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1

Conditioned Attraction, Similarity, and Evaluative Meaning.  

National Technical Information Service (NTIS)

Recent S-R formulations have indicated that similarity between persons functions as a UCS and that interpersonal attraction is a classically conditioned evaluative response. The thesis of the present study is that similarity is a correlate of evaluative m...

R. B. Stalling A. Staats

1969-01-01

2

Pathogenesis of Malaria and Clinically Similar Conditions  

PubMed Central

There is now wide acceptance of the concept that the similarity between many acute infectious diseases, be they viral, bacterial, or parasitic in origin, is caused by the overproduction of inflammatory cytokines initiated when the organism interacts with the innate immune system. This is also true of certain noninfectious states, such as the tissue injury syndromes. This review discusses the historical origins of these ideas, which began with tumor necrosis factor (TNF) and spread from their origins in malaria research to other fields. As well the more established proinflammatory mediators, such as TNF, interleukin-1, and lymphotoxin, the roles of nitric oxide and carbon monoxide, which are chiefly inhibitory, are discussed. The established and potential roles of two more recently recognized contributors, overactivity of the enzyme poly(ADP-ribose) polymerase 1 (PARP-1) and the escape of high-mobility-group box 1 (HMGB1) protein from its normal location into the circulation, are also put in context. The pathogenesis of the disease caused by falciparum malaria is then considered in the light of what has been learned about the roles of these mediators in these other diseases, as well as in malaria itself.

Clark, Ian A.; Alleva, Lisa M.; Mills, Alison C.; Cowden, William B.

2004-01-01

3

Similar Cases Retrieval from the Database of Laboratory Test Results  

Microsoft Academic Search

We proposed a suitable method to search similar cases from the laboratory test results database, whose data are basically numerical and ordinal data. We transformed raw data into ordinal ranks and into new scores lying between 0 and 1, then calculated the Mahalanobis distances as a similarity measure. We used 3000 cases of blood count data. In 100 sample cases,

Zhenjun Yang; Yasushi Matsumura; Shigeki Kuwata; Hideo Kusuoka; Hiroshi Takeda

2003-01-01

4

Similar Cases Retrieval From the Database of Laboratory Test Results  

Microsoft Academic Search

We proposed a suitable method to search similar cases from the laboratory test results database, whose data are basically numerical and ordinal data. We transformed raw data into ordinal ranks and into new scores lying between 0 and 1, then calculated the Mahalanobis distances as a similarity measure. We used 3000 cases of blood count data. In 100 sample cases,

Zhenjun Yang; Yasushi Matsumura; Shigeki Kuwata; Hideo Kusuoka; Hiroshi Takeda

2003-01-01

5

42 CFR 493.1441 - Condition: Laboratories performing high complexity testing; laboratory director.  

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; laboratory director...Testing Laboratories Performing High Complexity Testing § 493.1441 Condition: Laboratories performing high complexity testing; laboratory...

2010-10-01

6

Anonymous indexing of health conditions for a similarity measure.  

PubMed

A health social network is an online information service which facilitates information sharing between closely related members of a community with the same or a similar health condition. Over the years, many automated recommender systems have been developed for social networking in order to help users find their communities of interest. For health social networking, the ideal source of information for measuring similarities of patients is the medical information of the patients. However, it is not desirable that such sensitive and private information be shared over the Internet. This is also true for many other security sensitive domains. A new information-sharing scheme is developed where each patient is represented as a small number of (possibly disjoint) d-words (discriminant words) and the d-words are used to measure similarities between patients without revealing sensitive personal information. The d-words are simple words like "food,'' and thus do not contain identifiable personal information. This makes our method an effective one-way hashing of patient assessments for a similarity measure. The d-words can be easily shared on the Internet to find peers who might have similar health conditions. PMID:22531815

Song, Insu; Marsh, Nigel V

2012-04-16

7

42 CFR 493.1403 - Condition: Laboratories performing moderate complexity testing; laboratory director.  

Code of Federal Regulations, 2010 CFR

...Laboratories performing moderate complexity testing; laboratory director...Laboratories Performing Moderate Complexity Testing § 493.1403 Condition: Laboratories performing moderate complexity testing; laboratory...

2010-10-01

8

Erratum: "Similarity criteria for the laboratory simulation of supernova hydrodynamics."  

SciTech Connect

We have discovered an error in one of the numerical examples presented in Table 2 of our paper (p. 828). Specifically, the localization parameter l{sub c}/h for the laboratory experiment, presented in the right-most column of Table 2 should be equal to 2 x 10{sup -6}, and not to 1.1 x 10{sup -8}.

Ryutov, D D; Drake, R P; Kane, J; Liang, E; Remington, B A; Wood-Vasey, W M

2009-04-03

9

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

10

Influence of lubricant additives on rubber properties in conditions similar to the field  

Microsoft Academic Search

Using FTIR spectroscopy, an investigation was performed to establish the oil degradation in a car engine under field conditions. This investigation was used as a baseline to create the laboratory rubber immersion in oil test with aeration. Aeration is required to improve the correlation of the laboratory immersion test with field conditions. The effects of dispersants, corrosion inhibitors and oxidation

Dinzburg

1995-01-01

11

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

12

Conditioning laboratory columns for hysteresis studies  

NASA Astrophysics Data System (ADS)

Evaluating surface area effects on chemical transport properties required estimating the role of hysteresis in the chemical transport processes. To evaluate hysteresis effect unsaturated soil columns at comparable water contents and flow rates were needed. But one column needed to be wetting and a comparable column needed to undergoing drying. Taking advantage of the nearly non-hysteretic behavior in the hydraulic conductivity-water content function, the wetting column was brought to a constant flux rate from a dry condition. The second column was brought to the same flow rate but was started from a wet condition. The apparatus and equilibration times are presented.

Sisson, J. B.; Schaffer, A.

2002-12-01

13

Growth of phototrophic biofilms from limestone monuments under laboratory conditions  

Microsoft Academic Search

In the current study, five phototrophic biofilms from different Southern Europe limestone monuments were characterised by molecular techniques and cultivated under laboratory conditions. Phototrophic biofilms were collected from Orologio Tower in Martano (Italy), Santa Clara-a-Velha Monastery and Ajuda National Palace, both in Portugal, and Seville and Granada Cathedrals from Spain. The biofilms were grown under laboratory conditions and periodically sampled

Ana Zlia Miller; Leonila Laiz; Amlia Dionsio; Maria Filomena Macedo; Cesareo Saiz-Jimenez

2009-01-01

14

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

NASA Astrophysics Data System (ADS)

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 law 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 Lie group theory. The use of the Lie group method appears to be a systematic method which allows us to construct easily and systematically the scaling laws of a given problem. This powerful tool permits us to unify the recent major advances on scaling laws and to identify new similarity concepts that we discuss in this paper, and suggests important applications for present and future laboratory astrophysics experiments. All these results enable us 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 Lie group theory, this paper constitutes the starting point of any analysis of the self-similar dynamics of radiating fluids.

Falize, .; Michaut, C.; Bouquet, S.

2011-04-01

15

29 CFR 1620.18 - Jobs performed under similar working conditions.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Jobs performed under similar working conditions...COMMISSION THE EQUAL PAY ACT § 1620.18 Jobs performed under similar working conditions...for the equal pay standard to apply, the jobs are required to be performed...

2013-07-01

16

The effect of similar and dissimilar conditions upon learning and relearning  

Microsoft Academic Search

The relative efficiency, as measured by the Ebbinghaus saving method, of similar and dissimilar learning and relearning conditions was studied. The conditions used were: (1) a combined auditory and visual stimulation, and (2) a state of relative quiet. No significant differences were found in the percent saved during relearning under the various conditions devised in this experiment. The ability of

J. Pessin

1932-01-01

17

Environmental monitoring programs vs Good Laboratory Practice (GLP) programs: differences and similarities.  

PubMed

Environmental monitoring and Good Laboratory Practice programs are similar when looked at empirically. Both address quality issues, human or environmental safety, and have set procedures to assure the concomitant results. However, when compared at the operational level, they can be best described as very different. Good Laboratory Practice programs deal basically with two governmental agencies and their divisions- the Environmental Protection Agency and Food and Drug Administration. These are administered from the federal level involving no state resources. These programs are objective driven with the procedures being defined in study plans, protocols, and standard operating procedures. The environmental monitoring testing programs deal with a profusion of federal legislation including CERCLA (also known as CLP), RCRA, CWA, CAA, SDWA, NPDES and others. These acts require analysis by specific procedures mandated by the statutes. States operate many of these programs and have been given the authority by the federal government. Many of the states require separate certifications to conduct these analyses. Environmental monitoring testing laboratories often must acquire multiple state certifications to participate in multiple state programs. This is not cost effective and often leads to conflicting requirements. Much of the direction for having a national certification program comes from problems associated with these state-operated programs. PMID:8890354

Bentley, R E

1995-12-01

18

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

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; clinical consultant...Testing Laboratories Performing High Complexity Testing § 493.1453 Condition: Laboratories performing high complexity testing; clinical...

2010-10-01

19

42 CFR 493.1459 - Condition: Laboratories performing high complexity testing; general supervisor.  

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; general supervisor...Testing Laboratories Performing High Complexity Testing § 493.1459 Condition: Laboratories performing high complexity testing; general...

2009-10-01

20

42 CFR 493.1487 - Condition: Laboratories performing high complexity testing; testing personnel.  

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; testing personnel. ...Testing Laboratories Performing High Complexity Testing § 493.1487 Condition: Laboratories performing high complexity testing; testing...

2009-10-01

21

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

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; cytotechnologist. 493...Testing Laboratories Performing High Complexity Testing § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist....

2010-10-01

22

42 CFR 493.1487 - Condition: Laboratories performing high complexity testing; testing personnel.  

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; testing personnel. ...Testing Laboratories Performing High Complexity Testing § 493.1487 Condition: Laboratories performing high complexity testing; testing...

2010-10-01

23

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

Code of Federal Regulations, 2010 CFR

...Condition: Laboratories performing high complexity testing; cytotechnologist. 493...Testing Laboratories Performing High Complexity Testing § 493.1481 Condition: Laboratories performing high complexity testing; cytotechnologist....

2009-10-01

24

Influence of lubricant additives on rubber properties in conditions similar to the field  

SciTech Connect

Using FTIR spectroscopy, an investigation was performed to establish the oil degradation in a car engine under field conditions. This investigation was used as a baseline to create the laboratory rubber immersion in oil test with aeration. Aeration is required to improve the correlation of the laboratory immersion test with field conditions. The effects of dispersants, corrosion inhibitors and oxidation inhibitors containing amine groups on rubber compounds were evaluated in oil with and without aeration. Two rubber base compounds were tested: highly saturated butadiene-nitrile (HNBR) and fluoroelastomer (FKM). The aggressiveness of the inhibitors containing amines was varied and was affected to differing degrees by aeration, water, and type of rubber. 35 refs., 13 figs., 3 tabs.

Dinzburg, B.N. [CR Industries, Elgin, IL (United States)

1995-10-01

25

Anaerobic Biodegradation of Alkylbenzenes in Laboratory Microcosms Representing Ambient Conditions  

Microsoft Academic Search

A microcosm study was performed to document the anaerobic biodegradation of benzene, toluene, ethylbenzene, m- xylene, and\\/or o-xylene in petroleum-contaminated aquifer sediment from sites in Michigan (MI) and North Carolina (NC) and relate the results to previous field investigations of intrinsic bioremediation. Laboratory microcosms, designed to simulate ambient conditions, were constructed under anaerobic conditions with sediment and groundwater from source,

Melody J. Hunt; Michael B. Shafer; Morton A. Barlaz; Robert C. Borden

1997-01-01

26

Cable condition monitoring research activities at Sandia National Laboratories  

Microsoft Academic Search

Sandia National Laboratories is currently conducting long-term aging research on representative samples of nuclear power plant cables. The objectives of the program are to determine the suitability of these cables for extended life (beyond 40 year design basis) and to assess various cable condition monitoring techniques for predicting remaining cable life. The cables are being aged for long times at

M. J. Jacobus; G. L. Zigler; L. D. Bustard

1988-01-01

27

Hydrological conditions at the 800 Area at Argonne National Laboratory  

Microsoft Academic Search

This study examined the hydrological conditions of the glacial till underlying the 800 Area sanitary landfill 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, on the basis of these data, the groundwater movement and migration of potential contaminants in

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

1990-01-01

28

PULMONARY CELL POPULATIONS IN HAMSTERS MAINTAINED UNDER EGYPTIAN LABORATORY CONDITIONS  

EPA Science Inventory

The study was conducted to obtain baseline values for pulmonary cells in golden hamsters (Mesocricetus auratus) bred and maintained under the laboratory conditions of Al-Azhar University in Egypt. An improvised technique is presented for measuring pulmonary cells obtained by lung...

29

The effect of stimulus similarity on the acquisition and extinction of a conditioned response  

Microsoft Academic Search

This study was designed to investigate the effects of the similarity between a reinforced and a nonreinforced stimulus on the acquisition and extinction of a conditioned galvanic skin response (GSR). Five groups of 20 Ss each were given 10 reinforced acquisition trials consisting of a 1-sone, 1967-cps tone followed by a mild shock. Three of the groups were presented 10

Darwin P. Hunt

1962-01-01

30

42 CFR 493.1421 - Condition: Laboratories performing moderate complexity testing; testing personnel.  

Code of Federal Regulations, 2010 CFR

...Laboratories performing moderate complexity testing; testing personnel...Laboratories Performing Moderate Complexity Testing § 493.1421 Condition: Laboratories performing moderate complexity testing; testing...

2009-10-01

31

42 CFR 493.1421 - Condition: Laboratories performing moderate complexity testing; testing personnel.  

Code of Federal Regulations, 2010 CFR

...Laboratories performing moderate complexity testing; testing personnel...Laboratories Performing Moderate Complexity Testing § 493.1421 Condition: Laboratories performing moderate complexity testing; testing...

2010-10-01

32

Self-similarity in the classification of finite-size scaling functions for toroidal boundary conditions.  

PubMed

The conventional periodic boundary conditions in two dimensions are extended to general boundary conditions, prescribed by primitive vector pairs that may not coincide with the coordinate axes. This extension is shown to be unambiguously specified by the twisting scheme. Equivalent relations between different twist settings are constructed explicitly. The classification of finite-size scaling functions is discussed based on the equivalent relations. A self-similar pattern for distinct classes of finite-size scaling functions is shown to appear on the plane that parametrizes the toroidal geometry. PMID:18351807

Liaw, Tsong-Ming; Huang, Ming-Chang; Luo, Yu-Pin; Lin, Simon C; Chou, Yen-Liang; Deng, Youjin

2008-01-02

33

A Laboratory Wood Chipper for Chipping Under Realistic Conditions  

Microsoft Academic Search

Wood chipping is a critical component part of many pulp and paper making processes. In order to study the damage mechanisms,\\u000a when wood chips are created through the wood chipping process, it is crucial to have access to an experimental equipment in\\u000a which chips can be produced under realistic conditions. In this paper, a laboratory chipper is presented, which has

L. M. Hellstrm; P. A. Gradin; M. Gulliksson; T. Carlberg

34

Floor-supply displacement air-conditioning: Laboratory experiments  

SciTech Connect

The results of laboratory measurements on the performance of a floor-supply displacement air-conditioning system in comparison to a displacement ventilation system with a side-wall-mounted diffuser and a ceiling-based distribution system are described. Thermal stratification was observed, as there were greater vertical air temperature differences in both of the displacement systems than in the ceiling-based system. The floor-supply displacement air-conditioning system produced a uniformly low air velocity at each measurement height, while a rather high air velocity near the floor was observed for the displacement ventilation system with a sidewall-mounted diffuser. Local mean age of air of the floor-supply displacement air-conditioning system was lower than that of the other systems, especially in the lower part of the room. According to the simulation results, the floor-supply displacement air-conditioning system with outdoor air cooling requires 34% less energy than the conventional air-conditioning system with outdoor air cooling.

Akimoto, Takashi; Nobe, Tatsuo; Tanabe, Shinichi; Kimura, Kenichi

1999-07-01

35

Red sprite discharges in the atmosphere at high altitude: the molecular physics and the similarity with laboratory discharges  

Microsoft Academic Search

An overview of the general phenomenology and physical mechanism of large-scale electrical discharges termed sprites observed at high altitude in the Earth's atmosphere above thunderstorms is presented. The primary emphasis is placed on summarizing available experimental data on various emissions documented to date from sprites and interpretation of these emissions in the context of similar data obtained from laboratory discharges,

V P Pasko

2007-01-01

36

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 1.31.0 ?g m-3 and 0.210.16 ?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

37

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 1.31.0 ?g m-3 and 0.210.16 ?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

38

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...

39

Self-Similar evolution of Richtmyer-Meshkov instability under re-shock conditions  

NASA Astrophysics Data System (ADS)

The Richtmyer-Meshkov (RM) instability is of critical importance in inertial confinement fusion (ICF) and astrophysics. In the present work a systematic study has been made of the growth of the turbulent mixing zone (TMZ) under re-shock conditions. In this study, shock-tube experiments were done by Leinov et al. [1] changing the re-shock arrival time, by varying the shock-tube end wall distance, as well as the shock Mach number. Using 3D direct numerical simulations as well as 3D bubble-competition model [2], for various initial 3D conditions, it was found that the best agreement with the experimental results is achieved when the TMZ evolution is dominated by the self-similar behavior of the bubble size and amplitude distributions. The TMZ power law at the first and second shock was deducted from the experimental and numerical data and compared with the results of the bubble competition model. [1] E. Leinov et. al. JFM, 626, 449(2009). [2] U. Alon et. al. PRL 72, 2867 (1994); D. Oron et. al. PoP 8, 2883 (2001); D. Kartoon et. al. LPB 21, 327 (2003).

Malamud, Guy; Leinov, Eli; Formoza, Asi; Sadot, Oren; Levin, Arie; Ben-Dor, Gabi; Elbaz, Yonatan; Shvarts, Dov

2011-11-01

40

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

41

Temporal variation of nonstructural carbohydrates in montane conifers: similarities and differences among developmental stages, species and environmental conditions.  

PubMed

Nonstructural carbohydrates (NSCs) are commonly used to assess the balance of carbon sources and sinks in plants. A notable application of this approach has been tests of hypotheses on carbon limitations of trees at their upper altitudinal limits, near the alpine. How NSCs vary in time is not well known in conifers during their critical seedling stage, despite the importance of knowing the temporal variations of NSCs to use snapshot measurements of NSCs to assess carbon balance. We measured NSCs in needles, separately as soluble sugars and starch; (1) over diurnal periods in seedlings of Pseudotsuga menziesii (Mirb.) Franco (a timberline species that does not occur up to treeline), (2) throughout the growth season in the seedlings of P. menziesii and Abies lasiocarpa (Hook.) Nutt. (a species that does occur up to treeline) growing along an elevation gradient in the timberline ecotone and furthermore (3) compared seedlings and co-occurring adults to assess variation with developmental stage. We also compared NSCs in seedlings grown under field or laboratory conditions to separate environmental from intrinsic factors affecting NSCs during early emergence. Diurnal variations in NSCs were minimal, especially when compared to seasonal variation, and were detectable mainly in relatively small midday maxima of soluble sugar concentrations. Seasonal patterns of NSCs were generally (and surprisingly) similar among field and laboratory seedlings and adults. Seasonal patterns of NSCs were dominated by progressive increases in soluble sugars until winter, and by early-season peaks in starch. Nonetheless, notable differences were detectable among ages, species and environmental conditions in (1) the timing and extent of the early-season maxima of starch and (2) the extent of the late-season maxima of soluble sugars. These differences in NSCs likely correspond with ecophysiologically relevant differences in carbon balance that could affect growth and survival of trees growing in the timberline ecotone. PMID:19203971

Bansal, Sheel; Germino, Matthew J

2009-01-28

42

Comparison of meat quality between eland (Taurotragus oryx) and cattle (Bos taurus) raised under similar conditions.  

PubMed

Physical, chemical and sensory characteristics of meat were compared between non-domestic eland (Taurotragus oryx) bulls (n=6) and domestic Fleckvieh (Bos taurus) bulls (n=6) which were finished under controlled conditions of feeding and management. Musculus longissimus lumborum from eland were darker and less yellow in colour, with a higher pH24 and lower contents of intramuscular fat and total collagen, compared to cattle. Contents (mg/100g muscle tissue) and proportions (g/100g of FA determined) of SFA and MUFA were higher (P<0.01) in cattle. Although the proportion of total PUFA were higher (P<0.001) in eland, contents of PUFA were similar between species. Meat from cattle was consistently scored higher (P<0.05) for sensory texture characteristics, juiciness, flavour, and overall acceptance. We concluded that bulls of eland provided low-fat meat with a beneficial fatty acid composition from a human nutrition perspective, but with lower sensory scores, compared to bull beef. PMID:23954274

Barto?, Lud?k; Bure, Daniel; Kotrba, Radim; Sales, James

2013-07-19

43

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

Code of Federal Regulations, 2013 CFR

...1 2013-04-01 2013-04-01 false Commercial gauger and commercial laboratory bond conditions. 113.67 Section...BONDS Customs Bond Conditions § 113.67 Commercial gauger and commercial laboratory bond...

2013-04-01

44

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 25days (range 17-44), whereas males remain after female engorgement on tortoise host. Female pre-oviposition period was 14days (3-31), followed by 24days of oviposition (18-29). Pre-eclosion and eclosion, both together, takes 31days (21-43). Larvae fed 5days (3-9), then molted to nymphs after 17days (12-23). Feeding period of nymphs lasted 7days (5-10), engorged nymphs molted to adults after 24days (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 147days (98-215). PMID:21431927

Sirok, Pavel; Erhart, Jan; Petrelkov, Klra J; Kamler, Martin

2011-03-24

45

42 CFR 493.1441 - Condition: Laboratories performing high complexity testing; laboratory director.  

Code of Federal Regulations, 2012 CFR

...performing high complexity testing; laboratory director...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1441...

2012-10-01

46

42 CFR 493.1403 - Condition: Laboratories performing moderate complexity testing; laboratory director.  

Code of Federal Regulations, 2012 CFR

...performing moderate complexity testing; laboratory director...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1403...

2012-10-01

47

42 CFR 493.1441 - Condition: Laboratories performing high complexity testing; laboratory director.  

Code of Federal Regulations, 2011 CFR

...performing high complexity testing; laboratory director...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1441...

2011-10-01

48

42 CFR 493.1403 - Condition: Laboratories performing moderate complexity testing; laboratory director.  

Code of Federal Regulations, 2011 CFR

...performing moderate complexity testing; laboratory director...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1403...

2011-10-01

49

42 CFR 493.1355 - Condition: Laboratories performing PPM procedures; laboratory director.  

Code of Federal Regulations, 2012 CFR

...CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS AND CERTIFICATION LABORATORY REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing Provider-Performed Microscopy...

2012-10-01

50

A comparative analysis of Painlev, Lax pair, and similarity transformation methods in obtaining the integrability conditions of nonlinear Schrdinger equations  

Microsoft Academic Search

We derive the integrability conditions of nonautonomous nonlinear Schrdinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painlev method. We show that while the Painlev integrability conditions restrict the dispersion, nonlinearity, and dissipation\\/gain coefficients to be space independent and the external potential to be only a

U. Al Khawaja

2010-01-01

51

A comparative analysis of Painleve, Lax pair, and similarity transformation methods in obtaining the integrability conditions of nonlinear Schroedinger equations  

Microsoft Academic Search

We derive the integrability conditions of nonautonomous nonlinear Schroedinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painleve method. We show that while the Painleve integrability conditions restrict the dispersion, nonlinearity, and dissipation\\/gain coefficients to be space independent and the external potential to be only a

Al Khawaja

2010-01-01

52

Development cycle of Panstrongylus rufotuberculatus (Hemiptera: Reduviidae) under laboratory conditions.  

PubMed

Determinant aspects of the development cycle of Panstrongylus rufotuberculatus (Champion, 1899) were evaluated under laboratory conditions. Fertility, duration of life cycle, mortality rate, feeding time, defecation time, thermal reaction time to food source, and volume of blood ingested were studied. From an initial cohort of fifth instars, nine adult pairs were formed, the females of which oviposited 2,338 eggs over 231 d. The eclosion rate was 84.4%; female and male progeny lived 223.56 (14.41) and 180.78 (14.41) d, respectively. The average total life cycle of immature stages (138.82+/-51.42 d) was distributed as egg, 24.22+/-0.42 d; nymph I, 18.94+/-5.15 d; nymph II, 15.80+/-3.29 d; nymph III, 16.55+/-4.36 d; nymph IV, 25.50+/-7.32 d; and nymph V, 36.71+/-2.75 d. Given these values, 2.6 generations per year are possible. Because of its longevity, rapid response to the presence of a host, large volume of blood ingested, and frequent defecation during feeding, this species constitutes a potentially important vector of Chagas' disease in nonendemic rural areas. PMID:15605638

Wolff, Marta; Cuartas, Eliana; Velsquez, Carlos; Jaramillo, Nicols

2004-11-01

53

Light field and water clarity simulation of natural environments in laboratory conditions  

NASA Astrophysics Data System (ADS)

Simulation of natural oceanic conditions in a laboratory setting is a challenging task, especially when that environment can be miles away. We present an attempt to replicate the solar radiation expected at different latitudes with varying water clarity conditions up to 30 m in depth using a 2.5 m deep engineering tank at the University of New Hampshire. The goals of the study were: 1) to configure an underwater light source that produced an irradiance spectrum similar to natural daylight with the sun at zenith and at 60 under clear atmospheric conditions, and 2) to monitor water clarity as a function of depth. Irradiance was measured using a spectra-radiometer with a cosine receiver to analyze the output spectrum of submersed lamps as a function of distance. In addition, an underwater reflection method was developed to measure the diffuse attenuation coefficient in real time. Two water clarity types were characterized, clear waters representing deep, open-ocean conditions, and murky waters representing littoral environments. Results showed good correlation between the irradiance measured at 400 nm to 600 nm and the natural daylight spectrum at 3 m from the light source. This can be considered the water surface conditions reference. Using these methodologies in a controlled laboratory setting, we are able to replicate illumination and water conditions to study the physical, chemical and biological processes on natural and man-made objects and/or systems in simulated, varied geographic locations and environments.

Pe'eri, Shachak; Shwaery, Glenn

2012-05-01

54

The Relationship of Belief Similarity to Attraction Following Conditioning and Generalization of Affect.  

ERIC Educational Resources Information Center

|Most studies of interpersonal attraction and rejection have come to the unremarkable conclusion that persons who are perceived as similar to one's self in beliefs and values are liked better than those perceived as dissimilar. This experiment was designed to vary in an orthogonal design (1) perceived similarity between a subject and another

Geen, Russell G.; Stonner, David

55

Hydrological conditions at the 800 Area at Argonne National Laboratory  

SciTech Connect

This study examined the hydrological conditions of the glacial till underlying the 800 Area sanitary landfill 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, on the basis of 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 800 Area landfill is located on the western edge of ANL, just south of Westgate Road. It has been in operation since 1966 and has been used for the disposal of sanitary, general refuse. From 1969 through 1978, however, substantial quantities of liquid organic and inorganic wastes were disposed of in a French drain'' at the northeast corner of the landfill. The 800 Area landfill is underlain by a silty clay glacial till. Dolomite bedrock underlies the till at an average depth of about 45.6 m. Trace levels of 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. When this report was prepared, no chemical quality analysis have 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. Recommended actions include installation of five new well clusters and one background well, thorough record-keeping, sample collection and analysis during borehole drilling, slug testing to measure hydraulic conductivity, topographic mapping, continued monitoring of groundwater levels and quality, and monitoring of the unsaturated zone. 17 refs., 13 figs., 4 tabs.

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

1990-08-01

56

Comparative bionomics of four populations of Meccus longipennis (Hemiptera: Reduviidae: Triatominae) under laboratory conditions.  

PubMed

The values of biological parameters related to the life cycles of four populations of Meccus longipennis (Reduviidae: Triatominae) were evaluated. Cohorts of each of the four studied populations from different geographical areas of Mexico were maintained under similar laboratory conditions and then compared. The population from El Saucito de Araujo was different from the other three studied populations, which could help explain the secondary importance of M. longipennis in the state of Chihuahua. This paper also supports the proposition that biological traits are important criteria for determining relationships between populations. PMID:23579806

Martnez-Ibarra, Jos Alejandro; Nogueda-Torres, Benjamn; Licn-Trillo, ngel; Villagrn-Herrera, Mara Elena; de Diego-Cabrera, Jos Antonio; Montaez-Valdez, Oziel Dante; Rocha-Chvez, Gonzalo

2013-04-01

57

Mediated conditioning versus retrospective revaluation in humans: the influence of physical and functional similarity of cues.  

PubMed

Two experiments assessed whether similarity between the two elements of a compound would influence the degree of mediated extinction versus recovery from overshadowing in human causal judgements. In both Experiments 1 and 2, we assessed the influence of extinguishing one element of a two-element compound on judgements about the other element. In Experiment 1 we manipulated the physical similarity of the two elements of the compound; in Experiment 2, we used equivalence and distinctiveness pretraining in order to vary their functional similarity. We found that these procedures influenced mediated extinction and recovery from overshadowing as a function of both physical and acquired similarity and distinctiveness, respectively. The implications of these results for previously reported differences between humans and nonprimate animals are discussed. PMID:18609394

Liljeholm, Mimi; Balleine, Bernard W

2008-05-12

58

Self-Similarity of Electric Currents Networking in a Broad Range of Length Scales: from Laboratory to Cosmic Plasmas  

NASA Astrophysics Data System (ADS)

The results of a high-resolution processing, based on techniques of fractal dimension analysis and called a method of multilevel dynamical contrasting [1], of numerous data from laboratory electric discharges (Z-pinch, plasma focus) and observations of cosmic plasmas (including available Hubble Space Telescope data) reveal high degree of self-similarity of plasma structuring in a very broad range of length scales. This covers about thirty orders of magnitude: from micrometer thickness of individual filaments in laboratory discharges to the structures in the universe which resemble networking of electric currents in laboratory plasmas. The results presented illustrate recently suggested [1] generic features of electric current networking in plasmas: (1) long-living filamentation of electric current; (2) formation of a fractal structures made of a single filament and complicated interaction of these "fractal" filaments; (3) formation of a percolating network that includes, in particular, formation of a "stocking" woven by the individual filaments. [1] Kukushkin A.B., Rantsev-Kartinov V.A., Laser and Particle Beams, 16(3) 1998 (to be published).

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

1998-11-01

59

International Intercomparison of Environmental Dosimeters under Field and Laboratory Conditions.  

National Technical Information Service (NTIS)

Based on the results of a pilot study at ORNL in 1973, a more comprehensive international intercomparison of integrating dosimeters for the assessment of external penetrating environmental radiation fields was carried out. Forty-one laboratories from elev...

T. F. Gesell G. de Planque Burke K. Becker

1975-01-01

60

A comparative analysis of Painleve, Lax pair, and similarity transformation methods in obtaining the integrability conditions of nonlinear Schroedinger equations  

SciTech Connect

We derive the integrability conditions of nonautonomous nonlinear Schroedinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painleve method. We show that while the Painleve integrability conditions restrict the dispersion, nonlinearity, and dissipation/gain coefficients to be space independent and the external potential to be only a quadratic function of position, the Lax Pair and the similarity transformation methods allow for space-dependent coefficients and an external potential that is not restricted to the quadratic form. The integrability conditions of the Painleve method are retrieved as a special case of our general integrability conditions. We also derive the integrability conditions of nonautonomous nonlinear Schroedinger equations for two- and three-spacial dimensions.

Al Khawaja, U. [Department of Physics, United Arab Emirates University, P.O. Box 17551, Al-Ain (United Arab Emirates)

2010-05-15

61

REtools: A laboratory program for restriction enzyme work: enzyme selection and reaction condition assistance  

PubMed Central

Background Restriction enzymes are one of the everyday tools used in molecular biology. The continuously expanding panel of known restriction enzymes (several thousands) renders their optimal use virtually impossible without computerized assistance. Several manufacturers propose on-line sites that assist scientists in their restriction enzyme work, however, none of these sites meet all the actual needs of laboratory workers, and they do not take into account the enzymes actually present in one's own laboratory. Results Using FileMaker Pro, we developed a stand-alone application which can run on both PCs and Macintoshes. We called it REtools, for Restriction Enzyme tools. This program, which references all currently known enzymes (>3500), permits the creation and update of a personalized list of restriction enzymes actually available in one's own laboratory. Upon opening the program, scientists will be presented with a user friendly interface that will direct them to different menus, each one corresponding to different situations that restriction enzyme users commonly encounter. We particularly emphasized the ease of use to make REtools a solution that laboratory members would actually want to use. Conclusion REtools, a user friendly and easily customized program to organize any laboratory enzyme stock, brings a software solution that will make restriction enzyme use and reaction condition determination straightforward and efficient. The usually unexplored potential of isoschizomers also becomes accessible to all, since REtools proposes all possible enzymes similar to the one(s) chosen by the user. Finally, many of the commonly overlooked subtleties of restriction enzyme work, such as methylation requirement, unusual reaction conditions, or the number of flanking bases required for cleavage, are automatically provided by REtools.

Martin, Patrick; Boulukos, Kim E; Pognonec, Philippe

2006-01-01

62

Exposure to tebuconazol in rice field and laboratory conditions induces oxidative stress in carp (Cyprinus carpio).  

PubMed

Pesticides can have an effect on the biochemical and physiological functions of living organisms. The changes seen in fish and their response to pesticides can be used as an example for vertebrate toxicity. In this study, carp fish (Cyprinus carpio) were exposed to different concentrations of tebuconazol fungicide, by rice field (31.95 ?g/L) and laboratory (33.47 and 36.23 ?g/L) conditional testing, during a 7 day period. Parameters such thiobarbituric acid-reactive substance levels (TBARS), protein carbonyl, catalase, glutathione S-transferase and acetylcholinesterase activities were studied, using the liver, brain and white muscle of the fish. The field experiment showed that the TBARS levels were increased in all the analyzed tissues. Similarly, the protein carbonyl of the liver and the brain AChE activity increased after 7 days. The laboratory experiment demonstrated that the TBARS levels in the liver were increased in both of the concentration tests. TBARS levels in the muscle increased only by the lowest test concentration. On the other hand, the protein carbonyl was increased only by the highest concentration. The results indicate that the tebuconazol exposure from the field and laboratory conditions directly affected the health of the fish, showing the occurrence of oxidative stress. PMID:20888428

Toni, Cndida; Loro, Vania Lucia; Santi, Adriana; de Menezes, Charlene Cavalheiro; Cattaneo, Roberta; Clasen, Brbara Estevo; Zanella, Renato

2010-10-01

63

Biodegradation of Fuel Oil Under Laboratory and Arctic Marine Conditions  

Microsoft Academic Search

The aerobic biodegradation of the components of a fuel oil under Arctic summer conditions follows a pattern that is indistinguishable from that exhibited under temperate conditions. Straight chain alkanes and small aromatics are degraded first, followed by branched alkanes and larger and alkylated aromatics. We present data on the biodegradation of heptadecane as a representative n-alkane, pristane as a representative

Robert M Garrett; Stephen J Rothenburger; Roger C Prince

2003-01-01

64

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

65

42 CFR 416.49 - Condition for coverage-Laboratory and radiologic services.  

Code of Federal Regulations, 2012 CFR

...MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) AMBULATORY SURGICAL SERVICES Specific Conditions for Coverage § 416.49 Condition for coverageLaboratory and radiologic services....

2012-10-01

66

Earlier research work on tharparkar and sindh barrage, and similar studies related to demographic, social and economic conditions  

Microsoft Academic Search

This study is earlier research works done on Tharparkar and Sindh barrage, and similar studies related to demographic, social and economic conditions and chapter-2 as a literature review of the thesis of Ph.D submitted in 2002. Purpose of the chapter was to give the complete picture of both areas and at national and international level to support the primary data

Gobind M. Herani

2008-01-01

67

Laboratory conditions and safety in a chemical warfare agent analysis and research laboratory.  

PubMed

Toxic chemicals have been used as weapons of war and also as means of terrorist attacks on civilian populations. Research focusing on chemical warfare agents (CWAs) may be associated with an increased risk of exposure to and contamination by these agents. This article summarizes some of the regulations concerning designation and safety in a CWA analysis and research laboratory and medical countermeasures in case of an accidental exposure. The design of such a laboratory, coupled with a set of safety guidelines, provides for the safe conduct of research and studies involving CWAs. Thus, a discussion of decontamination and protection means against CWAs is also presented. PMID:12188231

Kenar, Levent; Karayilano?lu, Turan; Kose, Songul

2002-08-01

68

Organically bound tritium in wheat after short-term exposure to atmospheric tritium under laboratory conditions  

Microsoft Academic Search

The uptake, loss, conversion and translocation of tritium in wheat plants were determined following a unique short-time exposure to atmospheric tritium under laboratory conditions. Potted plants were exposed between anthesis and maturity, under day-time conditions at two different light intensities and during night conditions. Two data sets with exposure conditions and corresponding tritium concentrations in plants are given for use

S. Diabat; S. Strack

1997-01-01

69

Activity rhythms and masking response in the diurnal fat sand rat under laboratory conditions.  

PubMed

Daily rhythms are heavily influenced by light in two major ways. One is through photic entrainment of a circadian clock, and the other is through a more direct process, referred to as masking. Whereas entraining effects of photic stimuli are quite similar in nocturnal and diurnal species, masking is very different. Laboratory conditions differ greatly from what is experienced by individuals in their natural habitat, and several studies have shown that activity patterns can greatly differ between laboratory environment and natural condition. This is especially prevalent in diurnal rodents. We studied the daily rhythms and masking response in the fat sand rat (Psammomys obesus), a diurnal desert rodent, and activity rhythms of Tristram's jird (Meriones tristrami), a nocturnal member of the same subfamily (Gerbillinae). We found that most sand rats kept on a 12?h:12?h light-dark (LD) cycles at two light intensities (500 and 1000?lux) have a nocturnal phase preferences of general activity and higher body temperature during the dark phase. In most individuals, activity was not as stable that of the nocturnal Tritram's jirds, which showed a clear and stable nocturnal activity pattern under the same conditions. Sand rats responded to a 6-h phase advance and 6-h phase delay as expected, and, under constant conditions, all tested animals free ran. In contrast with the nocturnal phase preference, fat sand rats did not show a masking response to light pulses during the dark phase or to a dark pulse during the light phase. They did, however, have a significant preference to the light phase under a 3.5?h:3.5?h LD schedule. Currently, we could not identify the underlying mechanisms responsible for the temporal niche switch in this species. However, our results provide us with a valuable tool for further studies of the circadian system of diurnal species, and will hopefully lead us to understanding diurnality, its mechanisms, causes, and consequences. PMID:23926956

Barak, Orly; Kronfeld-Schor, Noga

2013-08-08

70

Yersinia pestis infection and laboratory conditions alter flea-associated bacterial communities.  

PubMed

We collected Oropsylla montana from rock squirrels, Spermophilus varigatus, and infected a subset of collected fleas with Yersinia pestis, the etiological agent of plague. We used bar-tagged DNA pyrosequencing to characterize bacterial communities of wild, uninfected controls and infected fleas. Bacterial communities within Y. pestis-infected fleas were substantially more similar to one another than communities within wild or control fleas, suggesting that infection alters the bacterial community in a directed manner such that specific bacterial lineages are severely reduced in abundance or entirely eliminated from the community. Laboratory conditions also significantly altered flea-associated bacterial communities relative to wild communities, but much less so than Y. pestis infection. The abundance of Firmicutes decreased considerably in infected fleas, and Bacteroidetes were almost completely eliminated from both the control and infected fleas. Bartonella and Wolbachia were unaffected or responded positively to Y. pestis infection. PMID:22895162

Jones, Ryan T; Vetter, Sara M; Montenieiri, John; Holmes, Jennifer; Bernhardt, Scott A; Gage, Kenneth L

2012-08-16

71

Laboratory study of frazil ice accumulation under wave conditions  

NASA Astrophysics Data System (ADS)

Ice growth in turbulent seawater is often accompanied by the accumulation of frazil ice crystals at its surface. The thickness and volume fraction of this ice layer play an important role in shaping the gradual transition from a loose to a solid ice cover, however, observations are very sparse. Here we analyse an extensive set of observations of frazil ice, grown in two parallel tanks with controlled wave conditions and thermal forcing, focusing on the first one to two days of grease ice accumulation. The following unresolved issues are addressed: (i) at which volume fraction the frazil crystal rising process starts and how densely they accumulate at the surface, (ii) how the grease ice solid fraction evolves with time until solid ice starts to form and (iii) how do these conditions affect, and are affected by, waves and heat loss from the ice. We obtained estimates of the initial frazil ice solid fraction (0.04-0.05), the maximum solid fraction to which it accumulates (0.24-0.28), as well as the time-scale of packing, at which 95 % of the frazil reaches the maximum solid fraction (12-18 h). Comparison of ice thickness and wave observations also indicates that grease ice first begins to affect the wave field significantly when its thickness exceeds the initial wave amplitude. These results are relevant for modelling frazil ice accumulation and freeze-up of leads, polynyas and the seasonal ice zone.

de La Rosa, S.; Maus, S.

2011-07-01

72

Laboratory study of frazil ice accumulation under wave conditions  

NASA Astrophysics Data System (ADS)

Ice growth in turbulent seawater is often accompanied by the accumulation of frazil ice crystals at its surface, forming a grease ice layer. The thickness and volume fraction of this ice layer play an important role in shaping the gradual transition from a loose to a solid ice cover, however, observations are very sparse. Here we analyse an extensive set of observations of frazil ice, grown in two parallel tanks with controlled wave conditions and thermal forcing, focusing on the first one to two days of grease ice accumulation. The following unresolved issues are addressed: (i) at which volume fraction the frazil crystals' rising process starts and how densely they accumulate at the surface, (ii) how the grease ice solid fraction and salinity evolve with time until solid ice starts to form and (iii) how do these conditions affect, and are affected by, waves and heat loss from the ice. We obtained estimates of the minimum initial grease ice solid fraction (0.03-0.05) and the maximum solid fraction to which it accumulates before freezing into pancakes (0.23-0.31). The equivalent thickness of solid ice that needs to be accumulated until grease ice packs close to maximum (95% of the compaction accomplished), was estimated as 0.4 to 1.2 cm. Comparison of grease ice thickness and wave observations indicates that a grease ice layer first begins to affect the wave field significantly when its thickness exceeds the initial wave amplitude. These results are relevant for modelling frazil ice accumulation and freeze-up of leads, polynyas and along the seasonal ice zone.

de La Rosa, S.; Maus, S.

2012-02-01

73

Resin-based composite light-cured properties assessed by laboratory standards and simulated clinical conditions.  

PubMed

SUMMARY The following parameters were varied: 1) irradiation technique: top and bottom polymerization according to the ISO standard, and polymerization from only the top, simulating clinical situations; 2) polymerization time: 5, 10, 20, and 40 seconds; 3) storage conditions: 24 hours in distilled water, thermocycling followed by storage for four weeks in artificial saliva or alcohol. Flexural strength (FS), flexural modulus (Eflexural), indentation modulus (E), Vickers hardness (HV), and degree of conversion (DC) were measured. The laboratory results were similar to those measured by mimicking clinical conditions only at high polymerization times and mild storage conditions (20 seconds and 40 seconds and storage for 24 hours in water, and 40 seconds with aging and storing in saliva). Significantly higher DC values were measured on the top than on the bottom of a 2-mm layer for all polymerization times. Overall, 5-second and 10-second irradiation times induced significantly lower DC values compared to the currently recommended polymerization times of 20 and 40 seconds at both the top and bottom of the samples. The initial DC differences as a function of irradiation time are leveled at 24 hours of storage but seem to do well in predicting long-term material behavior. A minimum irradiation time of 20 seconds is necessary clinically to achieve the best mechanical properties with modern high-intensity light emitting diode (LED) units. PMID:22788727

Ilie, N; Bauer, H; Draenert, M; Hickel, R

2012-07-11

74

SOLERAS - Saudi University Solar Cooling Laboratories Project: University of Riyadh. Solar air conditioning. Final report  

SciTech Connect

Research on solar air conditioning at the University of Riyadh in Riyhadh, Saudi Arabia is presented. Topics relevant to the university's proposed solar cooling laboratory are discussed: absorption systems and various contingencies, photovoltaic solar collectors and thermoelectric elements, measuring instruments, solar radiation measurement and analysis, laboratory specifications, and decision theories. Dual cycle computations and equipment specifications are included among the appendices.

Not Available

1986-01-01

75

Degradation Studies of Fenazaquin in Soil under Field and Laboratory Conditions  

Microsoft Academic Search

Degradation of fenazaquin in sandy loam soil was investigated under field and laboratory conditions. Fenazaquin (Magister\\u000a 10EC) was applied @ 125 and 250g a.i.\\/ha in field and in pot under field capacity moisture in laboratory. Samples drawn periodically\\u000a were analyzed on GC-NPD. The residues of fenazaquin in both the doses and conditions dissipated almost 90% in 90days. Half-life\\u000a period were

Anil Duhan; Beena Kumari

2011-01-01

76

Laboratory measurements of charge separation in low liquid water content conditions and low impact velocity  

NASA Astrophysics Data System (ADS)

A laboratory investigation of the electric charge separated in collisions between vapor-grown ice crystals and a target growing by riming is presented in this work, with the goal of studying the performance of the noninductive mechanism under microphysical conditions similar to some of those which occur in the stratiform regions of the mesoscale convective systems. A series of experiments were conducted by using a target of 2 mm in diameter, for ambient temperatures between -7C and -13C, effective liquid water content between 0.05 and 0.5 g m-3, and air speeds between 1 and 3 m s-1. Charge diagrams of the sign of the electric charge transfer on the rimer as a function of the ambient temperature and the effective liquid water content for each velocity are presented. The results show that the riming target charges positive for temperatures above -10C. For temperatures below -10C, the charging is positive for high liquid water content and negative for low liquid water content. The magnitude of the charge transfer per collision under the studied conditions ranges from 0.01 to 0.2 fC. The implications of these results to the electrification processes are discussed.

Vila, Eldo E.; Lighezzolo, Rafael A.; Castellano, Nesvit E.; Pereyra, Rodolfo G.; Brgesser, Rodrigo E.

2013-06-01

77

Degradation studies of fenazaquin in soil under field and laboratory conditions.  

PubMed

Degradation of fenazaquin in sandy loam soil was investigated under field and laboratory conditions. Fenazaquin (Magister 10EC) was applied @ 125 and 250g a.i./ha in field and in pot under field capacity moisture in laboratory. Samples drawn periodically were analyzed on GC-NPD. The residues of fenazaquin in both the doses and conditions dissipated almost 90% in 90days. Half-life period were 32.04 and 31.35days at two doses, respectively at field conditions and 30.10 and 28.94days at laboratory conditions. Dissipation was approximated to first order kinetics in both conditions having correlation coefficient ranging from -0.9848 to -0.9914. PMID:21667312

Duhan, Anil; Kumari, Beena

2011-06-12

78

Similar, and similar concepts  

Microsoft Academic Search

This paper analyzes English symmetrical predicates such as collide and match. Its point of departure is an analysis of the concept similar from Tversky (1977) that appears to show that similarity is psychologically asymmetrical. One basis for this claim from Tversky is that the sentences North Korea is similar to Red China and Red China is similar to North Korea

Lila R. Gleitman; Henry Gleitman; Carol Miller; Ruth Ostrin

1996-01-01

79

42 CFR 493.1771 - Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories.  

Code of Federal Regulations, 2010 CFR

...Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories. 493.1771 Section 493...Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories....

2010-10-01

80

42 CFR 493.1771 - Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories.  

Code of Federal Regulations, 2010 CFR

...Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories. 493.1771 Section 493...Condition: Inspection requirements applicable to all CLIA-certified and CLIA-exempt laboratories....

2009-10-01

81

Impacts of six bt rice lines on nontarget rice feeding thrips under laboratory and field conditions.  

PubMed

Nontarget impacts of six transgenic Bt rice lines (expressing the Cry1Ab or Cry1Ab/Cry1Ac protein) on the thrips, Stenchaetothrips biformis (Bagnall), attacking the rice seedling and tillering stages, were evaluated under laboratory and field conditions. Laboratory results showed relatively longer larval, pupal development and preoviposition durations of S. biformis. Although it had a shorter oviposition period, female adult longevity and less total laid eggs were found when fed on some tested Bt rice in comparison to non-Bt controls. S. biformis population dynamics in Bt and non-Bt plots were monitored using the plastic bag and beat plate methods. In the field, the temporal patterns of S. biformis population changes were similar between tested Bt rice lines and their respective control; however, the total number of S. biformis individuals collected from the Bt plots were significantly less or the same, varying from variety to variety, compared with those from the non-Bt plots. ELISA results showed that the Bt insecticidal protein could be transferred from Bt rice to the thrips, and the concentrations of the protein in rice leaves and thrips were not significantly correlated with some important biological parameters of the thrip. In addition, the potential effects of Bt rice on the abundance of S. biformis candidate predators are also discussed. In conclusion, our results show that the six Bt rice lines assessed may be less preferable host plants to S. biformis at the individual and population levels in comparison to the non-Bt rice plants. PMID:20388307

Akhtar, Z R; Tian, J C; Chen, Y; Fang, Q; Hu, C; Chen, M; Peng, Y F; Ye, G Y

2010-04-01

82

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.

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

2000-01-01

83

An assessment of Hyalella azteca burrowing activity under laboratory sediment toxicity testing conditions.  

PubMed

Burrowing of the freshwater amphipod Hyalella azteca was evaluated under laboratory conditions similar to those recommended for standard sediment toxicity testing in Canada (EPS 1/RM/33; Environment Canada, 1997) and the United States (EPA/600/R-99/064; US EPA, 2000). Sediment type, time of day (light versus dark), size of animal, and the presence or absence of food were varied to assess their effects on burrowing activity. Hyalella azteca were found to burrow rapidly in fine, organic-rich sediments, but were slower to burrow in a sandy sediment. There was no increase in the number of animals occupying the sediment surface of a fine, organic-rich sediment after 4h of darkness compared to the previous 4h of light. Over a 9- to 10-d duration, a higher percentage of animals occupied the surface of the sandy sediment. The addition of food promoted burrowing in sandy sediment, as did using smaller animals. Overall, longer-duration tests involving older animals and coarse sediments may require formal observation to confirm burrowing and ensure adequate sediment exposure. The addition of food during a test may promote the burrowing of larger animals in coarse sediments, but may not be necessary in field-collected sediments that are not excessively sandy. PMID:20591466

Doig, Lorne E; Liber, Karsten

2010-06-29

84

Rapid degradation of alkanethiol-based self-assembled monolayers on gold in ambient laboratory conditions  

NASA Astrophysics Data System (ADS)

Self-assembled monolayers (SAMs) consisting of alkanethiols and similar sulfur-containing molecules on noble metal substrates are extensively used and explored for various chemical and biological surface-functionalization in the scientific community. SAMs consisting of thiol- or disulfide-containing molecules adsorbed on gold are commonly used due to their ease of preparation and stability. However, the gold thiolate bond is easily and rapidly oxidized under ambient conditions, adversely affecting SAM quality and structure. Here, the oxidation of dodecanethiol on gold is explored for various 12-h exposures to ambient laboratory air and light. SAM samples are freshly prepared, air-exposed, and stored in small, capped vials. X-ray photoelectron spectroscopy (XPS) reveals nearly complete oxidation of the thiolate in air-exposed samples, and a decrease in carbon signal on the surface. Near-edge X-ray absorption fine structure spectroscopy (NEXAFS) at the carbon K-edge shows a loss of upright orientational order upon air exposure. Alternatively, the oxidation of the thiolate is minor when SAMs are stored in limited-air-containing small 15 ml vials. Thus, care must be taken to avoid SAM degradation by ensuring alkanethiolates on gold have sufficient durability for each intended environment and application.

Willey, Trevor M.; Vance, Andrew L.; van Buuren, T.; Bostedt, C.; Terminello, L. J.; Fadley, C. S.

2005-02-01

85

Self-formed Dynamic Meandering Rivers and Floodplains in the Laboratory: Necessary and Sufficient Conditions  

NASA Astrophysics Data System (ADS)

Traditionally, rivers were downscaled to the laboratory through similarity of the Froude, Shields and Reynolds numbers. This has worked well for rivers with fixed banks and for braided gravel-bed rivers. However, for self-formed dynamic meandering rivers in experiments, Froude scaling is incomplete without a constrained width-depth ratio. This aspect ratio should be small enough to obtain alternate bars. Bank erosion and bar migration have to be limited by somewhat cohesive or vegetated self-formed floodplains. Our objective is to determine the conditions that lead to river meandering in the laboratory. We developed an experimental scaling strategy for meandering gravel-bed rivers that reduces scale problems or quantifies scale effects. A sediment mixture ranging from silt to fine gravel produces subcritical to critical flow, a hydraulically rough boundary without scour holes or current ripples. Furthermore the mixture leads to richer morphodynamics with measurable sorting trends, narrower channels and cohesive self-formed floodplains. We cycle the inflow point of constant flow discharge and sediment feed in transverse direction at the upstream boundary to perturb an initially straight channel and simulate a meander migrating into the flume (Van Dijk et al., this conference). The downstream boundary is a lake into which the river progrades a branched fan delta (Villiers et al., Cheshier et al., van de Lageweg et al., this conference). Morphology was recorded by high-resolution line-laser scanning and digital photography allowed image segmentation and particle size estimation through an entropy method. In agreement with earlier work, the experimental river initially evolves from alternate bars to a fully braided river without significant floodplain building. With silica flour added to the feed, a transitional river between braided and meandering evolves with frequent chute cut-offs but mostly single-thread. During chute cut-offs the water and bed levels upstream of the cut-off location rises, so modest levees and crevasse splays are built and former channels are flooded, though usually not reactivated. After applying floods laden with silica flour to build the floodplain; the river evolved to, on average, a much less mobile single channel with infrequent chute cut-offs. The lateral channel migration rate decreases with increased floodplain building in agreement with natural systems (Lavooi et al., this conference). Ongoing work quantifies the effect of migration rate and amplitude of the inflow position on the morphodynamics and channel pattern. We conclude that necessary and sufficient conditions for a self-formed, dynamically meandering channel in the laboratory are the presence of floods and floodplain-building sediment and a dynamic boundary condition simulating meander migration. In smaller-scale pilot experiments we use different vegetation species and controlled conditions allow adjustable growth rate, bank strength and hydraulic resistance (van Breemen et al., this conference). We will apply this in the large-scale experiment next year to be able to use less silica flour yet inhance floodplain formation.

Kleinhans, M. G.; van Dijk, W. M.; van de Lageweg, W. I.; Markies, H.; van der Gon-Netscher, T.; van de Meer, H.; van Maarseveen, M.; Postma, G.

2010-12-01

86

Acquisition of polarized-light orientation in salmonids under laboratory conditions  

Microsoft Academic Search

We examined orientation responses of juvenile salmonids to a polarized-light stimulus under laboratory conditions. Juvenile rainbow trout, Oncorhynchus mykiss, steelhead (anadromous), O.mykiss, and brook char, Salvelinus fontinalis, were trained using an operant conditioning methodology to orient relative to the axis of a linear-polarized light field. On average, rainbow trout responded correctly relative to the orientation of the light stimulus approximately

Daryl C. Parkyn; James D. Austin; Craig W. Hawryshyn

2003-01-01

87

The local lymph node assay: results of a final inter-laboratory validation under field conditions.  

PubMed

The local lymph node assay (LLNA) assesses the sensitizing activity of chemicals by measurement of primary lymphocyte proliferation in lymph nodes draining the site of application. In this final inter-laboratory study the consistency of LLNA results between laboratories and with guinea pig maximization test (GPMT) data was examined under 'field' conditions. Nine chemicals were evaluated independently by each laboratory according to guidelines for test concentration and vehicle selection developed during previous validation studies to ensure assay optimization. Equivalent predictions of sensitization potential were obtained by all laboratories for eight chemicals. Five of seven chemicals identified as sensitizers in the GPMT were correctly identified in the LLNA--four by all laboratories and 1 (4-chloroaniline) by one laboratory only--although in this latter case, two other laboratories obtained clear dose responses, suggestive of sensitization. The LLNA identified correctly those chemicals predicted to be extreme or strong sensitizers in the GPMT. The remaining two chemicals were non-sensitizers in the guinea pig and failed to elicit positive proliferative responses in the LLNA. These data demonstrate that sensitivity and reliability of the LLNA is retained when chemicals are evaluated independently, and that it provides a reliable pre-screen for the identification of chemicals with significant sensitization potential. PMID:1629518

Scholes, E W; Basketter, D A; Sarll, A E; Kimber, I; Evans, C D; Miller, K; Robbins, M C; Harrison, P T; Waite, S J

1992-06-01

88

Pineal Melatonin in Syrian Hamsters: Circadian and Seasonal Rhythms in Animals Maintained under Laboratory and Natural Conditions  

Microsoft Academic Search

The object of the following study was to compare pineal melatonin rhythms of hamsters housed in outdoor versus laboratory conditions during five consecutive seasons. For each season, 72 adult male Syrian hamsters were caged under controlled laboratory conditions and 72 were caged in a three-sided shelter outdoors. The light:dark cycle for the animals kept in the laboratory approximated the corresponding

George C. Brainard; Larry J. Petterborg; Bruce A. Richardson; Russel J. Reiter

1982-01-01

89

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

Microsoft Academic Search

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

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

1990-01-01

90

The Effect of SpeechEasy on Stuttering Frequency in Laboratory Conditions  

ERIC Educational Resources Information Center

|The effect of SpeechEasy on stuttering frequency during speech produced in a laboratory setting was examined. Thirteen adults who stutter participated. Stuttering frequencies in two baseline conditions were compared to stuttering frequencies with the device fitted according to the manufacturer's protocol. The fitting protocol includes

Armson, Joy; Kiefte, Michael; Mason, Jessica; De Croos, Dayani

2006-01-01

91

Oxycom Under Field and Laboratory Conditions Increases Resistance Responses in Plants  

Microsoft Academic Search

Several different types of chemicals induce resistance in plants. Oxycom that contains active oxygen species has under commercial field conditions improved the performance of a diversity of plant species exposed to a range of naturally-occurring pathogens, including Pythium, downy mildew and powdery mildew. Oxycom had only weak antifungal activity when assayed in the laboratory at the concentrations showing efficacy in

Y. C. Kim; K. A. Blee; J. Robins; A. J. Anderson

2001-01-01

92

Self-formed Dynamic Meandering Rivers and Floodplains in the Laboratory: Necessary and Sufficient Conditions  

Microsoft Academic Search

Traditionally, rivers were downscaled to the laboratory through similarity of the Froude, Shields and Reynolds numbers. This has worked well for rivers with fixed banks and for braided gravel-bed rivers. However, for self-formed dynamic meandering rivers in experiments, Froude scaling is incomplete without a constrained width-depth ratio. This aspect ratio should be small enough to obtain alternate bars. Bank erosion

M. G. Kleinhans; W. M. van Dijk; W. I. van de Lageweg; H. Markies; T. van der Gon-Netscher; H. van de Meer; M. van Maarseveen; G. Postma

2010-01-01

93

A comparative analysis of Painleve, Lax pair, and similarity transformation methods in obtaining the integrability conditions of nonlinear Schrodinger equations  

Microsoft Academic Search

We derive the integrability conditions of nonautonomous nonlinear Schrodinger equations using the Lax pair and similarity transformation methods. We present a comparative analysis of these integrability conditions with those of the Painleve method. We show that while the Painleve integrability conditions restrict the dispersion, nonlinearity, and dissipation\\/gain coefficients to be space independent and the external potential to be only a

U. Al Khawaja

2010-01-01

94

Growth and condition of post-moult male snow crab ( Chionoecetes opilio) in the laboratory  

Microsoft Academic Search

We monitored soft-shell and hard-shell legal-sized male snow crabs sampled periodically in the field or fed to satiation at 4.5 C in the laboratory for changes in nutritional condition. In soft-shell crabs, feeding resulted in a significant decrease of water content in all tissues. This decrease was associated with increased lipid (digestive gland) and protein (muscle and haemolymph) contents. The

Guillaume Godbout; Jean-Denis Dutil; Daniel Hardy; Jean Munro

2002-01-01

95

Verification of Bohr's frequency condition and Moseley's law: An undergraduate laboratory experiment  

Microsoft Academic Search

We describe an undergraduate laboratory experiment to verify Bohr's frequency condition and Moseley's law using a thin NaI(Tl) detector spectrometer and a weak 57Co source. The slope of the plot of Kalpha x-ray energy versus (Z-1)2 yields a value for the Rydberg constant, R=(1.19+\\/-0.01)107 m-1, which is in fair agreement with the best literature value, R=10 973 731.534(13) m-1.

S. B. Gudennavar; N. M. Badiger; S. R. Thontadarya; B. Hanumaiah

2003-01-01

96

Comparison of three models of actigraph accelerometers during free living and controlled laboratory conditions  

Microsoft Academic Search

The aim of this study was to compare the outputs of three commonly used uniaxial Actigraph models (Actitrainer, 7164 and GT1M) under both free-living and controlled laboratory conditions. Ten adults (mean age = 24.71.1 years) wore the three Actigraph models simultaneously during one of day free-living and during a progressive exercise protocol on a treadmill at speeds between 1.5 and

Ka-Yiu Lee; Duncan J. Macfarlane; Ester Cerin

2012-01-01

97

Larval Culture of Tachypleus gigas and Its Molting Behavior Under Laboratory Conditions  

Microsoft Academic Search

\\u000a Horseshoe crab populations along the northeast coast of India are under threat due to degradation of the breeding beaches.\\u000a To augment the trend, attempts were made to culture the larvae of Tachypleus gigas and study its growth rate by enhancing the molting pattern in the laboratory condition. Trilobites of T. gigas were cultured on a controlled diet of brine shrimp

J. K. Mishra

98

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

99

GROSS N TRANSFORMATION RATES AND MICROBIAL POPULATION DYNAMICS UNDER FIELD AND LABORATORY CONDITIONS FROM TWO DIFFERENT ECOSYSTEMS  

EPA Science Inventory

Change of soil and environmental conditions can influence microbial activities and subsequent soil nitrogen (N) transformation processes. The objective of this study was to compare gross N transformation rates between field and laboratory incubation conditions using an old-field...

100

Laboratory Experiments and Investigations on the Reaction Rates of Mg-sulfates Under Mars Relevant Conditions  

NASA Astrophysics Data System (ADS)

Large deposits of hydrous Mg-sulfates was identified on Mars by orbital remote sensing (OMEGA on Mars Express and CRISM on Mars Reconnaissance Orbiter). Kieserite (MgSO4.H2O) and a non-specific polyhydrated sulfates are among the most observed and widely distributed sulfates (Bibring et al., 2005, Murchie et al., 2007). They frequently co-exist (Gendrin et al., 2005) and sometimes occur in alternative stratigraphic layers (Roach et al., 2008). Mg-sulfates were suggested, by compositional correlations and mineral models, to exist in Meridiani outcrops (Clark et al., 2005) and in rocks and regolith at Gusev (Squyres et al., 2006, Haskin et al., 2005, Wang et al., 2006, 2008); but no information on the hydration state of these sulfates can be extracted. We have conducted 188 experiments to investigate the stability fields and phase transition pathways of hydrous Mg-sulfates (Wang et al., 2009). In addition, we can extract the information on the reaction rates of five important dehydration and rehydration processes involved in these experiments. Our experiments were done at four temperatures (50C, 21C, 5C, and -10C) and ten relative humidity levels, with five hydrous Mg-sulfate species as starting phases. The rate information was extracted from the mineral identifications of the intermediate reaction products, measured by non-invasive Raman spectroscopy at regular time intervals during the entire duration of experiments (tens thousands hours). The rates for five processes are all strongly controlled by temperatures. We found that the experimental results match Arrhenius equation very well, thus the rate constants for dehydration and rehydration processes of Mg-sulfates at lower temperatures (down to 180K) can be approximately estimated by using the experimentally derived pre-exponential factor(s) and activation energy(s). In this study, only the orders of magnitudes for reaction rate ratios at different temperatures were considered. The estimated reaction rate ratios at different temperatures for five important processes helped us to understand the stable, especially the metastable, Mg-sulfate species that could be seen at Mars surface in non-polar regions during a moderate obliquity period. Therefore in addition to exam the spectral similarity, we now can use the knowledge gained through the laboratory experiments on stability field, phase transition pathway, and reaction rate of Mg-sulfates to evaluate the realistic mineral candidates for polyhydrated sulfates, that were so widely observed on Mars by OMEGA and CRISM. Furthermore, we will be able to investigate the formation mechanism of alternative stratigraphic layers of sulfates on Mars and the paleo-climatic conditions that they may imply.

Wang, A.; Freeman, J. J.

2009-12-01

101

Neural Tube Defects in Curly-Tail Mice. I. Incidence, Expression and Similarity to the Human Condition  

Microsoft Academic Search

The incidence of neurovertebral defects in mutant mice of the curly-tail strain was investigated and found to be similar to that observed in the same mice twenty-five years ago. The results of breeding experiments support the hypothesis of Gruneberg that the defects in these mice are probably caused by a recessive gene, the expression of which is markedly affected by

Susan Embury; Mary J. Seller; M. Adinolfi; P. E. Polani

1979-01-01

102

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

NASA Astrophysics Data System (ADS)

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 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. Laboratory measurements completed under this grant (NAGW-533), have shown that the opacity from, SO2 under simulated Venus conditions is best described by a different lineshape than was previously used in theoretical predictions. 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.

1997-03-01

103

Laboratory Studies of the Effects of Ambient Conditions, Soot Emissions, and Fuel Properties on Contrail Formation  

NASA Astrophysics Data System (ADS)

Contrail formation by aircraft can affect the global radiation budget and is the most uncertain component of aviation impacts on climate change. Field campaigns studying contrail formation have given insight into their formation pathways. However in order to improve simulations of contrail production, laboratory studies of the initial processes of contrail formation from aircraft-emitted soot are needed. As part of the Aviation Climate Change Research Initiative (ACCRI), laboratory studies of contrail formation from simulated aircraft emissions were performed at the particulate aerosol laboratory (PAL) at the NASA Glenn Research Center. The facility consists of a controlled soot source connected to a flow-through chamber which can simulate atmospheric conditions at altitudes up to 45,000 ft. Soot was made by a propane-fueled CAST generator and allowed to mix with water vapor and sulfuric acid to simulate aircraft emissions. Optical particle counters were employed at two distances from the nozzle tip that provided number concentration and size distributions of newly formed ice particles. The formation of ice particles is presented for chamber temperatures and pressures simulating altitudes between 15,000 and 40,000 feet. Initial results show the role of soot concentration, soot size, concentration of co-emitted pollutants and ambient conditions in ice particle formation.

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

2010-12-01

104

A comparative analysis of Painlev\\\\'e, Lax Pair, and Similarity Transformation methods in obtaining the integrability conditions of nonlinear Schr\\\\  

Microsoft Academic Search

We derive the integrability conditions of nonautonomous nonlinear Schr$\\\\rm\\\\ddot o$dinger equations using the Lax Pair and Similarity Transformation methods. We present a comparative analysis of these integrability conditions with those of the Painlev$\\\\rm\\\\acute{e}$ method. We show that while the Painlev$\\\\rm\\\\acute{e}$ integrability conditions restrict the dispersion, nonlinearity, and dissipation\\/gain coefficients to be space-independent and the external potential to be only a

U. Al Khawaja

2010-01-01

105

Unification and extension of the similarity scaling criteria and mixing transition for studying astrophysics using high energy density laboratory experiments or numerial simulations  

SciTech Connect

The Euler similarity criteria for laboratory experiments and time-dependent mixing transition are important concepts introduced recently for application to prediction and analysis of astrophysical phenomena. However Euler scaling by itself provides no information on the distinctive spectral range of high Reynolds number turbulent flows found in astrophysics situations. On the other hand, time-dependent mixing transition gives no indication on whether a flow that just passed the mixing transition is sufficient to capture all of the significant dynamics of the complete astrophysical spectral range. In this paper, a new approach, based on additional insight gained from review of Navier-Stokes turbulence theory, is developed. It allows for revelations about the distinctive spectral scale dynamics associated with high Reynolds number astrophysical flows. From this perspective, we caution that the energy containing range of the turbulent flow measured in a laboratory setting must not be unintentionally contaminated in such a way that the interactive influences of this spectral scale range in the corresponding astrophysical situation cannot be faithfully represented. In this paper we introduce the concept of a minimum state as the lowest Reynolds number turbulent flow that a time-dependent mixing transition must achieve to fulfill this objective. Later in the paper we show that the Reynolds number of the minimum state may be determined as 1.6 x 10{sup 5}. Our efforts here can be viewed as a unification and extension of the concepts of both similarity scaling and transient mixing transition concepts. At the last the implications of our approach in planning future intensive laser experiments or massively parallel numerical simulations are discussed. A systematic procedure is outlined so that as the capabilities of the laser interaction experiments and supporting results from detailed numerical simulations performed in recently advanced supercomputing facilities increase progressively, a strategy can be devised so that more and more spectral range dynamic structures and their statistical influences on evolving astrophysical flows can be progressively extended in laboratory investigations.

Zhou, Y

2006-08-21

106

Imagined and actual arm movements have similar durations when performed under different conditions of direction and mass  

Microsoft Academic Search

Several experiments have suggested that similar physiological substrates are involved in movement execution and motor imagery,\\u000a and that the same laws of movement control apply to both processes. Using a mental chronometry paradigm, we examined the effects\\u000a of movement direction and added mass on the duration of actual and imagined movements. Six subjects executed or imagined arm\\u000a movements in the

Charalambos Papaxanthis; Marco Schieppati; Rodolphe Gentili; Thierry Pozzo

2002-01-01

107

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

108

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 271C, >80 % RH and darkness. The complete life cycle, including pre-attachment periods for each parasitic stage, ranged from 126 to 228days. The pre-attachment, feeding and molting periods increased as the life cycle progressed from larva to adult female. Oviposition lasted about 20days, with the peak occurring on days 4 and 5. Longevity of nymphs and adult females was quite similar (approximately 250 and 240days, 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, Joo Luiz Horacio; Pires, Marcus Sandes; da Silva, Hlio Ricardo; Barros-Battesti, Darci Moraes

2012-10-26

109

Scaling methane oxidation: from laboratory incubation experiments to landfill cover field conditions.  

PubMed

Evaluating field-scale methane oxidation in landfill cover soils using numerical models is gaining interest in the solid waste industry as research has made it clear that methane oxidation in the field is a complex function of climatic conditions, soil type, cover design, and incoming flux of landfill gas from the waste mass. Numerical models can account for these parameters as they change with time and space under field conditions. In this study, we developed temperature, and water content correction factors for methane oxidation parameters. We also introduced a possible correction to account for the different soil structure under field conditions. These parameters were defined in laboratory incubation experiments performed on homogenized soil specimens and were used to predict the actual methane oxidation rates to be expected under field conditions. Water content and temperature corrections factors were obtained for the methane oxidation rate parameter to be used when modeling methane oxidation in the field. To predict in situ measured rates of methane with the model it was necessary to set the half saturation constant of methane and oxygen, K(m), to 5%, approximately five times larger than laboratory measured values. We hypothesize that this discrepancy reflects differences in soil structure between homogenized soil conditions in the lab and actual aggregated soil structure in the field. When all of these correction factors were re-introduced into the oxidation module of our model, it was able to reproduce surface emissions (as measured by static flux chambers) and percent oxidation (as measured by stable isotope techniques) within the range measured in the field. PMID:21196106

Abichou, Tarek; Mahieu, Koenraad; Chanton, Jeff; Romdhane, Mehrez; Mansouri, Imane

2010-12-31

110

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

111

The discovery of the principles of reinforcement, extinction, generalization, and differentiation of conditional reflexes in Pavlovs laboratories  

Microsoft Academic Search

The discovery of reinforcement, extinction, generalization, and differentiation with the conditional reflex method in Pavlovs\\u000a laboratories is described. Modern American introductory texts show that contemporary understanding of the experimental work\\u000a on conditioning in Pavlovs laboratories is derived from a 1927 English translation of Pavlovs lectures on the conditional\\u000a reflexes. The lectures present the discoveries topically, not chronologically. In contrast, this

George Windholz

1989-01-01

112

Laboratory emissivity measurements of the plagioclase solid solution series under varying environmental conditions  

NASA Astrophysics Data System (ADS)

New laboratory thermal infrared emissivity measurements of the plagioclase solid solution series over the 1700 400 cm-1 (6-25 ?m) spectral range are presented. Thermal infrared (TIR) spectral changes for fine-particulate samples (0-25 ?m) are characterized for the first time under different laboratory environmental conditions: ambient (terrestrial-like), half-vacuum (Mars-like), vacuum, and vacuum with cooled chamber (lunar-like). Under all environmental conditions the Christiansen Feature (CF) is observed to vary in a systematic way with Na-rich end-member (albite) having a CF position at the highest wave number (shortest wavelength) and the Ca-rich end-member (anorthite) having a CF position with the lowest wave number (longest wavelength). As pressure decreases to <10-3 mbar four observations are made: (1) the CF position shifts to higher wave numbers, (2) the spectral contrast of the CF increases relative to the RB, (3) the spectral contrast of the RB in the 1200-900 spectral range decreases while the spectral contrast of the RB in the 800-400 spectral range either increases or remains the same and (4) the TF disappears. A relationship between the wavelength position of the CF measured under simulated lunar conditions and plagioclase composition (An#) is developed. Although its exact form may evolve with additional data, this linear relationship should be applied to current and future TIR data sets of the Moon. Our new spectral measurements demonstrate how sensitive thermal infrared emissivity spectra of plagioclase feldspars are to the environmental conditions under which they are measured and provide important constraints for interpreting current and future thermal infrared data sets.

Donaldson Hanna, K. L.; Thomas, I. R.; Bowles, N. E.; Greenhagen, B. T.; Pieters, C. M.; Mustard, J. F.; Jackson, C. R. M.; Wyatt, M. B.

2012-11-01

113

New Laboratory Measurements of the Centimeter-Wavelength Properties of Ammonia Under Deep Jovian Atmospheric Conditions  

NASA Astrophysics Data System (ADS)

Over 800 measurements of the opacity of ammonia have been made in the 5-20 cm wavelength range at pressures ranging from 0.05-96 bars, temperatures from 330-450K, and mixing ratios from 0.05-100% in a hydrogen-helium atmosphere using an ultra-high pressure system. An ammonia absorptivity model that is accurate under very high pressure conditions is necessary for the Juno microwave radiometer (MWR) to successfully retrieve the deep abundance profile of Jupiter. Current and future measurements of the opacity of ammonia under simulated deep jovian conditions, and an estimation of compressibility of ammonia under the same conditions will be used to create a new model that more accurately characterizes the centimeter-wavelength properties of ammonia in support of the Juno MWR. Furthermore, at least one laboratory measurement study indicates that water vapor can efficiently broaden the 572 GHz rotational transition of ammonia (Belov et al., 1983), and this could be true for the inversion transitions of ammonia as well. Future work will involve laboratory measurements of the opacity of mixtures of ammonia and water vapor under simulated jovian conditions using the ultra-high pressure system. These measurements will directly improve our understanding of centimeter-wavelength absorption by ammonia in the jovian planets, and improve retrievals from the Juno MWR at Jupiter. This work was supported by NASA Contract NNM06AA75C from the Marshall Space Flight Center supporting the Juno Mission Science Team, under Subcontract 699054X from the South-west Research Institute

Devaraj, Kiruthika; Steffes, P. G.

2010-10-01

114

Survival, food consumption and growth of Norway lobster (Nephrops norvegicus) kept in laboratory conditions.  

PubMed

Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals. The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L., 1758) under laboratory conditions. The aim of the present study was to examine food consumption, growth and physiology of the Norway lobster N. norvegicus under laboratory conditions. N. norvegicus (15 g wet weight) were distributed into 1001 tanks consisting of five numbered compartments each. They were fed the experimental diets (frozen mussels and pellets) for a period of 6 months. A group of starved Nephrops was stocked and fasted for 8 months. Although Nephrops grew well when fed the frozen mussels diet, feeding on a dry pellet feed was unsatisfactory. The starvation group, despite the fact that showed the highest mortality (50%), exhibited a remarkable tolerance to the lack of food supply. The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets. The deviations from the mussel's diet for asparagine, alanine and glutamic acid suggest a deficiency of these amino acids in this diet. The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids, except for arginine, proline and glycine. The present study contributes to the improvement of our knowledge on nutritional requirements of the above species. PMID:21392343

Mente, Elena

2010-09-01

115

Feeding and breeding aspects of Stomoxys calcitrans (Diptera: Muscidae) under laboratory conditions.  

PubMed

Bionomic aspects of Stomoxys calcitrans (Linnaeus, 1758) (Diptera: Muscidae) were studied under laboratory conditions. For this reason, laboratory-rearing techniques were optimized at the National Veterinary School of Toulouse. The colony was maintained at 252C, 5010% RH under a 12-hour light cycle and observed daily. The size of each adult cage is 30x30x30 cm and designed to house about 500-1,000 flies. The average cycle from egg to adult was 19.21.7 days. The mean longevity of imagos was 9.35.8 days and not significantly different between sexes. Stable flies were split into two groups; the first was fed with blood, honey and water, and the second was fed only with honey and water. The mean weight of a blood meal was 11.13.8 mg with no significant differences between males and females. The mean longevity of non-blood fed flies was found to be significantly higher (10.43.9 days) than those fed with blood. The maximum lifespan was shorter for non-blood fed males (17 days) and females (18 days) than for those fed with blood (females: 24 days, males: 23 days). Under these laboratory conditions, S. calcitrans rearing was successfully established. In the end, the number of expected generations of S. calcitrans and the net reproduction rate were estimated to be 11.8 generations/year and 16.2 living females per female respectively. PMID:23193515

Salem, A; Franc, M; Jacquiet, P; Bouhsira, E; Linard, E

2012-11-01

116

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

117

The Life Cycle of the Root Borer, Oryctes agamemnon, Under Laboratory Conditions  

PubMed Central

The root borer, Oryctes agamemnon Burmeister (Coleoptera: Scarabaeidae), has become a serious pest of date palm trees in southwest Tunisia. Under natural conditions, mated females lay eggs in different parts of palm tree: between the hairy roots, all along the stem at the leaf axils and at the base of cut branches. Larvae bore into targeted places of the plant and were never seen outside. Pupation takes place in the plant and emergence of the adults begins in June. Larval feeding causes extensive damage to the respiratory roots. To examine the life cycle more closely, the O. agamemnon life cycle was studied under laboratory conditions. Different larval stages were collected from infested oases in Tozeur and placed in plastic boxes with natural food that was collected from the oases. After emergence, adults were paired in opaque plastic boxes for mating with the same food substrate which also served as an oviposition site. Eggs were collected daily and isolated in new boxes. Hatched eggs were recorded. The number of larval instars was determined by measuring the width of cephalic capsules. Under laboratory conditions (23 2'C and 55 6% RH)embryogenesis took 14.3 1.42 days and the first, second and third larval instars were 33.1 2.69, 63.88 6.6 and 118.3 13.38 days respectively. The pupal period lasted 24.1 3.02 days and the adult 65.27 9.48 days. These facts indicated that O. agamemnon is univoltine.

Soltani, Rasmi; Chaieb, Ikbel; Hamouda, Med Habib Ben

2008-01-01

118

Self-similar bumps and wiggles: Isolating the evolution of the BAO peak with power-law initial conditions  

NASA Astrophysics Data System (ADS)

Motivated by cosmological surveys that demand accurate theoretical modeling of the baryon acoustic oscillation (BAO) feature in galaxy clustering, we analyze N-body simulations in which a BAO-like Gaussian bump modulates the linear theory correlation function ?L(r)=(r0/r)n+3 of an underlying self-similar model with initial power spectrum P(k)=Akn. These simulations test physical and analytic descriptions of BAO evolution far beyond the range of most studies, since we consider a range of underlying power spectra (n=-0.5, -1, -1.5) and evolve simulations to large effective correlation amplitudes (equivalent to ?8=4-12 for rbao=100h-1Mpc). In all cases, nonlinear evolution flattens and broadens the BAO bump in ?(r) while approximately preserving its area. This evolution resembles a diffusion process in which the bump width ?bao is the quadrature sum of the linear theory width and a length proportional to the rms relative displacement ?pair(rbao) of particle pairs separated by rbao. For n=-0.5 and n=-1, we find no detectable shift of the location of the BAO peak, but the peak in the n=-1.5 model shifts steadily to smaller scales, following rpeak/rbao=1-1.08(r0/rbao)1.5. The perturbation theory scheme of McDonald (2007) [P. McDonald, Phys. Rev. DPRVDAQ1550-7998 75, 043514 (2007).10.1103/PhysRevD.75.043514] and, to a lesser extent, standard 1-loop perturbation theory are fairly successful at explaining the nonlinear evolution of the Fourier power spectrum of our models. Analytic models also explain why the ?(r) peak shifts much more for n=-1.5 than for n?-1, though no ab initio model we have examined reproduces all of our numerical results. Simulations with Lbox=10rbao and Lbox=20rbao yield consistent results for ?(r) at the BAO scale, provided one corrects for the integral constraint imposed by the uniform density box.

Orban, Chris; Weinberg, David H.

2011-09-01

119

Influence of experimental conditions on nitrogenous excretion by Lake Michigan Mysis relicta (Lovn): laboratory studies with animals acclimated in Fragilaria  

Microsoft Academic Search

In laboratory experiments, rates of excretion of ammonia and urea by Lake MichiganMysis relicta were compared for animals incubated in the presence and the absence of algal food (Fragilaria crotonensis chemostat outflow). Prior to experiments, all animals were acclimated to laboratory conditions and the experimental food for 24 weeks. Algae used in experiments were enriched in the dark with nutrients

D. B. Seale; M. E. Boraas

1982-01-01

120

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

121

Testing shields in the Argonne National Laboratory fuel conditioning facility support areas.  

PubMed

Testing has been completed for two lightly shielded areas that support operations in the Fuel Conditioning Facility at the Argonne National Laboratory site at the Idaho National Engineering Laboratory. Operational requirements dictated the use of a radiography source containing 0.44 TBq (12 Ci) of 192Ir to challenge reinforced concrete and steel shields that surround a decontamination, maintenance, and repair area for contaminated equipment used in hot cell operations. A more intense source containing 0.89 TBq (24 Ci) of 192Ir was used to test lead shot and steel shields around tanks in a radioactive liquid waste system and the boundaries of the room that contained it. Measurement procedures were developed to find design flaws and construction deficiencies while minimizing radiation exposure to test participants. While the shields are adequate to limit gamma ray deep dose equivalents to 10 mSv y(-1) (1 rem y(-1)) or less to facility personnel, several modifications were necessary to assure that the attenuation is adequate to keep dose rates less than 5 microSv h(-1) (0.5 mrem h(-1)) in normally occupied areas. PMID:8972837

Courtney, J C; Klann, R T

1997-01-01

122

Comparison of the emission of IR decoy flare under controlled laboratory and on-field conditions  

NASA Astrophysics Data System (ADS)

The knowledge of the optical properties of decoy flares such as peak intensity, rise time and function time as well as the trajectory after being ejected are crucial to ensure the decoy effectiveness and the protection of the aircraft. The Countermeasures Laboratory of the "Institute of technology Maraosa" (ITM) has performed a measurement campaign during the spring of 2008 to determine the IR decoy signature in both wind tunnel test and in-flight conditions. Both tests are complementary because of the different test conditions that influence the behavior of the flare burn profile. Deviations were found between two sets of data due to high wind-stream and high altitudes. Comparison of both sets of results allows extrapolating the measurements in stationary conditions to that of a real scenario. Besides, these comparisons are useful to validate IR flare emission simulation software. The radiant intensity and burn time was calculated trough a sequence of calibrated images. The effect of the influent parameter on the emitted intensity were also Identified and measured. Analysis of in-flight measurements took into account the altitude, aerodynamic conditions, angle aspect and of course the wind speed. Sky radiance and atmospheric transmittance were also calculated. The radiation measurements of IR flares on flight and wind tunnel test are performed with a MWIR camera equipped with a 350mm focal length lens. Besides the camera a Circular Variable Filter (CVF) spectrorradiometer was used for the tunnel test. For the field trial an automatic tracking system of targets were used in order to determine the flare trajectory.

Snchez Oliveros, Carmen; Martn Aragn, Laura; Macias Jareo, Raquel

2009-09-01

123

Comparison of three models of actigraph accelerometers during free living and controlled laboratory conditions.  

PubMed

The aim of this study was to compare the outputs of three commonly used uniaxial Actigraph models (Actitrainer, 7164 and GT1M) under both free-living and controlled laboratory conditions. Ten adults (mean age = 24.71.1 years) wore the three Actigraph models simultaneously during one of day free-living and during a progressive exercise protocol on a treadmill at speeds between 1.5 and 5.5 miles per hour (mph). During free-living the three Actigraph models produced comparable outputs in moderate, vigorous and moderate-to-vigorous physical activity (MVPA) with effect sizes typically <0.2, but lower comparability was seen in sedentary and light categories, as well as in total step counts (effect sizes often >0.30). In controlled conditions, acceptable comparability between the three models was seen at all treadmill speeds, the exception being walking at 1.5 mph (mean effect size = 0.48). It is concluded that care should be taken if different Actigraph models are to be used to measure and compare light physical activity, step counts and walking at very low speeds. However, using any of these three different Actigraph models to measure and compare levels of MVPA in free-living adults seems appropriate. PMID:23679150

Lee, Ka-Yiu; Macfarlane, Duncan J; Cerin, Ester

2012-03-08

124

The Life Cycle of the Antarctic Nematode Plectus murrayi Under Laboratory Conditions  

PubMed Central

We study and describe the life cycle of Plectus murrayi, a free-living, bacterivorous soil nematode endemic to terrestrial Antarctica. The study was performed at 15C, a temperature identified as optimal for growth rate studies in the laboratory. Under these conditions, we observed that the first molt occurs in the egg, and second-stage juveniles hatch 12 to 14 d after egg laying. Individuals undergo three subsequent molts to become adults 23 to 26 d after hatching with a final average length of 950 ?m. Egg-laying begins 41 to 43 d after hatching, resulting in an egg-to-egg life cycle ranging from 53 to 57 d under our experimental conditions. Considering that the average soil temperature during austral summers in the McMurdo Dry Valleys is only a few degrees above freezing, it is highly likely that many, if not most of these animals, require more than 1 yr to complete their entire life cycle. Our study supports other research that establishes P. murrayi as an important model organism for studying adaptation to extreme environmental stress.

de Tomasel, Cecilia Milano; Adams, Byron J.; Tomasel, Fernando G.; Wall, Diana H.

2013-01-01

125

Intraspecific non-sexual interactions of Grammostola schulzei (Araneae: Theraphosidae) under laboratory conditions.  

PubMed

Intraspecific interactions of araneomorph spiders have received considerable attention, but there are few detailed studies on intraspecific interactions of mygalomorph spiders. Moreover, a thorough understanding of theraphosid biology and ecology is necessary from a conservation standpoint because natural populations may be threatened by habitat disturbances and captures for pet commerce. We described the behavior of conspecific individuals of Grammostola schulzei during non-sexual interactions, under laboratory conditions. Pairs of individuals involving adult males, adult females and juveniles were confronted and observed in resident and intruder conditions, totalizing 115 trials. When confronted two adult females, they retreated or grappled, and performed gaping display with bite attempts, usually resulted in severe injury of the intruder spiders. When confronted females with large juveniles, we frequently observed cannibalism on juveniles. Juveniles exposed to females or to other juveniles retreated or made leg tapping with forelegs and palpal drumming, which are common displays of courting adult males. Adult males courted and clasped some juveniles, but juveniles avoided or reject clasping. The behaviors observed during intraspecific interactions could play an important role determining spatial distribution and could lead to behavioral adaptations of territoriality. PMID:22017123

Ferretti, Nelson E; Prez-Miles, Fernando

2011-09-01

126

Remelting of highly cross-linked polyethylene worn under laboratory conditions.  

PubMed

It has been suggested that apparent wear damage in highly cross-linked polyethylene acetabular liners can be removed with subsequent remelting of retrieved liners. To test this hypothesis, we remelted liners that had been previously tested under controlled laboratory conditions and that had experienced nonzero wear rates and visible wear damage. Five liner groups were examined: three with a range of irradiation doses without heat treatment, and two irradiated to 100 kGys, one with remelting, and the other annealing. All groups had been worn in a hip simulator under impingement conditions that produced nonzero wear rates and loss of machining marks. Each liner was cut into quadrants that were graded for wear damage before and after posttest remelting. Cross-linked liners not previously heat-treated lost all prior damage and all machining marks. Remelted liners and three of six annealed liners experienced only a slight return of machining marks at the interface of the burnished area and the remaining intact machining marks. Our experiments represent a severe wear case but demonstrate removal of material from the surface through measurable wear prevents the return of identifiable machining marks despite remelting. PMID:18090470

Lazzarini, Adam M; Cottrell, Jocelyn M; Padgett, Douglas E; Wright, Timothy M

2007-12-01

127

The Life Cycle of the Antarctic Nematode Plectus murrayi Under Laboratory Conditions.  

PubMed

We study and describe the life cycle of Plectus murrayi, a free-living, bacterivorous soil nematode endemic to terrestrial Antarctica. The study was performed at 15C, a temperature identified as optimal for growth rate studies in the laboratory. Under these conditions, we observed that the first molt occurs in the egg, and second-stage juveniles hatch 12 to 14 d after egg laying. Individuals undergo three subsequent molts to become adults 23 to 26 d after hatching with a final average length of 950 ?m. Egg-laying begins 41 to 43 d after hatching, resulting in an egg-to-egg life cycle ranging from 53 to 57 d under our experimental conditions. Considering that the average soil temperature during austral summers in the McMurdo Dry Valleys is only a few degrees above freezing, it is highly likely that many, if not most of these animals, require more than 1 yr to complete their entire life cycle. Our study supports other research that establishes P. murrayi as an important model organism for studying adaptation to extreme environmental stress. PMID:23589658

de Tomasel, Cecilia Milano; Adams, Byron J; Tomasel, Fernando G; Wall, Diana H

2013-03-01

128

Application of Similar Media Scaling and Conditional Simulation for Modeling Water Flow and Tritium Transport at the Las Cruces Trench Site  

NASA Astrophysics Data System (ADS)

Similar media scaling and geostatistical analyses are used to characterize the spatial variability of soil hydraulic properties at the Las Cruces Trench Site in New Mexico. A simple method is described for conditioning the hydraulic properties used for unsaturated water flow and solute transport modeling, based on the spatial distributions of initial field-measured water contents and a set of scale-mean hydraulic parameters determined from the scaling analysis. This method is used to estimate hydraulic properties for numerical simulations of the latest field-scale flow and transport experiment conducted at the Las Cruces Trench Site. Relatively good matches between the observed and simulated flow and transport behavior are obtained without model calibration. The results of this study suggest that using similar media scaling in conjunction with the described conditioning procedure can significantly reduce the uncertainty in predictions of water flow and solute transport in spatially variable soils.

Rockhold, Mark L.; Rossi, Richard E.; Hills, Richard G.

1996-03-01

129

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

130

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

131

Laboratory Investigations of a Low-Swirl Injector with H2 and CH4 at Gas Turbine Conditions  

SciTech Connect

Laboratory experiments were conducted at gas turbine and atmospheric conditions (0.101 < P{sub 0} < 0.810 MPa, 298 < T{sub 0} < 580K, 18 < U{sub 0} < 60 m/s) to characterize the overall behaviors and emissions of the turbulent premixed flames produced by a low-swirl injector (LSI) for gas turbines. The objective was to investigate the effects of hydrogen on the combustion processes for the adaptation to gas turbines in an IGCC power plant. The experiments at high pressures and temperatures showed that the LSI can operate with 100% H{sub 2} at up to {phi} = 0.5 and has a slightly higher flashback tolerance than an idealized high-swirl design. With increasing H{sub 2} fuel concentration, the lifted LSI flame begins to shift closer to the exit and eventually attaches to the nozzle rim and assumes a different shape at 100% H{sub 2}. The STP experiments show the same phenomena. The analysis of velocity data from PIV shows that the stabilization mechanism of the LSI remains unchanged up to 60% H{sub 2}. The change in the flame position with increasing H{sub 2} concentration is attributed to the increase in the turbulent flame speed. The NO{sub x} emissions show a log linear dependency on the adiabatic flame temperature and the concentrations are similar to those obtained previously in a LSI prototype developed for natural gas. These results show that the LSI exhibits the same overall behaviors at STP and at gas turbine conditions. Such insight will be useful for scaling the LSI to operate at IGCC conditions.

Cheng, R. K.; Littlejohn, D.; Strakey, P.A.; Sidwell, T.

2008-03-05

132

42 CFR 493.1421 - Condition: Laboratories performing moderate complexity testing; testing personnel.  

Code of Federal Regulations, 2012 CFR

...Laboratories performing moderate complexity testing; testing personnel. 493.1421 Section...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...

2012-10-01

133

42 CFR 493.1487 - Condition: Laboratories performing high complexity testing; testing personnel.  

Code of Federal Regulations, 2012 CFR

...Laboratories performing high complexity testing; testing personnel. 493.1487 Section...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...

2012-10-01

134

42 CFR 493.807 - Condition: Reinstatement of laboratories performing nonwaived testing.  

Code of Federal Regulations, 2012 CFR

...laboratories performing nonwaived testing. 493.807 Section 493...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...Participation in Proficiency Testing for Laboratories Performing Nonwaived Testing § 493.807...

2012-10-01

135

42 CFR 493.1421 - Condition: Laboratories performing moderate complexity testing; testing personnel.  

Code of Federal Regulations, 2011 CFR

...Laboratories performing moderate complexity testing; testing personnel. 493.1421 Section...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...

2011-10-01

136

42 CFR 493.1487 - Condition: Laboratories performing high complexity testing; testing personnel.  

Code of Federal Regulations, 2011 CFR

...Laboratories performing high complexity testing; testing personnel. 493.1487 Section...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...

2011-10-01

137

Laboratory measurements of basalts electrical resistivity under deep oceanic crustal conditions  

NASA Astrophysics Data System (ADS)

For sixty years, electrical resistivity soundings have been used to explore geothermal resources in Iceland. They have generally revealed two zones of high electrical conductivity, one at shallow depths (Flovenz et al., 1985) and another at 10-30 km depth (Beblo and Bjrnsson, 1978). The interpretation of these conductive zones in terms of composition and in-situ physical conditions is often ambiguous, as various parameters can explain these observations like temperature, partial melting, change in minerals and type of pore fluid. Accurate interpretations of resistivity data needed for geothermal exploration require laboratory measurements of electrical conductivities performed on rock samples at different conditions. We present here a method to measure electrical conductivity of rocks under deep crustal conditions for oceanic crustal rock, i.e. at temperatures up to 600C, confining pressures up to 200 MPa and pore fluid pressures up to 50 MPa. The method has been developed in a internally heated, gas pressure apparatus (Paterson press). Electrical conductivity is measured on large cylindrical samples (15 to 22 mm in diameter and 10 to 15 mm in length) in a two parallel electrodes geometry. Such experiments require that the fluid saturated sample is sleeved in an impermeable and deformable jacket serving to separate the confining pressure medium (high pressure argon) from the pore fluid saturated sample. At temperature above 200C a metal sleeve must be used, although it induces high leakage currents that could affect electrical measurements. The leakage currents are reduced using addition of 2 guard-ring parallel electrodes (Glover, 1995). The electrical impedance of basalt has been measured over a frequency range from 10 -1 to 106 Hertz. Five different types of low porosity basalts were selected to cover a range in alteration grade, from albitic to granulite facies. Application of this method will provide data on electrical conductivity of fresh and altered saturated basalts at in-situ conditions. These data will facilitate the understanding of both transient electromagnetic and with magnetotelluric data together with logging data from oceanic crust. Beblo, M. and Bjrnsson, A. Magnetotelluric investigation of the lower crust and upper mantle beneath Iceland. Journal of Geophysics, 45, 1-16. 1978 Flovenz O.G., Georgsson L. S. and Arnason, Knutur. Resistivity Structure of the Upper Crust in Iceland. Journal of geophysical research, Vol.90 NO B12, Pages 10,136-10 150. 1985. Glover Paul W.J., Vine F.J.. Beyong KTB- Electrical Conductivity of the Deep Continental crust. Survey in Geophysics. Vol. 16, pages 47-62. 1995.

Violay, M. E.; Gibert, B.; Azais, P.; Pezard, P. A.; Flovenz, O. G.; Asmundsson, R.

2009-12-01

138

[The effect of chromium removal by algae-bacteria Bostrychia calliptera (Rhodomelaceae) consortia under laboratory conditions].  

PubMed

Water pollution is one of the most important environmental problems worldwide. Recently, biotechnology studies have oriented efforts to study algae-bacterium consortia with the aim to understand the mechanisms to find a possible solution in environmental sciences. This study determined the percentage of chromium removal by the alga-bacterium association exposed to a set of different chromium concentrations under controlled in vitro conditions. Wild plants of Bostrychia calliptera associated with bacterial populations were collected from Dagua River, Pacific coast of Colombia, and were monitored in the laboratory. The trial was conducted with synthetic seawater in bioreactors at two chromium levels: 5 and 10mg/L, and four different experimental treatments: i) algae-bacteria (AB), ii) algae with antibiotic (AA), iii) algal surface sediment, Natural Bacterial Consortium (CBN), and iv) the control without algae or bacteria. The experimental design followed a model of two factors (chromium concentration x combination types) with repeated measures using one factor. The microbial population behavior and the chromium concentration percentage were monitored by using atomic absorption spectroscopy (AAS). According to the data, Algae-bacteria (AB) treatment was the most efficient combination at 10mg/L (87%), whereas the bacterial consortia (CBN) was the most efficient at 5mg/L (62.85%). The results showed significant differences of chromium uptake between algae-bacteria (AB) and natural bacterial consortia (CBN), meaning the importance of those treatments in the chromium removal from coastal waters. PMID:23025079

Rengifo-Gallego, Ana Luca; Pea-Salamanca, Enrique; Benitez-Campo, Neyla

2012-09-01

139

Photodegradation of organic pollutants on the spruce needle wax surface under laboratory conditions.  

PubMed

The photochemistry of selected organic compounds, including common pollutants, on the paraffin (as a model matrix) and spruce wax surfaces was studied under laboratory conditions. Two model transformations were evaluated: (1) intramolecular rearrangements of valerophenone and 2-nitrobenzaldehyde, and (2) hydrogen abstraction between an excited benzophenone and the hydrocarbon paraffin/wax chains. The steric or polar influence of the solid matrix on conformational and translational motion, its optical properties, hydrogen abstraction probabilities, and consequences of the guest-molecule segregation are discussed in this work. Furthermore, the photochemical reactivity of some common anthropogenic pollutants, such as chlorinated biphenyls (4-chlorobiphenyl, 2,4-dichlorobiphenyl, and 4,4'-dichlorobiphenyl), 4-chlorophenol, and DDT, was evaluated. The surface of spruce wax is presented as probable reaction medium for photochemical transformations. Although the matrix presents certain restrictions for bimolecular reactions, common photodegradations should be generally feasible in nature. In addition, paraffin was found to be a suitable model matrix for the studies of possible photochemical transformations that can occur on natural plant surfaces. PMID:15519385

Dolinov, Jindriska; Klnov, Jana; Kln, Petr; Holoubek, Ivan

2004-12-01

140

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

2008-02-20

141

Laboratory Study of Water Ice Growth Rates at Martian Atmosphere Conditions  

NASA Astrophysics Data System (ADS)

The formation and growth of water ice clouds play a pivotal role in the martian hydrological cycle, and any robust model of the climate of Mars must account for the effects of these processes. Unfortunately, the growth behavior of water ice at temperatures and pressures relevant to martian studies is not well characterized, requiring modelers to rely on extrapolations from data sets typically taken from terrestrial literature. The present laboratory study charts the growth rate of water ice as a function of temperature (approximately -120 to -80C) and pressure (approximately 1E-7 to 1E-4 Torr), principally in the phase space between nucleation and the vapor/solid equilibrium line. The appearance and subsequent growth of ice on a silicon wafer were monitored via infrared spectroscopy, and the time derivative of the characteristic water ice absorbance band was used to calculate net rates of deposition and sublimation as pressure and temperature were varied around equilibrium. These data were further interpreted to yield values for the net sticking coefficient of vapor phase molecules to the ice surface. These results will be beneficial to modelers of the martian climate, as they provide further insight into how quickly martian water ice clouds should be expected to form and dissipate under a given set of conditions.

Mar, B. D.; Phebus, B. D.; Colaprete, A.; Stone, B. M.; Iraci, L. T.

2009-12-01

142

Effect of two herbicides on Xenylla welchi (Hexapoda:Collembola) under laboratory conditions.  

PubMed

Xenylla welchi was used to evaluate toxicity of two herbicide formulations, pretilachlor (50 EC) and pendimethalin (30 EC) under laboratory conditions. Twenty four hours LC?? value of pretilachlor and pendimethalin formulations on Xenylla welchi were 72.7 and 190.0 g a.i/ha respectively which were less than their corresponding recommended agricultural doses. Again pretilachlor attained fastest LT?? (110 min) followed by pendimethalin (140 min). Significant reductions in hatching success were noted with the application of both the herbicide formulations at all doses excepting /? and /??th of LC?? (9.1, 7.3 and 23.8, 19.0 g a.i/ha for pretilachlor and pendimethalin, respectively). Hatching success of the test specimens recorded 44.1 and 63.3% reduction from control for the highest applied dose ( of LC??) of pretilachlor and pendimethalin, respectively. Juveniles of Xenylla welchi exposed to /?, /? and /??th LC?? for pretilachlor (12.1, 9.1, 7.3 g a.i/ha) and /? and /??th LC?? for pendimethalin (23.8, 19.0 g ai/ha) survived and exhibited increased moulting frequency (7 moultings in 28 days in both the herbicide treatments) in comparison to control (8 moulting in 42 days). Test specimens required 26.0 1.2 and 28.1 2.1 days to attain sexual maturity exposed to pretilachlor and pendamethalin respectively which was significantly less than control (42 2.6 days). PMID:21523507

Haque, A; Das Gupta, R; Chakravorty, P P

2011-04-27

143

Repellency of aromatic turmeric Curcuma aromatica under laboratory and field conditions.  

PubMed

Three Curcuma species, Curcuma aeruginosa (pink and blue ginger), Cu. aromatica (aromatic turmeric), and Cu. xanthorrhiza (giant curcuma), were selected for investigation of mosquito repellent activity. In a laboratory study, a 95% ethanol extract of each plant was tested for repellent activity of Aedes togoi on human volunteers. Only Cu. aromatica extract showed repellency against Ae. togoi with ED50 and ED95 values of 0.061 and 1.55 mg/cm2, respectively. It also provided biting protection for 3.5 h when applied at a concentration of 25 g%. The ethanolic extract of Cu. aromatica was therefore chosen for further repellent activity under field conditions, where it had a protective effect against Armigeres subalbatus, Culex quinquefasciatus, and Cx. tritaeniorhynchus. The ethanol-extracted Cu. aromatica did not cause dermal irritation when applied to human skin. No adverse effects on human volunteers were observed 2 mo after application. Therefore, Cu. aromatica extract can be applied as an effective personal protection measure against mosquito bites. PMID:14714673

Pitasawat, Benjawan; Choochote, Wej; Tuetun, Benjawan; Tippawangkosol, Pongsri; Kanjanapothi, Duangta; Jitpakdi, Atchariya; Riyong, Duangrat

2003-12-01

144

Algal food selection and digestion by larvae of the pestiferous chironomid Chironomus Crassicaudatus under laboratory conditions.  

PubMed

Feeding preference of Chironomus crassicaudatus 4th instars when fed on 5 algal species, Anabaena flos-aquae, Botryococcus braunii, Lyngbia cf. aeruginosa, Microcystis sp., and Scenedesmus quadricauda was studied under laboratory conditions. The various algal species were mixed in pairs at 1:1 ratio (fresh weight) to create 10 possible test combinations. The larvae were allowed to feed individually for 8 h on each algal mixture in tissue culture plates having 4 replicates. Four identical algal mixtures were simultaneously used without larvae as controls. After feeding, larvae and excrement were removed, and remaining algae from feeding trials and controls were fixed with Lugol's solution; the final ratio of algal species in each mixture was determined microscopically. Feeding preferences of C. crassicaudatus early 4th instars, in descending order, was L. cf. aeruginosa, A. flos-aquae, B. braunii, Microcystis sp., and S. quadricaudata. To evaluate algal digestibility, larval excrement was collected and the proportion of live and dead cells was determined by microscopic observations with the use of visible and ultraviolet light (epifluorescence). Anabaena flos-aquae and L. cf. aeruginosa were the easiest to digest, followed by Microcystis sp. and S. quadricaudata, whereas no digestion of B. braunii was observed. Cultures of larval excrement revealed the presence of some viable cells of all 5 tested algal species. PMID:15669393

Frouz, Jan; Ali, Arshad; Lobinske, Richard J

2004-12-01

145

Dissipation kinetics of tetraconazole in three types of soil and water under laboratory condition.  

PubMed

Laboratory experiment was conducted to understand the persistence behavior of tetraconazole in three soils of West Bengal (alluvial, red lateritic, and coastal saline) and also in water maintained at three different pH (4.0, 7.0, and 9.2) conditions. Processed soil samples (100g) were spiked at two treatment doses: 2.5?g/g (T1) and 5.0?g/g (T2). Double distilled buffered water (200ml) was spiked at two treatment doses: 1.0?g/ml (T1) and 2.00?g/ml (T2). The tetraconazole dissipation followed first-order reaction kinetics and the residual half-life (T 1/2) values in soil were found to be in the range of 66.9-77.2days for T1 and 73.4-86.0days for T2. The persistence increased in the order red lateritic > new alluvial > coastal saline. Interestingly, the red lateritic soil exhibited the lowest pH (5.56) and organic carbon (0.52%) content as compared to other two soils. However, the dissipation of tetraconazole in case of water was not pH dependant. The T 1/2 values in water were in the range of 94 to 125days. The study indicated the persistent nature of tetraconazole in soil and water. PMID:23813125

Alam, Samsul; Sengupta, Dwaipayan; Kole, Ramen Kumar; Bhattacharyya, Anjan

2013-06-30

146

Assessment of metolachlor and diuron leaching in a tropical soil using undisturbed soil columns under laboratory conditions.  

PubMed

In the present study, diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea] and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-metoxi-1-methylethyl)acetamide] leaching was studied in undisturbed soil columns collected in a cotton crop area in Mato Grosso State, Brazil. The pesticides were applied to the soil surface in dosages similar to those used in a cotton plantation. To assess the leaching process, soil columns were submitted to simulated rain under laboratory conditions at 25 3C, in the absence of wind and direct solar radiation. During the rain simulations, leachate solutions were collected and herbicide concentrations were determined. At the end of the experiment, the soil columns were cut into 10 cm sections to determine the remaining herbicide concentrations through the soil profile. Metolachlor was detected in all soil sections, and approximately 4% of the applied mass was leached. Diuron was detected only in the upper two soil sections and was not detected in the leachate. A linear correlation (r > 0.94) between the metolachlor soil concentrations and the organic contents of the soil sections was observed. Mass balance suggests that around 56% of diuron and 40% of metolachlor were degraded during the experiments. Measurements of the water table depth in the area where the samples were collected showed that it varied from 2 to 6 m and is therefore vulnerable to contamination by the studied herbicides, particularly metolachlor, which demonstrated a higher leaching potential. PMID:23305279

Dores, Eliana F G C; De Souza, Luana; Villa, Ricardo D; Pinto, Alicio Alves

2013-01-01

147

Degradation of Cry1Ac protein within transgenic Bacillus thuringiensis rice tissues under field and laboratory conditions.  

PubMed

To clarify the environmental fate of the Cry1Ac protein from Bacillus thuringiensis subsp. kurstaki (Bt) contained in transgenic rice plant stubble after harvest, degradation was monitored under field conditions using an enzyme-linked immunosorbent assay. In stalks, Cry1Ac protein concentration decreased rapidly to 50% of the initial amount during the first month after harvest; subsequently, the degradation decreased gradually reaching 21.3% when the experiment was terminated after 7 mo. A similar degradation pattern of the Cry1Ac protein was observed in rice roots. However, when the temperature increased in April of the following spring, protein degradation resumed, and no protein could be detected by the end of the experiment. In addition, a laboratory experiment was conducted to study the persistence of Cry1Ac protein released from rice tissue in water and paddy soil. The protein released from leaves degraded rapidly in paddy soil under flooded conditions during the first 20 d and plateaued until the termination of this trial at 135 d, when 15.3% of the initial amount was still detectable. In water, the Cry1Ac protein degraded more slowly than in soil but never entered a relatively stable phase as in soil. The degradation rate of Cry1Ac protein was significantly faster in nonsterile water than in sterile water. These results indicate that the soil environment can increase the degradation of Bt protein contained in plant residues. Therefore, plowing a field immediately after harvest could be an effective method for decreasing the persistence of Bt protein in transgenic rice fields. PMID:18284753

Li, Yunhe; Wu, Kongming; Zhang, Yongjun; Yuan, Guohui

2007-10-01

148

42 CFR 493.1459 - Condition: Laboratories performing high complexity testing; general supervisor.  

Code of Federal Regulations, 2012 CFR

...performing high complexity testing; general supervisor. ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1459...

2012-10-01

149

42 CFR 493.1447 - Condition: Laboratories performing high complexity testing; technical supervisor.  

Code of Federal Regulations, 2011 CFR

...performing high complexity testing; technical supervisor...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1447...

2011-10-01

150

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

Code of Federal Regulations, 2011 CFR

...performing high complexity testing; clinical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1453...

2011-10-01

151

42 CFR 493.1447 - Condition: Laboratories performing high complexity testing; technical supervisor.  

Code of Federal Regulations, 2012 CFR

...performing high complexity testing; technical supervisor...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1447...

2012-10-01

152

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

Code of Federal Regulations, 2012 CFR

...performing high complexity testing; clinical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1453...

2012-10-01

153

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

Code of Federal Regulations, 2011 CFR

...performing moderate complexity testing; technical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1409...

2011-10-01

154

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

Code of Federal Regulations, 2012 CFR

...performing moderate complexity testing; clinical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1415...

2012-10-01

155

42 CFR 493.1459 - Condition: Laboratories performing high complexity testing; general supervisor.  

Code of Federal Regulations, 2011 CFR

...performing high complexity testing; general supervisor. ...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing High Complexity Testing § 493.1459...

2011-10-01

156

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

Code of Federal Regulations, 2012 CFR

...performing moderate complexity testing; technical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1409...

2012-10-01

157

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

Code of Federal Regulations, 2011 CFR

...performing moderate complexity testing; clinical consultant...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Personnel for Nonwaived Testing Laboratories Performing Moderate Complexity Testing § 493.1415...

2011-10-01

158

Persistence of fipronil and its metabolites in sandy loam and clay loam soils under laboratory conditions.  

PubMed

Samples of sandy loam and clay loam soils were collected from different geographical locations of Punjab. These soils were autoclaved at 120 C at 15 psi for 15 min to destroy the microbes responsible for the degradation of pesticides before initiating the experiment. Each soil was fortified at three levels of fipronil i.e. 100, 200 and 400 mg kg(-1). The whole experiment was conducted at 252 C under laboratory conditions. The residues of fipronil and its metabolites were quantified by Gas Liquid Chromatograph (GLC) and confirmed by Gas Liquid Chromatograph-Mass Spectrometry (GC-MS). The limit of quantification of fipronil and its metabolites was worked out to be 0.001 mg kg(-1). The residues of total fipronil in sandy loam and clay loam after 7 d of its application @ 100 mg kg(-1) were found to be 74.30 and 82.50 mg kg(-1), respectively. Fipronil residues were degraded to amide, sulfone and sulfide in both soils. Desulfinyl metabolite was not found in any of the sample. The persistence of fipronil was found to be more in clay loam soil than sandy loam soil. Total fipronil residues were not found to follow the first order kinetics. Half-life (T1/2) of total fipronil was observed to be 30.10, 33.44 and 33.44 d following application of fipronil @ 100, 200 and 400 mg kg(-1), respectively in sandy loam soil. In clay loam soil, half-life values were observed to be 37.63 d following application of fipronil at all three treatments. PMID:23369635

Mandal, Kousik; Singh, Balwinder

2013-01-29

159

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.

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

2013-01-01

160

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

PubMed

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

2013-09-12

161

Efficacy of quinoa ( Chenopodium quinoa) saponins against golden apple snail ( Pomacea canaliculata) in the Philippines under laboratory conditions  

Microsoft Academic Search

A novel product for managing Pomacea canaliculata, golden apple snail (GAS), containing quinoa saponins (Chenopodium quinoa), was evaluated under laboratory conditions for the protection of newly sprouted rice seeds. Experimental methods mimicked conditions found in direct-seeded rice cultivation in the Philippines, but with a very high GAS density (90snails\\/m2). Protection of newly sprouted seeds was directly proportional to saponin concentration

Ravindra C. Joshi; Ricardo San Martn; Cesar Saez-Navarrete; John Alarcon; Javier Sainz; Mina M. Antolin; Antonio R. Martin; Leocadio S. Sebastian

2008-01-01

162

Toxic cyanobacterial cells containing microcystins induce oxidative stress in exposed tilapia fish ( Oreochromis sp.) under laboratory conditions  

Microsoft Academic Search

The effects of microcystins from cyanobacterial cells on various oxidative stress biomarkers in liver, kidney and gill tissues in freshwater tilapia fish (Oreochromis sp.) were investigated under laboratory conditions. Microcystins are a family of cyclic peptide toxins produced by species of freshwater cyanobacteria (blue-green algae). Fish were exposed to the cyanobacterial cells in two ways: mixed with a commercial fish

ngeles Jos; Silvia Pichardo; Ana I. Prieto; Guillermo Repetto; Carmen M. Vzquez; Isabel Moreno; Ana M. Camen

2005-01-01

163

Moving from the laboratory to the field: Adding natural environmental conditions to toxicology testing  

EPA Science Inventory

While laboratory toxicology tests are generally easy to perform, cost effective and readily interpreted, they have been criticized for being unrealistic. In contrast, field tests are considered realistic while producing results that are difficult to interpret and expensive. To ...

164

42 CFR 493.1361 - Condition: Laboratories performing PPM procedures; testing personnel.  

Code of Federal Regulations, 2012 CFR

...performing PPM procedures; testing personnel. 493.1361 ...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...performing PPM procedures; testing personnel. The...

2012-10-01

165

42 CFR 493.1361 - Condition: Laboratories performing PPM procedures; testing personnel.  

Code of Federal Regulations, 2011 CFR

...performing PPM procedures; testing personnel. 493.1361 ...SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) STANDARDS...REQUIREMENTS Personnel for Nonwaived Testing Laboratories Performing...performing PPM procedures; testing personnel. The...

2011-10-01

166

Elevated Bacterial Abundance in Laboratory-Grown and Naturally Occurring Frost Flowers Under Late Winter Conditions  

NASA Astrophysics Data System (ADS)

Sea ice has been identified as an important microbial habitat, with bacteria and other microbes concentrated in the brine inclusions between ice crystals. Frost flowers, thought to draw brine from underlying sea ice, have not been characterized from a microbial standpoint. To test whether frost flowers serve as an upward vector of bacteria contained within sea ice brines we grew frost flowers in a freezer laboratory (air temperature of -21C) from saline water spiked with the mesophilic (and thus passive under experimental conditions) bacterium Halomonas pacifica. Salinity of melted samples was measured and bacterial abundance determined by epifluorescent microscopy. Bacterial counts scaled to ice-melt volume averaged 2.82 x 106 ml-1 for frost flowers, compared to 9.47 x 105 ml-1 for underlying ice (3 x higher). Bacterial counts also correlated significantly with salinity (maximum value of 62.5 psu) for frost flowers, brine skim, and ice (df = 17, r = 0.59, p < 0.0001). Segregation coefficients were calculated to describe the efficiency of transport of both cells and salt from the starting solution into frost flowers. From these coefficients an enrichment index was calculated to test for bacterial concentration into frost flowers at a different rate than salt. Analysis with a Students T-test (df = 24, t = 0.306, p = .76) indicated that cells and salt were not transported into frost flowers with a significantly different efficiency. To test these findings in the field we then collected frost flowers (and related samples) from new sea ice near Barrow, Alaska in April 2009. Bacterial counts were significantly elevated (again, a 3-fold increase) in natural frost flowers (mean = 2.73 x 105 ml-1) compared to underlying sea ice (mean = 8.46 x 104 cells ml-1). For all field samples collected (frost flowers, underlying brine skim and sea ice, as well as snow), bacterial abundance correlated significantly with salinity (maximum value 124 psu, df = 40, r = 0.60, p < 0.0001). The presence of elevated numbers of bacteria in frost flowers may have implications for the previously observed chemical reactions that take place in them, especially if microbial activity can be shown to occur in this unique low temperature, low water activity microbial habitat.

Bowman, J. S.; Deming, J. W.

2009-12-01

167

Laboratory studies in planetary science and quantitative analysis of evaporation rates under current Martian conditions  

Microsoft Academic Search

Laboratory measurements have been performed that are intended to shed light on several problems in planetary science. Thermoluminescence measurements of ordinary chondrites have been performed as part of an effort to identify the most primitive materials in the solar system. Experiments to study the fractionation of metal and silicate grains on asteroid surfaces have been performed on NASA's microgravity facility

Shauntae Moore

2005-01-01

168

Assessing the Fate of Litter Mercury during Decomposition under Controlled Laboratory Conditions  

Microsoft Academic Search

The goal of this research is to assess the fate of mercury (Hg) in forest litter during decomposition under controlled laboratory incubations and in the field. During decomposition, Hg may be lost to the atmosphere by gaseous elemental mercury evasion, may become soluble and subject to runoff, or may remain sequestered in the remaining litter pool. We are conducting a

A. K. Pokharel; D. Obrist

2009-01-01

169

Laboratory evaluation of PDC drill bits under high speed and high wear conditions  

SciTech Connect

Recently six experimental polycrystalline diamond compact (PDC) bit designs were tested in the laboratory at 100 and 500 rpm in three different types of rock: Nugget Sandstone, Crab Orchard Sandstone, and Sierra White Granite. This paper describes the testing procedures, summarizes the bits' performance and wear characteristics, and correlates these experimental results with specific design options such as rake angle and bit profile.

Hoover, E.R.; Middleton, J.N.

1981-01-01

170

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...

171

Laboratory study of static and dynamic compaction grouting in triaxial condition  

Microsoft Academic Search

This research paper is focused on the fundamental behaviour of applying static and dynamic compaction grouting techniques on completely decomposed granite (CDG) soils in Hong Kong. Using the modified triaxial apparatus and a novel pulse wave generator, laboratory tests were performed to identify the critical controllable factors of static and dynamic compaction grouting techniques in optimizing compaction effectiveness. The distinguishing

S. Y. Wang; D. H. Chan; K. C. Lam; S. K. A. Au

2011-01-01

172

Laboratory study of fault healing and lithification in simulated fault gouge under hydrothermal conditions  

Microsoft Academic Search

Seismic data, geologic observations and laboratory friction studies suggest that faults lithify and strengthen (heal) during the interseismic period of the earthquake cycle. We report on experiments to investigate the influence of healing duration and temperature on the strength and healing rate of simulated faults. Layers of ?m-sized quartz powder were used to simulate granular fault gouge. Gouge layers were

Stephen L. Karner; Chris Marone; Brian Evans

1997-01-01

173

Laboratory investigation of biodegradability of a polyurethane foam under anaerobic conditions  

Microsoft Academic Search

Polyurethane (PU) foams can be used in many remediation applications as an isolation material to prevent the release of hazardous materials into the environment. The integrity of a PU foam was investigated in this study using short-term accelerated laboratory experiments including bioavailability assays, soil burial experiments, and accelerated bioreactors to determine the fate of PU foam in the soil where

Meltem Urgun-Demirtas; Dileep Singh; Krishna Pagilla

2007-01-01

174

Horizontal Transmission of Beauveria bassiana in Anastrepha ludens (Diptera: Tephritidae) Under Laboratory and Field Cage Conditions  

Microsoft Academic Search

The virulence of two products of the fungus Beauveria bassiana (LCPP and Bassianil) on adultAnastrephaludens (Loew) (Diptera: Tephritidae) and their effect on the mating performance of infected males was evaluated in laboratory and eld cage tests. The horizontal transmission capacity of the fungus during copulation or attempted copulation also was quantied using inoculated males as well as the impact of

Jorge Toledo; Sergio E. Campos; Salvador Flores; Pablo Liedo; Juan F. Barrera; Antonio Villaseor; Pablo Montoya

2007-01-01

175

Laboratory Evaluation of a TSI Condensation Particle Counter (Model 3771) Under Airborne Measurement Conditions  

Microsoft Academic Search

The performance of a condensation particle counter (CPC, Model 3771, TSI Inc.), which has a nominal minimum detectable particle size (d50) of 10 nm, has been tested in the laboratory for the purpose of airborne measurements. First, the effects of particle coincidence at concentrations above the upper limit specified by the manufacturer (>10 cm were evaluated. By applying a correction

Nobuyuki Takegawa; Hiromu Sakurai

2011-01-01

176

Universal Similarity  

Microsoft Academic Search

We survey a new area of parameter-free similarity distance measures useful in\\u000adata-mining, pattern recognition, learning and automatic semantics extraction.\\u000aGiven a family of distances on a set of objects, a distance is universal up to\\u000aa certain precision for that family if it minorizes every distance in the\\u000afamily between every two objects in the set, up to the

Paul Vitanyi

2005-01-01

177

Teaching the Principles of Operant Conditioning through Laboratory Experience: The Rat Olympics.  

ERIC Educational Resources Information Center

|Discusses using rat olympics in helping psychology students to overcome their reluctance to condition rats. Working in groups, students enter rats in a number of behaviors (events) which can be shaped using operant conditioning methods and which rats can perform with varying degrees of proficiency. (Author/KC)|

Solomon, Paul R.; Morse, David L.

1981-01-01

178

The energy budget of Porcellio spinicornis Say (Porcellionidae, Isopoda) under laboratory conditions.  

PubMed

The rate of energy flow in Porcellio spinicornis was investigated in a select group of a laboratory population. The consumption, assimilation and production were calculated to be 1 233, 1 002 and 304 cal/year, respectively, in the male, and 1 261, 1 198 and 429 cal/year, respectively, in the female. Ignoring loss due to mortality, and applying the population density of 2 295 m2 in the laboratory colony, the isopod population should consume 2 861.8 kcal m-2 year-1, resulting in an assimilation of 2 524.5 kcal m-2 year-1 and a total productivity of 841.1 kcal m-2 year-1. PMID:6208869

Bukhari, N A; Alikhan, M A

1984-08-01

179

Spawning of zebra mussels (Dreissena polymorpha) and rearing of veligers under laboratory conditions  

USGS Publications Warehouse

The spawning cycle of the zebra mussel, Dreissena polymorpha, is amenable to laboratory manipulations. Techniques are presented that can be used to initiate spawning and rear veligers from fertilized egg to settlement stage. Spawning can be induced in sexually mature mussels by temperature flucuations or by the addition of ripe gametes. Embryonic survival is excellent until the straight-hinge stage when the first wave of mortality occurs, usually due to improper food. The second critical stage of development occurs just prior to settlement when mortality increases again. Veliger mortality averaged over 90% from egg to settlement. The results indicate that obtaining large numbers of veligers for laboratory experiments to be conducted year-round is difficult.

Nichols, S. Jerrine

1992-01-01

180

Laboratory evaluation of PDC drill bits under high-speed and high-wear conditions  

SciTech Connect

Recently, five experimental polycrystalline diamond compact (PDC) bit designs were tested in the laboratory at 100 and 500 rpm in three different types of rock: Nugget sandstone, Crab Orchard sandstone, and Sierra White granite. This study describes the testing procedures, summarizes bit performance and wear characteristics, and correlates these experimental results with specific design options such as rake angle, bit profile, and material selection. 4 refs.

Hoover, E.R.; Middleton, J.N.

1981-12-01

181

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

Microsoft Academic Search

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\\u000a three generations, infestations by both the larval and nymphal stages were performed on chickens (Gallus gallus), wistar rats (Rattus norvegicus), rabbits (Oryctolagus cuniculus),wild mice (Calomys callosus), dogs (Canis familiaris) and opossums (Didelphis albiventris).

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

2002-01-01

182

Emission of nitric oxide and nitrous oxide from soil under field and laboratory conditions  

Microsoft Academic Search

A detailed short-term (12d) laboratory study was carried out to investigate the effects of applying animal urine, fertilizer (ammonium nitrate) and fertilizer+urine on emission of NO and N2O from soil. A complementary 24d field study measured the effect of fertilizer or fertilizer+sheep grazing on NO and N2O emissions from pasture. The data generated were used to interpret the transformations responsible

P. H. Williams; S. C. Jarvis; E. Dixon

1998-01-01

183

Patterns of halite (NaCl) crystallisation in building stone conditioned by laboratory heating regimes  

Microsoft Academic Search

The crystallisation of soluble salts within the pores of the stone is widely recognised as a major mechanism causing the deterioration\\u000a of the stone-built architectural heritage. Temperature, in turn, is one of the main controls on this process, including salt\\u000a precipitation, the pressure of crystallisation and the thermal expansion of salts. Most laboratory experiments on decay generated\\u000a by salts are

Miguel Gomez-Heras; Rafael Fort

2007-01-01

184

Employee motivation in laboratory animal science: creating the conditions for a happy and productive staff.  

PubMed

High rates of employee turnover are the source of a considerable loss of time and resources, but managers are not always aware of the reasons that motivate employees to stay in their positions. The author compares prominent theories of employee motivation and then puts them to the test by surveying 82 cagewashers, animal caretakers, animal technicians, and supervisors working in a laboratory animal facility to determine the job characteristics that motivate them. PMID:16382232

Chick, John F

2006-01-01

185

A comparison of laboratory and pilot-scale fermentations in winemaking conditions  

Microsoft Academic Search

We investigated the influence of the fermenter size on alcoholic fermentation. Experiments were carried out at pilot scale,\\u000a in 100-L fermenters, and at laboratory scale, in stirred and static 1-L fermenters. Two musts, Grenache blanc and Sauvignon,\\u000a were fermented with and without the addition of solid particles from grape musts. Highly clarified must fermentation kinetics\\u000a was strongly affected by the

Erick Casalta; Evelyne Aguera; Christian Picou; Juan-Jose Rodriguez-Bencomo; Jean-Michel Salmon; Jean-Marie Sablayrolles

2010-01-01

186

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. Coss; T. A. Niewold; Ashrafel Said; G. Uilenberg

1989-01-01

187

Chemical reactions involved in the deep fat frying of foods. I. A laboratory apparatus for frying under simulated restaurant conditions  

Microsoft Academic Search

A laboratory apparatus has been designed which can be used to quantitatively collect the volatile decomposition products produced\\u000a during deep fat frying under simulated restaurant conditions. In order to study the chemical reactions of frying fat without\\u000a any inter-reaction with the food fried, moist cotton balls were fried in corn oil.\\u000a \\u000a The oil used for frying was shown to differ

R. G. Krishnamurthy; Tsukasa Kawada; S. S. Chang

1965-01-01

188

Leaching of terbumeton and terbumeton-desethyl from mini-columns packed with soil aggregates in laboratory conditions  

Microsoft Academic Search

Leaching of terbumeton (TER) and terbumeton-desethyl (TED) from mini-columns packed with natural soil aggregates was investigated. Five soil samples from the Champagne area (France) with different physicochemical parameters were used. The soil samples were hand-packed into a 50mm column in laboratory conditions. An aqueous solution of TER or TED was percolated through the column and collected effluents were analyzed for

A. Conrad; O. Dedourge; R. Cherrier; M. Couderchet; S. Biagianti

2006-01-01

189

A Laboratory System for Measurement of the Centimeter-Wave Properties of Gases under Simulated Conditions for Deep Jovian Atmospheres  

Microsoft Academic Search

In recent years, an improved laboratory measurement system was developed at Georgia Tech to measure ammonia and water vapor opacity in a hydrogen\\/helium atmosphere at wavelengths from 1.1 to 20 cm, pressures up to 12 bars and temperatures from 185 to 550 K. This system has provided high-precision measurements over a range of temperature and pressure conditions which correspond to

Paul G. Steffes; B. M. Karpowicz; T. R. Hanley

2007-01-01

190

Response of Predatory Insect Scolothrips takahashii Toward Herbivore-Induced Plant Volatiles Under Laboratory and Field Conditions  

Microsoft Academic Search

We studied the response of a predatory thrips, Scolothrips takahashii, towards herbivore-induced plant volatiles emitted by Lima bean plants infested by two-spotted spider mites Tetranychus urticae (green form). Tests were conducted with a Y-tube olfactometer in the laboratory and with traps under field conditions. The odor of artificially damaged and uninfested Lima bean leaves was not more attractive than clean

Takeshi Shimoda; Junji Takabayashi; Wataru Ashihara; Akio Takafuji

1997-01-01

191

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

192

Subchronic oral toxicity of microcystin in common carp ( Cyprinus carpio L.) exposed to Microcystis under laboratory conditions  

Microsoft Academic Search

The subchronic oral toxicity of microcystin in common carp (Cyprinus carpio L.) was investigated in this study. The fish (mean body weight of 32236g, n=10) were orally exposed to Microcystis by feeding with bloom scum at a dose of 50?g microcystins\\/kg body weight under laboratory conditions for 28 days. Growth assay results showed that microcystin could completely inhibit the growth

Xiao-Yu Li; Ik-Kyo Chung; Jung-In Kim; Jin-Ae Lee

2004-01-01

193

Laboratory studies of ice nucleation by aerosol particles in upper tropospheric conditions  

NASA Astrophysics Data System (ADS)

Ice formation in sulfate, sulfuric acid and black carbon/sulfate aerosol particles under upper tropospheric conditions was studied using a continuous flow thermal diffusion chamber. No clear difference in the homogeneous freezing conditions (temperature, relative humidity) as a function of degree of liquid sulfate neutralization was found, consistent with most other studies. Results support that homogeneous freezing nucleation cannot alone explain observed conditions for cirrus cloud formation. Some types of black carbon (soot) associated with sulfates in mixed particles will induce freezing in preference to the homogeneous process, but only at quite large particle sizes. Small soot produced from burning a particular jet fuel did not show heterogeneous ice nucleation activity until water saturation conditions were exceeded at upper tropospheric temperatures. .

Demott, Paul J.; Rogers, David C.; Kreidenweis, Sonia M.; Chen, Yalei

2000-08-01

194

Maintenance of previously uncultured freshwater archaea from anoxic waters under laboratory conditions  

Microsoft Academic Search

Culture conditions for the maintenance of previously uncultured members of the Archaea thriving in anoxic water layers of stratified freshwater lakes are described. The proposed enrichment conditions, based on\\u000a the use of defined medium composition and the maintenance of anoxia, have been proven effective for the maintenance of the\\u000a archaeal community with virtually no changes over time for periods up

Anna Plasencia; Llus Baeras; Marc Llirs; Emilio O. Casamayor; Carles Borrego

2011-01-01

195

Psychology of learning: a new approach to study behavior of Rhodnius prolixus stal under laboratory conditions.  

PubMed

Conditioning methodologies associated with the psychology of learning are suggested as a new strategy to investigate behavior of the assassin bug Rhodnius prolixus, which is the main vector of Chagas disease in Venezuela. Chagas disease is the fourth leading cause of death in Latin America, as it causes severe chronic illness and approximately 43,000 deaths per year. To illustrate this strategy, two preliminary experiments are reported. In the first, Pavlovian conditioning was examined by pairing an olfactory conditioned stimulus with a temperature unconditioned stimulus. A temperature of 42 degrees C elicits a complex behavioral sequence in R. prolixus consisting of proboscis extension and crawling. Over the course of 12 training trials, this behavioral sequence was not elicited by an olfactory conditioned stimulus. In the second experiment, a latent inhibition paradigm was used to pre-expose R. prolixus to an olfactory conditioned stimulus before pairing the odor with temperature. Over the course of training, an effect of pre-exposure was found. Suggestions for research are discussed and potential conditioned and unconditioned stimuli identified. PMID:16512287

Abramson, Charles I; Romero, Enrique Sulbaran; Frasca, Joseph; Fehr, Ryan; Lizano, Eliecer; Aldana, Elis

2005-12-01

196

Performance of Transient Limiters under Laboratory, Simulated, and Rocket-Triggered Lightning Conditions.  

National Technical Information Service (NTIS)

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 met...

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

1989-01-01

197

Effect of metal ions under laboratory conditions on the entomopathogenic Steinernema carpocapsae (Rhabditida: Steinernematidae)  

Microsoft Academic Search

The effects of sixteen metal ions: Al, Cd, Co(II), Cr(III), Cr(VI), Cu(II), Fe(III), Li, Mg, Mn(H), Mo(VI), Ni(II), Pb(II), Se(IV), V(V), and Zn on the mortality and infectivity of Steinernema carpocapsae were observed in 96 hour laboratory tests. All ions except Cu(II), Pb(II), and Zn even at naturally unrealistic concentrations did not cause the mortality of S. carpocapsae. However, such

Magdalena Jaworska; Jadwiga Sepiol; Piotr Tomasik

1996-01-01

198

Improbability of void growth in aluminum via dislocation nucleation under typical laboratory conditions.  

PubMed

The rate at which dislocations nucleate from spherical voids subjected to shear loading is predicted from atomistic simulation. By employing the latest version of the finite temperature string method, a variational transition state theory approach can be utilized, enabling atomistic predictions at ordinary laboratory time scales, loads, and temperatures. The simulation results, in conjunction with a continuum model, show that the deformation and growth of voids in Al are not likely to occur via dislocation nucleation under typical loadings regardless of void size. PMID:22400757

Nguyen, L D; Warner, D H

2012-01-19

199

Properties of slate mining wastes incubated with grape marc compost under laboratory conditions.  

PubMed

The effect of the addition of spent grape marc compost (GMC) and vermicompost (GMV) as amendments to slate mining wastes was evaluated in a laboratory incubation experiment. Mixtures of slate processing fines (SPF), with three doses of each amendment (4%, 8% and 16% compost, dry weight), plus a control were incubated at 25 degrees C in the laboratory for 90 days. The changes in the chemical and biological properties of the mixtures (pH, total C, total N, inorganic N, available nutrients, microbial biomass carbon and dehydrogenase activity) were investigated during the incubation period, and once it was finished, the phytotoxicity of the mixtures was determined by the germination of Lolium multiflorum Lam. seeds. The addition of the amendments significantly increased the nutrient concentrations of the SPF and enhanced biological activity by increasing microbial biomass and enzymatic activity. Results improved with higher doses; within the composts, GMV showed a better performance than GMC. These results prove the suitability of grape marc-derived amendments for the biochemical amelioration of mining wastes, and highlight the benefits of organic amendment in restoration projects. PMID:18706797

Paradelo, Remigio; Moldes, Ana Beln; Barral, Mara Teresa

2008-08-15

200

Radiometric calibration of SUMER: refinement of the laboratory results under operational conditions on SOHO.  

PubMed

The radiometric calibration of the solar telescope and spectrometer SUMER was carried out in the laboratory before delivery of the instrument for integration into the SOHO (Solar and Heliospheric Observatory) spacecraft. Although this effort led to a reasonable coverage of the wavelength range from 53.70 to 146.96 nm, uncalibrated portions of the sensitivity curves remained before SUMER became operational in early 1996. Thereafter it was possible to perform extrapolations and interpolations of the calibration curves of detector A to shorter, longer, and intermediate wavelengths by using emission line pairs with known intensity ratios. The spectra of the stars alpha and rho Leonis were also observed on the KBr (potassium bromide) photocathode and the bare microchannel plate (MCP) in the range from 120 to 158 nm. In addition, the sensitivity ratios of the KBr photocathode to the bare MCP were determined for many solar lines as well as the H i Lyman and the thermal continua. The results have been found to be consistent with published laboratory data. The uncertainty is +/-15% (1 varsigma) in the wavelength range from 54 to 125 nm. PMID:18259499

Wilhelm, K; Lemaire, P; Feldman, U; Hollandt, J; Schhle, U; Curdt, W

1997-09-01

201

Laboratory evaluation of 10 heat and moisture exchangers using simulated aeromedical evacuation conditions.  

PubMed

Heat and moisture exchangers (HMEs) are used for airway humidification in mechanically ventilated patients and have been evaluated only under hospital conditions. U.S. Air Force aeromedical evacuation transports are performed under rugged conditions further complicated by the cold and dry environment in military aircrafts, and HMEs are used to provide airway humidification for patients. This study evaluated 10 commercial HMEs using a test system that simulated aeromedical evacuation conditions. Although the American National Standards Institute recommends inspired air to be at an absolute humidity value of > or = 30 mg/L for mechanically ventilated patients, the highest absolute humidity by any HME was approximately 20 mg/L. Although none of the HMEs were able to maintain a temperature high enough to achieve the humidity standard of the American National Standards Institute, the clinical significance of this standard may be less important than the relative humidity maintained in the respired air, especially on evacuation flights of short duration. PMID:21702383

Suliman, Huda S; Fecura, Stephen E; Baskin, Jonathan; Kalns, John E

2011-06-01

202

Maintenance of previously uncultured freshwater archaea from anoxic waters under laboratory conditions.  

PubMed

Culture conditions for the maintenance of previously uncultured members of the Archaea thriving in anoxic water layers of stratified freshwater lakes are described. The proposed enrichment conditions, based on the use of defined medium composition and the maintenance of anoxia, have been proven effective for the maintenance of the archaeal community with virtually no changes over time for periods up to 6 months as revealed by a PCR-DGGE analysis. Phylotypes belonging to groups poorly represented in culture collections such as the Deep-Sea Hydrothermal Vent Euryarchaeota (DHVE) and the Miscellaneous Crenarchaeotic Group (MCG) were maintained and selectively enriched when compared to the correspondent indigenous planktonic archaeal community. PMID:20077005

Plasencia, Anna; Baeras, Llus; Llirs, Marc; Casamayor, Emilio O; Borrego, Carles

2010-01-14

203

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.

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

204

Temporal variability in 13C of respired CO2 in a pine and a hardwood forest subject to similar climatic conditions  

NASA Astrophysics Data System (ADS)

The temporal variability in the 13C of ecosystem (Cr), soil (Cs) and foliage (Cf) respired CO2 were contrasted in a 18 m tall evenly aged loblolly pine forest and in a 35 m tall unevenly aged mature second growth deciduous mixed hardwood forest in North Carolina, USA, over a two year period. These two sites are located within a kilometer of each other and are subject to identical climatic and edaphic conditions. Cr varied in response to time lagged vapor pressure deficit (VPD) at both forests. However, the response of Cr to VPD was more dynamic at the pine relative to the hardwood. Cr at the pine forest varied from -31.0 to -26.4 per mill and at the hardwood forest from -26.0 to -27.0 permill during the growing season. Cr at the hardwood forest was 13C enriched during the growing season, on average, by 1.4 permill relative to Cr at the pine forest for the same time periods. Three factors influence these results. Canopy height and composition were different between the two sites, and also at the pine forest Cr values generally were more similar to Cf values, while at the hardwood forest, Cr values were more similar to Cs values. At the hardwood forest, the temporal variability in Cs was less that of Cf and buffered changes in the Cr. The results indicate that within a forest mosaic the vegetation structure needs to be considered for predicting realistic Cr values. Inclusion of a temporally and spatially variable Cr into the atmospheric inversion models will lead to a more realistic estimate of the partitioning of the global carbon uptake into oceanic and terrestrial sinks. Because Cr within each ecosystem varies in response to VPD in a predictable fashion, a variable Cr can be incorporated to better constrain atmospheric inversion models.

Mortazavi, B.; Chanton, J. P.; Prater, J.; Oishi, C.; Oren, R.; Katul, G.

2003-12-01

205

A laboratory exercise to illustrate increased salivary cortisol in response to three stressful conditions using competitive ELISA.  

PubMed

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 illustrate the response of salivary cortisol concentrations to three stressful conditions. Twelve undergraduate students in the General and Comparative Endocrinology course at Iowa State University were subjected to presentation stress, fasting stress, and competition stress to determine their effect on salivary cortisol concentrations. Students had elevated salivary cortisol in response to each of these stresses compared with basal conditions. These results reiterate the importance of glucocorticoids as mediators of the stress response. This study also incorporates the use of the ELISA technique, a modern laboratory tool used to determine the amount of endogenous antigens in plasma or saliva. This laboratory exercise can easily be adapted to fit into already existing physiology and endocrinology curriculums. PMID:17327591

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

2007-03-01

206

Learning and orientation to odor in the bug Rhodnius prolixus Stal 1859 under laboratory conditions.  

PubMed

Two experiments are described investigating learning and orientation in the triatomine Rhodnius prolixus. In experiment 1, Pavlovian conditioning was investigated. The experiment differed from our previous work in that the intensity of the conditioned and unconditioned stimuli were reduced and the number of training trials increased. Once again, no evidence for Pavlovian conditioning was found. In experiment 2, an "orientation arena" was developed in which the orientation of R. prolixus to a human forearm was investigated when an area of the forearm was impregnated with the odor of ruda or almizcle compared to a forearm with no odor. The various paths of the animal from the bottom of the arena until ascending and piercing the forearm, located at the top of the arena, was scored using a grid system and videotaped. The results indicated that under the no odor condition R. prolixus predominately travels in a straight line from the bottom of the arena to the top where the forearm is located. In contrast, the most variable number of paths occurred with exposure to ruda. Exposure to almizcle elicited straight line paths but other paths were evident, although not as variable as that observed with ruda. PMID:18509679

Aldana, E; Abramson, C I; Lizano, E; Vegas, R; Sulbaran-Romero, E

2008-05-30

207

Influence of olive paste preparation conditions on virgin olive oil triterpenic compounds at laboratory-scale  

Microsoft Academic Search

The influence of olive paste preparation conditions on the triterpenic content of virgin olive oils from Arbequina and Picual cultivars was investigated. For this purpose, three sieve diameters of the hammer mill (4, 5, and 6mm), two malaxation temperatures (20 and 30C), and two malaxation times (20 and 40min) were tested. Results obtained showed that for Arbequina oils, a finer

Yosra Allouche; Antonio Jimnez; Marino Uceda; M. Paz Aguilera; Jos Juan Gaforio; Gabriel Beltrn

2010-01-01

208

The Conditions of Permeability: How Shared Cyberworlds Turn into Laboratories of Possible Worlds  

Microsoft Academic Search

Numerous simultaneous paths open in front of the cybernaut, whose person is reflected in the various windows opened on the screen like many fragments of mirror. Yet, the fragmentarity of the online persona does not necessarily imply a disintegration of the self. This paper conducts a philosophical critique of the conditions under which cyberworlds can constitute a psychosocial moratorium virtually

Caterina Desiato

2009-01-01

209

Laboratory study on the survival of water hyacinth under several conditions of heavy metal concentrations  

Microsoft Academic Search

To study the survival and behaviour of water hyacinth [Eichhornia crassipes (Mart.) Solms] under varying conditions of heavy metal concentrations, groups of the plants were grown in different media (distilled water, Nile water, wastewater and different concentrations of heavy metals). Simultaneously, blank experiments were carried out for comparison. Visual changes in the plants observed during each experiment were noted. The

M. E Soltan; M. N Rashed

2003-01-01

210

Evaluation of efficacy of 18 strains of entomopathogenic nematodes (Rhabditida) against Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) under laboratory conditions.  

PubMed

Planococcus citri (Risso, 1813) (Hemiptera: Pseudococcidae) is an important plant virus vector in grapevine crops in Brazil and other countries. The mealybug grows in roots and leaves of the grapes. Entomopathogenic nematodes (EPNs) are efficient control agents against insects associated to the soil and could be applied with the same equipment used for chemical insecticides. The aim of this study was to select effective EPNs for controlling P. citri females in laboratory conditions (251C, UR 6010%). We tested 17 native [Steinernema rarum (6 strains), Steinernema glaseri, Steinernema feltiae, Steinernema riobrave, Steinernema sp., Heterorhabditis bacteriophora (7 strains)] and only one exotic strain (Steinernema carpocapsae ALL). The bioassays were done on Petri dishes infested with females of P. citri, which were sprayed with EPNs juveniles. The strain with larger pathogenicity and virulence in laboratory was H. bacteriophora RS33 (from 69.0% to 92.2% of mortality), native of Rio Grande do Sul. PMID:23458234

Barbosa Negrisoli, Carla Ruth de Carvalho; Negrisoli Jnior, Aldomario Santo; Botton, Marcos; Garcia, Mauro Silveira; Bernardi, Daniel

2013-02-28

211

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

Microsoft Academic Search

The microwave absorbing properties of gaseous sulfuric acid (H2SO4) under Venus atmospheric conditions are investigated. The results are applied to measurements from Mariner 5, Mariner 10, and Pioneer\\/Venus Radio Occultation experiments, to determine abundancies of gaseous sulfuric acid in the Venus atmosphere. The microwave properties of the vapors accompanying liquid H2SO4 are studied to estimate the vapor pressure in an

P. G. Steffes

1984-01-01

212

Bioremediation of endosulfan contaminated soil and waterOptimization of operating conditions in laboratory scale reactors  

Microsoft Academic Search

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

Mathava kumar; Ligy Philip

2006-01-01

213

New Laboratory Measurements of the Centimeter-Wavelength Properties of Ammonia Under Deep Jovian Atmospheric Conditions  

Microsoft Academic Search

Over 800 measurements of the opacity of ammonia have been made in the 5-20 cm wavelength range at pressures ranging from 0.05-96 bars, temperatures from 330-450K, and mixing ratios from 0.05-100% in a hydrogen-helium atmosphere using an ultra-high pressure system. An ammonia absorptivity model that is accurate under very high pressure conditions is necessary for the Juno microwave radiometer (MWR)

Kiruthika Devaraj; P. G. Steffes

2010-01-01

214

Removal and degradation characteristics of quinolone antibiotics in laboratory-scale activated sludge reactors under aerobic, nitrifying and anoxic conditions.  

PubMed

This work describes the removal of 6 quinolone antibiotics from wastewaters under different redox conditions (aerobic, nitrifying and anoxic) through batch experiments in laboratory scale activated sludge reactors using mixed liquor from a membrane bioreactor pilot plant (MBR). The main removal pathways for antibiotics from wastewaters involved in each treatment are described. Mass balances indicated that sorption on sludge played a dominating role in the elimination of antibiotics. Sorption potential depended on the redox conditions, being lower in nitrifying (Kd, 414-876 L kg(-1)) and anoxic (Kd, 471-930 L kg(-1)) sludge in comparison with aerobic sludge (Kd, 534-1137 L kg(-1)). Kd was higher for piperazinylic quinolones. Redox conditions also influenced biodegradation, a secondary pathway, which followed first-order kinetics with degradation rates constants ranging from 1.810(-3) to 8.210(-3) h(-1). Biodegradation rates under anoxic conditions were negligible. The experimental results have also demonstrated much higher removal efficiency by biodegradation (36.2-60.0%) under nitrifying conditions in comparison with aerobic conditions (14.9-43.8%). The addition of allylthiourea, an ammonia monooxygenase inhibitor, inhibited nitrification completely and reduced significantly the biodegradation of target antibiotics (16.5-29.3%). The residual biodegradation in the presence of allylthiourea may be due to the activity of heterotrophs in the enriched nitrifier culture. The removal of the selected antibiotics under the studied redox conditions depended significantly on the bacteria composition of the sludge. These results suggest that despite the known persistence of this group of antibiotics it is possible to enhance their degradation using nitrifying conditions, which at adequate working conditions as high SRT, typical in MBR, become a promising alternative for improving quinolones removal from environment. PMID:23507246

Dorival-Garca, N; Zafra-Gmez, A; Navaln, A; Gonzlez-Lpez, J; Hontoria, E; Vlchez, J L

2013-03-15

215

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

216

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

217

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

218

Parasitism of Tuta absoluta (Lepidoptera, Gelechiidae) by Pseudapanteles dignus (Hymenoptera, Braconidae) under laboratory conditions.  

PubMed

Laboratory studies were conducted to measure selected life history traits and the functional response of the parasitoid Pseudapanteles dignus (Muesebeck), a major enemy of Tuta absoluta (Meyrick) in tomato crops in South America. Newly mated P. dignus females were individually exposed to 10 host larvae in mines for 24 h. We determined developmental time from egg to pupal formation and pupal stage duration, female adult life span, fecundity, reproductive period, daily parasitism rate, and sex ratio of offspring. For the functional response experiment, treatments consisted of six host densities: 3, 5, 7, 10, 15, 20, or 30 larvae. The number and proportion of parasitized hosts were calculated for each density. The shape of the functional response curve was analyzed by logistic regression. P. dignus females attacked hosts daily, exhibiting modest lifetime fecundity (approximately 32 parasitized hosts per female) and a female-biased offspring sex ratio. Female adult life span was 36 d. P. dignus showed a type I functional response within the range of host densities tested. We observed that females detect and parasitize the host within a wide range of densities, including low densities. The functional response curve reached an asymptote at a mean density of six hosts per day and seemed not to be egg-limited. Percent parasitism was approximately 30%. The ecological implications of the results in relation to the potential of P. dignus for the biological control of T. absoluta in tomato are discussed. PMID:17716480

Luna, Mara G; Snchez, Norma E; Pereyra, Patricia C

2007-08-01

219

A new apparatus to study behavior of triatomines under laboratory conditions.  

PubMed

A new apparatus is described to study a wide range of behavior in the vectors of Chagas's disease. The device is relatively inexpensive and easy to construct. A wide range of independent variables can be studied, including potential attractants, repellents, blood, and blood products under controlled conditions. Various experimental designs can be used including the investigation of learning and social behavior. The apparatus can also be used for the mass rearing of triatomines. The efficacy of the apparatus is illustrated in experiments on the attraction of odors and on fecundity. PMID:16050646

Aldana, Elis; Otalora, Fernando; Abramson, Charles I

2005-06-01

220

Effect of pH on the fate of fenazaquin in soil and water under laboratory-simulated condition  

Microsoft Academic Search

The persistence of fenazaquin (4-t-butylphenylethyl quinazolin-4-yl ether) was studied in three different soils, namely, Gangetic alluvial (pH 6.9), laterite (pH 5.3), and terai (pH 5.1) soil and in water at three different pH values (4.0, 7.0, and 9.2) under laboratory-simulated condition and samples were analyzed upto 60 days at regular intervals. Fenazaquin was applied at 5 and 10 g g

Jayati Bhattacharyya; Sukhendu Kumar Pramanik; Hemanta Banerjee; Anjan Bhattacharyya

2010-01-01

221

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

222

Factors affecting growth and survival of the asiatic clam Corbicula sp. under controlled laboratory conditions  

SciTech Connect

Growth of Corbicula sp. was determined in relation to food supply, water temperature, and clam size as an aid to researchers conducting chronic effects toxicity studies. Water temperatures for the two 84-day test series were 10, 20, and 30/sup 0/C. Linear models provided good relationships (r/sup 2/ > 0.90) between clam shell length (SL), total weight (TW), and wet/dry tissue weights. Clam growth was minimal during low phytoplankton densities (approx. 300 cells/ml), and all three size groups lost weight at 20 and 30/sup 0/C. Mortality of small clams at 30/sup 0/C was 100% after 71 days. At phytoplankton densities > 1000 cells/ml, overall differences in growth with respect to clam size and temperature were detectable at p < 0.01; growth of all clam groups was greatest at 30/sup 0/C. Small clams exhibited the greatest absolute increase in mean shell length at all test temperatures, and weight gains were similar to those of medium and large clams.

Double, D.D.; Daly, D.S.; Abernethy, C.S.

1983-04-01

223

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

224

Application of laboratory experiments to assess the error introduced by the imposition of "wall" boundary conditions in shelf models  

NASA Astrophysics Data System (ADS)

For mathematical and numerical reasons the physical boundary condition of regularity of solutions (i.e. finite amplitude) at the singular point of vanishing water depth (the shoreline) imposed on wavelike solutions on the continental shelf is replaced by "no normal flow" condition in analytical and numerical studies of continental shelf waves. This "no normal flow" condition that circumvents the mathematical subtlety associated with the singularity of the equations at the shoreline applies only to channel problems where a wall bounds the flow on the shoreline side. To assess the ramifications of this simplification on the phase speeds and radial (cross-shore) structure of the solutions, data from laboratory experiments are compared with predictions of models that employ the two boundary conditions. The phase speed and radial structure are measured in experiments carried out in a turntable with linearly sloping bottom in which the mean water depth vanishes on the shallow side and waves with known frequencies are generated at a point along the perimeter. The dispersion relation and wave's radial structure are estimated by following particles floating in the water; the measured dispersion relation agrees well with that predicted by a theory that employs the shelf boundary condition and disagrees with the prediction of a theory that employs the channel conditions. This disagreement between the dispersion relation predicted by the channel theory and that predicted by the shelf theory is relevant to typical frequencies that are observed on continental shelves. Although the shelf break condition does not affect the dispersion relation, better agreement is found between the predicted and measured velocity structure when a flat bottom is assumed there instead of a wall.

Cohen, Yair; Paldor, Nathan; Sommeria, Jol

225

Lack of glyphosate resistance gene transfer from Roundup Ready soybean to Bradyrhizobium japonicum under field and laboratory conditions.  

PubMed

A field study was conducted at the Russell E. Larson Agricultural Research Center to determine the effect of transgenic glyphosate-resistant soybean in combination with herbicide (Roundup) application on its endosymbiont Bradyrhizobium japonicum. DNA of bacteroids from isolated nodules was analysed for the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (CP4-EPSPS) DNA sequence using polymerase chain reaction (PCR). To further assess the likelihood that the EPSPS gene may be transferred from the Roundup Ready (RR) soybean to B. japonicum, we have examined the natural transformation efficiency of B. japonicum strain 110spc4. Analyses of nodules showed the presence of the transgenic EPSPS DNA sequence. In bacteroids that were isolated from nodules of transgenic soybean plants and then cultivated in the presence of glyphosate this sequence could not be detected. This indicates that no stable horizontal gene transfer (HGT) of the EPSPS gene had occurred under field conditions. Under laboratory conditions, no natural transformation was detected in B. japonicum strain 110spc4 in the presence of various amounts of recombinant plasmid DNA. Our results indicate that no natural competence state exists in B. japonicum 110spc4. Results from field and laboratory studies indicate the lack of functional transfer of the CP4-EPSPS gene from glyphosate-tolerant soybean treated with glyphosate to root-associated B. japonicum. PMID:22351985

Isaza, Laura Arango; Opelt, Katja; Wagner, Tobias; Mattes, Elke; Bieber, Evi; Hatley, Elwood O; Roth, Greg; Sanjun, Juan; Fischer, Hans-Martin; Sandermann, Heinrich; Hartmann, Anton; Ernst, Dieter

226

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 -15C. Water suspensions of these bacteria were directly sprayed into the cloud chamber of the AIDA facility of Forschungszentrum Karlsruhe at a temperature of -5.7C. 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 -5.7C. 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 -11C. 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 -11C 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 -8C.

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

2008-10-01

227

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 -15C. 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 -11C. 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 -11C 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 -8C.

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

2008-04-01

228

Effect of thermal shock on the decomposition of rocks under controlled laboratory conditions  

NASA Astrophysics Data System (ADS)

The major factor determining the rate of weathering of a given rock are the climatic conditions of the surrounding environment, most notably type and amount of precipitation and temperature. For the latter, average annual temperature and where applicable, the frequency of freezing and thawing are often considered to be relevant for weathering. The rate of temperature change is mostly ignored. However, a rapid change in temperature, referred to as thermal shock could have more severe consequences of rock deterioration then gradual heating and cooling of rocks is gradual. Thermal shock induces a stress of such a magnitude that the material is unable to adjust fast enough and so it breaks down. The aim of this study is to examine the importance of mechanical decomposition of rocks when treated with thermal shock by freezing. The rate of decomposition of rocks of various sizes was measured based on their weight loss. In addition, they were immersed in water after freezing and the electrical conductivity and pH of the water were measured as an index for thermal-shock induced micro-fracturing. Samples of three rock types were chosen for the experiment: limestone, tuffaceous rock and basalt. Samples were examined in two separate cycles: (i) 24h immersion in ultra-clean water followed by 24h drying at 30o and (ii) 24h immersion, 24h temperature shock by freezing at -20?C and 6h thawing. Each cycle was repeated approximately 20 times. In each cycle three different sizes of rock were examined: <16mm, 16-8mm and 8-5mm. Limestone mass decreased for both cycles, although more distinctly after repeated thermal shocks. Furthermore, the rate of decay decreased with increasing rock size. Tuffaceous rock exposed to cycle (i) also showed a significant weight loss. Somewhat surprisingly, the mass of the tuffaceous rock exposed to thermal shock increased by about 13% in all sample size groups. It is possible that pore volume increased during experiment and that the rocks became capable of absorbing more water, but the rock was elastic enough not to break under stress. On the basalt, as expected, the rate of weight loss was the smallest. Cylce (ii) samples also showed more intensive mass reduction. Electrical conductivity and pH of the immersion water were constant throughout the experiment and did not change with the number of cycles. This implies that no significant chemical disintegration occurred. The results show that thermal shock can have a rock type-specific effect on physical weathering. The lacking effect on chemical weathering is expected due to the design of the experiment. Under natural conditions, with non-pH neutral water, the declining rock stability, indicated by the loss of mass, especially of the limestone, will mostly likely also enhance leaching and thus chemical weathering.

Kasanin-Grubin, Milica; Vezmar, Tijuana; Kuhn, Nikolaus J.

2013-04-01

229

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.

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

2012-01-01

230

Laboratory test methods to determine the degradation of plastics in marine environmental conditions.  

PubMed

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

2012-06-21

231

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

232

Value of Laboratory Tests in Employer-Sponsored Health Risk Assessments for Newly Identifying Health Conditions: Analysis of 52,270 Participants  

Microsoft Academic Search

BackgroundEmployer-sponsored health risk assessments (HRA) may include laboratory tests to provide evidence of disease and disease risks for common medical conditions. We evaluated the ability of HRA-laboratory testing to provide new disease-risk information to participants.Methodology\\/Principal FindingsWe performed a cross-sectional analysis of HRA-laboratory results for participating adult employees and their eligible spouses or their domestic partners, focusing on three common health

Harvey W. Kaufman; Fred R. Williams; Mouneer A. Odeh

2011-01-01

233

Visual search for real world targets under conditions of high targetbackground similarity: Exploring training and transfer in younger and older adults  

Microsoft Academic Search

Real world visual search tasks often require observers to locate a target that blends in with its surrounding environment. However, studies of the effect of targetbackground similarity on search processes have been relatively rare and have ignored potential age-related differences. We trained younger and older adults to search displays comprised of real world objects on either homogenous backgrounds or backgrounds

Mark B. Neider; Walter R. Boot; Arthur F. Kramer

2010-01-01

234

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

235

Molluscicidal activity of Physalis angulata L. extracts and fractions on Biomphalaria tenagophila (d'Orbigny, 1835) under laboratory conditions.  

PubMed

The main objective of this research is to evaluate the molluscicide activity of Physalis angulata L. Biomphalaria tenagophila specimens under laboratory conditions. Extracts and fractions were supplied by the Laborat rio de Qu mica de Produtos Naturais, Farmanguinhos-Fiocruz. Experiments were performed according to the methodology described by the World Health Organization for molluscicide tests using the concentrations from 0.1 to 500 mg/l of the extracts, fractions and of a pool of physalins modified steroids present in this species. The results show that ethyl acetate and acetone extracts from the whole plant, the ethanolic extracts of the roots and the physalins pool from stems and leaves were active. Only the whole plant extracts were available in sufficient quantity for the determination of LD50 and LD90 values. PMID:12886428

dos Santos, Jos Augusto A; Tomassini, Therezinha Coelho B; Xavier, Deise Cristina Drummond; Ribeiro, Ivone Maria; da Silva, Melissa Teixeira G; de Morais Filho, Zenildo Buarque

2003-07-18

236

Locally similar solutions for hydromagnetic and thermal slip flow boundary layers over a flat plate with variable fluid properties and convective surface boundary condition  

Microsoft Academic Search

This paper presents heat transfer process in a two-dimensional steady hydromagnetic convective flow of an electrically conducting\\u000a fluid over a flat plate with partial slip at the surface of the boundary subjected to the convective surface heat flux at\\u000a the boundary. The analysis accounts for both temperature-dependent viscosity and temperature dependent thermal conductivity.\\u000a The local similarity equations are derived and

M. M. Rahman

237

Modeling of salt-water migration through spod-podzolic soils under the field and laboratory conditions  

NASA Astrophysics Data System (ADS)

The assessment of highly mineralized water influence on soils is an important issue in the contemporary world. Various regions with different conditions are exposed to salt-affected soils forming. Salinization of soils is a complex process of the chemical and physical properties changes. Therefore the chain of the laboratory and field experiments should be done in order to assess the main factors promoting highly mineralized water migration. In addition to it modelling is a good way to understand and evaluate main chemical and physical transformations in soils. The chain of experiments was done to assess salt water movement in spod-podzolic soils under field and laboratory conditions. The main goals were to evaluate the rate of salt water movement through soils and to estimate velocity of the desalinization process. Field experiment was conducted on spod-podzolic soils of Kaliningrad region. There were 4 sites measuring 20*25 cm watering with salt water in amount of 5 liters per each area. The mineralization of the solution was 100 g/l. In addition to the salt affected sites, 2 non polluted grounds were assessed too. Soils samples were collected in the period of 1 week, 1 month, 3 month and 1 year after the spill had been done. The samples were taken each 10 cm 110 cm deep and in double repeatability. Main chemical and physical parameters, such as volume water content, pH, conductivity, amount of calcium ion, magnesium, sodium, and chlorite in soils etc. were measured in each sample. The second experiment was conducted to evaluate the rate of soils solutions transformation under the laboratory conditions. Organic horizon was taken from the field and was stuffed in columns with 1.0 g/cm3 density. There were 16 columns with 4 cm diameter. 14 columns were showered with salt water with the same mineralization as in the field experiment. The amount of salt water injected in columns was 104 mm per one sample which is equal to the salt water volume spilled per one area in the previous experiment. Also there were 2 columns as a verification variant contained pure soil. Each column was washed off with different amount of distilled water. The total volume of the pure solution was equal to the mean amount of the annual precipitation in the region of the field experiment. The main physical and chemical properties were measured in soils samples as well in the first experiment. In addition to it the complex assessment of soil's water were made. The experiments revealed the fast rate of salinization-desalinization processes in spod-podzolic soils of the coniferous areas in Kaliningrad region. The maximum values of conductivity were observed at the end of 1 week period and made up more than 2000 mSm/cm in top soils horizons. Furthermore the desalinization of the soils took place in both field and laboratory experiments a year after the spill. The reported study was partially supported by RFBR, research project No 12-05-31088 mol_a.

Ronzhina, Tatiana

2013-04-01

238

Temporal variability in (13)C of respired CO(2) in a pine and a hardwood forest subject to similar climatic conditions.  

PubMed

Temporal variability in the (13)C of foliage (delta(13)C(F)), soil (delta(13)C(S)) and ecosystem (delta(13)C(R)) respired CO(2) was contrasted between a 17.2-m tall evenly aged loblolly pine forest and a 35-m tall unevenly aged mature second growth mixed broadleaf deciduous forest in North Carolina, USA, over a 2-year period. The two forests are located at the Duke Forest within a kilometer of each other and are subject to identical climate and have similar soil types. The delta(13)C(F), collected just prior to dawn, was primarily controlled by the time-lagged vapor pressure deficit (VPD) in both stands; it was used for calculating the ratio of intercellular to ambient CO(2) ( Ci/ Ca). A remarkable similarity was observed in the relationship between Ci/ Ca and time-lagged VPD in these two forests despite large differences in hydraulic characteristics. This similarity emerged as a result of physiological adjustments that compensated for differences in plant hydraulic characteristics, as predicted by a recently proposed equilibrium hypothesis, and has implications to ecophysiological models. We found that in the broadleaf forest, the delta(13)C of forest floor CO(2) efflux dominated the delta(13)C(R), while in the younger pine forest, the delta(13)C of foliage respired CO(2) dominated delta(13)C(R). This dependence resulted in a more variable delta(13)C(R) in the pine forest when compared to the broadleaf forest due to the larger photosynthetic contribution. Given the sensitivity of the atmospheric inversion models to delta(13)C(R), the results demonstrate that these models could be improved by accounting for stand characteristics, in addition to previously recognized effects of moisture availability, when estimating delta(13)C(R). PMID:15340829

Mortazavi, Behzad; Chanton, Jeffrey P; Prater, James L; Oishi, A Christopher; Oren, Ram; Katul, Gabriel

2004-08-31

239

A comparison of the bioaccumulation potential of three freshwater organisms exposed to sediment-associated contaminants under laboratory conditions.  

PubMed

In the field of sediment quality assessment, increased support has been expressed for using multiple species that represent different taxa, trophic levels, and potential routes of exposure. However, few studies have compared the bioaccumulation potential of various test species over a range of sediment contaminants (hydrophobic organics and metals). As part of the development and standardization of a laboratory bioaccumulation method for the Ontario Ministry of the Environment, the oligochaete Lumbriculus variegatus, mayfly nymph Hexagenia spp., and juvenile fathead minnow Pimephales promelas were exposed to a variety of field-contaminated sediments (n?=?10) to evaluate their relative effectiveness for accumulating different contaminants (e.g., dichlorodiphenyltrichloroethane [DDT] and metabolites, polychlorinated biphenyls [PCBs), polycyclic aromatic hydrocarbons [PAHs), polychlorinated dibenzo-p-dioxins and dibenzofurans [PCDD/Fs), and heavy metals). Bioaccumulation was usually highest in L. variegatus but also most variable within and (relative measures) between sediments. Bioaccumulation was similar between L. variegatus and Hexagenia spp. in most of the sediments tested. Significant differences in bioaccumulation between species were observed for DDT, dichlorodiphenyldichloroethane (DDD), PAHs, and PCDD/Fs. The present study indicates that species-specific differences in bioaccumulation may, but do not always, exist and can vary with contaminant and sediment type. The choice of test species or combination to use in a standard test method may depend on the objectives of the sediment quality assessment and data requirements of an ecological risk assessment. The results of the present study provide insight for selection of test species and validation of laboratory methods for assessing bioaccumulation with these species, as well as valuable information for interpreting results of bioaccumulation tests. PMID:21194176

Van Geest, Jordana L; Poirier, David G; Solomon, Keith R; Sibley, Paul K

2011-02-10

240

Influence of light colours on growth and stress response of rainbow trout (Oncorhynchus mykiss) under laboratory conditions.  

PubMed

The influence of light colours on growth and stress response in rainbow trout Oncorhyncus mykiss (15.16??0.29?cm; 32.27??1.18?g) was studied. Fish were reared in 16 glass aquaria (140??30??80?cm) each with 12 fish under one of four different lighting spectra: yellow (546?nm), red (605?nm), blue (470?nm) and white (full spectrum, control). Experiments lasted 125?days. The stress response was evaluated by measuring cortisol levels. Body weight and total length of the fish reared under yellow light were greater compared with the other colour regimes while feed conversion ratio significantly lowers. Condition factor and specific growth rate, however, were not differentiated among experimental light treatments. Stressed fish showed lower cortisol levels under yellow light compared with other light exposures. The study indicates that under laboratory conditions, rainbow trout grow best under yellow light and that yellow light lowers the stress-induced cortisol response in this fish species. PMID:22017568

Heydarnejad, M Saeed; Parto, M; Pilevarian, A A

2011-10-22

241

Similar quartz crystallographic textures in rocks of continental earth's crust (by neutron diffraction data): III. Relation of quartz texture types with means and conditions of texture formation  

SciTech Connect

Examples of different rocks collected in different regions of the continental earth's crust are presented. Groups of quartz crystallographic textures of the same type are selected for these rocks. The relationship between the types of textures and the physical means and conditions of their formation is analyzed. The effect of the {alpha}-{beta} phase transition in quartz on the texture transformations in rocks is considered.

Nikitin, A. N., E-mail: nikitin@nf.jinr.ru; Ivankina, T. I. [Joint Institute for Nuclear Research (Russian Federation); Ullemeyer, K. [Universitaet Kiel, Institut fuer Geowissenschaften (Germany); Vasin, R. N. [Joint Institute for Nuclear Research (Russian Federation)

2008-09-15

242

Similar phenotypes of Girdin germ-line and conditional knockout mice indicate a crucial role for Girdin in the nestin lineage.  

PubMed

Girdin is an Akt substrate and actin-binding protein. Mice with germ-line deletions of Girdin (a non-conditional knockout, (ncKO)) exhibit complete postnatal lethality accompanied by growth retardation and neuronal cell migration defects, which results in hypoplasia of the olfactory bulb and granule cell dispersion in the dentate gyrus. However, the physiological and molecular abnormalities in Girdin ncKO mice are not fully understood. In this study, we first defined the distribution of Girdin in neonates (P1) and adults (6months or older) using ?-galactosidase activity in tissues from ncKO mice. The results indicate that Girdin is expressed throughout the nervous system (brain, spinal cord, enteric and autonomic nervous systems). In addition, ?-galactosidase activity was detected in non-neural tissues, particularly in tissues with high tensile force, such as tendons, heart valves, and skeletal muscle. In order to identify the cellular population where the Girdin ncKO phenotype originates, newly generated Girdin flox mice were crossed with nestin promoter-driven Cre transgenic mice to obtain Girdin conditional knockout (cKO) mice. The phenotype of Girdin cKO mice was almost identical to ncKO mice, including postnatal lethality, growth retardation and decreased neuronal migration. Our findings indicate that loss of Girdin in the nestin cell lineage underlies the phenotype of Girdin ncKO mice. PMID:22974978

Asai, Masato; Asai, Naoya; Murata, Ayana; Yokota, Hirofumi; Ohmori, Kenji; Mii, Shinji; Enomoto, Atsushi; Murakumo, Yoshiki; Takahashi, Masahide

2012-09-04

243

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests...Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests...diagnostic tests. All diagnostic x-ray tests, diagnostic...

2009-10-01

244

42 CFR 410.32 - Diagnostic x-ray tests, diagnostic laboratory tests, and other diagnostic tests: Conditions.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Diagnostic x-ray tests, diagnostic laboratory tests...Services § 410.32 Diagnostic x-ray tests, diagnostic laboratory tests...diagnostic tests. All diagnostic x-ray tests, diagnostic...

2010-10-01

245

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

...research; inert solvents for chemical reactions, as a carrier or laboratory chemical and other critical analytical...road-paving materials; and c. Forensic finger printing. Production...laboratory and analytical chemicals shall contain only...

2010-07-01

246

Whole-exome sequencing identified a homozygous FNBP4 mutation in a family with a condition similar to microphthalmia with limb anomalies.  

PubMed

Microphthalmia with limb anomalies (MLA), also known as Waardenburg anophthalmia syndrome or ophthalmoacromelic syndrome, is a rare autosomal recessive disorder. Recently, we and others successfully identified SMOC1 as the causative gene for MLA. However, there are several MLA families without SMOC1 abnormality, suggesting locus heterogeneity in MLA. We aimed to identify a pathogenic mutation in one Lebanese family having an MLA-like condition without SMOC1 mutation by whole-exome sequencing (WES) combined with homozygosity mapping. A c.683C>T (p.Thr228Met) in FNBP4 was found as a primary candidate, drawing the attention that FNBP4 and SMOC1 may potentially modulate BMP signaling. PMID:23703728

Kondo, Yukiko; Koshimizu, Eriko; Megarbane, Andre; Hamanoue, Haruka; Okada, Ippei; Nishiyama, Kiyomi; Kodera, Hirofumi; Miyatake, Satoko; Tsurusaki, Yoshinori; Nakashima, Mitsuko; Doi, Hiroshi; Miyake, Noriko; Saitsu, Hirotomo; Matsumoto, Naomichi

2013-05-23

247

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

NASA Astrophysics Data System (ADS)

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 Schrdinger 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 Schrdinger 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 L2-operator norm.

Mantile, Andrea

2013-08-01

248

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 H 2O vapor in a H 2/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 H 2O (at maximum pressure) ranged from 0.19% to 3.6% with some additional measurements of pure H 2O. These results have enabled development of the first model for the opacity of gaseous H 2O in a H 2/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

249

Predatory Potential of Euseius alatus (Phytoseiidae) on Different Life Stages of Oligonychus ilicis (Tetranychidae) on Coffee Leaves Under Laboratory Conditions.  

PubMed

This study evaluated the predatory capacity of Euseius alatus (DeLeon) as a biological control agent of the pest mite Oligonychus ilicis (McGregor) on coffee leaves under laboratory conditions, using arenas containing 25 O. ilicis per coffee (Coffea arabica) leaf to one specimen of each stage of the predator mite. The functional response and oviposition rate of adult females of E. alatus were evaluated on coffee leaf arenas and offered from 1 to 125 immature stages of O. ilicis per arena. The number of preys killed and the number of eggs laid by the predator were evaluated every 24h during 8days. The preys consumed were daily replaced. Male and female adults of E. alatus were the most efficient in killing all developmental stages of O. ilicis. Larvae and nymphs of O. ilicis were the most consumed by all stages of the predatory mite. The functional response and oviposition rates of E. alatus increased as the prey density increased, with a positive and highly significant correlation. Regression analysis suggested a type II functional response, with a maximum predation of 22 O. ilicis/arena and a maximum oviposition rate of 1.7 eggs/day at a density of 70 O. ilicis/arena. PMID:23949753

de Toledo, M A; Reis, P R; da Silveira, E C; de P Marafeli, P; de Souza-Pimentel, G C

2013-01-30

250

Effect of host plants on developmental time and life table parameters of Carposina sasakii (Lepidoptera: Carposinidae) under laboratory conditions.  

PubMed

Studies were designed to examine the effects of host plants (apricot, Prunus armeniaca L.; plum, Prunus salicina L.; peach, Prunus persica L.; jujube, Zizyphus jujuba Will.; apple, Malus domestica Mill.; and pear, Pyrus sorotina Will) on the development and life table parameters of the peach fruit moth, Carposina sasakii Matsumura (Lepidoptera: Carposinidae) under laboratory conditions. Peach fruit moth developed faster (12.48 d) and had the highest preimaginal survival rate (50.54%) on plum compared with the other host plants. Adult longevity was significantly longer on jujube for both female and male moths. Adult females from larvae reared on jujube and peach laid significantly greater numbers of eggs (214.50 and 197.94 eggs per female, respectively) compared with those reared on the other four host plants. Life-table parameters were calculated for each host plant and compared by jackknife procedures. The intrinsic rate of natural increase (r(m)) was significantly greatest on plum (0.1294 eggs per female per d), followed by jujube and apricot (0.1201 and 0.1128 eggs per female per d), respectively. Implications of the various measures of population performance are discussed. PMID:22507008

Lei, Xihong; Li, Dingxu; Li, Zheng; Zalom, Frank G; Gao, Lingwang; Shen, Zuorui

2012-04-01

251

Creating conditions similar to those that occur during exposure of cells to microgravity induces apoptosis in human lymphocytes by 5-lipoxygenase-mediated mitochondrial uncoupling and cytochrome c release  

Microsoft Academic Search

Creating conditions similar to those that occur during exposure of cells to microgravity induced a sixfold increase of apoptotic bodies and DNA fragments in human lymphocytes, paralleled by an early (within 2 h) fourfold increase in 5-li- poxygenase (5-LOX) activity and a fivefold de- crease in mitochondrial membrane potential and increase in cytochrome c release (within 4 and 8 h,

Mauro Maccarrone; Natalia Battista; Mariantonia Meloni; Monica Bari; Grazia Galleri; Proto Pippia; Augusto Cogoli; Alessandro Finazzi-Agro

2003-01-01

252

conditions  

Microsoft Academic Search

Real-time scheduling is both based on a broad theoretical background and available through a multitude of tools and infrastructures. The central input parameters to this discipline are the demand for execution time and the real- time conditions given as deadlines or periods. The former has attracted a lot of research efforts, mainly in the scope of worst case execution time

Dieter Z

253

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.

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

2013-01-01

254

Conditions  

Microsoft Academic Search

A shallow, RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine)- contaminated aquifer at Naval Submarine Base Bangor has been characterized as predominantly manganese-reducing, anoxic with local pockets of oxic conditions. The potential contribution of microbial RDX degradation to localized decreases observed in aquifer RDX concentrations was assessed in sediment microcosms amended with (U- 14 C) RDX. Greater than 85% mineralization of 14 C-RDX to 14 CO2

Paul M. Bradley; Richard S. Dinicola

255

Laboratory Simulation of Biogeochemical Interactions Between Cyanobacterium-Growth and CaCO3 Deposition: Implications for Carbon Accumulation Under Extreme Atmospheric Conditions of Precambrian Earth  

NASA Astrophysics Data System (ADS)

The atmosphere of Precambrian Earth was characterized by high PCO2, low PO2, and high violent UV radiation. To better understand the interaction between cyanobacterium-growth and CaCO3 deposition in such extreme environments, we grew Oscillatoria tenuis, a prokaryotic alga that is morphologically similar to micro-fossils found in Precambrian chert, in the laboratory under controlled temperature and patial presure of CO2. During algal cell growth, oxygen was absorbed continously by chromous chloride oxygen-absorbent and the levels of PCO2 were controlled by adding different amounts of HCO3- (NaHCO3) in culture medium with initial pH 7.4. Our observation indicates that PCO2 excerises the first order of control on the accumulation of cyanobaterium biomass. Under 100,000 Pa of PCO2, the growth rate of cyanobaterium increases along with the elevation of CO2 partial pressure; however, when PCO2 is higher than 100,000 Pa, the increase of PCO2 results in the decrease of cyanobacterium biomass. On the other hand, photosynthesis of cyanobacteria controls CaCO3 deposition via the function of adjusting pH in the solution. In a 5 day cell growth experiment with PCO2 controlled at about 50,000 Pa and additional 0.0001, 0.001, 0.01, 0.1 and 1.0 M Ca2+ input separately at speed of 2.5 ml/h, the largest total biomass of cyanobacterium (896 mg/L) including living suspension cells and deposited cells was obtained when Ca2+ input was maintained at 0.01 M with 2.5 ml/h. Otherwise, less Ca2+ input resulted in more living suspension cells and less deposited cells. More Ca2+ input resulted in less living suspension cells and more deposited cells. At last both conditions were not good for cell growth and accumulation of organic matter in carbonate deposition in long term. Our laboratory simulation illustrates that the Ca2+ input is critical to CaCO3 deposition and such controls are indirectly enforced through the accumulation of cyanobacteria biomass under a warm, anoxic and high pCO2 atmospheric condition during a part of Precambrian time.

Wu, Q.; Chen, L.; Chen, G.; Yang, H.

2004-05-01

256

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

257

Photochemical transformation of atrazine and formation of photointermediates under conditions relevant to sunlit surface waters: Laboratory measures and modelling.  

PubMed

By combination of laboratory experiments and modelling, we show here that the main photochemical pathways leading to the transformation of atrazine (ATZ, 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) in surface waters would be direct photolysis, reaction with OH and with the triplet states of chromophoric dissolved organic matter ((3)CDOM*). Reaction with (3)CDOM* would be favoured by elevated water depth and dissolved organic carbon content, while opposite conditions would favour direct photolysis and OH reaction. Desethylatrazine (DEA, 4-amino-2-chloro-6-isopropylamino-1,3,5-triazine) was the main detected intermediate of ATZ phototransformation. Its formation yield from ATZ (ratio of DEA formation to ATZ transformation rate) would be 0.930.14 for OH, 0.550.05 for (3)CDOM*, and 0.200.02 for direct photolysis. Direct photolysis and OH reaction also yielded 4-amino-2-hydroxy-6-isopropylamino-1,3,5-triazine (DEAOH) and 6-amino-2-chloro-4-ethylamino-1,3,5-triazine (DIA). Reaction with excited triplet states also produced 2-hydroxy-4,6-diamino-1,3,5-triazine (AN) and 2-chloro-4,6-diamino-1,3,5-triazine (CAAT). Therefore, if biological processes can be neglected and if the low formation yields do not prevent detection, DEAOH and DIA could be used as markers of ATZ direct photolysis and OH reaction, while AN and CAAT could be markers of ATZ reaction with (3)CDOM*. Model predictions concerning ATZ phototransformation were compared with available field data from the literature. When sufficiently detailed field information was provided, good agreement was found with the model. PMID:23972676

Marchetti, Giulia; Minella, Marco; Maurino, Valter; Minero, Claudio; Vione, Davide

2013-08-02

258

The implementation of liquid chromatography tandem mass spectrometry for the official control of lipophilic toxins in seafood: single-laboratory validation under four chromatographic conditions.  

PubMed

We performed a comprehensive study to assess the fit for purpose of four chromatographic conditions for the determination of six groups of marine lipophilic toxins (okadaic acid and dinophysistoxins, pectenotoxins, azaspiracids, yessotoxins, gymnodimine and spirolides) by LC-MS/MS to select the most suitable conditions as stated by the European Union Reference Laboratory for Marine Biotoxins (EURLMB). For every case, the elution gradient has been optimized to achieve a total run-time cycle of 12 min. We performed a single-laboratory validation for the analysis of three relevant matrices for the seafood aquaculture industry (mussels, pacific oysters and clams), and for sea urchins for which no data about lipophilic toxins have been reported before. Moreover, we have compared the method performance under alkaline conditions using two quantification strategies: the external standard calibration (EXS) and the matrix-matched standard calibration (MMS). Alkaline conditions were the only scenario that allowed detection windows with polarity switching in a 3200 QTrap mass spectrometer, thus the analysis of all toxins can be accomplished in a single run, increasing sample throughput. The limits of quantification under alkaline conditions met the validation requirements established by the EURLMB for all toxins and matrices, while the remaining conditions failed in some cases. The accuracy of the method and the matrix effects where generally dependent on the mobile phases and the seafood species. The MMS had a moderate positive impact on method accuracy for crude extracts, but it showed poor trueness for seafood species other than mussels when analyzing hydrolyzed extracts. Alkaline conditions with EXS and recovery correction for OA were selected as the most proper conditions in the context of our laboratory. This comparative study can help other laboratories to choose the best conditions for the implementation of LC-MS/MS according to their own necessities. PMID:23298841

Garca-Altares, M; Diogne, J; de la Iglesia, P

2012-12-19

259

Final Report - Phase II - Biogeochemistry of Uranium Under Reducing and Re-oxidizing Conditions: An Integrated Laboratory and Field Study  

SciTech Connect

Our understanding of subsurface microbiology is hindered by the inaccessibility of this environment, particularly when the hydrogeologic medium is contaminated with toxic substances. Past research in our labs indicated that the composition of the growth medium (e.g., bicarbonate complexation of U(VI)) and the underlying mineral phase (e.g., hematite) significantly affects the rate and extent of U(VI) reduction and immobilization through a variety of effects. Our research was aimed at elucidating those effects to a much greater extent, while exploring the potential for U(IV) reoxidation and subsequent re-mobilization, which also appears to depend on the mineral phases present in the system. The project reported on here was an extension ($20,575) of the prior (much larger) project. This report is focused only on the work completed during the extension period. Further information on the larger impacts of our research, including 28 publications, can be found in the final report for the following projects: 1) Biogeochemistry of Uranium Under Reducing and Re-oxidizing Conditions: An Integrated Laboratory and Field Study Grant # DE-FG03-01ER63270, and 2) Acceptable Endpoints for Metals and Radionuclides: Quantifying the Stability of Uranium and Lead Immobilized Under Sulfate Reducing Conditions Grant # DE-FG03-98ER62630/A001 In this Phase II project, the toxic effects of uranium(VI) were studied using Desulfovibrio desulfuricans G20 in a medium containing bicarbonate or 1, 4-piperazinediethane sulfonic acid disodium salt monohydrate (PIPES) buffer (each at 30 mM, pH 7). The toxicity of uranium(VI) was dependent on the medium buffer and was observed in terms of longer lag times and in some cases, no measurable growth. The minimum inhibiting concentration (MIC) was 140 ?M U(VI) in PIPES buffered medium. This is 36 times lower than previously reported for D. desulfuricans. These results suggest that U(VI) toxicity and the detoxification mechanisms of G20 depend greatly on the chemical forms of U(VI) present and the buffer present in a system. Phase II of this project was supported at a cost of $20,575 with most funds expended to support Rajesh Sani salary and benefits. Results have been published in a peer reviewed journal article.

Brent Peyton; Rajesh Sani

2006-09-28

260

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 g 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 g/ml and 759.71 g/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.

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

2013-01-01

261

Good Practice Recommendations in the Field of Heating, Ventilation, and Air Conditioning for Health Related Research Laboratories.  

ERIC Educational Resources Information Center

A collection of laboratory design notes to set forth minimum criteria required in the design of basic medical research laboratory buildings. Recommendations contained are primarily concerned with features of design which affect quality of performance and future flexibility of facility systems. Subjects of economy and safety are discussed where

Laboratory Design Notes, 1966

1966-01-01

262

Settlement and growth of copper-tolerant Ectocarpus siliculosus (Dillw.) Lyngbye on different copper-based antifouling surfaces under laboratory conditions  

Microsoft Academic Search

The first paper of this series reports the development of an algal culture system suitable for monitoring marine antifouling characteristics of copper-based alloy materials under standardized laboratory conditions, using the marine-fouling algaEctocarpus siliculosus. The physical and chemical conditions necessary for both the formation of corrosion films typical of those formed at sea and vigorous growth of the alga in the

A. Hall; A. J. M. Baker

1985-01-01

263

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

...AIR PROGRAMS (CONTINUED) PROTECTION OF STRATOSPHERIC OZONE Production and Consumption Controls Pt. 82, Subpt...ampoules, marked clearly as substances that deplete the ozone layer, restricted to laboratory use and analytical...

2009-07-01

264

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

...at this time to include equipment calibration; use as extraction solvents, diluents, or carriers for chemical analysis; biochemical research; inert solvents for chemical reactions, as a carrier or laboratory chemical and other critical analytical...

2013-07-01

265

Snap-Frozen Brain Tissue Sections Stored With Desiccant at Ambient Laboratory Conditions Without Chemical Fixation are Resistant to Degradation for a Minimum of 6 Months  

PubMed Central

Cryosectioned tissues from snap-frozen samples offer the advantage of preserving proteins at the cellular and subcellular levels and maintaining overall cell integrity in the tissue of interest without the use of chemical fixatives. To prevent specific or nonspecific degradation of proteins by autolytic and/or proteolytic processes, it is common practice to immediately store frozen tissue sections obtained from a cryostat under cryogenic conditions, for example ?80C. Our laboratory recently challenged this widely held belief by extracting proteins from brain tissue samples that were archived for 1 day, 1 week, 1 month, and 6 months at various storage conditions (frozen, ambient, or desiccated) without the use of chemical fixatives. Our results from immunofluorescent stains, immunoperoxidase stains, silver stains, and Western blot analyses demonstrated that snap-frozen, heat-dried tissue sections stored and desiccated at ambient laboratory conditions are comparable to frozen samples stored up to 6 months.

Sadler, Theodore R.; Khodavirdi, Ani C.; Hinton, David R.; Holschneider, Daniel P.

2009-01-01

266

Minimum leak size determination, under laboratory and commercial conditions, for bacterial entry into polymeric trays used for shelf-stable food packaging.  

PubMed

This study sought to determine the minimum leak size for entry of Enterobacter aerogenes under laboratory conditions, and normal flora under commercial conditions, into tryptic soy broth with yeast extract (TSBYE), homestyle chicken, and beef enchilada packaged in 355-ml polyethylene terephthalate/ethylene vinyl alcohol/polypropylene trays. Channel leaks (diameters of 50 to 200 microm) were made across the sealing area of the trays. Pinholes (diameters of 5 to 50 microm) were made by imbedding laser-drilled metal and plastic disks into the tray lids. For the laboratory simulation, all trays were submerged and agitated for 30 min at 25 degrees C in phosphate-buffered saline that contained 10(7) CFU/ml of E. aerogenes. Under commercial conditions, trays with channel leaks were processed in retorts to achieve commercial sterility. All trays were subsequently incubated at 37 degrees C for 2 weeks, and their contents plated onto eosin-methylene blue agar (for laboratory simulation) to enumerate E. aerogenes and brain heart infusion agar (for commercial conditions) to determine the presence of any bacteria. Under laboratory conditions, minimum pinhole sizes for E. aerogenes entry approximated 5 microm (TSBYE, metal disks; homestyle chicken, plastic disks), 20 microm (beef, plastic disks), and 30 microm (beef, metal disks). The minimum channel leak sizes for entry of E. aerogenes approximated 10 microm (TSBYE), 70 microm (chicken), and 200 microm (beef enchilada). Under commercial conditions, the minimum channel leak size for bacterial entry approximated 40 microm (TSBYE), 50 microm (homestyle chicken), and more than 200 microm (beef). Results showed that E. aerogenes can enter pinholes as small as 5 microm under a worst-case scenario. This information can be used to set pass and fail parameters for leak detection devices. PMID:16300076

Ravishankar, Sadhana; Maks, Nicole D; Teo, Alex Y L; Strassheim, Henry E; Pascall, Melvin A

2005-11-01

267

THE LARVAL STAGES OF THE DEEP SEA RED CRAB, GBRYON QUINQUEDENS SMITH, REARED UNDER LABORATORY CONDITIONS (DECAPODA: BRACHYRHYNCHA)  

Microsoft Academic Search

A prezoeal stage, four zoeal stages, and one megalopa stage WE're obtained from eggs of Geryon quinquedens Smith hatched in the laboratory. Each zoeal stage and the megalopa are discussed and illustrated. The commercial potential and abundance of the deep sea red crab, Geryon quinquedens Smith, are discussed by Schroeder (1959), McRae (1961), and Holmsen (1968). The red crab is

HERBERT C. PERKINS

268

Life cycle, feeding and defecation patterns of Rhodnius ecuadoriensis (Lent & Len 1958) (Hemiptera: Reduviidae: Triatominae) under laboratory conditions  

Microsoft Academic Search

Rhodnius ecuadoriensis is the second most important vector of Chagas Disease (CD) in Ecuador. The objective of this study was to describe (and compare) the life cycle, the feeding and defecation patterns under laboratory con- ditions of two populations of this specie (from the provinces of Manab (Coastal region) and Loja (Andean region)). Egg-to-adult (n = 57) development took an

Anita G Villacs; Laura Arcos-Tern; Mario J Grijalva

2008-01-01

269

An Evaluation of Coded Wire and Elastomer Tag Performance in Juvenile Common Snook under Field and Laboratory Conditions  

Microsoft Academic Search

From 1997 to 2002, retention of coded wire tags (CWTs) and visible implant elastomer (VIE) tags was evaluated in a series of stock enhancement studies with common snook Centropomus undecimalis (60230 mm fork length (FL)). These experiments were conducted in both field and laboratory settings in Sarasota, Florida. Retention rates of CWTs were stable after 30 d and remained greater

Nathan P. Brennan; Kenneth M. Leber; H. Lee Blankenship; John M. Ransier; Roger DeBruler Jr

2005-01-01

270

Carbon dioxide and methane fluxes by a forest soil under laboratory-controlled moisture and temperature conditions  

Microsoft Academic Search

Carbon dioxide and methane are important greenhouse gases whose exchange rates between soils and the atmosphere are controlled strongly by soil temperature and moisture. We made a laboratory investigation to quantify the relative importance of soil moisture and temperature on fluxes of CO2 and CH4 between forest soils and the atmosphere. Forest floor and mineral soil material were collected from

Richard D. Bowden; Kathleen M. Newkirk; Gina M. Rullo

1998-01-01

271

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

272

Life Table for the Tef Grasshopper, Aiolopus longicornis, under Laboratory Conditions and Demographic Effects of the Pathogen Nosema locustae  

Microsoft Academic Search

The tef grasshopper Aiolopus longicornis is a pest of cereals in central Ethiopia. We studied the effects of a biocontrol microorganism, Nosema locustae, on the grasshopper in the laboratory. The demography of a cohort inoculated with N. locustae in the third instar was compared with a noninoculated control cohort. Whereas 55% of the noninoculated grasshoppers reached adulthood, only 19% of

T. Habtewold; J. Landin; U. Wennergen; K. O. Bergman

1995-01-01

273

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

Technology Transfer Automated Retrieval System (TEKTRAN)

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 eff...

274

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.; Kymlinen, H.-R.; Pesonen-Leinonen, E.; Kuisma, R.; Ojala-Paloposki, T.; Hautala, M.; Sjberg, A.-M.

2007-04-01

275

Effectiveness and residual activity comparison of granular formulations of insect growth regulators pyriproxyfen and s-methoprene against Florida mosquitoes in laboratory and outdoor conditions.  

PubMed

Effectiveness and residual activity tests of granular formulations of 2 insect growth regulators (IGRs), s-methoprene and pyriproxyfen, against laboratory-reared larvae of 5 colonized mosquitoes, Aedes aegypti, Aedes albopictus, Aedes taeniorhynchus, Anopheles quadrimaculatus, and Culex nigripalpus, were conducted in the laboratory and outdoors in plastic tubs. Culex quinquefasciatus was exposed to these two IGRs in the laboratory only. Each IGR formulation was applied at 0.02 and 0.05 ppm active ingredient (Al) against 5 of the 6 mosquito species both in the laboratory and the outdoor evaluations, whereas Cx. quinquefasciatus was exposed to 0.2 and 0.4 ppm AI of s-methoprene, and 0.1 and 0.2 ppm AI of pyriproxyfen in the laboratory. s-Methoprene at 0.02 and 0.05 ppm AI resulted in variable levels (<39-100%) of inhibition of adult emergence in the 5 species monitored for 6 weeks after treatment under both test conditions. Aedes taeniorhynchus was the most susceptible to s-methoprene in terms of initial and residual activity. Culex quinquefasciatus and Ae. albopictus were the most tolerant to s-methopene, with maximum emergence inhibitions amounting to 84% in Cx. quinquefasciatus at 0.4 ppm and 44.3% in Ae. albopictus at 0.05 ppm during the 1st week in the laboratory. Pyriproxyfen at comparable treatment rates to s-methoprene caused very high levels (>80-100% in most cases) of initial and residual emergence inhibitions of the tested species in the laboratory as well as outdoors. In several species, pyriproxyfen induced complete inhibition of adult emergence for several weeks after treatment, even at the lower rate of 0.02 ppm. The World Health Organization has recently recommended the use of pyriproxyfen for the control of some mosquito species at specified rates in certain habitats. PMID:12322941

Nayar, Jai K; Ali, Arshad; Zaim, Morteza

2002-09-01

276

Acid and alkaline phosphatase activities and pathological changes induced in Tilapia fish ( Oreochromis sp.) exposed subchronically to microcystins from toxic cyanobacterial blooms under laboratory conditions  

Microsoft Academic Search

The effects of microcystins (MCs) from cyanobacterial cells on the enzymatic activities of acid and alkaline phosphatases (ACP and ALP) from liver, kidney and gill tissues, and the histopathological changes in freshwater Tilapia fish (Oreochromis sp.) were investigated under laboratory conditions. Fish were exposed to cyanobacterial cells (60.0?g MC-LR\\/fish per day) through their diet at different exposure times (14 and

R. Molina; I. Moreno; S. Pichardo; A. Jos; R. Moyano; J. G. Monterde; A. Camen

2005-01-01

277

CO 2 evolution and enzyme activities (dehydrogenase, protease and amylase) of fly ash amended soil in the presence and absence of earthworms ( Drawida willsi Michaelsen) under laboratory conditions  

Microsoft Academic Search

The CO2 evolution and dehydrogenase, protease and amylase activities of fly ash amended soil (Orissa, India) in the presence and absence of earthworms were investigated under laboratory conditions for 2 months at 50% water-holding capacity (WHC) and 252 C temperature. A toxicity test of different age groups (juvenile, immature and adult) of Drawida willsi earthworms, dominant (>80% both in number

Sharada S. Pati; Sanjat K. Sahu

2004-01-01

278

Self Similar Optical Fiber  

NASA Astrophysics Data System (ADS)

This research proposes Self Similar optical fiber (SSF) as a new type of optical fiber. It has a special core that consists of self similar structure. Such a structure is obtained by following the formula for generating iterated function systems (IFS) in Fractal Theory. The resulted SSF can be viewed as a true fractal object in optical fibers. In addition, the method of fabricating SSF makes it possible to generate desired structures exponentially in numbers, whereas it also allows lower scale units in the structure to be reduced in size exponentially. The invention of SSF is expected to greatly ease the production of optical fiber when a large number of small hollow structures are needed in the core of the optical fiber. This dissertation will analyze the core structure of SSF based on fractal theory. Possible properties from the structural characteristics and the corresponding applications are explained. Four SSF samples were obtained through actual fabrication in a laboratory environment. Different from traditional conductive heating fabrication system, I used an in-house designed furnace that incorporated a radiation heating method, and was equipped with automated temperature control system. The obtained samples were examined through spectrum tests. Results from the tests showed that SSF does have the optical property of delivering light in a certain wavelength range. However, SSF as a new type of optical fiber requires a systematic research to find out the theory that explains its structure and the associated optical properties. The fabrication and quality of SSF also needs to be improved for product deployment. As a start of this extensive research, this dissertation work opens the door to a very promising new area in optical fiber research.

Lai, Zheng-Xuan

279

Molluscicidal activities of six species of Bignoniaceae from north-eastern Brazil, as measured against Biomphalaria glabrata under laboratory conditions.  

PubMed

The molluscicidal profile and brine-shrimp bio-activity of the ethanolic extracts of plants from the Bignoniaceae family were determined. The six extracts investigated were of the stems of Melloa quadrivalvis and Tabebuia aurea, and whole plants of Adenocalymma comosum, Arrabidaea parviflora, Cuspidaria argentea and Clytostoma binatum. When tested in the laboratory, with Biomphalaria glabrata as the test snail, all six extracts gave median lethal concentrations (9-54 microg/ml) that fell well below the upper threshold, of 100 mug/ml, set for a potential molluscicide by the World Health Organization. PMID:17524251

Silva, T M S; Da Silva, T G; Martins, R M; Maia, G L A; Cabral, A G S; Camara, C A; Agra, M F; Barbosa-Filho, J M

2007-06-01

280

Diurnal activity rhythms of the subterranean termite Anacanthotermes vagans (Hagen) under laboratory and field conditions of the Kuwait desert  

NASA Astrophysics Data System (ADS)

Daily foraging activity of Anacanthotermes vagans was tested using toilet paper rolls as bait. The highest activity was recorded at midnight and during the hours of the early morning in both summer and winter seasons. In spring the time of highest activity was reversed to take place at midday, afternoon and early evening. Aktograph records in the laboratory demonstrated that individual workers are active most of the day and not naturally entrianed by photoperiods. Daily activity of groups of 10 workers was not statistically different from that of individual workers.

Absuhama, Faysal T.; Al Houty, Wasmia A.

1989-03-01

281

Survival, metabolism and growth of Ulva lactuca under winter conditions: a laboratory study of bottlenecks in the life cycle  

Microsoft Academic Search

Photosynthesis and growth in low light and survival under simulated winter conditions were studied in the freefloating green alga Ulva lactuca L., collected in Roskilde Fjord, Denmark during late autumn and maintained in stock in natural water. It adapts efficiently to low light by increasing chlorophyll concentration and light absorption and continues to grow at the lowest irradiance tested, 0.6

J. E. Vermaat; K. Sand-Jensen

1987-01-01

282

Effects of age and temperature on calling behavior of carob moth, Ectomyelois ceratoniae, zell. (Lepidoptera: Pyralidae) under laboratory conditions.  

PubMed

The sexual calling behaviour of Ectomyelois ceratoniae, (zell.) was observed in the laboratory under 16L: 8D photoperiodic regime and three different constant temperatures, 20, 25 and 30 degrees C. E. ceratoniae, females showed a broad late-scotophase peak of calling activity without any calling throughout the photophase. Most females started calling during the eclosion day on, regardless of the temperature. With increasing age, moths initiated calling significantly earlier at night and the mean time spent calling increased significantly on successive days of calling. There was an inverse relationship between mean time spent calling and mean onset time of calling (r = -0.8079, p < 0.0001) and these parameters significantly affected by age and square of temperature. PMID:19090212

Soofbaf, M; Nouri, G; Goldansaz, S H; Asghari-Zakaria, R

2007-09-01

283

Laboratory-numerical Model Comparisons of Coastal Flows Near Canyons; On The Need To Apply The No-slip Boundary Condition Along Thecoastal Floor  

NASA Astrophysics Data System (ADS)

In a recent paper by Perenne, Haidvogel and Boyer (2001), comparisons of the flow fields obtained by a laboratory and a numerical model for seemingly the same geometrical and dynamical conditions were made. The fluid was linearly stratified and was forced by periodic, along-isobath motion past an idealized canyon incised into a continuous (annular) shelf-shelf break-continental slope bathymetry. The laboratory observations employed particletracking techniques to obtain the horizontal velocity field at selected levels. One of these encompassed the canyon at the shelf break level and was used to compare with simulations obtained from the spectral element ocean model SEOM (Haidvogel and Beckmann, 1999). At the "seafloor", the numerical experiments imposed a simple, linear stress law, i.e., the bottom boundary was partial-slip. In these cases, the horizontal viscosity was taken as 100 times the fluid viscosity to as -sure numerical stability. Comparisons of the time- mean residual flows for the lab and numerical models demonstrated that the numerical predictions were outside the error bars related to laboratory repeatability. A recent calculation which imposes the "correct" (no-slip) bottom boundary condition (but retains the same enhanced viscosity in the hori zontal), and which resolves the resulting no-slip bottom boundary layers, yield considerably improved results for the predicted residual flow field away from the horizontal bounding surfaces. The enhanced horizontal viscosity, however, leads to rather thick layers along the canyon sidewalls which are not observed in the laboratory. The implications for numerical models seem to be that care must be taken to adequately account for the role of these bottom boundary layers, even in si mply forced, laminar situations. A number o f other lab-numerical model comparisons are made, and some energy budgets for control volumes encompassing the canyon are discussed.

Haidvogel, Dale B.; Boyer, Don L.

284

Cymothoa indica (Crustacea, Isopoda, Cymothoidae) parasitizes the cultured larvae of the Asian seabass Lates calcarifer under laboratory conditions.  

PubMed

Parasitic disease in fishes is one of the most important factors limiting aquaculture production and its economic viability. Cymothoa indica, a cymothoid isopod, is reported here for the first time parasitizing cultured larvae of the Asian seabass Lates calcarifer in India. Fourteen-day-old L. calcarifer larvae of mean weight 8.73 +/- 0.03 mg were fed with wild zooplankton in the laboratory. On Day 14 of rearing, larvae were found parasitized by cymothoids. Infected larvae reached a mean (+/- SE) weight of 98.86 +/- 0.30 mg, while uninfected specimens weighed 117 +/- 0.43 mg at the end of the experiment (Day 21). C. indica occurred in the branchial and anterodorsal regions of infected fish, where resultant skin lesions were red, hemorrhagic, without scales and with abundant secreted mucus. The cumulative mortality over the 3 wk period was 16.54 %. These parasites are transferred to the host via the zooplankton used as food; this could easily be overcome, either by filtering wild zooplankton to remove the infectious swimming larvae of C. indica or by using cultured copepods. PMID:16175971

Rajkumar, M; Perumal, P; Trilles, J P

2005-08-01

285

Relative efficacy of repellent-treated wristbands against three major mosquito (Diptera: Culicidae) vectors of disease, under laboratory conditions.  

PubMed

A laboratory study was carried out to evaluate the relative efficacy of N-N-diethyl-m-toluamide (DEET)- and N,N-diethyl phenylacetamide (DEPA)-treated wristbands against three major vector mosquitoes viz., Anopheles stephensi Liston, Culex quinquefasciatus Say and Aedes aegypti (L.), at two different concentrations viz., 1.5 and 2.0 mg/cm(2). Overall, both DEET and DEPA have shown various degrees of repellency impact against all three vector mosquitoes. DEET offered the highest 317.0 min mean complete protection against An. stephensi and DEPA provided 275.6 min complete protection to Cx. quinquefasciatus at 2.0 mg/cm(2). However, DEPA-treated wristbands did not show any significant differences in terms of reduction of human landing rate and mean complete protection time against An. stephensi and Ae. aegypti between 1.5 and 2.0 mg/cm(2). DEET demonstrated relatively higher repellency impact to vector mosquitoes than DEPA. However, ?(2) analysis revealed that there was no statistically significant difference found in repellent efficiency between DEET and DEPA (P = 0.924). The present study result suggests that repellent-treated wristbands could serve as a means of potential personal protection expedient to avoid insect's annoyance and reduce vector-borne disease transmission. They are extremely valuable whenever and wherever other kinds of personal protection measures are unfeasible. PMID:24036563

Karunamoorthi, Kaliyaperumal; Sabesan, Shanmugavelu

2009-12-01

286

Laboratory Measurements of the 5-20 cm Wavelength Opacity of Ammonia Pressure-Broadened by Methane under Jovian Conditions  

NASA Astrophysics Data System (ADS)

In order to fully understand the role methane (CH4) plays in the microwave emission spectra of the deep atmospheres of the outer planets, over 280 laboratory measurements of the opacity of ammonia in a methane environment have been made in the 5-20 cm wavelength range. All opacity measurements were made with either 100 or 200 mbars of ammonia and with 1 to 3 bars of added methane in the 330-450K temperature range. A formalism for the absorptivity of ammonia broadened by methane has now been developed and had been applied to the Hanley et al. (Icarus, v. 202, 2009) model for the opacity of ammonia. Due to methanes relatively low abundance at Jupiter ( 0.2% by volume), its effect on the microwave spectrum which will be observed by the Juno MWR (Microwave Radiometer) will be minimal. However, these experimental results will significantly improve the understanding of the microwave emission spectrum of Uranus and Neptune where methane plays a more dominant role. This work was supported by NASA Contract NNM06AA75C from Marshall Space Flight Center supporting the Juno Mission Science Team, under Subcontract 699054X from the Southwest Research Institute.

Chinsomboon, Garrett; Steffes, P. G.

2012-10-01

287

Effects of work conditions simulated in a laboratory environment and wearer fit on attenuation of slow-recovery foam earplugs  

NASA Astrophysics Data System (ADS)

Laboratory-derived ratings of hearing protector attenuation typically overestimate the protection levels provided in-field. A review of prior research on wearing time effects suggested that attenuation may decrease over time with aural inserts, but that this effect may be device-specific. A psychophysical real-ear measurement procedure was used in an experiment conducted to determine the change in protection levels afforded by particular slow-recovery foam earplugs under different levels of subject fit, subject movement activity and wearing time. Statistical analyses of the spectral attenuation data supported several important results. These compliant inserts were found to be stable in the face of vigorous temporomandibular and highly kinetic bodily activity, thus exhibiting negligible degradation in attenuation over time. However, improvements in attenuation provided by trained-subject fit vs. naive-subject fit of the earplugs were large at 1000 Hz and below, ranging from gains of 12-14 dB, and were smaller, but still statistically significant, at 2000-8000 Hz, ranging from gains of 3-5 dB. Practical implications of the findings are discussed.

Casali, J. G.; Park, M.-Y.

1990-11-01

288

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

289

The influence of rainfall on the coastal slope deformation of the rivers in permafrost conditions (laboratory simulation)  

NASA Astrophysics Data System (ADS)

In the laboratory experiment there were studied the interaction between the river runoff and frozen soil under the change of the thermal (warming) and mechanical (impact of rain) external influences. We studied the time of thawing of soil, infiltration in soil, sediment transport in the channel under the influence of the slope flows, caused by the permafrost thawing and storm flows. The mathematical model for predicting the dynamics of river channels in the permafrost under the influence of external factors was proposed. A system of equations, fully describing the motion of soil on the slopes in permafrost zone, taking into account the intensity of rain in a time-varying ice content of the soil is proposed. It was established experimentally that capacity of the soil is less at a higher initial iciness. As the thawing of the soil capacity is increased, thereby reducing the share of the slope flow. At a constant rate of infiltration ice content and the flow depend only on the intensity of rain. At a low intensity there is no time to saturate the soil and runoff is absent. The experimental data agree well with calculations by the proposed system of equations. This work was supported by RFBR (grants No. 11-05-00393, 11-08-00202).

Gritsuk, I. I.; Debolskaya, E. I.; Maslikova, O. Ja.; Zamjatina, E. V.

2012-04-01

290

Laboratory Growth of Ice Crystals Under Simulated Polar Stratospheric Cloud and High Altitude Cirrus Conditions at Temperatures Below -70 C  

NASA Astrophysics Data System (ADS)

A static diffusion chamber has been used to grow ice crystals at temperatures below -70 C under controlled conditions of temperature, pressure, and ice supersaturation. Type 1 polar stratospheric cloud (PSC) particle growth was performed with frozen nitric acid solution drops in the presence of nitric acid and water vapor at temperatures between -75 C and -85 C. Type 2 PSC particle growth was performed with predominantly pure water at temperatures below -85 C. Ice crystals were also grown from pure water vapor over the same range of temperatures for comparison, nucleating on frozen sulfuric acid solution drops and on mineral dust particles. Linear, projected area, and volume growth rates are presented.

Bailey, M.; Hallett, J.; Peterson, H.; Petersen, D.

2006-12-01

291

Effect of triflumuron, a chitin synthesis inhibitor, on Aedes aegypti, Aedes albopictus and Culex quinquefasciatus under laboratory conditions  

PubMed Central

Background Resistance to traditional insecticides represents a threat to the control of disease vectors. The insect growth regulators (IGR) are a potential alternative to control mosquitoes, including resistant populations. The chitin synthesis inhibitors (CSI) are IGRs, which interfere with the insect molting process and represent one major class of compounds against Aedes aegypti populations resistant to the larvicide organophosphate temephos. In the present study, we evaluated the efficacy of the CSI triflumuron on Culex quinquefasciatus, Aedes albopictus and against several Ae. aegypti field populations. Methods The efficacy of triflumuron, against Cx. quinquefasciatus and Ae. albopictus was evaluated with laboratory strains through doseresponse assays. Additionaly, this CSI was tested against seven Ae. aegypti field populations exhibiting distinct resistance levels to both temephos and the pyrethroid deltamethrin. Aedes aegypti populations were exposed to both a dose that inhibits 99% of the adult emergence of mosquitoes from the susceptible reference strain, Rockefeller, (EI99?=?3.95??g/L) and the diagnostic dose (DD), corresponding to twice the EI99. Results Our results indicate that triflumuron was effective in emergence inhibition (EI) of Cx. quinquefasciatus (EI50= 5.28??g/L; EI90= 12.47??g/L) and Ae. albopictus (EI50= 1.59??g/L; EI90= 2.63??g/L). Triflumuron was also effective against seven Ae. aegypti Brazilian populations resistant to both temephos and deltamethrin. Exposure of all the Ae. aegypti populations to the triflumuron EI99 of the susceptible reference strain, Rockefeller, resulted in complete inhibition of adult emergence, suggesting no cross-resistance among traditional insecticides and this CSI. However, a positive correlation between temephos resistance and tolerance to triflumuron was observed. Conclusion The results suggest that triflumuron represents a potential tool for the control of disease vectors in public health. Nevertheless, they point to the need of constant monitoring of the susceptibility status of vector populations to CSIs.

2013-01-01

292

Mathematical prediction of imidacloprid persistence in two Croatian soils with different texture, organic matter content and acidity under laboratory conditions.  

PubMed

In the present laboratory study, persistence of imidacloprid (IMI) as a function of initial insecticide concentration and soil properties in two Croatian soils (Krk sandy clay and Istria clay soils) was studied and described mathematically. Upon fitting the obtained experimental data for the higher concentration level (5mg/kg) to mathematical models, statistical parameters (R (2), scaled root mean squared error and ? (2) error) indicated that the single first-order kinetics model provided the best prediction of IMI degradation in the Krk sandy clay soil, while in the Istria clay soil biphasic degradation was observed. At the lower concentration level (0.5mg/kg), the biphasic models Gustafson and Holden models as well as the first-order double exponential model fitted the best experimental data in both soils. The disappearance time (DT50) values estimated by the single first-order double exponential model (from 50 to 132days) proved that IMI can be categorized as a moderately persistent pesticide. In the Krk sandy clay soil, resulting DT50 values tended to increase with an increase of initial IMI concentration, while in the Istria clay soil, IMI persistence did not depend on the concentration. Organic matter of both experimental soils provided an accelerating effect on the degradation rate. The logistic model demonstrated that the effect of microbial activity was not the most important parameter for the biodegradation of IMI in the Istria clay soil, where IMI degradation could be dominated by chemical processes, such as chemical hydrolysis. The results pointed that mathematical modeling could be considered as the most convenient tool for predicting IMI persistence and contributes to the establishment of adequate monitoring of IMI residues in contaminated soil. Furthermore, IMI usage should be strictly controlled, especially in soils with low organic matter content where the risk of soil and groundwater contamination is much higher due to its longer persistence and consequent leaching and/or moving from soil surface prior to its degradation. PMID:23998302

Brozni?, Dalibor; Milin, Cedomila

2013-01-01

293

Density gradient quantum similarity  

NASA Astrophysics Data System (ADS)

Computation of density gradient quantum similarity integrals is analyzed, while comparing such integrals with overlap density quantum similarity measures. Gradient quantum similarity corresponds to another kind of numerical similarity assessment between a pair of molecular frames, which contrarily to the usual up to date quantum similarity definitions are not measures, that is: strictly positive definite integrals. As the density gradient quantum similarity integrals are defined as scalar products of three real functions, they appear to possess a richer structure than the corresponding positive definite density overlap quantum similarity measures, while preserving the overall similarity trends, when the molecular frames are relatively moved in three dimensional space. Numerical results within the atomic shell approximation (ASA) framework are presented as simple examples showing the new performances of the gradient density quantum similarity.

Carb-Dorca, Ramon; Mercado, Luz Dary

2012-12-01

294

Olive-oil mill wastewater transport under unsaturated and saturated laboratory conditions using the geoelectrical resistivity tomography method and the FEFLOW model  

NASA Astrophysics Data System (ADS)

An integrated approach for monitoring the vertical transport of a solute into the subsurface by using a geophysical method and a simulation model is proposed and evaluated. A medium-scale (1 m3) laboratory tank experiment was constructed to represent a real subsurface system, where an olive-oil mill wastewater (OOMW) spill might occur. High-resolution cross-hole electrical resistivity tomography (ERT) was performed to monitor the OOMW transport. Time-lapse ERT images defined the spatial geometry of the interface between the contaminated and uncontaminated soil into the unsaturated and saturated zones. Knowing the subsurface characteristics, the finite element flow and transport model FEFLOW was used for simulating the contaminant movement, utilizing the ERT results as a surrogate for concentration measurements for the calibration process. A statistical analysis of the ERT measurements and the corresponding transport model results for various time steps showed a good agreement between them. In addition, a sensitivity analysis of the most important parameters of the simulation model (unsaturated flow, saturated flow and transport) was performed. This laboratory-scale study emphasizes that the combined use of geophysical and transport-modeling approaches can be useful for small-scale field applications where contaminant concentration measurements are scarce, provided that its transferability from laboratory to field conditions is investigated thoroughly.

Seferou, P.; Soupios, P.; Kourgialas, N. N.; Dokou, Z.; Karatzas, G. P.; Candasayar, E.; Papadopoulos, N.; Dimitriou, V.; Sarris, A.; Sauter, M.

2013-09-01

295

Liquid-gas partitioning of the gasoline oxygenate methyl tert-butyl ether (MTBE) under laboratory conditions and its effect on growth of selected algae.  

PubMed

The partitioning of the widely used gasoline additive methyl tert-butyl ether (MTBE) between liquid growth media and gaseous phase was measured daily under laboratory conditions to determine how closely dissolved MTBE concentrations matched nominal concentrations. Total (gaseous and dissolved) MTBE averaged across 6 days for 29.6, 503.2, and 1005.7 mg L-1 MTBE treatments were 89.9, 90.3, and 73.0% of nominal, respectively, and mean dissolved MTBE in these same treatments were 74.6, 73.8, and 69.6% of total MTBE, respectively. This suggests that dissolved MTBE concentrations can vary substantially from nominal. The effect of MTBE on the growth of selected algae was also evaluated under laboratory conditions. Three unicellular algae, Selenastrum capricornutum (Chlorophyta), Navicula pelliculosa (Bacillariophyta), and Synechococcus leopoliensis (= Anacystic nidulans, Cyanophyta = Cyanobacteria), representative of three taxonomic groups, were used as test organisms. Toxicity tests were acute and increase in cell number was used as an indicator of growth. Algal species were exposed by injection of MTBE into sealed vessels containing defined liquid growth media. The growth of N. pelliculosa and S. leopoliensis was negatively affected at nominal 2400 mg L-1 MTBE, whereas the growth of S. capricornutum was negatively affected at nominal 4800 mg L-1 MTBE and positively affected at nominal 600 mg L-1 MTBE. The differential sensitivity of the growth of these representative species suggests that MTBE may alter algal community composition in the natural environment. PMID:9419267

Rousch, J M; Sommerfeld, M R

1998-01-01

296

A simple and inexpensive method for investigating microbiological, enzymatic, or inorganic catalysis using standard histology and microbiology laboratory equipment: assembly, mass transfer properties, hydrodynamic conditions and evaluation.  

PubMed

We introduce a generic, simple, and inexpensive method for performing microbiological, enzymatic, or inorganic catalysis with solids using standard histology and microbiology laboratory equipment. Histology cassettes were used to standardize hydrodynamic conditions and to protect the catalysts and their solid supports. Histology cassettes have the following advantages: they are readily available, inexpensive, solvent and acid resistant, automatable, and the slots in the cassette walls allow liquid to circulate freely. Standard Erlenmeyer flasks were used as reaction vessels. We developed a new camera to observe the movement and position of the histology cassettes as well as the liquid in the Erlenmeyer flasks. The camera produces a stable image of the rotating liquid in the Erlenmeyer flask. This visualization method revealed that in a 250 ml Erlenmeyer flask, stable operating conditions are achieved at a shaking frequency of 300 rpm and a fill volume of 30 ml. In vessels with vertical walls, such as beakers or laboratory bottles, the movement of the histology cassette is not reproducible. Mass transfer characterization using a biological model system and the chemical sulfite-oxidation method revealed that the histology cassette does not influence gas-liquid mass transfer. PMID:17129996

Seletzky, J M; Otten, K; Lotter, S; Fricke, J; Peter, C P; Maier, H R; Bchs, J

297

Considerations in the selection and conditioning of Old World monkeys for laboratory research: animals from domestic sources.  

PubMed

Nonhuman primates from domestic sources constitute an important resource for the research community. The life history of the Old World monkey species that comprise the bulk of this resource is described, and issues that colony managers and researchers alike should consider regarding animal selection (e.g., species, age, sex, rearing history, temperament, genotype, viral status, geographic origin) are discussed. Preparation of domestically bred animals for research usually involves some combination of social separation, relocation, resocialization, alterations in physical space, photoperiod, and diet, as well as exposure to novel environments. The research literature that has focused on these issues is reviewed, and authors suggest that once animals have been assigned to their project housing situation, a period ranging up to 3 mo (depending on the magnitude of the change in housing) might be warranted before an experimental protocol should begin. Attention to issues of animal selection and conditioning by both researchers and colony managers can lead to the shared goal of high-quality research that utilizes the minimal number of animals. PMID:16963810

Capitanio, John P; Kyes, Randall C; Fairbanks, Lynn A

2006-01-01

298

Laboratory Studies of Heterogeneous Reactions of HO2 Radical with Inorganic Aerosol Particles under the Ambient Conditions  

NASA Astrophysics Data System (ADS)

The HO2 uptake coefficient for aerosol particles ((NH4)2SO4 and NaCl) under ambient conditions (760Torr and 296K) was measured using an aerosol flow tube(AFT) coupled with a chemical conversion/laser-induced fluorescence(CC/LIF) technique. The CC/LIF technique enabled experiments to be performed at almost the same HO2 radical concentration as that in the atmosphere(~108 molecules cm-3). HO2 radicals were injected into the AFT through a vertically movable Pyrex tube. Injector position dependent profiles of LIF intensity were measured as a function of aerosol concentration at various relative humilities(RH). The uptake coefficients of dry aerosol (NaCl and (NH4)2SO4) particles were < 0.05, while the uptake coefficients of wet particles of NaCl and (NH4)2SO4 were estimated to be 0.10 and 0.15, respectively, which suggested that heterogeneous loss was enhanced by the particle containing water. To estimate the contribution of heterogeneous loss of HO2 by aerosol, the diurnal variation of HO2 using a box-model calculation was demonstrated. As a result, the daytime maximum concentrations of HO2 were changed to 95 and 70 %, relative to an absence of heterogeneous loss for marine and urban areas, respectively.

Taketani, F.; Kanaya, Y.; Akimoto, H.

2007-12-01

299

Finding similar time series  

Microsoft Academic Search

Similarity of objects is one of the crucial concepts in several applications, including data mining. For complex objects, similarity is nontrivial to define. In this paper we present an intuitive model for measuring the similarity between two time series. The model takes into account outliers, different scaling functions, and variable sampling rates. Using methods from computational geometry, we show that

Gautam Das; Dimitrios Gunopulos; Heikki Mannila

300

The Gender Similarities Hypothesis  

Microsoft Academic Search

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 support the gender similarities hypothesis. Gender differences can vary

Janet Shibley Hyde

2005-01-01

301

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

302

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

303

Practice with Similarity Proofs  

NSDL National Science Digital Library

In this worksheet of eight questions, students practice their knowledge of similarity proofs. In the first four questions, students determine which postulate or theorem works to prove triangle similarity - AA, SAS, or SSS. In the last four questions, students are asked to work through the proof of various problems. The answers are embedded in the page, and this is a helpful resource for students to work with similarity proofs.

Roberts, Donna

2000-01-01

304

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

305

Assessing similarity between profiles  

Microsoft Academic Search

General methodological difficulties are discussed, particularly; the need to discuss similarity only with respect to specified dimensions, loss of information involved when configurations are reduced to indices, the need to interpret a similarity index as a relative rather than as an absolute measure, and the general non-comparability of scale units involved in profiles. The measure D is presented. This is,

Lee J. Cronbach; Goldine C. Gleser

1953-01-01

306

Measures of catchment similarity  

NASA Astrophysics Data System (ADS)

Similarity of catchments is often defined on the basis of discharge series. Similarity measures are formulated using dependence measures (such as correlation or empirical copula based variables) relating these series. A major drawback of these approaches is that they can only detect similarity for catchments with the same weather. Further as weather of different time periods is different one would consider the same catchment as dissimilar to itself. The goal of this contribution is to introduce different similarity measures which reflect functional similarity (transformation of precipitation to discharge) and filter out the effects of weather. The alternative similarity measures are defined using: Flow duration curves Recession curve behaviour Bivariate copulas between antecedent precipitation and discharge Boundary curves of the response dynamics These measures enable the calculation of the self similarity of catchments, providing them reasonable limits and an objective evaluation. The methodology is applied to a large set of US catchments. The usefulness of the similarity measures is tested for the hydrological model HYMOD.

Brdossy, A.; Huang, Y.; Wagener, T.

2012-04-01

307

Assessing the impact of land-applied biosolids from a thermomechanical (TMP) pulp mill to a suite of terrestrial and aquatic bioassay organisms under laboratory conditions.  

PubMed

The potential impact on a variety of bioassay organisms when pulp-mill biosolids from a thermomechanical pulp mill (western Canada) were applied to a reference soil has been investigated in a laboratory setup. The current research assessed acute, chronic, and reproductive impacts using a battery of terrestrial and aquatic organisms. Terrestrial organisms were exposed to soil amended with different concentrations of biosolids, while aquatic organisms were used to assess the impact of biosolids' runoff into receiving waters. The former bioassays showed that an application rate of 20 tonneshectare(-1) (tha(-1)) "bone-dry" biosolids applied to reference soil produced no observable adverse impact on the terrestrial organisms. In the latter assays, undiluted (100%) and 50% diluted biosolids' runoff into receiving water had a detrimental impact on the aquatic organisms. However, concentrations not exceeding 25% (environmentally relevant concentrations) had neither an acute nor chronic impact compared to reference populations. The organisms' abilities to reproduce were also unaltered. While this study only examined the biosolids from one mill, there is the potential that land-application of characteristically well-defined pulp mill biosolids may constitute an acceptable way of disposing of pulp and paper mill biosolid residues. However, the biosolids coming from different mills, with differing processes, must be dealt with on a case-by-case situation. Each series of biosolids must be rigorously tested for toxicological impact in the laboratory under tightly controlled conditions. Subsequently, field experimentation must be conducted before definitive conclusions can be made. PMID:15681182

Bostan, Vadim; McCarthy, Lynda H; Liss, Steven N

2005-01-01

308

Effect of six non-target snails on Schistosoma mansoni miracidial host finding and infection of Biomphalaria alexandrina under laboratory conditions.  

PubMed

Six snail species naturally associated with Biomphalaria alexandrina, the snail host of Schistosoma mansoni in Egypt, were tested under standard laboratory conditions, for impact on miracidial host findings and infection of the snail host. These snails are the prosobranchs Melanoides tuberculata, Cleopatra bulimoides, Bellamys unicolor and Lanistes carinatus, the pulmonates Planorbis planorbis and Physa acuta. The tested snail ssp. reduced considerably the infection rate of Biomphalaria with S. mansoni especially at a ratio of 10 decoy snails to one Biomphalaria snail. The prosobranchs Melanoides, Cleopatra and Lanistes exhibited more reducing effect on Biomphalaria infection than Bellamya and the pulmonates Physa and Planorbis being 65.2%, 78.8%, 62.9%, 33.3%, 30.3% and 46.9%, respectively. PMID:9707684

Yousif, F; el-Emam, M; el-Sayed, K

1998-08-01

309

Models for the Centimeter-Wavelength Opacity of Sulfur Dioxide and Carbon Dioxide based on Laboratory Measurements Conducted under Simulated Conditions for the Deep Atmosphere of Venus  

NASA Astrophysics Data System (ADS)

In the past two decades, multiple observations of Venus have been made at X band (3.6 cm) using the Jansky Very Large Array (VLA), and maps have been created of the 3.6 cm emission from Venus. Since the emission morphology is related both to surface features and to deep atmospheric absorption from CO2 and SO2 (see, e.g., Butler et al., Icarus 154, 2001), knowledge of the microwave absorption properties of sulfur dioxide in a carbon dioxide atmosphere under conditions for the deep atmosphere of Venus is required for proper interpretation. Initial measurements of the centimeter-wavelength (3.7-20 cm) of SO2 and CO2 under simulated conditions for the deep atmosphere of Venus, conducted using a new high-pressure system operating at 430 K and at pressures up to 92 Bars, were presented by Steffes and Barisich (DPS-2012, B.A.A.S., v.44, p.241). Over the past year, we have completed this measurement campaign for temperatures up to 550 K, so as to better understand the effects of SO2 and CO2 on the microwave emission from the Venus boundary layer. Results indicate that the model for the centimeter-wavelength opacity from pure CO2 (developed over 40 years ago -- Ho et al., JGR 71, 1966), is valid over the entire centimeter-wavelength range under simulated conditions for the deep atmosphere of Venus. Additionally, the laboratory results indicate that the model for the centimeter-wavelength opacity of SO2 in a CO2 atmosphere from Suleiman et al. (JGR-Planets, 101, Feb. 1996) can reliably be used under conditions of the deep atmosphere of Venus with the modifications described in this paper . This work is supported by the NASA Planetary Atmospheres Program under Grant NNX11AD66G.

Steffes, Paul G.; Shahan, P. M.

2013-10-01

310

The gender similarities hypothesis.  

PubMed

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 support the gender similarities hypothesis. Gender differences can vary substantially in magnitude at different ages and depend on the context in which measurement occurs. Overinflated claims of gender differences carry substantial costs in areas such as the workplace and relationships. PMID:16173891

Hyde, Janet Shibley

2005-09-01

311

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

312

Approaching Mars-like Geochemical Conditions in the Laboratory: Omission of Artificial Buffers and Reductants in a Study of Biogenic Methane Production on a Smectite Clay  

NASA Astrophysics Data System (ADS)

Methanogens have not been shown to metabolize in conditions exactly analogous to those present in Mars' subsurface. In typical studies of methanogenic metabolism, nutrient-rich buffered media and reducing agents are added to the cultures in an attempt to optimize the environment for methanogen survival and growth. To study methanogens in more Mars-relevant laboratory conditions, efforts should be made to eliminate artificial media, buffers, and reducing agents from investigations of methanogenic metabolism. After preliminary work to compare methanogen viability on montmorillonite clay and JSC Mars-1 regolith simulant, a study was conducted to determine whether biological methanogenesis could occur in non-reduced, non-buffered environments containing only H2, CO2, montmorillonite, and the liquid fraction extracted from a montmorillonite/deionized water suspension. Biogenic methane was observed in the microenvironments despite the omission of traditional media, buffers, and reducing agents. Mean headspace methane concentration after 96 days of observation was 10.23 0.64% (% vol SEM, n = 4). However, methane production was severely decreased with respect to reduced, buffered microenvironments (Day 28: 31.98% 0.19%, n = 3). Analysis of results and comparison to previous work indicate that montmorillonite clay has a strong ability to supply micronutrients necessary for methanogenic metabolism, and the liquid fraction from a montmorillonite/deionized water slurry can successfully be used as an alternative to reduced and buffered nutritive media in Mars-relevant studies of methanogenic metabolism.

Chastain, Brendon K.; Kral, Timothy A.

2010-11-01

313

Self-Similar Lattice Tilings  

Microsoft Academic Search

We study the general question of the existence of self-similar lattice tilings of Euclidean space. A necessary and sufficient\\u000a geometric condition on the growth of the boundary of approximate tiles is reduced to a problem in Fourier analysis that is\\u000a shown to have an elegant simple solution in dimension one. In dimension two we further prove the existence of connected

Karlheinz Grochenig; Andrew Haas

1994-01-01

314

Effect of wind speed on the pheromone-mediated behavior of sexual morphs of the potato aphid, Macrosiphum euphorbiae (Thomas) under laboratory and field conditions.  

PubMed

The effect of wind on the potato aphid, Macrosiphum euphorbiae, male responsiveness to the sex pheromone, and on the calling behavior of virgin oviparae, was studied under constant wind speeds in the laboratory and in the field. A significant proportion of females called at wind speeds up to 4 m/sec, whereas male flight behavior in clean air was inhibited at velocities > 2 m/sec. However, males continued to walk over the range of wind speeds at which females called. Under constant wind velocities in a wind tunnel, males downwind of calling females oriented on the upwind edge of the release stand, and fewer individuals took flight at low constant wind speeds than in a clean air plume. In all cases, whether calling females were present or not, the males that took flight moved downwind. However, when a bridge was available, a significant proportion of males walked upwind to the pheromone source. The same orientation and walking behaviors were observed when males were placed downwind of calling females under variable wind conditions in the field. However, contrary to the laboratory results, 30% of the males tested flew upwind and landed on the source. A more detailed examination found that males orienting toward a source would walk if wind speeds were high but initiated flight in an "upwind" direction if there was a lull in wind velocity. These findings suggest that for the potato aphid, and probably for many other insect species with weak flight capacity, walking behavior is a significant component of pheromone-mediated mate location. This would permit males to continue foraging for calling females in the vicinity when wind velocities inhibit flight. PMID:16900427

Goldansaz, Seyed H; McNeil, Jeremy N

2006-08-02

315

Good Laboratory Practices for Molecular Genetic Testing for Heritable Diseases and Conditions. Morbidity and Mortality Weekly Report, Vol. 58, No. RR-6, June 12, 2009.  

National Technical Information Service (NTIS)

Under the Clinical Laboratory Improvement Amendments of 1988 (CLIA) regulations, laboratory testing is categorized as waived (from routine regulatory oversight) or nonwaived based on the complexity of the tests; tests of moderate and high complexity are n...

2009-01-01

316

Discovering Similar Multidimensional Trajectories  

Microsoft Academic Search

We investigate techniques for analysis and retrieval of object trajectories in a two or three dimensional space. Such kind of data usually contain a great amount of noise, that makes all previously used metrics fail. Therefore, here we formalize non-metric similarity functions based on the Longest Common Subsequence (LCSS), which are very ro- bust to noise and furthermore provide an

Michail Vlachos; Dimitrios Gunopulos; George Kollios

2002-01-01

317

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. Vitnyi

2007-01-01

318

The Qualitative Similarity Hypothesis  

ERIC Educational Resources Information Center

|Evidence is presented for the qualitative similarity hypothesis (QSH) with respect to children and adolescents who are d/Deaf or hard of hearing. The primary focus is on the development of English language and literacy skills, and some information is provided on the acquisition of English as a second language. The QSH is briefly discussed within

Paul, Peter V.; Lee, Chongmin

2010-01-01

319

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

320

Examination of the structure and evolution of ion energy properties of a 5 kW class laboratory Hall effect thruster at various operational conditions  

NASA Astrophysics Data System (ADS)

This thesis represents an effort to design, build, and characterize a 5 kW class Hall thruster for laboratory work. Particular attention was paid to plume because they cause interaction issues for satellite manufacturers and users due to their potential for damaging spacecraft surfaces and interfering with operations. A brief discussion of the history and physics of electric propulsion is provided, with more detail given for Hall thrusters. A procedure for Hall thruster design was developed based on Russian design equations and a parameter study of existing commercial thrusters. This method was used to design the University of Michigan/United States Air Force P5 5 kW class laboratory Hall thruster. This thruster was designed for easy diagnostic access and modification. Performance measurements of the P5 indicated that it operated on par with commercial thrusters. To further characterize and analyze the ion acceleration structure of the P5, an extensive study of ion energy distributions and ionic species composition was made using the Molecular Beam Mass Spectrometer, a time-of- flight mass spectrometer with a 45-degree electrostatic energy analyzer. Measurements were taken at various angles with respect to the thruster at two axial locations in order to gain insight into the acceleration structure and how it is affected by the Hall thruster's annular configuration. These measurements were performed at several operating conditions to investigate how changes to the discharge voltage and current affected the acceleration structure. The effects of the facility on the data were also investigated. Ion energy distribution measurements indicated an overall inward focus to the plume of the P5, with many ions accelerated from the annular discharge chamber across thruster centerline. This structure was consistent at all operating conditions. Time of flight measurements indicated that the plume was composed primarily of singly ionized xenon, with detectable fractions of doubly, triply, and quadruply ionized xenon. It was found that by sampling the plasma in the near field, the effects of interactions with background neutral xenon could be minimized. Comparisons of the results with those obtained using laser induced fluorescence indicate agreement once the proper transformation of parameters is employed.

Gulczinski, Frank Stanley, III

1999-12-01

321

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

322

Search for seasonal rhythmicity of pineal melatonin production in rats under constant laboratory conditions: spectral chronobiological analysis, and relation to solar and geomagnetic variables.  

PubMed

Earlier we reported that in a number of experiments pineal melatonin production in rats under constant laboratory conditions displayed seasonal rhythms but subsequently were not always able to confirm this. Since there was no indication under which conditions such rhythms may be present, we performed four consecutive identical experiments with untreated female Sprague-Dawley rats within the same animal room during 1997-2006. Nocturnal urine samples (19-23, 23-3, 3-7 h) were collected at monthly intervals over 494-658 d with 12 animals each in experiments I and II (1997-1999, 1999-2000), 30 animals in experiment III (2002-2004), and 15 in experiment IV (2005-2006). 6-Sulfatoxymelatonin (aMT6s) was measured by ELISA. The excreted aMT6s at each time interval as well as total nocturnal aMT6s-excretion (19-7 h) was submitted to standard statistical analyses as well as to a spectral chronobiological analysis to determine the period lengths of the components involved which was followed by processing with the single cosinor method. Seasonal rhythm components (circannual period length: 360 60 d) were detected in experiment III (2002-2004) for the overall nocturnal excretion as well as for two sub-intervals (23-3 and 3-7 h) and in one night interval of experiment II (23-3 h). Multiple components with mostly short period lengths of around 100 d and some long ones of 500-650 d were found in the other experiments. Systematic MESOR and amplitude variations were observed during the experiments, being highest in experiment II (19-7 h, also 23-3 h and 3-7 h) and lowest in experiments I and IV. These results illustrate that seasonal melatonin rhythms are not a general phenomenon in female laboratory rats indicating an involvement of unknown environmental cues. As an extension of our earlier hypothesis regarding a seasonal Zeitgeber function of the horizontal intensity H of the geomagnetic field showing circannual variations, we assume further modulation by the 11-yrs' sunspot cycle which leads to geomagnetic disturbances and could facilitate seasonal aMT6s rhythmicity during specific years. PMID:22971170

Bartsch, Hella; Mecke, Dieter; Probst, Hansgeorg; Kpper, Heinz; Seebald, Eckard; Salewski, Lothar; Stehle, Thilo; Bartsch, Christian

2012-10-01

323

Larval food quantity affects development time, survival and adult biological traits that influence the vectorial capacity of Anopheles darlingi under laboratory conditions  

PubMed Central

Background The incidence of malaria in the Amazon is seasonal and mosquito vectorial capacity parameters, including abundance and longevity, depend on quantitative and qualitative aspects of the larval diet. Anopheles darlingi is a major malaria vector in the Amazon, representing >95% of total Anopheles population present in the Porto Velho region. Despite its importance in the transmission of the Plasmodium parasite, knowledge of the larval biology and ecology is limited. Studies regarding aspects of adult population ecology are more common than studies on larval ecology. However, in order develop effective control strategies and laboratory breeding conditions for this species, more data on the factors affecting vector biology is needed. The aim of the present study is to assess the effects of larval food quantity on the vectorial capacity of An. darling under laboratory conditions. Methods Anopheles darlingi was maintained at 28C, 80% humidity and exposed to a daily photoperiod of 12?h. Larvae were divided into three experimental groups that were fed either a low, medium, or high food supply (based on the food amounts consumed by other species of culicids). Each experiment was replicated for six times. A cohort of adults were also exposed to each type of diet and assessed for several biological characteristics (e.g. longevity, bite frequency and survivorship), which were used to estimate the vectorial capacity of each experimental group. Results The group supplied with higher food amounts observed a reduction in development time while larval survival increased. In addition to enhanced longevity, increasing larval food quantity was positively correlated with increasing frequency of bites, longer blood meal duration and wing length, resulting in greater vectorial capacity. However, females had greater longevity than males despite having smaller wings. Conclusions Overall, several larval and adult biological traits were significantly affected by larval food availability. Greater larval food supply led to enhance larval and production and larger mosquitoes with longer longevity and higher biting frequency. Thus, larval food availability can alter important biological traits that influence the vectorial capacity of An. darlingi.

2012-01-01

324

Similarity and denoising.  

PubMed

We can discover the effective similarity among pairs of finite objects and denoise a finite object using the Kolmogorov complexity of these objects. The drawback is that the Kolmogorov complexity is not computable. If we approximate it, using a good real-world compressor, then it turns out that on natural data the processes give adequate results in practice. The methodology is parameter-free, alignment-free and works on individual data. We illustrate both methods with examples. PMID:23277611

Vitnyi, Paul M B

2012-12-31

325

Indexing Similar DNA Sequences  

NASA Astrophysics Data System (ADS)

To study the genetic variations of a species, one basic operation is to search for occurrences of patterns in a large number of very similar genomic sequences. To build an indexing data structure on the concatenation of all sequences may require a lot of memory. In this paper, we propose a new scheme to index highly similar sequences by taking advantage of the similarity among the sequences. To store r sequences with k common segments, our index requires only O(n + NlogN) bits of memory, where n is the total length of the common segments and N is the total length of the distinct regions in all texts. The total length of all sequences is rn + N, and any scheme to store these sequences requires ?(n + N) bits. Searching for a pattern P of length m takes O(m + m logN + m log(rk)psc(P) + occlogn), where psc(P) is the number of prefixes of P that appear as a suffix of some common segments and occ is the number of occurrences of P in all sequences. In practice, rk ? N, and psc(P) is usually a small constant. We have implemented our solution and evaluated our solution using real DNA sequences. The experiments show that the memory requirement of our solution is much less than that required by BWT built on the concatenation of all sequences. When compared to the other existing solution (RLCSA), we use less memory with faster searching time.

Huang, Songbo; Lam, T. W.; Sung, W. K.; Tam, S. L.; Yiu, S. M.

326

Complete larval development of the hermit crabs Clibanarius aequabilis and Clibanarius erythropus (Decapoda: Anomura: Diogenidae), under laboratory conditions, with a revision of the larval features of genus Clibanarius  

NASA Astrophysics Data System (ADS)

The complete larval development (four zoeae and one megalopa) of Clibanarius aequabilis and C. erythropus, reared under laboratory conditions, is described and illustrated. The larval stages of the two northeastern Atlantic Clibanarius species cannot be easily differentiated. Their morphological characters are compared with those of other known Clibanarius larvae. The genus Clibanarius is very homogeneous with respect to larval characters. All Clibanarius zoeae display a broad and blunt rostrum, smooth abdominal segments and an antennal scale without a terminal spine. Beyond the second zoeal stage, the fourth telson process is present as a fused spine, and the uropods are biramous. In the fourth larval stage all species display a mandibular palp. The Clibanarius megalopa presents weakly developed or no ocular scales, symmetrical chelipeds, apically curved corneous dactylus in the second and third pereiopods, and 5-11 setae on the posterior margin of the telson. Apart from the number of zoeal stages, Clibanarius species may be separated, beyond the second zoeal stage, by the telson formula and the morphology of the fourth telson process.

Bartilotti, Ctia; Calado, Ricardo; Dos Santos, Antonina

2008-06-01

327

Optimization of detection conditions and single-laboratory validation of a multiresidue method for the determination of 135 pesticides and 25 organic pollutants in grapes and wine by gas chromatography time-of-flight mass spectrometry.  

PubMed

This paper describes single-laboratory validation of a multiresidue method for the determination of 135 pesticides, 12 dioxin-like polychlorinated biphenyls, 12 polyaromatic hydrocarbons, and bisphenol A in grapes and wine by GC/time-of-flight MS in a total run time of 48 min. The method is based on extraction with ethyl acetate in a sample-to-solvent ratio of 1:1, followed by selective dispersive SPE cleanup for grapes and wine. The GC/MS conditions were optimized for the chromatographic separation and to achieve highest S/N for all 160 target analytes, including the temperature-sensitive compounds, like captan and captafol, that are prone to degradation during analysis. An average recovery of 80-120% with RSD < 10% could be attained for all analytes except 17, for which the average recoveries were 70-80%. LOQ ranged within 10-50 ng/g, with < 25% expanded uncertainties, for 155 compounds in grapes and 151 in wine. In the incurred grape and wine samples, the residues of buprofezin, chlorpyriphos, metalaxyl, and myclobutanil were detected, with an RSD of < 5% (n = 6); the results were statistically similar to previously reported validated methods. PMID:21391504

Dasgupta, Soma; Banerjee, Kaushik; Dhumal, Kondiba N; Adsule, Pandurang G

328

Similarity of Mold Metallurgy  

NASA Astrophysics Data System (ADS)

The governing equations for hydrodynamics and electromagnetism can be described by a general differential equation, which involves, in convective terms, diffusion and source. The finite-volume method, which has been widely applied in the field of computational fluid dynamics, is introduced to solve the magnetohydrodynamics equations. Numerical results show that the spatial distribution of flow field, temperature field, inclusion concentration field, and inclusion number density field are similar. All of them have the upper and lower recirculation region. But the electromagnetic field follows another rule: the symmetric static magnetic field and the symmetric flow field produce the asymmetric induced current density field and the symmetric electromagnetic force.

Lei, Hong

2012-09-01

329

Visual similarity effects in categorical search.  

PubMed

We asked how visual similarity relationships affect search guidance to categorically defined targets (no visual preview). Experiment 1 used a web-based task to collect visual similarity rankings between two target categories, teddy bears and butterflies, and random-category objects, from which we created search displays in Experiment 2 having either high-similarity distractors, low-similarity distractors, or "mixed" displays with high-, medium-, and low-similarity distractors. Analysis of target-absent trials revealed faster manual responses and fewer fixated distractors on low-similarity displays compared to high-similarity displays. On mixed displays, first fixations were more frequent on high-similarity distractors (bear = 49%; butterfly = 58%) than on low-similarity distractors (bear = 9%; butterfly = 12%). Experiment 3 used the same high/low/mixed conditions, but now these conditions were created using similarity estimates from a computer vision model that ranked objects in terms of color, texture, and shape similarity. The same patterns were found, suggesting that categorical search can indeed be guided by purely visual similarity. Experiment 4 compared cases where the model and human rankings differed and when they agreed. We found that similarity effects were best predicted by cases where the two sets of rankings agreed, suggesting that both human visual similarity rankings and the computer vision model captured features important for guiding search to categorical targets. PMID:21757505

Alexander, Robert G; Zelinsky, Gregory J

2011-07-14

330

Extended Self Similarity in Solar Wind Turbulence  

NASA Astrophysics Data System (ADS)

The solar wind provides a natural laboratory for observations of MHD turbulence over extended temporal scales. A hallmark of turbulence is scaling- and scaling in the Probability Density Functions (PDF) of fluctuations in certain solar wind in- situ bulk plasma parameters has been established from WIND and ACE observations on `short' timescales up to a few hours. On longer timescales there is a crossover in scaling to uncorrelated behaviour. The intermittency of the system is expressed in these parameters through the non-Gaussian nature of the fluctuations PDF up to this timescale. Here we apply a generic approach to turbulence- that of Extended Self Similarity (ESS)- to the analysis of solar wind observations. We find that ESS can extend the range of scaling and for some parameters reveals two distinct scaling regions for the `short' and long timescales, whereas for others, a single scaling encompasses the behaviour over the full range of timescales. That certain parameters, and conditions, can be distinguished via ESS may provide physical insight into the turbulent solar wind.

Rowlands, G.; Chapman, S. C.; Hnat, B.

2005-12-01

331

Potential for Occupational Exposure to Engineered Carbon-Based Nanomaterials in Environmental Laboratory Studies.  

National Technical Information Service (NTIS)

Background: The potential exists for laboratory personnel to be exposed to engineered carbonaceous nanomaterials (CNMs) in studies aimed at producing conditions similar to those found in natural surface waters (e.g., presence of natural organic matter (NO...

A. J. Kennedy D. R. Johnson J. A. Steevens M. M. Methner

2009-01-01

332

Update of Hydrologic Conditions and Distribution of Selected Constituents in Water, Snake River Plain Aquifer and Perched-Water Zones, Idaho National Laboratory, Idaho, Emphasis 2002-05.  

National Technical Information Service (NTIS)

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds, evaporation ponds, and disposal wells at the Idaho National Laboratory (INL) has affected water quality in the Snake River Plain aquifer and perched-water zones underlying ...

L. C. Davis

2008-01-01

333

Laboratory Research for Desulfurizing and No-Reduction by Addition of Ammonia under the Conditions of the Bergbau-Forschung Flue Gas Desulfurizing Process.  

National Technical Information Service (NTIS)

Laboratory tests were conducted for improving the catalytic efficiency of charcoal and for improving the thermal regeneration of the activated carbon. The injection of ammonia enhances SO2 removal. At high SO2 concentrations, the reduction of NO component...

E. Richter H. J. Schmidt J. Jung

1982-01-01

334

Similarity, interactive activation, and mapping  

Microsoft Academic Search

Abstract: IntroductionHuman assessments of similarity are fundamental to cognition because similarities in theworld are revealing. The world is an orderly enough place that similar objects and events tendto behave similarly. This fact of the world is not just a fortunate coincidence. It is becauseobjects are similar that they will tend to behave similarly in most respects. It is becausecrocodiles and

Robert L. Goldstone

1994-01-01

335

Effect of Azadirachta indica (neem), sodium thiosulphate and calcium chloride on changes in nitrogen transformations and inhibition of nitrification in soil incubated under laboratory conditions.  

PubMed

A laboratory experiment was conducted to examine the effects of nitrification inhibitors (NIs) neem seed-cake (Azadirachta indica) (NSC), sodium thiosulphate (Na?S?O?) and calcium chloride (CaCl?) on changes in NH?(+)?N, inhibition of nitrification and recovery of applied nitrogen (N) in soil. Surface soil samples of 0-15 cm were collected from an arable field, amended with urea N (UN) at the rate 200 mg N kg?, UN+NSC, UN+Na?S?O? and UN+CaCl? and incubated at 22C periodically over 50 d. Soil without any amendment was used as check (control). Results indicated that more than 58% of N applied as NH?? disappeared over a period of 50 d from the soil mineral-N pool. Some of this N (21%) was accumulated as NO??-N while the remaining N was unaccounted for. Addition of nitrification inhibitors NSC, Na?S?O?, and CaCl? resulted in a decrease in the extent of NH?(+) disappearance by 35%, 44% and 30%, respectively. In the treatment receiving UN alone, 56 mg NO??-N kg? was accumulated over 50 d (maximum 93 mg kg?) indicated an active nitrification. Application of nitrification inhibitors NSC, Na?S?O?, and CaCl? with UN inhibited nitrification by 54%, 64%, and 59%, respectively. Apparent N recovery (ANR) in the treatment receiving UN alone was 63% that substantially increased to 83%, 89% and 76% in the treatments receiving UN+NSC, UN+Na?S?O?, and UN+CaCl?, respectively indicating 32%, 41% and 20% increase in N recovery. Among three NIs tested, Na?S?O? proved superior in inhibiting nitrification and increasing ANR. The study demonstrated that application of NSC, Na?S?O?, and CaCl? which are cheap and easily available NIs inhibited nitrification and improved N recovery efficiency of applied N in an arable soil very effectively. It is suggested that these inhibitors should be tested under field conditions for increasing NUE and improving crop productivity. PMID:21146192

Abbasi, M Kaleem; Hina, Munazza; Tahir, Majid Mahmood

2010-12-13

336

Taxonomy Learning using Term Specificity and Similarity  

Microsoft Academic Search

Learning taxonomy for technical terms is difficult and tedious task, especially when new terms should be included. The goal of this paper is to assign taxonomic relations among technical terms. We pro- pose new approach to the problem that relies on term specificity and similarity measures. Term specificity and similarity are necessary conditions for taxonomy learning, because highly specific terms

Pum-Mo Ryu; Key-Sun Choi

2006-01-01

337

A Scale of Bidirectional Similarity.  

National Technical Information Service (NTIS)

Sets of ambiguous stimuli built around reversible figures were constructed, scaled, and validated. Positions on a continuum of bidirectional similarity were determined in terms of per cent similarity to each of two referent prototypes, similarity being de...

J. H. Brown

1964-01-01

338

Effect of Wind Speed on the Pheromone-Mediated Behavior of Sexual Morphs of the Potato Aphid, Macrosiphum euphorbiae (Thomas) Under Laboratory and Field Conditions  

Microsoft Academic Search

The effect of wind on the potato aphid, Macrosiphum euphorbiae, male responsiveness to the sex pheromone, and on the calling behavior of virgin oviparae, was studied under constant wind speeds in the laboratory and in the field. A significant proportion of females called at wind speeds up to 4m\\/sec, whereas male flight behavior in clean air was inhibited at velocities

Seyed H. Goldansaz; Jeremy N. McNeil

2006-01-01

339

The effect of four fruit species on the parasitization rate of Anastrepha fraterculus (Diptera: Tephritidae, Trypetinae) by Diachasmimorpha longicaudata (Hymenoptera: Braconidae, Opiinae) under laboratory rearing conditions  

Microsoft Academic Search

In the laboratory, the effect of host fruit species Citrus paradisi, C. aurantium, Prunus persica, and Psidium guajava on A. fraterculus parasitism by Diachasmimorpha longicaudata was studied. The number of ovipositor-probing events and the probing-time were documented to evaluate the role of fruit chemistry, and epicarp and mesocarp thickness, respectively. The relationship between the parasitization rate and fruit size in

Sergio M. Ovruski; Luis E. Oroo; Pablo Schliserman; Segundo Nuez-Campero

2007-01-01

340

New High-Precision Laboratory Measurements of the Hydrogen and Helium Broadened Microwave Opacity of Ammonia under Simulated Deeper Atmospheric Jovian Conditions  

Microsoft Academic Search

New laboratory measurements of the microwave opacity of ammonia in a hydrogen\\/helium atmosphere up to pressures of 12 bars have been performed using the high-precision microwave measurement system developed at Georgia Tech. These measurements have an increased accuracy and reliability over all previous measurements due to new procedures to combat the uncertainty from ammonia adsorption in the test chambers combined

Thomas R. Hanley; P. G. Steffes

2007-01-01

341

Lethal and sublethal effects of endosulfan, imidacloprid and indoxacarb on first instar larvae of Chrysoperla carnea (Neu.: Chrysopidae) under laboratory conditions  

Microsoft Academic Search

The common green lacewing is an important natural enemy used for pest control in greenhouses. It is also very common in many agricultural systems. Hence, studying lethal and sublethal effects of insecticides on this predator would be useful. Toxicity of endosulfan, imidacloprid and indoxacarb was assessed on 1 st instar larvae of Chrysoperla carnea (Stephens) in laboratory. Residual bioassays were

M. Hejazi; S. A. Mohammadi

342

Beyond topical similarity: a structural similarity measure for retrieving highly similar documents  

Microsoft Academic Search

Accurately measuring document similarity is important for many text applications, e.g. document similarity search, document\\u000a recommendation, etc. Most traditional similarity measures are based only on bag of words of documents and can well evaluate\\u000a document topical similarity. In this paper, we propose the notion of document structural similarity, which is expected to\\u000a further evaluate document similarity by comparing document subtopic

Xiaojun Wan

2008-01-01

343

River condition assessment may depend on the sub-sampling method: field live-sort versus laboratory sub-sampling of invertebrates for bioassessment  

Microsoft Academic Search

Aquatic macroinvertebrates are commonly used biological indicators for assessing the health of freshwater ecosystems. However,\\u000a counting all the invertebrates in the large samples that are usually collected for rapid site assessment is time-consuming\\u000a and costly. Therefore, sub-sampling is often done with fixed time or fixed count live-sorting in the field or with preserved\\u000a material using sample splitters in the laboratory.

Susan J. Nichols; Richard H. Norris

2006-01-01

344

Homology-dependent DNA Transfer from Plants to a Soil Bacterium Under Laboratory Conditions: Implications in Evolution and Horizontal Gene Transfer  

Microsoft Academic Search

DNA transfer was demonstrated from six species of donor plants to the soil bacterium, Acinetobacter spp. BD413, using neomycin phosphotransferase (nptII) as a marker for homologous recombination. These laboratory results are compatible with, but do not prove, DNA transfer in nature. In tobacco carrying a plastid insertion of nptII, transfer was detected with 0.1 g of disrupted leaves and in

David Tepfer; Rolando Garcia-Gonzales; Hounayda Mansouri; Martina Seruga; Brigitte Message; Francesca Leach; Mirna Curkovic Perica

2003-01-01

345

Effect of Azadirachta indica (neem), sodium thiosulphate and calcium chloride on changes in nitrogen transformations and inhibition of nitrification in soil incubated under laboratory conditions  

Microsoft Academic Search

A laboratory experiment was conducted to examine the effects of nitrification inhibitors (NIs) neem seedcake (Azadirachta indica) (NSC), sodium thiosulphate (Na2S2O3) and calcium chloride (CaCl2) on changes in NH4+N, inhibition of nitrification and recovery of applied nitrogen (N) in soil. Surface soil samples of 015cm were collected from an arable field, amended with urea N (UN) at the rate 200mgNkg?1,

M. Kaleem Abbasi; Munazza Hina; Majid Mahmood Tahir

2011-01-01

346

Commentaries on quantum similarity (1): Density gradient quantum similarity.  

PubMed

Computation of density gradient quantum similarity integrals is analyzed, while comparing such integrals with overlap density quantum similarity measures. Gradient quantum similarity corresponds to another kind of numerical similarity assessment between a pair of molecular frames, which contrarily to the usual up to date quantum similarity definitions are not measures, that is: strictly positive definite integrals. As the density gradient quantum similarity integrals are defined as scalar products of three real functions, they appear to possess a richer structure than the corresponding positive definite density overlap quantum similarity measures, while preserving the overall similarity trends, when the molecular frames are relatively moved in three-dimensional space. Similarity indices are also studied when simple cases are analyzed in order to perform more comparisons with density overlap quantum similarity. Multiple gradient quantum similarity integrals are also defined. General GTO formulae are given. Numerical results within the atomic shell approximation (ASA) framework are presented as simple examples showing the new performances of the gradient density quantum similarity. Fortran 90 programs illustrating the proposed theoretical development can be downloaded from appropriate websites. PMID:20336768

Carb-Dorca, Ramon; Mercado, Luz Dary

2010-08-01

347

The Effect of Bt-corn on Soil Invertebrates, Soil Microbial Community and Decomposition Rates of Corn PostHarvest Residues Under Field and Laboratory Conditions  

Microsoft Academic Search

Effects of Bt corn on post-harvest residues' decomposition, soil microflora, and soil fauna were studied in two field experiments in the Czech Republic. At each experiment location, Bt corn and a non-Bt conventional corn hybrid with a similar genetic background were each planted on half of a field, which was repeated at both locations for 3 years. Field microcosms containing

Jan Frouz; Dana Elhottov; Monika Helingerov; Frantiek Kocourek

2008-01-01

348

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 GOSTON; Lszl KAJN; Oliviero CARUGO; Zoltn HEGEDS

349

Predation by Podisus maculiventris (Say) (Hemiptera: Pentatomidae) on viburnum leaf beetle, Pyrrhalta viburni (Paykull) (Coleoptera: Chrysomelidae), under laboratory and field conditions.  

PubMed

To evaluate the potential of Podisus maculiventris (Say) (Heteroptera: Pentatomidae) as a biological control agent against viburnum leaf beetle, Pyrrhalta viburni (Paykull) (Coleoptera: Chrysomelidae), laboratory trials were conducted to measure prey consumption of P. maculiventris over nymphal development. Field trials tested the impact of augmentative releases of P. maculiventris nymphs on populations of P. viburni, using both open shrubs and caged branches of Viburnum trilobum. In the laboratory, P. maculiventris nymphs successfully developed while preying on P. viburni larvae and adults. Each nymph consumed an average of 100.6 larvae or 16.9 adults. Immature development duration was comparable between nymphs feeding on P. viburni adults and those given Galleria mellonella (L.) (Lepidoptera: Pyralidae) larvae as prey. In field trials, inundative releases of 30 P. maculiventris nymphs on naturally infested V. trilobum shrubs significantly reduced pest defoliation on shrubs infested with < 3,000 larvae but had no effect on shrubs with heavier infestations. On caged branches, individual nymphs successfully developed when feeding only on P. viburni larvae. These results show that P. viburni larvae and adults are suitable prey for P. maculiventris and this predator could potentially be developed as a biological control agent against P. viburni. PMID:19036203

Desurmont, Gaylord; Weston, Paul A

2008-10-01

350

Roget's thesaurus and semantic similarity  

Microsoft Academic Search

We have implemented a system that measures semantic similarity using a computerized 1987 Roget's Thesaurus , and evaluated it by performing a few typical tests. We compare the results of these tests with those produced by WordNet -based similarity measures. One of the benchmarks is Miller and Charles' list of 30 noun pairs to which human judges had assigned similarity

Mario Jarmasz; Stan Szpakowicz

2003-01-01

351

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

352

Laboratory Reagents  

SciTech Connect

Replaced by WMH-310, Section 4.17. This document outlined the basic methodology for preparing laboratory reagents used in the 222-S Standards Laboratory. Included were general guidelines for drying, weighing, transferring, dissolving, and diluting techniques common when preparing laboratory reagents and standards. Appendix A contained some of the reagents prepared by the laboratory.

CARLSON, D.D.

1999-10-08

353

Adenylate energy charge and adenine nucleotide measurements as indicators of stress in the mussel, Mytilus edulis , treated with dredged material under laboratory conditions  

Microsoft Academic Search

A biochemical marker or indicator of stress such as the adenylate energy charge (AEC) (Atkinson 1977) can be used to gain information on the physiological condition of an organism prior to the occurrence of irreversible changes. An indicator such as AEC may provide an integrated estimate of effects of interactions between pollutants and environmental factors as occurs in field situations.

Gerald E. Zaroogian; Mary Johnson

1989-01-01

354

Transgenic rice plants expressing a fused protein of Cry1Ab/Vip3H has resistance to rice stem borers under laboratory and field conditions.  

PubMed

Six transgenic rice, Oryza sativa L., lines (G6H1, G6H2, G6H3, G6H4, G6H5, and G6H6) expressing a fused Cry1Ab/Vip3H protein, were evaluated for resistance against the Asiatic rice borer, Chilo suppressalis (Walker) (Lepidoptera: Crambidae), and the stem borer Sesamia inferens (Walker) (Lepidoptera: Noctuidae) in the laboratory and field. The bioassay results indicated that the mortality of Asiatic rice borer and S. inferens neonate larvae on six transgenic lines from seedling to filling stage was up to 100% at 168 h after infestation. The cumulative feeding area by Asiatic rice borer neonate larvae on all transgenic lines was significantly reduced compared with the untransformed parental 'Xiushui 110' rice. A 2-yr field evaluation showed that damage during the vegetative stage (deadheart) or during the reproductive stage (whitehead) caused by Asiatic rice borer and S. inferens for transgenic lines was much lower than the control. For three lines (G6H1, G6H2, and G6H6), no damage was found during the entire growing period. Estimation of fused Cry1Ab/Vip3H protein concentrations using PathoScreen kit for Bt-Cry1Ab/1Ac protein indicated that the expression levels of Cry1Ab protein both in main stems (within the average range of 0.006-0.073% of total soluble protein) and their flag leaves (within the average range of 0.001-0.038% of total soluble protein) were significantly different among six transgenic lines at different developmental stages. Both laboratory and field researches suggested that the transgenic rice lines have considerable potential for protecting rice from attack by both stem borers. PMID:20857760

Chen, Yang; Tian, Jun-Ce; Shen, Zhi-Chen; Peng, Yu-Fa; Hu, Cui; Guo, Yu-Yuan; Ye, Gong-Yin

2010-08-01

355

Enhanced repellency of binary mixtures of Zanthoxylum armatum seed oil, vanillin, and their aerosols to mosquitoes under laboratory and field conditions.  

PubMed

The repellency of Zanthoxylum armatum seed oil (ZA-SO), alone or in combination with vanillin (VA), its six major constituents, and another four major previously known Zanthoxylum piperitum fruit oil constituents, as well as aerosol products containing 5 or 10% ZA-SO and 5% VA, was evaluated against female Aedes aegypti in laboratory and field studies. Results were then compared with those of N,N-diethyl-3-methylbenzamide (DEET) as a standard. Hand in cage laboratory tests showed that 0.2, 0.1, and 0.05 mg/cm2 ZA-SO resulted in > 92% protection through 30-min postexposure and was not significantly different than 0.05 mg/cm2 DEET. Skin treated with linalool and limonene (from Z. armatum) provided > 80% repellency to female Ae. aegypti at 10-min exposure, whereas cuminaldehyde, citronellal, geranyl acetate, and cuminyl alcohol (from Zanthoxylum piperitum) provided > 90% protection during this same time period. Only cuminaldehyde and citronellal provided complete protection comparable to DEET at 10-min postexposure. After that time, repellency of all plant constituents to mosquitoes was considerably decreased (< approximately 65%). An increase in repellency and duration of effectiveness was produced by a binary 1:4 mixture of ZA-SO and VA (0.05:0.2 mg/cm2) that was significantly more effective than 0.05 mg/cm2 DEET through 90 min. In field tests, an aerosol formulation containing 5 or 10% ZA-SO plus 5% VA gave 100% repellency at 60-min postexposure. Although these formulations were equal to the level of protection afforded by 10% DEET, repellency to the binary ZA-SO aerosol formulations at 90 min was significantly less effective than DEET. However, mixtures formulated from ZA-SO and VA merit further study as potential repellents for protection of humans and domestic animals from biting and nuisance caused by mosquitoes. PMID:21337949

Kwon, Hyung Wook; Kim, Soon-Il; Chang, Kyu-Sik; Clark, J Marshall; Ahn, Young-Joon

2011-01-01

356

Determining velocity gradients in laboratory and full-scale systems  

Microsoft Academic Search

Simulation of plant flocculators can be accomplished by using jar testing equipment. Similar conditions should be maintained between laboratory and full-scale work. In this article several G curves for jar testing are presented that allow different small-scale geometries to be used. Power curves were also developed and correlated to power numbers available in the literature for large impellers. Subsequently, a

David A. Cornwell; Mark M. Bishop

1983-01-01

357

Study on the overlap between apparent similarity and functional similarity  

NASA Astrophysics Data System (ADS)

Catchment similarity can be defined as apparent similarity as well as functional similarity. Apparent similarity is defined on the basis of observable catchment descriptors, while functional similarity could be formulated by using dependence measures of discharge series or judged through the utilization of hydrological models. Regionalization approaches are usually based on the assumption that model parameters can be linked to catchment properties. Unfortunately these procedures are very diverse. The objective of this study is to increase our knowledge about the overlap between apparent similarity and functional similarity. Firstly, the functional similarity of a large set of catchments is identified by model parameters. The water balance and the dynamic behavior are separated, and the simultaneous calibration is performed for a number of catchments. Result shows that catchments form several different groups - with common dynamic parameters for all members of the same group. Based on these, the fuzzy rule-based algorithm and depth function methodology will be applied to investigate the extent to which physiographic catchment properties or what kind combination of them significantly represents catchment hydrological behavior.

Huang, Yingchun; Brdossy, Andrs; Wagener, Thorsten

2013-04-01

358

Scaling, Self-similarity, and Intermediate Asymptotics  

NASA Astrophysics Data System (ADS)

Scaling (power-type) laws reveal the fundamental property of the phenomena--self similarity. Self-similar (scaling) phenomena repeat themselves in time and/or space. The property of self-similarity simplifies substantially the mathematical modeling of phenomena and its analysis--experimental, analytical and computational. The book begins from a non-traditional exposition of dimensional analysis, physical similarity theory and general theory of scaling phenomena. Classical examples of scaling phenomena are presented. It is demonstrated that scaling comes on a stage when the influence of fine details of initial and/or boundary conditions disappeared but the system is still far from ultimate equilibrium state (intermediate asymptotics). It is explained why the dimensional analysis as a rule is insufficient for establishing self-similarity and constructing scaling variables. Important examples of scaling phenomena for which the dimensional analysis is insufficient (self-similarities of the second kind) are presented and discussed. A close connection of intermediate asymptotics and self-similarities of the second kind with a fundamental concept of theoretical physics, the renormalization group, is explained and discussed. Numerous examples from various fields--from theoretical biology to fracture mechanics, turbulence, flame propagation, flow in porous strata, atmospheric and oceanic phenomena are presented for which the ideas of scaling, intermediate asymptotics, self-similarity and renormalization group were of decisive value in modeling.

Barenblatt, Grigory Isaakovich

1996-12-01

359

Laboratory Experiments on Magnetic Reconnection  

NASA Astrophysics Data System (ADS)

Magnetic reconnection, a topological rearrangement of magnetic field lines, is one of the key self-organization processes in laboratory and astrophysical plasmas. This talk presents the fundamental physics of magnetic reconnection reviewing the recent significant progress in laboratory experiments. Sawtooth relaxation in a tokamak plasma, which represents a repetitive change of the electron temperature profile, provides a good example of magnetic reconnection. During the relaxation phase of the sawtooth, a rapid flattening of the electron temperature profile occurs and the pitch of field lines changes suddenly as the field lines break and rearrange themselves to form a new topological profile. In the reversed field pinch (RFP) and spheromak plasmas, a sudden re-arrangement of field lines in an inner flux surface can trigger another rearrangement in the outer flux surfaces, leading to a global magnetic relaxation event. Magnetic reconnection physics has been investigated in a variety of laboratory experiments dedicated for reconnection research. These laboratory experiments have made important contributions to recent advances in our understanding of magnetic reconnection. Significant findings are as follows: 1) The reconnection dynamics are determined both by local and global conditions, 2) The profiles of the reconnection layer and reconnection rate change drastically as the plasma's collisionality is reduced, 3) Two-fluid dynamics have been verified through experimental identification of both the ion and electron diffusion layers, 4) Electrostatic and electromagnetic fluctuations and their spatial profiles were measured in the reconnection layer of both laboratory and space plasmas with notable similarities, and 5) The reconnection rate increases significantly when the ratio of the electron mean free path to the scale length approaches unity. A new scaling of reconnection resistivity with respect to this ratio has been obtained from the laboratory results. The impact of this recently advanced understanding on research on space-terrestrial plasmas will be discussed.

Yamada, Masaaki

2010-05-01

360

Nontarget effect of entomopathogenic nematodes on larvae of twospotted lady beetle (Coleoptera: Coccinellidae) and green lacewing (Neuroptera: Chrysopidae) under laboratory conditions.  

PubMed

The nontarget effect of Steinernema feltiae, Steinernema carpocapsae, Heterorhabditis bacteriophora, and three mixed suspensions of two species of entomopathogenic nematodes on the larvae of the twospotted lady beetle, Adalia bipunctata (L.) (Coleoptera: Coccinellidae), and on the larvae of the lacewing Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), were studied in a laboratory bioassay. The assay was performed at three temperature (15, 20, and 25 degrees C) and at three different concentrations of the suspension (500, 2,500, and 5,000 infective juveniles [IJs]/ml). The larvae of A. bipunctata were more susceptible to nematode attack than the larvae of C. carnea. Four days after treatment, significantly the lowest mortality of A. bipunctata and C. carnea larvae was recorded at 15 degrees C, whereas no significant differences were noted between 20 and 25 degrees C. At 500 IJs/ml, the nematodes had significantly the lowest nontarget effect on the larvae of both aphid predators, whereas no significant differences in this regard were established between 2,500 and 5,000 IJs/ml. We conclude that the entomopathogenic nematodes under investigation exhibit a pronounced nontarget effect on the larvae of both predators mentioned. PMID:19736754

Rojht, Helena; Kac, Milica; Trdan, Stanislav

2009-08-01

361

Hydrologic Conditions and Distribution of Selected Constituents in Water, Snake River Plain Aquifer, Idaho National Engineering and Environmental Laboratory, Idaho, 1996 through 1998  

SciTech Connect

Radiochemical and chemical wastewater discharged since 1952 to infiltration ponds and disposal wells at the Idaho National Engineering and Environmental Laboratory (INEEL) 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 INEEL to determine hydrologic trends and to delineate the movement to 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 1996-98. Detectable concentrations of radiochemical constituents in water samples from wells in the Snake River Plain aquifer at the INEEL decreased or remained constant during 1996-98. Decreased concentrations are attributed to reduced rates of radioactive-waste disposal, sorption process, radioactive decay, and changes in waste-disposal practices. Detectable concentrations of chemical constituents in water from the Snake River Plain aquifer at the INEEL were variable during 1996-98.

R. C. Bartholomay; B. J. Tucker; L. C. Davis; M. R. Greene

2000-09-01

362

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 (2182 K) and pressure (61 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 231110 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 2.181.4510-3 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

363

Assay conditions in laboratory experiments: is the use of constant rather than fluctuating temperatures justified when investigating temperature-induced plasticity?  

PubMed

Temperature is an important selective agent in nature. Consequently, temperature-induced plasticity which may help buffering detrimental effects of temperature variation has received considerable attention over recent decades. Laboratory studies have almost exclusively used constant temperatures, while in nature, temperature typically shows pronounced daily fluctuations. Using a factorial design with constant versus fluctuating temperatures and a higher versus a lower mean temperature, we here investigate in the butterfly Lycaena tityrus whether the use of constant temperatures is justified. Fluctuating compared to constant temperatures caused shorter development times, increased heat but decreased cold stress resistance, decreased heat-shock protein expression, and increased immunocompetence. Thus, overall, fluctuating temperatures were more beneficial to the butterflies compared to constant ones. However, despite substantial variation across temperature regimes, the ranking of trait values among treatments remained largely unaffected (e.g. lower constant as well as fluctuating temperatures caused increased pupal mass). Thus, we tentatively conclude that there is no general reason for concern about using constant temperatures in studies investigating phenotypic plasticity, which seem to comprise a fair proxy. However, substantial differences in mean values as well as interactive effects suggest that one needs to be cautious. We further demonstrate negative effects of high temperatures on butterfly immune function, which seem to result from a trade-off between the latter and the heat shock response. PMID:21286923

Fischer, Klaus; Klzow, Nadine; Hltje, Henriette; Karl, Isabell

2011-02-01

364

SIMILARITY BASED ON RATING DATA  

Microsoft Academic Search

This paper describes an algorithm to measure the similar- ity of two multimedia objects, such as songs or movies, using users' preferences. Much of the previous work on query-by-example (QBE) or music similarity uses detailed analysis of the object's content. This is difficult and it is often impossible to capture how consumers react to the music. We argue that a

Malcolm Slaney; William White

2007-01-01

365

Similarity between Hypotheses and Evidence  

Microsoft Academic Search

We explore two novel consequences of similarity-based likelihood judgment. In Section I, we distinguish between theevidenceon which judgments are based and thehypothesesthat serve as the objects of judgment. The location of a feature, whether in the evidence or the hypotheses, influences the perceived similarity between evidence and hypotheses and consequently yields judgments that are inconsistent with the requirements of probability

Yuval Rottenstreich; Lyle Brenner; Sanjay Sood

1999-01-01

366

Bioconcentration of two pharmaceuticals (benzodiazepines) and two personal care products (UV filters) in marine mussels (Mytilus galloprovincialis) under controlled laboratory conditions.  

PubMed

Bioaccumulation is essential for gaining insight into the impact of exposure to organic micropollutants in aquatic fauna. Data are currently available on the bioaccumulation of persistent organic pollutants, but there is very little documentation on the bioaccumulation of pharmaceuticals and personal care products (PPCPs). The bioconcentration of selected PPCPs was studied in marine mussels (Mytilus galloprovincialis). The selected PPCPs were two organic UV filters, i.e., 2-ethylhexyl-4-trimethoxycinnamate (EHMC) and octocrylene (OC), and two benzodiazepines (BZP), i.e., diazepam (DZP) and tetrazepam (TZP). Laboratory experiments were performed in which M. galloprovincialis was exposed to these compounds either directly from water, for the less lipophilic substances (BZP) or via spiked food for lipophilic UV filters. M. galloprovincialis uptook and eliminated BZP following first-order kinetics. The biological half-life (t (1/2)) of TZP was 1.4days, resulting in a bioconcentration factor of 64 and 99mLg(-1) dry weight (dw), respectively, for 2.3 and 14.5?gL(-1) of exposure, while the biological half-life (t (1/2)) of DZP was 0.4days, resulting in a bioconcentration factor of 51mLg(-1) dw for 13.2?gL(-1) of exposure. The uptake of UV filter was rapid in mussels, followed by elimination within 24h. EHMC increased from 15 to 138ngg(-1) dw in 1h and decreased to 25ngg(-1) after 24h for 11.9?gL(-1) exposure. OC reached 839ngg(-1) dw after 1h and decreased to 33ngg(-1) after 24h for 11.6?gL(-1) exposure. However, EHMC and OC were slightly accumulated in 48h, i.e., 38 and 60ngg(-1) dw, respectively. PMID:22828885

Gomez, Elena; Bachelot, Morgane; Boillot, Clotilde; Munaron, Dominique; Chiron, Serge; Casellas, Claude; Fenet, Hlne

2012-08-31

367

FINAL REPORT - Biogeochemistry of Uranium Under Reducing and Re-oxidizing Conditions:An Integrated Laboratory and Field Study and Acceptable Endpoints for Metals and Radionuclides: Quantifying the Stability of Uranium and Lead Immobilized Under Sulfate Reducing Conditions  

SciTech Connect

Our understanding of subsurface microbiology is hindered by the inaccessibility of this environment, particularly when the hydrogeologic medium is contaminated with toxic substances. Research in our labs indicated that the composition of the growth medium (e.g., bicarbonate complexation of U(VI)) and the underlying mineral phase (e.g., hematite) significantly affects the rate and extent of U(VI) reduction and immobilization through a variety of effects. Our research was aimed at elucidating those effects to a much greater extent, while exploring the potential for U(IV) reoxidation and subsequent re-mobilization, which also appears to depend on the mineral phases present in the system. In situ coupons with a variety of mineral phases were placed in monitoring wells at the NABIR FRC. These coupons showed that the mineral phase composition significantly affected the resulting attached phase microbial community. Our comparative use of both batch and open flow reactors (more representative of field conditions) indicates that hydrodynamics and continual influx of substrate and contaminants can also yield significantly different results than those obtained with closed serum bottles. To this end, the following overall experimental hypothesis tested was the following: On a mineral surface under anaerobic conditions, accumulations of secondary inorganic precipitates are controlled by a) the bacteria associated with the mineral surface, b) the electron acceptors available for anaerobic bacterial respiration, and c) local hydrodynamics and pH buffers govern micro- and meso-scale interaction of U in the presence of electron donors and acceptors, and nutrients.

Brent Peyton; James Amonette; Haluk Beyenal; Gill Geesey; Zbigniew Lewandowski; Rajesh Sani

2005-10-07

368

Renewing the respect for similarity  

PubMed Central

In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemming from its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problem at hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, by surveying established results and new developments in the theory and methods of similarity-preserving associative lookup and dimensionality reductioncritical components of many cognitive functions, as well as of intelligent data management in computer vision. We focus in particular on the growing family of algorithms that support associative memory by performing hashing that respects local similarity, and on the uses of similarity in representing structured objects and scenes. Insofar as these similarity-based ideas and methods are useful in cognitive modeling and in AI applications, they should be included in the core conceptual toolkit of computational neuroscience. In support of this stance, the present paper (1) offers a discussion of conceptual, mathematical, computational, and empirical aspects of similarity, as applied to the problems of visual object and scene representation, recognition, and interpretation, (2) mentions some key computational problems arising in attempts to put similarity to use, along with their possible solutions, (3) briefly states a previously developed similarity-based framework for visual object representation, the Chorus of Prototypes, along with the empirical support it enjoys, (4) presents new mathematical insights into the effectiveness of this framework, derived from its relationship to locality-sensitive hashing (LSH) and to concomitant statistics, (5) introduces a new model, the Chorus of Relational Descriptors (ChoRD), that extends this framework to scene representation and interpretation, (6) describes its implementation and testing, and finally (7) suggests possible directions in which the present research program can be extended in the future.

Edelman, Shimon; Shahbazi, Reza

2012-01-01

369

Renewing the respect for similarity.  

PubMed

In psychology, the concept of similarity has traditionally evoked a mixture of respect, stemming from its ubiquity and intuitive appeal, and concern, due to its dependence on the framing of the problem at hand and on its context. We argue for a renewed focus on similarity as an explanatory concept, by surveying established results and new developments in the theory and methods of similarity-preserving associative lookup and dimensionality reduction-critical components of many cognitive functions, as well as of intelligent data management in computer vision. We focus in particular on the growing family of algorithms that support associative memory by performing hashing that respects local similarity, and on the uses of similarity in representing structured objects and scenes. Insofar as these similarity-based ideas and methods are useful in cognitive modeling and in AI applications, they should be included in the core conceptual toolkit of computational neuroscience. In support of this stance, the present paper (1) offers a discussion of conceptual, mathematical, computational, and empirical aspects of similarity, as applied to the problems of visual object and scene representation, recognition, and interpretation, (2) mentions some key computational problems arising in attempts to put similarity to use, along with their possible solutions, (3) briefly states a previously developed similarity-based framework for visual object representation, the Chorus of Prototypes, along with the empirical support it enjoys, (4) presents new mathematical insights into the effectiveness of this framework, derived from its relationship to locality-sensitive hashing (LSH) and to concomitant statistics, (5) introduces a new model, the Chorus of Relational Descriptors (ChoRD), that extends this framework to scene representation and interpretation, (6) describes its implementation and testing, and finally (7) suggests possible directions in which the present research program can be extended in the future. PMID:22811664

Edelman, Shimon; Shahbazi, Reza

2012-07-13

370

Battery testing at Argonne National Laboratory.  

National Technical Information Service (NTIS)

Argonne National Laboratory's Analysis & Diagnostic Laboratory (ADL) tests advanced batteries under simulated electric and hybrid vehicle operating conditions. The ADL facilities also include a post-test analysis laboratory to determine, in a protected at...

W. H. DeLuca K. R. Gillie J. E. Kulaga J. A. Smaga A. F. Tummillo

1993-01-01

371

Subterranean microbial populations metabolize hydrogen and acetate under in situ conditions in granitic groundwater at 450 m depth in the sp Hard Rock Laboratory, Sweden.  

PubMed

Pressure-resistant circulating systems were constructed to enable the investigation of attached and unattached microbial populations under in situ pressure (2.5 MPa), diversity, dissolved gas and chemistry conditions. Three parallel flow cell cabinets were configured to allow observation of the effect on microbial metabolic activity of adding 3 mM hydrogen or 2.4 mM acetate, compared with an untreated control. Hydrogen addition reduced the generation time fourfold to 2 weeks, doubled the sulphide production rate and increased acetate production by approximately 50%. The acetate addition induced acetate consumption. The studied subterranean microbial processes appeared to proceed very slowly in terms of volume and time, although the results suggest that individual cells could be very active. Lytic bacteriophages are hypothesized to have caused this contradictive observation. Phages may consequently significantly reduce the rates of subterranean microbial processes. Furthermore, the results suggest that hydrogen from corroding underground constructions could induce significant local microbial activity and that the low concentrations of hydrogen often observed in pristine subterranean environments may support slow but sustainable microbial activity in deep groundwater. PMID:22452510

Pedersen, Karsten

2012-04-19

372

Similarity judgments serving eyewitness identification  

NASA Astrophysics Data System (ADS)

Current police tools of identification are flawed. The lineup suffers from being too small and no adequate solution to a criterion of similar foils. The mugshot search suffers from too many photos and inadequate procedures for choosing an appropriate subset. The composite, from inappropriate methods of selecting facial features. Our new mugshot search provides solutions to some of the problems. Witnesses choose photos similar to the offender, and the computer, using a similarity network, helps witnesses reach the offender faster. Replacing mugshots with foils, we can use the same technique as a lineup, that is significantly enlarged and leaves the choice of similar foils to the witnesses. When the mugshot search fails, a composite can be composed as a superimposition of the photos most similar to the offender. Several algorithms were tested for implementing the similarity network. They involve both the establishment of a meaningful distance criterion within 'face space' and the usage of efficient search strategies. Here, we discuss their benefits and drawbacks. A system comprising the full local album of the Haifa district (more than 10,000 photos) is presently being subjected to a field test by the Isreali police. We briefly describe the system and its user interface.

Levi, Avraham; Jungmann, Noam; Aperman, Arie

1995-09-01

373

Retrospective Clinical and Molecular Analysis of Conditioned Laboratory Dogs (Canis familiaris) with Serologic Reactions to Ehrlichia canis, Borrelia burgdorferi, and Rickettsia rickettsii  

PubMed Central

Dogs are susceptible to different tickborne infections, including members of the Anaplasmataceae (Ehrlichia canis, E. ewingii, E. chaffeensis, Anaplasma phagocytophilum, A. platys), Borrelia burgdorferi, and Rickettsia rickettsii. These diseases can manifest with clinical signs including fever, anorexia, malaise, lameness, rash, and bleeding episodes; however, these signs are nonpathognomonic, and infections can occur in the absence of clinical signs. Hematologic abnormalities can include leukopenia, thrombocytopenia, hyperproteinemia and hypergammaglobulinemia. In biomedical research, diseases such as canine monocytic ehrlichiosis, Lyme disease, and Rocky Mountain spotted fever may cause morbidity among exposed dogs and confound research results. Random-source dogs are susceptible to these diseases because of their increased risk of arthropod exposure. Nonpurpose bred, randomly selected conditioned dogs (n = 21) were examined; blood samples were taken for hematology, biochemistry analysis, tickborne pathogen serology, and PCR. Of these, 2 dogs (10% of the population) presented with illness characterized by fever, malaise, lameness, or hemostatic abnormalities, and 15 (71%) had antibodies to one or more tickborne pathogens. No specific hematologic or biochemical differences were apparent between seronegative dogs and seropositive dogs reactive to all 3 pathogens. E. canis and B. burgdorferi PCR of tissues and blood were negative for all dogs. PCR amplification of several Ehrlichia and Anaplasma genes yielded no positive samples. From this cohort of dogs, serologic and molecular results indicate prior exposure without active infection or clinical disease. Exposure to and potential for infection with these bacteria and other pathogens may contribute to blood and tissue alterations that could confound experiments and lead to misinterpretation of data in canine models.

Scorpio, Diana G; Wachtman, Lynn M; Tunin, Richard S; Barat, Nicole C; Garyu, Justin W; Dumler, J Stephen

2008-01-01

374

Technical Note: On Estimating Conditions for Simulating Velocity-Sensitive Corrosion in the Rotating Cylinder Electrode  

Microsoft Academic Search

Simulation of velocity-sensitive corrosion in the laboratory for predicting similar corrosion in the field is of ongoing interest. Such an approach seems to be especially practical when corrosion is controlled by the rate of mass transport to or from the surface. Such control, when measured under appropriate conditions in the laboratory, should be observed in the field. The present research

D. C. Silverman

1999-01-01

375

Exponentially self-similar impact ionization waves  

SciTech Connect

The existence of generalized self-similar solutions to the system of continuity and Poisson equations is analyzed for the problem of evolution of impact ionization waves (IIWs). It is shown that, for any physically reasonable electric-field dependence of the impact ionization coefficients, there exist only exponentially self-similar ('limiting') asymptotic solutions. These solutions describe IIWs whose spatial scales and propagation velocities increase exponentially with time. Conditions are found for the existence of plane, cylindrical, and spherical waves of this type; their structure is described; analytical relations between the key parameters are derived; and effects of recombination (or attachment) and tunnel ionization are analyzed. It is shown that these IIWs are intermediate asymptotics of numerical solutions to the corresponding Cauchy problems. The most important and interesting type of exponentially self-similar IIWs are streamers in a uniform electric field. The simplest comprehensive and explicit model describing their evolution is a spherical IIW.

Kyuregyan, A. S., E-mail: ask@vei.r [All-Russia Institute of Electrical Engineering (Russian Federation)

2010-04-15

376

A generative theory of similarity  

Microsoft Academic Search

We argue that similarity judgments are inferences about generative processes, and that two objects appear sim- ilar when they are likely to have been generated by the same process. We describe a formal model based on this idea and show how featural and spatial models emerge as special cases. We compare our approach to the transformational approach, and present an

Charles Kemp; Aaron Bernstein; Joshua B. Tenenbaum

377

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

378

Similarity Indexing: Algorithms and Performance  

Microsoft Academic Search

Efficient indexing support is essential to allow content-based image and video databases using similarity- based retrieval to scale to large databases (tens of thousands up to millions of images). In this paper, we take an in depth look at this problem. One of the major difficulties in solving this problem is the high dimension (6-100) of the feature vectors that

David A. White; Ramesh Jain

1996-01-01

379

Similarity Retrieval of Trademark Images  

Microsoft Academic Search

We investigate the hypothesis that the low-level image features used to index the trademark images can be correlated with image contents by applying a relevance feedback mechanism that evaluates the feature distributions of the images judged relevant, or not relevant, by the user, and dynamically updates both the similarity measure and query in order to better represent the user's particular

Gianluigi Ciocca; Raimondo Schettini

1999-01-01

380

Water Chemistry Laboratory Manual.  

ERIC Educational Resources Information Center

|This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar

Jenkins, David; And Others

381

Water Chemistry Laboratory Manual.  

ERIC Educational Resources Information Center

This manual of laboratory experiments in water chemistry serves a dual function of illustrating fundamental chemical principles of dilute aqueous systems and of providing the student with some familiarity with the chemical measurements commonly used in water and wastewater analysis. Experiments are grouped in categories on the basis of similar

Jenkins, David; And Others

382

Similarity Measurement for Animation Movies  

Microsoft Academic Search

\\u000a When considering the quantity of multimedia content that people and professionals accumulate day by day on their storage devices,\\u000a the necessity of appropriate intelligent tools for searching or navigating, becomes an issue. Nevertheless, the richness of\\u000a such media is difficult to handle with todays video analysis algorithm. In this context, we propose a similarity measure\\u000a dedicated to animation movies. This

Alexandre Benoit; Madalina Ciobotaru; Patrick Lambert; Bogdan Ionescu

2011-01-01

383

GROWTH EFFICIENCY IN ARTEMIA UNDER LABORATORY CONDITIONS  

Microsoft Academic Search

Measurements of the efficiency with which animals can convert food into their own body tissue have been largely confined to the vertebrates of agricultural im portance. Typical of the wealth of data in Brody (1945) are figures for milk production in cows of 33%, egg production in liens of 10%, and for Jersey cows from 0 to 2 years an

MICHAEL R. REEVE

384

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.

385

Rethinking Laboratories.  

ERIC Educational Resources Information Center

Presents an inquiry analysis tool and adaptation principles to help teachers evaluate and adapt laboratory instructional materials to be more inquiry-oriented. Based on the National Research Council's (NRC) essential features of inquiry. (NB)

Volkmann, Mark J.; Abell, Sandra K.

2003-01-01

386

Laboratory Methods  

Center for Food Safety and Applied Nutrition (CFSAN)

The FDA sets scientific standards for testing foods for various contaminants. Laboratories and food companies worldwide use these standards to make ... More results from www.fda.gov/food/foodscienceresearch/laboratorymethods

387

Rethinking Laboratories  

NSDL National Science Digital Library

Although research demonstrates the value of inquiry-based science, many curriculum materials are still based on traditional approaches that fail to engage students in inquiry. Using an example of a typical cookbook laboratory--the "rusty nail," this article describes an inquiry analysis tool and adaptation principles that were created to help teachers evaluate and adapt laboratory instructional materials to be more inquiry-oriented.

Volkmann, Mark J.; Abell, Sandra K.

2003-09-01

388

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. Mller

389

Laboratory system for dust generation from soils.  

PubMed

Farm workers and residential communities adjacent to agricultural fields can be exposed to soil dust generated during field operations at levels that could result in respiratory problems. However, field sampling of agricultural dust faces logistical problems from spatial and temporal differences in soil properties, field operations, and meteorological conditions. To minimize these problems, we designed a dust generator that simulates dust generation during tilling of agricultural fields to provide samples of particulate matter derived from bulk soil and developed optimal operating conditions to assure reproducible results. The dust generator consisted of a rotating chamber, where soil samples were loaded and tumbled, and a settling chamber, where airborne soil dust samples were collected using particle size-selective samplers. The following operating conditions for dust generation were evaluated: initial soil mass, air intake, rotation speed, and sampling time to optimize dust sampling. We compared the laboratory-generated dust from soil samples with field dust that we collected from the same plots during agricultural operations. We determined from X-ray diffraction and energy-dispersive X-ray analyses that the mineralogy and chemical composition of field- and laboratory-generated dust were similar, indicating that the apparatus reasonably simulated field mechanical processes that produce airborne particulate matter from soils. The results suggest that the laboratory dust generator provides reliable samples of soil-derived dust and could be useful for future studies involving airborne particulate material from soils. PMID:20830913

Domingo, Rebecca A; Southard, Randal J; Lee, Kiyoung

390

Laboratory Safety and Management  

ERIC Educational Resources Information Center

|Explains a scientific approach to accident prevention and outlines the safety aspects associated with the handling of chemicals in the secondary school. Provides a check list of unsafe acts and conditions, outlines features of good laboratory management, and gives hints for combating the effects of inflation on science budgets. (GS)|

Goodenough, T. J.

1976-01-01

391

Similarity indexing: algorithms and performance  

NASA Astrophysics Data System (ADS)

Efficient indexing support is essential to allow content-based image and video databases using similarity-based retrieval to scale to large databases (tens of thousands up to millions of images). In this paper, we take an in depth look at this problem. One of the major difficulties in solving this problem is the high dimension (6-100) of the feature vectors that are used to represent objects. We provide an overview of the work in computational geometry on this problem and highlight the results we found are most useful in practice, including the use of approximate nearest neighbor algorithms. We also present a variant of the optimized k-d tree we call the VAM k-d tree, and provide algorithms to create an optimized R-tree we call the VAMSplit R-tree. We found that the VAMSplit R-tree provided better overall performance than all competing structures we tested for main memory and secondary memory applications. We observed large improvements in performance relative to the R*-tree and SS-tree in secondary memory applications, and modest improvements relative to optimized k-d tree variants.

White, David A.; Jain, Ramesh C.

1996-03-01

392

Voice similarity in identical twins.  

PubMed

If people are asked to discriminate visually the two individuals of a monozygotic twin (MT), they mostly get into trouble. Does this problem also exist when listening to twin voices? Twenty female and 10 male MT voices were randomly assembled with one "strange" voice to get voice trios. The listeners (10 female students in Speech and Language Pathology) were asked to label the twins (voices 1-2, 1-3 or 2-3) in two conditions: two standard sentences read aloud and a 2.5-second midsection of a sustained /a/. The proportion correctly labelled twins was for female voices 82% and 63% and for male voices 74% and 52% for the sentences and the sustained /a/ respectively, both being significantly greater than chance (33%). The acoustic analysis revealed a high intra-twin correlation for the speaking fundamental frequency (SFF) of the sentences and the fundamental frequency (F0) of the sustained /a/. So the voice pitch could have been a useful characteristic in the perceptual identification of the twins. We conclude that there is a greater perceptual resemblance between the voices of identical twins than between voices without genetic relationship. The identification however is not perfect. The voice pitch possibly contributes to the correct twin identifications. PMID:11256192

Van Gysel, W D; Vercammen, J; Debruyne, F

2001-01-01

393

Evaluating Gender Discrimination Claims: Is There a Gender Similarity Bias?  

Microsoft Academic Search

A rich literature exists that examines individuals' perceptions of affirmative action in organizations. However, little is known regarding the evaluation of reverse gender discrimination claims arising from gender-based preferential treatment. This study investigated the possible existence of a gender similarity bias in evaluations of gender discrimination allegations using a laboratory experiment in which the strength of evidence against the defendant

Teri J. Elkins; James S. Phillips; Robert Konopaske; Joellyn Townsend

2001-01-01

394

Transcription in Archaea: Similarity to that in Eucarya  

Microsoft Academic Search

We present homologies between archaeal and eucaryal DNA-dependent RNA polymerase (RNAP) subunits and transcription factors. The sequences of the Sulfolobus acidocaldarius subunits D, E, and N and alignments with eucaryal homologs are presented here. The similarities between archaeal transcription factors and their eucaryal homologs TFIIB and TBP have been established in other laboratories. The archaeal RNAP subunits H, K, and

Doris Langer; Johannes Hain; Pierre Thuriaux; Wolfram Zillig

1995-01-01

395

Measuring sentence similarity from different aspects  

Microsoft Academic Search

The paper proposes to determine sentence similarities from different aspects. Based on the information people get from a sentence, objects-specified similarity, objects-property similarity, objects-behavior similarity and overall similarity are defined to determine sentence similarities from four aspects. Experiments show that the proposed method makes the sentence similarity comparison more exactly and give out a more reasonable result, which is similar

Lin Li; Xia Hu; Bi-Yun Hu; Jun Wang; Yi-Ming Zhou

2009-01-01

396

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.

397

Hydrodynamic Scalings: from Astrophysics to Laboratory  

NASA Astrophysics Data System (ADS)

A surprisingly general hydrodynamic similarity has been recently described in Refs. [1,2]. One can call it the Euler similarity because it works for the Euler equations (with MHD effects included). Although the dissipation processes are assumed to be negligible, the presence of shocks is allowed. For the polytropic medium (i.e., the medium where the energy density is proportional to the pressure), an evolution of an arbitrarily chosen 3D initial state can be scaled to another system, if a single dimensionless parameter (the Euler number) is the same for both initial states. The Euler similarity allows one to properly design laboratory experiments modeling astrophysical phenomena. We discuss several examples of such experiments related to the physics of supernovae [3]. For the problems with a single spatial scale, the condition of the smallness of dissipative processes can be adequately described in terms of the Reynolds, Peclet, and magnetic Reynolds numbers related to this scale (all three numbers must be large). However, if the system develops small-scale turbulence, dissipation may become important at these smaller scales, thereby affecting the gross behavior of the system. We analyze the corresponding constraints. We discuss also constraints imposed by the presence of interfaces between the substances with different polytropic index. Another set of similarities governs evolution of photoevaporation fronts in astrophysics. Convenient scaling laws exist in situations where the density of the ablated material is very low compared to the bulk density. We conclude that a number of hydrodynamical problems related to such objects as the Eagle Nebula can be adequately simulated in the laboratory. We discuss also possible scalings for radiative astrophysical jets (see Ref. [3] and references therein). This work was performed under the auspices of the U.S. Department of Energy by University of California Lawrence Livermore National Laboratory under contract W-7405-Eng-48. 1. D.D. Ryutov, R.P. Drake, J. Kane, E. Liang, B. A. Remington, and W.M. Wood-Vasey. "Similarity criteria for the laboratory simulation of supernova hydrodynamics." Astrophysical Journal, v. 518, p. 821 (1999). 2. D.D. Ryutov, R.P. Drake, B.A. Remington. "Criteria for scaled laboratory simulations of astrophysical MHD phenomena." To appear in Astrophysical Journal - Supplement, April 2000. 3. Remington, B.A., Phys. Plasmas, 7, # 5 (2000).

Ryutov, D. D.; Remington, B. A.

2000-05-01

398

Conceptual Similarity Promotes Generalization of Higher Order Fear Learning  

ERIC Educational Resources Information Center

|We tested the hypothesis that conceptual similarity promotes generalization of conditioned fear. Using a sensory preconditioning procedure, three groups of subjects learned an association between two cues that were conceptually similar, unrelated, or mismatched. Next, one of the cues was paired with a shock. The other cue was then reintroduced to

Dunsmoor, Joseph E.; White, Allison J.; LaBar, Kevin S.

2011-01-01

399

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

400

Laboratory reverie.  

PubMed

As a general rule, HMN believes you should avoid making the laboratory business separate from the practice and should maintain the lab technician on the same footing as the rest of the staff with regard to working hours and salary. However, this does not apply to every practice. Sometimes there are distinct advantages to channeling money out of your practice. The discussion above will help you to evaluate your individual situation. PMID:8059764

1994-08-01

401

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

402

Emergent self-similarity of cluster coagulation  

NASA Astrophysics Data System (ADS)

A wide variety of nonequilibrium processes, such as coagulation of colloidal particles, aggregation of bacteria into colonies, coalescence of rain drops, bond formation between polymerization sites, and formation of planetesimals, fall under the rubric of cluster coagulation. We predict emergence of self-similar behavior in such systems when they are 'forced' by an external source of the smallest particles. The corresponding self-similar coagulation spectra prove to be power laws. Starting from the classical Smoluchowski coagulation equation, we identify the conditions required for emergence of self-similarity and show that the power-law exponent value for a particular coagulation mechanism depends on the homogeneity index of the corresponding coagulation kernel only. Next, we consider the current wave of mergers of large American banks as an 'unorthodox' application of coagulation theory. We predict that the bank size distribution has propensity to become a power law, and verify our prediction in a statistical study of the available economical data. We conclude this chapter by discussing economically significant phenomenon of capital condensation and predicting emergence of power-law distributions in other economical and social data. Finally, we turn to apparent semblance between cluster coagulation and turbulence and conclude that it is not accidental: both of these processes are instances of nonlinear cascades. This class of processes also includes river network formation models, certain force-chain models in granular mechanics, fragmentation due to collisional cascades, percolation, and growing random networks. We characterize a particular cascade by three indicies and show that the resulting power-law spectrum exponent depends on the indicies values only. The ensuing algebraic formula is remarkable for its simplicity.

Pushkin, Dmtiri O.

403

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

404

42 CFR 493.1205 - Condition: Virology.  

Code of Federal Regulations, 2010 CFR

...2009-10-01 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...

2009-10-01

405

A qualitative characterization of an introductory college nonmajors biology laboratory  

NASA Astrophysics Data System (ADS)

The nature of an undergraduate, nonmajors biology laboratory was investigated in this study. Student participants were enrolled in a general education biology laboratory course at the University of Northern Iowa. The researcher's purpose was to gain a characterization of the instructional format and laboratory activities experienced by students. Interpretation of student and instructor responses enabled an insider's view of the biology laboratory. The laboratory period was consistently described by both students and instructors as having three parts, Beginning, Middle, and End, with the End being of special importance for conceptual development. The instructional format of the three instructors differed within the three portions of the laboratory period, ranging from an inquiry-oriented, partial learning cycle to a fairly expository model labeled inform/verify/practice. There was striking similarity in intrasectional student and teacher descriptions of instructional format. Additionally, students experiencing the alternate instructor provided the same characterizations of instructional format as those provided by the instructor's usual students. There were no discernible patterns of instructional format based on sex or reasoning level. In addition to the central role of instructional format, three areas of importance emerged: the social aspects of learning, the collaborative and cooperative nature of laboratory work and learning, and the role of self-efficacy. Theory developed from and grounded in the data showed six factors important in the introductory college biology laboratory: collaborative and cooperative learning, student-student and teacher-student interactions, attitude and self-efficacy, learning process and learning style, effective instructional format, and science content. These factors were found to be similar to factors identified in the literature as important in K-12 science education. These factors were set in the context of schooling and learning paradigms, paralleling J. J. Schwab's four conditions of a curriculum (subject matter, learners, teachers, and milieus), Benjamin Bloom's model of important factors in student achievement and schooling (cognitive entry behaviors, affective entry behaviors, and quality of instruction), and fitting a constructivist epistemological framework.

Lee, Cherin Ann

406

Thematic Relations Affect Similarity Via Commonalities  

Microsoft Academic Search

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 differences. In Experiment 1, thematic relations affected similarity more than difference, thereby producing

Sabrina Golonka; Zachary Estes

2009-01-01

407

Sentence Similarity Measurement Based on Shallow Parsing  

Microsoft Academic Search

The paper proposes a novel method to determine sentence similarities. First two compared sentences are parsed by shallow-parsing and all noun phrases, verb phrases and preposition phrases of each sentence are extracted. Then the similarity between each kind of phrases is calculated based on a semantic vector method. The overall sentence similarity is defined as a combination of semantic similarities

Lin Li; Yiming Zhou; Boqiu Yuan; Jun Wang; Xia Hu

2009-01-01

408

An Information-Theoretic Definition of Similarity  

Microsoft Academic Search

Similarity is an important and widely used con- cept. Previous definitions of similarity are tied to a particular application or a form of knowl- edge representation. We present an information- theoretic definition of similarity that is applica- ble as long as there is a probabilistic model. We demonstrate how our definition can be used to measure the similarity in a

Dekang Lin

1998-01-01

409

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

410

Laboratory Simulations  

NASA Astrophysics Data System (ADS)

Geophysical properties of near-Earth objects (NEOs) can best be studied using radio tomography and seismology. Reflection and transmission radio tomography is best suited for measuring the complex electric permittivity of poorly conducting materials to reveal the internal structure of NEOs. Such NEOs are primarily comet nuclei and carbonaceous asteroids. Seismic experiments are most suitable for studying elastic properties of consolidated materials to reveal material strengths of stony and iron-nickel asteroids. Thus, the two methods are complementary for investigating comets and asteroids of all types. Analysis of reflection and transmission radio tomography of heterogeneous irregular shaped bodies is very difficult. Scattering by internal and outer boundaries, differences in the refractive indices of heterogeneous materials, and attenuation by electric conductivity complicate the analyses. For this reason laboratory simulations with scaled objects and scaled wavelengths is extremely useful to check the reliability of inversion techniques of radio signals to arrive at the interior structure of an NEO. Another approach to obtaining quantitative information on the composition and structure of an NEO is through induced seismology. There are two approaches to producing seismic waves: small explosive charges and impactors. Experimental work has been performed in the laboratory to examine the impulse delivered by explosives. Wave travel times can be used to back out basic material properties and first order structure of an NEO. For example, if distinct arrival pulses for P and S waves are recorded and the explosive initiation/impact time and location are known, then it is possible to determine the elastic properties of bulk and shear modulus. Reflections in the seismograms allow a determination of material boundaries in an NEO. Original arrival time is important since Q numbers for stony NEO material are presumed to be high, as they were on the Moon, and thus it is expected that there will be extensive ringing and noise. Other types of NEO materials will have differing seismic characteristics.

Huebner, W. F.; Walker, J.; Gustafson, B.

411

Mice and men: Making the most of our similarities  

SciTech Connect

Because a big chunk of the genetic information that goes into building a mouse is also needed to put together a human, mice are often employed in the laboratory as genetic stunt doubles for man. In fact, the similarities between sections of human and mouse DNA enable researchers working with mouse genes to make surprisingly accurate predictions about the location and function of their human counterparts. For over 40 years, ORNL researchers have been studying the nuances of the genetic relationship between mice and humans, sometimes with considerable fanfare, other times in relative obscurity, but always with the goals of increasing the understanding of the subtle language of genetics and improving human lives. Some of the laboratory`s latest research in this area is described in this article.

Pearce, J.

1994-12-31

412

Population-typical behaviours are retained when eusocial and non-eusocial forms of Evylaeus albipes (F.) (Hymenoptera, Halictidae) are reared simultaneously in the laboratory  

Microsoft Academic Search

Summary. We compare the behaviour of daughters of Evylaeus albipes females from eusocial populations from the West of France with those from a non-eusocial population from the East of the country. When non-eusocial population females are placed in the laboratory under day lengths and temperature conditions similar to those experienced by eusocial foundresses under natural conditions, all five produced a

C. Plateaux-Qunu; L. Plateaux; L. Packer

2000-01-01

413

Multicellular microorganisms: laboratory versus nature  

PubMed Central

Our present in-depth knowledge of the physiology and regulatory mechanisms of microorganisms has arisen from our ability to remove them from their natural, complex ecosystems into pure liquid cultures. These cultures are grown under optimized laboratory conditions and allow us to study microorganisms as individuals. However, microorganisms naturally grow in conditions that are far from optimal, which causes them to become organized into multicellular communities that are better protected against the harmful environment. Moreover, this multicellular existence allows individual cells to differentiate and acquire specific properties, such as forming resistant spores, which benefit the whole population. The relocation of natural microorganisms to the laboratory can result in their adaptation to these favourable conditions, which is accompanied by complex changes that include the repression of some protective mechanisms that are essential in nature. Laboratory microorganisms that have been cultured for long periods under optimized conditions might therefore differ markedly from those that exist in natural ecosystems.

Palkova, Zdena

2004-01-01

414

Do Droughts Have Similar Consequences for Benthic Macroinvertebrate Communities in Similar Streams?  

NASA Astrophysics Data System (ADS)

Hydrologic variability due to drying is common in streams, but does a single drought disturbance have similar effects across streams? In 2002, a severe drought occurred during an experiment designed to test the influence of habitat heterogeneity on macroinvertebrate community stability in two New Hampshire streams. I used this "demonic intrusion" to compare the effects of a single drought disturbance on benthic community composition in two similar streams. Prior to the drought, Alder and Loomis Valley Brooks, were very similar in size, discharge, cover, substratum, and community composition. However, following the drought, both univariate and multivariate measures of community composition demonstrated dramatic differences between the two streams with Loomis Valley shifted towards a community dominated by collector/gathering taxa, and Alder Brook dominated by predators, shredding detritivores, grazers, and filter feeders. In both streams, habitat heterogeneity played little or no role in mediating drought effects. Many of the post-drought differences between streams may have resulted from differential hydrologic impacts of the drought: Loomis Valley was without visible surface flow for several weeks, while Alder had reduced but visible surface flow. These results demonstrate that drought effects on benthic macroinvertebrate communities must be considered in a context which incorporates local hydrologic conditions.

Brown, B. L.

2005-05-01

415

Laboratory Rodent Welfare: Thinking Outside the Cage  

Microsoft Academic Search

This commentary presents the case against housing rats and mice in laboratory cages; the commentary bases its case on their sentience, natural history, and the varied detriments of laboratory conditions. The commentary gives 5 arguments to support this position: (a) rats and mice have a high degree of sentience and can suffer, (b) laboratory environments cause suffering, (c) rats and

Jonathan Balcombe

2010-01-01

416

Efficient parallel set-similarity joins using MapReduce  

Microsoft Academic Search

In this paper we study how to efficiently perform set-simi- larity joins in parallel using the popular MapReduce frame- work. We propose a 3-stage approach for end-to-end set- similarity joins. We take as input a set of records and output a set of joined records based on a set-similarity condition. We efficiently partition the data across nodes in order to

Rares Vernica; Michael J. Carey; Chen Li

2010-01-01

417

Acoustic Similarity Law for Centrifugal Fans.  

National Technical Information Service (NTIS)

Acoustic similarity laws for fans were exerimentally verified. Three, dimensionally similar centrifugal fans of 140, 280 and 560 mm impeller diameter were used. The fans were connected to anechoically terminated discharge ducts. It is shown that the influ...

W. Neise B. Barsikow

1980-01-01

418

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.

419

Finding Similar Users in Social Networks  

Microsoft Academic Search

We consider a system where users wish to find similar users. To model similarity, we assume the existence of a set of queries,\\u000a and two users are deemed similar if their answers to these queries are (mostly) identical. Technically, each user has a vector\\u000a of preferences (answers to queries), and two users are similar if their preference vectors differ in

Aviv Nisgav; Boaz Patt-Shamir

420

Quantifying the Similarities within Fold Space  

Microsoft Academic Search

We have used GRATH, a graph-based structure comparison algorithm, to map the similarities between the different folds observed in the CATH domain structure database. Statistical analysis of the distributions of the fold similarities has allowed us to assess the significance for any similarity. Therefore we have examined whether it is best to represent folds as discrete entities or whether, in

Andrew Harrison; Frances Pearl; Richard Mott; Janet Thornton; Christine Orengo

2002-01-01

421

DOMAIN-SPECIFIC SIMILARITY AND RETRIEVAL  

Microsoft Academic Search

In this paper we introduce an approach to the modeling of conceptual similarity based on domain knowl- edge and an approach to aggregation to derive object similar- ity from concept similarity. Domain knowledge is represented in a special, so-called, domain-specific ontology, which basi- cally is a restriction of a general ontology by a collection of domain concepts or a given

Troels Andreasen; Rasmus Knappe; Henrik Bulskov

422

A Similarity Principle for Multipacting Discharges  

Microsoft Academic Search

A similarity principle is introduced for multipacting discharges in geometrically similar electrode configurations. For phase-similar breakdowns, it is shown that the rf and dc voltages are proportional to (fl)2, the electron velocity is proportional to fl, and the rf and dc magnetic fields are proportional to f, where f is the frequency of the rf voltage and l is the

Richard Woo; Akira Ishimaru

1967-01-01

423

Fast Similarity Search for Learned Metrics  

Microsoft Academic Search

We propose a method to efficiently index into a large database of examples a ccording to a learned met- ric. Given a collection of examples, we learn a Mahalanobis distance using an information-theoretic metric learning technique that adapts prior knowledge about pairwise distances to incorporate similarity and dis- similarity constraints. To enable sub-linear time similarity search under the lea rned

Brian Kulis; Prateek Jain; Kristen Grauman

2009-01-01

424

Spontaneous similarity discrimination in the evolution of cooperation.  

PubMed

The similarity discrimination effect occurs when a single gene or gene cluster causes its carriers to display both a variable phenotypic trait and a behavioural predisposition to cooperate preferentially with recognisably similar carriers. We distinguish this from the greenbeard effect, in which cooperation evolves through fixed phenotypic tags and genetically linked cooperative behaviour with others displaying the same tag. Our agent-based simulations show that the evolution of cooperation through similarity discrimination, in contrast to the greenbeard effect, does not depend on population viscosity or other restrictive conditions. Similarity discrimination evolves spontaneously in well mixed populations, not only in the Prisoner's Dilemma game but also across a range of different binary-choice strategic interactions, provided that agents can distinguish reliably between similar and dissimilar co-players. PMID:21640125

Colman, Andrew M; Browning, Lindsay; Pulford, Briony D

2011-05-26

425

The Influence of Phonological Similarity Neighborhoods on Speech Production  

PubMed Central

The influence of phonological similarity neighborhoods on the speed and accuracy of speech production was investigated with speech-error elicitation and picture-naming tasks. The results from 2 speech-error elicitation techniquesthe spoonerisms of laboratory induced predisposition technique (B. J. Baars. 1992; B. J. Baars & M. T. Motley, 1974; M. T. Motley & B. J. Baars, 1976) and tongue twistersshowed that more errors were elicited for words with few similar sounding words (i.e., a sparse neighborhood) than for words with many similar sounding words (i.e., a dense neighborhood). The results from 3 picture-naming tasks showed that words with sparse neighborhoods were also named more slowly than words with dense neighborhoods. These findings demonstrate that multiple word forms are activated simultaneously and influence the speed and accuracy of speech production. The implications of these findings for current models of speech production are discussed.

Vitevitch, Michael S.

2008-01-01

426

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 their spectral variability between samples representing the different types of HEDs and to describe the spectral heterogeneity for each samples. A preliminary comparison with mineralogical and petrographic characteristics has been done describing hand samples and their thin sections. These data will be incorporated in a spectral library that could be an useful tool for the interpretation of data acquired by the Dawn mission in orbit on Vesta.

Farina, M.; Coradini, A.; Carli, C.; Ammannito, E.; Consolmagno, G.; De sanctis, M.; Di Iorio, T.; Turrini, D.

2011-12-01

427

Electrolyte conditioning-enhanced electrokinetic remediation of arsenic-contaminated mine tailing.  

PubMed

Feasibility of electrolyte conditioning with strong acidic or alkaline solution on electrokinetic remediation of arsenic-contaminated mine tailing was investigated in the laboratory. The mine tailing contained calcium oxide of more than 50%. At alkaline condition, arsenic was precipitated with calcium, and formed calcium arsenate which is very stable solid. Catholyte conditioning with strong acidic solution and anolyte conditioning with strong alkaline solution showed similar efficiency to remove arsenic. At 4mAcm(-2) of current density, the removal efficiency of arsenic was 62% after 28 days operation with catholyte conditioning with 0.1M nitric acid. PMID:18479814

Baek, Kitae; Kim, Do-Hyung; Park, Sung-Woo; Ryu, Byung-Gon; Bajargal, Tserennyam; Yang, Jung-Seok

2008-04-07

428

Similarity-based Classification: Concepts and Algorithms  

Microsoft Academic Search

This paper reviews and extends the field of similarity-based classification, presenting new analy- ses, algorithms, data sets, and a comprehensive set of experimental results for a rich collection of classification problems. Specifically, the generalizability of using similarities as features is ana- lyzed, design goals and methods for weighting nearest-neighbors for similarity-based learning are proposed, and different methods for consistently converting

Yihua Chen; Eric K. Garcia; Maya R. Gupta; Ali Rahimi; Luca Cazzanti

2009-01-01

429

On Top-k Structural Similarity Search  

Microsoft Academic Search

Search for objects similar to a given query object in a network has numerous applications including web search and collaborative filtering. We use the notion of structural similarity to capture the commonality of two objects in a network, e.g., if two nodes are referenced by the same node, they may be similar. Meeting-based methods including SimRank and P-Rank capture structural

Pei Lee; Laks V. S. Lakshmanan; Jeffrey Xu Yu

2012-01-01

430

Distributed similarity estimation using derived dimensions  

Microsoft Academic Search

Computing the similarity between data objects is a fundamental operation for many distributed applications such as those on\\u000a the World Wide Web, in Peer-to-Peer networks, or even in Sensor Networks. In our work, we provide a framework based on Random\\u000a Hyperplane Projection (RHP) that permits continuous computation of similarity estimates (using the cosine similarity or the\\u000a correlation coefficient as the

Konstantinos Georgoulas; Yannis Kotidis

431

PHYSIOLAB: A cardiovascular laboratory  

NASA Astrophysics Data System (ADS)

PHYSIOLAB is a cardio-vascular laboratory designed by CNES in cooperation with IMBP, with double scientific and medical goals: a better understanding of the basic mechanisms involved in blood pressure and heart rate regulation, in order to predict and control the phenomenon of cardio-vascular deconditionning. a real-time monitoring of cosmonauts during functionnal tests. Launched to the MIR station in 1996, this laboratory was set up and used for the first time by Claudie Andr-Deshays during the French mission ? Cassiopeia ?. The scientific program is performed pre, post and in-flight to study phenomena related to the transition to microgravity as well as the return to the earth conditions. Particular emphasis was placed on the development of the real-time telemetry to monitor LBNP test. This function was successfull during the Cassiopeia mission, providing the medical team at TSOUP (MIR Control Center in Moscow) with efficient means to control the physiological state of the cosmonaut. Based on the results of this first mission, IMBP and CNES will go on using Physiolab with Russian crews. CNES will take advantage of the upcoming French missions on MIR to improve the system, and intends to develop a new laboratory for the International Space Station.

Cauquil, D.; Laffaye, C.; Camus, A. L.; Weerts, G.; Gratchev, V.; Alferova, I.; Kotovskaya, A.

432

Self-similar modes of coherent diffusion.  

PubMed

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, based on the elegant Gaussian modes of optical diffraction. In a light-storage experiment, the complex solutions are imprinted on a gas of diffusing atoms, and the self-similar evolution of both their amplitude and phase pattern is demonstrated. An algebraic decay depending on the mode order is measured. Notably, as opposed to the regular diffusion spreading, a subset of the solutions exhibits a self-similar contraction. PMID:21231104

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

2010-10-27

433

Study of Transmission and Distribution Laboratory Facilities.  

National Technical Information Service (NTIS)

A comprehensive survey of existing laboratories and field test facilities, capable of conducting transmission and distribution research, in the United States and Canada and similar well-known facilities located in Europe was made. Major areas covered by t...

1975-01-01

434

Marking Student Programs Using Graph Similarity  

ERIC Educational Resources Information Center

|We present a novel approach to the automated marking of student programming assignments. Our technique quantifies the structural similarity between unmarked student submissions and marked solutions, and is the basis by which we assign marks. This is accomplished through an efficient novel graph similarity measure ("AssignSim"). Our experiments

Naude, Kevin A.; Greyling, Jean H.; Vogts, Dieter

2010-01-01

435

From Contour Similarity to Motivic Topologies  

Microsoft Academic Search

This paper is devoted to a qualitative and quantitative study of topological spaces built on premotif collections of musical scores. These motivic topologies are related to similarity concepts in the American music set theory. Through shapes, imitations and gestalts, and similarity relations between any two shapes, we obtain a motivic hierarchy of a score. This model of motivic analysis is

Chantal Buteau; Guerino Mazzola

2000-01-01

436

Gender Similarities and Mathematics and Science Education  

Microsoft Academic Search

This article extends the discussion of gender similarities to address additional implications of the findings and to include the issue of variability in scores. We explore the possibility that males display greater variability in scores so that, even if average scores for males and females are quite similar, a preponderance of males would be found in the upper (and lower)

Janet Shibley Hyde; Marcia C. Linn

437

Documents Similarity Measurement Using Field Association Terms.  

ERIC Educational Resources Information Center

|Discussion of text analysis and information retrieval and measurement of document similarity focuses on a new text manipulation system called FA (field association)-Sim that is useful for retrieving information in large heterogeneous texts and for recognizing content similarity in text excerpts. Discusses recall and precision, automatic indexing

Atlam, El-Sayed; Fuketa, M.; Morita, K.; Aoe, Jun-ichi

2003-01-01

438

Extended self-similarity in turbulent flows  

NASA Astrophysics Data System (ADS)

We report on the existence of a hitherto undetected form of self-similarity, which we call extended self-similarity (ESS). ESS holds at high as well as at low Reynolds number, and it is characterized by the same scaling exponents of the velocity differences of fully developed turbulence.

Benzi, R.; Ciliberto, S.; Tripiccione, R.; Baudet, C.; Massaioli, F.; Succi, S.

1993-07-01