. This result suggests that both millimeter scale fractures and natural earthquakes of kilometer scale ruptures are highly similar as physical processes. Hence, AE events can be interpreted as ultramicroearthquakes having a magnitude of about -7. These results demonstrate that laboratory observation is an effective approach in studying natural earthquake generation process.

Yoshimitsu, Nana; Kawakata, Hironori; Takahashi, Naoki

2014-07-01

340

Paleomagnetics Laboratory  

NSDL National Science Digital Library

At this website, the California Institute of Technology's Paleomagnetics Laboratory promotes its research of weakly magnetic geologic and biological materials. Users can learn about the facilities such as the biomagnetics lab and the automatic sampler. The website features the laboratory's recent research on many topics including extraterrestrial magnetism, magnetofossils, and historical geomagnetic field behavior. Visitors can find out more about the many laboratory members' research activities through links to their home pages. Researchers can download a selection of the group's publications. Everyone can enjoy the amazing images from recent geologic field trips across the globe.

341

Hepatic venous outflow obstruction: Three similar syndromes  

PubMed Central

Our goal is to provide a detailed review of veno-occlusive disease (VOD), Budd-Chiari syndrome (BCS), and congestive hepatopathy (CH), all of which results in hepatic venous outflow obstruction. This is the first article in which all three syndromes have been reviewed, enabling the reader to compare the characteristics of these disorders. The histological findings in VOD, BCS, and CH are almost identical: sinusoidal congestion and cell necrosis mostly in perivenular areas of hepatic acini which eventually leads to bridging fibrosis between adjacent central veins. Tender hepatomegaly with jaundice and ascites is common to all three conditions. However, the clinical presentation depends mostly on the extent and rapidity of the outflow obstruction. Although the etiology and treatment are completely different in VOD, BCS, and CH; the similarities in clinical manifestations and liver histology may suggest a common mechanism of hepatic injury and adaptation in response to increased sinusoidal pressure. PMID:17461490

Bayraktar, Ulas Darda; Seren, Soley; Bayraktar, Yusuf

2007-01-01

342

Drug-induced acne and rose pearl: similarities.  

PubMed

Drug-induced acne is a common skin condition whose classic symptoms can be similar to a rose pearl, as in the case of a male patient presenting with this condition after excessive use of a cream containing corticosteroids. PMID:24474128

Pontello, Rubens; Kondo, Rogerio Nabor

2013-01-01

343

Environmental Conditions Environmental Conditions  

E-print Network

, developed complex life histories through time that responded to the subbasin's considerable variation in this habitat. Loss of grassland habitat greatly reduced such populations. Today subbasin habitat conditions/optimal) conditions in the year 2050, and examines what future conditions might be expected if no additional future

344

Laboratory Studies of Interstellar PAH Analogs  

NASA Technical Reports Server (NTRS)

Polycyclic aromatic hydrocarbons (PAHs) are now considered to be an important and ubiquitous component of the organic material in space. PAHs are found in a large variety of extraterrestrial materials such as interplanetary dust particles (IDPs) and meteoritic materials. PAHs are also good candidates to account for the infrared emission bands (UIRs) and the diffuse interstellar optical absorption bands (DIBs) detected in various regions of the interstellar medium. The recent observations made with the Infrared Space Observatory (ISO) have confirmed the ubiquitous nature of the UIR bands and their carriers. PAHs are though to form through chemical reactions in the outflow from carbon-rich stars in a process similar to soot formation. Once injected in the interstellar medium, PAHs are further processed by the interstellar radiation field, interstellar shocks and energetic particles. A major, dedicated, laboratory effort has been undertaken over the past years to measure the physical and chemical characteristics of these complex molecules and their ions under experimental conditions that mimic the interstellar conditions. These measurements require collision-free conditions where the molecules and ions are cold and chemically isolated. The spectroscopy of PAHs under controlled conditions represents an essential diagnostic tool to study the evolution of extraterrestrial PAHs. The Astrochemistry Laboratory program will be discussed through its multiple aspects: objectives, approach and techniques adopted, adaptability to the nature of the problem(s), results and implications for astronomy as well as for molecular spectroscopy. A review of the data generated through laboratory simulations of space environments and the role these data have played in our current understanding of the properties of interstellar PAHs will be presented. The discussion will also introduce the newest generation of laboratory experiments that are currently being developed in order to provide a closer simulation of space environments and a better support to space missions.

Salama, Farid; DeVincenzi, Donald (Technical Monitor)

2000-01-01

345

Similarity constraints in testing of cooled engine parts  

NASA Technical Reports Server (NTRS)

A study is made of the effect of testing cooled parts of current and advanced gas turbine engines at the reduced temperature and pressure conditions which maintain similarity with the engine environment. Some of the problems facing the experimentalist in evaluating heat transfer and aerodynamic performance when hardware is tested at conditions other than the actual engine environment are considered. Low temperature and pressure test environments can simulate the performance of actual size prototype engine hardware within the tolerance of experimental accuracy if appropriate similarity conditions are satisfied. Failure to adhere to these similarity constraints because of test facility limitations or other reasons, can result in a number of serious errors in projecting the performance of test hardware to engine conditions.

Colladay, R. S.; Stepka, F. S.

1974-01-01

346

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2010 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the requirements...

2010-10-01

347

42 CFR 493.1215 - Condition: Hematology.  

Code of Federal Regulations, 2010 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Hematology. If the laboratory provides services in the specialty of Hematology, the laboratory must meet the requirements...

2010-10-01

348

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2012 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the requirements...

2012-10-01

349

42 CFR 493.1215 - Condition: Hematology.  

Code of Federal Regulations, 2012 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Hematology. If the laboratory provides services in the specialty of Hematology, the laboratory must meet the requirements...

2012-10-01

350

42 CFR 493.1215 - Condition: Hematology.  

Code of Federal Regulations, 2013 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Hematology. If the laboratory provides services in the specialty of Hematology, the laboratory must meet the requirements...

2013-10-01

351

42 CFR 493.1215 - Condition: Hematology.  

Code of Federal Regulations, 2011 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Hematology. If the laboratory provides services in the specialty of Hematology, the laboratory must meet the requirements...

2011-10-01

352

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2011 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the requirements...

2011-10-01

353

42 CFR 493.1203 - Condition: Mycology.  

Code of Federal Regulations, 2013 CFR

...STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Quality System for Nonwaived Testing § 493...Condition: Mycology. If the laboratory provides services in the subspecialty of Mycology, the laboratory must meet the requirements...

2013-10-01

354

Beyond Literal Similarity. Technical Report No. 105.  

ERIC Educational Resources Information Center

Hitherto, theories of similarity have restricted themselves to judgments of what might be called literal similarity. A central thesis of this paper is that a complete account of similarity needs also to be sensitive to nonliteralness, or metaphoricity, an aspect of similarity statements that is most evident in similes, but that actually underlies…

Ortony, Andrew

355

Emulating Human Perception of Motion Similarity  

Microsoft Academic Search

Evaluating the similarity of motions is useful for motion retrieval, motion blending, and performance analysis of dancers and athletes. Euclidean distance between corresponding joints has been widely adopted in measuring similarity of postures and hence motions. However, such a measure does not necessarily conform to the human perception of motion similarity. In this paper, we propose a new similarity measure

Jeff K. T. Tang; Howard Leung; Taku Komura; Hubert P. H. Shum

2008-01-01

356

Emergency Procedure Training for Reactor Operators at the High Flux Beam Reactor for Brookhaven National Laboratory.  

ERIC Educational Resources Information Center

A project was conducted to analyze, design, develop, implement, and evaluate an instructional unit intended to improve the diagnostic skills of operating personnel in responding to abnormal and emergency conditions at the High Flux Beam Reactor at Brookhaven National Laboratory. Research was conducted on the occurrence of emergencies at similar

Reyer, Ronald

357

Laboratory 11 Control Systems Laboratory ECE3557 Laboratory 11  

E-print Network

Laboratory 11 Control Systems Laboratory ECE3557 Laboratory 11 State Feedback Controller of the combined system (i.e., servomotor and flexible joint) introduced in the Laboratory 8 (refer to [1 of the flexible joint: Page 1 of 7 #12;Laboratory 11 Control Systems Laboratory ECE3557 · : motor shaft position

358

Lawrence Livermore National Laboratory hot spot mobile laboratory  

Microsoft Academic Search

Gross alpha\\/beta\\/tritium liquid The Hot Spot Mobile Laboratory is an asset used to analyze samples (some high hazard) from the field. Field laboratories allow the quick turnaround of samples needed to establish weapon condition and hazard assessment for the protection of responders and the public. The Hot Spot Lab is configured to fly anywhere in the world and is staffed

Buddemeier

1999-01-01

359

Similarities in acute temperature preferences of freshwater fishes  

SciTech Connect

A statistical analysis of new and published laboratory data revealed strong geographic similarities in acute (up to 4-h) temperature preferences for several freshwater fishes. Regression models developed from our laboratory studies predicted acute temperature preferences of species from other geographic areas. Species within a family (three cyprinids, two ictalurids, and six centrarchids were tested) have similar acute preferenda, except that white crappie (Pomoxis annularis) differs from other centrarchids. For the species analyzed, acclimation temperature is the only significant variable affecting acute preferenda and accounted for up to 82% of the total variation. These emerging generalities should minimize the need for further site-specific studies of acute temperature preference for individual species and thus should result in substantial savings in money and time.

Mathur, D. (Muddy Run Ecological Lab., Drumore, PA); Schutsky, R.M.; Purdy, E.J. Jr.; Silver, C.

1981-01-01

360

Appalachian Laboratory  

NSDL National Science Digital Library

Located in Frostburg, Maryland, AL conducts research in aquatic ecology, landscape and watershed ecology, conservation biology and restoration ecology, behavioral and evolutionary ecology, and study both freshwater and terrestrial ecosystems of Maryland and other locations in the United States and the world. Site contains information regarding the facilities, faculty, on going research, education opportunities, and seminars. Also features information on the other UMCES laboratories.

361

BROOKHAVEN LABORATORY  

E-print Network

, and decision-making processes. We will endeavor to support parents in their critical role. 2. Children develop that stimulates academic/cognitive growth, language, social-emotional development and physical developmentBROOKHAVEN NATIONAL LABORATORY Child Development Center Parent Handbook Revised 2009

Ohta, Shigemi

362

Appalachian Laboratory  

NSDL National Science Digital Library

Located in Frostburg, Maryland, AL conducts research in aquatic ecology, landscape and watershed ecology, conservation biology and restoration ecology, behavioral and evolutionary ecology, and study both freshwater and terrestrial ecosystems of Maryland and other locations in the United States and the world. Site contains information regarding the facilities, faculty, on going research, education opportunities, and seminars. Also features information on the other UMCES laboratories.

2011-06-14

363

Acute encephalopathy in children in Nagpur: similarity to Reye's syndrome  

Microsoft Academic Search

The clinical, laboratory and histopathological features of the Nagpur encephalopathy syndrome and those of Reye's syndrome\\u000a have been reviewed and found to be strikingly similar. Microvesicular fatty infiltration of hepatic parenchymal cells characteristic\\u000a of Reye's syndrome was seen in two of three liver specimens collected at autopsy from cases of the Nagpur encephalopathy syndrome.\\u000a Therefore we suggest that this illness

T. Jacob John; Anand Date; N. K. Patoria

1983-01-01

364

42 CFR 493.1221 - Condition: Cytology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Cytology. 493.1221 Section 493.1221...Testing § 493.1221 Condition: Cytology. If the laboratory provides services in the subspecialty of Cytology, the laboratory must meet the...

2013-10-01

365

42 CFR 493.1221 - Condition: Cytology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Cytology. 493.1221 Section 493.1221...Testing § 493.1221 Condition: Cytology. If the laboratory provides services in the subspecialty of Cytology, the laboratory must meet the...

2010-10-01

366

42 CFR 493.1221 - Condition: Cytology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Cytology. 493.1221 Section 493.1221...Testing § 493.1221 Condition: Cytology. If the laboratory provides services in the subspecialty of Cytology, the laboratory must meet the...

2011-10-01

367

42 CFR 493.1221 - Condition: Cytology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Cytology. 493.1221 Section 493.1221...Testing § 493.1221 Condition: Cytology. If the laboratory provides services in the subspecialty of Cytology, the laboratory must meet the...

2012-10-01

368

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Virology. 493.1205 Section 493.1205...Testing § 493.1205 Condition: Virology. If the laboratory provides services in the subspecialty of Virology, the laboratory must meet the...

2011-10-01

369

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Virology. 493.1205 Section 493.1205...Testing § 493.1205 Condition: Virology. If the laboratory provides services in the subspecialty of Virology, the laboratory must meet the...

2010-10-01

370

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Virology. 493.1205 Section 493.1205...Testing § 493.1205 Condition: Virology. If the laboratory provides services in the subspecialty of Virology, the laboratory must meet the...

2013-10-01

371

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Virology. 493.1205 Section 493.1205...Testing § 493.1205 Condition: Virology. If the laboratory provides services in the subspecialty of Virology, the laboratory must meet the...

2012-10-01

372

42 CFR 493.1201 - Condition: Bacteriology.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Condition: Bacteriology. 493.1201 Section 493...Testing § 493.1201 Condition: Bacteriology. If the laboratory provides services in the subspecialty of Bacteriology, the laboratory must meet the...

2010-10-01

373

42 CFR 493.1201 - Condition: Bacteriology.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Condition: Bacteriology. 493.1201 Section 493...Testing § 493.1201 Condition: Bacteriology. If the laboratory provides services in the subspecialty of Bacteriology, the laboratory must meet the...

2011-10-01

374

42 CFR 493.1201 - Condition: Bacteriology.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Condition: Bacteriology. 493.1201 Section 493...Testing § 493.1201 Condition: Bacteriology. If the laboratory provides services in the subspecialty of Bacteriology, the laboratory must meet the...

2012-10-01

375

42 CFR 493.1201 - Condition: Bacteriology.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Condition: Bacteriology. 493.1201 Section 493...Testing § 493.1201 Condition: Bacteriology. If the laboratory provides services in the subspecialty of Bacteriology, the laboratory must meet the...

2013-10-01

376

Self-Similarity in General Relativity \\endtitle  

E-print Network

The different kinds of self-similarity in general relativity are discussed, with special emphasis on similarity of the ``first'' kind, corresponding to spacetimes admitting a homothetic vector. We then survey the various classes of self-similar solutions to Einstein's field equations and the different mathematical approaches used in studying them. We focus mainly on spatially homogenous and spherically symmetric self-similar solutions, emphasizing their possible roles as asymptotic states for more general models. Perfect fluid spherically symmetric similarity solutions have recently been completely classified, and we discuss various astrophysical and cosmological applications of such solutions. Finally we consider more general types of self-similar models.

B. J. Carr; A. A. Coley

1998-06-09

377

Lunar laboratory  

SciTech Connect

An international research laboratory can be established on the Moon in the early years of the 21st Century. It can be built using the transportation system now envisioned by NASA, which includes a space station for Earth orbital logistics and orbital transfer vehicles for Earth-Moon transportation. A scientific laboratory on the Moon would permit extended surface and subsurface geological exploration; long-duration experiments defining the lunar environment and its modification by surface activity; new classes of observations in astronomy; space plasma and fundamental physics experiments; and lunar resource development. The discovery of a lunar source for propellants may reduce the cost of constructing large permanent facilities in space and enhance other space programs such as Mars exploration. 29 refs.

Keaton, P.W.; Duke, M.B.

1986-01-01

378

Laboratory accreditation  

SciTech Connect

Accreditation can offer many benefits to a testing or calibration laboratory, including increased marketability of services, reduced number of outside assessments, and improved quality of services. Compared to ISO 9000 registration, the accreditation process includes a review of the entire quality system, but in addition a review of testing or calibration procedures by a technical expert and participation in proficiency testing in the areas of accreditation. Within the DOE, several facilities have recently become accredited in the area of calibration, including Sandia National Laboratories, Oak Ridge, AlliedSignal FM and T; Lockheed Martin Idaho Technologies Co., and Pacific Northwest National Lab. At the national level, a new non-profit organization was recently formed called the National Cooperation for Laboratory Accreditation (NACLA). The goal of NACLA is to develop procedures, following national and international requirements, for the recognition of competent accreditation bodies in the US. NACLA is a voluntary partnership between the public and private sectors with the goal of a test or calibration performed once and accepted world wide. The NACLA accreditation body recognition process is based on the requirements of ISO Guide 25 and Guide 58. A membership drive will begin some time this fall to solicit organizational members and an election of a permanent NACLA Board of Directors will follow later this year or early 1999.

Pettit, R.B.

1998-08-01

379

Cross-reactivity of steroid hormone immunoassays: clinical significance and two-dimensional molecular similarity prediction  

PubMed Central

Background Immunoassays are widely used in clinical laboratories for measurement of plasma/serum concentrations of steroid hormones such as cortisol and testosterone. Immunoassays can be performed on a variety of standard clinical chemistry analyzers, thus allowing even small clinical laboratories to do analysis on-site. One limitation of steroid hormone immunoassays is interference caused by compounds with structural similarity to the target steroid of the assay. Interfering molecules include structurally related endogenous compounds and their metabolites as well as drugs such as anabolic steroids and synthetic glucocorticoids. Methods Cross-reactivity of a structurally diverse set of compounds were determined for the Roche Diagnostics Elecsys assays for cortisol, dehydroepiandrosterone (DHEA) sulfate, estradiol, progesterone, and testosterone. These data were compared and contrasted to package insert data and published cross-reactivity studies for other marketed steroid hormone immunoassays. Cross-reactivity was computationally predicted using the technique of two-dimensional molecular similarity. Results The Roche Elecsys Cortisol and Testosterone II assays showed a wider range of cross-reactivity than the DHEA sulfate, Estradiol II, and Progesterone II assays. 6-Methylprednisolone and prednisolone showed high cross-reactivity for the cortisol assay, with high likelihood of clinically significant effect for patients administered these drugs. In addition, 21-deoxycortisol likely produces clinically relevant cross-reactivity for cortisol in patients with 21-hydroxylase deficiency, while 11-deoxycortisol may produce clinically relevant cross-reactivity in 11?-hydroxylase deficiency or following metyrapone challenge. Several anabolic steroids may produce clinically significant false positives on the testosterone assay, although interpretation is limited by sparse pharmacokinetic data for some of these drugs. Norethindrone therapy may impact immunoassay measurement of testosterone in women. Using two-dimensional similarity calculations, all compounds with high cross-reactivity also showed a high degree of similarity to the target molecule of the immunoassay. Conclusions Compounds producing cross-reactivity in steroid hormone immunoassays generally have a high degree of structural similarity to the target hormone. Clinically significant interactions can occur with structurally similar drugs (e.g., prednisolone and cortisol immunoassays; methyltestosterone and testosterone immunoassays) or with endogenous compounds such as 21-deoxycortisol that can accumulate to very high concentrations in certain disease conditions. Simple similarity calculations can help triage compounds for future testing of assay cross-reactivity. PMID:25071417

2014-01-01

380

7 CFR 51.1997 - Similar type.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 2010-01-01 false Similar type. 51.1997 Section 51.1997 Agriculture Regulations of the Department of Agriculture...Grades of Filberts in the Shell 1 Definitions § 51.1997 Similar type. Similar type means that the...

2010-01-01

381

Thematic Relations Affect Similarity via Commonalities  

ERIC Educational Resources Information Center

Thematic relations are an important source of perceived similarity. For instance, the "rowing" theme of boats and oars increases their perceived similarity. The mechanism of this effect, however, has not been specified previously. The authors investigated whether thematic relations affect similarity by increasing commonalities or by decreasing…

Golonka, Sabrina; Estes, Zachary

2009-01-01

382

Distances and Similarities of Saturated Computational Verbs  

Microsoft Academic Search

The distance and similarity between two computa- tional verbs are very important to many applications involving the comparison of computational verbs. For example, in computa- tional verb inferences, the similarities among computational verbs decide the firing levels of computational verb rules. In this paper, the comprehensive definitions of verb distance and similarity were given based on the saturated evolving functions

Tao Yang

2006-01-01

383

Music Similarity Measures: What's the use?  

Microsoft Academic Search

Electronic Music Distribution (EMD) is in demand of robust, automatically extracted music descriptors. We introduce a timbral similarity measures for comparing music titles. This measure is based on a Gaussian model of cepstrum coefficients. We describe the timbre extractor and the corresponding timbral similarity relation. We describe experiments in assessing the quality of the similarity relation, and show that the

Jean-julien Aucouturier; François Pachet

2002-01-01

384

Impact of Similarity Measures on Webpage Clustering  

Microsoft Academic Search

Clustering of web documents enables (semi-)automatedcategorization, and facilitates certain types of search.Any clustering method has to embed the documentsin a suitable similarity space. While several clusteringmethods and the associated similarity measures havebeen proposed in the past, there is no systematic comparativestudy of the impact of similarity metrics oncluster quality, possibly because the popular cost criteriado not readily translate across qualitatively

Er Strehl; Joydeep Ghosh; Raymond Mooney

2000-01-01

385

Laboratory 12 Control Systems Laboratory ECE3557 Laboratory 12  

E-print Network

Laboratory 12 Control Systems Laboratory ECE3557 Laboratory 12 State Feedback Controller of the combined system (i.e., servomotor and flexible link) introduced in the Laboratory 9 (refer to [1 Systems Laboratory ECE3557 · : motor shaft position, measured using channel 1 encoder "ENC1" · : angular

386

[Laboratory animal; allergy; asthma].  

PubMed

Laboratory animal allergy (LAA) may develop when susceptible persons are exposed to allergens produced by laboratory animals. LAA is associated with exposure to urine, fur, and salivae of rats, guinea pigs, dogs and rabbits. Approximately 30% of persons who are exposed to laboratory animals may develop LAA and some will also develop asthma. LAA is most likely to occur in persons with previously known allergies, especially to domestic pets. The majority of LAA sufferers experience symptoms within six months their first exposure to laboratory animals; almost all develop symptoms within three years. The most common symptoms are watery eyes and an itchy, runny nose, although skin symptoms and lower respiratory tract symptoms may also occur. Feeding and handling laboratory animals or cleaning their cages generates ten times the amount of allergens compared with undisturbed conditions. Prevention of animal allergy depends on control of allergenic material in the work environment and on organizational and individual protection measures. Pre-placement evaluation and periodic medical surveillance of workers are important pieces of the overall occupational health programme. The emphasis of these medical evaluations should be on counselling and early disease detection. PMID:22022762

Corradi, M; Romano, C; Mutti, A

2011-01-01

387

Video concept classification using video similarity scores  

US Patent & Trademark Office Database

A method for determining a semantic concept classification for a digital video clip, comprising: receiving an audio-visual dictionary including a plurality of audio-visual grouplets, the audio-visual grouplets including visual background and foreground codewords, audio background and foreground codewords, wherein the codewords in a particular audio-visual grouplet were determined to be correlated with each other; determining reference video codeword similarity scores for a set of reference video clips; determining codeword similarity scores for the digital video clip; determining a reference video similarity score for each reference video clip representing a similarity between the digital video clip and the reference video clip responsive to the audio-visual grouplets, the codeword similarity scores and the reference video codeword similarity scores; and determining one or more semantic concept classifications using trained semantic classifiers responsive to the determined reference video similarity scores.

2014-04-15

388

Laboratory simulation of turbulent convection over an urban heat island  

SciTech Connect

A systematic experimental study of the heat-island-induced circulation under turbulent conditions was conducted in the laboratory for an idealized, circular heat island in an initially thermally stratified fluid (water) in a convection tank with no ambient flow. The primary objectives of the study were to obtain a better understanding of the mean and turbulent flow generated by the heat island and to identify the appropriate similarity parameters and scales for simulating such a flow. Three non-dimensional similarity parameters were derived from the governing equations of motion. They are the convection Reynolds number (Re), the Froude number (Fr), and the Prandtl number (Pr). The data indicate that at sufficiently large Re, turbulent convection in the main flow becomes independent of Re which is the basis of the laboratory simulation. These measurements are also compared with field data from several cities and they agree with each other satisfactorily.

Lu, J.; Arya, S.P.S.; Snyder, W.H.; Lawson, R.E.

1992-01-01

389

On the Existence of a Self-Similar Coarse Graining of a Self-Similar Space  

E-print Network

A topological space homeomorphic to a self-similar space is demonstrated to be self-similar. There exists a self-similar space $S$ whose coarse graining is homeomorphic to $S$. The coarse graining of $S$ is, therefore, self-similar again. In the same way, the coarse graining of the self-similar coarse graining of $S$ is, furthermore, self-similar. These situations succeed endlessly. Such a self-similar $S$ is generated actually from an intense quadratic dynamics.

Akihiko Kitada; Tomoyuki Yamamoto; Tsuyoshi Yoshioka; Shousuke Ohmori

2011-07-21

390

Archimedes Laboratory  

NSDL National Science Digital Library

Proving that geometry can be more fun than a barrel of monkeys, Archimedes Laboratory is "an 'intuitive' puzzle site with fewer formulas and more visuals, which may encourage students learning this science or just constitute a platform for reflection." Probably the most strictly educational section of the site is Math to Discover, which contains discussions of the history of numbers and mathematical patterns, to name a few. Also of interest are the Puzzles to Make and Puzzles to Solve sections. Visitors can follow online instructions to create geometrical curiosities or browse a small selection of impossible object images.

391

Teaching In The Laboratory A laboratory exercise to illustrate increased salivary cortisol in response to  

E-print Network

Teaching In The Laboratory A laboratory exercise to illustrate increased salivary cortisol. A laboratory exercise to illustrate increased salivary cortisol in response to three stressful conditions using to illustrate the response of salivary cortisol concentrations to three stressful conditions. Twelve under

Vleck, Carol

392

A new airway device for small laboratory animals.  

PubMed

There is a need for a device for improved management of the airway of small laboratory animals during general anaesthesia. This report introduces such a device, referred to here as the airway device (AD). The AD has some similarity to the laryngeal mask airway (LMA) developed for human patients, but the mask portion of the device is specifically designed for small laboratory animals. In addition, the device has an oesophageal extension and unlike the LMA does not have a cuff associated with the mask. This report also shares experience of tests of one prototype AD with six New Zealand white rabbits. The AD was used for administering isoflurane and its effectiveness was evaluated during conditions of spontaneous and controlled intermittent positive pressure ventilation. The results provide encouragement for further development of the AD for airway management of small laboratory animals. PMID:15703132

Imai, A; Eisele, P H; Steffey, E P

2005-01-01

393

Surface-based protein binding pocket similarity.  

PubMed

Protein similarity comparisons may be made on a local or global basis and may consider sequence information or differing levels of structural information. We present a local three-dimensional method that compares protein binding site surfaces in full atomic detail. The approach is based on the morphological similarity method which has been widely applied for global comparison of small molecules. We apply the method to all-by-all comparisons two sets of human protein kinases, a very diverse set of ATP-bound proteins from multiple species, and three heterogeneous benchmark protein binding site data sets. Cases of disagreement between sequence-based similarity and binding site similarity yield informative examples. Where sequence similarity is very low, high pocket similarity can reliably identify important binding motifs. Where sequence similarity is very high, significant differences in pocket similarity are related to ligand binding specificity and similarity. Local protein binding pocket similarity provides qualitatively complementary information to other approaches, and it can yield quantitative information in support of functional annotation. PMID:21769944

Spitzer, Russell; Cleves, Ann E; Jain, Ajay N

2011-09-01

394

42 CFR 493.1445 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2013 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2013-10-01

395

42 CFR 493.1407 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2013 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2013-10-01

396

42 CFR 493.1445 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2011 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2011-10-01

397

42 CFR 493.1407 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2011 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2011-10-01

398

42 CFR 493.1445 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2012 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2012-10-01

399

42 CFR 493.1407 - Standard; Laboratory director responsibilities.  

Code of Federal Regulations, 2012 CFR

...laboratory provide quality laboratory services for all aspects...postanalytic phases of testing; (2) Ensure that the physical plant and environmental conditions of the laboratory are appropriate for the testing performed and...

2012-10-01

400

Virtual Laboratories  

E-print Network

At the frontier of most areas in science, computer simulations play a central role. The traditional division of natural science into experimental and theoretical investigations is now completely outdated. Instead, theory, simulation, and experimentation form three equally essential aspects, each with its own unique flavor and challenges. Yet, education in computational science is still lagging far behind, and the number of text books in this area is minuscule compared to the many text books on theoretical and experimental science. As a result, many researchers still carry out simulations in a haphazard way, without properly setting up the computational equivalent of a well equipped laboratory. The art of creating such a virtual laboratory, while providing proper extensibility and documentation, is still in its infancy. A new approach is described here, Open Knowledge, as an extension of the notion of Open Source software. Besides open source code, manuals, and primers, an open knowledge project provides simulated dialogues between code developers, thus sharing not only the code, but also the motivations behind the code.

Piet Hut

2006-10-07

401

Using landscapelevel assessments of similarity to improve stateandtransition model development  

E-print Network

of rangeland health provide land managers and technical specialist with a good communication tool a protocol that measures the similarity of ecological site units to undesired conditions and identifies. Benchmarks are standards against which the values of indicators can be compared and judged #12;http

402

Structural similarity-based object tracking in multimodality surveillance videos  

Microsoft Academic Search

This paper addresses the problem of object track- ing in video sequences for surveillance applications by using a recently proposed structural similarity-based image dis- tance measure. Multimodality surveillance videos pose spe- cific challenges to tracking algorithms, due to, for example, low or variable light conditions and the presence of spurious or camouflaged objects. These factors often cause undesired luminance and

Artur Loza; Lyudmila Mihaylova; David R. Bull; Cedric Nishan Canagarajah

2009-01-01

403

Measures of similarity in models of categorization  

Microsoft Academic Search

This paper concerns the use of similarities based on geometric distance in models of categorization. Two problematic implications\\u000a of such similarities are outlined. First, in a comparison between two stimuli, geometric distance implies that matching features\\u000a are not taken into account. Second, missing features are assumed not to exist. Only nonmatching features enter into calculations\\u000a of similarity. A new model

Tom Verguts; Eef Ameel; Gert Storms

2004-01-01

404

Measuring Similarity Between Dynamic Ensembles of Biomolecules  

PubMed Central

Methods for comparing ensembles of biomolecules assess the population overlap between distributions but fail to fully quantify structural similarity. We present a simple and general approach for quantifying population overlap and structural similarity between ensembles. This approach captures improvements in the quality of ensembles determined using increasing input experimental data that go undetected using conventional methods and reveals unexpected similarities between RNA ensembles determined using NMR and molecular dynamics simulations. PMID:24705474

Yang, Shan; Salmon, Loic; Al-Hashimi, Hashim M.

2014-01-01

405

Reasoning about molecular similarity and properties.  

PubMed

Ascertaining the similarity amongst molecules is a fundamental problem in biology and drug discovery. Since similar molecules tend to have similar biological properties, the notion of molecular similarity plays an important role in exploration of molecular structural space, query-retrieval in molecular databases, and in structure-activity modeling. This problem is related to the issue of molecular representation. Currently, approaches with high descriptive power like 3D surface-based representations are available. However, most techniques tend to focus on 2D graph-based molecular similarity due to the complexity that accompanies reasoning with more elaborate representations. This paper addresses the problem of determining similarity when molecules are described using complex surface-based representations. It proposes an intrinsic, spherical representation that systematically maps points on a molecular surface to points on a standard coordinate system (a sphere). Molecular geometry, molecular fields, and effects due to field super-positioning can then be captured as distributions on the surface of the sphere. Molecular similarity is obtained by computing the similarity of the corresponding property distributions using a novel formulation of histogram-intersection. This method is robust to noise, obviates molecular pose-optimization, can incorporate conformational variations, and facilitates highly efficient determination of similarity. Retrieval performance, applications in structure-activity modeling of complex biological properties, and comparisons with existing research and commercial methods demonstrate the validity and effectiveness of the approach. PMID:16448020

Singh, Rahul

2004-01-01

406

Laboratory investigations  

NASA Technical Reports Server (NTRS)

Laboratory studies related to cometary grains and the nuclei of comets can be broken down into three areas which relate to understanding the spectral properties, the formation mechanisms, and the evolution of grains and nuclei: (1) Spectral studies to be used in the interpretation of cometary spectra; (2) Sample preparation experiments which may shed light on the physical nature and history of cometary grains and nuclei by exploring the effects on grain emissivities resulting from the ways in which the samples are created; and (3) Grain processing experiments which should provide insight on the interaction of cometary grains with the environment in the immediate vicinity of the cometary nucleus as the comet travels from the Oort cloud through perihelion, and perhaps even suggestions regarding the relationship between interstellar grains and cometary matter. A summary is presented with a different view of lab experiments than is found in the literature, concentrating on measurement techniques and sample preparations especially relevant to cometary dust.

Russell, Ray W.

1988-01-01

407

Virtual Laboratory  

NSDL National Science Digital Library

The website for the Virtual Laboratory contains a bold and direct statement: "Conventional teaching all too often accepts memorization and pattern recognition as true learning" After reading this statement, it makes sense that the goal of this site is "to help students to recognize, confront, correct, and expand their understanding of subject or a technique." The site contains five different sets of course materials that use interactive materials, short quizzes, and embedded demonstrations to assist students and teachers alike. One set of materials that should not be missed is in the Teaching & Learning Biology area. Here visitors will find links, fact sheets, and pedagogical suggestions for teaching a college-level biology course. Moving on, the Chemistry, Life, the Universe and Everything section contains a new perspective on how to reform the garden-variety general chemistry course.

2012-04-27

408

Robust Word Similarity Estimation Using Perturbation Kernels  

Microsoft Academic Search

We introduce perturbation kernels, a new class of similarity measure for information retrieval that casts word similarity in terms of multi-task learning. Perturbation kernels model uncertainty in the user's query by choosing a small number of variations in the relative weights of the query terms to build a more complete picture of the query con- text, which is then used

Kevyn Collins-thompson

2009-01-01

409

Vulnerabilities in similarity search based systems  

Microsoft Academic Search

Similarity based queries are common in several modern database applications, such as multimedia, scientific, and biomedical databases. In most of these systems, database responds with the tuple with the closest match according to some metric. In this paper we investigate some important security issues related to similarity search in databases. We investigate the vulnerability of such systems against users who

Ali Saman Tosun; Hakan Ferhatosmanoglu

2002-01-01

410

Similarity Effects in Short-Term Memory.  

National Technical Information Service (NTIS)

The nature of similarity effects in short-term memory has been a focal point of investigations that attempt to discover fundamental similarities or differences between short-term memory and long-term memory. A conclusion common to many of these experiment...

H. G. Shulman

1969-01-01

411

Similarity indices, sample size and diversity  

Microsoft Academic Search

The effect of sample size and species diversity on a variety of similarity indices is explored. Real values of a similarity index must be evaluated relative to the expected maximum value of that index, which is the value obtained for samples randomly drawn from the same universe, with the diversity and sample sizes of the real samples. It is shown

Henk Wolda

1981-01-01

412

Fingerprint Matching Based on Global Comprehensive Similarity  

E-print Network

Fingerprint Matching Based on Global Comprehensive Similarity Yuliang He, Jie Tian, Senior Member in the representation of a fingerprint. Finally, we model the relationship between transformation and the comprehensive similarity between two fingerprints in terms of histogram for initial parameter estimation. Through

Tian, Jie

413

Perceived Similarity, Proactive Adjustment, and Organizational Socialization  

ERIC Educational Resources Information Center

The present study explores how perceived demographic and attitudinal similarity can influence proactive behavior among organizational newcomers. We propose that newcomers who perceive themselves as similar to their co-workers will be more willing to seek new information or build relationships, which in turn will lead to better long-term…

Kammeyer-Mueller, John D.; Livingston, Beth A.; Liao, Hui

2011-01-01

414

Manipula math with Java : similar figures  

NSDL National Science Digital Library

Teachers can use this applet to give a visual demonstration of the idea of similar triangles or transformations. The applet could be used in whole class demonstrations to introduce the topic or provide varied examples of how different similar triangles can be.

Ies, Inc

2003-01-01

415

Similarity Measures for Short Segments of Text  

Microsoft Academic Search

Measuring the similarity between documents and queries has been extensively studied in information retrieval. Howe ver, there are a growing number of tasks that require computing the similari ty between two very short segments of text. These tasks include query reform ulation, sponsored search, and image retrieval. Standard text similarity meas ures perform poorly on such tasks because of data

Donald Metzler; Susan T. Dumais; Christopher Meek

2007-01-01

416

Interleaving Helps Students Distinguish among Similar Concepts  

ERIC Educational Resources Information Center

When students encounter a set of concepts (or terms or principles) that are similar in some way, they often confuse one with another. For instance, they might mistake one word for another word with a similar spelling (e.g., allusion instead of illusion) or choose the wrong strategy for a mathematics problem because it resembles a different kind of…

Rohrer, Doug

2012-01-01

417

Field Studies versus Laboratory Studies, Degradation Rates  

Microsoft Academic Search

The use of laboratory biodegradation half-lives to predict rates of degradation in the field has been studied in several recent publications. In general, laboratory studies are not accurate predictors of field degradation rates. The reasons for this have included: changes to the soil during preparation steps or storage of the soil, the static conditions of the laboratory study versus dynamic

Philip Howard

418

Gait Signal Analysis with Similarity Measure  

PubMed Central

Human gait decision was carried out with the help of similarity measure design. Gait signal was selected through hardware implementation including all in one sensor, control unit, and notebook with connector. Each gait signal was considered as high dimensional data. Therefore, high dimensional data analysis was considered via heuristic technique such as the similarity measure. Each human pattern such as walking, sitting, standing, and stepping up was obtained through experiment. By the results of the analysis, we also identified the overlapped and nonoverlapped data relation, and similarity measure analysis was also illustrated, and comparison with conventional similarity measure was also carried out. Hence, nonoverlapped data similarity analysis provided the clue to solve the similarity of high dimensional data. Considered high dimensional data analysis was designed with consideration of neighborhood information. Proposed similarity measure was applied to identify the behavior patterns of different persons, and different behaviours of the same person. Obtained analysis can be extended to organize health monitoring system for specially elderly persons. PMID:25110724

Shin, Seungsoo

2014-01-01

419

Surgical Planning Laboratory  

NSDL National Science Digital Library

As a laboratory within the Brigham and Women's Hospital, the Surgical Planning Laboratory (SPL) does research and development in image processing algorithms, software systems, and medical applications. While visitors with an interest in these matters will appreciate the sections of this site that provide details on this work, visitors from the health sciences will also appreciate the educational materials offered in the "Resources" area even more. In the "Training and Tutorials" area, visitors can learn more about medical imaging through a self-paced tutorial. Moving on, the "Image Gallery" area contains over forty medical images that can be useful for those who are looking to learn about identifying various neurological conditions. Finally, the site also has a database of publications created by members of the research team at the SPL.

420

Twin Similarity in Cardiovascular Stress Response  

Microsoft Academic Search

Cardiovascular (CV) responses to laboratory stressors were measured in 12 pairs of identical and 21 pairs of fraternal adult male twins. For this study, blood pressure and heart rate were measured during a mental arithmetic task and the Cold Pressor Test. The analyses of cardiovascular responses to these stressors were designed to test for the presence of a genetic component

Dorit Carmelli; Margaret A. Chesney; Marcia M. Ward; Ray H. Rosenman

1985-01-01

421

Asthma and COPD: Differences and Similarities  

MedlinePLUS

... My Membership About the AAAAI Share | Asthma and COPD: Differences and Similarities This article has been reviewed ... you could have asthma, or you could have Chronic Obstructive Pulmonary Disease (COPD) , such as emphysema or chronic bronchitis. Because ...

422

Semantic Similarity Knowledge and its Applications  

E-print Network

) => edible fruit => produce, green goods, green groceries, garden truck => food => solid => substance, matter, green goods, green groceries, ... #12;6 WordNet::Similarity Software Package http, apricot, peach, nectarine, plum, greengage, damson, cherry; apple, crab apple, pippin, russet, pear

Inkpen, Diana

423

Towards integrative gene functional similarity measurement  

PubMed Central

Background In Gene Ontology, the "Molecular Function" (MF) categorization is a widely used knowledge framework for gene function comparison and prediction. Its structure and annotation provide a convenient way to compare gene functional similarities at the molecular level. The existing gene similarity measures, however, solely rely on one or few aspects of MF without utilizing all the rich information available including structure, annotation, common terms, lowest common parents. Results We introduce a rank-based gene semantic similarity measure called InteGO by synergistically integrating the state-of-the-art gene-to-gene similarity measures. By integrating three GO based seed measures, InteGO significantly improves the performance by about two-fold in all the three species studied (yeast, Arabidopsis and human). Conclusions InteGO is a systematic and novel method to study gene functional associations. The software and description are available at http://www.msu.edu/~jinchen/InteGO. PMID:24564710

2014-01-01

424

Learning Consumer Preferences Using Semantic Similarity  

E-print Network

Learning Consumer Preferences Using Semantic Similarity Reyhan Aydogan reyhan not be readily served by the providers. This requires the service consumers and providers to negotiate consumers and producers use a shared ontology to negotiate a service. Through repetitive interactions

Yolum, Pýnar

425

Self-similarity in Laplacian growth  

SciTech Connect

We consider Laplacian Growth of self-similar domains in different geometries. Self-similarity determines the analytic structure of the Schwarz function of the moving boundary. The knowledge of this analytic structure allows us to derive the integral equation for the conformal map. It is shown that solutions to the integral equation obey also a second-order differential equation which is the 1D Schroedinger equation with the sinh{sup -2}-potential. The solutions, which are expressed through the Gauss hypergeometric function, characterize the geometry of self-similar patterns in a wedge. We also find the potential for the Coulomb gas representation of the self-similar Laplacian growth in a wedge and calculate the corresponding free energy.

Mineev-weinstein, Mark [Los Alamos National Laboratory; Zabrodin, Anton [ITEP, MOSCOW, RUSSIA; Abanov, Artem [TEXAS A & M

2008-01-01

426

The Similarity Index and DNA Fingerprinting  

Microsoft Academic Search

DNA-fingerprint similarity is being used increasingly to make inferences about levels of genetic variation within and between natural populations. It is shown that the similarity index-the average fraction of shared restriction fragments-provides upwardly biased estimates of population homozygosity but nearly unbiased estimates of the average identity-in-state for random pairs of individuals. A method is suggested for partitioning the DNA-fingerprint dissimilarity

Michael Lynch

427

Tool for defining catchment similarity matrix  

NASA Astrophysics Data System (ADS)

It is important to classify catchments for many reasons, for example, for prediction in ungauged basins, model parameterization and watershed development. There have been many studies on catchment classification, but no silver bullet exists for choosing the most relevant measure of catchment similarity. The aim of this study is to explore a new measure of similarity among catchments, using a data depth function. We used a similarity measure called "Depth-Depth plot" (DD-plot) which measures similarity in the catchment flow dynamics in multiple dimension. The area under the convex hull of DD-plot can be used as similarity matrix to any clustering technique. In this study we used Affinity propagation (AP) clustering algorithm for grouping the similar catchments. Catchment classifications based on flow and physical characteristics were compared. We evaluate whether the similarity based on depth-depth plots provides a better basis for transferring parameter sets of a hydrological model between catchments. We used a case study of 21 catchments located in the Bay of Plenty region in the North Island of New Zealand. The catchments have a wide range of topographic properties, response behaviours and geological features. The TopNet hydrological model was calibrated for all the catchments and the transferability of model parameters among the similar catchments was tested by transferring the parameters from within the cluster group and outside the group. The results of parameter transferred with in group based on Nash-Sutcliffe coefficient are promising. Results also show that clustering based on our proposed depth-depth measure, catchment characteristics, flow, and flow indices are different. The catchment classification of this study can be used to improve regional flood forecasting capabilities.

Singh, Shailesh Kumar; McMillan, Hilary; Bárdossy, András; Fateh, Chebana

2014-05-01

428

Context-based Music Similarity Estimation  

Microsoft Academic Search

This review article presents the state-of-the-art in context- based music similarity estimation. It gives an overview of dierent sources of context-based data on music entities and summarizes various ap- proaches for constructing similarity measures based on the collaborative or cultural knowledge that is incorporated in these data sources. The strength of such context-based measures is elaborated as well as their

Markus Schedl; Peter Knees

429

Young children's comprehension of similarities underlying metaphor  

Microsoft Academic Search

The comprehension of similarity by forty-eight 3-, 4-, and 5-year-olds was investigated using a set of binary choice tasks. These tasks were composed of contrasting concepts that were to be matched to conceptually related target stimuli on the basis of relationships underlying object\\/personality metaphor, color\\/personality metaphor, concrete metaphor, taxonomic similarity, and functional association. The youngest children were able to comprehend

Victor Broderick

1991-01-01

430

Similarity Coloring of DTI Fiber Tracts  

Microsoft Academic Search

We present a coloring method that conveys spatial relations between DTI fiber tracts effectively; similar tracts are assigned to similar colors and differ- ent tracts are assigned to different colors in a smooth and continuous manner. To this end, we combine a standard spectral approach with a mass-spring heuristic to embed fiber tracts into a perceptually uniform color space, L*a*b*.

Caùgatay Demiralp; David H. Laidlaw

431

Mining Concept Similarities for Heterogeneous Ontologies  

Microsoft Academic Search

\\u000a We consider the problem of discovering pairs of similar concepts, which are part of two given source ontologies, in which\\u000a each concept node is mapped to a set of instances. The similarity measures we propose are based on learning a classifier for\\u000a each concept that allows to discriminate the respective concept from the remaining concepts in the same ontology. We

Konstantin Todorov; Peter Geibel; Kai-Uwe Kühnberger

2010-01-01

432

Laboratory spectroscopy of HED meteorites  

NASA Astrophysics Data System (ADS)

4 Vesta is one of the largest and the most massive asteroid in the Main Asteroid Belt. This asteroid possesses a basaltic surface and apparently formed and differentiated very early in the history of the solar system. There are strong evidences that indicate Vesta as the parent body of Howardites, Diogenites and Eucrites (HEDs). HED meteorites are a subgroup of achondrite meteorites and they are a suite of rocks that formed at high temperature and experienced igneous processing similar to the magmatic rocks found on Earth. The visible and near-infrared (VNIR) reflectance spectra of Vesta's surface show high similarity with the laboratory spectra of HED meteorites. Vesta and HEDs spectra have two crystal field absorption bands close to 0.9 ?m and 1.9 ?m indicative of the presence of ferrous iron in pyroxenes. The HEDs differ from each other primarily based on variation in pyroxene composition and the pyroxene-plagioclase ratio as well as rocks texture characteristics (e.g., size of crystals). These differences suggest that a combined VNIR spectra studies of Vesta and HED meteorites might reveal the different characteristics of the surface compositions and shed new light on the origin and the thermal history of Vesta. Moreover the link between Vesta and HEDs could provide a test bed to understand the short-lived radionuclide-driven differentiation of planetary bodies. Here we present preliminary result of a study of spectral characteristics of different HED samples, provided to us by the Vatican Observatory. Bidirectional reflectance spectra of slabs of meteorites are performed in the VNIR, between (0.35/2.50) ?m, using a Fieldspec spectrometer mounted on a goniometer, in use at the SLAB (Spectroscopy laboratory, INAF, Rome). The spectra are acquired in standard conditions with an incidence angle i=30o and an emission angle e=0o, measuring a spot with a diameter of 5 mm. Different Howardite, Diogenite and Eucrite samples are "mapped" considering several spots on the surface of the slabs to define th